RPS 510 - Upper extremities and tumours

Author Block: R. P. Marcus, G. C. Feuerriegel, A. A. Marth, D. Nanz, R. Sutter; Zurich/CH
Purpose: This study aimed to assess the diagnostic performance of accelerated MRI acquisition with deep-learning reconstruction and edge sharpening in patients after rotator cuff repair.
Methods or Background: Unenhanced MRI scans of the operated shoulder were performed on 116 patients using a 3 Tesla (T) scanner (Magnteom Prisma, Siemens Healthineers). Standard and accelerated protocols were used during the same scanning session acquiring three sequences in coronal plane (STIR, PD TSE and PD FS), two sequences in sagittal plane (STIR and T1 TSE), and one sequence in axial plane (PD FS) with a slice thickness of 3mm each. The acquisition times of the standard and the accelerated protocols were recorded. Two experienced radiologists, blinded to the acquisition protocol, evaluated postsurgical changes of the tendons as per Sugaya classification (1: sufficient thickness, 2: sufficient thickness with partial high intensity, 3: insufficient thickness, 4: minor discontinuity, 5: major discontinuity).
Results or Findings: Interrater and intrarater reliabilities of the evaluated 207 operated tendons were strong (Kappa=0.824-0.863). The accelerated protocol reduced the acquisition time by 80% (3.7mins (2.5-6.3) vs. 18.4mins (17-33.7) for accelerated vs. standard protocol, p<0.001). A total of four intrarater disagreements were observed (2%), mostly due to motion artifacts in the standard acquisition. No motion artifact was recorded during the accelerated protocol.
Conclusion: Accelerated MRI acquisition with deep-learning reconstruction and edge sharpening significantly shortened the acquisition time while an excellent depiction of evaluating the condition of the shoulder after rotator cuff repair.
Limitations: This study has a small sample size.
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 was approved by a local Ethics Committee in the Canton of Zurich.

Author Block: L. J. Moser¹, J. Pitteloud¹, V. Mergen¹, D. Frey¹, T. Nowak², O. Distler¹, M. Eberhard³, H. Alkadhi¹; ¹Zurich/CH, ²Forchheim/DE, ³Unterseen/CH
Purpose: This study aimed to evaluate the feasibility and accuracy of bone mineral density (BMD) quantification from spectrally acquired localiser radiographs (LRs) with photon-counting detector (PCD)-CT, in comparison with DXA.
Methods or Background: For this experimental study, spectrally-resolved LRs on a clinical dual-source PCD-CT scanner (NEAOTOM Alpha, Siemens) acquired with 140kVp and with four different tube currents (10mA, 20mA, 30mA and 40mA) of the European Spine Phantom were obtained. Scans were repeated three times. We used two setups: (A) the phantom placed directly on the CT table and (B) the phantom submerged in water with an anterior-posterior diameter of 30cm simulating a slightly overweight patient. Corresponding DXA scans were acquired. Assessment of aBMD in LRs was enabled by leveraging the spectral information with material decomposition maps for hydroxyapatite and water. The spine phantom-supplied values were used as the reference standard.
Results or Findings: The mean absolute error (MAE) in setup A for LR-derived aBMD across all tube currents and vertebrae was 0.003g/cm2 with a relative difference of ΔaBMD ranging from -1.5% to 1.1%. Coefficients of variance (CV) were below 1% stratified for tube current in setup A. In setup B, the MAE was 0.018g/cm2, and the ΔaBMD ranged from +1.0% to +5.3%. CV was below 3% for all tube currents and below 2% excluding 10mA. The absolute error of DXA scans in both setups (-0.041g/cm2 for setup A, -0.06g/cm2 for setup B) was higher than corresponding MAEs from PCD-CT.
Conclusion: Our phantom study indicates that LRs obtained with PCD-CT enable the calculation of BMD with high accuracy.
Limitations: This was a phantom study and represents pre-clinical software to reconstruct raw data from LRs.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: This study was performed on a phantom.

