Post-void in ultrasound refers to the post-void residual (PVR) measurement—the volume of urine remaining in the bladder after urination. A bladder ultrasound noninvasively estimates this to assess bladder emptying and detect urinary retention. It's used when evaluating incontinence, benign prostatic hyperplasia, neurogenic bladder, or recurrent UTIs; values under about 50–100 mL are generally considered acceptable.

Normal post-void residual (PVR) urine is generally less than 50 mL. Up to about 100 mL may be acceptable in older adults, but volumes >100 mL suggest incomplete bladder emptying and warrant evaluation; volumes above 200 mL are usually clinically significant. PVR is measured by bladder ultrasound or catheterization and interpreted alongside symptoms and clinical context.

An ultrasound of the abdomen with post-void residual is a noninvasive scan using sound waves to image abdominal organs and measure bladder emptying. The bladder is imaged before and after urination to calculate post-void residual volume, which helps detect urinary retention, incomplete emptying, causes of incontinence, or assess treatment response. It’s quick, painless, and involves no radiation.

Treat post-void urinary retention by confirming residual volume with a bladder scan and relieving acute retention via catheterization (urethral or suprapubic). For chronic cases, clean intermittent catheterization or a long-term suprapubic catheter may be used. Address underlying causes—stop offending drugs, treat infections, consider alpha‑blockers for BPH, pelvic‑floor therapy, or surgical relief if obstruction persists, with regular monitoring.

Void refers to the act of emptying the bladder, i.e. urination. Post-void means the period immediately after urination and is used in terms like post-void residual (the urine remaining in the bladder after voiding) or post-void dribble (small leakage after finishing). Measuring post-void residual helps assess bladder emptying and identify urinary retention or other lower urinary tract problems.

Post-void residual (PVR) in a female is the volume of urine left in the bladder after urination. It’s measured by bladder ultrasound or catheterization. Normal PVR is generally low (often <50–100 mL); higher volumes indicate incomplete emptying and possible urinary retention from pelvic organ prolapse, obstruction, detrusor underactivity, or neurologic disease. Elevated PVR raises risk of urinary infection and may need further evaluation.