Efficacy of diagnostic ultrasonography of lipomas, epidermal cysts, and ganglions.

OBJECTIVE: To determine the efficacy of ultrasonography for the diagnosis of subcutaneous benign lesions.

DESIGN: Retrospective study.

SETTING: Tokyo Kousei-Nenkin Hospital, Tokyo, Japan. Patients The study included 183 patients with subcutaneous benign lesions who underwent ultrasonography and then received a pathologic diagnosis after surgery.

MAIN OUTCOME MEASURES: The study evaluated the number of cases in which the preoperative diagnosis after ultrasonography or just after palpation agreed with the pathologic diagnosis.

RESULTS: Ultrasonography significantly increased the preoperative diagnostic yield of subcutaneous benign lesions (after palpation, 29%; after ultrasonography, 46%; P < .001). The sensitivity for the diagnosis of lipoma (after palpation, 54.8%; after ultrasonography, 88.1%; P < .01) and the specificity for the diagnosis of epidermal cyst (after palpation, 93.5%; after ultrasonography, 99.3%; P < .05) significantly increased after ultrasonography. The sensitivity for the diagnosis of epidermal cyst and ganglion also tended to increase after ultrasonography. Conclusion The study results suggest that ultrasonography is useful for the preoperative examination of subcutaneous benign lesions.