The role of diskography after negative postmyelography CT scans: retrospective review.

Review of our records for a 2-year period (1985-1986) yielded 15 patients in whom unequivocally normal myelograms and postmetrizamide CT scans had been obtained before diskography. In none of these patients was the diskogram or postdiskography CT scan positive for either central, posterolateral, or extreme lateral disk herniation. It was our experience that, with the new-generation, improved-resolution CT scanners with multiplanar reconstruction capabilities, diskography added no additional information, did not influence the surgeon's decision to operate, and was not a painless or innocuous procedure. When an entirely negative, technically flawless postcontrast CT scan is obtained in a patient with back pain, diskography should not be performed, as it offers no further information.

Bilateral calcaneal intraosseous lipomas: a case report.

A case of bilateral intraosseous calcaneal lipomas in a 40-year-old man is presented. Because of the benignancy and the virtually diagnostic appearance of this lesion radiographically, a bone biopsy was not performed. This may be the first case of bilateral involvement of the calcaneous by intraosseous lipomas.

Intramuscular myxoma: magnetic resonance features.

Magnetic resonance imaging (MRI) was performed in six cases of intramuscular myxoma of the extremities and revealed the following characteristics. All tumours were confined to muscle and had a sharply defined border. All had a signal intensity lower than skeletal muscles on T1-weighted images and brighter than fat on T2-weighted images. The signals were homogeneous on both T1- and T2-weighted images. This study did not include contrast enhancement. The diagnosis was confirmed by an open biopsy. All tumours were resected with no recurrence. Diagnosis based on these MRI characteristics was incorrect in two cases of intramuscular ganglia and in a case of intramuscular cysticercus cellulose. MRI features of intramuscular myxoma are typical in the majority of cases. Benign intramuscular lesions that contain mainly fluid can mimic intramuscular myxomas.

Tumour and tumour-like conditions of the soft tissue: magnetic resonance imaging features differentiating benign from malignant masses.

49 primary soft-tissue masses were studied by magnetic resonance imaging (MRI) in an effort to differentiate benign from malignant lesions. There were 24 benign and 25 malignant tumours. Images were evaluated for the presence of low-signal septation, changes in pattern of homogeneity, signal intensity, and margin definition and shape. 20 of the 25 malignant tumours (80%) demonstrated low-signal septation, and two of the 24 benign tumours (8%) also demonstrated this feature. Malignant tumours tended to change pattern from being homogeneous on T1-weighted images to being heterogeneous on T2-weighted images (72%). Benign tumours maintained their pattern on both sequences (67%). Only three of the 24 benign tumours (12.5%) changed from being homogeneous to heterogeneous. Our findings suggest that tumours which change pattern, from homogeneous on T1-weighted images to heterogeneous on T2-weighted images, and tumours which have low-signal septations are likely to be malignant. Moreover benign lesions tend to have well defined margins, and some benign masses have characteristic appearances that aid in their differentiation from malignant processes.

Osteoid osteoma of a cervical vertebral body.

An osteoid osteoma in the anterior part of the body of the fourth cervical vertebra occurred in a 22-year-old female. The patient's main complaint was neck pain and occasional numbness of the extremities. The pain was relieved by analgesics. Plain radiography and a 99Tcm MDP bone scan showed a non-specific abnormality. CT suggested the pathological diagnosis with reasonable certainty. The unusual location of the lesion and the role of various diagnostic modalities are discussed and the literature reviewed.

Subperiosteal giant-cell reparative granuloma.

We present a case of subperiosteal giant-cell reparative granuloma followed over six years showing the complete evolution from the early phase of subperiosteal haematoma to the end stage of an ossified haematoma. Such lesions, although they are histologically similar to true giant-cell tumours, can be distinguished by the patients' age, their location on the diaphysis, and by their radiological and histological features.

Osteoblastoma of the humerus associated with type-I Gaucher's disease. A case report.

We report a unique case of juxtacortical osteoblastoma of the humeral shaft, which stimulated the appearance of an extraosseous extension of Gaucher-cell deposits. The tumour was treated successfully by curettage and bone grafting. We can find no previous report of this association between osteoblastoma and Gaucher's disease.

A case report of anomalous branching of the popliteal artery.

A rare developmental anomaly of absent posterior tibial artery and hypoplastic anterior tibial artery is presented. In this case, marked hypertrophy of the peroneal artery compensated for the absent arteries. The peroneal artery also gave collaterals to form the dorsalis pedis and the plantar arteries.

Fractures of the sesamoid bone of the thumb.

Fracture of thumb sesamoids is a rare injury. We are reporting four cases. In two cases, the fracture involved the ulnar sesamoid and in two others, the radial sesamoid. The right thumb was affected in two patients and the left thumb in the other two. In one patient, arthrography of the metacarpophalangeal joint of the thumb demonstrated contrast leakage from the volar aspect of the joint and confirmed volar plate rupture. All patients were treated conservatively with immobilization. Normal hand function was restored in all four patients. Sesamoid fractures may accompany severe injuries of the fibrous plate. Radiologists and orthopaedists should be aware of the possibility of this fracture in injuries of the thumb. Early recognition of the fracture leads to appropriate treatment and avoids possible instability of the metacarpophalangeal joint.

Eosinophilic granuloma of the left ischium.

A case of eosinophilic granuloma in an unusual location (ischium) is presented. Eosinophilic granuloma, a benign lesion of bone, has many radiographic appearances that vary with location. The flat bone of the skull and pelvis are common sites of involvement. Although the iliac wings and pubic rami are not uncommon sites for such a lesion, the ischium is a rare site. This occurrence prompted us to report this case.

Simple bone cysts: true recurrence after complete obliteration.

A report of recurrent simple bone cysts in two cases--a seven-year-old and a six-year-old male--is presented. In each case curettage and cortical banked bone graft were performed. On follow-up, there was no clinical or radiographic evidence of further recurrence.

Intramuscular myxoma of the left forearm.

Intramuscular myxoma is a distinct benign tumor confined to muscles. This tumor usually favors the thigh and shoulder. We are reporting a case of intramuscular myxoma of the forearm in an elderly female, a very rare site for this tumor. The magnetic resonance features of intramuscular myxoma are described. The differential diagnosis that included acute hematoma, acute abscess, intramuscular synovial cyst, schwannoma and malignant soft tissue tumors with myxomatous degeneration is discussed. The association between intramuscular myxomas and fibrous dysplasia has been emphasized.