Abstract
Background
Cesarean scar pregnancy (CSP) is a special form of ectopic pregnancy that lacks specific clinical manifestations. Artificially induced abortion may lead to severe complications such as massive bleeding and even uterine rupture, posing a threat to the safety of pregnant women. Magnetic resonance imaging (MRI) has potential advantages in evaluating CSP. This study aimed to analyze the value of MRI with different combinations of sequences in diagnosing CSP following a cesarean section and to evaluate the clinical value of MRI in classifying CSP.
Methods
We conducted a retrospective analysis on the clinical and imaging data of 80 patients with suspected CSP on ultrasound examination. The MRI data of all patients were divided into four combinations: combination A, T1-weighted imaging (T1WI) + T2-weighted imaging (T2WI); combination B, T1WI + T2WI + diffusion-weighted imaging (DWI); combination C, T1WI + T2WI + dynamic contrast-enhanced (DCE) MRI; and combination D, T2WI + DWI + DCE-MRI. The differences between these MRI sequence combinations were compared. Imaging features were observed, recorded, and used for MRI classification. Differences in imaging features between MRI classifications were also compared to determine their clinical significance.
Results
Of the 80 cases confirmed by postoperative pathology, 67 (83.75%) were CSP. The area under the curve for the combinations C and D was larger (0.966 and 0.979, respectively) than that for combination A (0.883). The sensitivity, specificity, positive predictive value, and negative predictive value for combinations C and D were higher (combination C: sensitivity 98.51%, specificity 92.31%, positive predictive value 98.53%, and negative predictive value 92.31%; combination D: sensitivity 95.52%, specificity 92.31%, positive predictive value 98.46%, and negative predictive value 80.00%). The distribution of CSP type I (filled type), type II (partially filled type), and type III (covered type) was 19.40%, 59.70%, and 20.90%, respectively. There was no statistically significant difference in the length of the contact surface between the gestational sac and the scar among the MRI-type groups (H =0.012; P=0.994). However, the minimum thickness of the scar at the implantation site of type I was less than that in type II (H =−16.192; P=0.028), and the area of the gestational sac in the sagittal position was smaller in type I than in type III (H =−24.467; P=0.003).
Conclusions
The preferred MRI sequence combination for diagnosing CSP should be T2WI + DWI + DCE-MRI. MRI can effectively visualize the relationship between the gestational sac and the incisional diverticulum in CSP and facilitate imaging-based staging.
Keywords: Scar pregnancy, magnetic resonance imaging (MRI), sequence combinations
Introduction
Cesarean scar pregnancy (CSP) is the implantation of a gestational sac within the scar of a previous uterine incision following a cesarean section and is considered to be a special form of ectopic pregnancy (1-3). Misdiagnosis and inappropriate management, such as an artificially induced abortion, can lead to severe complications such as heavy bleeding or even uterine rupture, posing significant risks to the life of pregnant women (4). The diagnosis of CSP primarily relies on ultrasound examination, which can include factors such as the patient’s body habitus, vaginal bleeding, and the examiner’s skill level, resulting in a diagnostic consistency rate below 90% (1,4). Furthermore, some patients refuse transvaginal ultrasound, and transabdominal ultrasound requires the patient to properly fill the bladder, while the probe compression procedure may exacerbate vaginal bleeding and risk uterine rupture. Three-dimensional color Doppler ultrasound (3D-US) is an effective supplement to two-dimensional examination, but it is still limited in showing the adjacent uterine tissue and the myometrium are invaded. Moreover, the diagnostic accuracy of ultrasound relies heavily on the operating skill of the examining physician. Meanwhile, contrast-enhanced ultrasound (CEUS) is time-consuming and relatively costly, and it is unclear whether the microbubbles created when the contrast agent is injected can cross the placenta and affect the fetus.
