Outcome after hemorrhage following Gamma Knife surgery for cerebral arteriovenous malformations

J Neurosurg. 2009 May;110(5):1003-9. doi: 10.3171/2008.10.17675.


Object: Although the effects of Gamma Knife surgery (GKS) on the risk of hemorrhage are poorly understood, a certain subset of patients does suffer bleeding after GKS. This study was undertaken to analyze the outcome of patients sustaining hemorrhage after GKS; it is the most feared complication of radiosurgical management of cerebral arteriovenous malformations (AVMs).

Methods: Between May 1997 and June 2006, 494 cerebral AVMs in 489 patients were treated using a Leksell Gamma Knife Model B, and follow-up evaluations were conducted until June 2007 at the All India Institute of Medical Sciences in New Delhi. Fourteen patients who sustained a hemorrhage after GKS formed the study group. In most of these patients conservative management was chosen.

Results: The mortality rate was 0% and there was a 7% risk of sustaining a severe deficit following rebleeding after GKS. None of the patients sustained rebleeding after complete obliteration. Patients with Spetzler-Martin Grade III or less had increased chances of hemorrhage after GKS (p < 0.002). The presence of deep venous drainage, aneurysm, venous hypertension, or periventricular location on angiography was common in patients with hemorrhage after GKS.

Conclusions: The risk of hemorrhage that remains following GKS for cerebral AVMs is highest in the 1st year after treatment. The present study showed a relatively good outcome even in cases with hemorrhage following GKS, with no deaths and minimal morbidity, further substantiating the safety and efficacy of the procedure.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Cerebral Hemorrhage / etiology*
  • Cerebral Hemorrhage / mortality
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Intracranial Arteriovenous Malformations / surgery*
  • Male
  • Middle Aged
  • Postoperative Complications
  • Radiosurgery*