We report our findings with digital subtraction angiography (DSA), computed tomography (CT) and magnetic resonance imaging (MRI) in six patients with a diagnosis of infratentorial angioma. In 2 of these patients this diagnosis was confirmed at histology. DSA failed to show the nidus of the angioma in all patients (cryptic angioma) but revealed a neighbouring venous angioma in one. Plain CT scans performed in 3 patients in the subacute phase (within 20 days of the initial symptoms) showed a small hyperdense area consistent with a haemorrhage and/or calcifications; contrast enhancement was minimal in one and absent in two. A late CT scan (1 month after the initial symptoms) was performed in 5 patients. In 4 of these CT showed calcifications as well as hypodense or isodense areas presumably due to previous bleedings. In one case CT revealed a tissue of slightly increased density located in the lower pons. Contrast enhancement was absent in two and minimal in three patients. The venous malformation demonstrated by DSA was clearly shown by the enhanced CT scan. MRI performed during the first month in two patients detected traces of blood products. Five patients (one of whom was a follow-up study) were examined during the chronic phase (after 1 month) and MRI showed the presence of methaemoglobin, haemosiderin and/or calcifications. The draining vein of the venous angioma was clearly visualised. In our experience, CT scan seems to be useful in detecting blood collections in the subacute phase and small calcifications in the chronic phase. MRI is very helpful in detecting traces of previous bleedings in the chronic phase, although the MRI pattern is not specific and may be seen in brain stem tumours.
|Number of pages||12|
|Journal||Journal of Neuroradiology|
|Publication status||Published - 1988|
ASJC Scopus subject areas
- Clinical Neurology
- Radiology Nuclear Medicine and imaging
- Radiological and Ultrasound Technology