Magnetic resonance imaging (MRI) offers distinct advantages in the evaluation of CSP as it can better illustrate the implantation site, size, and the relationship between the gestational sac and the scar. Dynamic contrast-enhanced MRI (DCE-MRI) can clarify the internal structure of the gestational sac and the depth of myometrial infiltration, which is helpful for evaluating the risk of bleeding and providing valuable clinical treatment references. The choice of clinical treatment is chiefly informed by the CSP type, with type I (filled type) typically being treated via drug therapy and curettage. For type II (partially filled type), the local and surrounding blood flow of the lesion are considered in determining the treatment: if the blood supply is not rich, drug therapy and curettage are preferred; if the lesion has abundant blood supply, uterine artery embolization should be performed before surgery and curettage should be performed within 48 hours. Type III (covered type) CSP involves preoperative uterine artery embolization followed by uterine repair or adhesiolysis. Studies on enhanced MRI for CSP diagnosis and treatment are limited, with most research focusing on the MRI characteristics of CSP (5,6); however, few studies have examined the diagnostic value of different sequence combinations for CSP. Therefore, we conducted this study to assess the potential of different MRI sequence combinations to diagnosis CSP and to establish MRI-based classifications of CSP in order to support personalized clinical treatment plans. We present this article in accordance with the STARD reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2589/rc).
Methods
Patient information
We retrospectively analyzed the clinical and imaging data of 80 patients suspected of CSP via ultrasound examination at Sichuan Tianfu New Area People’s Hospital from January 2020 to May 2023. All patients underwent 1.5-T MRI with a MAGNETOM Avanto device (Siemens Healthineers, Erlangen, Germany) with multiple sequences. Patients were aged 24–45 years (mean age 32.96±4.29 years) and had a history of 1–3 cesarean sections, with the shortest interval from the last cesarean section being less than 1 year and the longest being 16 years. Patients presented with 27–72 days of amenorrhea, vaginal bleeding (46 cases), morning sickness (33 cases), and abdominal pain (21 cases), along with elevated serum human chorionic gonadotropin (HCG) levels. The patient inclusion criteria were as follows: (I) suspicion of CSP based on ultrasound examination; (II) less than 12 weeks of amenorrhea; and (III) complete clinical, pathological, and MRI data. Meanwhile, the exclusion criteria were as follows: (I) metal implants in the body; (II) claustrophobia; (III) uterine fibroids, uterine adenomyosis, ovarian lesions, etc.; (IV) critical conditions; and (V) treatment or artificial abortion before the examination.
Instruments and methods
Calmly breathing patients in the supine position underwent pelvic scans, covering the iliac crest to the pubic symphysis. The scanning sequence was as follows: axial fast spin echo T1-weighted imaging (T1WI) [repetition time (TR) =670 ms, echo time (TE) =12 ms, matrix =320×320, field of view (FOV) =260×260 mm2, slice thickness =3 mm, and slice spacing =1 mm], axial fast spin echo T2-weighted imaging (T2WI) with fat suppression (TR =4,410 ms, TE =72 ms, matrix =256×320, FOV =260×260 mm2, slice thickness =3 mm, and slice spacing =1 mm), sagittal T2WI (TR =3,640 ms and TE =86 ms), coronal T2WI (TR =4,200 ms and TE =78 ms), and diffusion-weighted imaging (DWI) (TR =4,500 ms, TE =86 ms, and b =50 and 1,000 s/mm2). For DCE-MRI scanning, gadoteric acid meglumine was injected into the cubital vein at a concentration of 0.1 mmol/kg and a rate of 3.0 mL/s. Enhanced scanning was performed 30 s after injection. The parameters of DCE-MRI were as follows: TR =4.7 ms, TE =1.7 ms, matrix =192×192, and slice thickness =3 mm. This retrospective study was approved by Medical Ethics Committee of Sichuan Tianfu New Area People’s Hospital (approval No. 2021012) and was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The requirement for written informed consent was waived by the Medical Ethics Committee due to the retrospective design of the study. None of the patients experienced any allergic reactions to contrast agents during the examination process.
Image analysis and typing
The MR images of all patients were divided into four combinations: combination A, T1WI + T2WI; combination B, T1WI + T2WI + DWI; combination C, T1WI + T2WI + DCE-MRI; and combination D, T2WI + DWI + DCE-MRI. Two radiologists (C.R.W., X.L.Y., with 7 and 18 years of experience in reading rectal MRI, respectively) evaluated the images using double-blind and physician diagnostic confidence scoring methods, with any discrepancies being resolved via discussion. When the two radiologists had different opinions, a third radiologist was conducted. Diagnostic confidence was scored on a scale from 1 to 5 (7) as follows: 1 point, not CSP; 2 points, less likely to be CSP; 3 points, possibly CSP; 4 points, more likely to be CSP; and 5 points, definitely CSP. The following data were recorded: gestational sac signal (cystic or cystic-solid), minimum scar thickness at the implantation site (mm), contact surface length between the gestational sac and scar (mm), and sagittal gestational sac area (maximum length × maximum width). MRI features were categorized into the three types following types based on the relationship between the gestational sac and the incisional diverticulum (8,9): (I) type I—the incisional diverticulum is clear, the gestational sac is completely embedded in it, and the diverticular cavity disappears; (II) type II—the incisional diverticulum is clear, the gestational sac is partially filled in, and the diverticular cavity is partially visible; and (III) type III—the incisional diverticulum is not visible, and the corresponding area is occupied by the gestational sac. The technical route is shown in Figure 1.
