Research Presentation Session: Musculoskeletal

RPS 1910 - CT applications in musculoskeletal imaging

March 2, 12:30 - 13:30 CET

7 min
Value-added opportunistic chest CT screening for osteoporosis using bone mineral density estimation computed by multi-view semi-supervised learning
Jinrong Yang, Wuhan / China
Author Block: J. Yang1, H. Guo2, L. Le2, M. Xu2, H. Shuishi1, F. Yang1; 1Wuhan/CN, 2Hangzhou/CN
Purpose: The aim of the study was to evaluate the value of bone mineral density estimation computed by multi-view semi-supervised learning on chest CT for opportunistic osteoporosis screening.
Methods or Background: A total of 1295 patients who underwent chest CT for lung cancer screening and received dual-energy X-ray absorptiometry (DXA) during the same period were collected. They were divided into three groups: normal group, osteopenia group and osteoporosis group based on bone mineral density measured by DXA. And a new proposed indicator—bone mineral density estimation of all thoracic vertebrae and the first lumbar vertebra were automatically computed by multi-view semi-supervised learning on chest CT images. The differences of bone mineral density estimation were compared among the three groups. And the diagnostic efficacy for distinguishing osteopenia and osteoporosis from normal group were also evaluated.
Results or Findings: The bone mineral density estimation of thoracic and first lumbar vertebrae was significantly different among three groups and between any two groups (P<0.001), and decreased successively in normal group, osteopenia group and osteoporosis group. They were positively correlated with t-values of the first lumbar vertebrae (R = 0.58-0.77, P<0.01). And they had high diagnostic efficacy for distinguishing osteopenia and osteoporosis from normal group (AUC = 0.777~0.824).
Conclusion: The bone mineral density estimation of thoracic and first lumbar vertebrae, which computed by multi-view semi-supervised learning on chest CT, is of great value in the opportunistic screening of osteopenia and osteoporosis.
Limitations: The new marker—bone mineral density estimation can help patients realize the value-added value of chest CT, that is, during a chest CT examination, not only lung cancer can be screened, but also osteoporosis opportunistic screening can be realized. However, it was a single-center, retrospective study.
Funding for this study: No funding was obtained for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The ethical approval was obtained by the Ethics Committee of Wuhan Union Hospital ([2021]0853).
7 min
Multiparametric contrast-enhanced dual-energy CT as a one-stop shop approach in arthritis imaging-first results of the HAI-DECT study
Sevtap Tugce Ulas, Berlin / Germany
Author Block: S. T. Ulas, K. Ziegeler, J. Mews, U. Schneider, S. Ohrndorf, R. Biesen, D. Poddubnyy, F. N. Proft, T. Diekhoff; Berlin/DE
Purpose: This study aimed to evaluate the efficacy and diagnostic utility of contrast-enhanced dual-energy computed tomography (CE-DECT) in detecting and differentiating rheumatic joint diseases.
Methods or Background: Patients with suspected hand arthritis were prospectively enrolled. All underwent CE-DECT imaging alongside the standard clinical evaluation. CE-DECT (80/135 kVp) was captured pre and three-minutes post weight-adapted contrast agent application. Reconstructions included two-material decomposition for tophus imaging, virtual non-calcium for bone marrow edema, and CT-subtraction for soft-tissue inflammation. Diagnoses using CE-DECT were juxtaposed with the initial and final evaluations by referring rheumatologists. A subsequent survey assessed CE-DECT‘s diagnostic utility and impact on patient management, rated on a 1-10 scale. Descriptive statistics were employed.
Results or Findings: Out of 67 patients, diagnoses included rheumatoid arthritis (29), psoriatic arthritis (8), crystal disease (13) and others, for example osteoarthritis and peripheral spondyloarthritis (17). In 57 cases (85%), CE-DECT diagnoses aligned with final clinical evaluations. CE-DECT altered clinical diagnoses for 21 patients (31%). Rheumatologists rated CE-DECT‘s diagnostic utility at an average of 8.31 (SD 2.49) and its contribution to patient management at 8.61 (SD 2.19).
