The clinical performance of ultra-low-dose shoulder CT scans: The assessment on image and physical 3D printing models

Ming Lei; Meng Zhang; Niyuan Luo; Jingzhi Ye; Fenghuan Lin; Yanxia Chen; Jun Chen; Mengqiang Xiao

doi:10.1371/journal.pone.0275297

. 2022 Sep 26;17(9):e0275297. doi: 10.1371/journal.pone.0275297

The clinical performance of ultra-low-dose shoulder CT scans: The assessment on image and physical 3D printing models

Ming Lei ¹, Meng Zhang ¹, Niyuan Luo ¹, Jingzhi Ye ¹, Fenghuan Lin ¹, Yanxia Chen ¹, Jun Chen ¹, Mengqiang Xiao ^1,^*

Editor: Jonas Bianchi²

PMCID: PMC9512178 PMID: 36155982

Abstract

Objectives

Evaluation of the clinical performance of ultra-low-dose computed tomography (CT) images of the shoulder joint on image-based diagnosis and three-dimensional (3D) printing surgical planning.

Materials and methods

A total of 93 patients with displaced shoulder fractures were randomly divided into standard-dose, low-dose, and ultra-low-dose groups. Three-dimensional printing models of all patients’ shoulder joints were fabricated. The subjective image quality and 3D-printing model were evaluated by two senior orthopedic surgeons who were blinded to any scanning setting. A 3-point scale system was used to quantitatively assess the image quality and 3D printing model, where more than 2 points meant adequate level for clinical application.

Results

Compared with the standard dose protocol, ultra-low-dose technique reduced the radiation dose by 99.29% without loss of key image quality of fracture pattern. Regarding the subjective image quality, the assessment scores for groups of standard, low, and ultra-low doses were 3.00, 2.76, 2.00 points on scapula and humerus, and 3.00, 2.73, 2.44 points on clavicle. Scores of the three groups for the assessment of 3D printing models were 3.00, 2.80, 1.34 on scapula and humerus, and 3.00, 2.90, 2.06 on clavicle. In the ultra-low-dose group, 24 out of 33 (72.7%) 3D printing models of scapula and humerus received lower than 2 points of the evaluation score, while nearly 94% of the clavicle models reached the adequate level.

Conclusion

An ultra-low-dose protocol is adequate for the diagnosis of either displaced or non-displaced fractures of the shoulder joint even though minor flaws of images are present. Three-dimensional printing models of shoulder joints created from ultra-low-dose CT scans can be used for surgical planning at specific bone like the clavicle but perform insufficiently in the overall surgical planning for shoulder injuries due to the significant geometric flaws.

Introduction

Shoulder injury is primarily examined by conventional radiography and is likely to be further examined by computed tomography (CT) to detect the fracture profile [1]. Computed tomography is superior to radiography for characterizing fracture patterns [2], particularly for regions with anatomic complexity such as shoulder joints. The dose of radiation for traditional CT on a shoulder joint is extremely high with 5.28 mSv in comparison to conventional radiography, which is less than 0.011 mSv [3, 4]. The risk of increased ionizing radiation exposure is the primary safety concern for having a CT scan [5]. According to the data collected in the United States from 1991 to 1996, malignant tumors caused by CT radiation account for 0.4% of all malignant tumors [6–8]. The high dose of radiation of conventional CT scans for patients with bone injuries restricts its application for regular diagnosis. Employing low-dose CT on diagnosis and surgical procedure has been of growing interest in clinical research with the technical advantage of CT scans being to detect detailed anatomical structure. Many researchers targeted the technical solution to reduce the negative effect of low image accuracy acquired from low-dose CT scans [9–12]. Convolutional neural networks and iterative reconstruction algorithms were reported to use for improving image quality [13]. Some published studies confirmed the significantly reduced rates of effective radiation dose, from 49% to 97%, without losing the critical image quality acquired from low-dose CT scans and iterative reconstruction technique [9–12].

A digital three-dimensional (3D) model created from CT scans is not only employed on diagnosis and surgical assistance of bone injury but is also used to create physical models of bone for surgical planning. Bone and joint fractures and anatomical structures of the shoulder can be represented in a 3D-printed model which can be used to develop favorable surgical plans and optimize a surgical protocol. Surgeons have previously employed 3D-printed models to extract the fracture line of a shoulder joint and make a surgical plan for internal fixation implants [14, 15]. Clinicians have utilized 3D-printed models to simulate the surgical procedure of a shoulder joint to guide the implant location and size [16]. Furthermore, a 3D-printed model is an excellent tool for communication between clinicians and patients who can understand the treatment procedure and outcomes even though they lack medical knowledge [17].

Radiation dose of CT scans is positively correlated with CT image quality. There are few studies on the comparative assessment of diagnosis performance among different radiation doses of CT scans. Xiao et al. reported that 3D printed models created from low-dose CT images effectively evaluate the clinical performance of diagnosis and surgical planning [9]. However, assessment of clinical performance on the diagnosis and surgical planning by using 3D printing models created from low-dose shoulder CT images has not been studied. Here, we hypothesize that low dose CT scans meet the clinical needs for fracture diagnosis and 3D printing models. The aim of this study is to evaluate the clinical performance of ultra-low-dose CT images of shoulder joints on the image-based diagnosis and physical model-based (3D printing) surgical planning.

Materials and methods

Patient selection

This prospective study was approved by the institutional ethics committee of the (BF2019-030-01). All patients visiting our hospital for CT imaging for the diagnosis of shoulder trauma were entered into this study. Inclusion criteria were set as follows: age over 18 years, signed written consent for participation, and admission from the emergency department with symptoms of shoulder fracture, non-osteoporosis (bone density: lumbar spine and/or hip joint T-score > -2.5). Exclusion criteria were as follows: less than 18 years of age, pregnancy, patients who refused to participate in the study, and patients with osteoporosis (bone density: lumbar spine and/or hip joint T-score < -2.5) or pathological fractures. Poor image quality of bone would be present on an osteoporosis patient who has significant low bone mass. This may induce poor grey contrast level between bone and surrounding soft tissues.

Patients with shoulder fractures were randomly divided into three groups: a standard-dose group (150 mAs, 120 kV, limb joints No-smart-milliampere) [18], a low-dose group with (105 mAs, 100 kV), and an ultra-low-dose group (52 mAs, 80 kV). The above scanning configurations were set based on the CT Whole Body Phantom "PBU-60 (Kyoto Kagaku Co., Ltd) and pre-experimental CT scans. The CT parameters for each group are listed in Table 1. Written informed consent was obtained from eligible participants.

Table 1. CT parameters and patient information of each group.

Dose group	Standard	Low-dose	Ultra-low-dose	P
Tube voltage (kV)	120	100	80
Tube current (mA)	150	140	70
D-FOV (mm)	500	500	500
Rotation time (s)	1	0.75	0.75
Thickness (mm)	0.5	0.5	0.5
Interval (mm)	0.5	0.5	0.5
Scan length (cm)	160	160	160
AIRD3D	Standard	Standard	Standard
No.	30	30	33
Age(year)	57.17 ± 13.84	58.33 ± 19.22	59.09 ± 15.96	0.90
Gender (Male/Female)	15/15	10/20	13/20	0.26
Normal bone mass/osteopenia (case)	14/16	11/19	13/20	0.75
Displaced/Non-displaced fracture (case)	30/0	30/0	33/0	0.99
Comminuted/simple fracture(case)	29/1	29/1	27/6	0.99
Clavicle fracture (case)	12	8	9	0.46
Humerus fracture (case)	15	20	20	0.26
Scapula fracture (case)	1	1	2	0.83
Two bones fracture (case)	2	1	2	0.91

Open in a new tab

D-FOV: Display Field of View

AIRD3D: Adaptive Iterative Dose Reduction

Sample size determination

The sample size was calculated using the G*Power software for a priori analysis, with a sensitivity of 95% (α = 0.05) and a study power of 90% (β = 0.10). Since the patients were classified into three groups based on the dose, the effect size was determined by a one-way analysis of variance (ANOVA) using the effect size measure Cohen’s f. The resulting sample size n is 12. If 10% missing values were defined, the sample size (n = 15 per group) is sufficient for the study.

Image acquisition

All selected subjects were scanned using a Toshiba 320-slice dynamic CT scanner (Canon Aquilion One, Japan) with a 0.5 mm slice thickness. The scanning parameters (tube voltage and current) for each group are shown in Table 1. Patients’ images were reconstructed by using adaptive iterative dose reduction (3D standard; Canon Medical Systems). Two dose metrics, volumetric CT dose index (CTDIvol; mGy) and dose length product (DLP; mGy*cm) were reported. The effective dose (ED; mSv) for each examination was calculated by multiplication of the DLP and a body region-specific conversion factor k (mSv/DLP) for the hip [19].

Preparation of three-dimensional models

Patients’ 3D models of shoulder joints were reconstructed from the original CT data stored in DICOM format by using Mimics Research 19.0 (Materialise, Belgium). The threshold value was set to “soft tissue (CT) 26-Max” for bone reconstruction. These 3D models (saved as MCS format) were further transferred in Gcode format by using specific software provided by the manufacturer of the 3D printer (Tianwei ColiDo 3.0, China). It took approximately 15.5 hours to print each model. The printing material was polylactic acid. The resolution of the printed models was 0.011 mm × 0.011 mm × 0.0025 mm.