Figure 1.
Flowchart of patient inclusion. Combination A: T1WI + T2WI. Combination B: T1WI + T2WI + DWI. Combination C: T1WI + T2WI + DCE-MRI. Combination D: T2WI + DWI + DCE-MRI. CSP, cesarean scar pregnancy; DCE, dynamic contrast-enhanced; DWI, diffusion-weighted imaging; MRI, magnetic resonance imaging; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging; type I, filled type; type II, partially filled type; type III, covered type.
Statistical analysis
SPSS 25 software (IBM Corp., Armonk, NY, USA) was used for statistical analysis. Normally distributed data are expressed as the mean ± standard deviation, while nonnormally distributed data are expressed as the median (interquartile range). Meanwhile, count data are expressed as the frequency (n) and proportion (%). The Mann-Whitney test was used to compare the differences between MRI sequence combinations. Receiver operating characteristic (ROC) curve analysis was applied to determine significant differences. The area under the curve (AUC) was used to assess diagnostic efficacy, with the optimal cutoff values being determined via the maximum Youden index. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated. The Kruskal-Wallis test was used to compare the minimum scar thickness, contact surface length, and sagittal gestational sac area between the four MRI combinations, with significant differences further analyzed via Bonferroni correction. A P value <0.05 indicated statistical significance.
Results
Diagnostic confidence scores
Of the 80 cases, 67 (83.75%) were confirmed to have CSP by postoperative pathology. The diagnostic confidence scores for CSP of the four different MRI sequence combinations are shown in Table 1. The Mann-Whitney test results indicated that there were statistically significant differences (P<0.05) in the diagnostic confidence scores of CSP between the four combinations of MRI sequences.
Table 1. Comparison of CSP diagnostic confidence scores between the four different MRI sequence combinations.
| Inspection plan | CSP (n=67) | Non-CSP (n=13) | Z value | P value |
|---|---|---|---|---|
| T1WI + T2WI | 3.00 (0.00) | 2.00 (1.00) | −4.816 | <0.001 |
| T1WI + T2WI + DWI | 3.00 (1.00) | 2.00 (1.00) | −5.653 | <0.001 |
| T1WI + T2WI + DCE | 4.00 (1.00) | 2.00 (1.00) | −5.591 | <0.001 |
| T2WI + DWI + DCE | 5.00 (1.00) | 1.00 (1.00) | −5.950 | <0.001 |
The data in each group did not obey the normal distribution and are expressed as the median (interquartile range). CSP, cesarean scar pregnancy; DCE, dynamic contrast-enhanced; DWI, diffusion-weighted imaging; MRI, magnetic resonance imaging; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging.
Diagnostic efficacy
The diagnostic efficacy of different MRI sequence combinations for diagnosing CSP based on the physician’s diagnostic confidence score is shown in Table 2. ROC curve (Figure 2) analysis indicated that combinations C (T1WI + T2WI + DCE-MRI) and D (T2WI + DWI + DCE-MRI) had higher AUC values (0.966 and 0.979, respectively) compared to combination A (T1WI + T2WI), which had an AUC of 0.883. The sensitivities, specificities, positive predictive values, and negative predictive values for combinations C and D were also higher.
Table 2. The diagnostic efficacy of different MRI sequence combinations for CSP based on physician diagnostic confidence scores.
| Inspection plan | Threshold | Sensitivity (%) | Specificity (%) | Positive predictive value (%) | Negative predictive value (%) | AUC (95% CI) |
|---|---|---|---|---|---|---|
| T1WI + T2WI | 2.50 | 85.07 | 84.62 | 96.61 | 52.38 | 0.883 (0.781–0.984) |
| T1WI + T2WI + DWI | 2.50 | 95.52 | 92.31 | 98.46 | 80.00 | 0.962 (0.908–1.000) |
| T1WI + T2WI + DCE | 2.50 | 98.51 | 92.31 | 98.53 | 92.31 | 0.966 (0.905–1.000) |
| T2WI + DWI + DCE | 3.50 | 95.52 | 92.31 | 98.46 | 80.00 | 0.979 (0.943–1.000) |
AUC, area under the curve; CI, confidence interval; CSP, cesarean scar pregnancy; DCE, dynamic contrast-enhanced; DWI, diffusion-weighted imaging; MRI, magnetic resonance imaging; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging.
