This study examined effects of uncorrected refractive errors (RE) in a short-duration transient visual evoked potential (SD t-VEP) system and investigated their role for objective measurement of RE. Refractive errors were induced by means of trial lenses in 35 emmetropic subjects. A synchronized single-channel EEG was recorded for emmetropia, and each simulated refractive state to generate 21 VEP responses for each subject. P100 amplitude (N75 trough to P100 peak) and latency were identified by an automated post-signal processing algorithm. Induced hypermetropia and myopia correlated strongly with both P100 amplitude and latency. To minimize the effect of baseline shift and waveform fluctuations, a VEP scoring system, based on software-derived P100 latency, amplitude and waveform quality, was used to estimate the RE. Using the VEP scores, a single VEP response had a high sensitivity and specificity for discerning emmetropia, small RE (<2 diopter) within a 2 diopter range and large RE (2-14 diopter) within a 4 diopter range. The VEP scoring system has a potential for objective screening of RE and for a more accurate 3-step objective refraction.
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http://dx.doi.org/10.1007/s10633-011-9289-7 | DOI Listing |
Clin Ophthalmol
December 2024
Department of Ophthalmology, Visual and Anatomical Sciences, Kresge Eye Institute/Wayne State University School of Medicine, Detroit, MI, USA.
Purpose: To evaluate the outcomes of scleral-fixated intraocular lenses (IOLs) implanted using either Yamane technique or Gore-Tex suture fixation, in comparison to intracapsular lens fixation, and to assess the efficacy of various lens formulas in achieving predicted refractive targets.
Patients And Methods: This study included 45 eyes from 44 patients with scleral-fixated IOLs, comprising 37 Yamane eyes and 8 Gore-Tex eyes. Preoperative refractive predictions from various formulae were compared with final postoperative refraction.
Background: The ciliary muscle is known to play a part in presbyopia, but the mechanism has not received a comprehensive review, which this study aims to achieve. We examined relevant articles published from 1975 through 2022 that explored various properties of the muscle and related tissues in humans and rhesus monkeys. These properties include geometry, elasticity, rigidity, and composition, and were studied using a range of imaging technologies, computer models, and surgical methods.
View Article and Find Full Text PDFSci Rep
December 2024
Department of Ophthalmology, Jinshan Hospital of Fudan University, 1508 Longhang Road, Jinshan District, Shanghai, China.
To observe the structural changes of retina and choroid in patients with different degrees of myopia. We recruited 219 subjects with different degrees of myopia for best corrected visual acuity, computer refraction, intraocular pressure, axial length (AL), optical coherence tomography (OCT) imaging, and other examinations. Central macular retinal thickness (CRT), subfoveal choroidal thickness (SFCT), nasal retinal thickness (NRT), temporal retinal thickness (TRT), nasal choroidal thickness (NCT) and temporal choroidal thickness (TCT) were measured by optical coherence tomography.
View Article and Find Full Text PDFOphthalmic Plast Reconstr Surg
December 2024
Hariram Motumal Nasta & Renu Hariram Nasta Ophthalmic Plastic Surgery Services, KAR Campus.
Purpose: To evaluate the growth, management, and outcomes of epibulbar dermolipomas over a 5-year follow-up period.
Methods: This was a retrospective chart review of epibulbar dermolipoma patients with a minimum follow-up of 5 years, which analyzed the changes in size, refractive errors (spherical equivalent), best-corrected visual acuity, histology, and surgical outcomes.
Results: A total of 61 eyes of 53 patients (32 females) with an average presenting age of 4.
Front Med (Lausanne)
December 2024
Research Unit Vision, Visual Impairments and Blindness, Department of Rehabilitation Sciences, TU Dortmund University, Dortmund, Germany.
Introduction: The increasing prevalence of myopia worldwide is problematic because myopia can result in severe secondary pathologies, and is associated with considerable financial burden. With plenty of prevalence data available for some regions, current data for Europe remain sparse. Yet, information on myopia prevalence and associations is essential for monitoring, preventive and interventive purposes.
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