Gamma knife treatment of subfoveal, classic neovascularization in age-related macular degeneration: a pilot study.
OBJECTIVE
Age-related macular degeneration (AMD) is the leading cause of severe vision loss in people older than age 65 years in the western world. The visual acuity loss usually results from the ingrowth of new vessels from the choroid capillaries, so called choroidal neovascularization (CNV). The aim of this pilot study was to investigate the effect of a single-fraction gamma knife radiosurgery (GKS) on visual acuity and the growth pattern of CNV in patients with AMD.


METHODS
Ten patients with a mean age of 75 years and with a subfoveal, classic CNV due to AMD were enrolled in this study. All patients were treated with GKS in one fraction with a prescription dose of 10 Gy. The treatment target was the CNV located in the macula. Computerized tomography scans of the globe were obtained. After a follow up of 1 year visual acuity was stable in six patients and decreased in four. The size of the CNV could be stabilized in four patients, and in six an enlargement of these neovascular complexes was shown. No side effects, such as cataract formation, development of radiation-induced retinopathy, or optic neuropathy, have been observed so far.


CONCLUSIONS
Gamma knife radiosurgery seemed to have a beneficial effect on visual acuity in patients with AMD, but it failed to control growth of CNV in six patients. A longer follow up, a larger study population, and a randomized and controlled study are necessary for a final conclusion.
Haas
A
A
Department of Ophthalmology, Karl-Franzens-University, Graz, Austria. anton.haas@kfunigraz.ac.at
Papaefthymiou
G
G
Langmann
G
G
Schröttner
O
O
Feigl
B
B
Leber
K A
KA
Hanselmayer
R
R
Pendl
G
G
D000368:Aged; D020256:Choroidal Neovascularization / Q000175:diagnosis / Q000601:surgery*; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011183:Postoperative Complications / Q000209:etiology; D011446:Prospective Studies; D016634:Radiosurgery; D016896:Treatment Outcome; D014792:Visual Acuity