[The role of intraoperative flowmetry in surgery of cerebral aneurysms]

Aim of the study was to assess the capabilities of intraoperative ultrasonic flowmetry in cerebral aneurysm surgery for prevention and immediate correction of cerebral ischemia. Ultrasonic flowmeter (Model HT313/323, "ransonic Systems Inc.", USA) was used during surgery in patients with complicated, large and giant aneurysms for evaluation of cerebral blood flow in main arteries (internal carotid, anterior and middle cerebral) and their branches (branches of M2-M3 and A2 segments). The series included 20 adult patients (13 male and 7 female) operated in Burdenko Moscow Neurosurgery Institute during 2008-2011 years. Mean age was 47.4 +/- 8.6 years. Giant aneurysms (> 2.5 cm) were present in 12 (60%) patients, large (1.5-2.5 cm)--in 5 (25%). Aneurysms of internal carotid artery were found in 8 cases. 1 female patient was operated on giant aneurysm of anterior cerebral--anterior communicating artery. In 4 (20%) cases significant alterations of blood flow were registered after clipping (> 25% according to initial), the changes were not visible. This allowed to correct the position of clips. In 2 surgeries ('low' paraclinoid aneurysms) the collateral flow was sufficient during temporary clipping, this allowed trapping of aneurysms with good neurological outcome. In 3 cases flowmeter was used to evaluate blood flow after extracranial-intracranial bypass. Ultrasonic flowmetry is a simple, reproducible and safe technique for intraoperative assessment of blood flow. Despite visual sufficiency of arteries flowmetry allows detection of surgically significant alterations of blood flow after clipping.