- A diagnosis of myotonic dystrophy is made by a physician. A physical examination and a complete history are necessary for a doctor to assess the presence of myotonia, muscle weakness and any decrease in muscle size. Details of a positive family history, if present, will be investigated, as well as the history of the client’s present concerns.
- Diagnostic tests are also used by the physician in making a positive diagnosis of myotonic dystrophy.
- DNA Analysis performed on a sample of blood is a valuablediagnostic tool. This genetic test is used to make the diagnosis of myotonicdystrophy more exact. It identifies the presence or absence of the geneticfault that is responsible for myotonic dystrophy. Where there is a positivefamily history, the use of this test during pregnancy can also determinewhether or not a fetus is affected by myotonic dystrophy.
- An electromyogram (EMG),a test designed to measure and record electrical activity in muscles, is usefulin diagnosing many disorders affecting muscle. Electrodes are attached to thebody in a painless procedure. Accurate descriptions of muscle activity provideevidence of the presence or absence of myotonic dystrophy.
- A muscle biopsy is necessarywhenever a physician wants to clarify the diagnosis. A sample muscle tissue isexamined under a microscope for changes characteristic of myotonic dystrophy.
- An eye examination can identifythe opacities seen in the lens of a person who has cataracts. The presence ofcataracts may be the first or in some cases, the only symptoms seen in a personwith myotonic dystrophy. This information is important for diagnosis as well asfor management.