Research Presentation Session: Musculoskeletal

RPS 2210 - Bone density and spine imaging

March 3, 08:00 - 09:00 CET

7 min
Application of a novel ultra-high resolution photon counting detector CT in assessing thoracolumbar vertebral anatomic structures
Yufei Huang, Shanghai / China
Author Block: Y. Huang; Shanghai/CN
Purpose: The purpose of this study was to evaluate the feasibility of ultra-high resolution (UHR) scanning on photon counting detector CT (PCD-CT) for assessing thoracolumbar vertebral anatomic structures.
Methods or Background: During September 2023, 20 patients underwent the UHR thoracolumbar scanning on PCD-CT utilising a standard resolution (SR) reconstruction with a thickness of 1 mm and an increment of 0.7 mm, and a UHR reconstruction of 0.2 mm for both thickness and increment. All images were reconstructed by the kernel of Br60, Br80, Br84 and Br89. The radiomic features were extracted and the slope of grey values across the vertebral cortex were calculated. The image quality was subjectively analysed by a Likert 5-point scale.
Results or Findings: The radiomic features associated with the demonstration of anatomical structures indicated that UHR images outperformed SR images with statistical significance (p<0.001). The slope of grey values across the vertebral cortex of UHR images was highest in UHR images with Br89 (1553.4 [1169.0], p<0.001) and Br84 (1643.5 [1402.5], p<0.001). Image noise significantly increased in UHR images with a high level of kernel. The subjective evaluation revealed that UHR images with Br84 had the best display of bone trabeculae and cortex (5 [0], p<0.001). Moreover, Br84 (5 [0]) and Br89 (5 [0]) had the highest demonstration of spatial resolution (p<0.001).
Conclusion: It is feasible to perform thoracolumbar UHR scanning on PCD-CT, and Br84 is the best kernel to improve the spatial resolution and visualisation of vertebral trabecular microstructure. Thoracolumbar vertebral imaging seems particularly likely to benefit from the advantages of PCD-CT in the clinical scenario in the future.
Limitations: Due to ethical issues, it is not possible to compare the image quality of conventional scanning images on energy-integrating detector CT and UHR scanning images on PCD-CT in the same patient.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by the ethics committee reference number: 186
7 min
Association between haemochromatosis genetic variants and vertebral fracture: a UK Biobank study
Lucy Banfield, Exeter / United Kingdom
Author Block: L. Banfield, K. Knapp, D. Melzer, J. Atkins; Exeter/UK
Purpose: Haemochromatosis is caused by the p.C282Y homozygous variant resulting in iron overload. Previous studies demonstrate increased risks of osteoporosis, back pain and femoral fracture in male homozygotes. The objective of this study was to review the prevalence of vertebral fracture (identified on iDXA) by genotype, in a large community cohort.
Methods or Background: Lateral spine iDXA scans (GE-Lunar) acquired from UK Biobank were assessed. A subset of 292 participants; 146 pC282Y homozygotes and 146 age, BMI and sex matched controls were randomly selected. Images were reviewed for radiological evidence of vertebral fracture using the Genant Semi-Quantitative Scale. Descriptive analysis and logistic regression models assessed for associations between genotypes and incidence of vertebral fracture, adjusting for age and stratified by sex. Bone mineral density (BMD) scores were also reviewed for participants with reported fractures.
Results or Findings: 37 vertebral fractures (12.9%) were identified with 20 (14.0%) in the p.C282Y homozygotes and 17 (11.8%) in the wildtype. Vertebral fractures were twice as common in C282Y homozygous men (n=10, 18.2% vs n=5, 8.9%) but not higher in women (n=10, 11.4% vs n=12, 13.6%) however, age-adjusted logistic regression suggests this is not statistically significant in males (OR: 2.34 [0.73-7.42, p=0.15]) although numbers were small.

