Skeletal Radiology最新文献

Aseptic abscess (AA) is a rare autoinflammatory disorder, characterized by the formation of sterile abscesses in various organs, and is accompanied by inflammatory bowel disease. Antibiotic treatment is ineffective, but steroid therapy shows a good response. AA can be difficult to differentiate from infection because abscesses appear similar both radiologically and histopathologically. Herein, we present the case of a 56-year-old woman with AA in the anterior chest wall and synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome.

Botryomycosis is a rare granulomatous response to chronic bacterial infection most frequently associated with Staphylococcus aureus. This disease, which predominantly affects immunocompromised patients, may present with cutaneous, visceral, or soft tissue manifestations. Soft tissue involvement typically has an aggressive mass-like appearance on imaging which can be concerning for malignancy. In immunocompromised patients, botryomycosis can resemble fungal infection both clinically and histologically; therefore, definitive diagnosis requires tissue sampling along with histological and microbiological analysis. Presented here is a 25-year-old man with an enlarging intramuscular soft tissue mass of the right forearm as his first presentation of undiagnosed acquired immunodeficiency syndrome (AIDS). MR imaging showed a mildly T2 hyperintense and enhancing mass with infiltrative margins extending through tissue planes. Biopsy of the mass revealed Staphylococcus aureus-associated botryomycosis, which improved with nonsurgical treatment employing antibiotics. Unfortunately, the patient subsequently expired from other manifestations of his new AIDS diagnosis. This case describes the MR and PET-CT appearance of botryomycosis and also underscores that infection can mimic sarcoma, particularly in the setting of immunodeficiency.

Imaging plays an important role in the workup of musculoskeletal infection, in conjunction with clinical history and physical exam. There are multiple imaging modalities that can be of clinical utility in the setting of suspected infection, each with their own benefits and limitations. Radiography is a low-cost, accessible modality providing a broad osseous overview, but can be insensitive for early osteomyelitis. Ultrasound plays a more limited role in the workup of musculoskeletal infection, but can be useful in the pediatric population or for real-time guidance for joint and soft tissue aspirations. Computed tomography (CT) plays an important role in the timely and accurate diagnosis of critically ill patients in the emergency setting. Its superior soft tissue characterization allows for diagnosis of abscesses, and it can help confirm the clinical diagnosis of necrotizing fasciitis when soft tissue gas is present. Magnetic resonance imaging (MRI) is often the modality of choice in the diagnosis of infection, as its superior contrast resolution allows for clear delineation of the presence and extent of both soft tissue infection and osteomyelitis. Additionally, the use of intravenous contrast and advanced imaging sequences such as diffusion weighted imaging (DWI) further increases the diagnostic utility of MRI in the assessment for infection. Familiarity with the diagnostic utility of each imaging modality will allow the radiologist to appropriately guide imaging workup in the setting of clinically suspected infection.

In modern practice, imaging plays an integral role in the diagnosis, evaluation of extent, and treatment planning for lower extremity infections. This review will illustrate the relevant compartment anatomy of the lower extremities and highlight the role of plain radiographs, CT, US, MRI, and nuclear medicine in the diagnostic workup. The imaging features of cellulitis, abscess and phlegmon, necrotizing soft tissue infection, pyomyositis, infectious tenosynovitis, septic arthritis, and osteomyelitis are reviewed. Differentiating features from noninfectious causes of swelling and edema are discussed.

Along with clinical and laboratory findings, imaging has a significant role in the initial evaluation and treatment follow-up of a wide variety of infectious and non-infectious musculoskeletal (MSK) conditions. The imaging findings of many non-infectious MSK processes, such as inflammatory, metabolic, and degenerative arthropathies, complications of diabetes mellitus, osseous and soft tissue injuries, osteonecrosis, tumors, and tumor-like lesions may be nonspecific and often overlap with those found in MSK infections. In this article, the authors discuss the imaging findings of both frequent and rare mimickers of MSK infections, including potential distinguishing characteristics.

