Effect of Adventitial Dissection of Superficial Temporal Artery on the Outcome of Superficial Temporal Artery-Middle Cerebral Artery Bypass in Moyamoya Disease

Combination of intraoperative indocyanine green video-angiography FLOW 800 and computed tomography perfusion to assess the risk of cerebral hyperperfusion syndrome in chronic internal carotid artery occlusion patients after revascularization surgery

Background and purpose

To study the changes of corticocerebral hemodynamics in surgical area and postoperative hyperperfusion syndrome in patients with chronic internal carotid artery occlusion (CICAO) by intraoperative indocyanine green videoangiography (ICGA)-FLOW 800 and CT perfusion after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass surgery.

Methods

From October 2019 to January 2021, 77 patients diagnosed with CICAO underwent direct bypass surgery at Huadong hospital (affiliated with Fudan University) were enrolled. Regions of interest (ROIs) at STA, proximal MCA (PMCA), distal MCA (DMCA), cortical blood capillary (CBC), and cortical vein (CV) were identified after anastomosis by ICGV-FLOW 800 including peak fluorescence intensity (PFI), time to peak (TTP), and area under the time curve (AUC) of fluorescence intensity. All patients underwent perfusion-weighted CT before bypass surgery and those patients with HPS were verified by CTP after bypass.

Results

14 patients with HPS were verified by perfusion-weighted CT after bypass. In HPS group, the AUCTTP of DMCA was significantly larger (T = -3.301, p = 0.004) and TTP of CBC was shorter (T = -2.929, p = 0.005) than patients in non-HPS group. The larger AUCTTP of DMCA (OR = 3.024, 95%CI 1.390-6.578, p = 0.0050) was an independent risk factor by further multivariate logistic regression analysis.

Conclusion

The hemodynamic changes of cortical vessels during STA-MCA bypass surgery could be recorded accurately by ICGV-FLOW 800. Furthermore, the increased AUCTTP of DMCA and shorter TTP of CBC may be potential risk factors of HPS.

Intraoperative local hemodynamic quantitative analysis of direct revascularization in patients with moyamoya disease

Direct bypass surgery improves blood flow in patients with moyamoya disease (MMD) as well as causes local flow relocation and disturbance. This study aimed to describe the characteristics and changes of quantitative blood flow in MMD patients. Sixty-four consecutive MMD patients (67 hemispheres) who underwent STA-MCA anastomosis between August 2013 and September 2017 were included in this study. Intraoperative blood flow of superficial temporal artery and middle cerebral artery was measured with a noninvasive, ultrasound flowprobe, before and after the bypass. All data were collected prospectively. Before the bypass, 67 hemispheres were measured and 45 hemispheres acquired post-bypass measurements. Thirty-three (49.3%) had anterograde flow and 34 (50.7%) had retrograde. Retrograde blood flow was significantly higher than anterograde blood flow in MCA-M4 section (3.71 ± 2.78 ml/min vs 2.39 ± 1.71 ml/min, P = 0.023). Thirty-eight (56.7%) patients had local cerebrovascular reactivity, whereas 29 (43.3%) lost it. After bypass, blood flow was changed into three patterns: anterograde flow (1, 2.2%), retrograde flow (3, 6.7%), and bi-direction flow (41, 91.1%). Flow of M4 was significantly improved in both proximal (13.64 ± 9.16 vs 3.28 ± 2.57, P < 0.001) and distal (7.17 ± 7.21 vs 3.28 ± 2.57, P = 0.002) sides to the bypass. Postoperative infarctions occurred in 4 (8.9%) patients. All postoperative infarctions (n = 4) happened in those patients who did not have change of flow direction in M4 section distal to the bypass (P = 0.040). Direct bypass surgery improves local blood flow after bypass surgery in both sides of the anastomosis. Flow direction was usually changed after the surgery into a bi-direction pattern: anterograde flow in M4 distal to the bypass, and retrograde flow in M4 proximal to the bypass. Proximal side acquired around 5.4 times of flow than the distal side. Patients with change of flow direction in distal M4 were related with lower risks of postoperative infarctions.

