Abstract
Background
Motion artifacts caused by respiration, cardiac pulsation, and vascular flow often degrade image quality in conventional contrast-enhanced transverse T1-weighted magnetic resonance imaging (MRI) of the thoracic spine, hindering lesion detection and characterization. Although radial k-space sampling sequences have demonstrated strong motion artifact suppression through non-Cartesian acquisition trajectories, their clinical value in contrast-enhanced thoracic spine MRI remains unverified. This study aimed to evaluate the clinical utility of the free-breathing radial k-space sampling sequence for contrast-enhanced transverse T1-weighted MRI of thoracic spine.
Methods
Total of 48 patients with thoracic vertebral lesions enrolled in this prospectively study underwent contrast-enhanced thoracic spine examination on a 3T MRI scanner from July 2024 to March 2025. After contrast administration, three transverse sequences, including conventional two-dimensional T1-weighted imaging with modified Dixon turbo spin echo (2D T1WI-mDixon-TSE), breath-hold three-dimensional T1-weighted imaging with modified Dixon gradient echo (3D T1WI-mDixon-GRE), and free-breathing 3D volumetric accelerated navigator echo with extended dynamic range (3D VANE XD) were acquired. Signal-to-noise ratio (SNR) was measured at the central slice. Two radiologists independently scored artifact suppression, thoracic vertebra/lesion clarity and overall image quality using a 4-point Likert scale. The differences in SNR and subjective evaluation scores among above three sequences were compared and analyzed.
Results
The free-breathing 3D VANE XD and 3D T1WI-mDixon-GRE sequences achieved significantly higher SNR than 2D T1WI-mDixon-TSE sequence (both p < 0.01). In the subjective evaluation of artifact suppression, the free-breathing 3D VANE XD sequence also scored highest [3.90(3.81, 3.95)], followed by the breath-hold 3D T1WI-mDixon-GRE [3.55(3.50, 3.70)] and 2D T1WI-mDixon-TSE sequences [2.90(2.75, 3.08)]. For the clarity of thoracic vertebra and lesion, the free-breathing 3D VANE XD sequence scored significantly highest (both p < 0.01). And the overall image quality of free-breathing 3D VANE XD sequence was significantly best [3.90 (3.85, 3.95)] than the other two sequences (both p < 0.01).
Conclusion
The free-breathing 3D VANE XD sequence significantly improved the image quality of contrast-enhanced transverse T1-weighted MRI for thoracic spine, supporting its integration into routine clinical practice.
Keywords: Radial k-space sampling, Signal-to-noise ratio, Artifact suppression, Thoracic spine MRI
Background
In clinical practice, precise evaluation of thoracic spinal lesions, including tumors, nerve injuries and vertebral infectious is critical for diagnosis and treatment in patient management. With the inherent advantages of multiparametric, multiplanar imaging, and absence of ionizing radiation, MRI has established itself as the first-line diagnostic tool for this patient population [1–3]. Contrast-enhanced thoracic spine MRI usually necessitates multiplanar acquisitions to fully characterize lesion enhancement patterns, delineate spatial extent, and define anatomical relationships with surrounding structures. Among these, T1-weighted transverse imaging serves as the key acquisition plane of the thoracic spine MRI protocol, providing indispensable diagnostic information for lesion characterization. However, the proximity of the thoracic spine to thoracopulmonary and cardiopulmonary vasculature renders it particularly susceptible to motion artifacts induced by respiratory, cardiac pulsations, and vascular flow [4]. These artifacts inevitably degrade image quality and hindering lesion detection and characterization, which is still a challenge in contrast-enhanced thoracic spine MRI. Recent advancements in radial k-space sampling-based pulse sequences (e.g., free-breathing 3D VANE XD) have demonstrated robust motion artifact suppression through non-Cartesian data acquisition trajectories [5]. Although existing studies validate the superiority of radial sampling in dynamic organ imaging, including cardiac [6, 7], thoracic [8], hepatic [9–12], angiography [13, 14], and particularly pediatric abdominal applications [15–17], its clinical value in contrast-enhanced thoracic spine MRI remains unverified. This prospective controlled study systematically evaluates conventional Cartesian k-space sampling against free-breathing radial k-space sampling for contrast-enhanced transverse T1-weighted MRI for thoracic spine by employing quantitative metrics and multi-dimensional subjective assessments, so as to provide basis for optimizing imaging protocol of contrast-enhanced thoracic spine MRI.
