1,722,181 research outputs found
Synovial cysts, ganglion cysts, and bursae
No full textThis chapter focuses on the classification and imaging of synovial cyst, ganglion cyst, and bursae. These lesions clinically present as a soft tissue mass and are often referred to the radiologist for further workup of a “soft tissue tumor.” They are however of nonneoplastic origin and have in most scenarios characteristic imaging features
Mimics of synovial tumors due to trauma and inflammation
No full textTraumatic and inflammatory joint alterations suspicious of synovial tumor form an extensive and inhomogeneous group. Located either intra-articularly or around the joint within bursae, these disorders are challenging to diagnose on clinical examination and often require further imaging. Acute or chronic synovial disease in a patient with a history of previous injury may be related to hemarthrosis, bursitis, fibrin clot formation, or ganglion cyst around the joint. Inflammatory background is related to different forms of arthritides, crystal deposition diseases affecting joints, and rheumatic complications of infectious diseases. This chapter aims to comment on the most common findings and differential diagnosis of traumatic and inflammatory lesions mimicking synovial tumors
History Page: Leaders in MSK Radiology Augusto Pellegrini, 1877-1958
No full textThis history page in the series "Leaders in MSK Radiology" is dedicated to the memory and achievements of the Italian surgeon Augusto Pellegrini, whose name is partially associated with the medical eponym Pellegrini-Stieda disease.status: Publishe
Diagnostic algorithm of synovial tumors and tumor-like conditions
No full textIn this chapter, a diagnostic algorithm and essential key points for the imaging workup of synovial tumors and tumor-like conditions are provided.
It should be emphasized that imaging findings should be interpreted in conjunction with relevant clinical and laboratory examination. The imaging algorithm of a joint lesion should start with a conventional radiograph to detect or exclude calcifications complemented. Doppler-ultrasound examination is useful to diagnose or rule out benign synovial lesions such as ganglion or synovial cysts or inflammatory or posttraumatic synovial lesions. Ultrasound is particularly helpful for superficially located cystic lesion. If the lesion is deeply located or has no definite benign characteristics on these imaging modalities or cannot be characterized as a pseudotumoral or inflammatory lesion, MRI is mandatory. If MRI findings are equivocal or suggestive of malignancy, (imaging-guided) biopsy and subsequent histopathological examination have to be performed in a tertiary referral center following multidisciplinary discussion
Magnetic resonance imaging of synovial tumor and tumorlike conditions
No full textDue to its unparalleled soft tissue resolution and multiplanar imaging capability, MRI is the modality of choice for imaging synovial tumor and tumorlike lesions. The minimal hardware requirements, imaging protocol, and either basic or advanced MR sequences are described. For lesion characterization, four major groups can be distinguished based on the analysis of signal intensities on T1- and T2-weighted images. Furthermore, this chapter gives an overview on the role of MRI in grading and local staging and might serve as a guideline for suggesting a relevant differential diagnosis and prognosticating the probability or degree of malignancy of synovial tumors. MRI characteristics for some specific tumors are further described in the respective chapters of this book
Synovial chondromatosis
No full textPrimary synovial chondromatosis (PSC) is a rare, benign neoplastic disorder affecting otherwise healthy joints. It is characterized by formation of cartilaginous nodules in the synovial lining. These nodules can detach from the synovium and evolve to numerous intra-articular loose bodies, which may be calcified or not. On conventional radiography, calcified nodules are readily visible in most cases but uncalcified nodules may remain unrecognized. MRI has a higher sensitivity for detecting uncalcified PSC but also for detecting bone erosions. In addition, MRI is the modality of choice to exclude bone marrow invasion, suggestive of a malignant lesion, which is extremely rare. On histopathology, PSC may show cytologic atypia, possibly making differentiation from low-grade synovial chondrosarcoma (SChS) difficult. Correlation of clinical, radiologic, and histologic findings is therefore pivotal to avoid misdiagnosis, which could lead to harmful treatment. The intra-articular bodies in secondary synovial chondromatosis (SCC) originate from detached cartilage secondary to nonneoplastic joint abnormalities such as degenerative joint disease, trauma, or other diseases causing cartilage damage. Histopathologic examination is able to differentiate primary and secondary forms in rare cases of nonspecific imaging features. This chapter focuses on the imaging features of PSC and SCC and its relevant differential diagnosis
Accessory muscles of the extremities
No full textAccessory muscles and variations are not uncommon at the upper and lower extremity. They are often overlooked because they are asymptomatic and present as incidental findings on imaging. However, they may present as a soft tissue swelling, thereby mimicking soft tissue tumors. Other symptoms are attributed to impingement on neurovascular structures and to exercise-related pain. Thorough knowledge of the anatomy, systematic imaging analysis, and the awareness of it are the clues to correct identification. On ultrasound, accessory muscles have a similar echotexture as other muscles, whereas the signal intensity on magnetic resonance imaging (MRI) is similar to muscle. Because of the intrinsic contrast with the adjacent intermuscular fat, accessory muscles are best depicted on MRI without fat suppression. This article provides a short overview of the anatomy of most prevalent accessory muscles of the upper and lower limb and its potential pathogenic nature
Plasmacytoma
No full textSolitary plasmacytoma of bone is one of many existing types of bone tumors
and is part of the plasma cell disorder spectrum. It is a local clonal plasma cell
proliferation without evidence of symptomatic multiple myeloma. It occurs
slightly more frequently in males with a median age at diagnosis of 55 years.
The thoracic vertebrae are most frequently involved. The exact etiology is
unknown, although a role for acquired B-cell defects is suggested. In children
and young adults, preceding trauma might play a role in the development of
solitary plasmacytoma of bone. Compared to extramedullary plasmacytoma,
solitary plasmacytoma of bone has a significantly worse prognosis, progressing
to symptomatic multiple myeloma in over 50% of cases. The survival rates are
significantly worse in case of abnormal serum immunoglobulin free light chain
ratio, in patients diagnosed after the age of 60 years and in female patients.
In one-third of presumed “solitary” plasmacytomas, an additional lesion is
characterized with subsequent diagnostic imaging, marking the importance
of further investigations when an apparent solitary plasmacytoma of bone is
encountered. Conventional radiography plays a distinct role in the imaging
and detection of solitary plasmacytoma of bone, mostly in the presence of
clear clinical symptoms. It may show a “punched-out” lesion appearance with
generally clear margins and normal surrounding bone. More advanced cases
may be paired with marked erosion and cortical bone destruction, creating a
“soap bubble” appearance. On CT, solitary plasmacytoma of bone presents
as a uni- or multilocular lesion, causing focal trabecular destruction. A
characteristic “mini brain” appearance may be observed. On conventional MRI,
plasmacytoma is iso- to hypointense on T1-weighted images and hyperintense
on (fat-saturated) T2-weighted images compared to muscle and enhances
homogeneously after gadolinium contrast administration. Specialized MRI
techniques such as dynamic contrast-enhanced MRI and diffusion-weighted
imaging also play an important role, especially in assessing disease extent and
differentiation with multiple myeloma, where a focal solitary plasmacytoma of
bone is accompanied by surrounding or distant bone marrow invasion. 18F-FDG
PET/CT is useful in the evaluation and has a prognostic value both at diagnosis
and in the evaluation of treatment
- …