Long-Term Patency and Final Structure After Superficial Temporal Artery-Middle Cerebral Artery Bypass Surgery: A Retrospective Study

OBJECTIVE

To investigate long-term bypass patency and final structure for patients who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) bypass.

METHODS

This study retrospectively evaluated 20 patients who underwent STA-MCA bypass and had 2-year follow-up with cerebral angiography. Patients were divided into internal carotid artery occlusion (n = 11) and MCA occlusion or stenosis (n = 9) groups, and diagnosis was either arteriosclerotic (n = 14) or nonarteriosclerotic (n = 6) disease. Final bypass formation was examined with cerebral angiography at 2 years postoperatively. Diameters of the STA, middle meningeal artery (MMA), and deep temporal artery (DTA) were measured at preoperative angiography and at 2-year follow-up.

RESULTS

No significant differences in STA, MMA, and DTA diameters were reported between the internal carotid artery versus MCA group. For patients with arteriosclerotic disease, thicker STA diameters were noted on preoperative angiography. For patients with nonarteriosclerotic disease, MMA and DTA dilatation was noted on 2-year follow-up imaging. For patients with arteriosclerotic disease, all direct bypasses were patent at 2 years. For patients with nonarteriosclerotic disease, remarkable angiogenesis was demonstrated.

CONCLUSIONS

Long-term patency of a direct bypass may be correlated with arteriosclerotic or nonarteriosclerotic etiology. An indirect bypass route may develop in patients with nonarteriosclerotic disease; therefore, it is important to create a foundation for an indirect bypass with MMA and DTA preservation during craniotomy. In 2 patients with nonarteriosclerotic disease, STA remained the primary bypass foundation; however, the technique resembled novel angiogenesis after encephaloduroarteriosynangiosis and not direct STA-MCA bypass. Therefore, final bypass structure might be affected by disease etiology.

Asymmetric lenticulostriate arteries in patients with moyamoya disease presenting with movement disorder: three new cases

OBJECTIVE

Unilateral movement disorder associated with moyamoya disease is a rare finding and the mechanism remains to be fully elucidated. Theories postulated include contralateral cerebral ischemic or hemorrhagic lesions, and/or hypoperfusion. However, few studies have reported such patients without contralateral lesions nor hypoperfusion. This study aimed to explore the potential mechanism of those who had neither contralateral cerebral lesions nor hypoperfusion.

METHODS

Neuroradiological features of lenticulostriate arteries in three cases with unilateral movement disorder associated with moyamoya disease who had neither contralateral lesions nor hypoperfusion were mainly analyzed.

RESULTS

Angiography and 3 T black-blood T1-weighted intracranial vessel wall imaging both demonstrated a significant asymmetry between bilateral lenticulostriate arteries qualitatively and quantitatively on admission. After one-year follow-up, two patients' vessel wall imaging indicated that the asymmetry diminished, and the symptoms spontaneously resolved.

CONCLUSION

This report demonstrated that patients with moyamoya disease with unilateral movement disorder who had neither contralateral lesions nor hypoperfusion may be related to the asymmetry between bilateral lenticulostriate arteries through basal ganglia.

Dissection of the Superficial Temporal Artery: Significance and Performance with Bipolar Forceps

BACKGROUND

Adequate bypass harvesting of the superficial temporal artery (STA) is a standard procedure for every neurosurgeon, so mastery of techniques for its management and care is mandatory.

METHODS

Here, we report the effectiveness of using the bipolar forceps as a novel procedure.

RESULTS

This procedure improves safety, efficiency, and bleeding compared to the usual dissection.

CONCLUSIONS

In cases requiring an STA donor, this technique may be as useful as the traditional method and could become part of the neurosurgeon's armamentarium.