R. Loch Macdonald
Gregory J. Zipfel
Ignacio Arrese and Rosario Sarabia
The Barrow Ruptured Aneurysm Trial
Kyle M. Fargen and Brian L. Hoh
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.
Richard Kerr and Andrew Molyneux
Hasan A. Zaidi, M. Yashar S. Kalani, Robert F. Spetzler, Cameron G. McDougall and Felipe C. Albuquerque
Pediatric cerebral arteriovenous fistulas (AVFs) are rare but potentially lethal vascular lesions. Management strategies for these lesions have undergone considerable evolution in the last decade with the advent of new endovascular, surgical, and radiosurgical technologies. This study sought to review current treatment strategies and long-term clinical outcomes at a high-volume cerebrovascular institute.
A retrospective chart review was performed on patients with a diagnosis of cerebral AVF from 1999 to 2012. Patients with carotid-cavernous fistulas, vein of Galen malformations, and age > 18 years were excluded from final analysis. Medical history, surgical and nonsurgical treatment, and clinical outcomes were documented. Pre- and postoperative angiograms were analyzed to assess for obliteration of the fistula.
Seventeen patients with pial AVFs (29.4%), dural AVFs (64.7%), or mixed pial/dural AVFs (5.9%) were identified. The majority of lesions were paramedian (70.6%) and supratentorial (76.5%). The study population had a mean age of 6.4 years, with a slight male predominance (52.9%), and the most common presenting symptoms were seizures (23.5%), headaches (17.6%), congestive heart failure (11.7%), and enlarging head circumference (11.7%). Among patients who underwent intervention (n = 16), 56.3% were treated with endovascular therapy alone, 6.3% were treated with open surgery alone, and 37.5% required a multimodal approach. Overall, 93.8% of the treated patients received endovascular treatment, 43.8% received open surgery, and 12.5% received radiosurgery. Endovascular embolysates included Onyx (n = 5), N-butyl cyanoacrylate (NBCA; n = 4), or coil embolization (n = 7) with or without balloon assistance (n = 2). Complete angiographic obliteration was achieved in 87.5% at the last follow-up evaluation (mean follow-up 3.1 years). One infant with incomplete AVF obliteration died of congestive heart failure, and 1 patient with complete obliteration died of acute sinus thrombosis, with an overall complication rate of 18.8%.
Pediatric cerebral AVFs are challenging neurosurgical lesions. Although advancements in endovascular therapy in the last decade have greatly changed the natural course of this disease, a multidisciplinary approach remains necessary for a large subset of patients. Surgeon experience with a thorough analysis of preoperative imaging is paramount to achieving acceptable clinical outcomes.
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.