Direct visualization of intracranial aneurysms by multiplane dynamic CT.

Using an intravenous injection of 100-150 ml contrast medium (flow, 1-1.5 ml/sec) adjacent 2-mm-thick cuts are scanned at the level of the circle of Willis. After highlighting and multilevel image summation a complete picture of the vascular anatomy of the base of the brain is obtained. In this way aneurysms as small as 2-3 mm in diameter can be detected. The method has high reliability, as indicated by the results in 31 cases.

CT diagnosis of basilar artery occlusion.

Basilar artery occlusion was diagnosed by high-resolution computed tomography (CT) in 11 cases. The normal basilar artery imaged on plain CT scans has an attenuation value not higher than that of whole blood. If the CT attenuation value of the vessel is higher than that of blood, basilar artery occlusion is probably present. The tentative diagnosis can be confirmed by comparison of the attenuation values on the pre- and postcontrast scans, preferably using multiple slices obtained by multiplane dynamic CT.

Cystic cerebral cavernous angioma with dense calcification. Case report.

A case of cavernous angioma in the right temporoparieto-occipital area is reported. The unusually large area of calcification and cystic formation presented problems in preoperative diagnosis. The tumor was treated successfully by subtotal excision.

Intracerebral arteriovenous malformation fed by both ethmoidal arteries.

A case of right-sided frontal intracerebral arteriovenous malformation fed mainly by both ethmoidal arteries is reported. The nidus was located intracerebrally, although its main feeders were dural arteries. It was drained partially through an intracerebral abnormal vein with aneurysmal dilatation of its proximal portion into the vein of Rosenthal and the straight sinus. An acute spontaneous intracerebral hematoma was the cause of the clinical symptoms. The etiology, neuroradiology, and surgical treatment of this rare entity are discussed.

Neuroradiologic and neuropathologic findings with growing giant intracranial aneurysm. Review of the literature.

The neuroradiologic observations on a case of growing giant intracranial aneurysm originating from a small saccular aneurysm are described in detail. The reports in the literature of growing giant aneurysms are reviewed. The computed tomographic and angiographic findings are described and special diagnostic difficulties analyzed. A correlation between the computed tomographic and neuropathologic findings is made, and the pathogenetic mechanisms of enlargement of aneurysms are discussed.

Nontraumatic intracerebellar hematomas: prognostic value of volumetric evaluation by computed tomography.

Thirty-two consecutive cases of nontraumatic intracerebellar hematomas detected by computed tomography are reviewed. A strong correlation was found between the clinical course and the volumetrically calculated size of the hematomas. Prompt evacuation has the best prognosis in cases that have an acute or subacute course (hematoma size, 22.5 to 66 cm3). Conservative treatment was most successful in chronic cases (hematoma size, 8 to 16 cm3). Surgical treatment should be the treatment of choice in very acute cases also (hematoma size, over 70 cm3) if the hematoma is diagnosed immediately after the onset of bleeding. Early detection and volumetric evaluation by computed tomography have great prognostic value for managing nontraumatic intracerebellar hematomas.

CT findings in hemorrhagic cerebral infarct.

Hemorrhagic cerebral infarcts can be detected by computer tomography (CT) as a high density lesion in the margins or inside a low density infarcted area. However the CT features are not always characteristic and the specific diagnosis is sometimes impossible. We describe the CT findings in initial and follow-up examinations of three arterial and one venous hemorrhagic infarcts and discuss the diagnostic problems.

[Diagnostic significance of brain tumor calcifications in the computerized tomogram]. / Diagnostische Bedeutung von Hirntumorverkalkungen im Computertomogramm.

CT investigations of 783 cases of brain tumors, which were covered by histology, were checked with regard to frequency and configurations of calcifications. As expected the calcifications were detected more frequently by CT than by conventional radiology because of higher resolution. Most frequently calcifications were detected in craniopharyngeomas (72%) and in oligodendrogliomas (51%). The calcifications shown by CT can be changed by variation of technical parameters. Certain patterns of calcifications can be differentiated, if constant and best technical conditions are used. One single pattern cannot be specific. A homogeneous calcification of the tumor as a whole has been observed in meningeomas only. For other brain tumors calcifications are useful for the diagnosis, if localisation, density, and reaction of the surrounding tissue after injection of contrast medium and clinical data are known.

Computed tomography histogram in the pathologic definition of supratentorial brain tumors.

After studying the histograms of 87 supratentorial brain tumors and 4 abscesses before and after contrast medium injection and analyzing the results, we attempt to determine characteristic signs of the various kinds of tumors in order to improve their pathologic definition. The meningiomas, astrocytomas, and abscesses seem to show the most standard signs. The metastases are the most variable kind of tumors.

Subdural hematoma associated with dural metastatic tumor.

Two cases of subdural hematoma associated with dural metastasis are reported. The computed tomographic and angiographic features are presented. The possible pathogenetic mechanism is discussed. Our cases support the idea of obstruction of dural capillaries by neoplastic cells and subsequent subdural bleeding.

Oligodendrogliomas: CT patterns with emphasis on features indicating malignancy.

Computed tomography (CT) of 22 patients with histologically verified oligodendroglioma showed calcifications in 20 cases and contrast enhancement in 14. All of the enhancing cases proved to have malignant histological features. In 2 of the 14 malignant tumors, definite CT evidence (fluid-fluid level) of a cystic component was present.

Bilateral reversible thalamic lesions on computed tomography.

Bilateral approximately symmetrical hypodense areas located in the thalamus were encountered in two patients who recovered clinically. Regression of the lesions could be observed on CT. The clinical symptoms corresponded to the thalamic location. Since these two patients recovered, no autopsy material is available to prove the nature of the causative lesion, although the etiology is most probably inflammatory.