Pitfalls related to the urinary bladder in pelvic sonography: a review

A number of pitfalls related to the urinary bladder may be encountered during ultrasound examination of the pelvis. Examples of particularly difficult or frequently encountered situations are illustrated in this report. In our experience, difficulties most commonly arise from incorrect identification of the urinary bladder, with an abnormal cystic pelvic mass simulating the normal urinary bladder, or vice versa. In addition, confusing appearances may be caused by urine refluxed into the vagina, technical artifacts, bladder diverticula, or mobile pelvic masses displaced by the bladder. Definitive bladder identification is useful to avoid errors in situations likely to be associated with bladder related pitfalls.