Skeletal Radiology最新文献

Objectives: This study aimed to identify quantitative MRI features through radiomic analysis and to develop predictive models for determining the histological grade of myxoid liposarcoma (MLS).

Materials and methods: This retrospective single-center study included 57 patients with histologically confirmed MLS (30 low-grade, 27 high-grade). Tumors were segmented and 107 radiomic features were extracted from T1-weighted imaging (WI), T2-WI, short tau inversion recovery (STIR), apparent diffusion coefficient (ADC) maps, and contrast-enhanced (CE) images with and without fat saturation (FS). Features showing statistical significance (p < 0.05) were selected and used to develop predictive models, whose performance was assessed using cross-validation and reported as area under the curve (AUC).

Results: Mean age was 51.6 ± 14.7 years (32 men, 25 women). Radiomic analysis identified three significant features for T1-WI and STIR and 19 for T2-WI. For CE-T1-WI, CE-T1-FS-WI, and CE-3D, four, six, and three features were significant, respectively. Models based on T2-WI and CE-3D achieved the highest performance (AUC up to 0.88). Additional models trained exclusively on institutional T1-WI and T2-WI showed reduced performance on external validation, although AUCs improved when applied to patients scanned with the same vendor.

Conclusion: Radiomic analysis of pre-treatment MRI shows promising results in predicting histological grade of MLS. This study is novel in addressing grading rather than diagnosis alone, a distinction with clear clinical relevance for treatment planning and prognostic assessment. In particular, models based on T2-WI may complement conventional imaging and histopathology by providing whole-tumor quantitative grading, while multicentric validation is required for clinical application.

Objectives: To evaluate the diagnostic success of image-guided core needle biopsy (ICNB) of bone and soft tissue lesions in the pediatric population and what factors influence diagnostic success.

Methods: For 370 biopsies performed on 350 patients 18 years of age and younger, the diagnostic yield (proportion of biopsies histopathologically sufficient for diagnosis) and accuracy (proportion of biopsies in which ICNB specimen concordant with the reference standard histopathology from surgical excision) of the biopsies, as well as a series of patient, lesion-related, and technical factors, were retrospectively analyzed. Multivariate statistical analysis was performed to evaluate what factors predicted diagnostic yield and accuracy.

Results: Diagnostic yield was 95.1% (213/224) for bone biopsies and 97.1% (132/136) for soft tissue biopsies. Diagnostic accuracy was 93.1% (27/29) for bone biopsies and 88.4% (38/43) for soft tissue biopsies. Lesions of suspected benign etiology were found to be associated with lower diagnostic yield (OR = 15.2, p = 0.002) for bone biopsies, and increased total core length (OR = 3.3, p = 0.047) was found to be associated with higher yield for soft tissue biopsies. Increased needle gauge (OR = 2.9, p = 0.03) was found to be associated with higher accuracy for bone biopsies, and using a manual drill (compared to a battery-powered drill) was associated with lower accuracy (OR = 0.03, p = 0.03). Overall, 88.9% (32/36) of samples from the biopsy were sufficient for additional cytogenetic analysis. Complications occurred in 0.3% (1/370) of biopsies.

Conclusions: ICNB has a high rate of diagnostic success and a low complication rate and should be considered an alternative to open biopsy.

Gore-Tex or expandable polytetrafluorethylene (ePTFE) was commonly used for synthetic ACL and PCL graft reconstruction in the late 1980s, but was discontinued owing to high failure rates and osteolytic complications. While this is an uncommon complication within the initial 20 years of post-graft implantation, the effects of these ligaments at much longer follow-up have little documentation due to increasing rarity. We present a case of a 64-year-old male with massive osteolysis first suspected to be extensive subchondral cystic changes secondary to advanced osteoarthritis. Two years after the initial presentation of knee pain, the patient represented with a tibial plateau fracture through the massive osteolytic lesion. CT imaging and pathology favored particle wear osteolysis secondary to the implanted grafts. The patient was treated with partial graft removal and TKA with a revision-style tibial stem. This case highlights the rare, long-term complications of synthetic ligament grafts, including progressive osteolysis and pathologic fracture decades after implantation. Synthetic graft-related osteolysis should be considered in patients with a remote history of graft reconstruction presenting with late-onset joint instability or fractures. CT imaging is crucial in evaluating the degree of osteolysis as a staged surgical approach with bone grafting may be necessary for severe cases.

Objective: To evaluate differences in apparent diffusion coefficient (ADC) values between benign and malignant primary pediatric bone tumors and to assess their diagnostic accuracy in differentiating these tumors.

