Evaluation of the ocular surface in asymptomatic glaucoma patients on topical medications and following trabeculectomy - A cross-sectional study

Purpose: This present prospective, cross-sectional study aims to comprehensively evaluate the ocular surface in asymptomatic patients with diffuse blebs after trabeculectomy versus chronic anti?glaucoma medication use and compare it with the age?matched normal population. Methods: Objective clinical evaluation was done by tear film break?up time (TBUT) and Schirmer’s test (ST) in the three groups– trabeculectomy >6 months with a diffuse bleb (Wurzburg bleb classification score ?10), chronic anti?glaucoma medication (AGM >6 months) group, and normal population. In all groups, tear film osmolarity was checked with the TearLab® device (TearLab Corp., CA, USA), and subjective evaluation was performed by administering Ocular Surface Disease Index (OSDI) questionnaire. Patients already on chronic lubricants or any other drug for the treatment of dry eyes (viz. steroids, cyclosporin) or having symptoms suggestive of an abnormal ocular surface, who had undergone refractive or intraocular surgery, and contact lens users were excluded. Results: In total, 104 subjects/eyes were recruited over 6 weeks. Thirty?six eyes recruited in the trab group were compared with 33 eyes studied in the AGM group, and both these groups were compared to 35 normal eyes. When compared to normals, TBUT and ST were significantly lower (P = 0.003 and 0.014) and osmolarity and OSDI were statistically significantly higher (P = 0.007 and 0.003) in the AGM group, whereas only TBUT was statistically significantly different (P = 0.009) when the trab group was compared to normals. Also, when the trab group was compared to the AGM group, ST was found to be higher (P = 0.003) and osmolarity was lower (P = 0.034). Conclusion: To conclude, ocular surface is affected even in asymptomatic patients on AGM but near normalcy is possible following trabeculectomy when blebs are diffuse.

The Importance of Evaluation of Corneal Endothelial Cell Count in Glaucoma Patients

PURPOSE: To evaluate the possible causes of decreased central corneal endothelial cell count in glaucoma patients and to acknowledge the importance of central corneal endothelial cell count evaluation. METHODS: This retrospective case-control study included 60 glaucomatous eyes that were being treated with topical anti-glaucoma drugs, 30 eyes that underwent laser iridotomy or trabeculectomy, and 60 control eyes. Intraocular pressure, duration of topical anti-glaucoma medications, mean number of topical anti-glaucoma drugs, and preoperative central corneal endothelial cells were analyzed. RESULTS: The numbers of central corneal endothelial cells in the topical anti-glaucoma medication group, the surgical group and the control group were 2681.30 +/- 355.33, 2435.57 +/- 646.81 and 2822.08 +/- 330.17 cells/mm2, respectively. The numbers in the topical anti-glaucoma medication group and the surgical group were significantly lower than that of the control group. The number of central corneal endothelial cells was significantly low in patients with longer duration of disease and in those taking a greater number of topical anti-glaucoma drugs (p = 0.003, p = 0.010) CONCLUSIONS: In glaucoma patients, corneal endothelial cell count is decreased by glaucoma surgery, laser therapy, long-term or multiple topical anti-glaucoma medications. When performing cataract surgery in glaucoma patients, preoperative corneal endothelial evaluation is essential.

Effect of Long Term use of Topical Antiglaucoma Medications on Aqueous Humor in Rabbits

Various studies have been performed to identify change in the constituents of aqueous humor which was suggested either as a factor for fibroblast proliferation causing glaucoma filtering bleb failure or as a factor for the pathogenesis of primary open angle glaucoma. This study was designed to investigate change of aqueous humor composition after long-term topical antiglaucoma medication. After 16-week instillation of pilocarpine 4% and Betagan(TM) in ten rabbits, aqueous humor was obtained from eight control and eight experimental eyes. Protein bands were identified by SDS-PAGE and gold staining techniques. The density and distribution of these protein bands was significantly different between the two groups. The result of this study may give help for future study of pathogenesis of primary open angle glaucoma and causes of high failure rate after glaucoma filtration surgery in patients on chronic topical antiglaucoma medication.