Refractive Development and Choroidal Vascularity in the Form-Deprivation Pigmented Rabbit Model

Area of Science:

• Ophthalmology
• Animal Models
• Myopia Research

Background:

• Form deprivation (FD) is a common method to induce myopia in animal models.
• Understanding refractive development and choroidal changes is crucial for myopia research.

Purpose of the Study:

• To assess refractive development and choroidal vasculature changes in a form-deprivation (FD) pigmented rabbit model.
• To investigate the relationship between axial length, choroidal thickness, and choroidal vascularity in myopia progression.

Main Methods:

• Monocular FD was performed in young pigmented rabbits for eight weeks.
• Refractive errors, ocular biometry, retinal thickness, and choroidal thickness were measured using retinoscopy, keratometry, ultrasonography, and OCT.
• Choroidal vascularity index (CVI) was calculated from OCT images.
• Vitreous dopamine levels were measured using ELISA.

Main Results:

• FD eyes developed myopia (approx. -2.00 D) with increased axial length (0.32 mm) and vitreous chamber depth (0.32 mm).
• Choroidal thickness decreased significantly in FD eyes (-19.37 µm), while CVI remained unchanged.
• Vitreous dopamine levels were lower in FD eyes compared to controls.

Conclusions:

• Form deprivation induces myopia and alters ocular parameters in rabbits.
• Choroidal thinning occurs with axial elongation during FD-induced myopia.
• Vitreous dopamine may play a role in myopia development.