Prostatic reflux: a simple radiographic sign in recognizing dysfunctioned voiding from external sphincter disorders.

Clinical and urodynamic studies of urethroprostatic reflux were performed in 15 of 40 paraplegics subjected to voiding cystourethrography in the last 5 years. Failure of the external urethral sphincter to relax was confirmed in all patients by either sphincter electromyography or documentation of sympathetic dyssynergia, and high pressure in the prostatic urethra was confirmed by measurement of voiding pressure. A shrewd search for this simple radiographic sign was suggested in the followup of paraplegics because it often served as an early indicator of exposure of the urinary system to the brunt of voiding under high pressure, which presently is believed to be more detrimental to the patients than residual urine. We discuss briefly an anatomical basis for its occurrence preferentially in the peripheral lobe as well as in the central lobe of the prostate in some advanced cases.