Microsurgery for cerebral arteriovenous malformations: subgroup outcomes in a consecutive series of 288 cases

Recent Trends in Neuro-endovascular Treatment for Acute Ischemic Stroke, Cerebral Aneurysms, Carotid Stenosis, and Brain Arteriovenous Malformations

The efficacy of mechanical thrombectomy with stent retrievers for emergent large vessel occlusion has been proved by randomized trials. Mechanical thrombectomy is increasingly being adopted in Japan since stent retrievers were first approved in 2014. An urgent clinical task is to offer structured systems of care to provide this treatment in a timely fashion to all patients with emergent large vessel occlusion. Treatment with flow-diverting stents is currently a preferred treatment option worldwide for large and giant unruptured aneurysms. Initial studies reported high rates of complete aneurysm occlusion, even in large and giant aneurysms, without delayed aneurysmal recanalization and/or growth. The Pipeline Embolic Device is a flow diverter recently approved in Japan for the treatment of large and giant wide-neck unruptured aneurysms in the internal carotid artery, from the petrous to superior hypophyseal segments. Carotid artery stenting is the preferred treatment approach for carotid stenosis in Japan, whereas it remains an alternative for carotid endarterectomy in Europe and the United States. Carotid artery stenting with embolic protection and plaque imaging is effective in achieving favorable outcomes. The design and conclusions of a randomized trial of unruptured brain arteriovenous malformations (ARUBA) trial, which compared medical management alone and medical management with interventional therapy in patients with an unruptured arteriovenous brain malformation, are controversial. However, the annual bleeding rate (2.2%) of the medical management group obtained from this study is worthy of consideration when deciding treatment strategy.

"Dirty coagulation" technique as an alternative to microclips for control of bleeding from deep feeders during brain arteriovenous malformation surgery

BACKGROUND

Meticulous haemostasis is one of the most important factors during microneurosurgical resection of brain arteriovenous malformation (AVM). Controlling major arterial feeders and draining veins with clips and bipolar coagulation are well-established techniques, while managing with bleeding from deep tiny vessels still proves to be challenging. This technical note describes a technique used by the senior author in AVM surgery for last 20 years in dealing with the issue highlighted.

METHOD

"Dirty coagulation" is a technique of bipolar coagulation of small feeders carried out together with a thin layer of brain tissue that surrounds these fragile vessels. The senior author uses this technique for achieving permanent haemostasis predominantly in large and/or deep-seated AVMs. To illustrate the efficacy of this technique, we retrospectively reviewed the outcome of Spetzler-Martin (SM) grade III-V AVMs resected by the senior author over the last 5 years (2010-2015).

RESULTS

Thirty-five cases of AVM surgeries (14 SM grade III, 15 SM grade IV and 6 SM grade V) in this 5-year period were analysed. No postoperative intracranial haemorrhage was encountered as a result of bleeding from the deep feeders. Postoperative angiograms showed complete resection of all AVMs, except in two cases (SM grade V and grade III).

CONCLUSIONS

"Dirty coagulation" provides an effective way to secure haemostasis from deep tiny feeders. This cost-effective method could be successfully used for achieving permanent haemostasis and thereby decreasing postoperative haemorrhage in AVM surgery.