Detecting Incisional Hernia at Clinical and Radiological Examination

In clinical studies, incisional hernia is usually diagnosed by clinical examination. No other modality has been proven an aid in the diagnosis. The aim was to investigate the correlation between findings at clinical examination and at computed tomography when detecting incisional hernia after midline incisions.

Patients underwent clinical examination by three surgeons. Computed tomography was performed in both the supine position and in the prone position and was examined by three radiologists. The correlation between investigators and methods were estimated by calculating the Fleiss Kappa values.

Twenty-four patients were assessed. For the clinical examination, the Kappa was 0.81. For computed tomography with the patient in the supine position, the Kappa was 0.94 and in the prone position it was 0.89. The Kappa for clinical examination and computed tomography combined was 0.80.

At clinical examination, incisional hernia can be defined as any detectable defect in the abdominal wall with intra-abdominal contents protruding beyond the aponeurosis. The same definition can be used at computed tomography with the addition that any visible hernia sac is also regarded an incisional hernia. With this definition, there is very good agreement between investigators at clinical investigation and at computed tomography in the prone or in the supine position. The highest agreement among investigators is achieved with computed tomography in the supine position. In clinical studies, clinical examination seems adequate for diagnosing herniation but in overweight patients a CT-scan may be a further aid.