Objective:To explore the value of intraoperative multimodal monitoring in superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery in evaluating hemodynamic parameters and blood-brain barrier disruption, as well as their correlations with postoperative perfusion changes.Methods:A retrospective case series study was performed; 60 patients with ischemic cerebrovascular diseases admitted to Department of Neurosurgery, Lianyungang Clinical Medical College of Nanjing Medical University (Lianyungang First People's Hospital) from March 2023 to October 2024 were selected, including 17 patients with moyamoya disease and 43 patients with chronic internal carotid artery occlusion and/or chronic symptomatic MCA stenosis/occlusion. All patients were confirmed by CTA or DSA and underwent STA-MCA M4 segment bypass surgery. Intraoperatively, microvascular Doppler ultrasound (MDU), sodium fluorescein angiography, and indocyanine green angiography combined with Flow800 (ICG-Flow800) were used to monitor the blood-brain barrier disruption grade, as well as the peak systolic velocity (PSV) and blood flow direction of the STA and recipient artery before and after arterial anastomosis. Cerebral blood perfusion improvement was reexamined by CT perfusion (CTP) 7 days and 1 month after surgery. These 60 patients were divided into a group with blood flow into the sylvian fissure (inflow group, n=27) and a group with blood flow out of the sylvian fissure (outflow group, n=33) according to the direction of recipient artery blood flow before arterial anastomosis, and further subdivided into subgroups with PSV≤10 cm/s and >10 cm/s based on the recipient artery PSV. Clinical and imaging data of these patients were collected and analyzed as follows: (1) CTP parameters such as cerebral blood volume, cerebral blood flow, mean transit time, and time to peak before surgery, 7 days after surgery, and 1 month after surgery were compared; (2) differences between the recipient artery PSV before arterial anastomosis and recipient artery exiting sylvian fissure velocity (RA.EXV) or recipient artery entering sylvian fissure velocity (RA.ESV) of the recipient artery after anastomosis were compared; (3) differences in ICG-Flow800 fluorescence intensity curve parameters such as delay time, rise time, curve slope, time to peak, and maximum fluorescence intensity of the cerebral surface veins before and after arterial anastomosis were compared; (4) spearman rank correlation was used to analyze the correlation of recipient artery PSV before arterial anastomosis with preoperative CTP parameters in all patients, the correlations of RA.ESV in the inflow group or RA.EXV in the outflow group with CTP parameters 7 days after surgery, and the correlations of blood-brain barrier disruption grade with preoperative CTP parameters, recipient artery PSV before arterial anastomosis, and RA.ESV or RA.EXV after arterial anastomosis in all patients. Results:(1) The blood flow direction of all recipient arteries became bidirectional after surgery. Cerebral blood perfusion improved to varying degrees after surgery: the mean transit time 7 days and 1 month after surgery, and cerebral blood flow 1 month after surgery were significantly higher compared with those before surgery ( P<0.05). (2) Regardless of the blood flow direction (into or out of the sylvian fissure), the RA.ESV or RA.EXV after anastomosis was significantly higher than the recipient artery PSV before anastomosis when the recipient artery PSV≤10 cm/s ( P<0.05). (3) For all patients, the ICG-Flow800 fluorescent intensity curve parameters of cerebral surface veins after anastomosis improved significantly compared with that before anastomosis ( P<0.05). (4) Preoperative recipient artery PSV was positively correlated with preoperative CBF in all patients ( rs=0.445, P=0.020). In the inflow group, postoperative RA.ESV was positively correlated with Tmax 7 days after surgery ( rs=0.490, P=0.009). The blood-brain barrier disruption grade was positively correlated with preoperative Tmax in all patients ( rs=0.478, P=0.012). Conclusion:Intraoperative multimodal monitoring in STA-MCA bypass surgery can provide surgeons with detailed hemodynamic parameters and blood-brain barrier disruption data, enabling real-time evaluation of surgical outcomes to optimize operative decision-making.