Types of fractures in each group

In this study, shoulder fractures were divided into simple fractures and comminuted fractures (defined as fractures in which the bone was broken with 3 or more pieces) in terms of the strategy of treatment. Non-surgical treatment is mostly used for simple fracture, which is also treated by surgery in some relatively severe cases. Comminuted displaced fractures have to be treated by surgery [20]. According to the severity of fracture displacement, fractures were also split into displaced and non-displaced fractures. Non-displaced fractures are defined as having no angulation or shortening, a fracture line less than 2 mm wide and/or less than 1 mm displacement of the bone cortex. Displaced fractures are defined as having a fracture line more than 2 mm wide and/or more than 1 mm displacement of the bone cortex. Avulsion fractures caused by a sudden and violent contraction of a muscle or ligament, were grouped into non-displaced fractures or displaced fractures when the fracture had a long-diameter ≤ 5 mm or > 5 mm wide bone piece, respectively [21].

Assessment of image quality

Two senior radiologists, who were part of a national board of radiologists and were clinicians with over 10 years of clinical experience for clinical diagnosis of musculoskeletal diseases performed quality assessment of CT images. They were blinded to the results of the study.

The objective CT image quality metrics were performed by a senior radiologist. An oval shape of region of interest (ROI) was placed on the thickest region of the cross section of the cortical shell of the shoulder bones. The oval ROI was equal to 15 mm². A circular ROI with 100 mm² was placed within muscle. Computed tomography values of shoulder muscle (CTm), and shoulder cortical bone (CTc) were determined. The contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were calculated in terms of following equations [9]:

Signal-to-noise ratio = CTm mean / standard deviation (SD) mean

Contrast-to-noise ratio = (CTc mean–CTm mean) / SD mean.

The assessment of the subjective image quality of the fracture profile, which we hereafter termed as the “fracture line score”, was performed by two radiologists with rich experience in diagnosing musculoskeletal diseases. They were blinded to the scanning parameters and rated the image quality based on a 3-point score system as previously reported [9]: 3 = good (good visualization of fracture line, excellent definition of fracture profile, see Figs 1 and 2); 2 = adequate (adequate visualization of fracture line, slightly impacted by the image noise, good definition of fracture profile, see Fig 3); 1 = poor (inadequate visualization of fracture line, poor definition of fracture profile, see Fig 4).

Fig 1 — 1A: oblique coronal reconstruction images show the fracture line (arrow), and scored 3 points. 1B: Three-dimension reconstruction images show the fracture lines (arrow), 3 points. 1C and 1D: Three-dimension printed model, scored 3 points.

Fig 2 — 2A: oblique coronal reconstruction images show the fracture line (arrow), scored 3 points. 2B: Three-dimension reconstruction images show the fracture lines (arrow), scored 3 points. 2C and 2D: Three-dimension printed models of the clavicle and the scapula and humerus, respectively, scored 3 points.

Fig 3 — 3A: axial images show the fracture line (arrow), scored 2 points. 3B: Three-dimension reconstruction images show the fracture line (arrow), scored 2 points. 3C: Three-dimension printed model, scored 2 points.

Fig 4 — 4A: axial image shows the fracture line (arrow), scored 2 points. 4B and 4D: Three-dimension reconstruction images of the clavicle show the fracture line (arrow). 4B: Three-dimension reconstruction images, scored 2 points. 4C: Three-dimension printed model of the scapula and humerus, scored 1 point.

Assessment of three-dimensional printing models quality

The assessment of 3D printing models was performed by two senior orthopedic surgeons who were blinded to the scanning parameters. The evaluation criteria were based on accuracy and clarity of anatomic structure for surgical planning purposes. A 3-point rating system developed by published studies was employed for the assessment: 3 = good (smooth surface of a model with high similarity of anatomic structure, quite applicable for surgical planning); 2 = adequate (slightly coarse surface of a model with minor geometric flaws, applicable to the basic surgical planning not affected by the minor flaws); 1 = poor (coarse surface of a model with distinct geometric flaws, not applicable to surgical planning) [9, 22, 23].

Gold standard of diagnosis performance

The gold standard of diagnosis performance is surgical findings or computed tomography/Diagnostic Radiology re-examination. For fractures treated with surgery, the diagnosis was made by observing the fracture directly during surgery. For fractures by expectant treatment, the diagnosis was made based on the CT/DR review within 1–3 months: callus at the fracture end; dysplasia or old fracture without callus.

Statistical analysis

The statistical package SPSS version 26.0 software (IBM Corp, Armonk, NY, USA) was used for all statistical analyses. Continuous data were expressed as means±SD. Comparisons among the standard-dose, low-dose, and ultra-low-dose groups were conducted by using independent sample ANOVA tests. The Tamhane’s T2 test was employed to assess the difference in quality scores of CT images and 3D-printed models. The intraclass correlation coefficient (ICC) test was used to analyze the interobserver agreement in the qualitative evaluation. An ICC value > 0.8 was considered as agreement.

Results

This study was comprised of 93 patients with a mean age of 58.33 years (range, 18–89 years). A total of 55 (59.1%) of the patients were male. There were no statistical differences in age or gender (Table 1). Patients with normal bone density or osteopenia were randomly assigned in the standard, low-dose, and ultra-low-dose groups and generated the following distribution: 14 (normal bone density)/16 (osteopenia), 11/19, and 13/20 respectively. All patients suffered a displaced fracture (Table 1). The standard and low-dose group had 1 simple and 29 comminuted fractures while the ultra-low-dose group had 6 simple and 27 comminuted fractures (Table 1). Fractures were present in three important bones of the shoulder joint, clavicle, humerus, and scapula, in all groups. The distribution of clavicle fractures of three groups (from standard to ultra-low-dose groups) were 12, 8, 9. Fractures of the humerus and/or scapula in three groups were 18, 22, 24, as shown in Table 1.

The radiation dose of the ultra-low dose protocol was reduced by 99.29% compared with standard counterpart, 0.228 vs 3.216 on effective dose values. The mean volumetric CT dose index of the three groups (from standard to ultra-low-dose) was 15.26, 6.66, and 1.65 respectively, and the mean DLP (mGy*cm) values were 229.73, 101.59, and 25.15 respectively, as shown in Table 2.

Table 2. Objective image evaluation of the different groups.

Dose group	Standard	Low-dose	Ultra-low-dose	P
CTDIvol (mGy)	15.263 ± 0.605 ^a	6.660 ± 0.257 ^b	1.654 ± 0.066 ^c	0.001
DLP (mGy*cm)	229.733 ± 29.087 ^a	101.586 ± 12.487 ^b	25.154 ± 2.884 ^c	0.001
ED (mSv)	3.216 ± 0.328 ^a	1.086 ± 0.135 ^b	0.228 ± 0.026 ^c	0.001
CTc	1,737.30 ±101.01 ^a	1,897.84 ± 130.42 ^b	2,124.72 ± 264.15 ^c	0.001
CTc-CTm	1,675.79 ± 97.31 ^a	1,840.07 ± 128.59 ^b	2,058.25 ± 272.21 ^c	0.001
SD	15.11 ± 37 ^a	22.47 ± 6.17 ^b	33.53 ± 8.28 ^c	0.001
SNR	57.99 ± 12.44 ^a	39.00 ± 12.27 ^b	26.14 ± 7.95 ^c	0.001
CNR	114.81 ± 22.82 ^a	87.22 ± 22.90 ^b	65.16 ± 18.18 ^c	0.001

Open in a new tab

Data are presented as mean ± standard deviation.

Analysis of variance (F-test) between three groups. P < 0.05 means statistically significant. ^aP = 0.001 vs Low-dose; ^bP = 0.001 vs Ultra-low-dose; ^cP = 0.001 vs Standard.

The fracture line scores, which represented the subjective image quality, of the three bones of the shoulder (the scapula, humerus, and clavicle) were positively dependent on the radiation dose of images and dropped from 3 to 2 as the radiation dose decreased across the three groups (Table 3). The fracture line score of clavicles with ultra-low-dose was 2.4, while the standard dose was given a higher score of 3.

Table 3. Subjective evaluation of the different groups.

Dose group	Bone	Standard	Low-dose	Ultra-low	P
Facture line score	Clavicle	2.999 ± 0.001^a	2.7270 ± 0.467^b	2.444 ± 0.527^c	0.001
Facture line score	Scapula and Humerus	2.999 ± 0.001 ^a	2.761 ± 0.436 ^b	2.000 ± 0.001 ^c	0.001
3D model score	Clavicle	2.999 ± 0.001^a	2.900 ± 0.305^a	2.062 ± 0.435^b	0.001
3D model score	Scapula and Humerus	2.999± 0.001 ^a	2.800 ± 0.406 ^b	1.343 ± 0.482 ^c	0.001

Open in a new tab

Data are presented as mean ± standard deviation.

