Paradigm shift regarding the transversalis fascia, preperitoneal space, and Retzius' space.

BACKGROUND: There has been confusion in the anatomical recognition when performing inguinal hernia operations in Japan. From now on, a paradigm shift from the concept of two-dimensional layer structure to the three-dimensional space recognition is necessary to promote an understanding of anatomy. ANATOMY AND EMBRYOLOGY: Along with the formation of the abdominal wall, the extraperitoneal space is formed by the transversalis fascia and preperitoneal space. The transversalis fascia is a somatic vascular fascia originating from an arteriovenous fascia. It is a dense areolar tissue layer at the outermost of the extraperitoneal space that runs under the diaphragm and widely lines the body wall muscle. The umbilical funiculus is taken into the abdominal wall and transformed into the preperitoneal space that is a local three-dimensional cavity enveloping preperitoneal fasciae composed of the renal fascia, vesicohypogastric fascia, and testiculoeferential fascia. The Retzius' space is an artificial cavity formed at the boundary between the transversalis fascia and preperitoneal space. In the underlay mesh repair, the mesh expands in the range spanning across the Retzius' space and preperitoneal space.

Laparoscopic resection of a retroperitoneal schwannoma.

Herein is a report of a case of a 34-year-old man whose chief complaint was right lower abdominal pain. He was diagnosed with acute appendicitis. Additionally, an abdominal CT scan found retroperitoneal tumor approximately 5 cm in size, with an imaging effect, located adjacent to the dorsal side of the inferior vena cava. For this suspected neurogenic tumor, laparoscopic appendectomy and retroperitoneal tumorectomy were performed after conservative treatment of appendicitis. The retroperitoneal tumor was 5.5 × 3.5 cm in size, had a capsule, smooth surface and soft elasticity, and the divided face was solid white. The histopathological work-up revealed that the tumor was a benign mixed-type schwannoma, in which spindle cells were arranged. The patient's postoperative course was uneventful, and he was discharged from the hospital 7 days after the surgery. In general, retroperitoneal schwannoma is not associated with any symptoms, so it is often discovered accidentally, as in this case. The appropriate treatment for the condition is surgical resection of the tumor including the capsule. However, the use of laparoscopic surgery has been reported in recent years. Although the majority of the cases are benign, there have been some reports of local recurrence. As such, this case will required careful follow-ups.

Delayed left traumatic diaphragmatic hernia repaired by laparoscopic surgery.

A 77-year-old man injured himself when he fell heavily on the left side of his chest. He had massive subcutaneous emphysema, bleeding, and left hemopneumothorax. He also fractured his seventh through tenth ribs; a fragment of the ninth rib was displaced into the thoracic cavity. The severity of the damage and the patient's pain was assessed using the Abbreviated Injury Scale 1990 (1998 update) as level 3. He was treated with conservative therapy and discharged on the 16 days after the injury. However, the following day, he had acute upper abdominal pain, his blood pressure dropped to 40 s, and he was readmitted. A chest CT showed the transverse colon was prolapsed in the thoracic cavity. The patient was diagnosed as having a delayed traumatic diapharagmatic hernia. A laparoscopic repair was performed. The rupture was classified as a IIIb-type diaphragmatic injury according to the Japanese Association for the Surgery of Trauma's classification system. It is believed that a fragment of a fractured rib that had been displaced in the thoracic cavity ruptured the diaphragm sharply. Since traumatic diapharagmatic hernia rarely occurs, it is relatively difficult to diagnose at the first examination. This condition has a high mortality rate because of the associated injuries. Surgery is the only treatment, but it should only be considered after a second examination. Herein, I report my experience with a case of delayed diaphragmatic hernia repaired by laparoscopic surgery.