The role of sonography in the detection of vaginal foreign bodies in young girls: the bladder indentation sign.

The cases of four young girls with vaginal foreign bodies, successfully diagnosed by ultrasound, are presented. The sonographic signs include varying echogenicity and acoustic shadowing, but always an indentation of the posterior bladder wall was clearly observed. Sonography should be considered as the first step in the evaluation of suspected vaginal foreign bodies in young girls.