Upper extremity infections are frequently seen, especially in individuals with weakened immune system, posttraumatic events, and after surgery procedures. If not properly treated, such conditions can lead to serious consequences, such as movement impairment, amputation, and even mortality. These infections have the potential to spread extensively from their initial site of entry, traversing interconnected spaces either intra or extra-compartmental. Understanding the relevant anatomy is crucial to assess location and stage of infection, since surgical intervention and intravenous antibiotics are usually required. In this article, the authors provide a comprehensive review of the imaging findings of upper extremity infection, focusing on magnetic resonance imaging (MRI). Furthermore, this article sheds light on the pivotal role of radiology in managing hand, elbow, and shoulder infections offering an overview of available treatment options. KEY FINDINGS: Various types of infections affecting the upper extremity will be discussed, including infectious tenosynovitis, deep space infections, septic arthritis, and osteomyelitis. Authors also highlight anatomical spaces, common pathogens, spread routes, and key radiological features of these conditions.

Musculoskeletal infections in the ER are not an uncommon presentation. The clinical context is critical in determining the suspicion for infection and degree of tissue involvement which can involve all layers from the skin to bones. The location, extent, and severity of clinically suspected infection directly relate to the type of imaging performed. Uncomplicated cellulitis typically does not require any imaging. Localized and superficial infections can mostly be evaluated with ultrasound. If there is a diffuse site (an entire extremity) or suspected deeper involvement (muscle/deep fascia), then CT is accurate in diagnosing, widely available, and performed quickly. With potential osseous involvement, MRI is the gold standard for diagnosing acute osteomyelitis; however, it has the drawbacks of longer scan times, artifacts including patient motion, and limited availability.

Objectives: To retrospectively evaluate the correlation between intradiscal gas and infection in patients percutaneously biopsied for suspected discitis-osteomyelitis.

Materials and methods: We retrospectively reviewed all CT-guided discitis-osteomyelitis biopsies performed between 2002 and 2022. Two independent trained musculoskeletal radiologists evaluated for presence of gas on CT and/or MRI within 1 week of the biopsy. Disagreements were resolved by a third musculoskeletal radiologist. CT was considered the gold standard for the detection of intradiscal gas. Pathology, microbiology, and imaging and clinical follow-up were used as the gold standard for presence of infection. Interrater agreement on CT and MRI, sensitivity, and positive predictive value were calculated, using the presence of gas as an indicator (test positive) for "no infection."

Results: There were 284 biopsies in 275 subjects (mean age 58 ± 1.0 (range 4-99) years; 101 (37%) females and 174 (63%) males). Of the biopsies, 12 (4%) were cervical, 80 (28%) were thoracic, 192 (68%) were lumbar, and 200 (70%) were considered true discitis-osteomyelitis based on pathology, imaging, and clinical follow-up. Interrater agreement was excellent for CT (kappa = 0.83) and poor for MRI (kappa =  - 0.021). The presence of gas had a 94% specificity and 76% negative predictive value for the absence of infection.

Conclusion: CT is the preferred method for detecting intradiscal gas. The presence of gas means that discitis-osteomyelitis is unlikely. If intradiscal gas is present in the setting of discitis-osteomyelitis, the gas bubbles tend to be smaller and fewer in number.

Tuberculosis (TB) represents a major public health problem worldwide. Any tissue may be infected. Involvement of the musculoskeletal (MSK) system account for 1-3% of all tuberculous infections. MSK TB may manifest as tuberculous spondylitis, arthritis, osteomyelitis, and soft tissue infections. Although TB spondylitis may present with distinctive imaging features compared to pyogenic infections of the spine, the imaging semiology of extra-spinal TB infections is mostly nonspecific and may mimic other lesions. TB infections should therefore always be considered in the differential diagnosis, particularly in immunocompromised patients. The aim of this article is to review the imaging features of spinal and extra-spinal MSK TB. Magnetic resonance imaging is considered the modality of choice to make the diagnosis and to evaluate the extent of the disease.