Objective:To explore the value of intraoperative multimodal monitoring in superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery in evaluating hemodynamic parameters and blood-brain barrier disruption, as well as their correlations with postoperative perfusion changes.Methods:A retrospective case series study was performed; 60 patients with ischemic cerebrovascular diseases admitted to Department of Neurosurgery, Lianyungang Clinical Medical College of Nanjing Medical University (Lianyungang First People's Hospital) from March 2023 to October 2024 were selected, including 17 patients with moyamoya disease and 43 patients with chronic internal carotid artery occlusion and/or chronic symptomatic MCA stenosis/occlusion. All patients were confirmed by CTA or DSA and underwent STA-MCA M4 segment bypass surgery. Intraoperatively, microvascular Doppler ultrasound (MDU), sodium fluorescein angiography, and indocyanine green angiography combined with Flow800 (ICG-Flow800) were used to monitor the blood-brain barrier disruption grade, as well as the peak systolic velocity (PSV) and blood flow direction of the STA and recipient artery before and after arterial anastomosis. Cerebral blood perfusion improvement was reexamined by CT perfusion (CTP) 7 days and 1 month after surgery. These 60 patients were divided into a group with blood flow into the sylvian fissure (inflow group, n=27) and a group with blood flow out of the sylvian fissure (outflow group, n=33) according to the direction of recipient artery blood flow before arterial anastomosis, and further subdivided into subgroups with PSV≤10 cm/s and >10 cm/s based on the recipient artery PSV. Clinical and imaging data of these patients were collected and analyzed as follows: (1) CTP parameters such as cerebral blood volume, cerebral blood flow, mean transit time, and time to peak before surgery, 7 days after surgery, and 1 month after surgery were compared; (2) differences between the recipient artery PSV before arterial anastomosis and recipient artery exiting sylvian fissure velocity (RA.EXV) or recipient artery entering sylvian fissure velocity (RA.ESV) of the recipient artery after anastomosis were compared; (3) differences in ICG-Flow800 fluorescence intensity curve parameters such as delay time, rise time, curve slope, time to peak, and maximum fluorescence intensity of the cerebral surface veins before and after arterial anastomosis were compared; (4) spearman rank correlation was used to analyze the correlation of recipient artery PSV before arterial anastomosis with preoperative CTP parameters in all patients, the correlations of RA.ESV in the inflow group or RA.EXV in the outflow group with CTP parameters 7 days after surgery, and the correlations of blood-brain barrier disruption grade with preoperative CTP parameters, recipient artery PSV before arterial anastomosis, and RA.ESV or RA.EXV after arterial anastomosis in all patients. Results:(1) The blood flow direction of all recipient arteries became bidirectional after surgery. Cerebral blood perfusion improved to varying degrees after surgery: the mean transit time 7 days and 1 month after surgery, and cerebral blood flow 1 month after surgery were significantly higher compared with those before surgery ( P<0.05). (2) Regardless of the blood flow direction (into or out of the sylvian fissure), the RA.ESV or RA.EXV after anastomosis was significantly higher than the recipient artery PSV before anastomosis when the recipient artery PSV≤10 cm/s ( P<0.05). (3) For all patients, the ICG-Flow800 fluorescent intensity curve parameters of cerebral surface veins after anastomosis improved significantly compared with that before anastomosis ( P<0.05). (4) Preoperative recipient artery PSV was positively correlated with preoperative CBF in all patients ( rs=0.445, P=0.020). In the inflow group, postoperative RA.ESV was positively correlated with Tmax 7 days after surgery ( rs=0.490, P=0.009). The blood-brain barrier disruption grade was positively correlated with preoperative Tmax in all patients ( rs=0.478, P=0.012). Conclusion:Intraoperative multimodal monitoring in STA-MCA bypass surgery can provide surgeons with detailed hemodynamic parameters and blood-brain barrier disruption data, enabling real-time evaluation of surgical outcomes to optimize operative decision-making.