Relationship Between Optic Nerve Appearance and Retinal Nerve Fiber Layer Thickness as Explored with Spectral Domain Optical Coherence Tomography.
OBJECTIVE
To study the relationship between the appearance of the optic nerve and the retinal nerve fiber layer (RNFL) thickness determined by spectral domain optical coherence tomography (OCT).


METHODS
Records from patients with spectral domain-OCT imaging in a neuro-ophthalmology practice were reviewed. Eyes with glaucoma/glaucoma suspicion, macular/optic nerve edema, pseudophakia, and with refractive errors > 6D were excluded. Optic nerve appearance by slit lamp biomicroscopy was related to the RNFL thickness by spectral domain-OCT and to visual field results.


RESULTS
Ninety-one patients (176 eyes; mean age: 49 ± 15 years) were included. Eighty-three eyes (47%) showed optic nerve pallor; 89 eyes (50.6%) showed RNFL thinning (sectoral or average peripapillary). Average peripapillary RNFL thickness in eyes with pallor (mean ± SD = 76 ± 17 μm) was thinner compared to eyes without pallor (91 ± 14 μm,P< 0.001). Optic nerve pallor predicted RNFL thinning with a sensitivity of 69% and a specificity of 75%. Optic nerve appearance predicted RNFL thinning (with a sensitivity and specificity of 81%) when RNFL had thinned by ∼ 40%. Most patients with pallor had RNFL thinning with (66%) or without (25%) visual field loss; the remainder had normal RNFL and fields (5%) or with visual field abnormalities (4%).


CONCLUSIONS
Optic nerve pallor as a predictor of RNFL thinning showed fair sensitivity and specificity, although it is optimally sensitive/specific only when substantial RNFL loss has occurred.


CONCLUSIONS
Finding an acceptable relationship between the optic nerve appearance by ophthalmoscopy and spectral domain-OCT RNFL measures will help the clinician's interpretation of the information provided by this technology, which is gaining momentum in neuro-ophthalmic research.
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Tomas S
TS
Aleman
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA ; Center for Preventive Ophthalmology and Biostatistics, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Jiayan
J
Huang
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Sean T
ST
Garrity
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Stuart B
SB
Carter
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Wendy D
WD
Aleman
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA ; Center for Preventive Ophthalmology and Biostatistics, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Gui-Shuang
GS
Ying
Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
Madhura A
MA
Tamhankar
nerve fiber layer; optic nerve pallor; optical coherence tomography