Evaluation of recent cerebral infarction by computerized tomography.

Twenty patients with cerebral infarction were observed with serial computerized tomographic (CT) scans. Seventy percent of those infarctions showed a mass effect that had disappeared in all patients by the eighth week after the ictus. In 63%, there was enhancement after contrast infusion, with a definite temporal relationship to the day of onset of the neurological deficit. Twenty percent of the patients initially had normal CT scans that became abnormal weeks after the stroke. Radionuclide scans were positive in the patients who showed contrast enhancement, and the area of abnormal uptake correlated well with the area of enhancement. The timing of the performance of the CT scan in relation to the onset of neurological deficit is an important factor to consider when evaluating the stroke syndrome with CT.

Cerebellar venous angiomas. A continuing controversy.

We have studied three patients with angiographically documented cerebellar venous angioma (CVA). One patient had a subacute cerebellar hematoma and underwent posterior fossa craniotomy for evacuation of the hematoma and excision of the malformation. A hemorrhagic venous infarction of the brain stem and cerebellum occurred, and the patient died three weeks postoperatively. A second patient with an unruptured CVA had a history of headaches, tinnitus, and vertigo. Conservative treatment was elected, and the patient's condition remains unchanged after 11 months of follow-up. The third patient, recently diagnosed as having an unruptured CVA had episodic vertigo and disequilibrium. Conservative treatment was chosen, and he is asymptomatic after six months of follow-up. Based on a review of 24 other cases of CVA plus our experience we could not conclude any definite trend regarding natural history or treatment. However, conservative treatment seems the logical choice in patients with unruptured CVA.

Radiologic evaluation of tuberculous meningitis.

Five cases of primary tuberculous meningitis are presented. In three cases of acute meningeal process, the classic computed tomographic (CT) scan findings of basal meningeal enhancement, hydrocephalus and arteritis on angiography were found. These radiologic findings suggested the diagnosis, and antituberculosis treatment was therefore instituted at an early stage of the disease. In the remaining two cases with late complication of tuberculous meningitis, hydrocephalus and basal vessel arteritis were present. The importance of correlation of the clinical and radiographic findings is discussed.

Magnetic resonance imaging (MRI) effects on rat pineal neuroendocrine function.

This study investigated the effects of MRI on receptor-mediated activation of pineal gland indole biosynthesis. Exposure of rats to MRI reduced the effects of isoproterenol on pineal serotonin and N-acetylserotonin levels suggesting that strong magnetic fields and/or radio-frequency pulsing used in MRI inhibited beta-adrenergic activation of the gland. There was no effect of MRI on saline controls.

CT and MR of temporal bone malignancies primary and secondary to parotid carcinoma.

PURPOSE: To review the CT and MR characteristics of temporal bone malignancy, and to evaluate the relationship between malignancies of the temporal bone and parotid gland. METHODS: A group of 15 surgical patients with diagnosis of temporal bone malignancy were retrospectively reviewed. These included 11 cases of primary temporal bone malignancy and four cases of secondary carcinoma of the temporal bone from a primary tumor of the parotid gland. Three primary temporal bone malignancies were recurrences, and two secondary tumors were parotid recurrences. RESULTS: Five of the 11 patients with primary temporal bone malignancy had parotid infiltration (45%). All four patients with secondary temporal bone destruction caused by parotid carcinoma had erosion of the mastoid, two with erosion of the external auditory canal, and one of the middle ear. CONCLUSIONS: It is important radiographically to recognize the close relationship between malignancies of the temporal bone and parotid gland, because either may secondarily invade the other. Suspicion of malignancy in either the temporal bone or parotid gland necessitates complete imaging of the other structure. Temporal bone or skull base erosion were best seen on CT at bone algorithm. MR with and without infusion provided excellent delineation of soft-tissue tumor margins, muscle infiltration, intracranial extension, and vascular encasement.

Optic nerve tumors: role of magnetic resonance imaging and computed tomography.

Localization and pathologic diagnosis of optic nerve tumors have been greatly improved by high resolution computed tomography and magnetic resonance imaging. Radiologic differentiation of the most common tumors of the optic nerve (meningioma and glioma) can be made by using these new imaging modalities. Early diagnosis of optic nerve lesions has resulted in better prognosis and surgical outcome.

MRI and CT of sellar and parasellar disorders.

Discussion of the anatomy of the parasellar region focuses on the optic chiasm and its relationship to surrounding structures. CT and MRI are valuable tools in the imaging of these regions. This article provides a brief review of the technique of CT and MRI with visualized anatomic structures of these areas. A closer look at how CT and MRI are used to delineate the different pathologic processes of the sellar and parasellar regions then follows.

Malignant metastasizing angioblastic meningiomas.

