Abstract
Abstract: :
Purpose: To characterize the pattern changes on optical coherence tomography (OCT) after photodynamic therapy (PDT) with verteporfin for choroidal neovascularization (CNV). Methods: Twenty-six consecutive eyes that underwent PDT for subfoveal CNV were scanned with OCT pretreatment, one week posttreatment, and three months posttreatment. Horizontal OCT scans were analyzed to determine the central retinal thickness (CRT), central retinal pigment epithelium (RPE)/CNV complex thickness (CRPET), amount of subretinal fluid (SRF), and presence/absence of cystoid macular edema (CME). The measurements were performed in a masked fashion by two independent, experienced investigators. Results: The intra-class correlations for each of the variables were greater than 0.8, indicating excellent reproducibility and agreement between the observers. One week following PDT, 12/26 eyes (46%) showed a decrease in the CRT, 8/26 eyes (31%) showed no change (plus/minus 18.5 um), and 6/26 (23%) eyes showed an increase. Three months following PDT, 16/26 eyes (62%) demonstrated a decrease in CRT, 5/26 eyes (19%) showed no change, and 5/26 eyes (19%) showed an increase. Mean CRT decreased from 194 um to 155 um at one week (p=0.02), and to 151 um at three months (p=0.06). The CRPET was generally unchanged at one week and increased at 3 months following PDT. At one week, 11/26 eyes (42%) showed a decrease in CRPET, 6/26 eyes (23%) showed no change, and 9/26 eyes (35%) showed an increase. At three months, 3/26 eyes (12%) showed a decrease in CRPET, 6/26 eyes (23%) showed no change, and 17/26 eyes (65%) showed an increase. Mean CRPET was 119 um pre-PDT, 120 um one month post-PDT (p=0.94), and 168 um three months post-PDT (p=0.0001). SRF decreased in 57% at one week and 43% at three months. Nine of 26 eyes (35%) demonstrated CME pretreatment. Five of 9 (56%) had resolution of CME by one week and 6/9 (67%) had resolution by three months. Four of 17 eyes without pre-PDT CME developed CME at three months. Conclusion: As measured by OCT, PDT appears to decrease the CRT at one week and this persists at three months. The amount of CRT reduction may correspond to the reduction in SRF in most patients. This reduction appears to occur early as demonstrated at one week. In contrast, the CRPET does not change significantly at one week; however, the CRPET appears to increase significantly (29%) at three months. This may correspond to the increased subretinal fibrosis (of the RPE/CNV complex) that can be seen biomicroscopically following PDT. There appears to be a temporal pattern of OCT changes following PDT.
Keywords: 308 age-related macular degeneration • 432 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 516 photodynamic therapy