Chronic progressive external ophthalmoplegia

Mitochondrial myopathies in general can cause weakness in muscles of the face and neck.^[1] In our search of the medical literature we were able to find case reports describing this symptom in people with chronic progressive external ophthalmoplegia specifically.

Chronic progressive external ophthalmoplegia (CPEO) can be found in other forms of mitochondrial myopathies. In particular, CPEO is found in a related mitochondrial myopathy called Kearns-Sayre Syndrome. In addition, some people with CPEO have some symptoms of Kearns-Sayre syndrome, such as ataxia, dementia, or sensorineural hearing loss, in addition to the characteristic symptoms of CPEO. In these cases the people may be said to have CPEO-plus.^[2][3]

CPEO may also be found in other disorder such as oculopharyngeal muscular dystrophy, and myasthenia gravis.^[2] 

Ptosis caused by chronic progressive external ophthalmoplegia (CPEO) can be corrected by surgery, or by using glasses that have a “ptosis crutch” to lift the upper eyelids.^[1] Strabismus surgery can be helpful in carefully selected patients if diplopia (double vision) occurs.^[4]

Some individuals with a deficiency of coenzyme Q10 have CPEO as an associated abnormality. Coenzyme Q10 is important for normal mitochondrial function. In individuals with this deficiency, supplemental coenzyme Q10 has been found to improve general neurologic function and exercise tolerance. However, coenzyme Q10 has not been shown to improve the ophthalmoplegia or ptosis in people who have isolated CPEO.^[2]

Chronic progressive external ophthalmoplegia (CPEO) can be an isolated condition, or it can occur as part of other underlying conditions, such as ataxia neuropathy spectrum and Kearns-Sayre syndrome. These conditions may involve not only CPEO, but various additional features that are not shared by most individuals with CPEO in isolation.^[3] Individuals with isolated CPEO generally have a normal life expectancy. While symptoms tend to worsen over time, the specific symptoms and their severity can vary greatly from person to person. Therefore, when symptoms first appear, the course of the condition is very difficult to predict.^[2][5]

For individuals with additional symptoms or another underlying condition associated with CPEO, the prognosis depends on the specific signs and symptoms present and/or the outlook associated with the underlying condition in the affected individual. For this reason, obtaining an accurate diagnosis is very important.