Purpose: After initial encouraging results with the accommodative 1CU posterio r chamber lens (PCIOL), we investigated the rate, the postoperative time point o f posterior capsular opacification (PCO) necessitating YAG capsulotomy and the a ccommodative range after Nd: YAG capsulotomy in patients with 1CU-PCIOL. Patien ts and methods: This prosective clinical study included 65 patients who underwen t phacoemulsification and implantation of the accommodative 1CU-PCIOL with post operative follow-up from 3 to 24 months. Postoperative examination was performe d 3, 6 and 12 months after surgery, then before and 6 weeks after Nd: YAG capsul otomy. Measurements included: the best corrected distance visual acuity, distanc e refraction, near visual acuity (Birkhauser charts in 35 cm) obtained with be st distance correction, accommodative range measured by subjective near point wi th an accodommometer and defocusing with a visual acuity fall to 0.4. Results: B oth best corrected distance visual acuity (1.1±0.1) and near visual acuity with best distance correction (0.4±0.1) remained stable over the follow-up period until 12 months postoperatively. The accommodative range determined by near poin t was stable (mean 2.0±0.5 D). Also, the defocusing range remained stable over 12 months (1.8±0.4 D). A clinically relevant posterior c apsule opacification with a significant decrease of visual acuity (0.4±0.2) and a need for Nd: YAG capsulotomy was diagnosed in 12 patients between 15 and 22 ( mean 20±4, median 20) months postoperatively. All capsulotomies were performed without complication. Six weeks after capsulotomy, best corrected distance visua l acuity was improved (1.1±0.1), near visual acuity with best distance correcti on was 0.4±0.1 and the accommodative range determined by near point was 1.95±0 .6 D and by defocusing was 1.88±0.47 D. Six weeks after capsulotomy, measuremen ts of the accommodative range did not show any statistical difference to the 12 -month results before the occurrence of PCO (P >0.5). Conclusions: A clinically relevant PCO with a significant decrease of visual acuity necessitating Nd: YAG capsulotomy occurred mainly after 15 postoperative months in patients with 1CU. Our results indicate that Nd: YAG capsulotomy may not affect the accommodation ability of the 1CU. Nevertheless, long-term studies are needed to further analy ze the accommodative properties. Purpose: After initial encourage results with the accommodative 1CU posterio r chamber lens (PCIOL), we investigated the rate, the postoperative time point of posterior capsular opacification (PCO) necessitating YAG capsulotomy and the a ccommodative range after Nd: YAG capsulotomy in patients with 1CU-PCIOL. Patien ts and methods: This prosective clinical study included 65 patients who underwen t phacoemulsification and implantation of the accommodative 1CU-PCIOL with post operative follow-up from 3 to 24 months. Postoperative examination was performe d 3, 6 and 12 months after surgery, then before and 6 weeks after Nd: YAG capsulotomy. Measurements included: the best corrected distance visual acuity, distanc e refraction, near visual acuity (Birkhöauser charts in 35 cm) obtained with be st distance correction, accommodative range measured by subjective near point wi th an accodomometer and defocusing with a visual acuity fall to 0.4. Results: B oth best corrected distance visu The acuity (1.1 ± 0.1) and near visual acuity with best distance correction (0.4 ± 0.1) remained stable over the follow-up period until 12 months postoperatively. The accommodative range determined by near poin t was stable (mean 2.0 ± 0.5 D) Also, the defocusing range remained stable over 12 months (1.8 ± 0.4 D). A clinically relevant posterior c apsule opacification with a significant decrease of visual acuity (0.4 ± 0.2) and a need for Nd: YAG capsulotomy was diagnosed in 12 patients Six weeks after capsulotomy, best corrected distance visua l acuity was improved (1.1 ± 0.1), near visual acuity with best distance correcti on was 0.4 ± 0.1 and the accommodative range determined by near point was 1.95 ± 0.6D and by defocusing was 1.88 ± 0.47 D. Six weeks after capsulotomy, measuremen ts of the accommodative range did not show any statistical difference to the 12 -month re sults beforeThe results of PCO (P> 0.5). Conclusions: A clinically relevant PCO with a significant decrease of visual acuity necessitating Nd: YAG capsulotomy occurred mainly after 15 postoperative months in patients with 1CU. Our results indicate that Nd: YAG capsulotomy may not affect The accommodation ability of the 1CU. Nevertheless, long-term studies are needed to further analy ze the accommodative properties.