Myotonic Dystrophy
- Autosomal dominant muscular disorder
- Based on abnormal repetition of DNA trinucleotide segments
- Causes muscle weakness and wasting in arms, legs, neck, face
- Chief concern: life-threatening cardiac conduction defects
- Most common ophthalmic manifestations: cataract, pigmentary retinopathy, ptosis, eye movement deficits
- Many systemic conditions cause cataract, but Christmas tree branching is distinctive
- Pigmentary retinopathy occurs in many systemic conditions
- Ptosis and reduced eye movements occur in many neurologic diseases
- Refer patients suspected of having myotonic dystrophy to ophthalmologists because cataract, ptosis, or retinopathy may impair vision
- Ophthalmic manifestations helpful in diagnosis and sometimes require intervention
