Skeletal Radiology最新文献

Objective: Prostate-specific membrane antigen (PSMA)-PET/CT has shown considerable promise in the evaluation of prostate cancer bone metastases; however, data utilizing a histopathologic reference standard in this setting are limited. We therefore sought to evaluate the diagnostic performance of PSMA-PET/CT using a consistent histopathologic gold standard in the form of bone biopsy.

Materials and methods: In this single-center, retrospective study, we identified 80 patients with prostate cancer who underwent CT-guided bone biopsy of a tracer-avid osseous lesion on PSMA-PET/CT performed with ¹⁸F-piflufolastat. Concordance between PET/CT and histopathology and the positive predictive value of PSMA-PET/CT were determined. Factors predictive of positive biopsies were also evaluated.

Results: PSMA-PET/CT and bone biopsy results were concordant in 55/80 patients (69%), and the positive predictive value of PSMA-PET/CT for osseous metastasis of prostate cancer was 66% (53/80). Positive predictive values for spine, pelvis, and rib biopsies were 82% (23/28), 72% (18/25), and 26% (5/19), respectively. Peak SUV and its ratio to liver mean SUV were significantly higher in biopsy-positive lesions compared to biopsy-negative lesions. A threshold peak SUV to liver mean SUV ratio of 1.7 had a sensitivity of 61% and a specificity of 92% for a histopathologic diagnosis of metastatic prostate cancer.

Conclusion: PSMA-PET/CT has a moderately high histopathologic concordance and positive predictive value for the diagnosis of osseous metastatic disease in prostate cancer. Peak SUV is useful for distinguishing biopsy-positive from biopsy-negative lesions. In keeping with prior investigations, a majority of biopsied rib lesions were negative for metastatic prostate cancer.

Objective: To determine the accuracy of automatic Cobb angle measurements by deep learning (DL) on full spine radiographs.

Materials and methods: Full spine radiographs of patients aged > 2 years were screened using the radiology reports to identify radiographs for performing Cobb angle measurements. Two senior musculoskeletal radiologists and one senior orthopedic surgeon independently annotated Cobb angles exceeding 7° indicating the angle location as either proximal thoracic (apices between T3 and T5), main thoracic (apices between T6 and T11), or thoraco-lumbar (apices between T12 and L4). If at least two readers agreed on the number of angles, location of the angles, and difference between comparable angles was < 8°, then the ground truth was defined as the mean of their measurements. Otherwise, the radiographs were reviewed by the three annotators in consensus. The DL software (BoneMetrics, Gleamer) was evaluated against the manual annotation in terms of mean absolute error (MAE).

Results: A total of 345 patients were included in the study (age 33 ± 24 years, 221 women): 179 pediatric patients (< 22 years old) and 166 adult patients (22 to 85 years old). Fifty-three cases were reviewed in consensus. The MAE of the DL algorithm for the main curvature was 2.6° (95% CI [2.0; 3.3]). For the subgroup of pediatric patients, the MAE was 1.9° (95% CI [1.6; 2.2]) versus 3.3° (95% CI [2.2; 4.8]) for adults.

Conclusion: The DL algorithm predicted the Cobb angle of scoliotic patients with high accuracy.

Gout is a common and growing health concern globally, marked by the deposition of monosodium urate (MSU) crystals in joints and soft tissues. While diagnosis relies on synovial fluid analysis, it is limited by technical difficulties and a notable rate of false negatives. Over the past decade, dual-energy computed tomography (DECT) has emerged as a highly sensitive and less-invasive modality for detecting MSU crystals. DECT offers several advantages, including the ability to visualize both intra- and extra-articular MSU deposits and to monitor crystal burden over time. It also aids in treatment planning by accurately assessing the therapeutic response. However, sensitivity of DECT can be lower in early-stage gout, and artifacts can occasionally result in false positives. Recent studies have highlighted new values of using DECT, such as predicting future flares in gout patients. In this review, we focus on the comprehensive clinical utility of DECT and its potential pitfalls in the diagnosis and management of gout.

