Ultrasonography: not useful in detecting susceptibility to malignant hyperthermia.

MH is a rare, potentially fatal complication of general anesthesia. Halothane-caffeine contracture testing of a muscle biopsy is the only accepted diagnostic test for MH. A previous report indicated that ultrasonography may aid in diagnosis of MH. Using sonographic examination of the thigh and calf, we evaluated eight patients with proved susceptibility to MH and eight control patients. Two radiologists independently evaluated the sonograms for echogenicity and definition of fascial planes. We detected no consistent and reliable differences between control and MH patients. We conclude that, in our hands, ultrasonography is not useful in differentiating patients with MH from normal persons.