Clavicle, Scapula and Humerus facture line score: Analysis of variance (F-test); F = 23.85–1049.35, ^aP = 0.001 vs Low-dose; ^bP = 0.001 vs Ultra-low-dose; ^cP = 0.001 vs Standard. Clavicle 3D model score value: Analysis of variance (F-test); ^aP = 0.078 vs Low-dose, F = 3.22; ^bP = 0.001 vs Ultra-low-dose, F = 75.99; ^cP = 0.001 vs Standard, F = 38.98. Scapula and Humerus 3D model score value: ^aP = 0.009 vs Low-dose, F = 7.25; ^bP = 0.001 vs Ultra-low-dose, F = 163.92; ^cP = 0.001 vs Standard, F = 353.04.

Three-dimension printed models in the standard dose group scored 3 points (see Fig 1). The score of a 3D printing model declined as the radiation dose reduced. The clavicle models of the ultra-low-dose group had a mean of 2.06 on the evaluation score while the 3D printing models of the scapula and humerus created from ultra-low-dose CT scans received a lower score (1.34) (see Fig 4) (Table 3).

The ICC values for the evaluation scores on 3D printed models and fracture lines of the clavicle were 0.889 and 0.872, respectively. The same ICC value (0.872) was obtained from the evaluation scores on 3D printed models and fracture lines of the scapula and humerus.

Discussion

This is the first study to perform an assessment on the clinical performance of ultra-low-dose radiation on the image and physical model of shoulder joints. Assessments covered ultra-low-dose to standard dose to investigate the comparative performance among different radiation doses. Three-dimension printing physical models of shoulder joints were firstly used to evaluate the radiation-dose-related clinical performance for shoulder injuries. A combination of image and real entity is a technical method to help provide an answer to patients’ and clinicians’ concerns regarding an optimal balance between radiation-related health risk, diagnostic accuracy, and surgical optimization for shoulder injuries.

Sound clinical performance was present in the 3D printing models of the clavicle created from ultra-low-dose CT scans. Favorable accuracy of anatomic structure allowed those models to score high on surgical planning, with more than 2 points on the evaluation score given by senior radiologists. Experimental results demonstrated that approximately 94% of these 3D printed models had sufficient accuracy in terms of anatomic detail to perform surgical planning. There are no published studies investigating the clinical performance of ultra-low-dose CT imaging on shoulder treatment strategy.

We have previously demonstrated that the quality of CT images at the wrist joint meet the needs of clinical fracture diagnosis and the image quality of the 3D model created from ultra-low-dose CT scans is good enough for the surgical planning [9]. However, in terms of the scapula part of the shoulder joint, the image quality of ultra-low dose CT meets the needs of clinical fracture diagnosis, but the image quality of the 3D model is too low for the surgical planning. Despite the favorable performance of an ultra-low-dose protocol on the clavicle model, the ultra-low-dose protocol did not extend its clinical benefit on the 3D-printed model of the scapula and humerus. These models were scored much lower (less than 1.5 out of 3) by professional experts, and nearly 73% of the 3D-printing models on these bones were inapplicable to clinical planning, suggesting a failure of clinical application of 3D-printing models of the scapula and humerus by using an ultra-low-dose protocol. To our knowledge, an extremely thin layer of cortical bone of the humeral head and scapula body may be the reason for poor gray level contrast development with respect to the surrounding soft tissues, particularly imaging under ultra-low radiation dose (Fig 4). There is no doubt that a high radiation dose of CT scans leads to the development of higher-definition images.

The conventional orthopaedic surgery system does not have high requirements for 3D printing accuracy, which is enough to reach 0.1 mm. In this subject, extrusion 3D printing (fused deposition modeling, FDM) is the cheapest of all 3D printing, and the 3D printing accuracy is 0.011 mm, which fully meets the demand. Higher precision 3D printing is too high cost and is not conducive to research, making it difficult for 3D printing technology to be popularized in hospitals. The relatively low-cost material PLA (Tianwei Co., Ltd., US $9.83 for 1KG PLA material) was used. Printing one 3D model costs about $2.16 and takes about 15.51±1.20 hours. In our study, 3D printing process self-study videos were provided by 3D printing manufacturers, and 3D modeling parameters were adjusted remotely by the manufacturers. Ordinary computers could run the software, which was easy to learn.

The ultra-low-dose protocol functioned well in the diagnosis of fracture pattern of an injured shoulder. The ultra-low-dose protocol scored more than 2 points in subjective image quality (Table 2), which suggests that a good balance between low health risk and acceptable diagnosis accuracy can be reached. Alagic et al. [24] found that ultra-low-dose CT was a sound alternative to conventional radiography in the diagnosis of peripheral skeleton injury (wrist, ankle, and knee) as it had distinct technical strength in providing a detailed fracture pattern inside the bone as well as a comparable radiation dose. It is not possible to suggest that ultra-low-dose radiation is superior to the conventional standard dose in terms of clinical application as the latter received a full score in the evaluation of subjective image quality.

A significant reduction in the radiation dose, by using an appropriate setting of scanning parameters, can significantly reduce the negative influence of dose-related image quality of the shoulder joint. The ultra-low-dose technique employed in this study reduced the tube voltage by 33% and halved the tube current when compared to the standard-dose protocol. Furthermore, the algorithm of adaptive iterative dose reduction used in this study effectively worked on noise reduction and improvement of image quality [9, 25, 26]. These technical means reduced the effective radiation by 99.29%. Interestingly, the image quality was not visually faded and was still well workable on the diagnosis. Further evaluation of the subjective image quality reached a favorable level, more than 2 out of 3 points of the assessment score. Notably, assessment of image quality of the shoulder joint, either on the definition of the type of fracture or the severity of fracture, matched the gold standard developed from surgical findings. There were precedents reported in published studies with focused on examination of extremities (shoulder, pelvis, ankle, and wrist) where the radiation dose was reduced to 50% [3].

There are some limitations in this research. Firstly, an in-depth assessment of the diagnosis performance of an ultra-low-dose protocol on acute shoulder injuries, where high-definition images were required, was not conducted in this study. Furthermore, the 3D printing technique would not be recommended for emergency diagnosis or treatment of shoulder injury due to the time consuming printing procedure and expensive fabrication cost. It should be noted that the image quality is associated with a variety of CT scanner hardware and software, such as tube or detector material, iterative reconstruction algorithm, etc. Radiation dose is not the only key component to evaluate the image quality.

Conclusions

An ultra-low-dose protocol is adequate for the diagnosis of either displaced or non-displaced shoulder joint fractures even though minor flaws in the images are present. Three-dimension printing models of the shoulder joint created from ultra-low-dose CT scans can be used in the surgical planning of specific bones like the clavicle but perform insufficiently in the overall surgical planning for shoulder injuries due to the significant geometric flaws. Radiation dose should increase in order to obtain high-definition CT images for developing accurate 3D printing models.

Supporting information

S1 Checklist

(DOC)

Click here for additional data file.^{(196.5KB, doc)}

S1 File

(PDF)

Click here for additional data file.^{(128.3KB, pdf)}

Data Availability

The datasets generated and/or analyzed during the current study are not publicly available due to limitations of ethical approval involving the sensitive patient information and anonymity, but are available from the Corresponding Author, or from ethics committee representative Xiaoyan Li (llbgs@gzucm.edu.cn), on reasonable request.

Funding Statement

The author(s) received no specific funding for this work.

