13. Videourodynamics : Combines measurement of intravesical intraabdominal and striated urethral sphincter pressures with bladder filling, bladder emptying, and flow rate, all done simultaneously with fluoroscopy
14. Sacral evoked responses
a. This test quantitates the integrity of the innervation of the striated pelvic floor and perineal muscles along with the supraspinal pathways involved in lower urologic tract function.
b. The nerve conduction time (latency) and the stimulation threshold are the two parameters most commonly measured.
c. Bulbocavernosus reflex latency is clinically measured. Normal is 30 to 40 msec.
d. Any neurologic process that interferes with the integrity of the reflex arc will result in a prolonged latency.
e. The following are common disorders associated with prolonged latency:
(1) Diabetes mellitus
(2) Alcoholic neuropathy
(3) Disc disease
15. Abdominal-valsalva leak point pressures
a. This measures the amount of abdominal pressure required to induce urinary leakage. A normal patient should remain continent regardless of the amount of abdominal pressure exerted on the lower urinary tract.
b. This is used to document type III incontinence, associated with an incompetent sphincter.
(1) These patients leak at low to moderate abdominal pressures.
(2) Patients with types I and II incontinence require higher abdominal pressures to leak.
c. The abdominal-valsalva leak point pressure is the change in intravesical pressure documented before the valsalva maneuver to the pressure at which incontinence occurs.
d. Abdominal-valsalva leak point pressures.
(1) Greater than 120 cm H2O: Type I incontinence is characterized by the bladder neck gradually opening with heavy exercise or exertion. There is support for the pelvic floor and no movement of the bladder neck. Treatment: medication.
(2) 60 to 100 cm H2O: Type II incontinence is characterized by bladder neck hypermobility with herniation through the pelvic floor with straining, disrupting the ability of the bladder to remain closed. Treatment: bladder neck suspension.
(3) Less than 60 cm H2O: Type III, or intrinsic sphincter deficiency, is characterized by a dysfunctional bladder neck and proximal urethra. Treatment: pubovaginal sling, an injectable agent, or an artificial sphincter.
Typical videourodynamic system