Bandl ring
A Bandl ring may be seen during imaging of a patient in labor.
Epidemiology
It is considered to be an uncommon finding in modern obstetrics (0.01-1.26%).
Pathology
It is a pathologic retraction ring at "Barnes boundary line", which separates the upper contractile portion of the uterus from lower uterine segment. The constriction prevents the fetus from orienting toward the cervical os and obstructs normal labor.
Radiographic features
Ultrasound and MRI
- uterine constriction at the junction of the thinned lower uterine segment with a thickened, retracted upper uterine segment
Treatment and prognosis
May necessitate cesarean section to avoid potential uterine rupture.
History and etymology
Named after L Bandl, a Viennese obstetrician.