Venous angiomas or developmental venous abnormalities - MR and angio-MR findings, association with cavernous angiomas and review of the literature

We used a 1.5 T superconductor MR system to study 29 patients with abnormal venous drainage. We performed basal T1 and T2-weighted sequences, T1-weighted SE sequences after 0.2 mmol/kg gadolinium-DTPA administration and angio-MR sequences rising the TOF technique as well as 2D and 3D sequences after gadolinium-D TPA administration A score system was devised to assess results: 0 when the abnormality was not displayed; 1 for display of the collector vein alone; 2 for display of the collector and medullary veins; 3 for display of the collector; medullary veins and type of drainage. We also considered the association of cavernous angiomas and a possible correlation with clinical symptoms. T1-weighted SE sequences after double dose ganolinium-DTPA administration gave the highest diagnostic accuracy (score 77) compared with basal sequences (TI score 12, T2 score 3) and with angio-MR in 24 patients (TI SE after gadolinium-DTPA score 66, angio-MR score 61). Angio-MR proved useful in disclosing the type of drainage. When 2D and 30 sequences were performed (II patients), 30 offered a good display of the vascular abnormality (6 patients). In five cases the developmental vel rous abnormality was associated with a cavernous angioma, in four cases the two malformations were closely connected. Only in two cases did the cavernous angioma present a typical ''pop-corn'' appearance. In cases with associated vascular malformations, T2-weighted SE and GE sequences were particularly useful in identifying the cavernous angioma, especially when the lesion was displayed as a low signal focal area. The venous abnormality presented as a haemorrhage in only one patient, while in another the lesion was closely connected with a low signal area in TI and T2 images probably resulting from previous haemorrhage; neither case presented associated cavernous angiomas 34% of patients had epilepsy without a clear correlation between the sire of the venous abnormality and that of the electroencephalographic abnormality To conclude venous drainage abnormalities are clearly demonstrated in MR scans using double close gadolinium-D TPA. Angio-MR should be reserved for doubtful cases in an attempt to limit the use of conventional angiography or where a display of the type of venous drainage is desired. We failed to find any clear correlation between venous abnormalities and clinical symptoms whereas potential haemorrhagic events were demonstrated even in the absence of associated angiomas.