Orthokeratology(OK)is a clinical technique that uses reverse geometry design rigid contact lenses to reshape the corneal profile and modify its refractive power during overnight lens wear in order to correct refractiv...Orthokeratology(OK)is a clinical technique that uses reverse geometry design rigid contact lenses to reshape the corneal profile and modify its refractive power during overnight lens wear in order to correct refractive error temporarily.OK achieves its reshaping effect through thinning of the central corneal epithelium.This raises concerns about the safety of this modality particularly in terms of microbial keratitis(MK).Since the mid 2000’s,with our increasing understanding of modifiable risk factors for MK in OK the prevalence of MK appears to have reduced significantly.It is now clear that the relative risk of MK in overnight OK is equivalent to other modalities of contact lens wear,provided that safe practice is followed in terms of lens fitting,wear and care.Although OK was originally used predominantly for correction of low to moderate myopic refractive error,its use for myopia control have become more common in recent years.This follows on from published clinical trials demonstrating an average of approximately 45%reduction in axial eye elongation when overnight OK is used in progressive myopic children.But there is significant individual variability in efficacy,and one of the current challenges for OK in myopia control is to identify those children who will benefit most from this particular intervention.Modifying OK lens parameters to customise corneal reshaping for enhanced myopia control efficacy also remains a significant challenge for the future of this modality.展开更多
Purpose:.To observe the efficacy of toric design orthokeratology.(ortho-k).for correcting myopia and astigmatism in myopic adolescents with moderate to high astigmatism.Methods:.This was a self-controlled clinical stu...Purpose:.To observe the efficacy of toric design orthokeratology.(ortho-k).for correcting myopia and astigmatism in myopic adolescents with moderate to high astigmatism.Methods:.This was a self-controlled clinical study..Twentyfour subjects(42 eyes).aged 9 to 16 years with myopia of 2.50-6.00 D complicated with rule astigmatism of 1.50-3.50 D were fitted with Lucid Night Toric Ortho-k Lenses(LUCID,KOREA)..The changes in uncorrected visual acuity(UCVA),spherical degree, refraction, axial length(AL),.and corneal status were assessed at baseline, 1 night, 1 week, 1 month, 3months, 6 months, and 1 year after the commencement of ortho-k lens wear.Results: The success rate of the first lens fit was 92.8%. The UCVA after ortho-k wearing was improved significantly compared to the baseline during each visit(all P<0.01), and became stable 1 month after ortho-k. The manifest myopia was significantly reduced from(-3.41±1.27) D to(-0.41±0.37) D by toric ortho-k and the degree of astigmatism from(-1.81±0.53)D to(-0.41±0.39) D after 1 month of lens wear(P<0.01).The mean AL was(24.47 ±0.91) mm at baseline, which did not significantly differ from(24.49 ±0.87) mm and(24.48 ±0.94) mm after 6 months and l year,.respectively,.of lens wear(both P >0.05)..Grade 1 corneal staining was observed at 1week(23.8%),.1 month(21.4%), and 1 year(16.7%) following lens wear, and was improved by lens cleaning,.discontinuing lens wear, and moistening the cornea with eye drops.No severe adverse events were reported.Conclusion: The toric ortho-k lens was effective and safe for correction of low to moderate myopia in children with moderate to high astigmatism..The lens also effectively controlled axial length elongation during 1 year of observation..However,the long-term efficacy remains to be elucidated.展开更多
Purpose: The purpose of this study was to evaluate the change in corneal wavefront aberrations in young adults who have been fit with multifocal soft contact lenses for myopia progression control. Findings have been a...Purpose: The purpose of this study was to evaluate the change in corneal wavefront aberrations in young adults who have been fit with multifocal soft contact lenses for myopia progression control. Findings have been analyzed for statistical significance and clinical relevance and compared to reportedly successful Orthokeratology outcomes. Methods: The dominant eye of 40 participants (27 women, 13 men;mean age 27.3 ± 3.2 years;range 23 to 39 years) was fit with Proclear Multifocal center distance lenses (Coopervision, Pleasanton, USA) having a variety of distance powers and reading additions. Refractive errors were limited to a range of –6.00 D up to +1.00 D of sphere, and no greater than –1.00 D of cylinder. Corneal wavefront measurements were performed over 6 mm diameters with a Zeiss Atlas 9000 corneal topographer (Zeiss Meditec, Dublin, USA) prior to, and following lens fitting. Data were converted into rectangular Fourier optics terms M, J0, J45 and RMS values for each reading addition were statistically analyzed. Following evaluation of statistical significance and clinical relevance, results were compared to published data from successful Orthokeratology treatments. Results: Statistically significant changes in higher order aberrations were detected for lenses of all reading additions. Lens groups with higher Add-powers demonstrated stronger changes with increased significance. Final RMS values relating to 2nd, 3rd and 4th Zernike Orders reached clinical significance with a wavefront error of 0.10 μm, the equivalent of 0.25D. Moreover, as Add-powers increased, 3rd and 4th order aberrations likewise showed an increase. Pre-fitting astigmatism values accounted for the highest recorded aberrations and remained predominantly unchanged. Conclusion: Proclear Multifocal center-distance contact lenses were found to increase higher order wavefront aberrations in a manner dependent on their Add-power. In comparison to successful Orthokeratology outcomes, the amounts of resulting aberrations are notably different.展开更多
