Computerized axial tomography of intracerebral hematoma. A clinical and neuropathological study.

Excellent correlation between computerized axial tomographic (CT) scans and the location and extent of pathologically verified intracerebral hematomas was demonstrated in eight patients. Superficial and intraventricular extension, hydrocephalus, and mass effect were easily identified; CT scanning was superior to angiography and radionuclide brain scanning in diagnosing hematoma and in determining its extent and associated ventricular size. Angiography was superior to CT scanning in demonstrating aneurysms and arteriovenous malformations as a cause of intracerebral hematoma. Computerized axial tomographic scanning is also useful in following the resolution of hematomas and in guiding surgical intervention.

Aphasia following pluridirectional tomography with metrizamide. The effect of patient position.

Eight of 67 patients became transiently aphasic after myelography or cisternography with metrizamide. All eight patients had been placed in the left lateral decubitus position for pluridirectional tomography. Immediate EEGs revealed focal left-sided abnormalities in two patients. In one other patient, a computed tomographic scan showed contrast mainly over the left hemisphere. All of the symptoms resolved within 48 hours. In 34 patients who were placed on the right side, no language disturbance was noted. Aphasia after pluridirectional tomography with metrizamide may be due to local irritation of the perisylvian language centers of the dominant hemisphere. The phenomenon is distinct from syndromes of generalized confusion. The complication may be avoided by placing patients in a right lateral decubitus position for pluridirectional tomography.

Magnetic resonance imaging in young adults with cerebral infarction due to moyamoya.

The number, size, and location of cerebral infarctions, and blood flow in the middle cerebral artery as seen on proton magnetic resonance imaging were assessed in six white adults with angiographically documented moyamoya. Findings were correlated with clinical presentation, computed tomography, and angiography. Large hemispheric infarctions were found in five hemispheres, predominantly in watershed regions. Subcortical infarctions (n = 56) were found in all hemispheres. They were predominantly located in the centrum semiovale, in the distal beds of supply of the penetrating branches of the anterior and middle cerebral arteries. Infarction of the putamen was found in three hemispheres, caudate nucleus in four, globus pallidus in two, and anterior limb of the internal capsule in two. There were none in the posterior limb of the internal capsule, thalamus, brain stem, or cerebellum. Middle cerebral artery flow was visualized as a signal-void flow sign in only three hemispheres. Cerebral infarctions due to moyamoya are bilateral, multiple, often small, and asymptomatic, affecting predominantly the carotid circulation in watershed regions. Subcortical infarctions in the centrum semiovale and large hemispheric infarctions in hemodynamically compromised areas are the predominant findings.

Intracranial hemorrhage produced by spontaneous dissecting intracranial aneurysm.

Two patients with intracranial dissecting aneurysms were seen initially because of acute hemorrhage. One patient died, and a false dissecting aneurysm secondary to atherosclerosis was found at autopsy. In the other patient, the appearance of the carotid arteriogram was typical of a dissection. Because of the propensity of these aneurysms to rupture, caution is indicated in the use of anticoagulants or vasopressors in patients with evolving cerebral infarction secondary to intracranial arterial dissection.

Global aphasia without hemiparesis.

Three patients acutely developed global aphasia, but did not manifest the typical accompanying right hemiparesis. Computed tomography and magnetic resonance imaging studies demonstrated that the patients had two discrete left hemisphere lesions, one in the anterior language cortices or language-related subcortical areas, and one in the posterior language cortices. Cerebral angiography showed that two patients had complete occlusion of the left internal carotid artery, and the third had an intraluminal "clot" in the supraclinoid portion of the left internal carotid, findings suggestive of an embolic etiology. Our cases indicate that global aphasia without hemiparesis predicts two discrete lesions and a particularly good recovery of speech and language.

Management of radiation-induced accelerated carotid atherosclerosis.

Patients with long survival following cervical irradiation are at risk for accelerated carotid atherosclerosis. The neurologic presentation in these patients mimics naturally occurring atheromatous disease, but patients often present at younger ages and with less concurrent coronary or systemic vascular disease. Hypercholesterolemia also contributes to this accelerated arteriosclerosis. Angiographic findings in this disorder include disproportionate involvement of the distal common carotid artery and unusually long carotid lesions. Pathologic findings include destruction of the internal elastic lamina and replacement of the normal intima and media with fibrous tissue. This article describes two surgical patients with radiation-induced accelerated carotid atherosclerosis who typify the presentation and characteristics of this disease.

Time course of satisfaction of search.

"Satisfaction of search" (SOS) refers to the effect in which a second lesion remains undetected after detection of another lesion on the same radiograph. The objective of this study was to clarify our understanding of SOS by relating it to total time of inspection and time intervals before, between, and after discovery of lesions. Detection accuracy of native lesions in chest radiographs, before and after the addition of a simulated nodular lesion, was measured for ten observers. Analysis of data from this and a previous experiment showed that average perceptual accuracy of individual receiver operating characteristic curves was significantly reduced with the addition of the nodules. Plots and analyses of search time revealed that, on average, during a typical 46-second inspection of a case, simulated nodules were found at 18 seconds, native abnormalities at 25 seconds, and false positives occurred at 33 seconds. Time needed to find nodules did not depend on whether native lesions were present; time to find native lesions did not change with addition of nodules; and total search time was the same for images with one, two, or no lesions. The detection results show that the SOS effect was obtained, but that interrupting search in order to measure it also diminishes accuracy. Analysis of the time course data relates SOS to perceptual capture and strategic halting of search.

Nontraumatic lobar intracerebral hemorrhage: CT/angiographic correlation.

