Abstract
Purpose :
To understand the distribution features of corneal thickness in healthy rabbits and obtain the parameters of thickness in different areas of rabbit’s cornea, so as to provide guidance for studies of human corneal diseases in rabbit eye models.
Methods :
Central corneal thickness (CCT) and peripheral corneal thickness (PCT) of 15 healthy adult New Zealand white rabbits were measured by A-scan ultrasonic pachymeter and optical coherence tomography (AS-OCT). 13 spots in total were chose for measurement including the CCT spot, 8 spots at the cornea margin in the direction of vertical axis, naso-temporal axis, and oblique axes at 45 and 135 degrees, and at 4 paracentral corneal spots at 1/2 radius of the distance between CCT spot and corneal margin at vertical axis, naso-temporal axis) using AS-OCT.
Results :
CCT results showed that the values measured by A-scan ultrasonic pachymeter and AS-OCT were respectively (372.47±20.11)μm and (373.20±20.32)μm in the right eyes and (375.40±20.12)μm and (376.09±20.45)μm in the left eyes. No significant difference was found between the two instruments (P=0.823,P=0.853).
PCT results showed that the measured values of A-scan ultrasonic pachymeter and AS-OCT were (332.53±16.06)μm and (332.79±16.21)μm in the right eyes, and (333.81±20.89) μm and (334.03±20.94)μm in the left eyes, respectively. No significant difference was found between the two groups (P=0.741,P=0.767).
The mean difference between central thickness and peripheral thickness was (41.8±21.9)μm in the right eyes and (47.07±23.27)μm in the left eyes.
The AS-OCT measurements of paracentral corneal thickness were (342.75±20.72) um in the right eye and (338.07±21.63) um in the left eyes.
Conclusions :
Corneal thickness of rabbits is significantly smaller than that of human eyes. Central corneal thickness of rabbits is larger than that of peripheral cornea, which is contrary to the distribution of human corneal thickness. The difference is mainly determined by the density, orientation and distribution of the corneal tissue and collagen fiber layers in the central and peripheral areas. Rabbits are one of the main animal models in ophthalmological research, it is of great significance to establish a mathematical model of rabbit cornea in the study of human corneal diseases.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.