There was also no significant difference in BMD between the homozygotes and the wildtypes: Lumbar spine T-score –0.21 versus 0.34; p=0.50, femoral neck T-score –1.03 versus -1.09 respectively; p=0.94.
Conclusion: There may be an increased prevalence of vertebral fracture in the male p.C282Y homozygotes in the absence of diminished BMD when compared to those with no genetic mutations, but this was not statistically significant and further work is needed in a larger cohort.
Limitations: The study used a volunteer population, so may be biased towards healthier individuals.
Funding for this study: Janice L. Atkins is supported by a National Institute for Health and Care Research (NIHR) Advanced Fellowship (NIHR301844). David Melzer, Karen M. Knapp, and Lucy R. Banfield are supported by the University of Exeter.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Ethical approval for UK Biobank was obtained from the North West Multi-Centre Research Ethics Committee.
7 min
MRI or low-dose CT in suspected axial spondyloarthritis: preliminary results of a comparative study
Dominik Deppe, Berlin / Germany
Author Block: D. Deppe, S. T. Ulas, M. Koka, F. N. Proft, M. Protopopov, L. Spiller, V. Rios Rodriguez, D. Poddubnyy, T. Diekhoff; Berlin/DE
Purpose: This study aimed to evaluate and compare the diagnostic efficacy of magnetic resonance imaging (MRI) and low-dose computed tomography (CT) in patients with suspected axial spondyloarthritis (axSpA). In a standard setting, patients undergo radiography and subsequent MRI, when the radiograph is negative. CT is used in unclear cases, however, it’s gaining more attention since the introduction of low-dose techniques.
Methods or Background: 86 patients with suspected axSpA were randomised into two arms: 1. MRI-first (followed by CT if MRI was negative) and 2. CT-first (followed by MRI if CT was negative). Positive imaging was defined by the unambiguous identification of active inflammatory (bone marrow oedema according to the updated ASAS definition suggestive of axSpA) or structural lesions (e.g. extensive erosions or ankylosis suggestive of axSpA), rated in consensus reading by two radiologists specialised in musculoskeletal imaging.
Results or Findings: In the MRI-first arm (48 patients), MRI was positive in 11/48 (23%) patients. Subsequent CT in 37 patients showed no positive results (0/37; 0%). In the CT-first arm (38 patients), CT was positive in 12/38 (32%). Subsequent MRI (26 patients) was positive in one (1/26; 4%).
Conclusion: MRI and low-dose CT demonstrated comparable diagnostic performance in patients with suspected axSpA.
Limitations: If initial imaging was positive, subsequent imaging was not performed which limits the analysis.
Funding for this study: No funding was provided for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by the local ethics committee (EA1/145/22).
7 min
Straightening out scoliosis: how artificial intelligence assisted Cobb angle measurements on spine radiographs can support the clinical user
Willem Grootjans, Leiden / Netherlands
Author Block: W. Grootjans1, S. Challiui1, A. Bubberman1, C. Salzlechner2, D. Ehinger2, K. van Langevelde1; 1Leiden/NL, 2Vienna/AT
Purpose: Quantitative assessment of scoliosis using Cobb angles on spine radiographs is, albeit labour-intensive, commonly performed in radiology practices. This study aimed to assess the added value and clinical impact of automating Cobb angle measurements using artificial intelligence (AI).
Methods or Background: A total of 100 anteroposterior spine radiographs were retrospectively analysed with a fully automated software solution based on deep learning (SQUIRREL, version 1.0, ImageBiopsy Lab, Vienna, Austria). Automatically determined Cobb angles and range of the spinal curvature were compared to manual measurements. User interaction for AI (un)assisted Cobb angle measurements was monitored using specially designed mouse-tracking software in 20 cases. Time per case, number of mouse clicks, and mousing distance were recorded. Differences were reported as mean±SD (change %).
