Quantification of retinal nerve fiber layer thickness in normal eyes, eyes with ocular hypertension, and glaucomatous eyes with SD-OCT.
OBJECTIVE
To quantitatively evaluate and compare retinal nerve fiber layer (RNFL) thickness between normal eyes, eyes with ocular hypertension (OHT), and glaucomatous eyes in an Indian population using spectral domain optical coherence tomography (SD-OCT).


METHODS
Average and quadrant RNFL values were compared among three groups (66 normal eyes, 55 OHT eyes, and 51 glaucomatous eyes) and the discriminating power of each parameter was evaluated by calculating areas under receiver operator curves (AROCs).


RESULTS
The mean RNFL thickness was 93.45 ± 16.9 μm in glaucomatous eyes, significantly less than in normal (112.48 ± 6.8 μm) and OHT (110.09 ± 10.9 μm) eyes. OHT eyes had significantly thinner RNFL thickness in the temporal quadrant (P = .006) than normal eyes. RNFL thickness in glaucomatous eyes differed significantly from normal eyes in most parameters except nasal quadrant (P = .1) and from OHT eyes in most parameters except temporal (P = .4) and nasal quadrants (P = .3). The parameter with the largest AROC to discriminate between OHT and normal eyes was temporal quadrant (0.65). Inferior quadrant RNFL thickness had the largest AROC (0.93) to distinguish between OHT and glaucomatous eyes and normal and glaucomatous eyes.


CONCLUSIONS
SD-OCT identified differences in most parameters between eyes with glaucoma and normal eyes and also between eyes with glaucoma and OHT. Overlap of RNFL thickness between normal and OHT eyes limits the ability of this instrument to differentiate between normal and OHT subjects.
Department of Glaucoma, Pushpagiri Eye Institute, 241 Uma Plaza, Road No. 9, West Marredpally, Secunderabad, Andhra Pradesh, India. tarannummansoori@yahoo.com
Tarannum
T
Mansoori
Kalluri
K
Viswanath
Nagalla
N
Balakrishna
D000328:Adult; D000368:Aged; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009798:Ocular Hypertension / Q000175:diagnosis*; D009898:Optic Disk / Q000166:cytology / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis; D011446:Prospective Studies; D012372:ROC Curve; D012016:Reference Values; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000473:pathology*; D041623:Tomography, Optical Coherence