Isthmus of uterus
Isthmus uteri
Definition
On the surface of the uterus, about midway between the apex and base, is a slight constriction, known as the isthmus, and corresponding to this in the interior is a narrowing of the uterine cavity, the internal orifice of the uterus. The portion above the isthmus is termed the body, and that below, the cervix.
For some authors, the term "isthmus of uterus" concerns only the narrowing of the uterine cavity, between the body part of uterine cavity and the cervical canal.
References