Materials and methods: We retrospectively analyzed MRI scans of 96 pediatric patients (54 males, 42 females; mean age 12.97 ± 3.9 years) with primary bone tumors who underwent diffusion-weighted imaging, including 48 benign and 48 malignant tumors. We measured ADCmean, ADCmin, and ADCmax of the solid tumor part, carefully avoiding cystic, necrotic, or sclerosed tumor areas. The Wilcoxon rank-sum test was used to test the distributional difference of benign vs malignant tumors. ROC curve analysis was performed to assess the diagnostic accuracy. The optimal cutoff of ADC values to differentiate benign and malignant bone tumors was defined as the point at which the Youden index, the sum of sensitivity and specificity, was maximized.

Results: The median values of the ADCmean, ADCmin, and ADCmax for benign bone tumors [1.34 (1.13-1.83), 0.98 (0.73-1.34), and 1.80 (1.57-2.46) × 10^-3mm²/s, respectively] were significantly higher compared to malignant bone tumors [0.93 (0.78-1.03), 0.59 (0.43-0.72), and 1.35 (1.22-1.66) × 10^-3mm²/s, respectively; all p < 0.05]. ADCmean yielded the highest diagnostic accuracy, with an optimal cutoff of 1.04 (0.94-1.15) × 10^-3mm²/s (sensitivity 77%, specificity 93%, AUC = 0.91). An ADCmin cutoff of 0.82 (0.65-0.98) × 10^-3mm²/s resulted in a sensitivity of 87.5%, specificity of 70.0%, and AUC of 0.85. An ADCmax cutoff of 1.48 (1.18-1.78) × 10^-3mm²/s achieved a sensitivity of 68%, specificity of 81%, and AUC of 0.80.

Conclusion: ADCmean, ADCmin, and ADCmax differ significantly between benign and malignant pediatric bone tumors, and the ADCmean provides the highest diagnostic accuracy.

Objective: Sciatic nerve injury is a rare, devastating complication of acetabular fracture.

Purpose: assess CT predictive value (bony features and perineural hematoma) for sciatic nerve injury following acetabular fracture.

Materials and methods: IRB-approved retrospective study (n = 471) from 2011 to 2022. Single rater evaluated each case for Judet-Letournel subtype, joint congruence loss, and posterior displacement. Three raters assessed perineural hematoma in zones 1-3: obturator internus, piriformis, and posterior thigh. EMG/NCS confirmed sciatic injury in 20 cases. Sensitivity, specificity, PPV, NPV, OR, and accuracy (AUC) were computed for each marker. Intra- and inter-rater reliability was calculated.

Results: Sciatic injury was most frequent in associated both column (8.0%) and transverse family (5.9%) fractures. Sensitivity and specificity of fracture features on sciatic injury were both column involvement (0.85 [17/20], 0.31 [140/451]), congruence loss (0.90 [18/20], 0.36 [163/451]), and posterior displacement (0.70 [14/20], 0.54 [244/451]). Joint congruence loss (OR 5.08, p = 0.016) and posteriorly displaced fragment (OR = 2.74, p = 0.04) were statistically significant (p < 0.05). For hematoma, sensitivity and specificity were zone 1, 0.65-0.80 [13/20-16/20] and 0.30-0.36 [136/451-161/451]; zone 2, 0.60-0.80 [12/20-16/20] and 0.39-0.57 [176/451-255/451]; and zone 3, 0.15-0.25 [3/20-5/20] and 0.69-0.86 [312/451-388/451]. AUC values were zone 1, 0.65-0.71 (satisfactory-to-good); zone 2, 0.69-0.71; and zone 3, 0.48-0.61 (poor-to-satisfactory). Values were significant in zones 1 and 2. Intra-rater reliability (Gwet's AC2) was almost perfect in zone 1 (0.86-0.87), moderate to almost perfect in zones 2-3 (0.47-0.90). Inter-rater agreement (Gwet's AC2) in zones 1-3 was 0.73 (substantial), 0.49 (moderate), and 0.50.

Conclusion: We found three statistically significant predictors of sciatic nerve injury following acetabular fracture: joint congruence loss, posteriorly displaced bone fragment, and perineural hematoma at the level of (a) obturator internus and (b) piriformis. Rater agreement for perineural hematoma was excellent for zone 1.

Objective: Percutaneous ultrasound-guided fenestration of ganglia (PUGG) in children has been a first line treatment option at our institution in lieu of surgical resection. The purpose of our study is to report our efficacy and safety of PUGG in symptomatic pediatric wrist ganglia, and to determine if any pre-procedural ultrasound findings help predict ganglia recurrence.

Materials and methods: A retrospective study of children who underwent PUGG of the wrist from May 2023 through November 2024 at an academic children's hospital was performed. Patients were excluded if the ganglion was ruptured on pre-PUGG imaging and were $\ge$ 19 years old. Patient demographics, pre-procedure ultrasound characteristics, procedure details, and recurrence/complications were collected by utilizing the electronic medical record and PACS. Continuous and categorical data were assessed with a significance level set to 0.05.

