Utility of ultrasonography in hair-thread tourniquet syndrome.

A 2-year-old girl presented with a 2-month history of an erythematous, indurated plaque with well-defined borders on the third toe of the right foot. Bedside high-resolution ultrasonography demonstrated a thickened epidermis overlying a hyperechoic focus within the dermis. Her clinical and sonographic presentation was in keeping with a foreign body causing hair-thread tourniquet syndrome. The foreign body was surgically extirpated without neurovascular sequelae. Ultrasonography expedited accurate diagnosis and is a promising adjunct to clinical evaluation for radiolucent foreign bodies.