Solid phase radionuclide esophageal motility in polymyositis and dermatomyositis.

Polymyositis (PM) and dermatomyositis (DM) may be associated with motor dysfunction of the entire gastrointestinal tract. Abnormal esophageal motor function is a well-recognized complication of these diseases. In this study, we used a solid phase esophageal study to evaluate the motor function in patients with PM or DM. Twenty-three patients and 36 age-matched normal volunteers were studied. Each subject was placed in a supine position above a gamma camera linked to a computer and was given a 4-ml bolus of solid gelatin containing 1 mCi of Tc-99m phytate. Data were acquired in the list mode. A computer method modified from Kelim and Wald and Russell et al. was used to calculate the following: A) total mean transit time (MTT); B) residual fraction after the first swallow (RF); and C) retrograde index (RI). All values are presented as mean +/- standard deviation (SD). The Student's t-test was used to test statistical significance. Our preliminary results suggest: 1) delayed esophageal emptying is common (17/23) in PM/DM, indicating frequent malfunction of the smooth muscle of the upper gastrointestinal tract in PM/DM and 2) measurement of esophageal motility may monitor disease activity in PM/DM.