Materials and methods
Study population
This prospective study received institutional review board approval (No. B2023-007), and written informed consent was obtained from all participants. A total of 56 consecutive patients with suspected thoracic vertebral lesions who underwent 3.0T contrast - enhanced MRI at our institution from July 2024 to March 2025 were enrolled. The inclusion criteria were as follows: (1) patients who were highly suspected of thoracic vertebral lesions based on clinical comprehensive judgment by clinical physicians, (2) absence of MRI contraindications (non-compatible implants, severe claustrophobia, glomerular filtration rate < 30 mL/min/1.73 m²), (3) no prior related treatment before the MRI examination. While the exclusion criteria were as follows: (1) negative MRI findings, (2) images were unmeasurable due to severe artifacts caused by body movement during the examination. Three patients were excluded due to severe motion artifacts caused by intolerable pain, and five patients were excluded due to the absence of significant positive findings on MRI. Therefore, total of 48 subjects were ultimately included in the study (Fig. 1).
Fig. 1.
Inclusion and exclusion flowchart for healthy subjects and patients
Data acquisition
All examinations were performed on a Philips Ingenia CX 3.0T MRI system (Philips Healthcare, Best, the Netherlands) using a 24-channel head-neck coil combined with dStream table-embedded posterior coil. Conventional contrast-enhanced (CE) thoracic spine MRI protocol contained non-contrast-enhanced (NCE) and contrast-enhanced sequences.
Before contrast administration, sagittal T2-weighted imaging with modified Dixon turbo spin echo (T2WI-mDixon-TSE), sagittal T1WI-mDixon-TSE, sagittal zoom diffusion-weighted imaging (zoom-DWI) and transverse turbo spin-echo T2-weighted imaging (T2WI-TSE) sequences were scanned. After contrast administration, multiplanar T1WI-mDixon-TSE (sagittal/coronal/transverse) with additional other two transverse contrast-enhanced sequences, including breath-hold 3D T1WI-mDixon-GRE and free-breathing 3D VANE XD, were acquired. Notably, for the 3D VANE XD sequence, the in-plane acquisition mode used radial pseudo-golden-angle filling (radial percentage was 220%), and inter-slice acquisition mode used cartesian sequential filling. Contrast-enhanced scanning utilized Gadobutrol (Gadavist, Bayer AG) administered by hand-injected intravenous bolus at 0.1 mL/kg body weight, followed by a standardized 20 mL 0.9% sodium chloride flush. The specific parameters of the sequences were shown in Table 1.
Table 1.
Scanning parameters of thoracic spine MRI
| Sequences | T2WI- mDixon-TSE |
Zoom-DWI -b600 |
T2WI-TSE | 2D T1WI-mDixon-TSE | 3D T1WI-mDixon-GRE | 3D VANE XD | ||
|---|---|---|---|---|---|---|---|---|
| Orientation | sagittal | sagittal | transverse | sagittal | coronal | transverse | transverse | transverse |
| Contrast or not | NCE | NCE | NCE | NCE & CE | CE | CE | CE | CE |
| Fast imaging mode | TSE | EPI | TSE | TSE | TSE | TSE | TFE | TFE |
| Acquisition mode | Cartesian | Cartesian | Cartesian | Cartesian | Cartesian | Cartesian | Cartesian | Radial |
| FOV (mm×mm) | 190 × 340 | 280 × 120 | 180 × 200 | 190 × 340 | 120 335 | 200 × 200 | 320 × 300 | 250 × 250 |
| Thickness/gap (mm) | 3.5/0.35 | 3.5/0.35 | 4.0/0.4 | 3.5/0.35 | 4 1 | 4.0/0.4 | 4.0/-2.0 | 4.0/-2.0 |
| Matrix | 224 × 261 | 92 × 33 | 300 × 248 | 190 × 221 | 132 283 | 256 × 156 | 228 × 200 | 252 × 252 |
| PE | FH | AP | LR | FH | FH | LR / AP | AP | AP |
| TR(ms) | 2109 | 3000 | 2552 | 518 | 521 | 539 | 3.1 | 5.2 |
| TE(ms) | 100 | 78 | 100 | 20 | 7.04 | 6.4 | 1.1 | 1.5 |
| FA | 90° | 90° | 90° | 90° | 90° | 90° | 10° | 10° |
| Sense (RL & FH) | Off & 1.5 | off | 1.7 & off | Off &1.0 | Off & 1.0 | 2.0 & off | 1.0 & 1.0 | 1.0 & 1.6 |
| NSA | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 1 |
| Slices | 13 | 13 | 24 | 13 | 12 | 24 | 100 | 70 |
| Time duration (s) | 164 | 144 | 112 | 160 | 107 | 168 | 14 | 91 |