Results or Findings: The acceptance rate of automated Cobb angle measurements was 93%. Rejected cases were due to the presence of metal implants or unrealistic measurements. For accepted cases, the mean difference in automatic and manually determined Cobb angles was 3.7°±3.4, while the mean difference in upper and lower vertebral position was 1.2±1.5 and 0.8±1.1 respectively. Without AI, the mean number of left, right and middle mouse button (LMB, RMB, MMB) clicks was 32.2±7.0, 1.9±0.5, and 1.9±2.0 respectively. Mean mousing distance and time per case were 48620±22698 pixels and 66.9±18.0 seconds respectively. Supporting the user with AI resulted in a mousing distance and time per case of 13868±2486 (-29%) and 29.2±4.7 (-44%) seconds respectively. The mean number of LMB and RMB clicks were 11.3±2.2 (-35%) and 0.4±0.9 (-21%) respectively, while MMB was not used.
Conclusion: Automated analysis of Cobb angles by AI-software showed excellent performance. Automation with AI modifies user behaviour and reduces the physical effort required to report a case in clinical practice.
Limitations: Data on a single experienced user was reported. Further studies extend these experiments to different users.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by the institutional ethics commitee (reference number: 20231010001).
7 min
Assessment of the predictability of vertebral fractures in multiple myeloma in dual-layer CT (DLCT) with virtual non-calcium (VNCa) CT images and calculation of virtual calcium-only (VCa) images
Thuy Duong Do, Heidelberg / Germany
Author Block: S. Brandelik1, S. Rahn1, M. Merz2, W. Stiller1, S. Skornitzke1, C. Melzig1, H-U. Kauczor1, T. F. Weber1, T. D. Do1; 1Heidelberg/DE, 2Leipzig/DE
Purpose: This study aimed to assess the predictability of vertebral fractures in multiple myeloma in dual-layer CT (DLCT) with virtual non-calcium (VNCa) CT images and the calculation of virtual calcium-only (VCa) images.
Methods or Background: 81 patients with plasma cell dyscrasia and whole-body DLCT at the time of diagnosis and follow-up spine imaging were included in the study. Conventional CT images (CI), VNCa images with calcium suppression (CaSupp) indices 25 and 100, and the novel method of calculated VCa images by subtraction of CaSupp100 - CaSupp25 were quantitatively analysed using region-of-interests in the vertebral bodies L1-L5 and all vertebral bodies with fractures on baseline or follow-up imaging. Logistic regression analyses were performed to assess the predictability of imminent spine fractures. For model comparisons, the Akaike information criterion and R² were consulted.
Results or Findings: New fractures were seen in 24 patients' follow-up imaging. Predictability of new vertebral fractures was significant for baseline assessment of CT numbers in CI, CaSupp 25 VNCa, and VCa (p=0.01, respectively) with a higher risk for new fractures in case of lower CT numbers in CI and VCa (Odds ratio 0.982 [0.969;0.994], 0.987 [0.978;0.995]) and in case of higher CT numbers in CaSupp 25 (Odds ratio 1.015 [1.006;1.026]). Direct model comparisons implied that CT numbers in CaSupp 25 and VCa might show better fracture prediction than in CI (R2=0.18 both vs. 0.15; AICc=91.95, 91.79 vs. 93.62). Neither age, gender nor pre-existing fractures improved the fracture predictability when included in the calculation.
Conclusion: VNCa and calculated VCa images in DLCT are feasible to predict imminent vertebral fracture risk in MM patients.
Limitations: This study was limited by the number of patients.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This retrospective exploratory single-centre study was approved by the local review board (application number: S-348/2019). The need for written informed consent was waived.
7 min
The role of dynamic magnetic resonance imaging in improving the diagnostic accuracy of degenerative diseases of the lumbosacral spine
Abdelfattah Saoud, Cairo / Egypt
Author Block: N. Ibrahim, A. Saoud, M. Yosry, A. Yassin; Cairo/EG
Purpose: This study aimed to evaluate the role of dynamic MRI in the assessment of lumbar spine degenerative diseases compared to conventional MRI regarding the detection of spinal instability and evaluating the degenerative changes in flexion and extension in comparison to a neutral position to determine the best clinical management and outcome for the patients.
