Adjusting for age at time of surgery , gender , interval between preoperative and postoperative visits , and type and severity of cataract , the mean changes in visual acuity were as follows : eyes with mild AMD ( n = 30 ) gained 11.2 letters ( 95 % confidence interval [ CI ] , 6.9-15 .5 ) , eyes with moderate AMD ( n = 346 ) gained 11.1 letters ( 95 % CI , 9.1-13 .2 ) , eyes with severe AMD ( n = 462 ) gained 8.7 letters ( 95 % CI , 6.7-10 .7 ) , eyes with noncentral geographic atrophy ( n = 70 ) gained 8.9 letters ( 95 % CI , 5.8-12 .1 ) , and eyes with advanced AMD ( central geographic atrophy , neovascular disease , or both ; n = 324 ) gained 6.8 letters ( 95 % CI , 4.9-8 .8 ) .