Investigation of Neurovascular Coupling in Glaucoma Patients and Healthy Subjects

Inclusion criteria Patients with primary open angle glaucoma * Diagnosis of manifest primary open angle glaucoma defined as pathological optic disc appearance * Glaucoma hemifield test outside normal limits * Untreated IOP ≥ 21 mmHg on at least three measurements in the medical history * Mean deviation in the visual field test is less than or equal 10dB (for one group) OR more than 10dB (for the other group) Patients with normal tension glaucoma * Diagnosis of manifest normal tension glaucoma defined as pathological optic disc appearance * Glaucoma hemifield test outside normal limits * No evidence of untreated IOP \> 20 mmHg in the medical history * Mean deviation in the visual field is less than or equal 10dB (for one group) OR more than 10dB (for the other group) Patients with ocular hypertension * Normal ophthalmic findings except presence of ocular hypertension defined as untreated IOP ≥ 21 mmHg on at least three measurements in the medical history * No signs of glaucomatous damage in the optic disc * or the glaucoma hemifield test Healthy control subjects * Normal ophthalmic findings * IOP \< 20 mmHg on least three measurements * No evidence of increased IOP in the medical history * No signs of glaucomatous damage in the optic disc * or the glaucoma hemifield test Exclusion criteria * History of a severe medical condition as judged by the clinical investigator * Abuse of alcoholic beverages * Smoker * Participation in a clinical trial in the 3 weeks preceding the study * Exfoliation glaucoma, pigmentary glaucoma, history of acute angle closure * Intraocular surgery within the last 6 months * Ocular inflammation or infection within the last 3 months * History of epilepsia * Diabetes mellitus * Untreated hypertension with systolic blood pressure \> 160 mmHg, diastolic blood pressure \> 95 mmHg * Pregnancy * Planned pregnancy or lactating