THE IMPACT OF MINIMALLY INVASIVE GLAUCOMA SURGERY ON THE OCULAR SURFACE AND QUALITY OF LIFE IN PATIENTS WITH GLAUCOMA.

To explore the impact of minimally invasive glaucoma surgery (MIGS) on patient-reported outcomes and clinical parameters related to ocular surface disease in people with glaucoma.This study evaluates changes in quality of life following internal MIGS using iStent combined with phacoemulsification, with or without adjunctive ECP, and measures the extent to which the procedure reduces complaints related to ocular surface discomfort

A prospective cohort study conducted at Queen Victoria Hospital, NHS Foundation Trust, East Grinstead, United Kingdom.

Fifty-seven patients underwent cataract surgery combined with trabecular bypass surgery with the iStent inject® W (Glaukos, San Clemente, California, USA) which involved implanting two preloaded trabecular micro-bypass stents. This was combined, when clinically appropriate, with endoscopic cyclophotocoagulation (Beaver-Visitec International, Waltham, Massachusetts, USA). Patients were examined prior to undergoing iStent combined with phacoemulsification with or without adjunctive endocyclophotocoagulation and at 12-month follow-up.

 All participants attended a baseline study visit 2-4 weeks prior to surgery. Clinical measurements at this visit included Snellen visual acuity, IOP using Goldmann Applanation Tonometry (GAT), Oxford Corneal grading scheme, tear film break-up time (TBUT), and tear film osmolarity using Tear Lab

In addition to baseline and follow-up eye examinations, all participants completed PROMs (Patient Reported Outcome Measures) questionnaires, which were all performed by the same investigator, pre and post operatively, to enable data on ocular and functional complaints to be systematically captured. The PROMs used in the study were as follows.

• European Quality of Life in 5 Dimensions (EQ-5D)
• Glaucoma Quality of Life-15 (GQL-15)
• Glaucoma Symptom Severity Scale (GSS)
• Ocular Surface Disease Index (OSDI)

At 12 months of follow-up, on average patients returned statistically significantly improved scores on glaucoma-specific (GQL-15, p=<0.001; GSS, p=<0.001), general health (EQ5D, p=0.02) and ocular surface PROMs (OSDI, p=0.001). Patients were using fewer eye drops on average after MIGS compared to before surgery (1.1 ± 0.9 versus 1.8 ± 0.8; p = <0.001). Undergoing MIGS was associated with improved tear film break-up time (p = <0.001) and reduced corneal fluorescein staining (p = <0.001).

Glaucoma patients undergoing minimally invasive glaucoma surgery with phacoemulsification with or without adjunctive endocyclophotocoagulation had statistically significantly improved general and glaucoma-related quality of life and ocular surface measurements 12-months post-operatively. Quality of life and clinical parameters related to the ocular surface are improved following MIGS combined with phacoemulsification in patients previously treated with anti-glaucoma therapy.