# Direct Measures of Retinal Blood Flow and Autoregulation as Robust Biomarkers for Early Glaucoma

> **NIH NIH R01** · UNIVERSITY OF MARYLAND BALTIMORE · 2022 · $316,677

## Abstract

Project Summary:
There is strong evidence for a vascular component in the development and progression of
primary open angle glaucoma (POAG). Specifically, glaucoma is associated with impaired
retinal blood flow (RBF) and autoregulation of RBF. Autoregulatory impairment may precede
retinal ganglion cell (RGC) loss and has been proposed as a potentially early, reversible
biomarker. The rationale underlying this proposal is that highly precise and accurate, direct
measures of RBF are necessary to study dynamic changes in RBF and their effect on RGCs.
Current methods of quantifying RBF remain limited as the majority of imaging modalities provide
indirect, relative measurements of RBF. We will directly measure RBF using two robust direct
measures: erythrocyte mediated angiography flowmetry (EMAf) and multimodal adaptive optics
(mAO). Both techniques allow for the highly accurate and precise measurement of RBF down to
the capillary level in the human eye in vivo. We hypothesize that these direct measures of
determining absolute RBF will show impaired autoregulation of microvascular RBF in early
glaucoma and that this will correlate with glaucomatous damage. Our research program will test
this hypothesis through two specific aims. In Specific Aim 1, we will determine the extent of
impaired autoregulation associated with early glaucoma and measure its ability to predict further
glaucoma damage. In Specific Aim 2 we will determine the relationship of capillary density and
RGC density in glaucoma subjects and controls. We predict that early glaucoma subjects will
exhibit significant measurable impaired vascular autoregulation as compared to controls and
that local changes in these parameters will predict structural glaucomatous deficits.

## Key facts

- **NIH application ID:** 10478084
- **Project number:** 5R01EY031731-02
- **Recipient organization:** UNIVERSITY OF MARYLAND BALTIMORE
- **Principal Investigator:** Osamah Jawaid Saeedi
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $316,677
- **Award type:** 5
- **Project period:** 2021-09-01 → 2026-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10478084

## Citation

> US National Institutes of Health, RePORTER application 10478084, Direct Measures of Retinal Blood Flow and Autoregulation as Robust Biomarkers for Early Glaucoma (5R01EY031731-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10478084. Licensed CC0.

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