Related Experiment Video
Updated: Sep 10, 2025
08:28
Development of an In Vitro Ocular Platform to Test Contact Lenses
Published on: April 6, 2016
10.7K
Ocular surface characteristics and its association with soft contact lens fitting
Javier Rojas Viñuela1, James S Wolffsohn2, Alejandra Consejo3
1Natural Optics Balaguer, Lleida, Spain.
Summary
Soft contact lens fit is influenced by the corneoscleral junction, not just sagittal height. Peripheral ocular parameters, especially slopes in superior and inferior quadrants, are key for optimal soft contact lens fitting.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Optometry
Background:
- Soft contact lens fitting is crucial for visual acuity and ocular health.
- Understanding the relationship between ocular surface topography and lens fit is essential for improving lens design and patient outcomes.
Purpose of the Study:
- To analyze the associations between ocular surface shape parameters and soft contact lens fitting.
- To investigate the role of corneo-scleral junction (CSJ) parameters in soft contact lens (SCL) movement.
Main Methods:
- Retrospective analysis of 106 eyes fitted with standard silicone hydrogel soft lenses.
- Objective lens fit analysis using proprietary software and Eye Surface Profiler for corneo-scleral parameters.
- Characterization of delta-sag (δ-sag) as the relationship between ocular (OC-SAG) and lens (CL-SAG) sagittal height.
Main Results:
- No significant correlation found between δ-sag and lens fitting features.
- Statistically significant differences in corneoscleral junction (CSJ) angle and peripheral corneal/scleral slopes between right and left eyes.
- Moderate to strong associations between lens fit and peripheral ocular parameters, though not consistent between eyes.
Conclusions:
- Soft contact lens movement is influenced by the corneoscleral transition, particularly in superior and inferior quadrants.
- Focusing on peripheral slopes is more beneficial for soft contact lens fitting than central corneal parameters or sagittal height.
- Asymmetrical ocular surface topography may impact soft contact lens fit consistency between eyes.
Related Concept Videos
01:16Focusing of Light in the Eye
3.2K
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
3.2K
01:17Accessory Structures of the Eye
1.9K
Optical perception, or vision, is an extraordinary sense dependent on converting light signals received via the ocular organs. These organs, known as eyes, are securely positioned within the bony cavities of the skull, called orbits. The orbits serve a dual purpose: a protective shield for the ocular globes and a stable attachment point for the soft ocular tissues. The eye's external protective mechanisms include the eyelids, which are edged with lashes that act as a barrier against foreign...
1.9K
01:25Glaucoma: Overview
749
Glaucoma is an eye condition characterized by increased intraocular pressure that damages the retina and optic nerve, leading to irreversible blindness if left untreated. The human eye has various components, including the cornea, iris, pupil, lens, and optic nerve. Aqueous humor is secreted by the epithelium of the ciliary body in the posterior chamber and flows through the trabecular meshwork and canal of Schlemm, maintaining normal intraocular pressure. The trabecular meshwork and the canal...
749
01:27Open Angle Glaucoma: Treatment
561
In open-angle glaucoma, the iridocorneal angle remains open, but the trabecular meshwork becomes stiff, slowing down the outflow of aqueous humor. This causes a buildup of aqueous humor in the anterior chamber, leading to a sudden increase in intraocular pressure. The treatment for open-angle glaucoma focuses on reducing the elevated intraocular pressure by either decreasing the secretion of aqueous humor or increasing its outflow.
Drugs such as carbonic anhydrase inhibitors, α2- and...
Drugs such as carbonic anhydrase inhibitors, α2- and...
561
01:28Angle Closure Glaucoma: Treatment
674
Angle-closure glaucoma, or closed-angle glaucoma, is an eye condition where the iris bulges out and blocks the iridocorneal angle, resulting in a buildup of aqueous humor and increased intraocular pressure. Immediate medical attention is necessary due to the sudden onset of symptoms. The treatment for angle-closure glaucoma includes short-term and long-term approaches. Short-term treatment involves using eye drops like pilocarpine to lower intraocular pressure by increasing aqueous humor...
674
01:13Contact Angle
13.2K
When a solid is dipped inside a liquid, the liquid surface becomes curved near the contact. For some solid–liquid interfaces, the liquid is pulled up along the solid, while for others, the liquid surface is convex or depressed near the solid surface. This phenomenon can be explained using the concept of cohesive and adhesive forces.
The adhesive force is the molecular force between molecules of different materials, that is, between the molecules of the solid and the liquid. The cohesive...
The adhesive force is the molecular force between molecules of different materials, that is, between the molecules of the solid and the liquid. The cohesive...
13.2K