The influence of ultrasound in the choice of surgical technique to repair inguinal hernia: a prospective multicentric cohort study

Background: Inguinal hernia is diagnosed by physical evaluation alone in most patients. Although imaging should be reserved for equivocal physical findings, a previous cohort study described a high rate of ultrasound usage. This study aimed to explore the association between ultrasound usage and the choice of surgical technique to repair inguinal hernia. Methods: This was a multicentre prospective cohort of consecutive patients undergoing elective inguinal hernia repair between October and December 2019. The group of patients diagnosed with physical evaluation was compared to the group diagnosed with ultrasound. Patients undergoing other imaging tests were excluded. The primary outcome was surgical technique and a multivariable logistic regression model was used to test its association with ultrasound use. Results: A total of 911 patients from 33 Portuguese hospitals were included, of which 49.2% (448) were diagnosed with physical evaluation and 50.8% (463) with ultrasound. There were no statistically significant differences in the characteristics of the patients, symptoms or hernia type between the two groups. Lichtenstein was the most used surgical technique in both groups. There was no association between the use of ultrasound and the choice of surgical technique (adjusted odds ratio 1.02, 0.71-1.48, p=0.901). Conclusions: Although ultrasound is not recommended routinely for diagnosing inguinal hernia, it was used in half of the patients and demonstrated no impact on the choice of surgical technique. A national intervention needs to be planned to decrease the use of ultrasound in inguinal hernia, reducing the costs for the patients and the healthcare system.