Occlusion of M1 segment after superficial temporal artery-middle cerebral artery bypass in a giant M1 aneurysm with Onyx-34 injected via a double-lumen balloon under balloon inflation

Is STA really a low‐flow graft? A quantitative ultrasonographic study of the flow of STA for cerebral revascularization in MMD patients

OBJECTIVE

Direct revascularization remains an important tool in the treatment of patients with Moyamoya disease (MMD). The superficial temporal artery (STA) is the most commonly used donor vessel for direct bypass, and an STA graft has traditionally been considered a low-flow graft for flow augmentation. This study aimed to quantitatively evaluate the blood flow of the STA after direct revascularization.

METHODS

All direct revascularization procedures performed between 2018 and 2021 by one experienced neurosurgeon were screened. Quantitative ultrasound was used to measure the flow data of the patient's bilateral parietal branch of the STA(STA-PB), the bilateral frontal branch of the STA(STA-FB), and the left radial artery. Data on the patients' basic information, Suzuki grade, Matsushima type, anastomosis type, and blood biochemical parameters were collected and analyzed using univariate and multivariate models. An MBC Scale scoring system was proposed to evaluate the recipient artery network of the middle cerebral artery (MCA) tree. The relationship between MBC Scale score and STA graft flow was statistically analyzed.

RESULTS

In total, 81 patients (43 males and 38 females) successfully underwent STA-MCA bypass and were included in this study. The mean flow rates in the STA-PB graft on 1 day preoperatively, 1 day postoperatively, 7 days postoperatively, and >6 months postoperatively (long-term) were 10.81, 116.74, 118.44, and 56.20 mL/min respectively. Intraoperative graft patency was confirmed in all patients. Comparing the preoperative and all postoperative time points, the STA-PB flow rates were statistically significant (p < 0.001). The MCA-C score was significantly associated with postoperative flow rate on day 1 (p = 0.007).

CONCLUSION

The STA is a useful donor artery for direct revascularization inpatients with MMD and can provide sufficient blood supply to the ischemic cerebral territory.

A Hybrid Strategy for Patients With Complex Cerebral Aneurysm: STA-MCA Bypass in Combination With Endovascular Embolization

Objective: This work aims to present our experience of patients with complex cerebral aneurysm treated with a hybrid approach: superficial temporal artery–middle cerebral artery (STA–MCA) bypass in combination with endovascular exclusion of the aneurysm.

Method: Patients with aneurysms deemed unclippable and uncoilable were included. All patients were treated with a hybrid approach. After STA–MCA bypass, the parent artery was temporarily occluded. If the intraoperative motor evoked potential (MEP) and somatosensory evoked potential (SEP) waveforms remain normal and last for 30 min, the aneurysm and te parent artery will be embolized permanently with detachable balloons or coils.

Results: A total of 20 patients with 22 aneurysms were included in this study. There were 13 women and 7 men, with an average age of 42.5 years. Intraoperative angiography showed the good patency of all the STA grafts, and neither SEP nor MEP abnormalities were detected. After the parent artery and the aneurysm were occluded, the intraoperative angiography showed an immediately successful exclusion of the aneurysm in 20 aneurysms and immediate contrast stasis in two. All patients recovered uneventfully without ischemic or hemorrhagic complication. Angiography at 6-month follow-up showed the total obliteration in 20 aneurysms. Two aneurysms showed residuals and were recoiled. All STA grafts showed a good patency, and the mean graft flow was 124.2 ml/min.

Conclusion: STA–MCA bypass in combination with endovascular exclusion is an appropriate option for patients with complex cerebral aneurysms that are not amenable to direct surgical clipping or endovascular embolization.

Injection of N‑butyl Cyanoacrylate Through a Dual-Lumen Balloon for Embolization of High-flow Intranidal Fistulas in Brain Arteriovenous Malformations: Technical Note

PURPOSE

N-butyl cyanoacrylate (NBCA) glue is a valuable liquid embolic agent for the endovascular treatment of brain arteriovenous malformations (BAVM). The use of NBCA carries a risk of embolic agent reflux and distal migration with ensuing possibility of venous drainage compromise. The aim of this technical note is to describe a single center case series of high-flow intranidal fistulas embolized though a dual lumen balloon under local flow-arrest conditions.

METHODS

This article presents a retrospective description of a case series including five NBCA injections through a dual lumen balloon performed by a single operator in three patients with BAVM. Demographic, clinical, imaging and procedure-related data are reported.

RESULTS

The three patients presented with ruptured BAVMs. Of the patients, one underwent proximal flow-related ruptured aneurysm coiling before planned BAVM embolization. In the three patients, staged BAVM embolization as a first line treatment was decided. Preliminary embolization of high-flow BAVM fistulas by NBCA using a dual lumen balloon under local flow-arrest conditions was performed and five separate injections were carried out without any complications. No balloon entrapment or rupture was observed.

CONCLUSION

High-flow BAVM fistulas can be treated with NBCA embolization using a dual lumen balloon under local flow-arrest conditions.

Double-lumen balloon for Onyx® embolization via extracranial arteries in transverse sigmoid dural arteriovenous fistulas: initial experience

Transverse-sigmoid dural arteriovenous fistulas (TS DAVFs) can be challenging to treat by endovascular means. Indeed, a total cure of the fistula can only be achieved when complete occlusion of the fistulous point(s) is obtained by penetration of the embolic agent. However, in some cases, especially for transosseous branches from extracranial arteries like the occipital artery (OcA) or the superficial temporal artery (STA), such penetration is usually poor, leading to major proximal reflux and incomplete fistula obliteration. We present three cases of embolization in two patients with TS DAVF through the OcA and/or the STA with Onyx® using a double-lumen balloon (Microvention, Tustin, CA, USA). This technique allows the penetration of the embolic agent in the transosseous branches by forming a counter-pressure with the inflated balloon. This technique may be useful to achieve complete occlusion of TS DAVFs by endovascular means.