myotonic dystrophy

n.
  1. A chronic, slowly progressing, inherited disease that usually manifests its first symptoms when individuals reach their 30s, characterized by a wasting of the muscles, failing vision, opacity of the lens of the eyes, ptosis, slurred speech, and general muscular weakness.myotonia atrophica Steinert's disease
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.