Ultrasound for the detection of foreign bodies in human tissue.
OBJECTIVE
To determine the accuracy of detection of wood and plastic foreign bodies in human tissue by relatively inexperienced clinicians using typical ultrasound equipment.


METHODS
Uniform wood and plastic foreign bodies were placed through small punctures into recently amputated human legs. Identical control punctures contained no foreign bodies; the sequence of foreign bodies and controls for the puncture sites was randomized. A second blinded investigator scanned each puncture site with a 7.5-MHz ultrasound probe to determine the presence or absence of foreign material.


RESULTS
Eighty punctures were scanned. Ultrasound detected 44 of 53 foreign bodies (83% sensitivity). Wood foreign bodies were detected 25 of 27 times (93%) and plastic foreign bodies 19 of 26 times (73%; P = 13). Overall, there were 11 false-positive readings (59% specificity).


CONCLUSIONS
Ultrasound is imperfect but may be useful in screening for superficial foreign bodies in human tissue. Clinical utility in the ED setting remains to be tested.
Hill
R
R
Department of Emergency Medicine, St Luke's Hospital, Bethlehem, Pennsylvania, USA.
Conron
R
R
Greissinger
P
P
Heller
M
M
D016009:Chi-Square Distribution; D004635:Emergency Medicine; D005189:False Positive Reactions; D005547:Foreign Bodies / Q000000981:diagnostic imaging*; D006801:Humans; D007396:Internship and Residency; D007869:Leg Injuries / Q000000981:diagnostic imaging*; D010969:Plastics; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D014934:Wood
D010969:Plastics