Form-deprivation myopia in the guinea pig (Cavia porcellus)

Abstract

Form deprivation (FD) was induced in 61 guinea pigs with a diffuser worn on one eye. The form-deprived eye elongated and developed myopia within 6 days in animals raised under a 12:12 h light/dark cycle, but not when reared in darkness. After 11 days of FD, the average eye was -6.6 D more myopic and 146 microm longer than its fellow eye. Initially the myopia was mostly from vitreous chamber elongation, but with longer periods of FD, corneal power increases predominated. These effects were confirmed in schematic eyes. After a delay, FD also elongated the vitreous chamber of the non-deprived eye. The myopia rapidly abated once the diffusers were removed (65% within 24 h) due to inhibition of elongation and choroidal thickening. The guinea pig provides a fast mammalian model of FD myopia and corneal curvature regulation.

Three-dimensional OCT based guinea pig eye model: relating morphology and optics

“…The guinea pig develops deprivation myopia in a short period of time [4] with independent growth in different retinal hemifields [29] and responds to lensinduced blur [30].…”

“…Additionally, longitudinal studies of myopia development can occur within a much shorter time period than in humans. The guinea pig has been established as an effective myopia model, and stands as a common myopia model in Asian research labs today [4]. It is a mammal, shows a rapid ocular development, responds to lens-induced blur, is easy to raise and handle, and optical measurements are feasible.…”

“…We have previously reported optical aberration measurements (using Hartmann Shack wavefront sensors) in other animal models, such as chickens [5,6], marmosets [7], macaques [8] and mice [9]. However, despite the increasing use of the guinea pig model, and extensive research on the regulation of its eye growth (in terms of axial length and refractive error) [4,10,11], there is scarce information on its optical properties in vivo.…”

Worldwide prevalence and risk factors for myopia

“…83 Another early study on chicks found that monocular deprivation of form vision also produced myopia and eye enlargement. 84 These landmark studies ushered a new era in experimental myopia study and in the years since, models of form deprivation of myopia have been developed in a wide variety of animal species, including chicks, 85,86 tree shrews, 87,88 guinea pigs 89,90 and adult monkeys. 91 Other experimental methods using positive or negative lens as modulators of refractive error in chicks showed that the eye grows more slowly (developed hyperopia) or more rapidly (developed myopia), respectively.…”

Gene Expression and Pathways Underlying Form Deprivation Myopia in the Guinea Pig Sclera

“…Form deprivation was induced with a translucent diffuser as previously described, 22 and diffusers were cleaned and checked daily. At the end of 2 weeks, one drop of 1% cyclopentolate (Cyclogyl; Alcon, Macquarie Park, Australia) was topically applied to each eye and after 1.25 to 1.5 hours, the refractive error was measured using an infrared autorefractor (AR-20Nidek; Gamagori, Aichi, Japan).…”