The Study
Effect of intraocular pressure control on visual field progression in the HORIZON trial.
This study looked at how eye pressure changes after surgery and saw that people with lower pressure after surgery tended to have slower vision loss. But it didn’t make the pressure change — it just watched what happened. So we can’t say lower pressure caused the better outcome, only that they went together.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
When people with glaucoma and cataracts get a tiny stent during cataract surgery, their vision declines slower — but not because of sudden pressure spikes after surgery.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 566 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — slowing vision loss by nearly half over five years is a big deal for maintaining independence and quality of life.
- 2The stent group had 44.6% slower vision loss over 5 years.
- 3This benefit disappeared when researchers looked at long-term average pressure (WO-MIOP), but not when they looked at short-term spikes.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Ophthalmology. Glaucoma
Year
2026
Authors
Giovanni Montesano, G. Ometto, Iqbal Ike K Ahmed, G. Gazzard
Related Content
Claims (6)
Higher pressure inside the eye directly increases the chance of damage to the optic nerve, and lowering that pressure reduces the risk of such damage.
In patients with glaucoma and cataract, consistently lower eye pressure over five years is linked to slower loss of peripheral vision, and each standard deviation increase in average eye pressure is associated with a 44.6% faster rate of vision loss.
Patients with glaucoma and cataract who receive the Hydrus Microstent during cataract surgery experience a 44.6% slower decline in their peripheral vision over five years compared to those who receive cataract surgery alone. This difference cannot be fully accounted for by lower eye pressure alone.
A temporary rise in eye pressure on the first day after cataract surgery does not explain why patients with the Hydrus Microstent have different long-term changes in their peripheral vision compared to patients who had cataract surgery alone.
Measuring eye pressure after filtering out short-term fluctuations better predicts long-term vision loss in glaucoma than standard eye pressure readings.
When intraocular pressure is accounted for, the Hydrus Microstent does not produce a different rate of visual field decline compared to cataract surgery alone, meaning its impact on vision preservation is due to lowering eye pressure.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.