Comparison of hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment for internal carotid artery aneurysm

Abstract

OBJECTIVE De novo aneurysms generally develop in healthy vessels after parent artery occlusion for large internal carotid artery (ICA) aneurysm, possibly owing to increased hemodynamic stress in the remaining vessels. In recent years, there has been a shift toward flow diverter stent treatment. However, there is a lack of direct evidence and data that prove this change in hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment. The authors compared hemodynamic stress in healthy-side vessels before and after parent artery occlusion and flow diverter treatments. METHODS The authors included patients who underwent 3D cine phase-contrast MRI before and after large ICA aneurysm treatment. Spatially and temporally averaged volume flow rates and spatially averaged systolic wall shear stress (WSS) in healthy-side ICA distal to the posterior communicating artery (C1 segment according to Fisher’s classification) were measured before and after parent artery occlusion and flow diverter treatments. RESULTS Seventeen patients were included (5 patients in the parent artery occlusion group and 12 in the flow diverter group). At 1–2 months after treatment, median volume flow rate in healthy-side ICA increased from 5.36 ml/sec to 6.28 ml/sec (total increase 117%, p = 0.04) in the parent artery occlusion group and from 4.65 ml/sec to 4.93 ml/sec (total increase 106%, p = 0.02) in the flow diverter group. In the parent artery occlusion group, median WSS in the C1 segment of the healthy-side ICA increased from 3.91 Pa to 5.61 Pa (total increase 143%, p = 0.08); however, no significant increase was observed in the flow diverter group (4.29 Pa to 4.57 Pa [total increase 107%, p = 0.21]). CONCLUSIONS Postoperatively, volume flow rate and WSS in the C1 segment of the healthy-side ICA significantly increased in the parent artery occlusion group. Therefore, the parent artery occlusion group was more prone to de novo aneurysm than the flow diverter group.

The preoperative focal cerebral blood flow status may be associated with slow flow in the bypass graft after combined surgery for moyamoya disease

“…[26,34] Furthermore, as mentioned in a previous report, the flow on the ipsilateral side of the bypass is substantially affected by the wall shear stress that is directly related to the flow rate on the contralateral side. [30,34] is fact will complicate the estimation for patients with MMD, which is basically a bilateral disease. Similarly, the indirect revascularization effect that develops from the early postoperative period, which is peculiar to patients with MMD, makes it difficult to analyze the flow rate and pressure gradient by simply connecting the ECA system and the ICA system with a single graft.…”

“…[ 13 , 29 ] At the same time, regarding the graft flow in STA-MCA bypass, the pressure gradient similar to the previous vein graft has not been calculated and analyzed probably because the graft viability and sustainability are good, and the STA graft is thinner than the vein graft, making it difficult to verify the flow rate using MRA or CFD. [ 26 , 34 ] Furthermore, as mentioned in a previous report, the flow on the ipsilateral side of the bypass is substantially affected by the wall shear stress that is directly related to the flow rate on the contralateral side. [ 30 , 34 ]…”

“…[ 26 , 34 ] Furthermore, as mentioned in a previous report, the flow on the ipsilateral side of the bypass is substantially affected by the wall shear stress that is directly related to the flow rate on the contralateral side. [ 30 , 34 ]…”

Bibliometric and visual analysis of cerebral revascularization from 1999 to 2022

“…In recent years, with the continuous in-depth study of imaging technology and clinical understanding of carotid artery occlusion, an increasing number of clinical researchers have gradually realized that hemodynamic disorders play a crucial role in cerebral ischemia caused by carotid artery occlusion ( Tsukada et al, 2022 ). The study revealed that among patients with carotid artery occlusion receiving drug treatment ( Li et al, 2020 , 2022 ), the annual incidence of ipsilateral ischemic stroke was 3%, but the annual incidence of stroke increased to 10–20% in patients with severe cerebral hemodynamic disorders.…”