Figure 2.
ROC curves for the comparison of diagnostic efficacy of the different MRI sequence combinations. Combination A: T1WI + T2WI. Combination B: T1WI + T2WI + DWI. Combination C: T1WI + T2WI + DCE-MRI. Combination D: T2WI + DWI + DCE-MRI. DCE, dynamic contrast-enhanced; DWI, diffusion-weighted imaging; MRI, magnetic resonance imaging; ROC, receiver operating characteristic; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging.
Comparison of imaging features
Among the 67 patients with CSP, the gestational sac was predominantly cystic (82.09%). The distribution of CSP types was as follows: type I, 19.40%; type II, 59.70%; and type III, 20.90%. A comparison of the imaging features of the different MRI classifications are shown in Table 3. The MRI classification groups did not differ significantly in terms of length of the contact surface between the gestational sac and the scar (P>0.05). However, there were statistically significant differences in the minimum thickness of the scar at the implantation site of the gestational sac and the sagittal area of the gestational sac between the groups (P<0.05). The results of pairwise comparisons between the groups are shown in Table 4. The minimum thickness of the scar at the implantation site of the gestational sac of type I (Figure 3) was smaller than that of type II (Figure 4) (P<0.05), and the sagittal area of the gestational sac of type I was smaller than that of type III (Figure 5) (P<0.05).
Table 3. Comparison of imaging features of the different MRI classifications.
| Image feature | Type I (n=13) | Type II (n=40) | Type III (n=14) | H value | P value |
|---|---|---|---|---|---|
| Minimum scar thickness at the implantation site (mm) | 1.96±0.24 | 2.69 (1.62) | 2.81±0.48 | 6.966 | 0.031 |
| Length of the contact surface between the gestational sac and the scar (mm) | 26.13±3.51 | 23.52 (18.99) | 28.43±4.43 | 0.012 | 0.994 |
| Sagittal gestational sac area (mm2) | 349.99 (660.41) | 818.82 (762.22) | 1,268.53±213.61 | 10.715 | 0.005 |
The minimum scar thickness at the implantation site of the type II gestational sac, the length of the contact surface between the gestational sac and the scar, and the sagittal gestational sac area of type I and type II did not follow a normal distribution and are expressed as the median (interquartile range). The remaining data followed a normal distribution and are expressed as the mean ± standard deviation. MRI, magnetic resonance imaging; type I, filled type; type II, partially filled type; type III, covered type.
Table 4. Pairwise comparison of the imaging features between the different MRI classifications.
| Imaging features | Type I–type II | Type I–type III | Type II–type III | |||||
|---|---|---|---|---|---|---|---|---|
| H value | P value | H value | P value | H value | P value | |||
| Minimum scar thickness at the implantation site | −16.192 | 0.028 | −9.692 | 0.589 | 6.500 | 0.848 | ||
| Sagittal gestational sac area | −14.113 | 0.070 | −24.467 | 0.003 | −10.354 | 0.261 | ||
MRI, magnetic resonance imaging; type I, filled type; type II, partially filled type; type III, covered type.
Figure 3.
A 36-year-old female with type I CSP. The scores for Combinations A, B, C, and D were 3, 4, 5, and 5 points, respectively. The patient only underwent curettage surgery. (A) The T1WI transverse axial position showed that the myometrium of the anterior and lower wall of the uterus was thin; a cystic long T1 signal shadow (red arrow) was visible, and the cyst wall was isointense. (B) DWI showed that the cyst wall (red arrow) had a slightly high signal. (C) The T2WI sagittal position showed that the cyst wall had a slightly high signal, the gestational sac was clearly demarcated from the uterine wall, the incision diverticulum was clear, and the gestational sac (red arrow) was completely embedded in it. (D,E) On enhanced scanning, the cyst wall (red arrows) was significantly enhanced, while the cyst cavity was not significantly enhanced. Combination A: T1WI + T2WI. Combination B: T1WI + T2WI + DWI. Combination C: T1WI + T2WI + DCE-MRI. Combination D: T2WI + DWI + DCE-MRI. CSP, cesarean scar pregnancy; DCE, dynamic contrast-enhanced; DWI, diffusion-weighted imaging; MRI, magnetic resonance imaging; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging; type I, filled type.
