Ovarian Cystadenoma Mistaken as Postvoid Residual Urine by Portable Ultrasound Scanning.

1)Determination of postvoid residual (PVR) is necessary for the evaluation of lower urinary tract dysfunction. Since sonography has been the standard tool for the assessment of PVR, a portable, automated device (BladderScan) produced measurements of PVR that correlated well with catheterized volumes in most studies [1-4]. However, portable ultrasound is not as specific for urinary retention as it is sensitive, of which false-positive rate was upto 9% even in the most favorable series [4]. This relatively low specificity is maybe because BladderScan does not appear to distinguish between residual urine and their fluid collections in the pelvis and lower abdomen [5]. We report a case involving false-positive elevated PVR results on a bladder ultrasound caused by an ovarian cystadenoma.