In vivo proton spectroscopy of giant cell tumor of the bone.

OBJECTIVE: The proton MR spectroscopic finding of elevated choline has been reported to be useful in the differentiation of malignant from benign musculoskeletal tumors. This study was designed to evaluate the MR spectroscopy features of giant cell tumor (GCT) of the bone, primarily to determine whether the presence of choline is a frequent occurrence in these tumors and whether MR spectroscopy features can be correlated with clinical, radiologic, and histopathologic findings. SUBJECTS AND METHODS: MRI, dynamic contrast-enhanced MRI, and proton MR spectroscopy were performed in 33 patients with bone tumors on a 1.5-T MR scanner. Of these, 12 patients who had GCT of the bone form the subject material for this study. Dynamic contrast-enhanced MRI and single-voxel proton MR spectroscopy were performed after preliminary evaluation with radiography. Patients were divided into two groups, those with elevated choline levels and those without a choline peak on MR spectroscopy. The clinical and radiologic features, including the Campanacci stage and dynamic MRI findings, were compared in these two groups. Core biopsy was performed in all patients, and in 10 of 12 patients, histopathologic evaluation of the postoperative resected specimen was also performed. RESULTS: Although all 12 tumors were benign on histopathology, four had elevated choline levels. Of these, three (75%) had an aggressive radiographic appearance (Campanacci stage 3). As opposed to this, only three of the eight (37.5%) tumors without a choline peak had an aggressive radiographic appearance. Except for a single case, all tumors showed early enhancement and washout of contrast material on dynamic MRI. CONCLUSION: The results of this study indicate that GCT of bone may show raised choline levels on proton MR spectroscopy. This finding is not an indicator of malignancy in these tumors.

Idiopathic bilateral acetabular labral ossification.

Acetabular labral ossification is an uncommon condition. We present a case of bilateral idiopathic acetabular labral ossification with no predisposing factor. The differential diagnosis of its plain radiographic appearance is discussed.

Extra-osseous fat fluid level: a specific sign for osteomyelitis.

Osteomyelitis may pose as a diagnostic dilemma on various imaging modalities and may be confused with neoplasms and other pathology. Although a rare finding, extra-osseous fat fluid level, especially when associated with spongy bone destruction, can be considered a specific sign of osteomyelitis. Previously, only two cases of extra-osseous fat fluid level in osteomyelitis have been reported, one on computed tomography (CT) and the other on magnetic resonance imaging (MRI). The former was a case of septic arthritis with intra-articular fat fluid level. A case of osteomyelitis is presented with the demonstration of extra-osseous fat fluid level. Our case is unique in providing exquisite CT and MRI correlation.

An unusual cause of intestinal obstruction--computed tomographic findings.

Computed tomographic findings in a case of acute intestinal obstruction due to ingested heroin packages are described. Ingestion of drug packages for the purpose of contraband transportation is a well-known method employed by drug-traffickers and intestinal obstruction may be seen as a complication. Plain radiographs and history are usually adequate for diagnosis when required for medico-legal purposes.

The role of 99mTc mebrofenin hepatobiliary scanning in predicting common bile duct stones in patients with gallstone disease.

BACKGROUND: A dilated common bile duct and/or elevated serum alkaline phosphatase, raises a suspicion of bile duct stone(s) in patients with gallstones. Cholangiography, either endoscopic retrograde cholangiopancreatography (ERCP) or magnetic resonance cholangiopancreatography (MRCP), is the best method for diagnosing bile duct stones. ERCP has the disadvantage of being invasive, and there is a risk of complications; while MRCP is costly and is not widely available. AIM: The objective of the present study was to evaluate the role of hepatobiliary nuclear scanning in diagnosing bile duct stones. METHODS: Twenty-five patients with suspected common bile duct (CBD) stones underwent hepatobiliary scintigraphy. The results of scintigraphy were compared with cholangiograms obtained by ERCP in 11 patients and MRCP in 14 patients, considering MRCP/ERCP as the 'gold standard'. RESULTS: Scintigraphy showed features suggestive of CBD stones in 11 of the 25 patients. The results of ERCP/MRCP confirmed that eight of them had stones. Scintigraphy showed no features of CBD stones in the remaining 14 patients. ERCP/MRCP showed CBD stones in two of these 14 patients. Thus, scintigraphy had a sensitivity of 80% and a specificity of 80%. CONCLUSION: We conclude that scintigraphy has good sensitivity and specificity in predicting CBD stones in patients with gallstone disease and a dilated CBD.

Tuberculous pseudoaneurysm of gastroduodenal artery.

We report a patient with Gastroduodenal artery (GDA) pseudoaneurysm of tuberculous aetiology, who presented with massive hematemesis and who was successfully managed with transarterial steel coil embolization. Pseudoaneurysms are a rare but potentially fatal complication of tuberculosis and hence early recognition and management of this complication is important. To the best of our knowledge this is the first report of a GDA pseudoaneurysm resulting from tuberculosis.

Spoke-wheel pattern in renal oncocytoma seen on double-phase helical CT.

Renal oncocytomas are benign, solid tumours of the kidney. An angiographic spoke-wheel pattern is known to be associated with oncocytomas, although it is not pathognomonic. On review of the literature, we found two reports of sonographic spoke-wheel appearance in oncocytomas. These were sufficiently characteristic to enable a confident preoperative diagnosis of oncocytoma. We present a case of a surgically proven oncocytoma with a distinct helical CT appearance, -commensurate with the angiographic and sonographic spoke-wheel appearance from which the diagnosis was suspected preoperatively.

Sonographically guided percutaneous sclerosis using 1% polidocanol in the treatment of vascular malformations.

PURPOSE: The aim of this prospective study was to assess the safety and efficacy of sonographically guided percutaneous injection of 1% polidocanol for sclerosis of peripheral vascular malformations. METHODS: Patients with vascular malformations of soft tissues were invited to enroll in the study. Gray-scale and color Doppler sonography were performed to determine the texture, margins, and size of the lesions and to determine whether high-velocity blood flow was present. Using real-time sonographic guidance, lesions were punctured with a 20/21-gauge spinal needle. When possible, venous return was occluded before injection. For each injection, 1-6 ml of 1% polidocanol was injected into 1 or more sites within the lesion. The sclerosing agent was not aspirated after injection. Repeat radiography was performed 1 month after each injection session. The procedure was repeated if the patient did not have a complete response, defined as an 80% or greater decrease in the volume of the lesion or resolution of the presenting symptoms. RESULTS: Of the 15 patients enrolled, 9 had venous malformations, 3 had lymphangiomas, 1 had a recurrent aneurysmal bone cyst, 1 had a venous pseudoaneurysm, and 1 had an arteriovenous malformation of the pinna. Each patient received 1-20 injections of 1% polidocanol (mean +/- standard deviation, 3.3 +/- 4.8 injections). This treatment resulted in a complete response of 7 venous malformations, 3 lymphangiomas, and the arteriovenous malformation and partial response of 2 venous malformations, the recurrent aneurysmal bone cyst, and the venous pseudoaneurysm. Only minor complications occurred. CONCLUSIONS: Sonographically guided percutaneous injection of 1% polidocanol for sclerosis of peripheral vascular lesions is simple, effective, and safe. This technique is especially effective in cases of soft tissue venous malformation and lymphangioma.