Adel G. Mattar

Intracranial pearly tumors : The roles of computed tomography, angiography, and pneumoencephalography

The findings is computed tomography (CT) and other radiological examinations in nine histologically proven cases of intracranial pearly tumors are presented. The CT findings include a low density lesion with no enhancement after contrast medium injection and in some cases a lesser degree of mass effect than would be expected from the size and site of such lesions. Pneumoencephalography is superior to CT in detecting suprasellar pearly tumors when they are isodense with the cerebrospinal fluid.

Three-phase bone scintigraphy. Asymmetric patterns in the upper extremities of asymptomatic normals and reflex sympathetic dystrophy patients.

Three-phase Tc-99m MDP scans of 61 patients with asymptomatic upper extremities randomly mixed with 17 studies of patients previously diagnosed with reflex sympathetic dystrophy were blindly interpreted by three observers. Asymmetry in any of the phases was recorded and a final diagnostic impression made. Thirteen of 17 reflux sympathetic dystrophy studies were rated abnormal by at least two observers. Mild to striking asymmetry was occasionally seen in all three phases in asymptomatic upper extremities. Twenty of 61 asymptomatic patients (33%) were rated abnormal by at least one observer, and 5 of 61 studies (8%) were rated abnormal by all observers. Asymmetries in normal patients occurred more commonly in the earlier phases, while asymmetry in the delayed images was mild in all but one. Tightening the criteria to exclude mild asymmetry in delayed images resulted in unacceptably low sensitivity for reflex sympathetic dystrophy (29%). Interob-server variability was most prominent in the flow and immediate images. In the diagnosis of reflex sympathetic dystrophy a greater reliance should be placed on the delayed images, which in themselves have an overall sensitivity of 94%. It is important, however, to recognize that occasional mild and rare moderate asymmetries in even the delayed images of normal individuals result in an overall lower specificity of 77%.

Malformation of the cerebral cortex with heterotopia of the gray matter.

Developmental malformation of the cerebral cortex with heterotopia of the gray matter is a rare condition. It can present as unilateral megalencephaly, a localized mass, or focal cortical dysplasia. Four histologically confirmed cases are described in this report, and the findings from computed tomography as well as from other radiological diagnostic procedures are discussed.

Scintigraphic and radiographic appearance of osteomas in Gardner's syndrome.

Increased uptake in the maxilla and mandible on bone scanning is not unusual and is most commonly attributed to periodontal disease. However, sometimes atypical findings suggest other diagnoses. A 22-year-old woman with Gardners syndrome had a bone scan to investigate a soft tissue mass in the shoulder. Intense uptake in the maxilla and mandibles was demonstrated, which was related to osteomas, a common finding of this syndrome.

An atlas of renography with Tc-99m sestamibi comparison with Tc-99m DTPA

Tc-99m sestamibil demonstrates considerable renal uptake followed by net urinary clearance similar to that of creatinine. The authors have previously shown that renograms could be obtained in cardiac patients by imaging during the rest injection of the perfusion agent. The present study shows correlating Tc-99m sestamibi and Tc-99m DTPA studies in hypertensive patients with a spectrum of findings, including aortic aneurysms, asymmetry due to renovascular disease, cysts, bilateral renal dysfunction, and horseshoe kidney. Tc-99m sestamibi images have persisting background activity in the liver and spleen, but show renal structure and function in adequate detail. Quantitative analysis confirms that Tc-99m sestamibi has higher renal uptake, but less excretion than Tc-99m DTPA. Review of these correlating studies suggests straightforward transfer of diagnostic expertise with standard renography to this new application.