Progressive external ophthalmoplegia
Overview
A slow progressive paralysis of the motor nerves of the eye (external eye muscles). The condition is often abbreviated to PEO. PEO is usually caused by mitochondrial diseases such as mitochondrial myopathy. Muscles are the most frequently affected organs in mitochondrial disease.
Symptoms
* Eye movement weakness * Ptosis * Ocular paresis * Eyelid weakness * Progressive ptosis * Lack of eye mobility * Drooping upper eyelid * Atrophic eyelids * Thin eyelids
Diagnosis
If the patient’s eye pain doesn’t result from a chemical burn or from acute angle-closure glaucoma, take a complete history. Have the patient describe the pain fully. Is it an ache or a sharp pain? How long does it last? Is it accompanied by burning, itching, or a discharge? Find out when it began. Is it worse in the morning or late in the evening? Ask about recent trauma or surgery, especially if the patient complains of severe pain that developed suddenly. Does he have headaches? If so, find out how often and at what time of day they occur. During the physical examination, don’t manipulate the eye if you suspect trauma. Carefully assess the eyelids and conjunctivae for redness, inflammation, and swelling. Then examine the eyes for ptosis or exophthalmos. Finally, test visual acuity with and without correction, and assess extraocular movements. Characterize any discharge.
Treatment
If the patient’s eye pain results from a chemical burn, remove contact lenses (if present) and irrigate the eye with at least 1 L of normal saline solution over 10 minutes. Evert the lids and wipe the fornices with a cotton-tipped applicator to remove any particles or chemicals. Eye pain from acute angle-closure glaucoma is an ocular emergency requiring immediate intervention to decrease intraocular pressure (IOP). If drug treatment doesn’t reduce IOP, the patient will need laser iridotomy or surgical peripheral iridectomy to save his vision.