Clinical and symptomatic variables are very useful for the initial evaluation of patients; however, it has been shown that they do not correlate with bladder outlet obstruction
, or its degree .
Ultrasound assessment of intravesical prostatic protrusion and detrusor wall thickness-new standards for non-invasive bladder outlet obstruction
The urologic nurse practitioner requested urodynamic evaluation to determine whether his weak urinary stream and incomplete bladder emptying were caused by bladder outlet obstruction
, underactive detrusor function (poor detrusor contraction strength), or a combination of these factors.
We also recommend that uroflowmetry and post-void residual urine be considered an integral part of the initial evaluation because there is no other way to screen for bladder outlet obstruction
. In a prior publication, the authors demonstrated that over 90% of men with OAB symptoms have concomitant urological conditions that should be considered in the differential diagnosis.
The voiding urethrogram is an essential component of any videourodynamic evaluation that includes a voiding pressure flow study, especially when evaluating the patient with bladder outlet obstruction
. While routine multichannel urodynamics testing enables the clinician to identify and assess the severity of obstruction and the presence of vesicosphincter dyssynergia when pelvic floor EMG is assessed, videourodynamic imaging allows the clinician to localize the level of obstruction and the associated etiology.
Voiding function is often defined by the bladder outlet obstruction
index (BOOI) and bladder contractility index (BCI).
Multiple methods have been developed for evaluating urethral resistance and bladder outlet obstruction
based on analysis of the X-Y plot (see Table 1).
Partial bladder outlet obstruction
(pBOO) is a ubiquitous problem in urology and can result in significant morbidity and mortality.
In small or moderate stones, endoscopic procedures such as optical mechanical cyst lithotripsy have an added advantage as it can be combined with corrective procedure for the cause of bladder outlet obstruction
. Zhaowu et al (1988) have recommended that electrohydraulic shockwave lithotripsy (ESHWL) preferably to be avoided in large, hard bladder stones and diverticular stone or when a stone is stuck to the mucosa.
Reynard, Lim, Swami, and Abrams (1996) compared the effect of 8-French catheters versus no catheters in a group of 59 men with varying degrees of bladder outlet obstruction
and found no statistically significant results when the Qmax rates were compared.
Transurethral incision of the prostate (TUIP) is a well-established treatment for bladder outlet obstruction
(BOO) secondary to small-size benign prostate enlargement (BPE).
Cystoscopy may be required to evaluate bladder outlet obstruction
if the patient is not voiding.