Effect of steroid eyedrops after trabeculectomy in glaucoma patients: a keratograph analysis

To investigate the use of preoperative steroid eyedrops in glaucoma patients undergoing trabeculectomy for ocular surface disease.

A total of 31 eyes of 31 glaucoma patients were included. Only glaucoma patients who had been using at least three topical intraocular pressure-lowering medications for longer than 6 months were included. All patients were treated with loteprednol etabonate ophthalmic suspension 0.5% four times per day for 1 week before trabeculectomy. Data from baseline (day of surgery) and the follow-up visit (2 weeks after surgery) were included. All patients underwent a detailed ophthalmologic examination. Ocular surface disease was evaluated using the Ocular Surface Disease Index questionnaire and clinical measures, including tear breakup time, conjunctival hyperemia, and biomicroscopy to detect the presence or absence of keratitis. Ocular Surface Disease Index scores greater than 13 indicated a clinically relevant presence of ocular surface disease. In addition, all patients underwent keratograph analysis. The comparison of ocular surface disease before and after trabeculectomy was assessed using a paired test.

The mean age of the glaucoma patients was 69.90 ± 10.77 years. The average visual acuity was 0.40 ± 0.34 logMAR. The overall Ocular Surface Disease Index prevalence rate was 27.20 ± 17.56 units. Clinical assessment revealed no significant difference in bulbar redness, breakup time, or keratitis before and after surgery (p>0.05 for all comparisons). Keratograph analysis showed that the only two parameters that were significantly different before and after trabeculectomy ewere the bulbar redness by keratograph (BR-K) and the average noninvasive tear breakup time. Patients presented more conjunctival hyperemia and shorter noninvasive tear breakup time after trabeculectomy as compared with before surgery (p=0.013 and p=0.041, respectively).

The present study not only confirms the high prevalence of clinical findings of ocular surface disease in glaucoma patients but also reveals new objective parameters measured by keratograph analysis. Apart from using loteprednol etabonate ophthalmic suspension 0.5% 1 week before the surgery, our sample presented a worsening of conjunctival hyperemia (bulbar redness by keratograph) and also a shorter noninvasive tear breakup time postoperatively.