Quantitative angiographic haemodynamic evaluation of bypasses for complex aneurysms: a preliminary study

Area of Science:

• Neurosurgery
• Vascular Surgery
• Neuroradiology

Background:

• Open microsurgery with bypass is crucial for complex aneurysms.
• Predicting insufficient flow-related stroke (IRS) after these procedures remains challenging.
• The role of arterial anatomy versus quantitative blood flow in IRS risk is unclear.

Purpose of the Study:

• To identify risk factors for IRS in patients undergoing open microsurgery with bypass for complex internal carotid artery aneurysms.
• To evaluate the predictive value of arterial anatomy and quantitative blood flow measurements for IRS.
• To determine if the recipient/donor flow index (RDFI) or recipient/donor diameter index (RDDI) can predict IRS.

Main Methods:

• Retrospective review of patients with complex aneurysms undergoing bypass surgery.
• Preoperative evaluation of recipient/donor flow index (RDFI) using quantitative angiography.
• Calculation of recipient/donor diameter index (RDDI) based on arterial measurements.
• Assessment of the association between RDFI, RDDI, and the incidence of postoperative IRS.

Main Results:

• IRS occurred in 60% of analyzed patients (12/20).
• Patients with postoperative IRS exhibited a significantly higher RDFI compared to those without IRS (p<0.001).
• An RDFI greater than 2.3 was strongly associated with an increased likelihood of developing IRS (p<0.001).
• RDDI did not show a significant difference between groups with and without IRS (p=0.905).

Conclusions:

• Quantitative digital subtraction angiography allows for preoperative assessment of cerebral blood volume.
• RDFI > 2.3 is a significant predictor of postoperative IRS, outperforming RDDI.
• Preoperative RDFI evaluation aids in optimizing treatment strategies to mitigate IRS risk.