We present a case of biopsy-proven epithelioid angiosarcoma in an arteriovenous fistula (AVF). Angiosarcomas developing in non-functioning AVF in renal transplant recipients are rare clinical entities with poor prognosis. A 59-year-old male adequately immunosuppressed kidney transplant patient presented with pain and swelling at the site of a previously asymptomatic fistula. A duplex scan confirmed the presence of thrombosis present along the length of the AVF; however, in light of worsening pain and skin changes, an MRI scan was requested. This demonstrated a thrombosed brachiocephalic AVF and a more sinister appearing irregular segment infiltrating the underlying anterior compartment musculature with associated muscle oedema and internal irregular enhancement. A staging CT thorax showed indeterminate lymphadenopathy in the left axilla with no pulmonary lesions. Core needle biopsy of the primary lesion at the fistula site and subsequent biopsy of the axillary lymph nodes revealed metastatic angiosarcoma. A multidisciplinary decision was made to perform radical surgery with above-elbow amputation and simultaneous left axillary lymph node clearance. We focus on relevant imaging findings to facilitate early recognition of angiosarcoma, in particular, the importance of requesting urgent imaging of vascular access sites (functioning or not) in post-transplant patients presenting with swelling. Although rare, angiosarcoma is an important entity that should be considered in the differential diagnosis of soft tissue masses arising from a vascular access, especially in immunocompromised patients.

Objectives: To assess calf muscle constitution in chronic Achilles tendon disease (ATD) using two-point Dixon-based MRI (2pt-MRI_DIXON).

Materials and methods: This retrospective study analyzed 91 patients (36 females; 57.0 ± 14.4 years) with midportion or insertional chronic ATD who underwent clinical MRI of the Achilles tendon (AT), including 2pt-MRI_DIXON for quantitative assessment of calf muscle fat content (MFC). Additionally, two radiologists qualitatively assessed MFC, AT quality, and co-pathologies. 2pt-MRI_DIXON-derived fat fractions (FF) were related to patients' demographics and qualitative imaging findings.

Results: The overall mean FF derived from 2pt-MRI_DIXON of the triceps surae muscle was 11.2 ± 9.3%. Comparing midportion and insertional ATD, there was no significant difference regarding fatty muscle infiltration assessed with 2pt-MRI_DIXON (P ≥ .47) or qualitative grading (P ≥ .059). More severe AT thickening (11 vs.9 mm, P < .001) and complete tears (29 vs. 9%, P = .025) were significantly more common in midportion ATD, while partial tears were significantly more frequent in insertional ATD (55 vs. 31%, P = .027). Soleus muscle edema was more prevalent in midportion than insertional ATD (40 vs. 9%, P = .002). In contrast, insertional ATD more commonly featured bone marrow edema (61 vs. 2%), Haglund's deformity (67 vs. 0%), and retrocalcaneal bursitis (82 vs. 43%) (P ≤ .002). Significant correlations (P ≤ .001) were demonstrated between FF, AT diameter, age (both in midportion and insertional ATD), and body mass index (in midportion ATD only) (ρ range = 0.53-0.61).

Conclusion: In chronic ATD, calf MFC was statistically equivalent (approximately 11%), irrespective of the localization of tendon damage. More severe tendon thickening and complete tears were more common in midportion ATD, and, vice versa, partial AT tears were significantly more frequent in insertional ATD.

Antihistamines, such as diphenhydramine, are active ingredients of a wide variety of antiallergics, sedatives, and sleep preparations and are often abused for purposes of euphoric effects or suicidal attempts. Antihistaminic overdose presents with symptoms of increased anticholinergic activity including urinary retention, mydriasis, and dry mucous membranes. However, antihistamine-induced rhabdomyolysis is a rare condition that presents with widespread skeletal muscle breakdown and release of metabolites into the circulation, resulting in myalgias and acute kidney injury. In this article, we report a rare case of rhabdomyolysis following the ingestion of a large quantity of diphenhydramine for a suicide attempt, who also presented with significantly elevated creatine kinase and acute renal injury. To our knowledge, this is the first case report of diphenhydramine rhabdomyolysis with MRI findings' correlation.

Objective: To describe the clinical presentations and radiological manifestations of Erdheim-Chester disease (ECD) in the extremities, with particular emphasis on radiologic findings, as radiographs are typically the initial imaging modality used in clinical practice.

Methods: Following the PRISMA guidelines, a comprehensive systematic search was performed across Scopus, PubMed, Web of Science, and Embase databases, covering case reports from inception until August 1, 2024. Included were studies with pathologically confirmed ECD (CD68 positive and CD1a negative) that were evaluated with at least one imaging modality and provided detailed descriptions of radiological findings.

Results: Out of 401 identified articles, 20 articles comprising 20 histologically confirmed cases of ECD met the inclusion criteria following screening and full-text review. Pathological reports were assessed for the presence of lipid-laden cells and Touton giant cells, which were identified in 84.2% and 75% of cases, respectively. Upper extremities were affected in 65% of cases and lower extremities in all cases. Symmetric involvement was observed in 84.6% of upper extremity cases and 84.2% of lower extremity cases. Radiological findings were categorized as pure sclerosis (53.3%) and cortical thickening (42.8%) identified as the most common findings. Clinical manifestations were assessed, with pain and swelling in the extremities being the most common symptoms, occurring in 70% of cases.

