Korean J Ophthalmol.  2005 Dec;19(4):281-287. 10.3341/kjo.2005.19.4.281.

Asymmetry Analysis of the Retinal Nerve Fiber Layer Thickness in Normal Eyes using Optical Coherence Tomography

• Park JJ
• Oh DR
• Hong SP
• Lee KW

• KMID: 754440
• DOI: http://doi.org/10.3341/kjo.2005.19.4.281

Abstract

PURPOSE
To investigate the asymmetry of the retinal nerve fiber layer thickness (RNFLT) with respect to the horizontal and vertical meridian and between the right and left eye in normal subjects. METHODS: The RNFLT was measured in 121 normal volunteers by optical coherence tomography (OCT). The RNFLT was analyzed by dividing the circle scanning area (diameter 3.4 mm) around the optic disc into 4 quadrants and 12 sectors. RESULTS: There was a significant difference between the RNFLT of the nasal and temporal quadrant in individual eyes. There was a significant difference between the RNFLT of corresponding sectors with respect to the vertical or horizontal meridian in individual eyes. The nasal and temporal RNFLTs were asymmetrical between the right and left eye in the quadrant and sector analysis. The RNFLT of the nasal and temporal quadrant was thicker in the right eye. The nasal and inferior RNFLT measured by OCT had a significant correlation with degree of refractive error. CONCLUSIONS: In normal subjects without significant anisometropia, there was significant asymmetry of the RNFLT for each eye as well as between the right and left eye.

Keyword

Asymmetry; Early detection of glaucomatous damage; Optical coherence tomography; Retinal nerve fiber layer thickness

MeSH Terms

*Tomography, Optical Coherence
Retinal Ganglion Cells/*ultrastructure
Retina/*cytology
Reference Values
Optic Disk/cytology
Nerve Fibers/*ultrastructure
Male
Humans
Female
Adult

Figure

• 

  Fig. 1 (A) Four 90-degree quadrants of retinal nerve fiber layer thickness measured by a circle scanning diameter of 3.4 mm around the optic disc by OCT in the right and left eyes. S: superior quadrant, I: inferior quadrant, N: nasal quadrant, T: temporal quadrant. (B) Twelve equal 30-degree sectors of retinal nerve fiber layer thickness measured by a circle scanning diameter of 3.4 mm around the optic disc by OCT in the right and left eye.

• 

  Fig. 2 (A) The difference of RNFLT between superior sectors and inferior sectors, symbolized by black and gray shading, respectively, was accepted as statistically significant (p<0.05). RNFLT in the black-colored sector was thicker than RNFLT in the gray-colored sector. Inferior sectors were thicker in those sectors corresponding to the arcuate area, but superior sectors were thicker in the non-arcuate area. (B) The difference of RNFLT between nasal sectors and temporal sectors, symbolized by the black and gray shading, respectively, was accepted as statistically significant (p<0.05). The RNFLT in the black colored sector was thicker than the RNFLT in gray colored sector. The RNFLT of nasal sectors close to the horizontal poles was thicker than that of temporal sectors. The RNFLT of temporal sectors close to the vertical meridian was thicker than that of nasal sectors.

• 

  Fig. 3 The difference in RNFLT between the right and left eye, symbolized by black and gray shading, respectively, was accepted as statistically significant (p<0.05). RNFLT in the black-colored sector was thicker than RNFLT in the gray-colored sector. RNFLT was thicker in the right than the left eye at the nasal and temporal sectors

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