Figure 4.
A 26-year-old female with type II CSP. The patient only underwent curettage surgery. (A) The T1WI sagittal view showed scar shadow (red arrow) in the anterior lower segment of the uterus. (B) The T2WI sagittal view showed a clear scar incision of the diverticulum and partial filling of the gestational sac, with the diverticulum (red arrow) being partially visible. (C) In enhanced imaging in the sagittal view, the gestational sac wall (red arrow) was significantly enhanced, while the inner wall was smooth. CSP, cesarean scar pregnancy; T1WI, T1-weighted imaging; T2WI, T2-weighted imaging; type II, partially filled type.
Figure 5.
A 37-year-old female with type III CSP (mass type). The patient underwent curettage and adhesiolysis of the uterine cavity. (A) The T2WI of the sagittal plane showed a mass shadow (red arrow) with mixed high and low signals in the anterior lower segment of the uterus, with no clear cystic diverticulum shadow. (B) Enhanced imaging of the sagittal plane showed obvious strip-like and nodular enhancement in the mass (red arrow), with an unclear boundary with the uterine wall and uneven enhancement of the adjacent uterine wall. CSP, cesarean scar pregnancy; T2WI, T2-weighted imaging; type III, covered type.
Discussion
In recent years, with the relaxation of the three-child policy in China, the cesarean section rate has increased significantly, as has the incidence of CSP. The pathogenesis of CSP remains unclear, but the potential mechanisms include a hypoxic environment conducive to trophoblast proliferation, poor healing of the uterine scar providing conditions for fertilized egg implantation, rapid migration or delayed development of the gestational sac, and single-layer continuous suturing leading to uterine incision diverticula and wide scars (10-13).
MRI, with its superior soft tissue resolution, can clearly show the relationship between the gestational sac and the scar. Enhanced MRI can visualize the integrity of the gestational sac, the site of implantation, and the depth of myometrial infiltration, aiding in clinical assessment and treatment planning (14).
In our study, the AUC of combination A was 0.883, with both the sensitivity and specificity exceeding 80%, demonstrating a certain degree of diagnostic efficacy. Generally, the T2WI sequence is effective in displaying the high-signal intensity of the gestational sac, the low-signal fibrous scar, and the thin uterine myometrial structure (15), while the T1WI sequence involves high signal intensity in cases of pregnancy with bleeding, thus serving as a diagnostic prompt (16). DCE-MRI can indirectly reflect the blood supply of CSP and facilitate the identification of trophoblastic tumors. Additionally, DCE-MRI prominently enhances the appearance of villi and early placental structures, making it more suitable for assessing the relationship between the gestational sac’s implantation site and the scar diverticulum (17). This allows for further evaluation of villous adhesion, implantation, or perforation, providing a critical basis for the early clinical prediction of CSP risk and the formulation of personalized treatment plans (18). Consequently, the sensitivity, specificity, positive predictive value, and negative predictive value of combinations C and D in this study were significantly higher than those of combinations A and B, corroborating the findings of previous research (7). The gestational sac in CSP is predominantly cystic, and the normal villous structure appears as a high signal on the DWI sequence, while the myometrium shows an isosignal. Observing high-signal areas similar to that of the villous structure in the myometrium on DWI allows for further evaluation of villous implantation in CSP (18,19). In our study, the diagnostic efficacy of combination B was superior to that of combination A. Therefore, for patients who are allergic to gadolinium contrast agents or have renal insufficiency and are unsuitable for MRI enhancement examination, T1WI + T2WI + DWI can serve as an alternative sequence combination. However, it is important to note that for patients without contraindications to MRI enhancement examination, T2WI + DWI + DCE remains the preferred sequence combination, as it can provide more accurate diagnostic value.
MRI can help the clinicians correctly diagnose CSP, allow for the visualization of gestational sacs of varying shapes, and facilitate MRI-based classification. In some cases of CSP, the lower uterine myometrium is either thin or absent and may be accompanied by villous erosion. Furthermore, the presence of surgical scars can impair the uterus’s ability to contract efficiently, leading to a heightened risk of severe bleeding. One study indicated that the failure rate of type III CSP during artificial abortion is high (7). If an artificial abortion is performed without a clear preoperative diagnosis, it can result in uterine rupture and significant bleeding, underscoring the need for careful evaluation. Effective preoperative assessment of the relationship between the gestational sac and the scar diverticulum, along with MRI classification, provides a valuable basis for clinical decision-making.
