The impact of arteriovenous malformation radiosurgery on the brain: From morphology and perfusion to neurocognition.
The therapeutic aims of brain arteriovenous malformation (AVM) radiosurgery are multiple. Protecting patients from rebleeding is the prime goal. Among the others, hemodynamics, perfusion and neurocognition recovery are interesting and important. Anatomically AVM contains an abnormal cluster of vascular networks (nidus) between arteries and veins. Hemodynamically the nidus contains a low resistance and causes high-flow transnidal shunts between both sides of the nidus. The shunts cause hypotension in the neighboring arteries and diversion of blood from the adjacent brain tissues. The diversion disturbs brain hemodynamics. Radiosurgery, by eliminating the nidus, reconstitutes normal brain hemodynamics. From the early stage after radiosurgery, the abnormal transnidal flows gradually decrease, and the adjacent hemodynamics recovers toward normal. For nonhemorrhagic AVM, improvement of seizure control and stable or improved neurological status are observed clinically. The radiosurgical effects are also reflected in the recovery of metabolism in the adjacent brain and neurocognitive function paralleling the hemodynamic normalization. Morphological cure of AVM and the associated recovery of brain hemodynamics, metabolism and neurocognitive function form the therapeutic rationale of AVM radiosurgery.
Guo
W Y
WY
Department of Radiology, Taipei Veterans General Hospital and School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC. wyguo@vghtpe.gov.tw
Lee
S M
SM
Chang
Y C
YC
Pan
H C
HC
D000293:Adolescent; D000328:Adult; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D003072:Cognition Disorders / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000503:physiopathology / Q000601:surgery*; D018810:Magnetic Resonance Angiography; D008297:Male; D011183:Postoperative Complications / Q000503:physiopathology / Q000517:prevention & control; D011446:Prospective Studies; D016634:Radiosurgery; D020127:Recovery of Function; D016896:Treatment Outcome