Asthenopia is becoming a public health problem due to lifestyle changes and increasing usage of computers in colleges and various industries [1] [2]. The term asthenopia includes several different clinical manifestations arising secondary to the excessive use of eyesight [3] [4] [5]. The symptoms are found to have a female preponderance with high school students presenting with ocular symptoms more frequently compared to primary school children due to their increasing use of computers [5]. Specific ocular clinical manifestations are photophobia, blurring of vision, eye redness, diplopia, itching of eyes, excessive tearing, dry eyes, and foreign body sensation [3] [6]. Other symptoms include headaches, eye soreness, fatigue, and irritation [3] [4] [5] [6]. Severe symptoms of asthenopia have been reported to accelerate age-related ocular diseases [7], reduce productivity and quality of life [8] [9]. Factors postulated to have a strong association with asthenopia include computer usage, psychosocial status, environment conditions, posture, and diet.

Asthenopia is classified as either internal or external [3].

• Internal or accommodative asthenopia presents with eye strain and pain inside the eyes and is due to ciliary muscle overuse [3] [6]. It can be caused by uncorrected refractive errors, convergence and accommodation insufficiency, or decompensated heterophoria [6] [10].
• External or muscular asthenopia is due to extraocular muscle weakness and presents with dryness and irritation of the eyes. It is associated with nerve palsies, strabismus, glare from lights, flickering stimuli from computer displays, and dry eyes [3].

• Contusion

  We report a 22-year-old female with a history of contusion of bilateral occipital lobes at the age of 1 year. Magnetic resonance imaging confirmed severe lesion in bilateral striate cortices which should have resulted in cortical blindness. [ncbi.nlm.nih.gov]

  […] muscular asthenopia and eccentric ablation. ( 11780199 ) Wu G....Yao Z. 2001 37 An unusual cause of asthenopia: "pseudo-accommodative insufficiency" associated with a high AC:A ratio. ( 11186867 ) Houston C.A....Weir C.R. 2000 38 Bilateral striate cortex contusion [malacards.org]

• Blurred Vision

  Furthermore, significant correlations were found between total nearwork time and blurred vision, and blurred vision and reduced accommodative facility. [ncbi.nlm.nih.gov]

  Asthenopia encompasses all of the disorders and problems that arise in relation to looking at objects up close such as eye discomfort, blurred vision, sporadic double vision, premature tiredness, the inability to maintain a consistently clear image from [eyecos.eu]

  The symptoms of eye strain are varied and might include: Headaches Blurred vision Light sensitivity Red, watery eyes Painful or sore eyes Dry eyes Tired eyes Back and neck aches Muscle spasms Most, if not all, symptoms of eye strain are easily remedied [specsavers.co.uk]

• Headache

  Symptoms include pain in or around the eyes, headache, dimness of vision, dizziness, and slight nausea. as·the·no·pi·a ( as'thĕ-nō'pē-ă ) Subjective symptoms of ocular fatigue, discomfort, lacrimation, and headaches arising from use of the eyes. [medical-dictionary.thefreedictionary.com]

  After watching S3D TV for 20 min, a survey of subjective symptoms was conducted with a questionnaire to evaluate the degree of S3D perception and asthenopic symptoms such as headache, dizziness and ocular fatigue while watching 3D TV. [ncbi.nlm.nih.gov]

  Asthenopia Definition Eyestrain Subjective symptoms of ocular fatigue, discomfort, lacrimation, and headaches arising from the use of eyes. Weakness or tiring of eyes accompanied by pain, headache, and dimness of vision. [eyewiki.aao.org]

  At times, the intensity of the headaches associated with asthenopia can be considerable and may even result in migraines with nausea and vomiting. B) Myopia. [eyecos.eu]

  It is accompanied by Headache and Weak Eye Sight. [herbpathy.com]

Clinical presentation of asthenopia is similar to various other ocular disorders posing clinicians and optometrists with diagnostic challenges [3] [10]. Evaluation of patient's symptoms along with clinical measures helps to diagnose the condition and plan further management. The workup should start with a detailed history to elicit eyestrain at the college or work, refractive errors, use of spectacles or contact lenses, and previous laser surgery to correct refractive errors. An ophthalmological examination is essential to evaluate tear film, corneal opacities, and refraction. Visual acuity test, cycloplegic refraction test, and fundoscopy must be performed in all cases of asthenopia. The cover or patch test helps to confirm the diagnosis of asthenopia and differentiate between the two types of asthenopia. Persistence of symptoms after patching one eye for several hours indicates accommodative stress while relief of symptoms after resting one eye indicates muscular incompetence. Tests to differentiate accommodative insufficiency from ocular myasthenia gravis such as the Tensilon test, acetylcholine receptor antibody titers, and single fiber electromyography (EMG) testing can also be performed.

Laboratory and radiological studies are usually not indicated during the workup.

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