The minimum scar thickness at the implantation site of the gestational sac is an independent risk factor for major bleeding during CSP surgery, with an optimal threshold of 2.25 mm, and it has been reported that it has the best diagnostic efficacy in predicting bleeding risk (11). When the minimum scar thickness at the implantation site of the gestational sac becomes thinner, the risk of major bleeding during CSP surgery increases. Our study revealed that the minimum scar thickness at the implantation site of a type I gestational sac was significantly smaller than that of type II (P<0.05), and the sagittal gestational sac area was smaller in type I than in type III (P<0.05). This finding can be attributed to the clarity of the scar diverticula in type I CSP, which allows for the gestational sac to be completely embedded, causing the diverticular cavity to disappear. In early pregnancy, the rich surrounding blood supply supports embryonic growth; however, as the pregnancy progresses, the increased nutritional demands and insufficient adhesion of the gestational sac lead to vaginal bleeding, prompting early clinical intervention. This results in the gestational sac being the smallest at the time of detection, aligning with the other findings (8).
Type III CSP primarily consists of a mass-type gestational sac, with the corresponding area of the scar diverticula being occupied by the gestational sac, surrounded by the uterine wall. The embryo receives ample blood supply and nutrition, allowing it to grow larger. The likelihood of vaginal bleeding is relatively low, and the condition may only be clinically detected at a later gestational age (20,21). Some type III CSP cases may involve implantation into the myometrium. Enhanced MRI can distinctly show villous tissue infiltrating and growing into the myometrium, further confirming that the combination of T2WI, DWI, and DCE sequences is optimal for CSP examination. A few studies have shown that MRI is superior to ultrasound in the diagnosis of type III CSP, especially for the mass type. MR images can clearly show the degree and extent of lesion enhancement within the mass and the blood supply of the pregnancy sac, which indirectly reflects the villi activity, thus affecting the choice of surgical methods (18,20). In addition, we found that there was no statistically significant difference in the length of the contact surface between the gestational sac and the scar between the different MRI types (P>0.05). However, further research with a larger sample size is needed to verify these findings.
This study involved several limitations which should be addressed. First, the sample size was relatively small, and there were disparities in the number of cases between groups; moreover, given the retrospective design, an expanded sample size in future research is needed to enhance result accuracy. Second, we did not examine the differences between various MRI classifications in terms of clinical surgical procedure selection or intraoperative bleeding risk. Third, no comparative analysis was conducted with traditional ultrasound classifications, which should be completed in subsequent investigations.
Conclusions
MRI is an effective diagnostic tool for CSP, offering superior visualization and classification capabilities. The preferred sequence combination for CSP diagnosis is T2WI + DWI + DCE-MRI. MRI classification can guide clinical treatment decisions, helping to improve patient prognosis. Routine MRI examination is recommended for patients with suspected CSP on ultrasound to minimize diagnostic errors and treatment risks. In future research, the sample size should be expanded and the clinical implications of MRI classifications explored in greater depth. In addition, we plan to conduct prospective research in collaboration with multiple centers in future studies and examine the potential advancements in MRI technology and machine learning for automated CSP diagnosis.
Supplementary
The article’s supplementary files as
Acknowledgments
We are grateful for the financial support from the Sichuan Medical Association, who provided critical technical assistance in data collection and laboratory resources. The funding body had no role in study design, data interpretation, or manuscript preparation.
Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. This retrospective study was approved by the Medical Ethics Committee of Sichuan Tianfu New Area People’s Hospital (No. 2021012) and was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The requirement for written informed consent was waived by the Medical Ethics Committee due to the retrospective design of the study.
Footnotes
Reporting Checklist: The authors have completed the STARD reporting checklist. Available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2589/rc
Funding: This study was funded by the Sichuan Medical Association (Hengrui) Special Research Fund (No. 2021HR57).
Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2589/coif). M.N.C. worked in collaboration with Siemens Healthineers, Chengdu, China, in MR research. The other authors have no conflicts of interest to declare.
Data Sharing Statement
Available at https://qims.amegroups.com/article/view/10.21037/qims-2024-2589/dss
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