Purpose: To compare the modulation transfer function and the retinal magnification after myopic correction by replacement of spectacles, laser in situ keratomileusis (LASIK), or phakic intraocular lens (phakic IOL) implantation.
Materials And Methods: Using the ray tracing method, we measured the modulation transfer function and the retinal magnification after these myopic corrections in a Gullstrand eye model.
Results: The modulation transfer function (3-mm pupil, 100 cycles/mm) after phakic IOL implantation for the correction of low, moderate, and high myopia was 45%, 44%, and 44%, respectively. These same measurements after LASIK were 50%, 47%, and 46%, respectively, and the same measurements after spectacle correction were 41%, 32%, and 21%, respectively. The retinal magnification was least changed by the amount of myopic correction after phakic IOL implantation, more changed by LASIK, and most changed by spectacle correction. Specifically, the improvement in the retinal magnification after phakic IOL implantation, LASIK, and spectacle correction for the correction of high myopia was 1.00, 0.97, and 0.88 times, respectively.
Conclusions: There were no significant differences in the modulation transfer function after phakic IOL implantation and LASIK. On the other hand, the modulation transfer function was significantly decreased after spectacle correction, especially when the amount of myopic correction was large. The retinal magnification was least affected by phakic IOL implantation, more affected by LASIK, and most affected by spectacle correction. Phakic IOL implantation and LASIK are considered to be optically excellent correction methods.
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Clin Ophthalmol
December 2024
Department of Refractive Surgery, Eye Clinic Sistina Oftalmologija, Skopje, 1000 Republic of North Macedonia.
Purpose: To explore the significance of changes in anterior chamber depth (ΔACD) and astigmatism between 4 and 8 weeks following uneventful phacoemulsification.
Patients And Methods: Anterior chamber depth (ACD, mm), autorefractometry and subjective refraction were monitored in pseudophakic eyes implanted with non-toric IOLs (group 1, SA60AT, n=36; group 2, SN60WF, n=34; group 3, ICBOO, n=16) and phakic control group (n=30, group 4a, for ACD and autorefractometry) over four weeks. Changes in subjective refractions were compared with repeatability in normal phakic eyes (n=30, group 4b).
Biomed Opt Express
December 2024
Johnson & Johnson MedTech, Van Swietenlaan 5, 9728NX Groningen, The Netherlands.
A new system and methodology are introduced to evaluate photic phenomena induced by different intraocular lens (IOL) technologies using a "see-through" IOL analyzer system in phakic subjects. Nineteen phakic subjects looked through the Groningen IOL Telescope type 1 (GIT1) system under different conditions. Four different IOL designs with different clinical levels of photic phenomena were evaluated by the subjects.
View Article and Find Full Text PDFBiomed Opt Express
December 2024
Laboratorio de Óptica, Universidad de Murcia, Campus de Espinardo, 30100 Murcia, Spain.
Intraocular lenses (IOLs) are routinely used to replace cataractous crystalline lenses. Most current models have a biconvex design that reduces optical quality in the periphery since they are optimized only for central vision. Inverted meniscus IOLs are optimized to achieve similar optical performance to phakic eyes in the peripheral retina.
View Article and Find Full Text PDFBMJ Case Rep
December 2024
Ophthalmology, Hospital CUF Descobertas, Lisboa, Portugal.
Extreme myopic laser-assisted in situ keratomileusis (LASIK) poses challenges regarding future intraocular lens (IOL) power selection. A male patient in his 40s complained of progressive right eye (OD) diminished visual acuity. He had a history of myopic LASIK in both eyes (OU) 20 years before, and implantable collamer lens (ICL) implant in OU 8 years before.
View Article and Find Full Text PDFEur J Ophthalmol
December 2024
Kenezy Hospital Department of Ophthalmology, University of Debrecen, Debrecen, Hungary.
Purpose: To investigate whether diurnal changes in biometric parameters at different times of the day are visible and to analyze whether the variations could have clinical significance in the process of intraocular lens (IOL) power calculation.
Methods: Phakic eyes measured by IOLMaster 700 above the age of 16 were included, with the exclusion of previous surgery. Measurements were taken between 7:00 and 15:00 and data were treated in hourly groups within this range.
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