Eye strain, also medically termed as asthenopia (), is a common

eye An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system. In higher organisms, the ey ...

condition characterized by

non-specific symptom Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature ...

s such as

fatigue Fatigue is a state of tiredness (which is not sleepiness), exhaustion or loss of energy. It is a signs and symptoms, symptom of any of various diseases; it is not a disease in itself. Fatigue (in the medical sense) is sometimes associated wit ...

, pain in or around the eyes,

blurred vision Blurred vision is an ocular symptom where vision becomes less precise and there is added difficulty to resolve fine details. Temporary blurred vision may involve dry eyes, eye infections, alcohol poisoning, hypoglycemia, or low blood pressur ...

headache A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...

, and occasional

double vision Diplopia is the simultaneous perception of two images of a single object that may be displaced in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often voluntary. However, when occ ...

. These symptoms tend to arise after long-term use of

computers A computer is a machine that can be programmed to automatically carry out sequences of arithmetic or logical operations ('' computation''). Modern digital electronic computers can perform generic sets of operations known as ''programs'', ...

, staring at phone screens, digital devices, reading, or other activities that involve extended visual tasks. Various causes contribute to eye strain, including uncorrected vision problems, digital device usage, environmental factors, and underlying health conditions. When concentrating on a visually intense task, such as continuously focusing on a book or computer monitor, the

ciliary muscles The ciliary muscle is an intrinsic muscle of the eye formed as a ring of smooth muscleSchachar, Ronald A. (2012). "Anatomy and Physiology." (Chapter 4) . in the eye's middle layer, the uvea ( vascular layer). It controls accommodation for viewi ...

and the extraocular muscles are strained, also contributing to the symptoms. These symptoms are broadly classified into external (related to the ocular surface) and internal symptom factors (related to eye muscles). Treatment involves environmental modifications, visual aids, and taking periodic breaks. The experience of eye strain when reading in dim light has given rise to the

common misconception Each entry on this list of common misconceptions is worded as a correction; the misconceptions themselves are implied rather than stated. These entries are concise summaries; the main subject articles can be consulted for more detail. Common mis ...

that such an activity causes permanent eye damage.Rachel C. Vreeman, Aaron E. Carroll, "Medical Myths", ''

The British Medical Journal ''The BMJ'' is a fortnightly peer-reviewed medical journal, published by BMJ Publishing Group Ltd, which in turn is wholly-owned by the British Medical Association (BMA). ''The BMJ'' has editorial freedom from the BMA. It is one of the world' ...

'' (now called ''The BMJ'') 335:1288 (December 20, 2007),

Causes

Asthenopia can result from various factors. These causes can be categorized as ocular issues, digital use patterns, environmental factors, or underlying health conditions, including: * Uncorrected

refractive errors Refractive error is a problem with focus (optics), focusing light accurately on the retina due to the shape of the eye and/or cornea. The most common types of refractive error are myopia, near-sightedness, hyperopia, far-sightedness, astigmatis ...

(

astigmatism Astigmatism is a type of refractive error due to rotational asymmetry in the eye's refractive power. The lens and cornea of an eye without astigmatism are nearly spherical, with only a single radius of curvature, and any refractive errors ...

hyperopia Far-sightedness, also known as long-sightedness, hypermetropia, and hyperopia, is a condition of the eye where distant objects are seen clearly but near objects appear blurred. This blur is due to incoming light being focused behind, instead o ...

anisometropia Anisometropia is a condition in which a person's eyes have substantially differing refractive power. Generally, a difference in power of one diopter (1D) is the threshold for diagnosis of the condition. Patients may have up to 3 diopters of anis ...

, etc.) * Eye movement coordination * Accommodative and

vergence A vergence is the simultaneous movement of both eyes in opposite directions to obtain or maintain single binocular vision. When a creature with binocular vision looks at an object, the eyes must rotate around a vertical axis so that the proj ...

stress *

Glare Glare may refer to: * Glare (vision), difficulty seeing in the presence of very bright light * Glaring, a facial expression of squinted eyes and look of contempt * A call collision in telecommunications * GLARE, Glass reinforced aluminium, an ...

* Flickering lights *

Allergy Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include Allergic rhinitis, hay fever, Food allergy, food al ...

* Close viewing distance * Dry-eye *

Fatigue Fatigue is a state of tiredness (which is not sleepiness), exhaustion or loss of energy. It is a signs and symptoms, symptom of any of various diseases; it is not a disease in itself. Fatigue (in the medical sense) is sometimes associated wit ...

* Upward gaze * Prolonged reading from smartphone

Symptoms

Eye strain's symptoms can be broken into two groups: Internal Symptom Factors (ISF) and External Symptom Factors (ESF). ESFs consist of symptoms related to dry-eye such as burning and irritation, seemingly linked to the ocular surface. ISFs are related to pain and ache sensations behind the eye and are linked to accommodative and vergence stress, caused by poor visual conditions. Symptoms of eye strain can include: *

* headache * sore, irritated, burning, or

itching An itch (also known as pruritus) is a sensation that causes a strong desire or reflex to scratch. Itches have resisted many attempts to be classified as any one type of sensory experience. Itches have many similarities to pain, and while both ...

eyes *

dry eyes Dry eye syndrome, also known as keratoconjunctivitis sicca, is the condition of having dry eyes. Symptoms include dryness in the eye, irritation, redness, discharge, blurred vision, and easily fatigued eyes. Symptoms range from mild and occa ...

or watery eyes * eye discomfort * difficulty concentrating * sensitivity to bright lights

Therapy

Given that asthenopia is caused by different factors, treatment may involve the work environment or visual conditions. One known method of relieving strain of the

ocular muscles The extraocular muscles, or extrinsic ocular muscles, are the seven extrinsic muscles of the eye in humans and other animals. Six of the extraocular muscles, the four recti muscles, and the superior and inferior oblique muscles, control movement ...

is taking periodic breaks by closing the eyes and blinking frequently. Often found in connection to Digital Eye Strain (DES), eye strain can be reduced by following the 20-20-20 rule, which consists of looking at something 20 feet away for 20 seconds every 20 minutes.

References

{{Authority control Visual disturbances and blindness Dislocations, sprains and strains Eye injury

Causes

Symptoms

Therapy

See also

References