Abstract
Abstract: :
Purpose: To determine the long term efficacy of transpupillary thermotherapy (TTT) for the treatment of occult choroidal neovascular membranes (CNV) secondary to age-related macular degeneration (AMD). Methods: A retrospective, non-randomized study of 65 consecutive eyes of 64 patients was performed. All eyes had AMD with subfoveal occult CNV, defined as less than 50% classic component on fluorescein angiography. All eyes were evaluated pre-treatment and at 3 month intervals post-treatment. Evaluation at each visit consisted of Snellen visual acuity and biomicroscopic assessment of subretinal exudation. Retinal photography and fluorescein angiography was performed pre-treatment, at 3,6,12, and 24 months post-treatment, and when re-treatment was being considered . Pre-treatment visual acuity ranged from 20/60 to 20/800. Follow-up ranged from 27 months to 33 months. TTT was applied using an 810 nm diode laser. Laser spot size diameter on the retina ranged from 1.2 mm to 6.0 mm. A baseline power setting of 247 mW/ mm spot size diameter was used for the majority of eyes, but was varied for some eyes due to racial pigmentation, degree of exudation, and presence of fibrosis. Treatment was given for 60 seconds. No visible colour change of the retina was observed during treatment. Eyes were re-treated after at least three months if there was a decrease in visual acuity with no decrease in subretinal exudation and the presence of subfoveal fluorescein leakage. Results: Forty-eight of 65 (74%) eyes had stable visual acuity ( no change, or within one line of pre-treatment visual acuity). Seven of 65 (11%) eyes had an improvement in vision of 2 or more lines. Ten of 65 (15%) eyes had a loss of 2 or more lines of vision. Fifty-nine of 65 (91%) eyes had a decrease in clinical subretinal exudation. Sixty-two of 65 (95%) eyes had a decrease in subfoveal leakage on fluorescein angiography, and 52 of 65 (80%) eyes had complete absence of leakage on fluorescein angiography. Fifty of 65 (77%) eyes required only a single treatment, 10 of 65 (15%) eyes required two treatments, and 5 of 65 (8%) eyes required three treatments. Conclusions: TTT is effective at preserving vision and reducing subretinal exudation and CNV leakage in patients followed for 27 to 33 months after treatment.
Keywords: age-related macular degeneration • choroid: neovascularization • laser