Stereotactic microresection of small cerebral vascular malformations (SCVM)

Between 1988-1993 we performed CT-stereotactic guided microsurgical resection as a one-session-procedure in 46 patients bearing small (< 30 mm) cerebral vascular malformations (SCVM). The location of the SCVM was deep subcortical in 38 patients, temporal medio- basal in 3 and brainstem in 5. The surgical technique intended to minimise invasiveness by reducing the operative approach to a size less than the diameter of the lesion concerned. The mean diameter of our SCVM's was 20 mm ranging from 10 to 30 mm. Histologically we found 23 arteriovenous malformations, 22 cavernous malformations and 1 capillary telangiectasia (capillary malformation). Clinical symptomatology consisted mainly of seizures, (progressive) neurological deficit and (minute) acute intracerebral bleeding. The SCVMs could be demonstrated by contrast-enhanced CT as well as by MRI. 15 of the AVM's revealed as angiographically occult. Complete microsurgical resection of the SCVM was accomplished in all cases with a surgical morbidity of 6.5% and no operative mortality. In 14 patients, most of them with initial acute intracerebral haemorrhage, the pronounced focal neurological deficit improved. During the follow-up period (1/2-5 years) no rebleeding occurred. As far as epileptic seizures were concerned 13 patients became seizure-free without anticonvulsants and 11 patients seizure-free with anticonvulsant, in the remaining 4 patients seizures were reduced in frequency.