ABSTRACT
Introduction: Adequate blood flow monitoring in cerebral aneurysm surgery is still a challenge today. Even though pre- and postoperative care is frequently emphasized, intraoperative monitoring is often forgotten. Case description: The authors report the clipping of a giant internal carotid artery aneurysm; however, after the frontal lobe retractor was released, the aneurysm clips rotated and flow reduction could be detected via continuous transcranial Doppler ultrasonography. Ischaemia was avoided by repositioning the clips with gelatin sponge and cellulose hemostat. Discussion: Somatosensory evoked potential recording, intraoperative angiography and microvascular and transcranial Doppler are the most popular methods for intraoperative cerebral blood flow monitoring; however, each of methods has its own advantages and disadvantages. None of them can perfectly measure cerebral blood flow, detect insufficient aneurysm clipping and 2 avoid stenoses; costs, the additional surgical time and potential morbidity must also be considered. Ideally, intraoperative monitoring would be prolonged to the final stages of the surgical procedure so that unusual causes of ischemia such as clip rotation may be avoided. Perhaps new monitoring methods will overcome these difficulties; today, the .perfect. monitoring method should be tailored for each patient and the vessels involved.