Alternate Names : BOO, Lower urinary tract obstruction, Prostatism
Bladder outlet obstruction (BOO) is a blockage at the base of the bladder that reduces or prevents the flow of urine into the urethra, the tube that carries urine out of the body.
Overview, Causes, & Risk Factors
Bladder outlet obstruction can have many different causes, including:
- Benign prostatic hyperplasia (BPH)
- Bladder stones
- Bladder tumors (cancer)
- Pelvic tumors (cervix, prostate, uterus, rectum)
- Urethral stricture (scar tissue)
Less common causes of bladder outlet obstruction include:
- Foreign objects
- Posterior urethral valves (congenital birth defect)
- Urethral spasms
- Urethral diverticula
Bladder outlet obstruction is most common in aging men. It is often caused by BPH. Bladder stones and bladder cancer are also more commonly seen in men than women. As a man ages, the chance of developing these diseases increases dramatically.
- Benign prostatic hypertrophy
- Bladder stones
- Obstructive nephropathy
- Reflux nephropathy
Pictures & Images
Female urinary tract
The female and male urinary tracts are relatively the same except for the length of the urethra.
Male urinary tract
The male and female urinary tracts are relatively the same except for the length of the urethra.
Kidney – blood and urine flow
This is the typical appearance of the blood vessels (vasculature) and urine flow pattern in the kidney. The blood vessels are shown in red and the urine flow pattern in yellow.
Review Date : 11/30/2009
Reviewed By : David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Herbert Y. Lin, MD, PHD, Nephrologist, Massachusetts General Hospital; Associate Professor of Medicine, Harvard Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.