Intraoperative tracking of tissue perfusion during cerebral aneurysm surgery with laser speckle contrast imaging: insights beyond standard intraoperative neuromonitoring for detecting ischemia

SignificanceIntraoperative cerebral ischemia is a critical complication that can arise during cerebral aneurysm clipping surgery. Although intraoperative neuromonitoring (IONM) can detect resulting functional deficits, these alerts may occur minutes after the initial ischemic event.AimWe aimed to demonstrate the clinical utility of laser speckle contrast imaging (LSCI) for continuous, real-time monitoring of cerebral blood flow (CBF) during aneurysm surgery.ApproachIn this case study, a 67-year-old female underwent a craniotomy for a left-sided cerebral aneurysm. A microscope-integrated LSCI system was used to continuously monitor cortical perfusion. After surgery, LSCI data were correlated with IONM alerts, indocyanine green angiography (ICGA), and surgical events, including an ischemic period following clip placement. A paired t-test, mixed effects model, and changepoint analysis were used to compare mean perfusion between the pre-ischemic and ischemic periods across seven regions of interest (ROIs) on the cortical surface.ResultsLSCI detected a widespread drop in cortical perfusion immediately following the application of an aneurysm clip. This perfusion deficit was detected by LSCI ∼8 min before the corresponding IONM alert. During the ischemic period, blood flow decreased across six of the seven ROIs, with reductions ranging from 7.9% to 28.0%. The overall decrease in perfusion from the pre-ischemic to the ischemic period was statistically significant (p<0.0001).ConclusionsLSCI can provide continuous imaging of tissue perfusion during surgery, enabling the detection of developing ischemia before functional deficits may be evident on IONM. The ability of LSCI to track tissue perfusion changes highlights its potential as a valuable complementary tool for enhancing surgical safety alongside IONM and ICGA.