Purpose: A prospective longitudinal study was initiated to analyze the correlation between the prognosis for the second eyes of patients with unilateral late exudative AMD and the disease phenotype.
Methods: Of the187 patients with unilateral late exudative AMD recruited, 130 (69.5%) had predominantly classic CNV without pigment epithelium detachment (PED) (CNV group), and 57 (30.5%) had occult CNV with serous PED (PED group). Patients were reexamined by ophthalmoscopy and angiography every 6 months for up to 80 months. The end point was ETDRS visual acuity change of 3 lines or more due to late AMD in the second eye.
Results: During follow-up 53 (28.3%) patients reached the end point: 32 (24.6%) in the CNV group and 21 (36.8%) in the PED group. The major prognostic factor for the risk of visual loss in the second eye was the type of late AMD in the first eye (CNV group 6-7% per year, PED group 15-16% per year ( P<0.001). There was significant symmetry between the new exudative lesion in the second eye and that in the first, and significant differences in the density and fluorescence of drusen in the second eye between the two groups.
Conclusions: Patients with occult CNV with serous PED in the first eye have a significantly higher risk of visual loss in the second eye than patients with CNV without PED. This distinction may be important for future clinical studies. In addition, segregation of AMD by phenotype is necessary in the analysis of genes conferring risk of AMD.