Related Experiment Video
Updated: Feb 7, 2026
05:56
Scleral Cross-linking Using Riboflavin and Ultraviolet-A Radiation for Prevention of Axial Myopia in a Rabbit Model
Published on: April 3, 2016
9.3K
Increased Axial Length Corresponds to Decreased Retinal Light Dose: A Parsimonious Explanation for Decreasing AMD
Michael G Quigley1,2, Ian Powell3, Walter Wittich4,5
1Centre Hospitalier de l'Université de Montréal, University of Montreal, Montreal, Quebec, Canada.
Investigative Ophthalmology & Visual Science
|August 4, 2018
Summary
Higher sunlight exposure increases AMD risk, while myopia may reduce it. This study suggests reduced retinal light dose (RLD) in myopes, potentially explaining their lower AMD risk.
Area of Science:
- Ophthalmology
- Vision Science
- Biomedical Optics
Background:
- Systematic reviews link increased sunlight exposure to higher Age-related Macular Degeneration (AMD) risk.
- Studies suggest protective effects of sunglasses and hats, implying reduced retinal light dose (RLD) may lower AMD risk.
- Myopia is associated with a decreased risk of AMD, prompting investigation into underlying mechanisms.
Purpose of the Study:
- To investigate the hypothesis that reduced retinal light dose (RLD) contributes to the lower Age-related Macular Degeneration (AMD) risk observed in myopic individuals.
- To quantify the relationship between ocular biometric parameters and RLD.
- To explore potential protective mechanisms against AMD through light dose modulation.
Main Methods:
- Employed a one-surface schematic eye model and ray-tracing techniques to calculate RLD.
- Utilized ocular biometric data (spectacle power, vertex distance, corneal power, anterior chamber depth, axial length) from 71 eyes in the Reykjavik Eye Study.
- Validated RLD calculations using advanced optical design software and a comprehensive set of biometric variables.
Main Results:
- Retinal light dose (RLD) was found to be inversely proportional to axial length.
- Ray-tracing analysis revealed that a hyperope with a 21-mm axial length receives 1.8 times more photons per square millimeter on the retina compared to a myope with a 27-mm axial length.
- Bland-Altman plots confirmed the equivalence of two distinct methods for calculating RLD.
Conclusions:
- The inverse relationship between RLD and axial length mirrors the association between axial length and AMD risk.
- Wearing sunglasses can reduce RLD to levels comparable to those in highly myopic individuals.
- These findings suggest that the decreased AMD risk in highly myopic individuals may be attributed to their naturally reduced RLD.
More Related Videos
09:44Identification of Critical Conditions for Immunostaining in the Pea Aphid Embryos: Increasing Tissue Permeability and Decreasing Background Staining
Published on: February 2, 2016
10.5K
06:43Increased Recovery Time and Decreased LPS Administration to Study the Vagus Nerve Stimulation Mechanisms in Limited Inflammatory Responses
Published on: March 29, 2017
10.5K
Related Concept Videos
01:27Decreasing Function
299
A decreasing function describes a relationship where the output consistently declines as the input increases. This means that for any two input values, if one is greater than the other, the corresponding output is smaller. Mathematically, a function f is decreasing on an interval I if for every x1 < x2 in I, f (x1) > f (x2). This type of behavior is visually identified on a graph that slopes downward from left to right.The nature of a function can be analyzed by calculating...
299
01:29Decreased Body Temperature
1.1K
A decreased body temperature can occur in patients with hypothermia and frostbite. Heat loss with extended cold exposure overpowers the body's ability to create heat, resulting in hypothermia. Core temperature readings help classify hypothermia. Mild hypothermia is temperatures between 32 °C (89.6 °F) and 35°C (95 °F) and is caused by impaired thermoregulation. Moderate hypothermia is temperatures between 28 C (82.4 °F) and 32 °C (89.6 °F) caused by...
1.1K
01:14Decreased pulse rate
906
Bradycardia is a medical condition in which the heart rate is slower than normal. It occurs when the heart's natural pacemaker, the sinus node, generates slower electrical impulses than the standard rhythm. In adults, bradycardia is diagnosed when the pulse rate falls below 60 beats per minute, indicating a deviation from the normal heart rate range.
There are specific risk factors that can elevate the likelihood of developing bradycardia. Advanced age is a significant factor, with...
There are specific risk factors that can elevate the likelihood of developing bradycardia. Advanced age is a significant factor, with...
906
01:17Correspondence Bias
229
Correspondence bias, also referred to as the fundamental attribution error, describes the tendency to attribute another person’s behavior to internal characteristics rather than situational influences. This cognitive bias leads individuals to overlook external factors that may be influencing actions, thereby fostering potentially inaccurate assessments of others’ intentions and dispositions.Empirical Evidence for Correspondence BiasResearch has consistently demonstrated the...
229
01:18Axial and Appendicular Muscles
2.8K
Skeletal muscles, the key players in our body's movement, can be classified into two groups based on their location and function: axial muscles and appendicular muscles. These classifications reflect the primary roles the muscles play in the body's structure and movement.
Axial Muscles
Axial muscles, situated along the body's midline, are intricately connected to the axial skeleton, which includes the skull, spine, ribs, and sternum. These muscles facilitate facial expressions and...
Axial Muscles
Axial muscles, situated along the body's midline, are intricately connected to the axial skeleton, which includes the skull, spine, ribs, and sternum. These muscles facilitate facial expressions and...
2.8K
01:09Overview of the Axial Skeleton
9.4K
The skeleton is subdivided into two major divisions—the axial skeleton and the appendicular skeleton. The axial skeleton forms the vertical, central axis of the body. It includes all of the bones of the head, neck, chest, and back. It protects the brain, spinal cord, heart, and lungs. It also serves as the attachment site for muscles that move the head, neck, and back and for muscles that act across the shoulder and hip joints to move their corresponding limbs.
The axial skeleton of the...
The axial skeleton of the...
9.4K