References

1.Amini B, Beckmann NM, Beaman FD, Wessell DE, Bernard SA, Cassidy RC, et al. ACR Appropriateness Criteria(®) Shoulder Pain-Traumatic. J Am Coll Radiol. 2018;15(5s):S171–s88. Epub 2018/05/05. doi: 10.1016/j.jacr.2018.03.013 . [DOI] [PubMed] [Google Scholar]
2.Ozaki R, Nakagawa S, Mizuno N, Mae T, Yoneda M. Hill-sachs lesions in shoulders with traumatic anterior instability: evaluation using computed tomography with 3-dimensional reconstruction. Am J Sports Med. 2014;42(11):2597–605. Epub 2014/09/19. doi: 10.1177/0363546514549543 . [DOI] [PubMed] [Google Scholar]
3.Yi JW, Park HJ, Lee SY, Rho MH, Hong HP, Choi YJ, et al. Radiation dose reduction in multidetector CT in fracture evaluation. Br J Radiol. 2017;90(1077):20170240. Epub 2017/07/15. doi: 10.1259/bjr.20170240 ; PubMed Central PMCID: PMC5858798. [DOI] [PMC free article] [PubMed] [Google Scholar]
4.Singh T, Muscroft N, Collier N, England A. A comparison of effective dose and risk for different collimation options used in AP shoulder radiography. Radiography (Lond). 2021. Epub 2021/12/11. doi: 10.1016/j.radi.2021.11.007 . [DOI] [PubMed] [Google Scholar]
5.Azman RR, Shah MNM, Ng KH. Radiation Safety in Emergency Medicine: Balancing the Benefits and Risks. Korean journal of radiology. 2019;20(3):399–404. Epub 2019/02/26. doi: 10.3348/kjr.2018.0416 ; PubMed Central PMCID: PMC6389812. [DOI] [PMC free article] [PubMed] [Google Scholar]
6.Ron E. Cancer risks from medical radiation. Health Phys. 2003;85(1):47–59. Epub 2003/07/11. doi: 10.1097/00004032-200307000-00011 . [DOI] [PubMed] [Google Scholar]
7.Oestreich AE. RSNA centennial article: ALARA 1912: "As low a dose as possible" a century ago. Radiographics. 2014;34(5):1457–60. Epub 2014/09/11. doi: 10.1148/rg.345130136 . [DOI] [PubMed] [Google Scholar]
8.Mathews JD, Forsythe AV, Brady Z, Butler MW, Goergen SK, Byrnes GB, et al. Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ. 2013;346:f2360. Epub 2013/05/23. doi: 10.1136/bmj.f2360 ; PubMed Central PMCID: PMC3660619 at www.icmje.org/coi_disclosure.pdf and declare: support from the Australian government (via the National Health and Medical Research Council, salary support from the Cancer Research Campaign UK and other agencies) for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work. [DOI] [PMC free article] [PubMed] [Google Scholar]
9.Xiao M, Zhang M, Lei M, Hu X, Wang Q, Chen Y, et al. Application of ultra-low-dose CT in 3D printing of distal radial fractures. Eur J Radiol. 2021;135:109488. Epub 2021/01/02. doi: 10.1016/j.ejrad.2020.109488 . [DOI] [PubMed] [Google Scholar]
10.Hamard A, Greffier J, Bastide S, Larbi A, Addala T, Sadate A, et al. Ultra-low-dose CT versus radiographs for minor spine and pelvis trauma: a Bayesian analysis of accuracy. Eur Radiol. 2021;31(4):2621–33. Epub 2020/10/10. doi: 10.1007/s00330-020-07304-8 . [DOI] [PubMed] [Google Scholar]
11.Yeom JA, Roh J, Jeong YJ, Lee JC, Kim HY, Suh YJ, et al. Ultra-Low-Dose Neck CT With Low-Dose Contrast Material for Preoperative Staging of Thyroid Cancer: Image Quality and Diagnostic Performance. AJR Am J Roentgenol. 2019;212(4):748–54. Epub 2019/03/23. doi: 10.2214/AJR.18.20334 . [DOI] [PubMed] [Google Scholar]
12.Ludes C, Labani A, Severac F, Jeung MY, Leyendecker P, Roy C, et al. Ultra-low-dose unenhanced chest CT: Prospective comparison of high kV/low mA versus low kV/high mA protocols. Diagn Interv Imaging. 2019;100(2):85–93. Epub 2018/12/19. doi: 10.1016/j.diii.2018.11.012 . [DOI] [PubMed] [Google Scholar]
13.MacDougall RD, Zhang Y, Callahan MJ, Perez-Rossello J, Breen MA, Johnston PR, et al. Improving Low-Dose Pediatric Abdominal CT by Using Convolutional Neural Networks. Radiol Artif Intell. 2019;1(6):e180087. Epub 2020/02/25. doi: 10.1148/ryai.2019180087 ; PubMed Central PMCID: PMC6884028. [DOI] [PMC free article] [PubMed] [Google Scholar]
14.Wang KC, Jones A, Kambhampati S, Gilotra MN, Liacouras PC, Stuelke S, et al. CT-Based 3D Printing of the Glenoid Prior to Shoulder Arthroplasty: Bony Morphology and Model Evaluation. J Digit Imaging. 2019;32(5):816–26. Epub 2019/03/02. doi: 10.1007/s10278-019-00177-4 ; PubMed Central PMCID: PMC6737174. [DOI] [PMC free article] [PubMed] [Google Scholar]
15.Kang HJ, Kim BS, Kim SM, Kim YM, Kim HN, Park JY, et al. Can Preoperative 3D Printing Change Surgeon’s Operative Plan for Distal Tibia Fracture? BioMed research international. 2019;2019:7059413. Epub 2019/03/20. doi: 10.1155/2019/7059413 ; PubMed Central PMCID: PMC6388342. [DOI] [PMC free article] [PubMed] [Google Scholar]
16.Chung KJ, Huang B, Choi CH, Park YW, Kim HN. Utility of 3D Printing for Complex Distal Tibial Fractures and Malleolar Avulsion Fractures. Foot Ankle Int. 2015;36(12):1504–10. doi: 10.1177/1071100715595695 [DOI] [PubMed] [Google Scholar]
17.Yang L, Shang XW, Fan JN, He ZX, Wang JJ, Liu M, et al. Application of 3D Printing in the Surgical Planning of Trimalleolar Fracture and Doctor-Patient Communication. BioMed research international. 2016;2016:2482086. Epub 2016/07/23. doi: 10.1155/2016/2482086 ; PubMed Central PMCID: PMC4947492. [DOI] [PMC free article] [PubMed] [Google Scholar]
18.Shim E, Kang Y, Ahn JM, Lee E, Lee JW, Oh JH, et al. Metal Artifact Reduction for Orthopedic Implants (O-MAR): Usefulness in CT Evaluation of Reverse Total Shoulder Arthroplasty. AJR Am J Roentgenol. 2017;209(4):860–6. Epub 2017/08/11. doi: 10.2214/AJR.16.17684 . [DOI] [PubMed] [Google Scholar]
19.Saltybaeva N, Jafari ME, Hupfer M, Kalender WA. Estimates of effective dose for CT scans of the lower extremities. Radiology. 2014;273(1):153–9. doi: 10.1148/radiol.14132903 . [DOI] [PubMed] [Google Scholar]
20.Khmelnitskaya E, Lamont LE, Taylor SA, Lorich DG, Dines DM, Dines JS. Evaluation and management of proximal humerus fractures. Adv Orthop. 2012;2012:861598. Epub 2013/01/15. doi: 10.1155/2012/861598 ; PubMed Central PMCID: PMC3535990. [DOI] [PMC free article] [PubMed] [Google Scholar]
21.Edwards JG, Clarke P, Pieracci FM, Bemelman M, Black EA, Doben A, et al. Taxonomy of multiple rib fractures: Results of the chest wall injury society international consensus survey. The journal of trauma and acute care surgery. 2020;88(2):e40–e5. Epub 2019/10/08. doi: 10.1097/TA.0000000000002282 . [DOI] [PubMed] [Google Scholar]
22.Goetti R, Baumüller S, Feuchtner G, Stolzmann P, Karlo C, Alkadhi H, et al. High-pitch dual-source CT angiography of the thoracic and abdominal aorta: is simultaneous coronary artery assessment possible? AJR Am J Roentgenol. 2010;194(4):938–44. Epub 2010/03/24. doi: 10.2214/AJR.09.3482 . [DOI] [PubMed] [Google Scholar]
23.Peng AW, Dardari ZA, Blumenthal RS, Dzaye O, Obisesan OH, Iftekhar Uddin SM, et al. Very High Coronary Artery Calcium (≥1000) and Association With Cardiovascular Disease Events, Non-Cardiovascular Disease Outcomes, and Mortality: Results From MESA. Circulation. 2021;143(16):1571–83. Epub 2021/03/03. doi: 10.1161/CIRCULATIONAHA.120.050545 ; PubMed Central PMCID: PMC8058297. [DOI] [PMC free article] [PubMed] [Google Scholar]
24.Alagic Z, Bujila R, Enocson A, Srivastava S, Koskinen SK. Ultra-low-dose CT for extremities in an acute setting: initial experience with 203 subjects. Skeletal Radiol. 2020;49(4):531–9. Epub 2019/09/11. doi: 10.1007/s00256-019-03309-7 ; PubMed Central PMCID: PMC7021773. [DOI] [PMC free article] [PubMed] [Google Scholar]
25.Cianci R, Delli Pizzi A, Esposito G, Timpani M, Tavoletta A, Pulsone P, et al. Ultra-low dose CT colonography with automatic tube current modulation and sinogram-affirmed iterative reconstruction: Effects on radiation exposure and image quality. J Appl Clin Med Phys. 2019;20(1):321–30. Epub 2018/12/27. doi: 10.1002/acm2.12510 ; PubMed Central PMCID: PMC6333183. [DOI] [PMC free article] [PubMed] [Google Scholar]
26.Zhao L, Bao J, Guo Y, Li J, Yang X, Lv T, et al. Ultra-low dose one-step CT angiography for coronary, carotid and cerebral arteries using 128-slice dual-source CT: A feasibility study. Exp Ther Med. 2019;17(5):4167–75. Epub 2019/04/17. doi: 10.3892/etm.2019.7420 ; PubMed Central PMCID: PMC6447913. [DOI] [PMC free article] [PubMed] [Google Scholar]

PLoS One. doi: 10.1371/journal.pone.0275297.r001

Decision Letter 0

Jonas Bianchi

22 Apr 2022

PONE-D-22-07553The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing modelsPLOS ONE

Dear Dr. Xiao,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Jun 05 2022 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Jonas Bianchi, DDD, MS, Ph.D

Academic Editor

PLOS ONE

Journal Requirements:

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. We note that you have indicated that data from this study are available upon request. PLOS only allows data to be available upon request if there are legal or ethical restrictions on sharing data publicly. For more information on unacceptable data access restrictions, please see http://journals.plos.org/plosone/s/data-availability#loc-unacceptable-data-access-restrictions.

In your revised cover letter, please address the following prompts:

a) If there are ethical or legal restrictions on sharing a de-identified data set, please explain them in detail (e.g., data contain potentially sensitive information, data are owned by a third-party organization, etc.) and who has imposed them (e.g., an ethics committee). Please also provide contact information for a data access committee, ethics committee, or other institutional body to which data requests may be sent.

b) If there are no restrictions, please upload the minimal anonymized data set necessary to replicate your study findings as either Supporting Information files or to a stable, public repository and provide us with the relevant URLs, DOIs, or accession numbers. For a list of acceptable repositories, please see http://journals.plos.org/plosone/s/data-availability#loc-recommended-repositories.

