Why carry out this study?

Topical glaucoma medications are widely known to cause or worsen ocular surface disease, while trabecular micro-bypass stent implantation with iStent or iStent inject is proven to consistently reduce medication burden and intraocular pressure (IOP) in glaucomatous eyes.

This prospective cohort study is one of the first to examine the direct linkage between stent implantation with phacoemulsification and postoperative changes in ocular surface disease.

Specifically, this 3-month study measured the Ocular Surface Disease Index score (OSDI), corneal/conjunctival staining (Oxford Schema), fluorescein tear break-up time (FTBUT), conjunctival hyperemia (Efron Scale), glaucoma medications, and IOP.

What was learned from the study?

Implantation of iStent or iStent inject with cataract surgery produced meaningful improvements in all measures of ocular surface health, alongside significant reductions in IOP and medications.

Specifically, mean OSDI score improved from 40.1 (severe) to 17.5 (mild) (p < 0.0001), with a ~2.5-fold decrease in the proportion of eyes with moderate/severe OSDI and a ~6-fold increase in the proportion of eyes with normal OSDI. Mean FTBUT increased from 4.3 to 6.4 s (p < 0.0001); mean Oxford corneal/conjunctival staining reduced from 1.4 to 0.4 (p < 0.0001); mean Efron conjunctival hyperemia reduced from 1.4 to 1.2 (p = 0.118).

Meanwhile, the mean number of glaucoma medications decreased from 1.5 to 0.6 medications (p < 0.0001); mean IOP reduced from 17.4 to 14.5 mmHg (p < 0.0001); the safety profile was excellent.