Abstract
Purpose::
To report on the visual outcome of verteporfin photodynamic therapy (PDT) in the treatment of subfoveal choroidal neovascularization (CNV) in patients with age-related macular degeneration (AMD) in routine clinical practice.
Methods::
All patients who commenced PDT in a single treatment center were studied prospectively in an observational cohort design. Standard refraction protocol was used to measure the visual acuity (VA) at baseline and 3 monthly and to measure the contrast sensitivity at baseline and 6 monthly. Values were recorded as number of letters read at 1 meter on standard charts. Lesions were characterized by stereoscopic fluorescein angiography. Patients eligible for treatment had CNV within 200 µm of the foveal centre and VA of ≥30 letters. When both eyes were treated the study eye was the first of the two requiring treatment.
Results::
1003 patients with CNV secondary to AMD commenced PDT between October 1999 and November 2006 (mean age 77.1 yrs, standard deviation (SD) 7.8). Lesion types included classic no occult: 719 (72%), predominantly classic with occult: 221 (22%), minimally classic with occult: 4 (0.4%), occult/ no classic: 5 (0.5%), retinal angiomatous proliferation: 35 (4%), idiopathic polypoidal choroidal neovascularisation: 6 (0.6%). Numbers of patients completing follow-up who started therapy prior to specific time points were: ≥12 months - 645 of 876 (74 %); ≥24 months 391 of 708 (55%). 122 patients completed ≥36 months of follow-up. Mean values of VA and CS (SD) were: baseline VA 48.5 (11.2), CS 21.4 (6.8); 3 months VA 43.1 (16.1), CS 21.3 (7.7); 6 months VA 40.1 (16.9), CS 20.8 (8.0); 12 months VA 38.6 (18.0), CS 21.7 (8.0); 24 months VA 39.0 (18.0), CS 22.3 (8.2); 36 months VA 40.0 (17.6), CS 24.1 (6.7). Changes in VA were: stable or improved - 12 months 36.3%, 24 months 40.3%; <15 letters lost - 12 months 25.6%, 24 months 23.8%; ≥15 letters - 12 months 38.0%, 24 months 36.8%. Numbers of letters lost at 12 months was positively correlated to baseline VA (p<0.0001) and lesion size (p<0.001) and negatively to baseline CS (p<0.001).
Conclusions::
Results of PDT are similar in established clinical practice to those seen in clinical trials and visual stabilization was prolonged. Greater amounts of vision are lost with better VA, larger lesion size and worse CS at baseline.
Keywords: age-related macular degeneration • photodynamic therapy • visual acuity