Conclusion: CE-DECT offers standardized arthritis imaging. Its diverse diagnostic capabilities make it a potent tool for early diagnosis in rheumatic joint diseases.
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 study was approved by the local ethics committee (EA1/183/21) and the Federal Office for Radiation Protection (ZD 3-22464/2021-285-G).
7 min
Risk factors for compression fractures in patients treated with gastrectomy: emphasis on bone mineral density measured on opportunistic CT
Suiji Lee, Seoul / Korea, Republic of
Author Block: S. Lee, K. W. Kim; Seoul/KR
Purpose: The aim of this study was to assess apply osteosarcopenia measurement methods in CT patients. Osteosarcopenia is the coexistence of osteoporosis and sarcopenia, which has a significant impact on the survival outcomes of critically ill patients. Many studies tried to diagnose osteosarcopenia using opportunistic CT. However, in case of patients treated with gastrectomy, the loss of bone mineral density and muscle mass is not routinely evaluated, even though these patients often experience bone and muscle shrinkage and subsequent compression fractures after surgery. Therefore, we assessed bone mineral density (BMD) and skeletal muscle area (SMA) in these patients by applying osteosarcopenia measurement methods in opportunistic abdominal CT.
Methods or Background: Among 2457 patients who had undergone gastrectomy between January 2003 and December 2010, we included 100 patients (mean age 58 years). Preoperative and 1-year postoperative abdominal CT scans were evaluated for BMD and SMA. Region of interest was situated in L1 vertebral body to estimate trabecular attenuation value to analyze BMD and SMA. To determine predictive risk factors for compression fractures, we implemented univariate logistic regression analysis.
Results or Findings: Between preoperative and postoperative CT, all patients showed a decline in the SMA (116 ± 27 cm2 vs. 110 ± 25 cm2, p<0.0001) and the BMD (177 ± 50 HU vs. 166 ± 50 HU, p<0.0001). Body weight (60 ± 9 kg vs. 54 ± 9 kg, p<0.0001) and BMI (24 ± 3 vs. 21 ± 3, p<0.0001) were also decreased. During the five-year follow-up record, five patients experienced osteoporotic vertebral compression fractures. Univariate analysis showed preoperative and postoperative BMD were significant risk factors for compression fractures, apart from age, sex, preoperative and postoperative SMA.
Conclusion: Preoperative and postoperative BMD measured on opportunistic CT are significant risk factors for compression fractures in patients treated with gastrectomy.
Limitations: Single center study and retrospective design.
Funding for this study: No funding was obtained for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by the IRB with the approval code: 2023-0976.
7 min
Photon-counting detector computed tomography (PCD-CT) for quantitative microstructural imaging of bone
Janina Maria Patsch, Vienna / Austria
Author Block: A. Burghardt1, A. Korajac2, A. E. Strassl2, S. Sadoughi1, G. Kazakia1, J. M. Patsch2; 1San Francisco, CA/US, 2Vienna/AT
Purpose: The goal of this study was to evaluate feasibility, performance and accuracy of PCD-CT for bone structure quantification. The quantification of bone quality by high-resolution research CT scanners (built for the peripheral skeleton) has been shown to improve fracture risk prediction. Now, photon-counting detector CT (PCD-CT) has been introduced as a clinical imaging tool with a generational advance in imaging performance.
Methods or Background: Cadaveric phantoms (n= 20 1-cm metaphyseal sections of distal radius and tibia) were imaged by μCT, 1st- and 2nd-generation HR-pQCT, and PCD-CT. PCD-CT scans were acquired at 120kVp in Ultra-High Resolution (UHR) mode (200mAs, 16.1mGy). A 15mm FOV was reconstructed across 1024x1024 matrix using the Br92 kernel (146μm pixel size, 150μm slice thickness). Spatial resolution (10% MTF) and noise performance (SNR) were measured in idealized density and wire phantoms. Standard density, geometry, and structure measures were quantified and evaluated for accuracy by linear regression & Bland-Altman analysis.
