Increased filling sensation: increased sensation at low volumes in absence of involuntary contractions, leads to decreased “functional” but not anatomic bladder capacity
Intrinsic sphincter deficiency (ISD): leak point pressure less than 60cm water or MUCP less than 20cm water
Neurogenic bladder (NGB): abnormal bladder function due to neurologic disease
Occult SUI: SUI only after reduction of co-existent prolapse
Pelvic organ prolapse (POP): descent of anterior/posterior vaginal wall, uterus, vaginal apex
Reduced filling sensation: decreased sensation throughout bladder filling
Stress urinary incontinence (UDS): involuntary leakage during filling associated with increased intraabdominal pressure in the absence of detrusor contraction (AKA low VLPP)
Detrusor pressure should remain near zero until voiding is initiated
Pdet can differentiate between Valsalva and true detrusor contraction
Impaired compliance: > 40, needs treatment to prevent upper tract injury, may be artificially decreased if reflux or diverticulum present
Abdominal leak point pressure (ALPP): ability of sphincter to resist changes in abdominal pressure, can only be seen with SUI, < 60 indicates ISD, > 90 indicates minimal/no ISD
CLPP and VLPP are both ways to measure ALPP, but VLPP tends to be lower
Detrusor leak point pressure (DLPP): lowest detrusor pressure where leakage occurs in absence of detrusor contraction or increased abdominal pressure, higher value implies pressure transferred to upper tracts instead of inducing leakage
Stress induced detrusor overactivity (SIDO): triggered by rise in abdominal pressure
Detrusor overactivity
Urodynamic finding, may (not) be unrelated to OAB symptoms
Seen in 14-18% normal patients, 50% who report urge incontinence may not demonstrate DO on UDS
Terminal: occurs at cystometric capacity resulting in incontinence and possible bladder emptying
Only 60-70% men and 40-50% with dry OAB demonstrate DO, whereas 90+% men with wet OAB will demonstrate DO
Coexistent BOO may affect efficacy of OAB treatments (cause urinary retention), but OAB symptoms may improve if BOO is treated
Terminal DO at diminished capacity is most likely predictor that OAB symptoms will persist after treating BOO
Emptying phase
Normal voiding: relaxation of striated sphincter, detrusor contraction, opening of bladder neck and urethra, onset of urination
Minimum volume 150mL recommended to assess uroflow curve
Detrusor underactivity (DUA): low pressure and low flow, reduced contraction strength leading to prolonged emptying time
Detrusor acontractility: no detrusor contraction on UDS
Bladder outlet obstruction: high pressure and low flow
If no SUI demonstrated on UDS, remove catheter and repeat test (may be obstructing) - up to 50% women (and 35% men) with SUI symptoms but no SUI on UDS show SUI once catheter removed
If prolapse present, reduce (pessary, vaginal pack) and repeat stress testing (occult SUI)
Mixed incontinence without DO on UDS shows greater improvement after SUI surgery compared with OAB treatment
OAB, UUI, and Mixed Incontinence
Consider UDS prior to surgical or irreversible treatments for OAB
Consider if new or persistent urge symptoms after bladder outlet procedure