Evaluation of Blood Flow Regulation With Laser Speckle Flowgraphy

Evaluation of Blood Flow Regulation With Laser Speckle Flowgraphy in Patients With Normal Tension Glaucoma and Healthy Individuals.

The study includes Caucasian patients with diagnosis of normal tension glaucoma and age- and sex-matched healthy individuals. Measurements of optic nerve head blood flow will be performed with laser speckle flowgraphy (LSFG). Also, the intraocular pressure (IOP), systolic and diastolic blood pressure, heart rate (HR), mean arterial pressure (MAP) as well as ocular perfusion pressure (OPP) will be evaluated. After baseline measurements individuals will be asked to ingest 800 ml of water in less than five minutes. Measurements will be repeated after 15, 30 and 45 minutes.

Inclusion Criteria:

• presence of glaucomatous optic disc changes in biomicroscopy and visual field defects or abnormal circumpapillary retinal nerve fibre layer (RNFL) thinning (evaluated by OCT as defined by the on-board software)
• IOP ≤ 21mmHg without therapy
• normal open angle in a gonioscopic examination
• age > 40 years

Exclusion Criteria:

• IOP > 21 mmHg in patients' history
• ametropia > 6 diopters
• cataract with severity greater than grade 2 of the lens opacities classification system (LOCS) classification
• presence of corneal opacities
• uncontrolled hypertension with systolic blood pressure (SBP) > 165mmHg and/or diastolic blood pressure (DBP) > 100mmHg