The purpose of this trial is to evaluate the performance of a new diagnostic device in the diagnosis and management of glaucoma. We will use this new device (PERG) to evaluate the function of the retina in glaucoma patients. This device is safe for the patients.

Glaucoma is one of the leading causes of blindness worldwide. It's an optic neuropathy characterized by the progressive death of retinal ganglion cells.

In laboratories, it's possible to measure the electrical activity of retinal ganglion cells (RGC). Some researchers found that RGC showed electrical anomalies before dying. This decrease of electrical activity can be measured by using pattern electroretinography (PERG). Unfortunately, these measures could not be obtained in clinics before this new device.

For this reason, Diopsys developed a new device that can measure PERG directly in clinics, allowing physicians to have these data earlier to help them diagnose pathologies such as glaucoma or other ganglion cells abnormalities.

Currently, it is known that glaucoma is difficult to diagnose in the early stages and it's challenging to decide when to start a treatment.

In this study, our purpose is to use this new device to evaluate its efficacy in the diagnosis and management of glaucoma.

Inclusion Criteria:

• Glaucoma (all types of glaucoma);
• Ocular hypertensive (Suspicion of glaucoma);
• Control Patients (without any suspicion/sign of glaucoma);
• Have given written informed consent, prior to any investigational procedures;
• Aged 18 years of either sex.

Exclusion Criteria:

• Patients not able to understand the character of the study
• Participation in other clinical research within the last 4 weeks
• Other diseases that may cause visual field loss or optic disc abnormalities
• Systemic diseases that may affect PERG amplitude such as diabetes, parkinsonism, multiple sclerosis
• Poor best corrected visual acuity outside the limits recommended for the test
• Patients with high myopia (>5D)

All patients will be enrolled from glaucoma clinics of the Montchoisi glaucoma center