You could be reading the full-text of this article now if you...

If you have access to this article through your institution,
you can view this article in

Spinal Glomus (Type II) Arteriovenous Malformations: A Pooled Analysis of Hemorrhage Risk and Results of Intervention

Gross, Bradley A. MD; Du, Rose MD, PhD

Neurosurgery:
doi: 10.1227/NEU.0b013e318276b5d3
Research-Human-Clinical Studies
Abstract

BACKGROUND: The natural history and treatment results for spinal glomus (type II) arteriovenous malformations (AVMs) remain relatively obscure.

OBJECTIVE: To calculate spinal glomus (type II) AVM hemorrhages rates and amalgamate results of intervention.

METHODS: We performed a pooled analysis via the PubMed database through May 2012, including studies with at least 3 cases. Data on individual patients were extracted and analyzed using a Cox proportional hazards regression model to obtain hazard ratios for hemorrhage risk factors.

RESULTS: The annual hemorrhage rate before treatment was 4% (95% confidence interval [confidence interval]: 3%-6%), increasing to 10% (95% CI: 7%-16%) for AVMs with previous hemorrhage. The hazard ratio for hemorrhage after hemorrhagic presentation was 2.25 (95% CI: 0.71-7.07), increasing to 13.0 within the first 10 years (95% CI: 1.44-118). The overall rates of complete obliteration were 78% (95% CI: 72%-83%) for surgery and 33% (95% CI: 24%-43%) for endovascular treatment. Long-term clinical worsening occurred in 12% of patients after surgical treatment (95% CI: 8%-16%) and in 13% after endovascular treatment (95% CI: 7%-21%). No hemorrhages occurred after complete obliteration. After partial surgical treatment, the annual hemorrhage rate was 3% (95% CI: 1%-6%); no hemorrhages were reported over 196 patient-years after partial endovascular treatment.

CONCLUSION: Spinal glomus (type II) AVMs with previous hemorrhage, particularly within 10 years, demonstrated a greater risk of hemorrhage. Complete obliteration and even partial endovascular treatment significantly decreased their hemorrhage rate.

ABBREVIATIONS: AVM, arteriovenous malformation

CI, confidence interval

NBCA, N-butyl cyanoacrylate

PVA, polyvinyl alcohol

Author Information

Department of Neurological Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts

Correspondence: Rose Du, MD, PhD, Department of Neurological Surgery, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115. E-mail: rdu@partners.org

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.neurosurgery-online.com).

Received July 12, 2012

Accepted September 14, 2012

Copyright © by the Congress of Neurological Surgeons