Methods or Background: A prospective study conducted on symptomatic patients with degenerative spine referred to MRI. They underwent imaging in neutral, flexion and extension positions. AP diameter of the spinal canal, foraminal height and area, lumbosacral angle and lordotic angle were measured and used as a comparative index. Correlation with patients' symptomatology and outcome were analysed.
Results or Findings: Dynamic MRI evoked radiological findings explaining the patients’ clinical picture in 32.4% of the patients. 25% showed a narrowing of the neural foramina dimensions that could be elicited on dynamic images only. 25% of spinal canal stenosis was induced by the positional change and 50% showed spinal instability either in flexion or extension position. 70.3% had conservative management with pain improvement after 3 months of compliance. In 24.3% of the patients, the treatment plan was changed from conservative to surgical intervention after performing dynamic MRI of which 75% showed improvement after surgery. The evaluation of the patient’s pain level and outcome after management taken according to the dynamic MRI results showed significant improvement (p-value 0.01).
Conclusion: Dynamic MRI of the lumbar spine allows better detection of hidden pathologies in conventional MRI in patients with clinical/radiological mismatches. It gives the surgeon a tool to understand patients’ symptomatology. It also provides evidence of neural compression and facilitates accurate preoperative planning regards the procedure and the target level, and accordingly better postoperative outcome.
Limitations: This study had a small patient population and there was a lack of long-term follow-up of some of the patients.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study has the approval number MS 85/2023.
7 min
Opportunistic screening of osteoporosis using routine lumbar spine MRI: a retrospective comparative study
Naser Mohammad Issa Obeidat, Irbid / Jordan
Author Block: L. Rousan, N. M. I. Obeidat, N. Abdo, L. Alshraa, T. Ajam, H. Al-Zoubi, H. Saif, A. Albaqshi; Irbid/JO
Purpose: Multiple studies compared T-scores obtained from BMD with different MRI protocols depending on the SNR ratio of the lumbar vertebral bodies. This study aimed to assess whether routine sequences of the lumbar spine MRI can predict the presence of osteoporosis by visually assessing the alteration of the signal intensity alone.
Methods or Background: A 322 cohort of patients who underwent both lumbar spine MRI and DEXA scan within a 6-month interval between January 2015 and December 2022 were selected. Three radiologists graded L4 (or L3) vertebral body fat content into ≤50% or >50% based on visual estimation of its bone marrow signal intensity on sagittal T1 weighted sequences. Average vertebral body bone marrow signal intensity was also obtained. MRI interpretation results were compared with DEXA scan reports after grouping patients into three categories (normal, osteopenia, and osteoporosis). Statistical analysis was performed and a p-value of <0.05 was considered significant.
Results or Findings: 322 patients were enrolled in the study (80.4% females, average age 57 years). 10.2% of which had osteoporosis, but the majority had a normal T-score (54.7%). MRI interpretation yielded 167 and 155 patients with a score of ≤50% and >50%, respectively, with an average signal intensity of 727. There was a significant statistical correlation between each of the MRI readings (estimated fat percentage and bone marrow signal intensity) with the diagnosis of reduced bone density on the DEXA scan (p-value of 0.0008 and 0.028, respectively).
Conclusion: Our results showed that routine lumbar spine MRI studies can predict reduced bone density and, hence proved to be beneficial in opportunistic screening for osteoporosis. These results are of considerable interest in suggesting the silent disease of osteoporosis in the most requested musculoskeletal MRI scan.
Limitations: No limitations were identified.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The institutional review board approved this study and waived the need for written consent (Approval No. 38/123/2019).

This session will not be streamed, nor will it be available on-demand!