From the Research
The best imaging modality to diagnose an inguinal hernia is ultrasound, as it offers high sensitivity and specificity, and is non-invasive, cost-effective, and widely available. When performing an ultrasound for suspected inguinal hernia, the patient should be examined both in supine and standing positions, and the Valsalva maneuver should be used to provoke the hernia if it's not immediately visible, as shown in a study published in 2020 1. Ultrasound can effectively identify the hernia sac, its contents, and differentiate between direct and indirect inguinal hernias. The high-level specificity (0.9980) and sensitivity (0.9758) of ultrasound in diagnosing inguinal hernias were demonstrated in a study published in 2017 2.
Some key points to consider when using ultrasound to diagnose inguinal hernias include:
- The use of high-frequency, small-part linear transducers to accurately display femoral and small or occult groin hernias 2
- The importance of operator expertise in performing ultrasound examinations for hernia disease 1
- The ability of ultrasound to visualize soft tissue structures in the groin area and assess hernia reducibility and real-time observation of the dynamic nature of hernias during various maneuvers and positions
In cases where ultrasound results are inconclusive or when complications are suspected, MRI can be used as a second-line imaging option, particularly for occult hernias or complex cases, as suggested in a study published in 2014 3. CT scans are generally reserved for emergency situations when strangulation or bowel obstruction is suspected. The most recent and highest quality study, published in 2022 4, also supports the use of ultrasound as the primary imaging modality for diagnosing inguinal hernias, due to its convenience, portability, and lack of radiation.