Hypertension may not convey excess risk of radiation-induced change in Gamma Knife radiosurgery of cerebral arteriovenous malformationMark Quigg1, Chun-Po Yen1, Micaela Chatman2, Anders Quigg2, Jason P. Sheehan, PhD31Charlottesville, United States 2University of Virginia, Dept of Neurology 3Department of Neurosurgery, University of Virginia Keywords: arteriovenous malformation, Imaging, gamma knife, complications, arteriovenous fistula
No studies exist to determine the excess risk of radiation toxicity in patients with diabetes mellitus or hypertension who undergo Gamma Knife radiosurgery (RS) of cerebral arteriovenous malformation (AVM). Limited studies suggest DM and HTN are associated with excessive complications following fractionated radiotherapy of lesions outside the central nervous system.
Our purpose was to study risk factors for radiation toxicity.
This single-center, retrospective, consecutive case series determined the associations between radiation-induced changes (RIC) visible on MRI following RS for AVM. Patients with incomplete follow-up and children < 17 years were excluded. History or medication use for DM or HTN, tobacco use, age, sex, AVM volume, Spetzler-Martin severity grade (1-2 vs 3-5), pre-RS surgery, embolization, or hemorrhage were compared between RIC(+) and RIC(–) groups by univariate and logistic regression multivariate analyses.
RIC occurred in 38% of 539 adults within 12±10 months (mean±standard deviation) of RS in a median follow-up of 55 months. 34% of those with RIC had symptoms of headache, neurological deficits, or new-onset seizures, with larger RIC associated with greater symptomatology. DM (3% of sample) was significantly higher with RIC (RIC(+) 5%, RIC(–) 1%, P=0.02 Fisher’s exact test), but HTN (20%) was not. Larger AVM volume and Spetzler-Martin grades 3-5 had significant associations with RIC. The proportion of patients with pre-RS surgery and pre-RS hemorrhage were significantly decreased in the RIC(+) group. Older age had borderline associations with RIC. Sex, tobacco use, or pre-RS AVM embolization had no associations with RIC. The factors significantly associated with RIC in multivariate analysis were larger AVM volumes, Spetzler-Martin grades 3-5, and absence of pre-RS surgery.
This was a retrospective study.
HTN, traditionally considered to increase the risk of RS in the CNS, did not carry significant risks in development of RIC. The number of patients with DM was too low to determine risk accurately.
We did not find that hypertension nor diabetes increased radiation risks. Project Roles:
M. Quigg (), C. Yen (), M. Chatman (), A. Quigg (), J. Sheehan ()