The authors report and discuss the unusual clinical and roentgenographical features of three cases of angioblastic meningioma with extracranial metastases. The primary lesions occurred in the cervical canal, the parasagittal region, and the posterior fossa. Metastases were to lungs, liver, pancreas, and kidneys.

Neonatal craniopharyngioma. Case report.

The authors report a case of craniopharyngioma in a newborn infant. Marked hydrocephalus of the fetal head was recognized in the pelvimetric roentgenograms of the mother and massive suprasellar calcification was seen in the plain skull films.

Clinical course of pediatric congenital inner ear malformations.

OBJECTIVE: To determine any factors that could improve the early detection and management of congenital inner ear malformations. STUDY DESIGN: A retrospective review was performed of all patients with a diagnosis of inner ear malformation at Loyola University Medical Center (LUMC) and the Hospital for Sick Children (HSC) between 1987 and 1995. Clinical records and audiometric data were accumulated. One neuroradiologist reviewed every temporal bone computed tomography (CT) scan. METHODS: Forty-six pediatric patients with congenital inner ear anomalies evaluated at two tertiary care hospitals. RESULTS: The average patient age at initial assessment was 25.7 months. A family history of hearing loss was noted in only five patients (12.8%). A major nonotological deformity was seen in 41% of patients. The average hearing threshold was 88 dB. All three patients with sudden hearing loss had vestibular aqueduct enlargement. Two of the three patients with common cavity anomalies had a history of recurrent meningitis. Twenty-seven patients had a vestibular aqueduct deformity, the most frequent radiographic abnormality in the series. CONCLUSIONS: Because inner ear malformation was diagnosed after 24 months of age in a significant percentage of patients, we recommend increased parental education and vigilance by primary care practitioners. Universal newborn screening may be the key to earlier detection of these infants. For children with idiopathic sensorineural hearing loss, we recommend a temporal bone CT scan. Patients with vestibular aqueduct enlargement must be counseled about the risk of progressive sensorineural hearing loss, meningitis, and the need to avoid contact sports. Patients with common cavity abnormalities should be considered for exploratory tympanotomy and also educated about the risk for meningitis.

Optimal clip application and intraoperative angiography for intracranial aneurysms.

BACKGROUND: The actual incidence of residual aneurysm after clipping is unknown. The natural history of residual aneurysm can be regrowth and hemorrhage. Intraoperative angiography offers a cost-effective, safe interdiction to the problem of residual aneurysm and parent vessel stenosis. METHODS/RESULTS: Forty consecutive patients harboring 54 aneurysms underwent 42 operative procedures to clip 52 aneurysms, during which 220 intraoperative angiographic runs were performed. Ninety-three percent of the procedures were performed on patients with acute subarachnoid hemorrhage. There were 4 giant (>2.5 cm, 4/52 = 8%, all anterior circulation), 21 large (1.0-2.5 cm, 21/52 = 40%, 16/ 21 = 76% anterior circulation, 6/21 = 28% posterior circulation), and 27 small (<1.0 cm, 27/52-52%, 22/27 = 81% anterior circulation, 5/27 = 18% posterior circulation) aneurysms. Intraoperative angiography led to clip adjustment in 18/52 = 34% of aneurysms (4/18 = 22% for parent artery stenosis, 8/18 = 44% for residual aneurysm and 6/18 = 33% for both). Of the 18 adjustments made, 16 = 88% were made on giant or large aneurysms and two were small (one was a complex anterior communicating and one was a vertebral junction aneurysm). Follow-up angiography was performed on 26/42 = 62% of operative cases. Postoperative angiography confirmed intraoperative angiography in all cases. Two complications occurred during 220 angiographic runs: one embolic stroke and one incident of equipment failure. CONCLUSION: A grading scale was applied to test the relationship between anatomical site and size as they relate to the necessity for clip adjustment for complete aneurysm obliteration and/or parent artery compromise. Significance was related to site (basilar bifurcation, anterior communicating, middle cerebral bifurcation, and ophthalmic) and size (>1.0 cm), both as independent and codependent variables. An analysis of the cost-effectiveness of intraoperative angiography was demonstrated.

Evaluation of intracerebral hematoma by computed tomography.

The CT scan appearances of acute intracerebral hematoma are usually diagnostic, and can be differentiated from hemorrhagic tumor and infarction. Some prognostic evaluations can be made, depending on the site and size of the hemorrhage. Sequential studies indicate resolution of the density of the hematoma over a period of approximately six weeks. This however does not appear to correlate with pathological resolution, but does reflect the hemoglobin concentration in the hematoma. Angiography is indicated when an underlying AVM or aneurysm is suspected, whereas contrast infusion studies are not of great value in detecting these lesions.

Radiology of anterior cerebral artery infarction.

Twenty patients with anterior cerebral artery infarction are reviewed. Usual and unusual clinical presentation and radiographic findings (angiography and computed tomography) are correlated.