MEDLINE Abstracts: Imaging Modalities for the Assessment of Musculoskeletal Tumors

May 07, 2002

MEDLINE Abstracts: Imaging Modalities for the Assessment of Musculoskeletal Tumors

Kransdorf MJ
Orthopedics 17(11):1003-16, 1994 Nov

In summary, MRI is the preferred modality for the evaluation of a soft-tissue mass following radiography. The radiologic appearance of certain soft-tissue tumors or tumor-like processes such as benign fatty tumors, intramuscular hemangiomas, pigmented villonodular synovitis, and certain hematomas may be sufficiently unique to allow a strong presumptive radiologic diagnosis. It must be emphasized that MRI cannot reliably distinguish between benign and malignant lesions and, when radiologic evaluation is nonspecific, one is ill advised to suggest a lesion is benign or malignant solely on its MR appearance. The role of MRI in the evaluation of bone tumors is predominantly one of staging. MRI is superb to evaluate the extent of intraosseous and soft-tissue involvement as well as the relationship of the lesion to the neurovascular bundle. Unfortunately, MRI remains nonspecific and is unable to predict lesion histology. Finally, the value of Gd-DTPA enhanced imaging is still to be determined.

Thyagarajan D, Cascino T, Harms G
Neurology 45(3 Pt 1):421-7, 1995 Mar

We retrospectively reviewed the clinical records of all patients with cancer and brachial plexopathy who had an MRI of the brachial plexus between 1984 and 1993 (71 patients). The MRIs were reevaluated in a blinded fashion. The presence of a mass adjacent to the brachial plexus on MRI was highly predictive of tumor infiltration as determined by clinicopathologic criteria and was the most useful feature in distinguishing radiation plexopathy from tumor infiltration. Increased T2 signal in or near the brachial plexus was commonly seen in both groups and was not useful in this distinction. MRI was very sensitive for brachial plexus abnormalities in this condition, and limited comparison with CT suggested that MRI is superior to CT as an imaging modality. CT performed sufficiently well, however, to suggest that a prospective comparison study of the cost effectiveness and clinical utility of the two imaging modalities in this clinical setting is warranted.

Shankman S, Cisa J, Present D
Magnetic Resonance Imaging Clinics of North America 2(1):139-53, 1994
Feb

Although tumor and tumor-like conditions of the foot and ankle are unusual, certain bone and soft tissue lesions are more common than others. Conventional radiographs remain essential in all such cases and are especially specific for intraosseous tumors. MR imaging is more sensitive to the presence and extent of both bone and soft tissue lesions.

Kier R
Magnetic Resonance Imaging 11(2):149-62, 1993

Twenty-one patients were referred for MR imaging of mass lesions in the foot and ankle detected initially by either palpation (15 patients) or radiographs (6 patients). In 3 cases, MRI excluded a discrete mass. In the remaining 18 patients with confirmation of mass lesions, the combination of signal features and tumor location suggested a specific diagnosis in 11 patients (61%). In 4 other cases, correlation with radiographs suggested likely diagnoses. In 3 cases, the MRI appearance was nonspecific. We conclude that the combination of signal features and tumor location at MR imaging often permits characterization of tumors of the foot and ankle.

Mitchell M, Sartoris DJ
Journal of Foot & Ankle Surgery 32(3):311-42, 1993 May-Jun

The authors describe magnetic resonance imaging (MRI) of the foot and ankle using a variety of cases studied. This modality represents considerable benefit in dealing with the difficult pathologic conditions, as well as clarifying others that may not be evident on plain radiographs. The soft tissue versus osseous abnormalities may be differentiated on the T1 versus T2 images. An excellent pictorial review dealing with the foot and ankle is offered.

Kransdorf MJ, Meis JM
Radiographics 13(4):853-84, 1993 Jul

Extraskeletal osseous and cartilaginous tumors and tumorlike conditions of the extremities can often be differentiated radiologically; for those that cannot, knowledge of the spectrum of lesions will allow a suitably ordered differential diagnosis. Of the osseous lesions--myositis ossificans, fibro-osseous pseudotumor, fibrodysplasia ossificans progressiva, soft-tissue osteoma, and extraskeletal osteosarcoma--all but myositis ossificans are relatively rare. Myositis ossificans has a distinct mineralization pattern that can be observed radiologically as a peripheral rim of lamellar bone. Fibro-osseous pseudotumor typically occurs in the digits of the hand and lacks the well-defined zoning pattern of myositis ossificans. The cartilaginous entities include the true tumors, soft-tissue chondroma and extraskeletal chondrosarcoma, and the tumorlike process, synovial osteochondromatosis. The tumors are relatively rare; synovial osteochondromatosis commonly affects middle-aged men, especially in the knee, and is associated with osteoarthritis. The differential diagnosis for these extraskeletal osseous and cartilaginous lesions includes soft-tissue sarcoma, benign mesenchymoma, malignant mesenchymoma (rare), calcified tophi in gout, melorheostosis (rare), pilomatricoma (rare), and tumoral calcinosis (rare).