AIM： To investigate choroidal thickness changes in the horizontal meridian after orthokeratology. METHODS： This is a prospective cross-sectional observed study. Subjects （n=30; 11.3±1.7y） with low-to-moderate...AIM： To investigate choroidal thickness changes in the horizontal meridian after orthokeratology. METHODS： This is a prospective cross-sectional observed study. Subjects （n=30; 11.3±1.7y） with low-to-moderate myopia （-1.0 to -6.0 diopters）, wore orthokeratology （Ortho-K） lenses for 3mo. Before and after Ortho-K, OCT scans were made through the fovea in the horizontal meridian. Choroid thickness around the fovea was acquired by custom software. The analyzed regions along the horizontal meridian were divided into 7 equal zones. Ocular parameters were measured by Lenstar LS 900 non-contact biometry. RESULTS： Only the right eye ocular parameters were analyzed in this study. Before Ortho-K, choroidal thickness along the horizontal meridian was 273.7±31.8 μm in the temporal zone, 253.1±38.6 μm in the macula zone, and 194.8±52.2 μm in the nasal zone. After Ortho-K, the choroid was thicker in each horizontal zone （P〈0.05）. The increased thickness was greatest in the temporal zone （13.5±22.5 μm） and least in the nasal zone （8.4±14.2 μm）. The axial length （AL） increased 0.02 mm （P〉0.05）. The choroid thickness change in each horizontal zone was negatively correlated with AL （r, -0.3 to -0.4; P〈0.05） except one of the nasal zones. CONCLUSION： In myopic children, the thickness of the choroid is greatest in the temporal zone and thinnest in the nasal zone. After nightly Ortho-K for 3mo, the thickness increase along the horizontal meridian. The choroid thickness changes are negatively correlated with the change of AL.展开更多
文摘Orthokeratology(OK)is a clinical technique that uses reverse geometry design rigid contact lenses to reshape the corneal profile and modify its refractive power during overnight lens wear in order to correct refractive error temporarily.OK achieves its reshaping effect through thinning of the central corneal epithelium.This raises concerns about the safety of this modality particularly in terms of microbial keratitis(MK).Since the mid 2000’s,with our increasing understanding of modifiable risk factors for MK in OK the prevalence of MK appears to have reduced significantly.It is now clear that the relative risk of MK in overnight OK is equivalent to other modalities of contact lens wear,provided that safe practice is followed in terms of lens fitting,wear and care.Although OK was originally used predominantly for correction of low to moderate myopic refractive error,its use for myopia control have become more common in recent years.This follows on from published clinical trials demonstrating an average of approximately 45%reduction in axial eye elongation when overnight OK is used in progressive myopic children.But there is significant individual variability in efficacy,and one of the current challenges for OK in myopia control is to identify those children who will benefit most from this particular intervention.Modifying OK lens parameters to customise corneal reshaping for enhanced myopia control efficacy also remains a significant challenge for the future of this modality.
文摘Purpose:.To observe the efficacy of toric design orthokeratology.(ortho-k).for correcting myopia and astigmatism in myopic adolescents with moderate to high astigmatism.Methods:.This was a self-controlled clinical study..Twentyfour subjects(42 eyes).aged 9 to 16 years with myopia of 2.50-6.00 D complicated with rule astigmatism of 1.50-3.50 D were fitted with Lucid Night Toric Ortho-k Lenses(LUCID,KOREA)..The changes in uncorrected visual acuity(UCVA),spherical degree, refraction, axial length(AL),.and corneal status were assessed at baseline, 1 night, 1 week, 1 month, 3months, 6 months, and 1 year after the commencement of ortho-k lens wear.Results: The success rate of the first lens fit was 92.8%. The UCVA after ortho-k wearing was improved significantly compared to the baseline during each visit(all P<0.01), and became stable 1 month after ortho-k. The manifest myopia was significantly reduced from(-3.41±1.27) D to(-0.41±0.37) D by toric ortho-k and the degree of astigmatism from(-1.81±0.53)D to(-0.41±0.39) D after 1 month of lens wear(P<0.01).The mean AL was(24.47 ±0.91) mm at baseline, which did not significantly differ from(24.49 ±0.87) mm and(24.48 ±0.94) mm after 6 months and l year,.respectively,.of lens wear(both P >0.05)..Grade 1 corneal staining was observed at 1week(23.8%),.1 month(21.4%), and 1 year(16.7%) following lens wear, and was improved by lens cleaning,.discontinuing lens wear, and moistening the cornea with eye drops.No severe adverse events were reported.Conclusion: The toric ortho-k lens was effective and safe for correction of low to moderate myopia in children with moderate to high astigmatism..The lens also effectively controlled axial length elongation during 1 year of observation..However,the long-term efficacy remains to be elucidated.
