The role of ultrasound scan in the diagnosis of occult inguinal hernias

Aims: The aim of this study is to examine the role of ultrasound in conjunction with clinical judgment in diagnosing occult inguinal hernias in patients with groin pain.

Methods: The study involved a retrospective analysis of 297 patients who presented over an 18 month period from January 2007 to August 2008. All the patients presented to outpatient clinic with groin pain but a normal or equivocal clinical examination. Data was obtained from hospital records, radiology system and operation notes.

Results: 167 examinations (56%) were positive for a hernia, as a result of which 116 patients underwent surgery. At surgery, a hernia was found in 85 cases and no hernia was found in 31 cases. 130 examinations (44%) were negative for hernia. Six patients proceeded to surgery despite a negative ultrasound due to ongoing pain and a hernia was found in 5 cases. Overall, correlation with surgical findings showed ultrasound to have a sensitivity of 94%. Ultrasound used with clinical judgment has a positive predictive value of 73%.

Conclusions: Ultrasound scan alone in diagnosing groin hernias is not effective when correlated with operative findings. However in conjunction with clinical judgment it is a useful tool in diagnosing occult inguinal groin hernias and aiding in further management.