INTRAOPERATIVE COLOR-DUPLEX-SONOGRAPHY IN THE SURGICAL-MANAGEMENT OF CEREBRAL AV-MALFORMATIONS

In this prospective study the role of intra-operative Colour-Duplex-So nography (= CDS) during surgery of arteriovenous malformations (= AVM) is evaluated. During the last three years 20 consecutive patients wit h supratentorial AVMs were examined by intra-operative CDS in order to evaluate the potential of CDS to 1) localize the AVM, 2) differentiat e between embolized and perfused parts, 3) identify feeding and draini ng vessels and 4) control the complete excision of the AVM. All AVMs w ere localized supratentorially, 9 were grade I and II (according to Sp etzler and Martin [31]), 8 grade III and 3 grade IV. 11 were partly em bolized and 8 associated with an intracerebral bleeding. In all cases the nidus was correctly localized sonographically by its typical bidir ectional flow pattern in Colour-mode. CDS guided the surgeon directly to all(ll cases) deep-seated AVMs (2 to 4cm subcortically). The smalle st nidus measured 10 mm. 28 of 34 angiographically defined main feedin g and 18 of 23 draining vessels were identified. 14 patients were cont rolled sonographically at the end of the resection regarding the compl eteness of excision. In 11 patients CDS was negative and was confirmed by either postoperative angiography or MRI in 10 patients. In one cas e residual AVM tissue was missed by CDS. Positve CDS findings in 3 cas es were all confirmed by microscopic re-inspection, angiography and CC T. Our results suggest that CDS is able to localize AVMs intra-operati vely with minimal instrumentation. It allows safe navigation to deep-s eated malformations with high accuracy. Feeding and draining vessels c an be identified and completeness of resection can be controlled.