Comparison of Optic Nerve Head and Retinal Nerve Fiber Layer Parameters Derived From Two Different Methods of Scan Alignment

Inclusion criteria

• Able and willing to undergo the test procedures, give consent, and to follow instructions
• Subjects that understand the nature of the trial
• Signed informed consent
• Age : 18 years or older
• For "normal subjects", "normal" means, there is no reason that would prevent imaging of the eye, therefore:
• Self-reported healthy eyes without prior intraocular surgery (except cataract surgery and laser in situ keratomileusis) and without clinically significant vitreal, retinal or choroidal diseases, diabetic retinopathy, or disease of the optic nerve (e.g. impacting central VA or RNFLT measurements as determined by the expertise of the investigator)
• Visual field GHT within normal limits
• For "glaucoma subjects": Early to advanced glaucoma according to existing medical charts and visual field GHT outside normal limits on at least two occasions during the testing.
• Refraction between +6 and -6 diopters spherical equivalent and astigmatism ≤ 2 diopters
• When both eyes are eligible, one randomly selected eye will be evaluated in the analysis

Exclusion criteria

• Vulnerable subjects (as defined in ISO 14155 GCP)with the exception of employees of the site, and , if applicable, students of the respective university. Staff that is directly involved in the study is excluded from participation.
• subjects unable to read or write
• Unreliable visual field. The reliability indices should be used as guide as well as the perimetrist's notes.
• Unusable disc stereo photos.
• Inability to undergo the tests.
• Insufficient quality of Spectralis OCT images (this is not determined until after Spectralis OCT examination, and is an unusual circumstance).

Minimum requirements are:

• Retina completely included in image frame,
• Quality Score ≥ 20 in the stored ART mean images, and
• For ONH-R scan: Center position error ≤ 100 μm.
• Note: Inability of a subject to perform one of the two scan patterns or insufficient image quality in one scan pattern does not exclude the subject or eye from the study.