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

Yoshio Araki; Kinya Yokoyama; Kenji Uda; Fumiaki Kanamori; Takashi Mamiya; Kai Takayanagi; Kazuki Ishii; Kazunori Shintai; Masahiro Nishihori; Tetsuya Tsukada; Kazuhito Takeuchi; Kuniaki Tanahashi; Yuichi Nagata; Yusuke Nishimura; Takafumi Tanei; Yoshitaka Nagashima; Shinsuke Muraoka; Takashi Izumi; Yukio Seki; Ryuta Saito

doi:10.25259/SNI_772_2022

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

Surg Neurol Int. 2022 Nov 4:13:511. doi: 10.25259/SNI_772_2022. eCollection 2022.

Authors

Yoshio Araki¹, Kinya Yokoyama¹, Kenji Uda¹, Fumiaki Kanamori¹, Takashi Mamiya¹, Kai Takayanagi¹, Kazuki Ishii¹, Kazunori Shintai², Masahiro Nishihori¹, Tetsuya Tsukada², Kazuhito Takeuchi¹, Kuniaki Tanahashi¹, Yuichi Nagata¹, Yusuke Nishimura¹, Takafumi Tanei¹, Yoshitaka Nagashima¹, Shinsuke Muraoka³, Takashi Izumi¹, Yukio Seki², Ryuta Saito¹

Affiliations

¹ Department of Neurosurgery, Nagoya University, Nagoya, Japan.
² Department of Neurosurgery, Japanese Red Cross Aichi Medical Center Nagoya Daini Hospital, Nagoya, Japan.
³ Department of Neurosurgery, Kariya Toyota General Hospital, Kariya, Japan.

Abstract

Background: The aim of this study was to investigate the association between early postoperative slow flow in bypass grafts and preoperative focal cerebral blood flow (CBF) in patients who underwent combined surgery for moyamoya disease (MMD).

Methods: The subjects were 18 patients (22 surgeries) who underwent single photon emission computed tomography (SPECT) before surgery. The CBF value of the middle cerebral artery territory was extracted from the SPECT data, and the value relative to the ipsilateral cerebellar CBF (relative CBF, or RCBF) was calculated. The association between RCBF and early postoperative slow flow in the bypass graft was investigated. In addition, the correlation between the revascularization effect and preoperative RCBF was analyzed.

Results: In four of 22 surgeries (18.2%), slow flow in the bypass graft was identified in the early postoperative period. Preoperative RCBF in the slow flow and patent groups was 0.86 ± 0.15 and 0.87 ± 0.15, respectively, with no significant difference (P = 0.72). The signal intensity of four slow-flowed bypasses was improved in all cases on magnetic resonance angiography images captured during the chronic phase (mean of 3.3 months postoperatively). The revascularization scores were 2 ± 0.82 and 2.1 ± 0.68 in the slow flow and patent groups, respectively, and did not differ significantly (P = 0.78). A significant correlation was not observed between preoperative RCBF and the revascularization effect.

Conclusion: No significant association was observed between preoperative RCBF and early postoperative slow flow in bypass grafts in patients with MMD undergoing combined surgery. Given the high rate of improved depiction of slow-flowed bypass in the chronic postoperative phase, the conceptual significance of an opportune surgical intervention is to maintain CBF by supporting the patient's own intracranial-extracranial conversion function.

Keywords: Cerebral blood flow; Combined revascularization; Moyamoya disease; Recanalization; Slow-flowed direct bypass.