Factors determining the peripapillary retinal nerve fiber distribution

Area of Science:

• Ophthalmology
• Retinal Imaging
• Optometry

Background:

• The distribution of the peripapillary retinal nerve fiber layer (RNFL) is crucial for diagnosing optic neuropathies.
• Understanding factors influencing RNFL thickness is essential for accurate interpretation of imaging data.

Purpose of the Study:

• To investigate the impact of retinal vessel arrangement and ocular biometrics on peripapillary RNFL distribution.
• To identify key ocular features that correlate with RNFL thickness patterns.

Main Methods:

• Fifty normal eyes underwent spectral-domain optical coherence tomography (SD-OCT) and fundus photography.
• Measurements included axial length, central corneal thickness, interpeak RNFL distance, inter-vessel angle, and optic disc-foveola distance.
• Correlation and multiple regression analyses were performed to assess relationships between ocular factors and RNFL distribution.

Main Results:

• Longer axial length and a smaller angle between superior temporal (ST) and inferior temporal (IT) retinal veins were associated with increased interpeak RNFL distance.
• Multiple regression analysis confirmed that the inter-vessel angle and central corneal thickness significantly influenced interpeak RNFL distance.

Conclusions:

• A decreasing angle between the IT and ST veins, thinner central corneal thickness, and increasing axial length contribute to greater separation of RNFL peaks.
• The inter-vessel polar angle is a significant determinant of RNFL thickness peak location.
• These findings may aid in optimizing normative data for peripapillary RNFL assessment.