Skeletal Radiology最新文献

Objective: To analyze and quantify the change in United States of America Medicare reimbursement rates for the 30 most commonly performed spinal imaging procedures.

Materials and methods: The Physician Fee Schedule Look-Up Tool from the Centers for Medicare & Medicaid Services was utilized to find and extract the 28 most billed spinal imaging procedures. All data was adjusted for inflation and listed in 2020 US dollars. Percent change in reimbursement and Relative Value Units between 2005 and 2020, both unadjusted and adjusted, were calculated and compared. Additionally, percent change per year and compound annual growth rate were calculated and compared.

Results: After adjusting for inflation, the average reimbursement for all analyzed spinal imaging procedures between the years 2005 and 2020 decreased by 45.9%. The adjusted reimbursement rate for all procedures decreased at an average 4.3% per year and experienced an average compound annual growth rate (CAGR) of - 4.4%. Magnetic resonance imaging (MRI) had the most substantial adjusted decline of all imaging modalities at - 72.6%, whereas x-ray imaging had the smallest decline at - 27.33%. The average total RVUs per procedure decreased by 50.1%, from 7.96 to 3.97.

Conclusion: From the years 2005 to 2020, Medicare reimbursement significantly decreased for all advanced imaging modalities involving the most common spinal imaging procedures. Among all practices, imaging procedures may be experiencing some of the largest decreases from Medicare reimbursement cutbacks.

Objectives: Several studies have demonstrated the potential of tin-prefiltration to reduce radiation dose while maintaining diagnostic image quality for musculoskeletal imaging. Still, no study has reported data on the impact of tin-prefiltration on radiation dose reduction for clinical routine scanning.

Materials and methods: Retrospective inclusion of 300 clinically indicated CT scans of the pelvis, knee, and ankle before January 2020 (without tin filter) and after December 2020 (with tin filter). For each joint, 50 examinations with tin-prefiltration and 50 examinations without tin-prefiltration were selected. Dose parameters were extracted, calculated, and compared. Subjective and quantitative parameters for image quality were assessed.

Results: The CTDI_vol, DLP, and effective dose were reduced significantly in all tin-prefiltered examinations compared to the non-tin-prefiltered examinations (p < 0.001): CTDI_vol was 65% lower in the pelvis, 73% lower in the knee, and 54% lower in the ankle. This reduced the effective dose of 61%, 71%, and 60%, respectively. In absolute numbers, the reduction of the median effective dose delivered in a single CT scan of the pelvis was - 2.29 mSv, - 0.15 mSv for the knee, and - 0.03 mSv for the ankle. No difference in diagnostic image quality, depiction of bone anatomy and soft tissues, and image artifacts was observed (p > 0.05). Subjective and objective image noise was higher in tin-prefiltered pelvis CT (p < 0.001).

Conclusion: The implementation of tin-prefiltration in clinical routine scan protocols significantly reduced the effective radiation dose for unenhanced CT scans of the lower extremities between 60 and 70%.

A 50-year-old female presented with a large palpable mass in the right buttock and proximal thigh, accompanied by sciatic paresthesia. She reported intermittent thigh and knee pain for 5 years, worsening over the previous 6 months. Plain radiography images revealed a pedunculated osteochondroma on the posterolateral aspect of the femur with extensive soft tissue involvement and soft tissue calcifications. A computed tomography (CT) scan showed an osteochondroma with a large adjacent bursa containing multiple foci of calcifications with a "snowstorm" appearance. A diagnostic dilemma arose regarding whether the condition represented reactive bursitis secondary to osteochondroma or a malignant transformation to chondrosarcoma with intra-bursal invasion. Magnetic resonance imaging (MRI) indicated a thick cartilage cap of osteochondroma measuring 53 mm and multiple cartilage nodules in the bursa along with heterogeneous enhancement in cartilage islands. Moreover, evidence of adjacent muscle invasion and sciatic nerve encasement was noted. These findings suggested an unusual diagnosis of malignant transformation of the osteochondroma to chondrosarcoma with intra-bursal invasion. The patient underwent wide-margin resection of the proximal femur and tumoral soft tissue, reconstructed with a proximal femoral mega prosthesis. Histologic evaluation confirmed a well-differentiated chondrosarcoma with intra-bursal invasion. This case highlights the critical role of diagnostic imaging in differentiating between benign and malignant complications associated with osteochondroma.