We will update your Data Availability statement on your behalf to reflect the information you provide.

Additional Editor Comments:

Thank you for submitting your paper for consideration.

Please, see some points that needs major revision.

1. Please, state the hypothesis of your study (null and/or alternative)

2. Please, add the sample size calculation and study power of your data.

3. ". Assessment of clinical performance on the diagnosis and surgical planning by using 3D printing models created from low-dose CT images has not been reported in published studies."

Are you sure about this information? What are you referring to here? I can find many studies on related topics. Please, be more specific.

4. Was the 0.5 slice thickness, but and the other dimensions? please provide the resolution for each dimension of your voxel.

5. "Patients’ 3D models of shoulder joints were reconstructed from the original CT data stored in DICOM format by using Vitrea fX"...

What is this? You need to use either a reference or named it with the name of the software, company, state, country etc.,

6. What was the resolution of the printed models in x,y and z? this information is essential to your paper.

7. "Two senior radiologists, with over 10 years of clinical experience and who were blinded to the results, performed quality assessment of CT images..."

What do you mean to say by senior? Were those radiologists part of a national board of radiologists? Faculty? Researchers? Clinicians? I need to know how to asses their expertise, rather than "senior"

8. "hey were blinded to the scanning parameters and rated the image quality based on a 3-point score system developed by published studies"

Please, specify which study using references.

9. " A 3-point rating system developed by published studies was employed for the assessment"

Same comment as before. If the study that you're referring to is the number 5, is this study (5) a validation study? It seems to be a validation study because you are using it as gold standard for your scores.

10. Statistical analysis:

Please, in addition to the ICC add a Bland-Altman test for inter-observer agreement for each group.

11. "Three-dimension printing models of the shoulder joint created from ultra-low-dose CT scans can be used in the surgical planning of specific bones like the clavicle but perform insufficiently in the overall surgical planning for shoulder injuries due to the significant

geometric flaws "

I don`t see that yous study has proven the hypothesis that it can be used for surgical planning, since you have not tested this. Please, re-write your conclusions in the paper and abstract based on your results only.

12. "Gold standard of diagnosis performance: The gold standard of diagnosis performance is surgical findings or computed tomography/Diagnostic Radiology re-examination"

Please, provide more information, references, and how the gold standard was performed

13: "Radiation dose must increase to obtain high-definition CT images for developing accurate 3D printing models."

This is a general idea, that should be state with caution, and not as an affirmation.

14: Tables: The table names needs to contain the statistical test that you did. None of them has this information. "P<0.05 means statistically significant" should go in the footnote.

Your ANOVA table contains no letters to distinguish differences between and among groups.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Congratulations for the work, I believe that its relevance is justified as it seeks a way to reduce the radiation dose for patients and at the same time obtain a good diagnosis on a day-to-day basis.

- On the first paragraph of the introduction after the sentence “The dose of 50 radiation for traditional CT on a shoulder joint is extremely high with 5.28 mSv in 51 comparison to conventional radiography, which is less than 0.011 mSv...” I suggest adding the information of why you are studying the ultra-low dose CT and why it is so important to try to reduce the radiation dose in patients. Suggested references to justify the importance of studying the ultra-low dose protocol of CT:

o Oestreich AE. RSNA centennial article: ALARA 1912: "As low a dose as possible" a century ago. Radiographics. 2014 Sep-Oct;34(5):1457-60. doi: 10.1148/rg.345130136. PMID: 25208291.

o Mathews JD, Forsythe AV, Brady Z, Butler MW, Goergen SK, Byrnes GB, Giles GG, Wallace AB, Anderson PR, Guiver TA, McGale P, Cain TM, Dowty JG, Bickerstaffe AC, Darby SC. Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ. 2013 May 21;346:f2360. doi: 10.1136/bmj.f2360. PMID: 23694687; PMCID: PMC3660619.

- The section “Patient selection”: Why did you include patients with osteoporosis in your study? As the bone density is altered in these individuals and their CT image can be different (or worse) from individuals without osteoporosis.

- “Preparation of three-dimensional models”: In this section, information about the 3D printing method was missing, such as: type of 3D printing, reason for choosing this type of printing, diameter of the polylactic acid filament. The printing method was by extrusion (FDM) in your study, as I understand it, but we know that the printing quality using the Digital Lighting Process (DLP) method with vat polymerization is more accurate and faster (although it is more expensive). By adding this information, you can cite Eltes et al.1 study that compared 3D physical models printed with FDM or DLP, and demonstrated that the surface qualities, measured by roughness are adequate (~99% of values <0.1 mm) for both physical models, for their anatomic region. So, this justifies your choice for FDM 3D printing process. But, as in your article the printing was of low quality for some regions, it might be interesting for a next approach to try another type of 3D printing with greater precision (DLP, for example), for those regions that did not perform well with ultra-low dose CT 3D models.

o 1- Eltes, PE, Kiss, L, Bartos, M, et al. Geometrical accuracy evaluation of an affordable 3D printing technology for spine physical models. J Clin Neurosci 2020; 72: 438–446.

- “Types of fractures in each group” section: Although the term comminuted fracture is generally understood, it would be interesting to briefly define the term after mentioning it for the first time.

- Lines 145 and 155: You mention the 3-point score system developed by “published studies”, but you only cite one study. If there are other studies, you must cite more then one (you cited only one – reference 5), and if you want to cite only this reference (5), then you should put this statement in the singular.

- Discussion section:

o Line 223: You mention “Experimental results”, which are they? What is the reference for this affirmation?

o In your study, the ultra-low-dose protocol of the scapula and humerus on the 3D-printed model was inapplicable to clinical planning and failed its clinical application. Xiao et al.2, in 2021, obtained 3D printing models that, despite the quality being lower in the ultra-low dose group, were still sufficient to contribute to the preoperative evaluation and study, the diagnostic performance was not affected by the ultra-low dose protocol.

To what do you attribute this difference between studies? Do you attribute to the different anatomical regions being studied and their particularities? It would be interesting to add information like this to the discussion.

2- Xiao M, Zhang M, Lei M, Hu X, Wang Q, Chen Y, et al. Application of ultra-low dose CT in 3D printing of distal radial fractures. Eur J Radiol. 2021;135:109488. Epub 2021/01/02. doi: 10.1016/j.ejrad.2020.109488. PubMed PMID: 33385624.

o Line 271:

FDM 3D printing, especially of large anatomical regions like the shoulder, take time, however, in terms of cost, it is currently much more affordable and 3D printing by extrusion (FDM) is the cheapest of all 3D printing. The advantage that 3D printing offers for this type of fracture, in terms of diagnosis and treatment accuracy, does it not outweigh the costs of 3D printing? I suggest you address this in the discussion. For example, Guochen Luo et al.3, for their anatomic region of interest, observed the following advantages from 3D printing technology assistance: less trauma, short operation time, less bleeding and reducing the difficulty of operation, which can reduce the waste of bone graft, and more complete reconstruction of the anatomical structure of the defective bone.

3- Luo G, Zhang Y, Wang X, Chen S, Li D, Yu M. Individualized 3D printing-assisted repair and reconstruction of neoplastic bone defects at irregular bone sites: exploration and practice in the treatment of scapular aneurysmal bone cysts. BMC Musculoskelet Disord. 2021 Nov 25;22(1):984. doi: 10.1186/s12891-021-04859-5. PMID: 34

Reviewer #2: This manuscript describes The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models.

I have some comments.

Material and Methods

patient selection

1.line 87. “osteoporosis (bone density: lumbar spine and/or hip joint T> -2.5).” . I think this is the definition of normal bone and osteopenia It could be write non-osteoporosis.

2.line 88, 90 “ T> -2.5” “ T< -2.5” . It could be write as “T-score > -2.5, T-score< -2.5”

3. How about the pathological fracture patient? Were these patients included in the study?

Types of fractures in each group

line 125. I think the definition of “avulsion fracture” means bone was avulsed by the ligament or tendon insertion. This description maybe confused by the reader. Please clarify this description.

line 127. I think the definition of “dislocation” means the relationship of the joint. It could be write as “ displacement of the bone cortex”.

Results

line 197. “ (Table 2)” should be “(Table 3)”, please check it

Table 1

Age (year) “ ±” is redundant

Gender Dose the author mean male/female 15/15 10/20 13/20? Please clarify

Normal bone 14/16, 11/19/13/20, this description was confused by the reader, please clarify

Reviewer #3: - The manuscript raises an interesting topic, but some corrections may make the information clearer.

- In the abstract it is described that the patients were randomly divided into two groups (standard-dose and ultra-low-dose groups), although in the materials and methods three are described. Please correct this information.

- I suggest reviewing Table 01, there are different types of information. Please make it clearer.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PLoS One. 2022 Sep 26;17(9):e0275297. doi: 10.1371/journal.pone.0275297.r002

Author response to Decision Letter 0

21 Jul 2022

Dear Dr. Bianchi,

Thank you very much for your decision letter and advice on our manuscript (Manuscript No. PONE-D-22-07553) entitled “The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models”. We also thank the reviewers for the constructive comments and suggestions. We have revised the manuscript accordingly, and all amendments are indicated by red font in the revised manuscript. In addition, our point-by-point responses to the comments are listed below this letter.

