AIM:To compare the effects of manipulating light levels versus manipulating the spectral content of short wavelengths(blue light)of ambient lighting on refractive development in young rabbits.METHODS:A total of 32 hea...AIM:To compare the effects of manipulating light levels versus manipulating the spectral content of short wavelengths(blue light)of ambient lighting on refractive development in young rabbits.METHODS:A total of 32 healthy 3-week-old rabbits were randomly assigned to one of the four groups with 8 in each group for 12wk:Control group(NC)under low blue light(output ratio of blue light 1.8%)at low illuminance(341 lx),HI group under low blue light(output ratio of blue light 1.6%)at high illuminance(5057 lx),simulating natural light(S-NL)group under high blue light(output ratio of blue light 4.9%)at high illuminance(5052 lx),and MB group under high blue light(output ratio of blue light 5.2%)at low illuminance(342 lx).The lighting in each group were provided by light emitting diode(LED)lamps emitting visible light(range 380-780 nm)in addition to(or not)LED lamps only emitting short wavelength(range 380-500 nm).Refraction,axial length,and corneal curvature radius were assessed by retinoscopy,ultrasonography and keratometry,respectively.Average data of both eyes for each animal were used as single values and compared among groups.RESULTS:During the 12-week intervention,all animals had an emmetropization period.The decrease of refraction in rabbits in HI group was similar to S-NL group,both slower than that of NC group(P<0.001).At the 12th week,the refraction(3.000±0.267 D)and vitreous cavity depth(7.421±0.168 mm)of S-NL was similar to HI group(3.250±0.267 D,7.264±0.256 mm),significantly different from NC group(1.937±0.291 D,7.825±0.313 mm;P<0.001 for both).High blue light at low illuminance had little effect on refraction change.At the end of intervention,the difference of refraction(2.219±0.281 D)and vitreous cavity depth(7.785±0.229 mm)in MB group were not statistically significant(P=0.311,P=0.749)compared with NC group.The other components were less affected by lighting conditions(P>0.05).CONCLUSION:The light levels per se but not the rich in spectral content of short wavelengths determine the inhibitory effect of ambient lighting on myopia development in rabbits.展开更多
AIM:To investigate demographic and preoperative factors increasing the risk of ametropia following transepithelial photorefractive keratectomy(trans PRK)in myopia and myopic astigmatism.METHODS:This retrospective coho...AIM:To investigate demographic and preoperative factors increasing the risk of ametropia following transepithelial photorefractive keratectomy(trans PRK)in myopia and myopic astigmatism.METHODS:This retrospective cohort study included myopic eyes(-0.50 to-8.75 D)with or without astigmatism(up to 3.50 D)enrolled at Dr.Yap Eye Hospital Yogyakarta.Trans PRK was performed using Technolaz 217 z100 excimer laser.Subjects were clustered into ametropia and emmetropia group based on uncorrected distance visual acuities(UDVA)3 mo post-operatively.Multiple preoperative and intraoperative parameters were analyzed using Logistic regression to obtain their effect on ametropia risk following trans PRK.RESULTS:A total of 140 eyes of 87 consecutive subjects were studied.Prevalence of ametropia following trans PRK was 20(14.29%)eyes.Subjects in ametropia group were significantly older than the emmetropia group(31.80±14.23 vs 18.88±2.41,respectively;P<0.001).Bivariate Logistic regression analysis showed that older age(OR=1.23),higher preoperative spherical equivalent(>-6 D;OR=12.78),steeper anterior keratometric readings(Kmax>45 D and mean K>44 D;OR=4.28 and 4.35,respectively)increased the risk of ametropia following trans PRK.Adjusted multivariate Logistic regression analysis showed that age was the strongest predictor for the incidence of ametropia following trans PRK.Complications of trans PRK were overcorrection,suspected posterior keratoectasia and accommodation insuffiency.CONCLUSION:Older age can be the strongest factor for increasing ametropia risk following trans PRK.Cut-off points of Kmax and mean K at 45 and 44 D respectively are proposed as the predictors for ametropia following trans PRK.展开更多
Background Pax-6 gene plays an important role in the process of eye development. This study was to determine the role of pax-6 in the axial myopia produced by hyperopic optical defocus and form deprivation in infant ...Background Pax-6 gene plays an important role in the process of eye development. This study was to determine the role of pax-6 in the axial myopia produced by hyperopic optical defocus and form deprivation in infant monkeys Methods Among seven normal infant rhesus monkeys (aged 1 to 1 5 months), five wore -3 00 D spectacle lenses over their right eyes and zero-powered lenses over their left eyes Monocular form deprivation was produced by eyelid fusion in two monkeys Ten weeks later, the monkeys were sacrificed by an overdose of barbiturates and their eyes were removed immediately A 5 mm×5 mm button of retina and sclera was taken from the posterior poles along with a 4-mm optic nerve RNA was isolated separately from each of these three types of tissues After that, reverse transcription polymerase chain reaction (RT-PCR) was used for determining gene expression in the retina, sclera and optic nerve Semi-quantitative analyses were performed on the PCR products Results As expected, the optically induced hyperopic defocus and the form deprivation produced myopic growth For the lens-treatment monkeys, pax-6 gene expression in the retinas of the defocused eyes was significantly higher than in the retinas of the left eyes ( t =5 703, P =0 005) However, there were no analogous significant differences between pax-6 expression in the scleras or the optic nerves For the two form-deprived monkeys, there were no obvious differences in pax-6 gene expression in the retinas or the optic nerves Conclusion The result that the expression of pax-6 was enhanced by hyperopic defocus in the infant monkey retina suggests that pax-6 may be involved in vision-dependent eye growth and emmetropization展开更多
基金Supported by Natural Science Foundation of Sichuan Province(No.2022NSFSC0754)Project of Nanchong Science and Technology Bureau(No.22SXQT0350).
