The Efficiacy of Sternocleidomastoid Muscle Flap on Frey's Syndrome via a Novel Test: Galvanic Skin Response

The aim of this study was to evaluate the effects of sternocleidomastoid (SCM) muscle flap on preventing Frey's syndrome by using, Galvanic skin responses (GSR). Fourty-three patients who underwent superficial parotidectomy were randomly divided into two groups and their GSR were recorded. SCM muscle flap was applied over the surgical area only in one group. Six months after the surgery, GSRs were remeasured. In addition, the patients completed a questionnaire regarding their complaints about clinical Frey's syndrome. Four patients had symptoms of clinical Frey's syndrome. Postoperative GSR measurements revealed no significant difference between two sides in flap group (p = 0.426) but higher in without flap group (p = 0.003). The patients with clinical Frey syndrome had significantly higher GSR values than the remaining patients. The SCM muscle flap was an effective method in preventing Frey's syndrome. Moreover, GSR test was highly sensitive and specific for diagnosis.