Editorial: Clip or coil? Six years of follow-up in BRAT
R. Loch Macdonald
The Barrow Ruptured Aneurysm Trial
Balloon-assisted Onyx embolization of cerebral single-channel pial arteriovenous fistulas
C. Benjamin Newman, Yin C. Hu, Cameron G. McDougall, and Felipe C. Albuquerque
Pial arteriovenous fistulas (AVFs) of the brain are rare vascular malformations associated with significant risks of hemorrhage and neurological deficit. Depending on their location and high-flow dynamics, these lesions can present treatment challenges for both endovascular and open cerebrovascular surgeons. The authors describe a novel endovascular treatment strategy that was used successfully to treat 2 pediatric patients with a pial AVF, and they discuss the technical nuances specific to their treatment strategy.
A single-channel high-flow pial AVF was diagnosed in 2 male patients (6 and 17 years of age). Both patients were treated with endovascular flow arrest using a highly conformable balloon followed by Onyx infusion for definitive closure of the fistula.
Neither patient suffered a complication as a result of the procedure. At the 6-month follow-up in both cases, the simple discontinuation of blood flow had resulted in durable obliteration of the fistula and stable or improved neurological function.
Onyx can be delivered successfully into high-flow lesions after flow arrest to allow a minimally invasive and durable treatment for pial AVFs.
Intraoperative spinal angiography
Wouter I. Schievink, A. Giancarlo Vishteh, Cameron G. McDougall, and Robert F. Spetzler
Object. The use of intraoperative angiography of the spine has become available to neurosurgeons as an adjunct in the management of complex spinal vascular malformations. These vascular malformations are rare, and the use of intraoperative angiography of the spine has not been well described. The authors report their recent experience with the use of this diagnostic modality.
Methods. Between 1995 and 1997, nine consecutive patients with type II or Type IV spinal arteriovenous malformations (AVMs) underwent intraoperative spinal angiography. The cervical spine was involved in three patients, the thoracic spine in five, and the thoracolumbar junction in one. In three patients, intraoperative spinal angiography revealed an unexpected finding (residual filling of the AVM). The results obtained using postoperative spinal angiography in all patients showed complete agreement with the intraoperative studies. No complications arose from obtaining the intraoperative spinal angiograms.
Conclusions. Intraoperative spinal angiography is technically feasible, can be performed safely, and has adequate resolution. It detects unexpected residual AVM in one-third of cases.
Editorial: Ipsilateral cerebral hemorrhage following deployment of the Pipeline Embolization Device
Kyle M. Fargen and Brian L. Hoh
Letter to the Editor: Barrow Ruptured Aneurysm Trial: 3-year results
Tim E. Darsaut and Jean Raymond
Letters to the Editor: The Barrow Ruptured Aneurysm Trial and International Subarachnoid Aneurysm Trial
Richard Kerr and Andrew Molyneux
Editorial: Arteriovenous malformations and embolization
Gregory J. Zipfel
Evolution of treatment and a detailed analysis of occlusion, recurrence, and clinical outcomes in an endovascular library of 260 dural arteriovenous fistulas
Bradley A. Gross, Felipe C. Albuquerque, Karam Moon, and Cameron G. McDougall
Many small series and technical reports chronicle the evolution of endovascular techniques for cranial dural arteriovenous fistulas (dAVFs) over the past 3 decades, but reports of large patient series are lacking. The authors provide a thorough analysis of clinical and angiographic outcomes across a large patient cohort.
The authors reviewed their endovascular database from January 1996 to September 2015 to identify patients harboring cranial dAVFs who were treated initially with endovascular approaches. They extracted demographic, presentation, angiographic, detailed treatment, and long-term follow-up data, and they evaluated natural history, initial angiographic occlusion, complications, recurrence, and symptomatic resolution rates.
Across a cohort of 251 patients with 260 distinct dAVFs, the overall initial angiographic occlusion rate was 70%; recurrence or occult residual lesions were seen on subsequent angiography in 3% of cases. The overall complication rate was 8%, with permanent neurological complications occurring in 3% of cases. Among 102 patients with dAVFs without cortical venous reflux, rates of resolution/improvement of pulsatile tinnitus and ocular symptoms were 79% and 78%, respectively. Following the introduction of Onyx during the latter half of the study period, the number of treated dAVFs doubled; the initial angiographic occlusion rate increased significantly from 60% before the use of Onyx to 76% after (p = 0.01). In addition, during the latter period compared with the pre-Onyx period, the rate of dAVFs obliterated via a transarterial-only approach was significantly greater (43% vs 23%, p = 0.002), as was the number of dAVFs obliterated via a single arterial pedicle (29% vs 11%, p = 0.002).
Overall, in the Onyx era, the rate of initial angiographic occlusion was approximately 80%, as was the rate of meaningful clinical improvement in tinnitus and/or ocular symptoms after initial endovascular treatment of cranial dAVFs.
The evolution of endovascular treatment for intracranial arteriovenous malformations
Ruth E. Bristol, Felipe C. Albuquerque, and Cameron G. McDougall
✓ Endovascular therapy for arteriovenous malformations (AVMs) remains a relatively new approach. Beginning in the 1960s with the use of flow-directed techniques for selective embolization, hemodynamic alterations have been used to treat these lesions. In every aspect of treatment, technological advances, including catheters, embolic materials, angiography suites, and pharmacological agents, have improved outcomes while lowering the risk to patients.
In this article, the authors review the technical evolution of endovascular AVM therapy. Developments in embolic materials, beginning with foreign bodies and autografts and continuing through to highly engineered contemporary substances, are discussed. Finally, changes in treatment paradigms that have occurred over the years are traced. Within neurosurgery, this specialty has shown some of the fastest growth and development in recent decades. As minimally invasive approaches are embraced in all areas of medicine, it is clear that this treatment modality will continue to be refined.