Note: NCE, non-contrast-enhanced; CE, contrast-enhanced; NSA, number of signal averages; PE, phase encoding
Image quality assessment
Objective assessment
Due to significant artifacts that frequently disrupt the visualization of vertebral bodies and lesions in the 2D T1WI-mDixon-TSE sequence, accurate measurement of the contrast-to-noise ratio is considerably challenging. To address this, the SNR of the paraspinal muscles at the central slice of the scan was employed as the primary quantitative metric for objective comparison in this study. Two radiologists, each with over five years of experience in MRI diagnosis, delineated a region of interest (ROI) of 200 mm² in the left paraspinal muscles at the central slice and measured the signal intensity (SI), denoted as SImuscle. On the same slice, three ROIs of 200 mm² each were delineated in the air 10 mm below the back skin. The standard deviation (SD) of these ROIs was measured, and the average of the three SD values was taken as the background noise, denoted as SDbg. The SNR for each sequence was calculated as the average of the two observers’ measurements, using the formula: SNR = SImuscle / SDbg.
Subjective evaluation
Two board-certified radiologists, each with more than five years of specialized experience in musculoskeletal MRI, independently reviewed all sequences for each patient. To minimize potential order bias, the presentation of image sequences was fully randomized during the review process. The image quality assessment was performed under a double-blind protocol in which both reviewers were blinded to the sequence names and patient identities. A validated 4 - point Likert scale was used to assess image quality mainly covered three key domains: image artifact, clarity of vertebral bodies and lesions, and overall image quality. The specific scoring criteria are as follows: 4 points = excellent (almost no artifact, clear display of vertebral bodies and lesions, easy for diagnosis), 3 points = good (few artifact, relatively clear display of vertebral bodies and lesions, diagnosable), 2 points = fair (artifacts present, insufficient clarity of vertebral bodies and lesions, marginally usable for diagnosis); 1 point = poor (obvious artifact, very unclear display of vertebral bodies and lesions, not usable for diagnosis).
Statistics analysis
All analyses were performed using SPSS Statistics v29.0 software (IBM Corp., Armonk, NY). Firstly, the Kolmogorov-Smirnov test was used to assess the normality of the data. If the data were normally distributed, they were described using the mean ± standard deviation; otherwise, the median and interquartile range was used for description. Friedman test was employed to analyze differences among paired data, while post-hoc pairwise comparisons were conducted using Wilcoxon signed-rank tests, with p-values adjusted for multiple comparisons using the Bonferroni method. A two-sided p-value of less than 0.05 was considered statistically significant. This study compared the differences in SNR among different sequences and compared the subjective image quality scores of different sequences.
Results
Patient baseline information and interobserver reliability
Total of 48 subjects were ultimately included in the study, comprising 11 females and 37 males, with ages ranging from 35 to 82 years (mean age: 63.11 ± 11.79 years). The baseline information of the patients was shown in Table 2. The interobserver reliability for the SNR measurements and subjective image quality scores of each sequence was analyzed, and the intraclass correlation coefficients (ICCs) all exceeding 0.90 (Table 3).
Table 2.
The characteristics of patients
| Characteristics | Value | |
|---|---|---|
| Age (year) | 63.11 ± 11.79 (35 ~ 82) | |
| Male / Female (n) | 37/11 | |
| Lesion | Thoracic vertebral metastasis from lung cancer (n) | 24 |
| Thoracic vertebral metastasis from breast cancer (n) | 9 | |
| Thoracic vertebral metastasis from prostate cancer (n) | 5 | |
| Thoracic vertebral hemangioma (n) | 3 | |
| Thoracic vertebral inflammatory lesions (n) | 7 | |
Table 3.
