Internal supravesical hernia accompanied with anomalous fold formations: a cadaveric case report

During the abdominal dissection of a 67-year-old male cadaver, an unusual peritoneal fold was encountered on the inner surface of the anterior abdominal wall. The peritoneal fold had two parts: the anterior part was located at the midsagittal plane including dispersed urachus remnants, the other part was located at the coronal plane with a triangular shape at the posterior edge of the sagittal part. Remnants of the umbilical arteries were ascending in the lateral margins of the coronal part. Accordingly, two peritoneal sacs were formed on both sides of this abnormal fold. Part of the small bowel herniated into the left peritoneal sac situated on the left side of the bladder. Although the aperture of the hernia sac was at the lateral side of the remnant of the umbilical artery which is concordant with the normal position of the medial inguinal fossa, the bottom of the sac was found to be located at the supravesical region. Therefore, this case was interpreted as an internal supravesical hernia with an unusual course. Although these rarely seen internal supravesical hernias in the literature were reported to be observed either preoperatively or postoperatively, to our knowledge our case is the first to be revealed in a cadaver which in detail enabled us to examine the features of this unique peritoneal variation and accompanying anatomic structures that caused hernia formation.