title: Intracranial vascular malformations: imaging of charged-particle radiosurgery. Part II. Complications.
abstract: Seven of 24 patients with intracranial vascular malformations who were treated with helium-ion Bragg-peak radiosurgery had complications of therapy. New symptoms and corresponding radiologic abnormalities developed 4-28 months after therapy. Five patients had similar patterns of white matter changes and mass effect on computed tomographic scans and magnetic resonance images. The abnormalities were centered in the radiation field. Gray matter changes and abnormal enhancement in the thalamus and hypothalamus outside the radiation field developed in one patient. This patient also had vasculopathic changes on angiograms. Rapidly progressive large vessel vasculopathy developed in another patient and caused occlusion of major vessels. Thus, different mechanisms may be involved in the complications of heavy-ion radiosurgery.
authors.affiliation: Department of Diagnostic Radiology and Nuclear Medicine, Stanford University School of Medicine, CA 94305.
authors.forename: M P
authors.initials: MP
authors.lastname: Marks
authors.forename: R L
authors.initials: RL
authors.lastname: Delapaz
authors.forename: J I
authors.initials: JI
authors.lastname: Fabrikant
authors.forename: K A
authors.initials: KA
authors.lastname: Frankel
authors.forename: M H
authors.initials: MH
authors.lastname: Phillips
authors.forename: R P
authors.initials: RP
authors.lastname: Levy
authors.forename: D R
authors.initials: DR
authors.lastname: Enzmann
mesh_terms: D000328:Adult; D001921:Brain / Q000528:radiation effects; D002533:Cerebral Angiography; D005260:Female; D006371:Helium / Q000627:therapeutic use; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000532:radiotherapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D010315:Particle Accelerators; D011832:Radiation Injuries / Q000175:diagnosis* / Q000209:etiology; D011878:Radiotherapy / Q000009:adverse effects* / Q000379:methods; D013238:Stereotaxic Techniques; D013997:Time Factors; D014057:Tomography, X-Ray Computed
chemical_list: D006371:Helium