Interobserver reliability analysis of image quality scores
| Sequence | ICC (95% CI) | ||||||
|---|---|---|---|---|---|---|---|
| SNR | Image artifact | Clarity of vertebral bodies and lesions | Overall image quality | ||||
| 2D T1WI-mDixon-TSE | 0.94 (0.88–0.97) | 0.95 (0.91–0.98) | 0.96 (0.93–0.98) | 0.98 (0.96–0.99) | |||
| 3D T1WI-mDixon-GRE | 0.97 (0.94–0.99) | 0.93 (0.87–0.96) | 0.98 (0.96–0.99) | 0.97 (0.94–0.98) | |||
| 3D VANE XD | 0.98 (0.97–0.99) | 0.94 (0.89–0.97) | 0.92 (0.85–0.96) | 0.96 (0.93–0.98) | |||
Note: ICC, intraclass correlation coefficient; CI, confidence interval
Comparison of SNR among three sequences
The normality test indicated that the SNR values of the free-breathing 3D VANE XD sequence were not normally distributed (p < 0.05), while those of the other two sequences were normally distributed (p > 0.05). Significant differences in SNR among the three MRI sequences were found by Friedman test (Table 4). Pairwise comparisons using Wilcoxon signed - rank test showed that the free-breathing 3D VANE XD sequence had a significantly higher SNR than both the breath-hold 3D T1WI-mDixon-GRE and 2D T1WI-mDixon-TSE sequences. Specifically, compared to the 2D T1WI-mDixon-TSE sequence, the SNR of the free-breathing 3D VANE XD sequence was 52.13% higher. Additionally, the SNR of the breath-hold 3D T1WI-mDixon-GRE sequence was also significantly higher than that of the 2D T1WI-mDixon-TSE sequence (Table 5; Fig. 2). To control for Type I error inflation due to multiple comparisons, a Bonferroni correction was applied. After Bonferroni adjustment, no statistically significant difference in SNR was found between the free-breathing 3D VANE XD and the breath-hold 3D T1WI-mDixon-GRE sequences (p = 0.111).
Table 4.
Overall comparison of SNR among the three sequences
| Sequence | SNR | χ² | Kendall’s W | P value |
|---|---|---|---|---|
|
2D T1WI-mDixon-TSE 3D T1WI-mDixon-GRE |
117.43 ± 26.76 172.59 ± 58.50 |
63.79 | 0.66 | < 0.001 |
| 3D VANE XD | 178.42 (141.80, 207.36) |
Table 5.
Pairwise comparison of SNR among the three sequences
| 2D T1WI-mDixon-TSE vs. 3D T1WI-mDixon-GRE |
2D T1WI-mDixon-TSE vs. 3D VANE XD |
3D T1WI-mDixon-GRE vs. 3D VANE XD | |
|---|---|---|---|
| Z value | -6.00 | -5.99 | -2.09 |
| p value | < 0.001 | < 0.001 | 0.036 |
| Bonferroni-corrected p value | < 0.001 | < 0.001 | 0.108 |
Note: Bonferroni adjustment for multiple comparisons (n = 3) was applied. Significance was determined at an adjusted p value < 0.05
Fig. 2.
Contrast-enhanced thoracic spine MRI in an adult patient (age: 55–60) with thoracic vertebral tuberculosis (clinical diagnosis confirmed by positive T-SPOT.TB and tuberculosis antibody tests). Sagittal T2WI image (A) demonstrated abnormal hyperintensity at the anterior margins of T2-T7 vertebral bodies, and (B) was the corresponding transverse slice at the level indicated by the light red reference line on (A). Marked enhancement of the affected vertebrae (red arrow) was shown on the sagittal contrast-enhanced T1WI image (C). Figure (D) to (F) were the transverse contrast-enhanced 2D T1WI-mDixon-TSE, breath-hold 3D T1WI-mDixon-GRE and free-breathing 3D VANE XD sequences, respectively. These images corresponded to the same slice as (B). Serious artifacts caused by the pulsation of the heart and aorta (D) hindered the lesion evaluation. There was fewer artifact on image (E) and (F). However, the lesion on image (E) (pink arrow) was a bit obscure, and the lesion clarity on image (F) (orange arrow) was high. The SNR values for image (D-F) were 108.24, 216.67, and 230.43, respectively. Image (F) demonstrated superior overall image quality compared to image (D) and (E)
Comparison of subjective scores about image quality
The Kolmogorov-Smirnov test revealed non-normal distributions for most subjective scoring parameters across the three MRI sequences (p < 0.05), except for overall image quality scores of both 3D T1WI-mDixon-GRE and 2D T1WI-mDixon-TSE sequences (p > 0.05).
