Purpose: To quantify on-eye rotational and translational stability of three scleral contact lens stabilization methods and to model the variation in visual acuity when these movements occur in a wavefront-guided correction for highly aberrated eyes.
Methods: Three lens stabilization methods were integrated into the posterior periphery of a scleral contact lens designed at the Visual Optics Institute. For comparison, a lens with no stabilization method (rotationally symmetric posterior periphery) was designed. The lenses were manufactured and lens movements were quantified on 8 eyes as the average SD of the observed translations and rotations over 60 min of wear. In addition, the predicted changes in acuity for five eyes with keratoconus wearing a simulated wavefront-guided correction (full correction through the fifth order) were modeled using the measured movements.
Results: For each lens design, no significant differences in the translation and rotation were found between left and right eyes, and lenses behaved similarly on all subjects. All three designs with peripheral stability modifications exhibited no statistically significant differences in translation and rotation distributions of lens movement and were statistically more stable than the spherical lens in rotation. When the measured movements were used to simulate variation in visual performance, the 3 lenses with integrated stability methods showed a predicted average loss in acuity from the perfectly aligned condition of approximately 0.06 logMAR (3 letters), compared with the loss of over 0.14 logMAR (7 letters) for the lens with the spherical periphery.
Conclusion: All three stabilization methods provided superior stability, as compared with the spherical lens design. Simulations of the optical and visual performance suggest that all three stabilization designs can provide desirable results when used in the delivery of a wavefront-guided correction for a highly aberrated eye.
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http://dx.doi.org/10.1097/ICL.0000000000000145 | DOI Listing |
J Contact Lens Res Sci
July 2024
Illinois College of Optometry, Chicago.
Background And Objective: This study determined whether practitioners specializing in keratoconus (KC) adhere to published guidelines for disease management and to what extent comorbid conditions of dry eye, contact lens tolerance, and psychological consequences of KC are formally assessed as part of long-term management.
Materials And Methods: This cross-sectional study used an IRB-approved, Internet-based, REDCap platform. Descriptive statistics are presented.
Eye Contact Lens
January 2025
Lewis Katz School of Medicine at Temple University (F.A.), Philadelphia, PA; and Wilmer Eye Institute (L.D.M., K.B., A.C.), Baltimore, MD.
Objective: To determine if scleral fittings that occur before corneal cross-linking (CXL) are still successful after the procedure.
Methods: This prospective study included seven patients with keratoconus or post-laser-assisted in situ keratomileusis (LASIK) corneal ectasia who were fitted with scleral lenses then underwent CXL. Four patients (six eyes) had keratoconus and three patients (five eyes) had post-LASIK ectasia.
Eye Contact Lens
January 2025
Department of Ophthalmology, Ege University Faculty of Medicine, Izmir, Turkiye.
Objectives: To evaluate scleral thickness of patients with keratoconus by anterior segment optical coherence tomography (AS-OCT).
Materials And Methods: Fifty-two eyes of 42 patients with keratoconus (group 1) and 42 right eyes of 42 healthy individuals (group 2) were included. Scleral thickness measurements were taken with AS-OCT 6, 4, and 2 mm behind the scleral spur in four gaze positions: superior, inferior, temporal, and nasal.
Ophthalmic Physiol Opt
January 2025
Contact Lens and Visual Optics Laboratory, Optometry and Vision Science, Centre for Vision and Eye Research, Queensland University of Technology, Brisbane, Queensland, Australia.
Introduction: Tear exchange during contact lens wear is essential for ocular surface integrity, facilitating debris removal, and maintaining corneal metabolism. Fluorophotometry and fluorogram methods are typically used to measure tear exchange, which require hardware modifications to a slit lamp biomicroscope. This manuscript introduces an alternative method using a corneoscleral profilometer, the Eye Surface Profiler (ESP), to quantify tear exchange during corneal and scleral rigid lens wear by assessing fluorescence intensity changes over time.
View Article and Find Full Text PDFClin Exp Optom
January 2025
Eurolens Research, Division of Pharmacy and Optometry, The University of Manchester, Manchester, UK.
Clinical Relevance: Knowledge of contact lens prescribing trends can (a) assist practitioners to benchmark their own prescribing habits, (b) help the contact lens industry understand preferred products, and (c) support academics in scholarly writings.
Background: This work aims to document contact lens prescribing trends in Australia over the past quarter of a century.
Methods: An annual survey of contact lens prescribing trends was conducted in Australia each year from 2000 to 2024, inclusive, by asking optometrists to provide information relating to 10 consecutive contact lens fits undertaken between January and March.
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