Related Experiment Video
Updated: Mar 15, 2026
05:45
Author Spotlight: In-Depth Morphometric Examination and Quantification of Native Lens Structure Using Whole Mount Imaging
Published on: January 19, 2024
1.6K
The physiological optics of the lens
Paul J Donaldson1, Angus C Grey2, Bianca Maceo Heilman2
1Department of Physiology, School of Medical Sciences, University of Auckland, New Zealand; School of Optometry and Vision Science, University of Auckland, New Zealand.
Progress in Retinal and Eye Research
|September 19, 2016
Summary
The ocular lens maintains vision quality through cellular mechanisms regulating water transport. This process is crucial for lens transparency and focusing power, preventing age-related vision impairments like presbyopia and cataract.
Area of Science:
- Ophthalmology
- Cell Biology
- Biophysics
Background:
- The ocular lens is vital for vision, providing focusing power and correcting corneal aberrations.
- Lens optical properties change with age, leading to presbyopia (refractive error) and cataract (clouding).
- The cellular mechanisms underlying these age-related changes remain poorly understood.
Purpose of the Study:
- To review how lens optical properties are established and maintained at the cellular level throughout life.
- To elucidate the role of the lens microcirculation system in maintaining transparency and refractive properties.
- To highlight water transport as a critical link between lens cellular function and age-related vision decline.
Main Methods:
- Literature review focusing on cellular and molecular mechanisms of lens function.
- Analysis of the lens microcirculation system's role in homeostasis.
- Examination of water transport's impact on lens geometry and refractive index gradients.
Main Results:
- The lens microcirculation system generates ion and water flux, essential for maintaining lens homeostasis.
- This system actively preserves lens transparency and regulates water content.
- Regulated water content controls lens geometry and refractive index gradients, determining focusing power.
Conclusions:
- Water transport is a critical cellular parameter linking lens transparency and refractive properties.
- Age-related alterations in water transport likely initiate presbyopia and cataract.
- Further research into age-related water transport changes is needed to understand and combat major causes of vision loss.
Related Concept Videos
01:16Focusing of Light in the Eye
7.0K
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...
7.0K
01:18Imaging Biological Samples with Optical Microscopy
12.1K
Optical microscopy uses optic principles to provide detailed images of samples. Antonie van Leeuwenhoek designed the first compound optical microscope in the 17th century to visualize blood cells, bacteria, and yeast cells. In 1830, Joseph Jackson Lister created an essentially modern light microscope. The 20th century saw the development of microscopes with enhanced magnification and resolution.
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
12.1K
01:20Anatomy of the Eyeball
11.2K
The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle...
11.2K
01:17Accessory Structures of the Eye
4.2K
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...
4.2K
01:24Vision
61.2K
Vision is the result of light being detected and transduced into neural signals by the retina of the eye. This information is then further analyzed and interpreted by the brain. First, light enters the front of the eye and is focused by the cornea and lens onto the retina—a thin sheet of neural tissue lining the back of the eye. Because of refraction through the convex lens of the eye, images are projected onto the retina upside-down and reversed.
61.2K
01:25Glaucoma: Overview
1.6K
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...
1.6K