title: Fractionated, stereotactic proton beam treatment of cerebral arteriovenous malformations.
abstract: OBJECTIVE
  To evaluate the therapeutic efficiency and adverse effects of stereotactic proton beam treatment of cerebral arteriovenous malformations (AVM).
  
  
  METHODS
  Twenty-six patients treated in Uppsala during 1991-97 were included (men = 14, women = 12; mean age = 39, range = 23-64). The nidus volumes ranged from 0.3 to 102 ml (mean = 24, median = 13). The follow-up included clinical evaluation, magnetic resonance imaging (and/or computed tomography) every 6-12 months for 3 years and final angiography.
  
  
  RESULTS
  The volume changes at final follow-up in AVMs >25 ml were -89, -85, -44, -29, -7, 0, 0, +5 and +18 (%); in AVMs 11-24 ml, -100, -100, -97, -92 and 0 (%); and in AVMs <10 ml, -100, -100, -100, -100, -100, -99, -98, -50, -0 and +40 (%). Two patients were lost to follow-up due to cerebral haemorrhage and myocardial infarction. Radiology displayed significant perifocal oedema in one patient and slight oedema in four patients. Of nine patients with epilepsy, seven became seizure-free after therapy while two continued to suffer from seizures.
  
  
  CONCLUSIONS
  Proton beam irradiation is successful in a relatively high proportion of intermediate and large-sized cerebral AVMs. The adverse effects are acceptable. The advantage of proton treatment compared with gamma knife and LINAC stereotactic irradiation is that protons can irradiate even large volumes with a very sharp dose profile against normal surroundings. Thus, proton beam irradiation is a valuable option in the treatment of AVMs larger than 10 ml.
authors.affiliation: Department of Neurosurgery, University Hospital, Uppsala, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Silander
authors.forename: L
authors.initials: L
authors.lastname: Pellettieri
authors.forename: P
authors.initials: P
authors.lastname: Enblad
authors.forename: A
authors.initials: A
authors.lastname: Montelius
authors.forename: E
authors.initials: E
authors.lastname: Grusell
authors.forename: C
authors.initials: C
authors.lastname: Vallhagen-Dahlgren
authors.forename: U
authors.initials: U
authors.lastname: Isacsson
authors.forename: G
authors.initials: G
authors.lastname: Nyberg
authors.forename: U
authors.initials: U
authors.lastname: Moström
authors.forename: A
authors.initials: A
authors.lastname: Lilja
authors.forename: G
authors.initials: G
authors.lastname: Gál
authors.forename: E
authors.initials: E
authors.lastname: Blomquist
mesh_terms: D000328:Adult; D002543:Cerebral Hemorrhage / Q000209:etiology; D019583:Dose Fractionation, Radiation; D004487:Edema / Q000209:etiology; D004827:Epilepsy / Q000209:etiology; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D061766:Proton Therapy; D013238:Stereotaxic Techniques; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D011522:Protons
chemical_list: D011522:Protons