Cerebral angiography in patients with nontraumatic lobar intracerebral hemorrhage may or may not uncover the underlying cause of the disorder. The CT and cerebral angiographic studies of 67 consecutive patients with nontraumatic lobar intracerebral hemorrhage were reviewed to assess the relationship between CT pattern and location of hemorrhage and the frequency of diagnostic angiographic findings. Origins of these hematomas were also determined and correlated with radiographic findings. CT revealed 26 temporal, 18 frontal, 17 parietal, three occipital, and three multiple lobar hematomas. Thirty-three patients had "pure" lobar hematomas, 12 had coexistent intraventricular hemorrhage, 12 had associated subarachnoid hemorrhage, and 10 had both intraventricular and subarachnoid hemorrhage accompanying their lobar hematomas. Angiographic findings were diagnostic in 29 cases (43%). In the presence of accompanying subarachnoid hemorrhage, angiographic findings were diagnostic in 17 (77%) of 22 patients; in its absence, angiography was diagnostic in 12 (27%) of the remaining 45 patients. Diagnostic angiograms were also more frequent in the presence of a frontal or temporal lobar hematoma than with a parietal or occipital lobar hematoma. While CT patterns do influence the frequency of diagnostic angiographic findings, cerebral angiography is recommended in all patients with otherwise unexplained nontraumatic lobar intracerebral hemorrhage.

Diagnosing intracranial vasculitis: the roles of MR and angiography.

PURPOSE: To describe our experience with MR and angiography in diagnosing intracranial vasculitis and to test the hypothesis that MR can be used to screen for patients unlikely to have vasculitis. METHODS: Ninety-two patients who had angiography with "exclude vasculitis" as the indication or who had angiography and a clinical diagnosis of vasculitis were identified. Angiograms of all 92 patients and the MRs of the 70 patients who had both studies were reviewed. RESULTS: Eleven patients had intracranial vasculitis. Angiography showed characteristic changes in 8. MR, performed in 9 of 11 vasculitis cases, was significantly abnormal in all 9. Among 70 patients who had both studies, 19 had MR that was completely normal or showed only incidental findings. None of these 19 was diagnosed with vasculitis. The diagnostic yield of angiography performed to exclude vasculitis was only 6%. CONCLUSIONS: Evaluation for intracranial vasculitis should include MR. A negative MR excludes intracranial vasculitis more definitively than does a negative angiogram and makes the likelihood of finding vasculitis with angiography negligible.

Suprasellar arachnoid cysts: 2. Evaluation of CSF dynamics.

Suprasellar arachnoid cysts are an infrequent but surgically remediable cause of hydrocephalus and neurologic deficits. The optimal method of treatment varies according to whether the cyst communicates with the subarachnoid space; the presence or absence of associated hydrocephalus; and the exact site(s) and severity of intraventricular and extraventricular cerebrospinal fluid (CSF) obstruction. Eight patients with suprasellar arachnoid cysts are described to emphasize the importance of pretherapeutic investigation of CSF dynamics. The variability of the ventriculocisternal-cyst CSF dynamics and the value of metrizamide computed tomographic cisternography and ventriculography in investigation of the CSF pathways are stressed. A diagnostic approach to the evaluation of the CSF dynamics is outlined, based on whether hydrocephalic or compressive symptoms predominate.

Suprasellar arachnoid cysts: 1. CT recognition.

Suprasellar arachnoid cysts are basal midline masses that represent a rare but surgically remediable cause of hydrocephalus and neurologic deficits. These cysts represent a diagnostic challenge and often go unrecognized for many years. The authors review the computed tomographic (CT) findings in seven patients with documented suprasellar arachnoid cysts and define previously undescribed diagnostic criteria. These cysts usually can be differentiated from cystic midline neoplasms by their CT density, homogeneity, and location as well as by their lack of fat, lack of calcification, and absence of contrast enhancement. Accurate distinction from marked third-ventricular enlargement secondary to obstructive hydrocephalus and from third-ventricular ependymal cysts can be made on the basis of basal cisternal expansion, distinctive mass effect and displacement, the characteristic shape and contour of the apparent "third ventricle," and the appearance of structures at the foramen of Monro. Although metrizamide CT ventriculography and cisternography allow confirmation of the diagnosis and evaluation of cerebrospinal fluid dynamics, these definitive studies will not be obtained unless the cysts are first suspected by their conventional CT appearance.

Isolated central nervous system angiitis first presenting as spontaneous intracranial hemorrhage.

Two cases of isolated central nervous system angiitis presenting as spontaneous intracranial hemorrhage are reported. The usefulness and limitations of cortical/leptomeningeal biopsy in this condition is described. Emphasis is placed on the clinical awareness of this unusual association to ensure early recognition and prompt management with immunosuppressive therapy.

Management of vein of Galen aneurysms. Report of two cases.

Aneurysms of the great vein of Galen are rare and potentially lethal lesions, especially in early infancy. Sectioning of the feeding arteries and excision of the lesions have been proposed for the best long-term results. An alternative approach was utilized in the two children discussed here. The computerized tomography (CT) scan established the precise diagnosis and demonstrated hydrocephalus and cortical atrophy preoperatively. Parieto-occipital craniotomy with an interhemispheric approach was performed to clip the numerous feeders. The procedure was terminated when the sac collapsed and blood aspirated from the lesion was venous in oxygen saturation. A Doppler probe over the aneurysm then revealed a venous flow. Serial postoperative CT scans demonstrated that the mass had shrunk in size. Follow-up angiography was not thought necessary.