Reproducibility of RNFL and ONH Measurements in OAG With Heidelberg Spectralis SD-OCT Glaucoma Module Premium Edition

The purpose of this study is to assess and compare the repeatability of SD-OCT (Spectralis™ OCT, Version 6.0, Heidelberg Engineering, Germany) RNFL thickness measurements with the new software (method B) and with the previous method of measurement (method A) in patients with glaucoma.

It is a prospective, not blinded, not randomised, monocentric study. Inclusion of 50 patients with a diagnosis of primary open angle glaucoma (POAG), that will be recruited from the ophthalmology outpatient department of the UniversityHospital Zurich, Switzerland. All patients will undergo a full ophthalmic examination including measurement of refraction, best corrected visual acuity, examination of anterior and posterior compartment and measurement of the intraocular pressure. On the same day they will have 3 OCT examinations with a new method of measurement (method B).On the same day the first 10 patients will undergo also 3 OCT examinations with the previous method (method A) and they will get an other 3 OCT examinations with method B by a second observer. For this 10 patients the next consultation (3 months +/- 1 month) the 3 OCT examinations with method B will be repeated by the first observer.

Primary objectives are coefficient of variations (COV) of method A and B; Intra-class-correlations (ICC) of method A and B.

Inclusion criteria

• diagnosis of POAG glaucoma
• male and female patients aged 18 years or older, no upper limit
• written informed consent
• visual acuity of more or equal to 0.5 Snellen
• refractive error between + /- 6.00 D spheric and under or equal than 2.00 D cylindrical

Exclusion criteria

• history of surgery other than uncomplicated cataract surgery
• disease affecting cornea, anterior compartment, lens, vitreous body
• history of severe ocular disease, particularly diseases affecting the optic nerve, other than glaucoma
• history of ocular trauma