title: Draining vein shielding in intracranial arteriovenous malformations during gamma-knife: a new way of preventing post gamma-knife edema and hemorrhage.
abstract: BACKGROUND
  Following gamma knife (GK) therapy for intracranial arteriovenous malformations (AVMs), obliteration of the nidus occurs over several years. During this period, complications like rebleeding have been attributed to early draining vein occlusion.
  
  
  OBJECTIVE
  To evaluate if shielding the draining vein(s) during GK therapy prevents early draining vein obliteration and complications following GK therapy.
  
  
  METHODS
  This was a nonrandomized case-control study over 5 years (January 2009-February 2014) and included patients with intracranial AVM who underwent GK therapy at our center. All patients who underwent draining vein shielding by the senior author (D.A.) were included in the test group, and patients who did not undergo draining vein shielding were put in the control group. Patients were followed up for at least 6 months (and every 6 months thereafter) clinically as well as radiologically with computed tomography head scans/magnetic resonance imaging brain scans to check for postradiosurgery imaging (PRI) changes.
  
  
  RESULTS
  One hundred eighty-five patients were included in this study, of which 96 were in the control group and 89 were in the test group. Both groups were well matched in demographics, comorbidities, adjuvant treatment, angioarchitecture, and radiation dosing. Because of shielding, the test group patients received significantly less radiation to the draining vein than the control group (P = .001). On follow-up, a significantly lower number of patients in the test group had new neurological deficits (P = .001), intracranial hemorrhage (P = .03), and PRI changes (P = .002).
  
  
  CONCLUSIONS
  Shielding of the draining vein is a potent new strategy in minimizing PRI and hemorrhage as well as clinical deterioration following GK therapy for intracranial AVMs.
authors: Department of Neurosurgery and Gamma Knife, All India Institute of Medical Sciences, New Delhi, India.
authors: Ratnadip
authors: R
authors: Bose
authors: Deepak
authors: D
authors: Agrawal
authors: Manmohanjit
authors: M
authors: Singh
authors: Shashank S
authors: SS
authors: Kale
authors: Natanasabapathi
authors: N
authors: Gopishankar
authors: Raj K
authors: RK
authors: Bisht
authors: Bhawani S
authors: BS
authors: Sharma
mesh_terms: D000328:Adult; D001929:Brain Edema / Q000209:etiology / Q000517:prevention & control; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D020300:Intracranial Hemorrhages / Q000209:etiology / Q000517:prevention & control; D008279:Magnetic Resonance Imaging / Q000295:instrumentation; D008297:Male; D008875:Middle Aged; D011835:Radiation Protection / Q000379:methods*; D016634:Radiosurgery / Q000009:adverse effects* / Q000379:methods*; D016896:Treatment Outcome; D014680:Veins / Q000528:radiation effects* / Q000601:surgery