title: Illumination with monochromatic long-wavelength light promotes myopic shift and ocular elongation in newborn pigmented guinea pigs.
abstract: The purpose of this study was to determine whether long-wavelength light (760 nm) promotes myopic shift in newborn guinea pigs during eye development. Newborn guinea pigs were raised in different types of illumination: long-wavelength light, mixed-wavelength light, and normal light. The guinea pigs that received long-wavelength light were raised in the illumination of long-wavelength light for 4 weeks and in the illumination of mixed light for another 2 weeks. The other animals were raised in the illumination of mixed light or normal light for 6 weeks. All the animals had measurements of refractive status and biometric parameters before and 2, 4, and 6 weeks after being raised in the illumination. Guinea pigs raised in long-wavelength light illumination developed a significant myopia, compared with those raised in mixed-light illumination after 4 weeks. Two weeks of recovery eliminated the refractive differences between the long-wavelength group and the mixed-light group. Compared with the guinea pigs raised in normal conditions, the guinea pigs raised in long-wavelength and mixed lights were more myopic and also showed longer vitreous chamber depth at 2, 4, and 6 weeks. These data suggest that illumination with monochromatic long-wavelength light may lead to myopia and to an abnormal visual experience in newborn pigmented guinea pigs.
authors.affiliation: Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Peking, China. longqinbj@hotmail.com
authors.forename: Qin
authors.initials: Q
authors.lastname: Long
authors.forename: Donghong
authors.initials: D
authors.lastname: Chen
authors.forename: Renyuan
authors.initials: R
authors.lastname: Chu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D005123:Eye / Q000000981:diagnostic imaging / Q000254:growth & development / Q000528:radiation effects*; D006168:Guinea Pigs; D008027:Light / Q000009:adverse effects*; D009216:Myopia / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D010775:Photic Stimulation / Q000009:adverse effects*; D020127:Recovery of Function; D012029:Refraction, Ocular / Q000528:radiation effects*; D042262:Retinoscopy; D012880:Skin Pigmentation; D013997:Time Factors; D014463:Ultrasonography