Inferior petrosal sinus: imaging-anatomic correlation.

PURPOSE: To correlate computed tomographic (CT) or magnetic resonance (MR) images with dissections of normal inferior petrosal sinuses (IPS). MATERIALS AND METHODS: Postmortem dissection was performed in 12 individuals, one of whom had undergone CT and MR imaging 3 months before death. Seven patients underwent IPS venography, CT, and MR imaging. One hundred sixteen patients with normal IPS underwent MR imaging; 40, CT and MR imaging; and two, CT, MR imaging, and arteriography. RESULTS: Images showed that the IPS and basilar plexus formed conspicuous, enhanced structures that provide much of the border between the clivus and cerebrospinal fluid. Axial, cross-sectional IPS dimensions were as large as 9 x 16 mm. The larger sinuses were contained by deep grooves of bone that sometimes showed marked cortical thinning. Sixty-nine (39%) of the 175 individuals studied had markedly asymmetric IPS. CONCLUSION: CT and MR images showed that normal IPS and basilar plexus vary in size and are frequently asymmetric. This range of normal measurements and appearances should be taken into account before abnormalities in this region are diagnosed.

The lumbosacral plexus: anatomic-radiologic-pathologic correlation using CT.

Before high resolution computed tomography (CT), the lumbosacral plexus was nearly impossible to image. While individual elements of the plexus are not consistently resolved using CT, the regional anatomy is reproducible and allows accurate evaluation. Normal regional anatomy was established by axial cadaver dissection and review of 233 normal computed tomographic examinations. This regional anatomy has been presented in detail. In addition, 17 patients with lumbosacral plexopathy due to benign, neoplastic and idiopathic causes were imaged. Our results show that CT is effective in the evaluation of suspected structural lesions of the lumbosacral plexus.

Hematochezia and the false negative Meckel's scan: a continued need for barium studies.

A patient with hematochezia and a false negative Meckel's scan is presented. A Meckel's diverticulum was subsequently diagnosed on barium small bowel follow-through. Meckel's diverticulum is discussed with emphasis on the relationship of barium and radionuclide studies.

Chemotherapy port "Twiddler's syndrome". A need for preinjection radiography.

Potentially serious extravasation of vincristine occurred when a chemotherapy port, inadvertently withdrawn from the subclavian vein by the patient, was injected. Plain radiography suggested withdrawal of port tubing which was later proven by contrast injection. The need for awareness of possible patient manipulation of their indwelling ports and routine preinjection radiography is suggested.

Agenesis of the corpus callosum: sonographic features.

Sonographic features of agenesis of the corpus callosum and its related intracranial abnormalities are described in four patients. A brief review of clinical, radiologic, and pathologic manifestations of agenesis of the corpus callosum is presented. Both agenesis of the corpus callosum and its potentially serious associated intracranial abnormalities can be effectively diagnosed with transfontanelle sonography.

Cerebrospinal fluid abdominal cyst. Computed tomographic resolution of a sonographic dilemma.

A case of subhepatic cerebrospinal fluid cyst, an uncommon complication of ventriculoperitoneal shunting, is presented. Sonography could not reliably prove shunt tubing to be entering the cystic spaces. Results of computed tomography scanning were definitive.

Gas as a mass: a symptomatic spinal canalicular collection.

A symptomatic collection of spinal canalicular gas of degenerative origin was observed by computed tomography. Relief of symptoms followed gas aspiration. The collection involved the lateral recess. Such gas collections do not appear to represent benign, transient entities in all patients.

Brachial plexus: anatomic, radiologic, and pathologic correlation using computed tomography.

Computed tomographic (CT) anatomy of the normal brachial plexus was analyzed in 50 patients with nonneurologic disease. Identification of anatomic structures on the CT images was facilitated by comparison with cadaver cross sections. Ten patients with clinical brachial plexopathy were also examined. Of these 10 patients, 7 demonstrated lesions of the brachial plexus. Computed tomographic examination of the brachial plexus is useful in detecting mass lesions of the plexus and may allow earlier diagnosis and specific therapy. Whether CT will be reliable in distinguishing idiopathic brachial plexopathy from the plexopathy associated with pathological lesions awaits further study.