Clinicopathological correlation of choroidal neovascularization after external beam radiotherapy in age-related macular degeneration.
OBJECTIVE
To analyze the histopathology of choroidal neovascularization after external beam radiotherapy in age-related macular degeneration.


METHODS
A retrospective non-case-matched comparative histopathologic study. The histoarchitecture of nine surgically removed subretinal specimens from nine patients that had undergone external beam radiotherapy for exudative age-related macular degeneration was studied. Seven patients had received 20 Gy in 10 fractions and two 15 Gy in 5 fractions with an average time interval between radiotherapy and surgical extraction of 14 months (range 3-28). A consecutive series of classic, mixed and occult choroidal neovascular membranes served as controls.


RESULTS
Clinical findings. Radiation-associated choroidal neovasculopathy was angiographically suspected in four patients: a coarse net of vessels on fluorescein angiography developing at the border of previously irradiated choroidal neovascularization was observed in three patients; blebs at the margin of a plaque on indocyanine green angiography were observed in two patients. Pathological findings. Diffuse drusen as well as intra-Bruch's fibrovascular tissue was found in all irradiated specimens. In four specimens an edematous vascularized layer was seen between diffuse drusen and normal-appearing intra-Bruch's fibrovascular tissue. This lesion was not found in the control specimens. A particular correlation for the bleb lesion was not recognized.


CONCLUSIONS
The appearance of an edematous subretinal pigment epithelial vascularized layer between diffuse drusen and normal-appearing fibrovascular tissue in four of nine irradiated membranes may be secondary to previous irradiation. It may correlate with the unusual exudative manifestations observed after external beam radiotherapy.
Aisenbrey
S
S
Department of Vitreo-Retinal Surgery, Center of Ophthalmology, University of Cologne, Cologne, Germany.
Lafaut
B A
BA
Reynders
S
S
Szurman
P
P
Grisanti
S
S
Vanden Broecke
C
C
Walter
P
P
Bartz-Schmidt
K U
KU
D000368:Aged; D000369:Aged, 80 and over; D016570:Bruch Membrane / Q000473:pathology; D002829:Choroid / Q000098:blood supply / Q000528:radiation effects*; D020256:Choroidal Neovascularization / Q000175:diagnosis / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D008268:Macular Degeneration / Q000150:complications / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D010857:Pigment Epithelium of Eye / Q000473:pathology; D011832:Radiation Injuries / Q000175:diagnosis / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D011878:Radiotherapy / Q000009:adverse effects*; D012189:Retrospective Studies