Results or Findings: PCD-CT provided an exquisite depiction of cortical and trabecular microstructure. PCD-CT noise performance (SNR=20.5) was superior to 1st- and 2nd-gen HR-pQCT research scanners (SNR=15.4 and 7.1). The spatial resolution of PCD-CT (10% MTF=132 μm) was comparable to 1st-gen HR-pQCT (10% MTF=138 μm), and inferior to 2nd-gen HR-pQCT (10% MTF=95 μm). Accuracy of PCD-CT was high (R2>0.9) for trabecular bone volume and trabecular number, and comparable to 2nd-gen HR-pQCT.
Conclusion: PCD-CT provides significant advantages for measuring human bone structure on a clinical device, including superior noise performance and scan time, while spatial resolution is comparable to 1st-gen HR-pQCT and accuracy was comparable to 2nd-gen HR-pQCT. PCD-CT represents an exciting opportunity to translate quantitative microstructural skeletal imaging to a clinical platform.
Limitations: Actual in vivo-translation (= in-vivo scanning) is work in progress.
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: Approval has been obtained for specimen donation and use.
7 min
Prediction of osteoporosis associated fractures: evaluation of dual-energy CT-derived metrics of the lumbar spine
Leon David Grünewald, Frankfurt a. Main / Germany
Author Block: L. D. Grünewald, V. Koch, S. Mahmoudi, P. Reschke, S. Martin, C. Booz, I. Yel, T. Vogl; Frankfurt a. Main/DE
Purpose: To assess the association of dual-energy CT (DECT)-derived bone mineral density (BMD) assessment with the occurrence of acute insufficiency fractures of the spine and follow-up fractures in a 2-year period.
Methods or Background: L1 of 160 patients (77 men, 83 women; mean age, 64.1 years, range, 19-94 years) who underwent dual-source DECT between 01/2016 and 12/2020 was retrospectively analyzed. For phantomless BMD assessment, a dedicated DECT postprocessing software based on material decomposition was manually applied. All depicted vertebrae were examined for signs of recent insufficiency fractures, and electronic health records were examined to obtain the incidence of osteoporotic fractures for a follow-up of 2 years after DECT. Receiver-operating characteristic (ROC) analysis was used to calculate AUC values, and logistic regression models were used to determine the associations of BMD, sex, and age with the occurrence of insufficiency fractures and follow-up fractures.
Results or Findings: A DECT-derived BMD threshold of 120.40 mg/cm³ yielded an AUC of 0.82 (p < .0001) to identify patients with one or more insufficiency fractures of the spine from patients without fracture, and a DECT-derived BMD cut-off of 93.70 mg/cm³ yielded an AUC of 0.9373 (CI, 0.867-0.977, p < .001) for the prediction of follow-up fractures within 2
two years after DECT. A lower DECT-derived BMD was associated with an increased risk to sustain insufficiency (Odds ratio of 0.93, 95% CI, 0.91-0.96, p < .001), and follow-up fractures (Odds ratio of 0.8710, 95% CI, 0.091-0.9375, p < .001), indicating a protective effect of increased DECT-derived BMD.
Conclusion: Dual-energy CT-derived bone mineral density assessment from routine examinations can be used to stratify the risk of sustaining osteoporosis-associated fractures following acute trauma and during a follow-up period of 2 years.
Limitations: Preselection Bias, Limited to Dual-Energy-CT, Retrospective Study
Funding for this study: No funding was obtained for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: Informed consent waived due to retrospective nature.
7 min
Cone beam CT in the emergency department: revising incidence rates for carpal bone fractures
Sophie Murphy, Dublin / Ireland
Author Block: S. Murphy, E. McDermott, B. Gibney, P. J. Macmahon; Dublin/IE
Purpose: The aim of this study was to evaluate and quantify the incidence of acute radio-carpal fractures when routinely employing CBCT in a major trauma centre.