This revised manuscript has been edited and proofread by Medjaden Inc..

We hope that our revised manuscript is now acceptable for publication in your journal and look forward to hearing from you soon.

With best wishes,

Yours sincerely,

Mengqiang Xiao

First of all, we would like to express our sincere gratitude to the reviewers for their constructive and positive comments.

Please, see some points that needs major revision.

1. Please, state the hypothesis of your study (null and/or alternative)

Response: The following sentence was added in the Introduction section.

“We hypothesize that low dose CT scans meet the clinical needs for fracture diagnosis and 3D printing models.”

2. Please, add the sample size calculation and study power of your data.

Response: The following sentences were added in the Methods section.

“Sample size determination

The sample size was calculated using the G*Power software for a priori analysis, with a sensitivity of 95% (�=0.05) and a study power of 90% (β=0.10). Since the patients were classified into three groups based on the dose, the effect size was determined by a one-way analysis of variance (ANOVA) using the effect size measure Cohen’s f. The resulting sample size n is 12. If 10% missing values were defined, the sample size (n=15 per group) is sufficient for the study.”

3. ". Assessment of clinical performance on the diagnosis and surgical planning by using 3D printing models created from low-dose CT images has not been reported in published studies."

Are you sure about this information? What are you referring to here? I can find many studies on related topics. Please, be more specific.

Response: We only found one paper that reported the use of 3D printed models created from low-dose CT images to evaluate the clinical performance of diagnosis and surgical planning. The sentence was changed as follows:

“Xiao et al. reported that 3D printed models created from low-dose CT images effectively evaluate the clinical performance of diagnosis and surgical planning. However, assessment of clinical performance on the diagnosis and surgical planning by using 3D printing models created from low-dose shoulder CT images has not been studied.”

Reference:

Xiao MQ , Zhang M , Lei M , et al. Application of ultra-low-dose CT in 3D printing of distal radial fractures. Eur J Radiol, 2020. 135: p. 109488. DOI：10.1016/j.ejrad.2020.109488

4. Was the 0.5 slice thickness, but and the other dimensions? please provide the resolution for each dimension of your voxel.

Response: In this study, we used 0.5 mm slice thickness (Table 1).

5. "Patients’ 3D models of shoulder joints were reconstructed from the original CT data stored in DICOM format by using Vitrea fX"...

What is this? You need to use either a reference or named it with the name of the software, company, state, country etc.,

Response: The sentence was changed as follows: “Patients’ 3D models of shoulder joints were reconstructed from the original CT data stored in DICOM format by using the Vitrea fX software (Vitrea2，Canon, Japan).”

6. What was the resolution of the printed models in x,y and z? this information is essential to your paper.

Response: The following sentence was added:

“The resolution of the printed models was 0.011 mm � 0.011 mm � 0.0025 mm.”

7. "Two senior radiologists, with over 10 years of clinical experience and who were blinded to the results, performed quality assessment of CT images..."

Response: The following sentences were added.

“Two senior radiologists, who were part of a national board of radiologists and were clinicians with over 10 years of clinical experience for clinical diagnosis of musculoskeletal diseases performed quality assessment of CT images. They were blinded to the results of the study.”

8. "hey were blinded to the scanning parameters and rated the image quality based on a 3-point score system developed by published studies"

Please, specify which study using references.

Response: The sentence was changed as follows: “They were blinded to the scanning parameters and rated the image quality based on a 3-point score system as previously reported”

Reference

Xiao MQ , Zhang M , Lei M , et al. Application of ultra-low-dose CT in 3D printing of distal radial fractures. Eur J Radiol, 2020. 135: p. 109488. DOI: 10.1016/j.ejrad.2020.109488

9. "A 3-point rating system developed by published studies was employed for the assessment"

Response: The same paper (ref 5) was cited.

The 3-point method is the scoring system used by the team before, and it is also widely used by other studies.

Reference

Xiao MQ , Zhang M , Lei M , et al. Application of ultra-low-dose CT in 3D printing of distal radial fractures. Eur J Radiol, 2020. 135: p. 109488. DOI: 10.1016/j.ejrad.2020.109488)

10. Statistical analysis:

Please, in addition to the ICC add a Bland-Altman test for inter-observer agreement for each group.

Response: Graded variables were used to test ICC. Classified data can not use Kendall Bland-Altman test.

Response:

Three-dimension printing models of the shoulder joint created from ultra-low-dose CT scans can be used in the surgical planning of specific bones like the clavicle and nearly 94% of the clavicle models reached the adequate level. However, they performed insufficiently in the overall surgical planning for shoulder blade due to the significant geometric flaws with only 27% of the clavicle models reaching the adequate level.

12. "Gold standard of diagnosis performance: The gold standard of diagnosis performance is surgical findings or computed tomography/Diagnostic Radiology re-examination"

Please, provide more information, references, and how the gold standard was performed

Response: The following sentences were added.

“For fractures treated with surgery, the diagnosis was made by observing the fracture directly during surgery. For fractures by expectant treatment of fractures, the diagnosis was made based on the CT/DR review within 1-3 months: callus at the fracture end; dysplasia or old fracture without callus.”

13: "Radiation dose must increase to obtain high-definition CT images for developing accurate 3D printing models."

This is a general idea that should be state with caution, and not as an affirmation.

Response: The sentence was changed as follows:

“Radiation dose should increase in order to obtain high-definition CT images for developing accurate 3D printing models.”

14: Tables: The table names needs to contain the statistical test that you did. None of them has this information. "P < 0.05 means statistically significant" should go in the footnote.

Your ANOVA table contains no letters to distinguish differences between and among groups.

Response: Statistical significant differences were distinguished by letters (a, b, and c) in the tables

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

________________________________________

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

________________________________________

3. Have the authors made all data underlying the findings in their manuscript fully available?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

________________________________________

4. Is the manuscript presented in an intelligible fashion and written in standard English?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

________________________________________

Response: Thanks for the positive comments.

5. Review Comments to the Author

Oestreich AE. RSNA centennial article: ALARA 1912: "As low a dose as possible" a century ago. Radiographics. 2014 Sep-Oct;34(5):1457-60. doi: 10.1148/rg.345130136. PMID: 25208291.

Mathews JD, Forsythe AV, Brady Z, Butler MW, Goergen SK, Byrnes GB, Giles GG, Wallace AB, Anderson PR, Guiver TA, McGale P, Cain TM, Dowty JG, Bickerstaffe AC, Darby SC. Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ. 2013 May 21;346:f2360. doi: 10.1136/bmj.f2360. PMID: 23694687; PMCID: PMC3660619.

Response: The following sentences were added in the Introduction section.

“The risk of increased ionizing radiation exposure is the primary safety concern for having a CT scan. According to the data collected in the United States from 1991 to 1996, malignant tumors caused by CT radiation account for 0.4% of all malignant tumors.”

Response: The patients with osteoporosis were not included in the study. It is a typo, and was corrected as follows: “….non-osteoporosis (bone density: lumbar spine and/or hip joint T-score > -2.5).”

o 1- Eltes, PE, Kiss, L, Bartos, M, et al. Geometrical accuracy evaluation of an affordable 3D printing technology for spine physical models. J Clin Neurosci 2020; 72: 438–446.

Response: The conventional orthopaedic surgery system does not have high requirements for 3D printing accuracy, which is enough to reach 0.1 mm, and extrusion 3D printing (FDM) is the cheapest of all 3D printing, which can meet the demand.

Response: The sentence was changed as follows:

“In this study, shoulder fractures were divided into simple fractures and comminuted fractures (defined as fractures in which the bone was broken with 3 or more pieces) in terms of the strategy of treatment.”

Response: The following references were cited.

Goetti R, Baumüller S, Feuchtner G, et al. High-pitch dual-source CT angiography of the thoracic and abdominal aorta: is simultaneous coronary artery assessment possible? [J]. American Journal of Roentgenology, 2010, 194(4): 938-944.

Peng A W, Dardari Z A, Blumenthal R S, et al. Very high coronary artery calcium (≥ 1000) and association with cardiovascular disease events, non–cardiovascular disease outcomes, and mortality: results from MESA [J]. Circulation, 2021, 143(16): 1571-1583.

- Discussion section:

o Line 223: You mention “Experimental results”, which are they? What is the reference for this affirmation?

Response: The following sentences were added.

“We have previously demonstrated that the quality of CT images at the wrist joint meet the needs of clinical fracture diagnosis and the image quality of the 3D model created from ultra-low-dose CT scans is good enough for the surgical planning. However, in terms of the scapula part of the shoulder joint, the image quality of ultra-low dose CT meets the needs of clinical fracture diagnosis, but the image quality of the 3D model is too low poor for the surgical planning.”