文摘Purpose: The purpose of this study was to evaluate the change in corneal wavefront aberrations in young adults who have been fit with multifocal soft contact lenses for myopia progression control. Findings have been analyzed for statistical significance and clinical relevance and compared to reportedly successful Orthokeratology outcomes. Methods: The dominant eye of 40 participants (27 women, 13 men;mean age 27.3 ± 3.2 years;range 23 to 39 years) was fit with Proclear Multifocal center distance lenses (Coopervision, Pleasanton, USA) having a variety of distance powers and reading additions. Refractive errors were limited to a range of –6.00 D up to +1.00 D of sphere, and no greater than –1.00 D of cylinder. Corneal wavefront measurements were performed over 6 mm diameters with a Zeiss Atlas 9000 corneal topographer (Zeiss Meditec, Dublin, USA) prior to, and following lens fitting. Data were converted into rectangular Fourier optics terms M, J0, J45 and RMS values for each reading addition were statistically analyzed. Following evaluation of statistical significance and clinical relevance, results were compared to published data from successful Orthokeratology treatments. Results: Statistically significant changes in higher order aberrations were detected for lenses of all reading additions. Lens groups with higher Add-powers demonstrated stronger changes with increased significance. Final RMS values relating to 2nd, 3rd and 4th Zernike Orders reached clinical significance with a wavefront error of 0.10 μm, the equivalent of 0.25D. Moreover, as Add-powers increased, 3rd and 4th order aberrations likewise showed an increase. Pre-fitting astigmatism values accounted for the highest recorded aberrations and remained predominantly unchanged. Conclusion: Proclear Multifocal center-distance contact lenses were found to increase higher order wavefront aberrations in a manner dependent on their Add-power. In comparison to successful Orthokeratology outcomes, the amounts of resulting aberrations are notably different.
基金Supported by National Health and Family Planning Commission of the People’s Republic of China(No.201302015)Zhejiang Provincial Natural Science Foundation of China(No.LY14H120007)+1 种基金Wenzhou Commonweal Technology Project(No.Y20150253)Eye Hospital of Wenzhou Medical University Innovation Grant(No.YNCX201402)
文摘AIM： To investigate choroidal thickness changes in the horizontal meridian after orthokeratology. METHODS： This is a prospective cross-sectional observed study. Subjects （n=30; 11.3±1.7y） with low-to-moderate myopia （-1.0 to -6.0 diopters）, wore orthokeratology （Ortho-K） lenses for 3mo. Before and after Ortho-K, OCT scans were made through the fovea in the horizontal meridian. Choroid thickness around the fovea was acquired by custom software. The analyzed regions along the horizontal meridian were divided into 7 equal zones. Ocular parameters were measured by Lenstar LS 900 non-contact biometry. RESULTS： Only the right eye ocular parameters were analyzed in this study. Before Ortho-K, choroidal thickness along the horizontal meridian was 273.7±31.8 μm in the temporal zone, 253.1±38.6 μm in the macula zone, and 194.8±52.2 μm in the nasal zone. After Ortho-K, the choroid was thicker in each horizontal zone （P〈0.05）. The increased thickness was greatest in the temporal zone （13.5±22.5 μm） and least in the nasal zone （8.4±14.2 μm）. The axial length （AL） increased 0.02 mm （P〉0.05）. The choroid thickness change in each horizontal zone was negatively correlated with AL （r, -0.3 to -0.4; P〈0.05） except one of the nasal zones. CONCLUSION： In myopic children, the thickness of the choroid is greatest in the temporal zone and thinnest in the nasal zone. After nightly Ortho-K for 3mo, the thickness increase along the horizontal meridian. The choroid thickness changes are negatively correlated with the change of AL.
