Abstract
Purpose:
To assess the effect of cataract surgery on IOP and glaucoma medication usage in eyes previously implanted with aqueous shunts.
Methods:
Consecutive interventional case series of eyes that underwent aqueous shunt implantation followed by phacoemulsification between 1998 and 2010. Eligible eyes were identified from a prospectively acquired database of aqueous shunt implants. Patients over the age of 16 with a minimum of 1-year follow-up after phacoemulsification were included. Patients with less than 3 months between shunt surgery and phacoemulsification, with phacoemulsification performed in combination with other ocular procedures involving the aqueous shunt, or with non-IOP related surgery within 1 year of phacoemulsification were excluded. Records of eligible patients were reviewed and the following collected: visual acuity, IOP, glaucoma medication usage and further glaucoma surgical procedures. Data was collected before phacoemulsification and postoperatively at 1 day; 1 week; 1, 3, 6, 12, 24 months; and at last follow-up. Comparisons were made using a two-tailed Student t test where a P value below 0.05 was used to determine statistical significance.
Results:
A total of 531 eyes underwent aqueous shunt implant during the study. Of these, 47 (8.85%) eyes subsequently underwent phacoemulsification and met the criteria. The mean age at shunt implantation was 53.0 years ± 13.7 (range 17-72 years). Phacoemulsification was performed 15.3 months ± 11.2 (mean ± SD)(range 4-60 months) after aqueous shunt insertion and followed-up for an average of 49.2 months ± 33.6 (mean ± SD)(range 12-150 months). Visual acuity improved from 1.13 logMAR ± 0.79 (mean ± SD) and was an average of 0.72 logMAR ± 0.79 (mean ± SD) at last follow-up. There was significant improvement to visual acuity at all times after phacoemulsification (P<0.05). IOP at last follow-up was 13.89mmHg ± 4.24 (mean ± SD) compared to 14.77mmHg ± 5.24 (mean ± SD) before phacoemulsification. IOP was significantly lower than before phacoemulsification at only the one week time-point (P=0.013). The mean number of glaucoma medications has not increased: 1 (0.85) ± 1.02 before phacoemulsification and 1 (1.04) ± 1.18 (mean ± SD) at last follow-up (P = 0.38).
Conclusions:
Phacoemulsification in eyes previously implanted with aqueous shunts for glaucoma improves visual acuity without significantly altering the IOP or the number of medication used.
Keywords: 743 treatment outcomes of cataract surgery