According to our previous lumbar spine model, low-dose 3D printing model of the wrist joint, and this study, we speculate that it is related to the thickness of the cortical bone. Thicker cortical bone reduces image quality, and the boundary with the surrounding muscles is still clear. The cortical bone of the scapula body is thin, and the bone cortex of the clavicle wrist joint and lumbar vertebrae model is relatively thick. The image quality of the clavicle 3D printing model is better.

o Line 271:

Response: The conventional orthopaedic surgery system does not have high requirements for 3D printing accuracy, which is enough to reach 0.1 mm. Extrusion 3D printing (FDM) is the cheapest of all 3D printing, and the 3D printing accuracy is 0.011 mm, which fully meets the demand. Higher precision 3D printing has too high cost and is not conducive to the research. The high cost made it difficult for 3D printing technology to be popularized in hospitals. The relatively low-cost material PLA (Tianwei Co., Ltd., US $9.83 for 1KG PLA material) was used in this study. Printing one 3D model costs about $2.16 and takes about 15.51 ± 1.20 hours. In our study, 3D printing process self-study videos were provided by 3D printing manufacturers, and 3D modeling parameters were adjusted remotely by the manufacturers. Ordinary computers could run the software, which was easy to learn.

Reviewer #2: This manuscript describes The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models.

I have some comments.

Material and Methods

patient selection

1.line 87. “osteoporosis (bone density: lumbar spine and/or hip joint T > -2.5).” . I think this is the definition of normal bone and osteopenia It could be write non-osteoporosis.

Response: Changed as suggested as follows: “non-osteoporosis (bone density: lumbar spine and/or hip joint T-score > -2.5)”.

2.line 88, 90 “T > -2.5” “T < -2.5”. It could be write as “T-score > -2.5, T-score < -2.5”

Response: Changed as suggested.

3. How about the pathological fracture patient? Were these patients included in the study?

Types of fractures in each group

Response:

line 125. I think the definition of “avulsion fracture” means bone was avulsed by the ligament or tendon insertion. This description maybe confused by the reader. Please clarify this description.

Response: The sentence was changed as follows:

“Avulsion fractures refer to avulsion fractures caused by a sudden and violent contraction of a muscle or ligament, resulting in a long-diameter low than 5 mm wide bone piece.”

line 127. I think the definition of “dislocation” means the relationship of the joint. It could be write as “displacement of the bone cortex”.

Response: Changed as suggested.

Results

line 197. “(Table 2)” should be “(Table 3)”, please check it

Response: Changed as suggested.

Table 1

Age (year) “±” is redundant

Gender Dose the author mean male/female 15/15 10/20 13/20? Please clarify

Normal bone 14/16, 11/19/13/20, this description was confused by the reader, please clarify

Response: Table 1 was changed in the revised manuscript.

Reviewer #3: - The manuscript raises an interesting topic, but some corrections may make the information clearer.

Response: The sentence was changed as follows: “A total of 93 patients with displaced shoulder fractures were randomly divided into standard-dose, low-dose groups and ultra-low-dose groups.”

- I suggest reviewing Table 01, there are different types of information. Please make it clearer.

Response: Table 1 was changed in the revised manuscript.

Attachment

Submitted filename: PONE-D-22-07553_Response letter.doc

Click here for additional data file.^{(62KB, doc)}

PLoS One. doi: 10.1371/journal.pone.0275297.r003

Decision Letter 1

Jonas Bianchi

18 Aug 2022

PONE-D-22-07553R1

The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models

PLOS ONE

Dear Dr. Xiao,

Please submit your revised manuscript by Oct 02 2022 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

We look forward to receiving your revised manuscript.

Kind regards,

Jonas Bianchi, DDD, MS, Ph.D

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Reviewer #1: (No Response)

Reviewer #2: This manuscript describes the clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models.

I have two comments.

(1). Material and Methods: patient selection

How about the pathological fracture patient? Were these patients included in the study? The authors did not answer this question.

(2). line 143-147 : ” Displaced fractures refer to avulsion fractures caused by a sudden and violent contraction of a muscle or ligament, resulting in a long-diameter low than 5 mm wide bone piece. Non-displaced fractures are defined as no angulation or shortening, less than 2 mm wide fracture line and/or less than 1 mm displacement of the bone cortex [21].”

This description will still confuse the reader. Please clarify the definition. Displaced fracture is not equal to the avulsion fracture. How much displacement (distance) or angulation (angle) was defined as displaced fracture in this study? Please clarify the definition.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

**********

PLoS One. 2022 Sep 26;17(9):e0275297. doi: 10.1371/journal.pone.0275297.r004

Author response to Decision Letter 1

26 Aug 2022

Dear Dr. Bianchi,

This revised manuscript has been edited and proofread by Medjaden Inc..

We hope that our revised manuscript is now acceptable for publication in your journal and look forward to hearing from you soon.

With best wishes,

Yours sincerely,

Mengqiang Xiao

First of all, we would like to express our sincere gratitude to the reviewers for their constructive and positive comments.

Reviewer #2: This manuscript describes the clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models.

I have two comments.

(1). Material and Methods: patient selection

How about the pathological fracture patient? Were these patients included in the study? The authors did not answer this question.

Response: Patients with pathological fractures were not included in the study. The following sentences were added to the Materials and Methods section.

“Exclusion criteria were as follows: less than 18 years of age, pregnancy, patients who refused to participate in the study, and patients with osteoporosis (bone density: lumbar spine and/or hip joint T-score < -2.5) or pathological fractures.”

(2). line 143-147:” Displaced fractures refer to avulsion fractures caused by a sudden and violent contraction of a muscle or ligament, resulting in a long-diameter low than 5 mm wide bone piece. Non-displaced fractures are defined as no angulation or shortening, less than 2 mm wide fracture line and/or less than 1 mm displacement of the bone cortex [21].”

Response: The following sentences were added.

Line 143-147: “Non-displaced fractures are defined as having no angulation or shortening, a fracture line less than 2 mm wide and/or less than 1 mm displacement of the bone cortex. Displaced fractures are defined as having a fracture line more than 2 mm wide and/or more than 1 mm displacement of the bone cortex. Avulsion fractures caused by a sudden and violent contraction of a muscle or ligament, were grouped into non-displaced fractures or displaced fractures when the fracture had a long-diameter � 5 mm or > 5 mm wide bone piece, respectively [21].”

Attachment

Submitted filename: PONE-D-22-07553_Response letter.docx

Click here for additional data file.^{(15.9KB, docx)}

PLoS One. doi: 10.1371/journal.pone.0275297.r005

Decision Letter 2

Jonas Bianchi

13 Sep 2022

The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models

PONE-D-22-07553R2

Dear Dr. Xiao,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Jonas Bianchi, DDD, MS, Ph.D

Academic Editor

PLOS ONE

Reviewer's Responses to Questions

Comments to the Author

Reviewer #2: All comments have been addressed

PLoS One. doi: 10.1371/journal.pone.0275297.r006

Acceptance letter

Jonas Bianchi

16 Sep 2022

PONE-D-22-07553R2

The clinical performance of ultra-low-dose shoulder CT scans: the assessment on image and physical 3D printing models

Dear Dr. Xiao:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Jonas Bianchi

Academic Editor

PLOS ONE

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

S1 Checklist

(DOC)

Click here for additional data file.^{(196.5KB, doc)}

S1 File

(PDF)