In terms of artifact suppression, results showed that the free-breathing 3D VANE XD sequence had the highest scores (median score: 3.90), followed by the breath-hold 3D T1WI-mDixon-GRE sequence (median score: 3.55), while the 2D T1WI-mDixon-TSE sequence had the lowest scores (median score: 2.90). There were statistically significant differences in scores both overall and between each pair of sequences (Table 6; Fig. 3, all p < 0.001). For clarity of thoracic vertebrae and lesions, the free-breathing 3D VANE XD images also scored significantly higher than the other two (both p < 0.01). Moreover, the overall image quality score for the free-breathing 3D VANE XD sequence was significantly higher than the other two groups (both p < 0.01) (Figs. 4, 5 and 6).
Table 6.
Subjective scores about image quality across three MRI sequences
| Sequences | Artifact suppression | Clarity of thoracic vertebrae and lesions | Overall image quality |
|---|---|---|---|
| 2D T1WI-mDixon-TSE | 2.90 (2.75, 3.08) | 2.90 (2.65, 3.00) | 2.87 ± 0.22 |
| 3D T1WI-mDixon-GRE | 3.55 (3.50, 3.70) | 3.20 (3.10, 3.30) | 3.44 ± 0.19 |
| 3D VANE XD | 3.90 (3.81, 3.95) | 3.90 (3.86, 3.95) | 3.90 (3.85, 3.95) |
| χ² | 93.58 | 96.00 | 94.04 |
| p value | < 0.001 | < 0.001 | < 0.001 |
Fig. 3.
The bar chart of subjective scores about image quality across three MRI sequences (**: p < 0.001)
Fig. 4.
Contrast-enhanced thoracic spine MRI in an adult patient (age: 40–45) with T4 vertebral metastasis from lung cancer. Sagittal T2WI image (A) demonstrated flattening of the T4 vertebral. Transverse T2WI (B) at the level indicated by the light red reference line in (A) showed heterogeneous tumor infiltration with an occupying lesion anterior to the right side. Figure (C) to (E) were the transverse contrast-enhanced 2D T1WI-mDixon-TSE, breath-hold 3D T1WI-mDixon-GRE and free-breathing 3D VANE XD sequences, respectively. These images corresponded to the same slice as (B). Serious pulsation artifacts from cardiothoracic structures compromising tumor assessment. Fewer artifact on image (E) and (F) was found. However, the lesion on image (D) (pink arrow) was obscure, and image (E) (yellow arrow) provided optimal artifact suppression and clear tumor delineation. Subjective scores about artifact suppression were 2.95, 3.75, and 3.90 for Figs. (C-E), respectively; in terms of vertebral and lesion clarity, 3.0, 3.25, and 3.85. Fig. (E) showed superior overall image quality compared to Figs. (C) and (D)
Fig. 5.
Contrast-enhanced thoracic spine MRI in an adult patient (age: 50–55) with stable T7 vertebral hemangioma (confirmed by 6-month follow-up imaging and negative laboratory tests). Sagittal T2WI image (A) demonstrated an 8-mm hyperintense lesion (red arrow) at the T7 inferior endplate. Transverse T2WI image (B) showed the lesion’s maximal cross-section. Significant enhancement of the lesion (green arrow) was shown on the sagittal contrast-enhanced T1WI image (C). Figure (D) to (F) were the transverse contrast-enhanced 2D T1WI-mDixon-TSE, breath-hold 3D T1WI-mDixon-GRE and free-breathing 3D VANE XD sequences, respectively. These images corresponded to the same slice as (B). Serious artifacts caused by cardiothoracic pulsation (D) covered this tiny lesion. Reduced artifacts were found on image (E) and (F). However, it was hard to identify this small lesion on image (E) (pink arrow), and image (F) (orange arrow) clearly depicted the lesion. Subjective scores about artifact suppression were 2.50, 3.50, and 3.95 for image (D-F), respectively; in terms of vertebral and lesion clarity, 2.50, 3.15, and 3.95 respectively; in aspects of overall image quality, 2.5, 3.35, and 3.95 respectively
Fig. 6.