Objective: To evaluate the diagnostic performance of 3D fast low-angle shot (FLASH) compared with conventional MRI sequences for detecting OPLL.

Materials and methods: This retrospective study included 106 patients who underwent cervical spine MRI and CT. Thirty-nine and 67 patients were enrolled in the OPLL and control groups, respectively. Diagnostic performance and reader confidence for detecting OPLL were compared between conventional MRI using turbo spin echo (TSE) and conventional MRI plus 3D FLASH. Interobserver agreement was also calculated. Three subgroups were defined within the OPLL group according to the sequences required for detecting OPLL (TSE group: cases that were diagnosed as OPLL by reviewing only TSE; 3D FLASH group: cases that were diagnosed by reviewing both TSE and 3D FLASH; none group: cases that were not diagnosed on MRI). The thickness of the OPLL was compared between the subgroups.

Results: The diagnostic performance of both readers improved when 3D FLASH was added to conventional MRI, and the difference was statistically significant for reader 2 (p = 0.006). After adding 3D FLASH, reader confidence significantly increased (p < 0.001), and interobserver agreement improved from good to excellent. The three subgroups exhibited significantly different OPLL thicknesses (p = 0.008), with the thickest in the TSE group (4.5 mm), followed by the 3D FLASH (3.4 mm) and None groups (2.4 mm).

Conclusion: 3D FLASH can be helpful for detecting OPLL when combined with conventional T1- and T2-weighted imaging.

Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease affecting nearly every organ system in the body. The musculoskeletal (MSK) system is frequently affected and often the earliest site of disease presentation. Tendon, tendon sheath, bone, muscle, and soft tissue involvement is assessed through a multimodality approach. Radiology has an evolving role in the diagnosis and management of SLE. In this article, the authors discuss the epidemiology, pathophysiology, and typical imaging findings, as well as review the role of imaging in the management of SLE.

Objective: To compare the magnitude of post-arthroplasty leg length discrepancy (LLD) and incidence of clinically significant LLD measured on CT scanogram using a commonly used measurement method (from the acetabular apex to tibial plafond) to an alternative technique avoiding the use of the acetabular prosthesis as a landmark and to assess inter-observer and intra-rater reliability of the new technique.

Materials and methods: In this retrospective study, post-arthroplasty LLD measurements were conducted in 100 hips by two interpreters on CT scanogram scout views from the acetabular apex to the tibial plafond (AA-TP) and the inter-teardrop line to the tibial plafond (IT-TP). Aggregate means and proportions of clinically relevant LLD (≥ 10 mm) were compared between methods. Inter-rater reliability was calculated, and both interpreters repeated measurements on ten randomly selected patients to calculate intra-rater reliability.

Results: The commonly used AA-TP technique overestimated LLD by 3.7 mm compared to the IT-TP technique. The odds of LLD measurement exceeding the clinically significant threshold of 10 mm were 3.8 times higher when using the AA-TP technique. Excellent inter-rater (ICC 0.984, 0.958) and intra-rater reliability (ICC > 0.9) were found for both techniques.

Conclusion: CT scanogram measurements from the acetabular apex to the tibial plafond often overestimate operative limb length due to reference landmarks in different axial planes. Measurements from the inter-teardrop line to the tibial plafond yield significantly lower LLD values, possibly reflecting actual limb length better. The authors recommend using the inter-teardrop line and tibial plafond as reference landmarks to improve LLD assessment accuracy post-arthroplasty.

Melorheostosis is a rare bone disease that presents as sclerotic lesions growing on existing bone surfaces. This disease is of unknown etiology and affects both genders equally. The disease is unique in appearance, described in the literature as having a radiologic appearance of flowing candle wax, and usually occurs in the appendicular skeleton. We present an extremely rare case of melorheostosis of the calvarium in a 55-year-old male patient, initially thought to represent a large osteoma, and discuss the CT and MRI features, pathology, and surgical management. Recently, new insights have been gained by molecular biologic studies into the potential pathogenesis of this disease indicating genetic mutations, which will be discussed. This case report will help radiologists arriving at the correct diagnosis for an unusual manifestation of a rare disease.