Avoidance of Major Vascular Injury in Transcranial Brain Tumor Surgery Using Real-Time Doppler Navigation: Technical Note and Case Series

BACKGROUND AND OBJECTIVES:In endoscopic endonasal surgery, the Doppler probe has proven useful for localizing the paraclival and cavernous internal carotid arteries (ICA) and avoiding ICA injury. Similarly, during transcranial brain tumor removal, the Doppler probe may help avoid major vascular injury, particularly for tumors encasing or adherent to Circle of Willis branches. In this study, we describe the technique, outcomes, and potential neurovascular benefits of real-time navigation using the Doppler probe during craniotomy for brain tumor removal.METHODS:Patients from 2015 to 2022 who underwent craniotomy for brain tumor resection and the Doppler probe was used were retrospectively analyzed. Data collection included demographics, tumor pathology, incidence of major/minor vascular injury, MRI-confirmed stroke/infarction, and extent of tumor resection.RESULTS:In total, 695 patients underwent 840 craniotomies for brain tumor resection; in 501 craniotomies (59.6%), the Doppler was used. One major vascular injury (0.2%) of a supraclinoid ICA was directly attributed to non-Doppler probe use immediately before vessel injury, leading to stroke and severe neurological decline. There were 7 strokes (1.4%) leading to permanent neurological deficit attributable to vasospasm or small vessel injury and 26 asymptomatic infarctions/strokes (5.2%) attributable to unrecognized vascular injury or spasm at the time of surgery.CONCLUSION:In this series of 501 craniotomies for brain tumor removal where the Doppler probe was used, the rate of direct large vessel injury was under 1%. Although our data show that smaller vessel injuries can still occur and may lead to permanent neurological deficits, routine Doppler probe use may help guide tumor dissection and aggressiveness of removal, avoiding inadvertent major arterial injury. Our experience suggests that it is most useful as tumor dissection progresses as the resulting brain shift makes stereotactic neuronavigation less reliable. We recommend routine Doppler probe use during transcranial brain tumor removal, particularly for tumors encasing or adherent to major arteries.