Contrast-enhanced thoracic spine MRI in an adult patient (age: 45-50) with T10 vertebral metastasis from breast cancer. Sagittal and transverse T2-weighted images (A-B) demonstrate slight flattening of the T10 vertebral body with heterogeneous signal intensity, containing a nodular lesion (approximately 22 × 18 mm) with lobulated margins (red arrow). Moderate enhancement of the lesion (green arrow) was shown on the sagittal contrast-enhanced T1WI image (C). Figure (D) to (F) were the transverse contrast-enhanced 2D T1WI-mDixon-TSE, breath-hold 3D T1WI-mDixon-GRE and free-breathing 3D VANE XD sequences, respectively. These images corresponded to the same slice as (B). Although artifacts were avoided from cardiothoracic pulsation on this section, motion artifacts from respiration made the lesion appear indistinct (yellow arrow, D). Reduced artifacts were found on image (E) and (F). The lesion was visible on image (E) (pink arrow), but its lobulated margins were much more clearly demonstrated on image (F) (orange arrow). Subjective scores about artifact suppression were 3.20, 3.80, and 3.95 for image (D-F), respectively; in terms of vertebral and lesion clarity, 3.20, 3.45, and 3.95 respectively; in aspects of overall image quality, 3.20, 3.55, and 3.95 respectively
Discussion
This investigation conducted a systematic comparative analysis of three axial T1-weighted contrast-enhanced acquisition protocols for thoracic spine MRI. The free-breathing 3D VANE XD and 3D T1WI-mDixon-GRE sequences achieved significantly higher SNR than 2D T1WI-mDixon-TSE sequence. Subjective evaluations demonstrated superior performance of the free-breathing 3D VANE XD sequence than the other two sequences in artifact suppression, clarity of vertebral bodies and lesions, and overall image quality statistically.
Most clinical sequences used Cartesian sampling, suitable for organs with minimal movement. It sampled via a regular grid with straight trajectories in k-space. However, movements (e.g., breathing, heartbeat or body involuntary movement) could alter the phases of signal in k-space, resulting in motion artifacts [4]. In this study, conventional 2D T1WI-mDixon-TSE sequences were significantly compromised by respiratory and cardiac motion artifacts, resulting in low subjective image scores (< 3). These scores barely met diagnostic requirements and potentially hindered clinical evaluation of vertebral lesions. The 3D T1WI-mDixon-GRE sequence, incorporating rapid imaging and breath-hold techniques, demonstrated better performance in artifact reduction. Compared to the 2D T1WI-mDixon-TSE, the 3D T1WI-mDixon-GRE sequence significantly improved image quality in terms of SNR, artifact suppression, lesion clarity, and overall quality. However, this sequence has notable limitations. First, the constrained breath-hold duration limits achievable resolution, potentially reducing sensitivity for small lesion detection. Second, even the relatively short 14-second breath-hold period might prove challenging for specific patient populations, including elderly individuals, pediatric patients, and those with cardiopulmonary comorbidities, thereby restricted its broader clinical applicability.
