Purchase this article with an account.
K. Ishikawa, H. Terasaki, C. Kobayashi, Y. Niwa, C. Piao, Y. Ito, M. Kondo, Y. Miyake; Focal Macular Electroretinograms and OCT before and after Transpupillary Thermotherapy . Invest. Ophthalmol. Vis. Sci. 2003;44(13):1784.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To evaluate the changes in focal macular electroretinograms (FMERGs) and foveal thickness after transpupillary thermotherapy (TTT) for choroidal neovascularization (CNV). Methods: Twenty-six eyes (7 with predominantly classic CNV, 16 with predominantly occult CNV, and 3 with polypoidal choroidal vasculopathy) were treated by TTT. TTT was delivered by an infrared diode laser of 810 nm wavelength with the following parameters; power from 80 to 330 mW, duration of 60 seconds, and spot size of 1.2, 2.0 and 3.0 mm depending on the area of the CNV. FMERGs elicited by a 15°stimulus were recorded, and optical coherence tomography (OCT) was performed to measure the foveal thickness before, and 3 and 6 months after TTT. Results: The best corrected visual acuity 6 months after TTT improved by at least two lines of the standard Japanese acuity chart in 5 eyes, was maintained in 19 eyes, and decreased in 2 eyes. FMERGs before TTT were markedly reduced in all eyes. The mean foveal thickness before TTT was increased. The mean amplitude and implict time of the a- and b-waves in all treated eyes were unchanged after TTT. The mean foveal retinal thickness decreased significantly after TTT in all eyes (P=0.0149, Wilcoxon signed rank test). When analyzed by the type of CNV, the mean amplitude of the b-wave in occult CNV was increased significantly (p=0.0082), and the foveal thickness tended to decrease (p=0.0685) 6 months after TTT (Wilcoxon signed rank test). Conclusions: Although the foveal thickness decreased, the macular function did not change significantly at least 6 months after TTT. This suggested that TTT may not have damaged macular function very much. The decreased amplitude of the b-wave was partially recoverable in occult type of CNV after TTT possibly due to the decreased retinal thickness.
This PDF is available to Subscribers Only