Differentiation of a Femoral Hernia from an Inguinal Hernia on Isotropic Multidetector-Row CT (MDCT): the Benefit of Inguinal Ligament Coronal-Oblique Images

Abstract

Purpose: This study was designed to evaluate the diagnostic value of the use of inguinal ligament coronal-oblique CT images in the differentiation of femoral hernias from inguinal hernias. Materials and Methods: A total of 32 patients (with 11 femoral hernias and 21 inguinal hernias) underwent CT imaging. All of the examinations were performed with a 16multidetector row CT (MDCT) scanner with contrast enhancement, and transverse sections, coronal sections and coronal-oblique CT images were reformed along an imaginary inguinal ligament plane. Two independent observers retrospectively evaluated the CT scans. Image analysis was first performed with only transverse and coronal images. A second analysis was then performed with transverse, coronal and coronal-oblique images. Results: The mean angle difference between coronal and coronal-oblique CT images was 8.0 degrees (range, 0-22 degrees). A radiologist correctly diagnosed the presence of a femoral hernia in nine (82%) of 11 patients and a radiology fellow correctly diagnosed the presence of a femoral hernia in seven (64%) of 11 patients in the first session. Both of the reviewers made the correct diagnosis in all patients in the second session. For inguinal hernias, both reviewers correctly diagnosed all patients during both sessions. The coronal-oblique CT images were the most valuable images for the evaluation of the relationship between hernias of the neck and inguinal ligament. Conclusion: Inguinal ligament coronal-oblique CT images can provide additional diagnostic value in the evaluation of groin hernias.