Simulated treatment of recurrent choroidal neovascularization in primate retina. Comparative histopathologic findings
W. E. Smiddy, S. L. Fine, H. A. Quigley, R. M. Hohman and G. Dunkelberger
We simulated the treatment of recurrent choroidal neovascular membranes
(CNVM) by applying two courses of laser treatment to monkey retinas. Argon
green, argon blue-green, and krypton red lasers (KRLs) were used in
juxtafoveal, papillomacular bundle, and nonmacular areas. The effects were
examined clinically and histopathologically. Results of once-treated
control eyes were consistent with those of previous studies. Repeat
treatment, however, resulted in full-thickness retinal destruction or
necrosis with all laser modalities and in all fundus locations. These
results are consistent with the absorptive characteristics of xanthophyll
and melanin and suggest only limited advantages to the KRL when treatment
of recurrent CNVM is performed in a previously treated area of the fundus.
However, treatment of recurrent CNVM is still probably most successful with
a KRL, because recurrent CNVM is usually at a border of a photocoagulation
scar, where the retina is still untreated, and because histologic studies
have demonstrated inner retinal sparing with a KRL in juxtafoveal areas.
