Investing abdominal fascia

The investing abdominal fascia is the fascia of abdomen that envelops the external and internal oblique muscles and the transversus abdominis. The investing abdominal fascia was previously divided into three layers into the Terminologia Anatomica 1 and source of confusion that's why these layers are not anymore officialy listed anymore in Terminologia Anatomica 2):

• The superficial investing abdominal fascia that covers the external surface of external oblique muscle and forms the suspensory ligament of clitoris/ penis. Some sources called this superficial investing abdominal fascia with the eponym "Gallaudet's fascia", but this eponym is already used for the perineal fascia, which is confusing.

• The intermediate investing abdominal fascia that covers the internal oblique muscle: it is composed by two layers of fascia, one internal and one external to the internal oblique muscle. The internal layer is formed by the fascia investing the external surface of the transversalis muscle and the fascia covering the internal surface of the internal oblique muscle (the two fasciae coalesce.) The external layer is given from the fasciae investing the external surface of the internal oblique and the internal surface of the external oblique muscle.

• The deep investing abdominal fascia that covers the transversalis muscle: for some authors, the deep investing abdominal fascia and the fascia transversalis are the same structures (Transversalis fascia is the inner epimysium of transversus abdominis muscle; no separate deep investing fascia exists).