Optic Nerve Head Morphology and Macula Ganglion Cell Inner Plexiform Layer Thickness in Axially Anisometropic Rhesus...

Area of Science:

• Ophthalmology
• Animal Models
• Retinal Imaging

Background:

• Anisometropia, a common refractive error, can lead to differences in eye growth.
• Understanding the impact of axial elongation on ocular structures is crucial for diagnosing and managing visual impairments.

Purpose of the Study:

• To investigate the relationship between axial elongation and the morphology of the optic nerve head (ONH) and inner retinal thickness in the macula.
• To quantify specific ONH and macular parameters in relation to axial length in young rhesus monkeys.

Main Methods:

• Optical coherence tomography (OCT) was used to image the eyes of 26 anisometropic rhesus monkeys.
• Key parameters including Bruch's membrane opening (BMO) area, minimum rim width (MRW), anterior lamina cribrosa surface (ALCS) position, scleral crescent, circumpapillary retinal nerve fiber layer (RNFL), choroid thickness, macula total retinal thickness (mTRT), and ganglion cell inner plexiform layer (GCIPL) thickness were measured.
• Linear regression analysis was performed to correlate OCT measures with axial length and inter-eye differences.

Main Results:

• Axial length was significantly correlated with BMO area, ALCS position, scleral crescent area, choroid thickness, mTRT, and GCIPL thickness (all P < 0.05).
• Regression slopes for these parameters did not differ between the right eye and interocular differences, suggesting consistent effects of axial length.

Conclusions:

• Axial elongation is associated with distinct posterior segment morphological variations in anisometropic rhesus monkeys.
• Further research is needed to determine if these morphological differences elevate the risk of ocular pathology.