Focal macular electroretinograms before and after removal of choroidal neovascular lesions.
OBJECTIVE
To evaluate the changes in focal macular electroretinograms (fmERGs) after surgical removal of choroidal neovascular (CNV) lesions.


METHODS
Fourteen patients (14 eyes) with subfoveal or juxtafoveal CNV associated with age-related macular degeneration and 1 patient with idiopathic CNV underwent vitrectomy and removal of the lesions. fmERGs elicited by a 15 degree stimulus were recorded before and 3 months after surgery. Optical coherence tomography (OCT) was performed to measure the foveal and parafoveal thickness before and 3 months after surgery.


RESULTS
Preoperative fmERGs were markedly reduced in all eyes. The mean amplitude of the b-wave in 15 eyes recorded 3 months after surgery increased significantly (P = 0.0022, Wilcoxon signed rank test). In all eyes except two with nearly nonrecordable a- and b- waves, the mean b-wave-to-a-wave ratio after surgery increased significantly in all eyes (P = 0.0330, Wilcoxon signed rank test). The percentage increase in the b-wave amplitude correlated significantly with the percentage decrease in the mean parafoveal retinal thickness (r = 0.688, P = 0.0076).


CONCLUSIONS
The decreased macular ERGs were partially recoverable in the early postoperative period. The decreased retinal edema after surgery may have contributed to this recovery.
Terasaki
Hiroko
H
Department of Ophthalmology, Nagoya University School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya 466, Japan. terasaki@med.nagoya-u.ac.jp
Miyake
Yozo
Y
Niwa
Takashi
T
Ito
Yasuki
Y
Suzuki
Toshimitsu
T
Kikuchi
Masato
M
Kondo
Mineo
M
D000328:Adult; D000368:Aged; D020256:Choroidal Neovascularization / Q000209:etiology / Q000503:physiopathology* / Q000601:surgery*; D004596:Electroretinography; D006801:Humans; D007368:Interferometry; D008027:Light; D008266:Macula Lutea / Q000502:physiology*; D008268:Macular Degeneration / Q000150:complications; D008875:Middle Aged; D014054:Tomography; D014792:Visual Acuity; D014821:Vitrectomy