Results: There were 105 children (mean age (years):14.1 + / - 3.0 (4-18)) who underwent successful PUGG with 97.1% performed without sedation. Of these, 70 patients had optional clinical follow-up. Recurrence for the total population was 26.7% (28/105), and subset analysis for those patients with optional clinical follow-up was 40.0% (28/70). Ganglion symptom duration, ganglion size, presence of septations, internal debris, PUGG needle size, and steroid dosage did not statistically predict recurrence. Temporary numbness (2.9%) and site pain (7.6%) were the most common complications, and no children reported cosmetic scarring of the wrist.

Conclusion: PUGG is a safe, minimally invasive procedure to treat symptomatic pediatric wrist ganglia. With appropriate patient selection, PUGG can serve as a valuable first-line elective therapeutic treatment for wrist ganglia.

Objectives: To review MRI features of the axillary nerve in patients with clinical or MRI findings of axillary nerve dysfunction following glenohumeral dislocation and evaluate whether any MRI changes correlate with clinical axillary nerve function in follow-up.

Methods: Retrospective observational cohort study of MRIs in patients with axillary nerve dysfunction following shoulder dislocation. MRIs assessed by two observers independently, using inter-class correlation Cohen's kappa analysis, for denervation edema (deltoid, teres minor), T2-signal, caliber changes, discontinuity, perineural edema, and anatomic site of axillary nerve changes. Demographics, clinical, and electromyography results are documented. MRI findings assessed for correlation to nerve function 6 months post-dislocation.

Results: Thirty-seven patients (27 male, age range 17-71 years).years). The mean time interval from dislocation to MRI is 131 days. MRI findings are as follows: denervation edema (34/37), and increased T2-signal, caliber changes, disruption, or perineural edema (29/37). Nerve changes were most frequently observed anterior to the subscapularis or within the quadrilateral space. This later finding showed a significant association (p = 0.039) with non-improvement in nerve function. Twelve patients without clinically recognized axillary nerve dysfunction demonstrated MRI features of nerve injury (denervation edema 11/12, nerve changes 7/12). Twenty patients with clinically documented axillary nerve dysfunction demonstrated temporal recovery, while 5 showed no improvement 6 months post-dislocation.

Conclusions: MRI changes of denervation edema and nerve increased T2-signal and thickening are common findings in patients with axillary nerve dysfunction following shoulder dislocation. Although limited by small numbers, a correlation was observed between axillary nerve changes within the quadrilateral space and nerve dysfunction 6 months post-injury.

Organizing thrombus is a well described histologic finding involving the reorganizing and recanalization of a healing thrombus. However, it is rarely large enough to be described on imaging. When the thrombus becomes sufficiently large, intravascular papillary endothelial hyperplasia (IPEH) must be considered. IPEH or Masson's tumor is a benign, exuberant form of organizing thrombus that typically occurs in the soft tissues of the head, neck, and distal extremities. It can occur within a vessel, hematoma, or vascular mass and can mimic benign processes or malignant lesions such as angiosarcoma. Histopathological characteristics are needed for final diagnosis. The treatment is typically complete surgical resection with excellent prognosis. We report the case of a patient presenting with swelling in his left forearm in the same site as a previously treated left basilic vein thrombus. Ultrasound demonstrated a noncompressible, heterogeneous intravascular mass with internal vascularity. Subsequent MRI showed an enhancing mass centered in the left basilic vein with a flow void with the differential diagnosis of IPEH versus intravascular neoplasm. Percutaneous biopsy was performed with histology consistent with reactive vascular proliferation and organizing thrombus. The papillary architecture diagnostic of IPEH was absent. Regardless of final specific terminology, this case presents exuberant organizing thrombus as a benign cause of an enhancing intravascular mass. This patient was treated conservatively with no further intervention.

Epiphyseal and metaphyseal bone lesions in pediatric patients are uncommon, and lesions that cross an open physis are even rarer. The differential diagnosis for such lesions consists of infection, giant cell tumor, and chondroblastoma. We describe a 4-year-old male patient who presented with a bone tumor originating in the proximal tibial metaphysis that extended across the physis into the epiphysis. Sampling revealed a HMGA2::NCOR2 fusion associated with a recently described subset of giant cell-rich bone and soft tissue tumors. This case expands the differential diagnosis for cross-physeal and epiphyseal bone tumors in pediatric patients and highlights the radiological features of keratin-positive giant cell-rich tumor (KPGCT).

Nerve sheath myxoma (NSM) is a rare benign tumor originating from peripheral nerves. We present a case of NSM in the upper extremity. A 67-year-old female presented with painful nodular bulging in the elbow. Magnetic resonance imaging and ultrasonography revealed diagnostic features. Surgical excision was performed and histopathological examination confirmed the diagnosis. Our case contributes to the understanding of NSM's clinical presentation, imaging characteristics, and management strategies of NSM.