Ocular myopathy

Musculoskeletal Myopathy Growth failure Osteopenia Ocular... 

Large mtDNA deletions account for most cases of ocular myopathy and Pearson s marrow/pancreas syndrome. Ocular myopathy patients can exhibit a variety of clinical symptoms, from mild chronic progressive external ophthalmoplegia (CPEO) to Kearns-Sayre Syndrome (KSS). These diseases are characterized by an early onset of ophthalmoplegia, atypical retinitis pigmentosa, mitochondrial myopathy, and usually cerebellar syndrome and cardiac conduction abnormalities. More than 120 different mtDNA deletions have been identified from patients tissues. Partial duplications of mtDNA have been detected in ocular myopathy and Pearson s syndrome, however, duplications are much rarer than spontaneous deletions in patients with these conditions. Exactly how partial mtDNA duplications arise is unknown. 

The authors performed a Pubmed search over the period 1970—2006. The following keywords were included hypothyroidism, iodine, ocular, visual, ophthalmoplegia, ptosis, myopathy, and eye. The material selected was based on relevance and originality. Any extra information provided was based on the authors personal files and experience. Only articles in the Enghsh language were represented. 

Erdbrink, W. L. Ocular myopathy associated with retinitis pigmentosa. Arch. Ophthal. 57, 335 (1957). 

Subsequent to the acute cholinergic manifestations of OP toxicity in humans, and approximately 24-96 hours after exposure, the onset of an "intermediate syndrome" which includes ocular effects has been recognised more recently for some OPs (Senanayake and Karalliedde, 1987 Karademir et aL, 1990). The associated clinical signs, which are characteristically different from those seen in OP-induced delayed pol)meuropathy, are paralysis and weakness of proximal limbs, respiratory, neck and cranial muscles, including those innervated by the oculomotor nerve. The occurrence of myopathy in rats exposed to diisopropylfluorophosphate, paraoxon or soman (Wecker et aL, 1978 Vanneste and Lison, 1993) resembled the features of the "intermediate syndrome". The severity and duration of the myopathy in rats appeared directly related to the degree of inhibition of AChE. 

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