Lateral decubitus positioning allows shifting of internal echoes within the bladder, helping differentiate mobile debris (such as blood clots or sediment) from adherent masses like tumors. This technique is helpful in evaluating questionable bladder filling defects.

According to Rumack’s Diagnostic Ultrasound:

“Changing the patient’s position, such as turning to the lateral decubitus, can help distinguish mobile debris from attached bladder wall lesions.”