Conclusion: The hallmark of ECD is bilateral, symmetric diaphyseal and/or metaphyseal osteosclerosis in the long tubular bones of the lower extremities. Epiphyseal sparing is observed in more than half of the patients.

Objective: MRI of the hands is valuable for risk-stratification in patients with arthralgia at-risk for developing rheumatoid arthritis (RA). Contrast-enhanced MRI is considered standard for assessment of RA, but has practical disadvantages. It also shows inflammation-like features in the general population, especially at older age, which should be considered in image interpretation. The modified-Dixon (mDixon) technique is reliable compared to contrast-enhanced sequences. Moreover, this short protocol without contrast-enhancement is patient-friendly. Whether it also shows inflammation-like features in the general population is unknown. We studied this to support accurate use in the clinic.

Methods: Two hundred twenty symptom-free volunteers from different age-categories were recruited from the general population and underwent mDixon MRI of both hands. Two readers independently scored MRIs for synovitis, tenosynovitis, and bone marrow edema (BME) in the metacarpophalangeal-joints (MCP) and wrists according to the RAMRIS. Features were considered present if scored by both readers; frequencies > 5% were considered relevant in terms of specificity and determined per age-category (< 40/40- < 60/ ≥ 60-years).

Results: Higher age correlated with higher BME-scores (p-value < 0.005), but not with synovitis and tenosynovitis-scores. BME (grade 1) occurred in some bones in people aged ≥ 60, 14% had BME in the lunate, 7% in metacarpal-1, and 6% in the trapezium. Synovitis and tenosynovitis did not occur in > 5%, except for grade-1 synovitis in the right distal radio-ulnar-joint in people aged ≥ 60 (11%).

Conclusion: On mDixon MRI, inflammatory features in the hands of the general population are rare. This facilitates image interpretation. To prevent overinterpretation, only several locations should be considered when evaluating people aged ≥ 60-years.

COL9A1 encodes the alpha-1 chain of type IX collagen heterotrimer, which is a vital component of collagen fibrils in hyaline cartilage. There are preliminary lines of evidence suggesting that COL9A1 mutations may be associated with autosomal dominant multiple epiphyseal dysplasia (MED), a disorder affecting the epiphysis of long bones. With only 2 reported cases (both from the same family) of MED in autosomal dominant COL9A1-related disorders (MIM 614135) in the clinical scientific literature hitherto, the phenotype is poorly understood at present. Here, we report the clinical and imaging findings associated with a novel COL9A1 mutation in comparison to the previously reported cases. We studied a 22-year-old male, who presented with a chronic history of leg pain and laxity of the knee joint, in the context of a history of pectus carinatum requiring a chest brace, and tall stature (height = 186.9 cm) with bilateral piezogenic pedal papules. Gene panel testing and a radiographic skeletal survey were subsequently performed. Gene panel test showed a heterozygous pathogenic variant in the COL9A1 that is denoted as c.188del (p.Phe63Serfs*3) and is predicted to result in a loss-of-function. The patient's long bones all appeared slender on a radiograph, without apparent epiphyseal dysplasia. Our findings suggest that the phenotypic spectrum of COL9A1-related disorders may potentially include other skeletal anomalies (such as pectus carinatum and slender appearance of long bones) aside from epiphyseal dysplasia.

Myopericytoma is a rare benign smooth-muscle cell neoplasm of the subcutaneous soft tissues that is primarily found in young adults with a male predominance. We present the clinical, radiologic, and histopathologic features of a longstanding myopericytoma of the hand. We emphasize the features that help the radiologist and pathologist to accurately characterize this entity. Radiologic evaluation, particularly MRI, plays a crucial role in differentiating myopericytoma from other soft tissue masses. Characteristic MR features include a well-demarcated lesion with intense post-contrast enhancement, isointensity to muscle on T1-weighted imaging, and hyperintensity on T2-weighted imaging, often with a central vascular pedicle. Histopathologic examination reveals a concentric perivascular growth pattern, which helps to distinguish myopericytoma from other soft tissue tumors. Immunohistochemically, these myoid cell neoplasms stain positive for alpha-smooth muscle actin and h-caldesmon, lack nuclear atypia, and are not highly proliferative (relatively low Ki-67 index and very low mitotic activity). The vast majority stain negative for desmin and CD34. Treatment typically involves complete surgical resection, with excellent prognosis and rare recurrence. Despite its rarity, awareness of this entity is important for clinicians who encounter soft tissue masses of the extremities.