Accommodation Palsy

 Accommodation Palsy

Definition

Failure of accommodation due to palsy of the ciliary muscle.

Etiology: 

This rare disorder is primarily to one of the following causes:

❖Iatrogenic drug-induced palsy due to parasympatholytic agents such asatropine, cyclopentolate scopolamine, homatropine, and tropicamide.

❖ Peripheral causes: Oculomotor palsy, lesions of the ciliary ganglion, or theciliary muscle.

❖ Systemic causes: Damage to the accommodation center in diphtheria, dia-betes mellitus, chronic alcoholism, meningitis, cerebral stroke, multiple sclerosis, syphilis, lead or ergotamine poisoning, medications such as isoniazid or piperazine, and tumors.

Symptoms: 

The failure of accommodation leads to blurred near vision andmay be associated with mydriasis where the sphincter pupillae muscle is also involved. The clinical syndromes listed below exhibit a specific constellation of clinical symptoms and therefore warrant further discussion.

❖ Post-diphtheria accommodation palsy: This transitory palsy is a toxicreaction and occurs without pupillary dysfunction approximately four weeks after infection. Sometimes it is associated with palsy of the soft pal-ate and/or impaired motor function in the lower extremities.

❖ Accommodation palsy in botulism: This is also a toxic palsy. Itdoesinvolve the pupil, producing mydriasis, and can be the first symptom of botulism. It is associated with speech, swallowing, and ocular muscle dys-function accompanied by double vision.

❖ Tonic pupillary contraction is associated with tonic accommodation.

❖ Sympathetic ophthalmia is characterized by a decrease in the range ofaccommodation, even in the unaffected eye.

Measurement of the range of accommodation is indicated whenever sympathetic ophthalmia is suspected.

Diagnostic considerations: 

In addition to measuring the range of accommo-dation with an accommodometer, the examiner should inquire about other ocular and general symptoms.

Treatment: 

This depends on the underlying disorder.

Prognosis: 

The clinical course of tonic pupillary contractionis chronic andresults in irreversible loss of accommodation. The toxic accommodation pal-sies are reversible once the underlying disorder is controlled.

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