Radiologic Anatomy of the Inguinofemoral Region: Insights from MDCT

Abstract

OBJECTIVE: We set out to reexamine the radiologic anatomy of the inguinofemoral region using volume data sets obtained with an MDCT scanner. MATERIALS AND METHODS: We conducted a systematic prospective review of CT scans of 20 consecutively enrolled patients, 10 men and 10 women chosen retrospectively from our CT database. An experienced radiologist and a senior trainee surgeon conducted an image review to maximize recognition of relevant anatomic detail. RESULTS: The inferior epigastric artery and femoral canal were identified in all planes in all patients. On axial views a spur on the pubic bone was visible in 17 (85%) of the patients, but the inguinal ligament was not reliably identified in any. The round ligament or spermatic cord was visible in only 15 (75%) of 20 patients. In contrast, on coronal and sagittal views, the inguinal ligament, which is vital to reliable identification and accurate classification of groin hernias, was visible in 19 (95%) of the 20 patients. Scans in the sagittal plane best depicted the gutter-like aspect of the ligament, the canal and contents being clearly visible in 95% of the patients. On sagittal views, the internal ring was identifiable in 90% and the round ligament or spermatic cord in 95% of the patients. On coronal images, the internal ring was identified in all and the conjoint tendon in 95% of the patients. The round ligament or spermatic cord was not seen in 10% of the patients. CONCLUSION: MDCT produces images of the inguinal region in detail not possible with previous generations of scanners. In our small series, 100% identification of key anatomic structures was achieved when information from all three views was combined. We found subtle differences between imaging findings and standard anatomic teaching.