Author Block: M. Haenen, E. Teule, S. Hummelink, I. Sechopoulos, B. van der Heijden; Nijmegen/NL
Purpose: This study aimed to analyse wrist kinematics in healthy and scapholunate interosseous ligament (SLIL) injured wrists using four-dimensional computed tomography (4DCT) and a fully automated motion analysis algorithm.
Methods or Background: 4DCT scans of 41 healthy wrists and eight wrists with arthroscopically-confirmed Geissler 4 SLIL injuries were acquired. Each scan consisted of one conventional static CT image and two dynamic imaging sequences; wrist radial-ulnar deviation (RUD) and flexion-extension (FE). Scanner rotation time was 0.275s, and acquisition parameters include 80 kV and 40 mAs. A sampling rate of 10Hz resulted in 144 dynamic 4DCT frames per wrist. Bones were automatically segmented in each frame using an artificial intelligence-based algorithm, and the scapholunate distance (SLD) and sagittal scapholunate angle (SLA) were automatically estimated per dynamic frame and resampled to a uniform distribution of wrist positions for intersubject comparison. The median and maximum SLD and SLA values were calculated. A Mann-Whitney U test was employed to compare both groups.
Results or Findings: The median and maximum SLDs and SLAs were significantly larger in the injured group compared to the healthy group. For example, the median and interquartile range were as follows: RUD (SLD) 2.49mm [1.36-3.40mm] vs 0.86mm [0.64-1.06mm], p<.001; RUD (SLA) 93.0⁰ [83.8-103.0⁰] vs 69.2⁰ [62.3-74.1⁰], p<.001 and FE (SLD) 1.99mm [1.31-3.23mm] vs 0.92mm [0.71-1.17mm], p<.001; FE (SLA) 92.3⁰ [66.6-102.3⁰] vs 71.9⁰ [57.0-85.2⁰], p<.001).
Conclusion: 4DCT is an emerging modality that enables non-invasive analysis of wrist motion. SLDs and SLAs automatically estimated from 4DCT scans during wrist motion could be used to diagnose SLIL injuries non-invasively.
Limitations: The small sample size of injured wrists and the lack of independent validation of quantitative estimates limit this study.
Funding for this study: This study was internally funded.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved with the ABR number: NL72518.091.19.

Author Block: G. Timoçin Yığman, A. Peker, Y. E. Senturk, H. Özen Atalay; Istanbul/TR
Purpose: The aim of this study was to investigate the relationship between quantitative DCE-MRI and intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) parameters in patients with soft tissue sarcomas (STS).
Methods or Background: From March 2022 to August 2023, patients were included who were histopathologically diagnosed as STS in our centre and who had a DCE-MRI and IVIM-DWI. Patients with a history of chemotherapy or radiotherapy before MRI and patients with a diagnosis of liposarcoma were excluded. Two radiologists with specific musculoskeletal imaging experience evaluated all the exams (3 and 4 years). Patients' age, gender, and the longest diameter of the mass (LD) were noted. DCE-MRI measurements were made from the Ktrans maps, avoiding bleeding, necrosis, and cystic areas. ROIs were placed the area with the highest perfusion in both. Permeability parameters of the masses (Ktrans, AUC, Kep, Ve) were noted. IVIM-DWI was obtained using axial EPI with 11-b values. IVIM-DWI was processed semi-automatically using Syngo.via V8.5 Frontiers (Siemens, Germany) and FD, D, and DP (D*) were calculated.
Results or Findings: Ten patients, two females and eight males, were included. The mean age of the patients was 58±15.05 (23-70), and the mean LD was 124±66.44 mm (56-280). Interobserver agreement was excellent for DCE-MRI and good for IVIM-DWI parameters. There was a strong correlation between K trans and FP (r=0.76; p=0.011), Kep and DP (r=0.77; p=0.009), and AUC and FP (r=0.72; p=0.020). No significant correlation was observed in other parameters.
Conclusion: No study in the literature compares IVIM-DWI and DCE-MRI parameters in tumours. Our study demonstrated a strong correlation between parameters. Studies with larger patient groups are needed to correctly interpret IVIM-DWI parameters and replace DCE-MRI.
Limitations: The study is limited by the small number of patients from a single centre.
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 was approved by the Koc University Biomedical Research Ethics Committee, Istanbul.