文摘AIM:To compare the effects of manipulating light levels versus manipulating the spectral content of short wavelengths(blue light)of ambient lighting on refractive development in young rabbits.METHODS:A total of 32 healthy 3-week-old rabbits were randomly assigned to one of the four groups with 8 in each group for 12wk:Control group(NC)under low blue light(output ratio of blue light 1.8%)at low illuminance(341 lx),HI group under low blue light(output ratio of blue light 1.6%)at high illuminance(5057 lx),simulating natural light(S-NL)group under high blue light(output ratio of blue light 4.9%)at high illuminance(5052 lx),and MB group under high blue light(output ratio of blue light 5.2%)at low illuminance(342 lx).The lighting in each group were provided by light emitting diode(LED)lamps emitting visible light(range 380-780 nm)in addition to(or not)LED lamps only emitting short wavelength(range 380-500 nm).Refraction,axial length,and corneal curvature radius were assessed by retinoscopy,ultrasonography and keratometry,respectively.Average data of both eyes for each animal were used as single values and compared among groups.RESULTS:During the 12-week intervention,all animals had an emmetropization period.The decrease of refraction in rabbits in HI group was similar to S-NL group,both slower than that of NC group(P<0.001).At the 12th week,the refraction(3.000±0.267 D)and vitreous cavity depth(7.421±0.168 mm)of S-NL was similar to HI group(3.250±0.267 D,7.264±0.256 mm),significantly different from NC group(1.937±0.291 D,7.825±0.313 mm;P<0.001 for both).High blue light at low illuminance had little effect on refraction change.At the end of intervention,the difference of refraction(2.219±0.281 D)and vitreous cavity depth(7.785±0.229 mm)in MB group were not statistically significant(P=0.311,P=0.749)compared with NC group.The other components were less affected by lighting conditions(P>0.05).CONCLUSION:The light levels per se but not the rich in spectral content of short wavelengths determine the inhibitory effect of ambient lighting on myopia development in rabbits.
文摘AIM:To investigate demographic and preoperative factors increasing the risk of ametropia following transepithelial photorefractive keratectomy(trans PRK)in myopia and myopic astigmatism.METHODS:This retrospective cohort study included myopic eyes(-0.50 to-8.75 D)with or without astigmatism(up to 3.50 D)enrolled at Dr.Yap Eye Hospital Yogyakarta.Trans PRK was performed using Technolaz 217 z100 excimer laser.Subjects were clustered into ametropia and emmetropia group based on uncorrected distance visual acuities(UDVA)3 mo post-operatively.Multiple preoperative and intraoperative parameters were analyzed using Logistic regression to obtain their effect on ametropia risk following trans PRK.RESULTS:A total of 140 eyes of 87 consecutive subjects were studied.Prevalence of ametropia following trans PRK was 20(14.29%)eyes.Subjects in ametropia group were significantly older than the emmetropia group(31.80±14.23 vs 18.88±2.41,respectively;P<0.001).Bivariate Logistic regression analysis showed that older age(OR=1.23),higher preoperative spherical equivalent(>-6 D;OR=12.78),steeper anterior keratometric readings(Kmax>45 D and mean K>44 D;OR=4.28 and 4.35,respectively)increased the risk of ametropia following trans PRK.Adjusted multivariate Logistic regression analysis showed that age was the strongest predictor for the incidence of ametropia following trans PRK.Complications of trans PRK were overcorrection,suspected posterior keratoectasia and accommodation insuffiency.CONCLUSION:Older age can be the strongest factor for increasing ametropia risk following trans PRK.Cut-off points of Kmax and mean K at 45 and 44 D respectively are proposed as the predictors for ametropia following trans PRK.
基金ThestudywassupportedbygrantsfromtheNationalNaturalScienceFoundationofChina (No .3 0 10 0 2 0 5and 3 0 1710 0 1)andfromtheFokYingTungEducationFoundation (No .910 43 )
文摘Background Pax-6 gene plays an important role in the process of eye development. This study was to determine the role of pax-6 in the axial myopia produced by hyperopic optical defocus and form deprivation in infant monkeys Methods Among seven normal infant rhesus monkeys (aged 1 to 1 5 months), five wore -3 00 D spectacle lenses over their right eyes and zero-powered lenses over their left eyes Monocular form deprivation was produced by eyelid fusion in two monkeys Ten weeks later, the monkeys were sacrificed by an overdose of barbiturates and their eyes were removed immediately A 5 mm×5 mm button of retina and sclera was taken from the posterior poles along with a 4-mm optic nerve RNA was isolated separately from each of these three types of tissues After that, reverse transcription polymerase chain reaction (RT-PCR) was used for determining gene expression in the retina, sclera and optic nerve Semi-quantitative analyses were performed on the PCR products Results As expected, the optically induced hyperopic defocus and the form deprivation produced myopic growth For the lens-treatment monkeys, pax-6 gene expression in the retinas of the defocused eyes was significantly higher than in the retinas of the left eyes ( t =5 703, P =0 005) However, there were no analogous significant differences between pax-6 expression in the scleras or the optic nerves For the two form-deprived monkeys, there were no obvious differences in pax-6 gene expression in the retinas or the optic nerves Conclusion The result that the expression of pax-6 was enhanced by hyperopic defocus in the infant monkey retina suggests that pax-6 may be involved in vision-dependent eye growth and emmetropization
