Advances in medical therapy for glaucoma.

PURPOSE OF REVIEW: To discuss a new class of medication that has recently become available for the treatment of glaucoma; as well as share insights into developments in glaucoma medicine administration which has the potential to revolutionize medical therapy for glaucoma. RECENT FINDINGS: Newly available eye drops, netarsudil 0.02% and latanoprostene bunod 0.024%, are improving aqueous outflow through the conventional outflow tract. Other new developments in medical glaucoma are focused on alternative methods for sustained glaucoma medication delivery. SUMMARY: Newer medications may be able to extend the duration of medically controlled glaucoma, delaying or possibly eliminating the need of glaucoma surgery for some patients. Alternative methods of delivery for glaucoma medications may be a key factor in improving outcomes with currently available medications.

Incidence rate and occurrence of visually significant cataract formation and corneal decompensation after implantation of Verisyse/Artisan phakic intraocular lens.

PURPOSE: To evaluate the incidence rate and indications for explantation of Verisyse phakic intraocular lenses (pIOLs) over a 13.6 year period. SUBJECTS AND METHODS: Case series describing six cases of explantation of Verisyse pIOLs, out of 213 eyes with Verisyse pIOLs, implanted over a 13.6 year period by one surgeon at one institution, with mean follow-up of 5.6 years per eye. RESULTS: Four pIOLs were removed to facilitate extraction of a visually significant cataract, one was removed due to both cataract formation and development of corneal decompensation, and another was removed due to development of localized peripheral corneal decompensation. The incidence rate of pIOL removal was five per 1,000 patient-years with pIOL. Mean time from insertion of pIOL to cataract removal was 9.3 years (range 4.0-12.6 years). Mean time from insertion of pIOL to development of corneal decompensation was 10 years (range 6.9-13 years). There was no increase in the rate of cataract extraction in the pIOL population compared to the general population. CONCLUSION: Cataracts may develop in patients with pIOLs, necessitating removal of the pIOL. Corneal decompensation is a serious complication that appears to be directly related to pIOLs. Corneal decompensation can occur up to 13 years following implantation of pIOLs, and long-term follow-up is important to monitor for this complication.

Rate of ectasia and incidence of irregular topography in patients with unidentified preoperative risk factors undergoing femtosecond laser-assisted LASIK.

PURPOSE: To report the rate of postoperative ectasia after laser-assisted in situ keratomileusis (LASIK) with femtosecond laser-assisted flap creation, in a population of patients with no identified preoperative risk factors. METHODS: A retrospective case review of 1,992 eyes (1,364 patients) treated between March 2007 and January 2009 was conducted, with a follow up of over 4 years. After identifying cases of ectasia, all the patient charts were examined retrospectively for preoperative findings suggestive of forme fruste keratoconus (FFKC). RESULTS: Five eyes of four patients with post-LASIK ectasia were identified. All eyes passed preoperative screening and received bilateral LASIK. One of the five patients developed ectasia in both eyes. Three patients retrospectively revealed preoperative topography suggestive of FFKC, while one patient had no identifiable preoperative risk factors. Upon review of all the charts, a total 69 eyes, including four of the five eyes with ectasia, were retrospectively found to have topographies suggestive of FFKC. CONCLUSION: We identified four cases of post-LASIK ectasia that had risk factors for FFKC on reexamination of the chart and one case of post-LASIK ectasia with no identifiable preoperative risk factors. The most conservative screening recommendations would not have precluded this patient from LASIK. The rate of purely iatrogenic post-LASIK ectasia at our center was 0.05% (1/1,992), and the total rate of post-LASIK ectasia for our entire study was 0.25% (1/398). The rate of eyes with unrecognized preoperative FFKC that developed post-LASIK ectasia was 5.8% (1/17).

Antimicrobial effect of silver-impregnated cellulose: potential for antimicrobial therapy.

BACKGROUND: Silver has long been known to have antimicrobial activity. To incorporate this property into multiple applications, a silver-impregnated cellulose (SIC) with low cytotoxicity to human cells was developed. SIC differs from other silver treatment methods in that the leaching of silver particles is non-existent and the release of ionic silver is highly controlled. RESULTS: Candida albicans, Micrococcus luteu, Pseudomonas putida, and Escherichia coli were used for antimicrobial testing. No microbial cells were able to grow in the presence of SIC at concentrations above 0.0035 Ag w/v %. Even at a concentration of 0.00035 Ag w/v %, P. putida and M. luteu failed to grow, and C. albicans and E. coli exhibited diminished growth. To determine the cytotoxic effect of silver on human cells, five different concentrations of SIC were tested on human fibroblasts. In SIC concentrations of 0.035 Ag w/v % and below, no cytotoxicity was observed. CONCLUSION: The optimal concentration of SIC for a broad range of anti-microbial activity and low or negligible cytotoxicity was 0.0035 Ag w/v %. Although the highly controlled releasing characteristics of SIC would prove a substantial improvement over current technologies, further investigation for genotoxicity and other biocompatibility test will be required.