[Neuroradiologic diagnosis and clinical aspects of giant intracranial aneurysms]

The CT and angiographic findings of 33 patients with intracranial giant aneurysms are reported. In the non-thrombosed giant aneurysms, CT showed a homogeneous, primarily hyperdense space-occupying lesion with strong enhancement. The partially thrombosed giant aneurysms appeared hyperdense with hypodense or isodense portions in the plain CT scan. The completely thrombosed giant aneurysms were isodense to hyperdense. In none of the 33 patients could perifocal edema be proved. A CT diagnosis was possible in every case of partially or non-thrombosed aneurysms. Pre-operative angiography in these cases was necessary only for purposes of vessel topography. Five completely thrombosed giant aneurysms could not be identified in either CT or the angiogram so that the diagnosis was not made until surgery. The clinical findings of these five cases of subarachnoid hemorrhage and 28 patients with signs of intracranial space-occupying lesions were diagnostically misleading, as they suggested an intracranial tumor.