Author Block: V. Potočnik Tumpaj, G. Omejec, Ž. Snoj; Ljubljana/SI
Purpose: This study aimed to compare the long-term treatment effects of ultrasound (US)-guided five per cent dextrose and corticosteroid injections in patients with carpal tunnel syndrome (CTS).
Methods or Background: We prospectively recruited 57 patients with mild to moderate bilateral CTS. Symptom severity and functional status were assessed with the Boston Carpal Tunnel Questionnaire (BCTQ) and visual analogue scale (VAS). Electrodiagnostic studies (EDx) and median nerve US were performed. For the left wrist, injectate was randomly selected (6ml of five per cent dextrose or 2ml of corticosteroid mixed with 4ml saline). Afterwards, the right wrist was injected with the remaining solution. Patients and examiners were blinded to the selection of the solution. Follow-up was performed at one, three, six, and 12 months.
Results or Findings: Both solutions demonstrated significant improvement for clinical outcome in VAS (at one, three and six months follow-up; p<0.05) and BCTQ score (at one, three, six, and 12 months follow-up; p<0.05) compared to baseline. No changes in median nerve cross-sectional area (CSA) were present, however, the flattening ratio significantly improved at three, six, and 12 months follow-up (p<0.05). No significant difference was present between solutions at each follow-up (p>0.05).
Conclusion: Ultrasound-guided carpal tunnel injections of corticosteroids and five per cent dextrose significantly improve clinical outcomes in patients with CTS up to one-year follow-up. No differences were present between solutions.
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: This study was approved by the Slovenian National Ethics Committee.

Author Block: V. Di Martino, N. Di Meglio, A. Perrella, G. Bagnacci, C. Sica, M. A. Mazzei; Siena, SI/IT
Purpose: We report six cases of bone lymphoma presenting with lower back pain which occurred over a two year period, from 2020 to 2022, in our centre. This study highlights relevant imaging features with a special focus on MR.
Methods or Background: Bone lymphoma presenting with musculoskeletal pain is an often challenging diagnosis because its imaging features are nonspecific. It is classified either as primary bone lymphoma (PBL, no other extraosseous site involved), or secondary bone involvement in systemic lymphoma (SBL, secondary bone lymphoma). SBLs are much more frequent (30-50% of all non-Hodgkin Lymphomas, NHLs, and 5- 10% of all Hodgkin Lymphomas, HLs), while primary bone lymphomas are rare (<5% of primary bone tumours and 1% of all NHLs, more often a form of diffuse large B cell lymphoma, DLBCL).
Results or Findings: Four females and two males (aged 21 to 80 years) with persistent lower back pain underwent an MRI and subsequently a body contrast-enhanced CT and/or a PET/CT. The diagnosis was confirmed with a biopsy: four PMLs (DLBCL), two SBLs (one HL and one NHL). In all cases bone lesions were characterised by marked signal hypointensity on T1-weighted MRI corresponding to heterogeneous hyperintensity on T2-weighted images, asymmetric, not confined to the subchondral bone and, in two cases, also associated with soft tissue involvement but without significant cortical bone destruction. In four cases bone lesions were visible at CT with a permeative or lytic pattern. Both cases of SBL presented systemic symptoms as well (fever and night sweats).
Conclusion: Bone lymphoma should always be considered in the differential diagnosis of patients presenting with lower back pain, especially if the imaging features of bone lesions are atypical or associated with fever, night sweats, and weight loss.
Limitations: This study is limited by its case series methodology.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No information provided by the submitter.