Ultrasound bladder scanner presents falsely elevated postvoid residual volumes.

Case description An 83-year-old woman with severe Alzheimer dementia was admitted with verbal and physical aggression to the acute Care of the Elderly unit. Because the patient had incontinence, postvoid residual (PVR) volumes were measured using a portable ultrasound bladder scanner. Postvoid residual urine volumes, measured on several different occasions, ranged from 403 to 855 mL, with only 75 to 200 mL drained by in-and-out catheterization. As a result of this discrepancy, an abdominal and pelvic ultrasound was done. This demonstrated a great number of bilateral cystic lesions around the left kidney and a complex cystic lesion in the pelvis. Subsequently, the patient underwent a computed tomographic (CT) scan of the abdomen and pelvis. This revealed at least 10 cystic lesions on the left kidney, the largest of which measured 11 x 12 x 14 cm, extending from the lower pole of the left kidney and into the pelvic region (Figure 1). Ovarian cystic lesions were also seen on the pelvis (Figure 2). All the cystic lesions were consistent with benign simple cystic lesions.