Click here for additional data file.^{(128.3KB, pdf)}

Attachment

Submitted filename: PONE-D-22-07553_Response letter.doc

Click here for additional data file.^{(62KB, doc)}

Attachment

Submitted filename: PONE-D-22-07553_Response letter.docx

Click here for additional data file.^{(15.9KB, docx)}

Data Availability Statement

[pone.0275297.ref001] 1.Amini B, Beckmann NM, Beaman FD, Wessell DE, Bernard SA, Cassidy RC, et al. ACR Appropriateness Criteria(®) Shoulder Pain-Traumatic. J Am Coll Radiol. 2018;15(5s):S171–s88. Epub 2018/05/05. doi: 10.1016/j.jacr.2018.03.013 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref002] 2.Ozaki R, Nakagawa S, Mizuno N, Mae T, Yoneda M. Hill-sachs lesions in shoulders with traumatic anterior instability: evaluation using computed tomography with 3-dimensional reconstruction. Am J Sports Med. 2014;42(11):2597–605. Epub 2014/09/19. doi: 10.1177/0363546514549543 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref003] 3.Yi JW, Park HJ, Lee SY, Rho MH, Hong HP, Choi YJ, et al. Radiation dose reduction in multidetector CT in fracture evaluation. Br J Radiol. 2017;90(1077):20170240. Epub 2017/07/15. doi: 10.1259/bjr.20170240 ; PubMed Central PMCID: PMC5858798. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref004] 4.Singh T, Muscroft N, Collier N, England A. A comparison of effective dose and risk for different collimation options used in AP shoulder radiography. Radiography (Lond). 2021. Epub 2021/12/11. doi: 10.1016/j.radi.2021.11.007 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref005] 5.Azman RR, Shah MNM, Ng KH. Radiation Safety in Emergency Medicine: Balancing the Benefits and Risks. Korean journal of radiology. 2019;20(3):399–404. Epub 2019/02/26. doi: 10.3348/kjr.2018.0416 ; PubMed Central PMCID: PMC6389812. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref006] 6.Ron E. Cancer risks from medical radiation. Health Phys. 2003;85(1):47–59. Epub 2003/07/11. doi: 10.1097/00004032-200307000-00011 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref007] 7.Oestreich AE. RSNA centennial article: ALARA 1912: "As low a dose as possible" a century ago. Radiographics. 2014;34(5):1457–60. Epub 2014/09/11. doi: 10.1148/rg.345130136 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref008] 8.Mathews JD, Forsythe AV, Brady Z, Butler MW, Goergen SK, Byrnes GB, et al. Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ. 2013;346:f2360. Epub 2013/05/23. doi: 10.1136/bmj.f2360 ; PubMed Central PMCID: PMC3660619 at www.icmje.org/coi_disclosure.pdf and declare: support from the Australian government (via the National Health and Medical Research Council, salary support from the Cancer Research Campaign UK and other agencies) for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref009] 9.Xiao M, Zhang M, Lei M, Hu X, Wang Q, Chen Y, et al. Application of ultra-low-dose CT in 3D printing of distal radial fractures. Eur J Radiol. 2021;135:109488. Epub 2021/01/02. doi: 10.1016/j.ejrad.2020.109488 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref010] 10.Hamard A, Greffier J, Bastide S, Larbi A, Addala T, Sadate A, et al. Ultra-low-dose CT versus radiographs for minor spine and pelvis trauma: a Bayesian analysis of accuracy. Eur Radiol. 2021;31(4):2621–33. Epub 2020/10/10. doi: 10.1007/s00330-020-07304-8 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref011] 11.Yeom JA, Roh J, Jeong YJ, Lee JC, Kim HY, Suh YJ, et al. Ultra-Low-Dose Neck CT With Low-Dose Contrast Material for Preoperative Staging of Thyroid Cancer: Image Quality and Diagnostic Performance. AJR Am J Roentgenol. 2019;212(4):748–54. Epub 2019/03/23. doi: 10.2214/AJR.18.20334 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref012] 12.Ludes C, Labani A, Severac F, Jeung MY, Leyendecker P, Roy C, et al. Ultra-low-dose unenhanced chest CT: Prospective comparison of high kV/low mA versus low kV/high mA protocols. Diagn Interv Imaging. 2019;100(2):85–93. Epub 2018/12/19. doi: 10.1016/j.diii.2018.11.012 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref013] 13.MacDougall RD, Zhang Y, Callahan MJ, Perez-Rossello J, Breen MA, Johnston PR, et al. Improving Low-Dose Pediatric Abdominal CT by Using Convolutional Neural Networks. Radiol Artif Intell. 2019;1(6):e180087. Epub 2020/02/25. doi: 10.1148/ryai.2019180087 ; PubMed Central PMCID: PMC6884028. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref014] 14.Wang KC, Jones A, Kambhampati S, Gilotra MN, Liacouras PC, Stuelke S, et al. CT-Based 3D Printing of the Glenoid Prior to Shoulder Arthroplasty: Bony Morphology and Model Evaluation. J Digit Imaging. 2019;32(5):816–26. Epub 2019/03/02. doi: 10.1007/s10278-019-00177-4 ; PubMed Central PMCID: PMC6737174. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref015] 15.Kang HJ, Kim BS, Kim SM, Kim YM, Kim HN, Park JY, et al. Can Preoperative 3D Printing Change Surgeon’s Operative Plan for Distal Tibia Fracture? BioMed research international. 2019;2019:7059413. Epub 2019/03/20. doi: 10.1155/2019/7059413 ; PubMed Central PMCID: PMC6388342. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref016] 16.Chung KJ, Huang B, Choi CH, Park YW, Kim HN. Utility of 3D Printing for Complex Distal Tibial Fractures and Malleolar Avulsion Fractures. Foot Ankle Int. 2015;36(12):1504–10. doi: 10.1177/1071100715595695 [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref017] 17.Yang L, Shang XW, Fan JN, He ZX, Wang JJ, Liu M, et al. Application of 3D Printing in the Surgical Planning of Trimalleolar Fracture and Doctor-Patient Communication. BioMed research international. 2016;2016:2482086. Epub 2016/07/23. doi: 10.1155/2016/2482086 ; PubMed Central PMCID: PMC4947492. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref018] 18.Shim E, Kang Y, Ahn JM, Lee E, Lee JW, Oh JH, et al. Metal Artifact Reduction for Orthopedic Implants (O-MAR): Usefulness in CT Evaluation of Reverse Total Shoulder Arthroplasty. AJR Am J Roentgenol. 2017;209(4):860–6. Epub 2017/08/11. doi: 10.2214/AJR.16.17684 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref019] 19.Saltybaeva N, Jafari ME, Hupfer M, Kalender WA. Estimates of effective dose for CT scans of the lower extremities. Radiology. 2014;273(1):153–9. doi: 10.1148/radiol.14132903 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref020] 20.Khmelnitskaya E, Lamont LE, Taylor SA, Lorich DG, Dines DM, Dines JS. Evaluation and management of proximal humerus fractures. Adv Orthop. 2012;2012:861598. Epub 2013/01/15. doi: 10.1155/2012/861598 ; PubMed Central PMCID: PMC3535990. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref021] 21.Edwards JG, Clarke P, Pieracci FM, Bemelman M, Black EA, Doben A, et al. Taxonomy of multiple rib fractures: Results of the chest wall injury society international consensus survey. The journal of trauma and acute care surgery. 2020;88(2):e40–e5. Epub 2019/10/08. doi: 10.1097/TA.0000000000002282 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref022] 22.Goetti R, Baumüller S, Feuchtner G, Stolzmann P, Karlo C, Alkadhi H, et al. High-pitch dual-source CT angiography of the thoracic and abdominal aorta: is simultaneous coronary artery assessment possible? AJR Am J Roentgenol. 2010;194(4):938–44. Epub 2010/03/24. doi: 10.2214/AJR.09.3482 . [DOI] [PubMed] [Google Scholar]

[pone.0275297.ref023] 23.Peng AW, Dardari ZA, Blumenthal RS, Dzaye O, Obisesan OH, Iftekhar Uddin SM, et al. Very High Coronary Artery Calcium (≥1000) and Association With Cardiovascular Disease Events, Non-Cardiovascular Disease Outcomes, and Mortality: Results From MESA. Circulation. 2021;143(16):1571–83. Epub 2021/03/03. doi: 10.1161/CIRCULATIONAHA.120.050545 ; PubMed Central PMCID: PMC8058297. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref024] 24.Alagic Z, Bujila R, Enocson A, Srivastava S, Koskinen SK. Ultra-low-dose CT for extremities in an acute setting: initial experience with 203 subjects. Skeletal Radiol. 2020;49(4):531–9. Epub 2019/09/11. doi: 10.1007/s00256-019-03309-7 ; PubMed Central PMCID: PMC7021773. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref025] 25.Cianci R, Delli Pizzi A, Esposito G, Timpani M, Tavoletta A, Pulsone P, et al. Ultra-low dose CT colonography with automatic tube current modulation and sinogram-affirmed iterative reconstruction: Effects on radiation exposure and image quality. J Appl Clin Med Phys. 2019;20(1):321–30. Epub 2018/12/27. doi: 10.1002/acm2.12510 ; PubMed Central PMCID: PMC6333183. [DOI] [PMC free article] [PubMed] [Google Scholar]

[pone.0275297.ref026] 26.Zhao L, Bao J, Guo Y, Li J, Yang X, Lv T, et al. Ultra-low dose one-step CT angiography for coronary, carotid and cerebral arteries using 128-slice dual-source CT: A feasibility study. Exp Ther Med. 2019;17(5):4167–75. Epub 2019/04/17. doi: 10.3892/etm.2019.7420 ; PubMed Central PMCID: PMC6447913. [DOI] [PMC free article] [PubMed] [Google Scholar]

PERMALINK

The clinical performance of ultra-low-dose shoulder CT scans: The assessment on image and physical 3D printing models

Ming Lei

Meng Zhang

Niyuan Luo

Jingzhi Ye

Fenghuan Lin

Yanxia Chen

Jun Chen

Mengqiang Xiao

Roles

Abstract

Objectives

Materials and methods

Results

Conclusion

Introduction

Materials and methods

Patient selection

Table 1. CT parameters and patient information of each group.

Sample size determination

Image acquisition

Preparation of three-dimensional models

Types of fractures in each group

Assessment of image quality

Fig 1. A 51-year-old man with a left clavicle fracture underwent a standard-dose CT scan.

Fig 2. A 49-year-old man with a left clavicle fracture underwent a low-dose CT scan.

Fig 3. A 58-year-old man with a scapula body linear fracture underwent an ultra-low-dose CT scan.

Fig 4. A 65-year-old female with a left clavicle comminuted fracture underwent an ultra-low-dose CT scan.

Assessment of three-dimensional printing models quality

Gold standard of diagnosis performance

Statistical analysis

Results

Table 2. Objective image evaluation of the different groups.

Table 3. Subjective evaluation of the different groups.

Discussion

Conclusions

Supporting information

Data Availability

Funding Statement

References

Decision Letter 0

Jonas Bianchi

Roles

Author response to Decision Letter 0

Decision Letter 1

Jonas Bianchi

Roles

Author response to Decision Letter 1

Decision Letter 2

Jonas Bianchi

Roles

Acceptance letter

Jonas Bianchi

Roles

Associated Data

Supplementary Materials

Data Availability Statement

ACTIONS

PERMALINK

RESOURCES

Similar articles

Cited by other articles

Links to NCBI Databases