Amblyopia: Nursing

00:00 / 00:00



Amblyopia is a condition in which there’s reduced vision in one eye due to abnormal visual development. Amblyopia is commonly referred to as lazy eye, because the affected eye is weaker and often wanders inward or outward.

First, let’s quickly review the physiology of vision. Visual development begins during the first days of life, when the newborn starts receiving visual stimuli from the external world. This helps maturation of the visual pathways connecting the eyes and brain, until they reach maturity at about 4 years of age.

Okay, now, the visual pathways begin in the eye. If we zoom into the wall of the eye, there's an outer fibrous layer, which contains the cornea and sclera, and helps control the focus and entry of light. So the light that passes through the cornea is directed to the lens, which in turn collects light arrays and focuses them into the retina at the back of the eye. The retina houses photoreceptors that translate light into electrical impulses, which are then carried by the optic nerve into the visual cortex of the brain. Finally, the visual cortex processes the impulses coming from both eyes, and fuses them into one clear image.

Now, the causes of amblyopia include any condition that interferes with normal visual development, such as strabismus, or an abnormal alignment of the eyes; astigmatism, which is when light doesn’t focus properly on the retina, causing blurry vision; as well as refractive errors, like near- or farsightedness, and differences in visual acuity between the two eyes. Other causes include eye trauma; ptosis, which is drooping of the upper eyelid; congenital cataract, which is clouding of the eye lens; as well as corneal opacities and eyelid hemangioma. These conditions can also be considered risk factors for amblyopia, along with a family history of amblyopia, premature birth, and neurodevelopmental disorders .


Amblyopia, more commonly referred to as "lazy eye", occurs as a result of a failure of cortical visual development in one or both eyes from eye pathology early in life. It typically results in one eye having markedly better vision than the other. This causes the "weaker" eye to become suppressed. Amblyopia is the most common cause of visual impairment in children.


Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Cookies are used by this site.

USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.