Schweitzer ME
Magnetic Resonance Quarterly 9(4):214-34, 1993 Dec

Magnetic resonance imaging (MRI) of the foot and ankle is useful for the diagnosis and staging as well as the surgical planning of multiple disorders: first, for osseous injury, particularly stress fractures and occult fractures, which appear like bone bruises but behave more like fractures. Then, for the Achilles tendon, MR is useful for staging the chronicity and extent of damage, as well as whether the tendon can be surgically repaired or reconstructed. For the diagnosis of posterior tibialis tendon tears and injuries, MR is an important tool in surgical planning. Often, MR is helpful for the diagnosis of peroneal tendon injury, including dislocations and peroneal splits, two entities that are seen to affect only the peroneal tendons. MR helps in the evaluation of avascular necrosis in any bone secondary to various systemic causes, particularly following talus fractures. MR has also been utilized to assess ankle sprains with complications, such as the ankle impingement syndrome, the sinus tarsi syndrome, and chronic instability, and to diagnose osteomyelitis (since the typical patient also has neuropathic disease bone, scintigraphy is invariably abnormal). MR is promising for the evaluation of reflex sympathetic dystrophy and is as useful for the evaluation of bone and soft tissue tumors as it is elsewhere in the skeleton. MR helps to characterize the biological aggressiveness of the tumor as well as its extent and therefore aids in surgical planning.

Terk MR, Gober JR, de Verdier H, Simon HE, Colletti PM
Magnetic Resonance Imaging 11(7):931-9, 1993

This study evaluated the use of the Spectral presaturation with inversion recovery (SPIR) technique with T2-weighting in 43 pathologically proven cases of suspected musculoskeletal neoplasm. Both primary and secondary malignant neoplasms as well as benign neoplasms were studied. The MR features exhibited by this technique are discussed. The images were evaluated by two experienced MRI specialists and graded as to utility into one of four categories as compared to conventional T1- and T2-weighted sequences. In the majority of cases this technique was found to be helpful or extremely helpful. The most useful features of this technique were the elimination of chemical shift artifact, the improved ability to evaluate superficial lesions or the extension of lesions into subcutaneous fat, and substantially improved visualization of both bone marrow and bone cortex interfaces. T2-weighted, fat suppressed imaging proved to be a useful new tool for evaluating musculoskeletal neoplasms.

Yu JS, Vitellas KM
Foot & Ankle International 17(12):771-80, 1996 Dec

The calcaneus is the largest bone in the foot and is an important primary weightbearing structure. Pathologic processes that affect this bone may manifest in a variety of clinical presentations, including pain, abnormal motion, instability, or fracture. The purpose of this article is to present a pictorial essay of the wide spectrum of pathologic entities that may affect the calcaneus, emphasizing applications of magnetic resonance imaging and characteristic magnetic resonance features of these processes.

Sonin AH, Tutton SM, Fitzgerald SW, Peduto AJ
Radiographics 16(6):1323-36, 1996 Nov

Magnetic resonance (MR) imaging can provide important diagnostic information in the evaluation of the adult elbow. Optimal imaging technique should include the use of proper positioning, surface coils, and appropriate sequences and imaging planes as indicated by the suspected abnormalities. A familiarity with the anatomy of the normal elbow is crucial to identifying pathologic entities correctly and avoiding diagnostic pitfalls. Disruption of the collateral ligaments can best be demonstrated with thin-section coronal gradient-echo MR images. Injuries to the flexor and extensor muscle groups, biceps muscles, and triceps muscles require T2-weighted or short-inversion-time inversion recovery (STIR) MR images in the long and short axes of the affected muscle. The evaluation of osteochondral lesions and intraarticular bodies is optimized with T1-weighted and STIR MR images. Synovial processes usually necessitate the intravenous administration of gadopentetate dimeglumine to distinguish joint fluid from pannus. The contents of the cubital tunnel are best visualized on axial T1-weighted and STIR MR images. Masses arising in or near the elbow should be imaged with multiple sequences in at least two planes, and involvement of adjacent vital structures should be carefully evaluated.

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