Purpose
To screen glaucoma patients using spectral-domain optical coherence tomography (SD-OCT) in an elderly population
Methods
The ALIENOR (Antioxydants, Lipides Essentiels, Nutrition and maladies OculaiRes) Study is a population-based epidemiological study on age-related eye diseases. In 2009-2010, 535 subjects, aged 75 years or more, had an eye examination, including intraocular pressure, central corneal thickness (CCT) measurements. Glaucoma diagnosis was made using retinophotography of the optic nerve head and ISGEO (international society for epidemiologic and geographical ophthalmology) criteria. A measurement of retinal nerve fiber layer (RNFL) thickness using spectral- domain optical coherence tomography (Spectralisâ, Heidelberg engineering, Heidelberg, Germany) was performed. Global and sectorial RNFL thicknesses were analyzed and compared between glaucomatous patients and controls.
Results
The mean age was 82.2+/-4.2 years and 40 subjects (7.47%) had a glaucoma diagnosis. Global RNFL thickness was significantly lower in the glaucoma group (65.4+/-14.4m) than in the control group (88.2+/-13.0m) (p<0.001). Area under the receiving operating curve was higher for the global RNFL thickness (0.886), followed by the infero-temporal (0.867), the supero-temporal RNFL sector (0.857) and the infero-nasal sector (0.800) respectively. When combining Global, supero-temporal and infero-temporal RNFL thicknesses and taking into account the 5% threshold provided by the database of the machine, sensitivity was 65.0%, specificity was 91.9%, positive predictive value was 39.4% and negative predictive value was 97.0%.
Conclusions
Global RNFL thickness is the most accurate parameter to screen glaucoma followed by both temporal sectorial RNFL thicknesses. These findings are consistent with the pathophysiology of glaucoma disease. SD-OCT is a fast and non-contact high resolution imaging system widely used by ophthalmologists in current clinical practice. This machine may be of interest to screen glaucoma in an elderly population.