Methods or Background: In our institution Cone beam computed tomography (CBCT) is routinely utilised in the Emergency Department (ED) to investigate patients who have suspected acute radio-carpal fractures but negative x-rays. We have noted that the frequency of wrist fractures as published in the literature does not match the frequency encountered in clinical practice when using CBCT to investigate these patients. A retrospective analysis was conducted on all CBCT scans performed for wrist trauma in the ED between January 2018 and August 2023. Fracture incidence, type, and specific carpal bone locations were characterized.
Results or Findings: A total of 690 wrist CTCBs were performed on ED patients across the study period.
52% were female with a mean age of 44.5 years. Forty four percent (306/690) were positive for a fracture even though x-rays were negative, and 24% (72/306) of positive studies had more than one fracture identified. A total of 386 discrete fractures were identified and characterised like this: 62% Carpal bones (240), 24% Distal radius (93), 10%Metacarpal bone (38), 4% Distal Ulna (15). Of the 240 carpal bone fractures: 29%Trapezium (70), 29% Scaphoid (69), 22% Triquetral/triquetrum (53), 8% Hamate (18), 4% Pisiform (9), 3% Trapezoid (8), 3% Capitate (7), 3% Lunate (6).
Conclusion: Our data indicates that a revision in the conventional carpal bone fracture incidence estimates is needed, suggesting a much higher frequency of certain carpal bone fractures (esp trapezium) when CBCT is used as the imaging modality in wrist trauma assessment.
Limitations: Single centre study.
Funding for this study: No funding was obtained for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: Not applicable
7 min
Potential of dual-energy CT-based collagen maps for the assessment of thoracic disc degeneration
Leon David Grünewald, Frankfurt a. Main / Germany
Author Block: S. Mahmoudi, L. D. Grünewald, V. Koch, J-E. Scholtz, S. Martin, D. Pinto Dos Santos, C. Booz, T. Vogl, I. Yel; Frankfurt a. Main/DE
Purpose: The objective of this study was to assess the potential of Dual-Energy CT (DECT)-derived collagen maps for the assessment of disc degeneration in the thoracic spine.
Methods or Background: We retrospectively included 51 patients who received both dual-source DECT (third generation dual-source DECT; Somatom Force; Siemens Healthineers) and MRI of the thoracic spine within two weeks between July 2020 and October 2022. Disc degeneration was independently evaluated by two blinded readers in DECT-derived collagen maps. Based on the Pfirmann grading system, thoracic disc generation was classified into no/mild (Pfirmann Grade 1&2), moderate (Pfirmann Grade 3&4), and severe (Pfirmann Grade 5). To assess the diagnostic value of DECT-derived color-coded collagen maps for the evaluation of thoracic disc degeneration, we calculated diagnostic accuracy, sensitivity and specificity using MRI as reference standard. 5-point Likert scales were used to evaluate diagnostic confidence (1=insufficient,2=low,3=moderate,4=high,5=excellent) and image quality (1=non-diagnostic,2=weak,3=moderate,4=good,5=excellent) subjectively.
Results or Findings: In total, 612 intervertebral discs from 51 patients were evaluated (mean age, 68±16 years, 23 female). MRI depicted 135 non/mildly degenerated discs (22.1%), 470 moderately degenerated discs (76.8%), and seven severely degenerated discs (1.1%). Collagen maps achieved a high level of sensitivity (792 of 954 [83.0 %], specificity (221 of 270 [81.9 %]), and diagnostic accuracy (1013 of 1215 [83.4 %]) to discriminate between non/mild and moderate/severe thoracic disc degeneration. Inter-reader reliability was substantial (κ=0.82) for DECT collagen maps (p<.001). The subjective evaluation of disc degeneration using DECT-derived collagen maps showed moderate to high diagnostic confidence (median 3.5, interquartile range (IQR) 3-4) and moderate to good image quality (median 3.5, IQR 3.5-4).
Conclusion: The ability of DECT-derived collagen maps to evaluate the degree of disc degeneration may facilitate assessment of thoracic disc degeneration in patients with disc-related pathologies when MRI is not available.
Limitations: Not applicable for this study.
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 ethical review board of our institution approved this retrospective study and waived written informed consent.

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