Quantitative Angiographic Hemodynamic Evaluation After Revascularization Surgery for Moyamoya Disease

Abstract

The corresponding hemodynamic changes of the internal carotid artery (ICA) after the revascularization surgery for moyamoya disease (MMD) remain unclear. The aim of this study was to analyze the hemodynamic changes of the ipsilateral ICA after the combined direct and indirect extracranial-intracranial (EC-IC) bypass. MMD patients undergoing combined EC-IC bypass were retrospectively reviewed. The mean transit time (MTT) of ICA was evaluated by color-coding angiography before revascularization and at follow-up. The MTT defined as the blood transit time between the end of cervical portion (C1) and the C7 segment of ICA. The clinical prognosis was assessed with Matsushima grading system, moyamoya vessel reduction system, and modified Rankin Scale (mRS). The correlation between hemodynamic parameter and prognosis was analyzed. Subgroup analysis was conducted between different presentations and different ages. Fifty-one patients were identified and the mean imaging follow-up interval was 5.5 months. The ICA-MTT was increased after the combined revascularization (P < 0.001) compared with contralateral ICA. Faster preoperative ICA-MTT was significantly associated with improved mRS in the ischemic group (P = 0.05). The increased ICA-MTT was significantly associated with favorable neoangiogenesis (P = 0.04), moyamoya vessel reduction (> 50%) (P = 0.023), and improved mRS score (P = 0.008). In subgroup analysis, the correlation in the ischemic subgroup and adult subgroup remained significant. In this cohort, the ICA-MTT increased after the combined EC-IC bypass, and there was a positive correlation between the increased blood transit time and favorable outcomes. Color-coding DSA proved to be useful as a quantitative and serial method to monitor postoperative courses after revascularization in MMD.

Preliminary Study on the Application of Ultrahigh Field Magnetic Resonance in Moyamoya Disease

“…A previous study revealed that the presence of the brush sign was significantly associated with a poor outcome in patients with ischemic stroke [ 25 ]. With UHF MRI, the conspicuity of deep medullary vein increased, which enabled it to sensitively anticipate the extent of the impaired perfusion in MMD without the need to perform hemodynamic examinations, such as CTP, ASL, SPECT, or PET [ 26 , 27 ]. The application of the SWI sequence in high-field MRI in the assessment of hemodynamics of patients with MMD still needs further research.…”

Delayed Anastomotic Occlusion after Direct Revascularization in Adult Hemorrhagic Moyamoya Disease

“…Dilated AChA-PCoA was reported to be present in 41.7–71.9% of hemorrhagic MMD patients [ 16 , 35 , 36 , 37 ], and 23.2–70.1% of them would be improved after revascularization [ 27 , 34 , 38 ]. This change in vascular remodeling may be related to ipsilateral ICA disuse occlusion caused by extracranial-intracranial (EC-IC) blood flow conversion after revascularization [ 39 , 40 ]. In this study, 80.3% of patients observed improvement in dilated AChA-PCoA after direct revascularization, and the improvement of dilated AChA-PCoA has no significant correlation with graft patency.…”

“…In this study, 80.3% of patients observed improvement in dilated AChA-PCoA after direct revascularization, and the improvement of dilated AChA-PCoA has no significant correlation with graft patency. Neoangiogenesis was recognized as the most intuitive angiographic prognostic indicator after revascularization in MMD patients [ 19 , 39 ]. Previous studies reported that 64.8–85.3% of hemorrhagic MMD patients could achieve satisfactory neoangiogenesis (Matsushima Level A, B) after direct/combined bypass [ 12 , 13 , 34 ].…”

Imaging methods for surgical revascularization in patients with moyamoya disease: an updated review

“…Quantitative color-coded parametric DSA (QDSA, Syngo iFlow) is an emerging DSA technique which provides objective perfusion parameters like time-to-peak (TTP), mean transit time (MTT), and ratios of area under the curve (AUC ratio) to assess hemodynamic changes of a certain artery after bypass surgery. Although it does not provide information on cerebral parenchyma perfusion, it is useful for measuring blood supply from the internal and external carotid artery systems [8,9]. However, DSA is not recommended for pediatric patients or patients in poor conditions, due to its invasiveness, time consumption, and need for anesthesia.…”