Milton L. Paige

Mr Imaging of Intrasellar Meningiomas Simulating Pituitary Adenomas

Over 3 1/2 years, 401 magnetic resonance studies were performed for suspected sellar-parasellar masses. Twenty-nine pituitary macroadenomas and 12 meningiomas were detected. Among the meningiomas there were three whose MR appearance simulated that of a pituitary tumor. In none of these cases was the diaphragma sellae visualized. Furthermore, in one case the prolactin level was elevated. A preoperative diagnosis of pituitary tumor resulted in an inappropriate surgical approach being used initially for its removal (transsphenoidal). Thus, nonvisualization of the diaphragma sellae and elevated prolactin levels do not exclude a nonpituitary origin of a sellar-parasellar tumor. Other methods for preoperative differentiation are discussed.

Intracavernous Carotid Artery Aneurysm Presenting as Recurrent Epistaxis

Massive epistaxis from a leaking intracavernous carotid artery aneurysm is a rare occurrence. Such an unusual case is presented with appropriate imaging and a successful treatment program.

Localized giant pseudopolyposis of the colon in ulcerative and granulomatous colitis.

The occurrence of localized large clusters of colonic pseudopolyps in 4 patients is described. The underlying disease was chronic ulcerative colitis in 2 cases and granulomatous colitis in 2 others. Each lesion presented as a bulky polypoid mass causing partial or total occlusion of the transverse segment or splenic flexure of the colon. The radiographic and pathologic features of this rare entity are illustrated, and the previously reported 10 cases are briefly reviewed.

Lingual abscess presenting as airway obstruction in the infant.

Fmm the Department of Otolaryngology-Head and Neck Surgery, McGaw Medical Center, Northwestern University-Chicago (Dr. Sanders), and the Departments of Otolaryngology-Head and Neck Surgery (Dr. Yeh), Diagnostic Radiology (Dr. Paige), and Pediatrics (Dr. Lum), Evanston Hospital-McGaw Medical Center for Northwestern University-Evanston. Submitted for publication Nov. 27, 1987; accepted Jan. 31, 1988. Reprint requests: Anthony D. Sanders, MD, Department of Otolaryngology-Head and Neck Surgery, Northwestern University, 303 E. Chicago Ave., Chicago, IL 6061 1. CASE REPORT

Cysticercosis Mimicking Brain Neoplasm: Mr and Ct Appearance

The clinical and radiologic manifestations of neurocysticercosis are varied. Since the introduction of anticysticercal drugs, surgery is only rarely needed in treatment. During the last 2 years, we have encountered two patients with minimal symptomatology whose cerebral CT and magnetic resonance studies demonstrated single lesions consisting of an enhancing nodule surrounded by edema. There was ring enhancement of the nodule in one case and homogeneous enhancement in the other. Surgery was performed in both cases, because the primary consideration was brain tumor.

Computerized tomography of malignant pleural mesothelioma with spinal canal invasion.

A case malignant pleural mesothelioma is presented. The initial CT scan of the chest showed a left paraspinal pleural mass at T6-T7 level. Subsequently the mass was partially resected by a left thoracotomy. The patient later developed spinal cord findings, and a followup CT scan showed partial destruction of the twelfth dorsal vertebra and intraspinal tumor at T11-T12 level. This is only the second case reporting spinal cord compression by mesothelioma and the first documented by computed tomography.

Hodgkin's disease of spine: Computed tomography and magnetic resonance imaging

Early recognition of spinal block in a young man by magnetic resonance imaging and immediate surgical decompression of the spinal cord by removing the epidural mass, which proved to be Hodgkins disease, was a determining factor in the complete neurologic recovery of the patient. Postoperative and postchemotherapy repeat magnetic resonance imaging showed complete resolution of the compressing mass. We believe that magnetic resonance imaging has a prominent role in the diagnosis and follow-up studies of spinal lesions without the inherent risks of other neurologic diagnostic procedures.

Detection of pneumoencephaly secondary to mechanical ventilation in neonates.

Two newborn infants with respiratory distress syndrome developed massive systemic air embolisms and pneumoencephaly. These complications occurred during positive-pressure ventilation therapy. Intracranial gas was probably due to the rupture of cerebral vessels secondary to systemic gas embolism. The diagnostic features of plain radiographs, computed tomography, and ultrasonography in the evaluation of this unusual entity are described. The importance of early CT scans of the head is emphasized.

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Osteoblastoma is an infrequent but important cause of pain in the back and neurological findings in children and young adults. Its diagnosis may be difficult and often delayed (in one series, 23% of patients had not been diagnosed after 2 years of symptoms). MRI may be useful to noninvasively image the lesion, its soft tissue and bony extent and its relationship, if any, to the spinal cord.

Magnetic resonance imaging and the diagnosis of avascular necrosis of the femoral head

Low back pain and/or pain radiating to one or both lower limbs can result from causes other than intervertebral disc disease. Recently three patients presented with low back pain radiating down the legs. When CT examination of the lumbar spine proved unrewarding, magnetic resonance imaging (MRI) was performed. Avascular necrosis (AVN) of the femoral head was diagnosed and subsequently treated before femoral head collapse occurred. In patients with unexplained low back pain, AVN of the hip should be considered and ruled out by MRI, even if conventional plain films, polytomes, and radionuclide scans are negative. The early diagnosis of AVN of the femoral head may be critical in determining whether a surgical revascularization procedure might be successful in treatment, or replacement with an endoprosthesis will be necessary, if femoral head collapse has already occurred.