Aim: to study peripheral refraction and the shape of the eyeball in children with different clinical refraction.
Material And Methods: Using an original method, peripheral refraction was measured at 10-12 degrees temporally and nasally from the fovea in 56 right eyes with different clinical, or axial, refraction of 20 boys and 36 girls aged 7 to 16 years (11.9±1.17 years on average). The shape of the eyeball was judged of by the ratio of its anterior-posterior axial length (AL) to horizontal diameter (HD).
Results: The incidence and value of peripheral myopic defocus in children appeared to decrease with clinical refraction increasing from high hyperopia to high myopia. This was the first time, mixed peripheral refraction was found in children, occurring more frequently in higher myopia. This mixed peripheral defocus, shown to be a transitional stage between relative peripheral myopia and relative hyperopia, indicates non-uniform stretching of posterior pole tissues in the course of refraction development and myopia progression. As ocular refraction increases from high hyperopia to high myopia, the growth of AL outpaces that of HD.
Conclusion: Obviously, natural peripheral defocus results from changes in size and shape of the eyeball in the course of refraction development.
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http://dx.doi.org/10.17116/oftalma2017133170-74 | DOI Listing |
Graefes Arch Clin Exp Ophthalmol
December 2024
Eye Ear Nose and Throat Hospital, Fudan University, XuHui District, No. 19 BaoQing Road, Shanghai, 200031, China.
Purpose: This study aimed to measure the changes in refraction difference value (RDV) in different parts of the retina before and after implantable collamer lenses (ICL) surgery.
Design: Prospective study.
Methods: This study included 40 eyes of 40 patients who underwent ICL implantation for myopia.
Indian J Ophthalmol
December 2024
Cornea, Cataract and Refractive Surgery Services, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
Intrascleral haptic fixation of intraocular lens (IOL) is an extremely useful technique to provide visual rehabilitation in eyes with inadequate capsular support. It requires exteriorization of haptics along with tucking of haptics in the scleral groove preferably and conventionally in the horizontal meridian. In eyes with large corneal diameter, there is difficulty in tucking enough length of the haptics into the intrascleral groove, carrying the risk of slippage of haptics and decentration of IOL.
View Article and Find Full Text PDFFront Neurosci
December 2024
School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong SAR, China.
Purpose: This study evaluates differences in the visual field performance when wearing the Defocus Incorporated Multiple Segments (DIMS) spectacle lens compared to wearing a conventional single vision (SV) spectacle lens.
Methods: Twenty-one children aged 9-14 years with spherical equivalent refraction (SER) between -1.13D to -4.
Front Med (Lausanne)
December 2024
Department of Biopharmaceutics and Clinical Pharmacy, School of Pharmacy, The University of Jordan, Amman, Jordan.
This study investigated how normal corneal stromal profiles change with age, sex, and corrected intraocular pressure (IOP). A retrospective observational analytical study was conducted in Jordan, employing anterior segment spectral-domain optical coherence tomography AS-OCT, a measured corneal stromal thickness (CST) in 134 eyes across the central 6-mm corneal diameter. People between the ages of 18 and 79 were included, and the mean CST values were linked to age groups, IOP, and cis-gender populations, with the exclusion of certain eye conditions.
View Article and Find Full Text PDFJ Int Med Res
December 2024
Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.
Objective: Peripheral refraction is associated with myopia development. Due to a varying prevalence of myopia across different ethnic groups, the aim of the present study was to investigate the peripheral refraction profile in an Arabic population.
Methods: Adults attending an optometry clinic were recruited into this cross-sectional study.
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