A Study Assessing How Impaired Blood Flow to the Eye is Involved in Glaucoma

Overview

Status: Recruiting
Keywords: Glaucoma
IRB Number: 00056436
Specialty: Ophthalmology, Ophthalmology
Sub Specialties: Glaucoma, Comprehensive Ophthalmology

Brief Summary

 

Our study will seek to determine if there is correlation between the progression of glaucoma in specific glaucoma subset groups and vascular parameters in the eye, more specifically the choroid. To achieve this we will look at measurements relating to vascular parameters in the eye in three different subsets of subjects, primarily: normal tension glaucoma (NTG), primary open angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXF) subjects and healthy individuals. We will primarily examine intraocular pressure (IOP), choroidal thickness and ocular pulse amplitude (OPA) among the patient groups, along with blood pressure, ocular perfusion pressure (OPP), heart rate, contrast sensitivity and multifocal electroretinograms. Correlations will be assessed between variables as well as between the subset of glaucoma patient groups to assess trends. Our hypothesis is that the glaucomatous patients will have alterations in these vascular parameters and functional endpoints that either correlate with the type of glaucoma and or the severity of the optic neuropathy.

We will analyze this link by measuring choroidal thickness, calculated OPP and OPA, using some of the most advanced techniques and equipment available in the field of ophthalmology research. Correlations will be assessed between variables as well as between the subset of glaucoma patient groups to assess trends. The aim of this study is to help to further the understanding of ocular blood flow and vascular parameters in glaucoma.

Principal Investigator: Kevin Garff
Department: Ophthalmology
Co Investigator:

Contact Information

Name:Barbara Wirostko
Phone: 587-3020
Email: barbara.wirostko@hsc.utah.edu

Inclusion Criteria

 

All eligible subjects will be ≥40years old and have best corrected visual acuity of  ≥20/40 and open angles of at least a grade 2 on gonioscopy and or a patent peripheral iridotomy.

Glaucoma patients may be included regardless of whether they are on topical IOP lowering medications and or if they have had laser and or surgical procedures for their glaucoma.

 

Normal subjects will be IOP ≤ 21 mmHg, and normal ophthalmoscopic appearance of the optic nerve (cup-to-disc ratio < 0.5 in either eye, cup-to disc ratio asymmetry < 0.2, absence of hemorrhage and localized or diffuse rim thinning) and a normal HVF.

 

Glaucoma subjects will be included if they have an established diagnosis of primary open angle glaucoma, or pseudoexfoliation (PXF) glaucoma made by a glaucoma specialist. This diagnosis will be based on a glaucomatous optic disc damage and an abnormal visual field test result consisting of pattern standard deviation and/or glaucoma hemifield test results outside normal limits. At least two consecutive visual field examinations will be required, with the most recent test performed within 12 months of enrollment. Subjects will be further classified as having mild (MD > -6 dB), moderate (MD -12 dB  ≤ MD  ≤ -6 dB) or severe glaucoma (MD < -12 dB) based on standard HVF and AGIS criteria. Normal tension glaucoma will be diagnosed in the presence of repeatable IOP ≤ 21  mmHg (without medications), glaucomatous optic disc changes, and visual field loss. The criteria to determine if a subject can be included in the PXF glaucoma group will include: the presence of pseudoexfoliation material on the lens capsule or near the pupil; transillumination defects near the pupil; increased pigmentation or pseudoexfoliation material at the angle, or both; an intraocular pressure of more than 21 mmHg without treatment; typical glaucomatous optic nerve changes; and glaucomatous visual field defects 

Note: The study will first enroll 3 groups (Healthy volunteers, POAG and NTG), and will study PXF subjects if time and resources permit.

 

Exclusion Criteria

Exclusion criteria will include any retinal or neuro-ophthalmologic disease, ocular trauma, history of retinal detachment, ocular tumor, previous photodynamic therapy, amblyopia, intraocular surgery during the previous 6 months, secondary glaucoma, and active, chronic, or recurrent uveitis or retinal pathology that could affect the results of the SD OCT. Subjects with long axial length and high myopia ≥-6 diopters or axial length ≥26.5 mm; subjects who have had medication changes that could affect their blood pressure or heart rate within the last month and; any subject for whom the medical monitor feels a underlying system disease and or condition may compromise the ability to get reliable data.