The free-breathing 3D VANE XD sequence combines radial in-plane filling with Cartesian inter-slice linear filling. Unlike conventional Cartesian sampling, radial sampling employs an asymmetric k-space trajectory, prioritizing central k-space data while sparsely acquiring peripheral regions. Such sampling characteristics not only preserve tissue contrast but also enable robust motion correction through continuous acquisition of central k-space phase information [18]. As a result, radial-based free-breathing 3D VANE XD sequence demonstrated inherent resilience to periodic physiological motions including respiratory and cardiac activity, leading to significant artifact reduction [19–21]. For optimal balance between image quality and scan efficiency in our study protocol, we implemented an inter-slice acceleration factor of 1.6, achieving an acquisition time of 91 s while maintaining diagnostic image quality across the required anatomical coverage. Quantitative analysis revealed that the free-breathing 3D VANE XD sequence achieved significantly higher SNR than the conventional Cartesian-based 2D T1WI-mDixon-TSE sequence, while no significant different was observed compared to the breath-hold Cartesian-based 3D T1WI-mDixon-GRE sequence, consistent with prior research [22, 23]. Subjective evaluations further demonstrated its superiority. Free-breathing 3D VANE XD sequence was scored highest in artifact suppression, vertebral/lesion delineation, and overall image quality, followed by the breath-hold 3D T1WI-mDixon-GRE sequence, while the 2D T1WI-mDixon-TSE sequence ranked lowest. These findings were also in line with prior research [24], which indicated that the free-breathing 3D VANE XD sequence not only effectively reduced motion artifacts but also enhanced structural visualization, thereby improving diagnostic confidence in vertebral lesion assessment.
Thus, in clinical practice, our study found that free-breathing 3D VANE XD sequence could offer three advantages. First, it reduces patient cooperation requirements by eliminating the need for breath-holding. Second, 91-second acquisition time improved examination efficiency. Thirdly, it enhanced vertebral lesion evaluation through superior SNR and image quality.
However, this study also has several limitations. First, the modest sample size, while is adequate for initial technical validation, but is lack of subgroup analysis by lesion pathology (e.g., tumors, infections, or degenerative changes), which necessitates further validation of the sequence’s generalizability. Second, the manual contrast agent administration might cause variations in dosage and injection rate, potentially affecting image quality, which should be compared with high-pressure injector administration in future.
Conclusion
The free-breathing 3D VANE XD sequence with radial k-space sampling significantly improves image quality in contrast-enhanced T1-weighted fat-suppressed MRI of the thoracic spine, facilitating more accurate clinical assessment and diagnosis of vertebral lesions.
Acknowledgements
Not applicable.
Abbreviations
- MRI
Magnetic resonance imaging
- 2D T1WI-mDixon-TSE
Two-dimensional T1-weighted imaging with modified Dixon turbo spin echo
- 3D T1WI-mDixon-GRE
Three-dimensional T1-weighted imaging with modified Dixon gradient echo
- 3D VANE XD
3D volumetric accelerated navigator echo with extended dynamic range
- CE
Contrast-enhanced
- NCE
Non-contrast-enhanced
- NSA
Number of signal averages
- CI
Confidence interval
- PE
Phase encoding
- SNR
Signal-to-noise ratio
- T2WI-mDixon-TSE
T2-weighted imaging with modified Dixon turbo spin echo
- zoom-DWI
Zoom diffusion-weighted imaging
- T2WI-TSE
Turbo spin-echo T2-weighted imaging
- ROI
Region of interest
- SI
Signal intensity
- SD
Standard deviation
- ICC
Intraclass correlation coefficient
Author contributions
Liuhong Zhu and Hao Liu jointly designed the research protocol, including the research objectives, methods, experimental design and MRI data collection. Weigen Yao collected the clinical data of each patient. Funan Wang and Yanwei Wang outlined all ROIs. Liuhong Zhu analyzed the data and wrote the draft of the manuscript, while Xiaobo Qu double checked the statistical results. Hao Liu and Jianjun Zhou revised the manuscript. All authors read and approved the final manuscript.
Funding
This work was supported by the Medical Innovation Project from the Fujian Provincial Health and Wellness Science and Technology Program (No. 2024CXB020).
Data availability
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
The study was conducted in line with the ethical guidelines of the Declaration of Helsinki. Following a thorough review of the entire study process and protocol, the Institutional Ethics Committee of Zhongshan Hospital (Xiamen) Fudan University reached a unanimous decision, and the study was granted approval under the number B2023-007. The additional scanning of the 3D VANE XD sequence had no impact on the subjects, and the final data were anonymized. Written informed consent was obtained from each subject prior to the examination.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Contributor Information
Hao Liu, Email: liuhaozsxm@163.com.
Jianjun Zhou, Email: zhoujianjunzs@126.com.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.