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What is A 26 yrs old male with restriction of eye movements in all directions &moderate ptosis but with no diplopia or squint. Diagnosis is - and explain in detail?
Chronic progressive externalophthalmoplegia (CPEO), is a type of eye disorder characterized by slowly progressive inability to move the eyes and eyebrows. It is often the only feature of mitochondrial disease, in which case the term CPEO may be given as the diagnosis.