Nonpalpable testes: is there a relationship between ultrasonographic and operative findings?

Ultrasonography (US) as a diagnostic tool in the work-up of boys with nonpalpable testes (NPT) is still controversial.

To evaluate the relation between US and operative findings in boys with NPT.

During a 7-year period we saw 135 boys with 152 NPT. All were examined by the referring physician or a paediatric surgeon, underwent US examination, and were then re-examined afterwards by a specialist. Finally, all boys were surgically explored for testicular position.

US located 103 NPT (68%), 16 within the abdomen and 87 in the inguinal canal. With knowledge of the US result, 37 testes were palpable on re-examination. The sensitivity of US was 97% for inguinal and 48% for abdominal viable testes. Of the 49 testes (32%) missed by US, 16 were viable in either the abdominal (n=14) or the inguinal (n=2) position.

All boys with presumed NPT should be referred to a specialist. US is useful to determine localization of NPT, which facilitates planning the surgical procedure. An inguinal exploration is called for when US identifies the testis in the inguinal canal. Because the sensitivity of US for viable abdominal testes is only 48%, we now always perform laparoscopic exploration when US is negative.