Spasm of accommodation Causes:- Continuous sever near work in presence of refractive error. Miotic such as pilocarpine eye drop may bring spasm of CM. Precipitating factors:- Marked degree of muscular imbalance (Phoria or Tropia). Trigeminal neuralgia. Dental lesion. Cases of iridocyclitis. The ciliary spasm usually out of the patient’s control (involuntary) and its amount may reach 10Ds or more that leads to marked artificial myopia. Symptoms:- A blurring of near and distant vision. The patient is neurotic and drowzy. All symptoms of accommodative strain in excess. In some patients pilocarpine drop that used in treatment of glaucoma may produce ciliary spasm.

Tropia

Parts of trigeminal nerve

Iridocyclitis

Insufficiency of accommodation In this calculation the accommodation power is constantly below the lower limit of what may be accepted as the normal variation of patient’s age. It’s a relatively common condition may be caused by one of factors:- The failure of accommodation may be lenticular in origin arising from sclerosis of the lens, which is common in presbyopia and affects the physical accommodation only. Weakness of the ciliary muscle leads to failure of physiological accommodation as in physical or mental debility. The etiology of such case includes all the causes of muscle fatigue like: Debility, Anaemia, Malnutrition. Excessive near work in unfavourable conditions. Failure of ciliary muscle may also occur in prodromal stage of chronic simple glaucoma.

Symptoms of insufficiency of accommodation Headaches, asthenopia, eye pain, drowsiness. Near work is blurred and becomes difficult or impossible. Some time, an attempt to read clearly may lead to excessive convergence.

Paralysis of accommodation Causes: General: Drugs like:- Antihypertensive drugs. Antidepressant drugs. Antispasmodic drugs. 2. Any disease or trauma that affects the mid brain or the course of parasympathetic nerve supply to ciliary muscle. 3. Central neurological causes 4. Infectious diseases 5. Non infectious diseases b. Local causes: Short acting cycloplegic drops cyclopentolate. Long acting cycloplegic drops atropine. Eye trauma affecting the ciliary body.

Symptoms and signs of paralysis of accommodation Receding of near point so as the far point and near point becomes close together. Impossible near work. Distance vision is not affected. Full dilation of the pupil, if the sphincter pupillae is affected leads to marked dazzle. Micropsia which is reverse of macropsia in accommodation spasm.

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