iStent inject Reduces Glaucoma Eye Drop Dependence: Study

In order to obtain an accurate unbiased result of the comparison between surgical treatment and medication, the researchers chose to perform the trial as a prospective, single center contralateral eye study. The subjects selected for the study had bilateral open angle glaucoma that varied from mild to moderate. In the study, the patients themselves functioned as their own controls, as one of their eyes was randomly selected as the study eye that received the micro-invasive surgical procedure, while the other eye acted as the control eye that continued its existing regimen of ocular hypotensive drugs.

As is typical of most clinical practices, slightly more than half of the surgical as well as control eyes had undergone a standard phacoemulsification cataract surgery. Evaluations of various parameters of ocular surface were performed at baseline as well as 1, 3, and 6 months after surgery using both clinical tests as well as validated questionnaires, like the Ocular Surface Disease Index (OSDI) questionnaire and SPEED II score.

Key findings:

• Indeed, the formal statistics of the evaluation of 56 eyes altogether over the course of 6 months yielded concrete figures highlighting an extremely marked differentiation between the intervention and medical management approach in question.
• The number of drugs used daily by patients in the stents group decreased noticeably to the level of 0.4 ± 0.6 medications per day compared to 1.9 ± 1.0 before surgery (p < 0.001) at the 6-month follow-up point.
• However, this was not the case in regard to the medically managed control eyes, where the number remained unchanged at the level of 1.5 ± 0.9 versus 1.4 ± 0.8 drugs (p = 0.168).
• Structurally speaking, the stents group showed significant improvement in two measures as follows: 1) decrease in keratograph bulbar redness to the level of 2.0 ± 0.4 from the baseline of 2.4 ± 0.6 (p = 0.003) and 2) decline in the Oxford ocular surface staining (OSS) score to the level of 0.7 ± 1.0 from the baseline of 1.6 ± 1.2 (p < 0.001).
• In contrast, no statistically significant improvements were observed for the tissue markers in the eyes treated medically.
• Overall, the differences observed in the improvement of both bulbar hyperemia and corneal/ocular surface staining were statistically significantly higher in the stent group eyes (p = 0.005 and p = 0.045, respectively).
• Patient self-reports revealed an overall improvement in their dry eye symptoms following surgery, as evidenced by the reduction in OSDI scores from 18.4 ± 16.4 to 9.3 ± 8.9 (p = 0.007) and in SPEED II scores from 8.0 ± 7.8 to 4.5 ± 4.1 (p = 0.005).

Overall, it can be concluded that interventional glaucoma management through trabecular micro-bypass stent surgery led to decreased medication load, leading to an improvement in the signs and symptoms of OSD. Interventional procedures performed in test eyes yielded superior results compared to fellow eyes undergoing only topical treatment. The findings of this contralateral eye investigation are invaluable in modern ophthalmology, confirming the vast advantages of surgical bypass techniques over simple pressure management techniques.

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