Influence of Large Intraocular Pressure Reduction on Peripapillary OCT Vessel Density in Ocular Hypertensive and Glaucoma Eyes.

BACKGROUND/PURPOSE: Optical coherence tomography (OCT) angiography is a new noninvasive method to measure peripapillary microcirculation in various retinal layers, separately. In this case series, we investigate whether large medical intraocular pressure (IOP) reduction (>50% of the untreated baseline value) to IOP≤18 mm Hg influences peripapillary angioflow density (PAFD, percentage of the analyzed retinal area) in the retinal nerve fiber layer in high pressure (IOP≥35 mm Hg) ocular hypertensive and glaucoma eyes.

METHODS

The AngioVue OCT (software version 2015.100.0.33) was used for PAFD measurements in 6 eyes of 4 consecutive newly detected young patients (age: 32 to 45 y; 2 ocular hypertensive and 4 pigment dispersion/glaucoma eyes). PAFD was measured on high quality images (signal strength index >50) at untreated baseline and 2 to 4 weeks later when the IOP was medically reduced. The PAFD measurements were immediately followed by IOP measurements.

RESULTS

Untreated and under treatment IOP ranged between 35 and 42 mm Hg, and 12 and 18 mm Hg, respectively (IOP decrease >50% in all cases). Peripapillary PAFD increased in all cases, in 5 cases the increase was greater than the baseline value plus 2 test-retest variability determined earlier by us on glaucoma eyes.

CONCLUSIONS

The results suggest that large medical IOP reduction may result in clinically significant increase of peripapillary capillary perfusion in the retinal nerve fiber layer in young individuals with high untreated IOP. To evaluate the clinical usefulness of OCT angiography in the management of glaucoma detailed prospective clinical studies are necessary.