排尿障礙治療中心版權所有 Urodynamics and Bladder Outlet Obstruction Hann-Chorng Kuo Department of Urology Buddhist Tzu Chi General Hospital

排尿障礙治療中心版權所有

Urodynamics and Bladder Outlet Obstruction

Hann-Chorng KuoHann-Chorng Kuo

Department of UrologyDepartment of Urology

Buddhist Tzu Chi General HospitalBuddhist Tzu Chi General Hospital


Bladder Outlet Obstruction

BOO occurs in both women and menBOO occurs in both women and men The most frequent clinical problem in aging The most frequent clinical problem in aging

malesmales BOO can be progressive, results in bladder iBOO can be progressive, results in bladder i

rritation, compensation,and decompensationrritation, compensation,and decompensation


Benign prostatic enlargement


Storage and Empty Symptoms related to BOO Bladder dysfunction or outlet obstructionBladder dysfunction or outlet obstruction Increased frequency day or nightIncreased frequency day or night Urgency or urge incontinenceUrgency or urge incontinence Hesitancy and reduced urinary streamHesitancy and reduced urinary stream Intermittency and postvoid dribblingIntermittency and postvoid dribbling Urinary retentionUrinary retention Upper tract dilatation, bladder stone, uremiaUpper tract dilatation, bladder stone, uremia Urinary tract infectionUrinary tract infection


Detrusor Changes after BOO

Irritative stage: detrusor hypertrophy, uninhibited Irritative stage: detrusor hypertrophy, uninhibited detrusor contractionsdetrusor contractions

Compensation stage: Detrusor hypertrophy, trabecCompensation stage: Detrusor hypertrophy, trabeculation, pseudodiverticulum, increased urethral resulation, pseudodiverticulum, increased urethral resistance, increased residual urine, stenosis at UVJ, istance, increased residual urine, stenosis at UVJ, bilateral hydroureter and hydronephrosisbilateral hydroureter and hydronephrosis

Decompensation stage: overdistended, over-flow iDecompensation stage: overdistended, over-flow incontinence, renal function is decreasedncontinence, renal function is decreased


Bladder Filling Phase

Laplace’s law: T = Pdet R (Tension= detrusor presLaplace’s law: T = Pdet R (Tension= detrusor pressure x radius of bladder)sure x radius of bladder)

Low frequency micromotion of detrusor exist in blLow frequency micromotion of detrusor exist in bladderadder

Regional spontaneous contractions cause only sligRegional spontaneous contractions cause only slight changes of stress in bladder wallht changes of stress in bladder wall

Bladder filling at 0.5-1ml/min (F.S. 300ml)Bladder filling at 0.5-1ml/min (F.S. 300ml) Rapid stretch (i.e. diuresis) can cause a sensation oRapid stretch (i.e. diuresis) can cause a sensation o

f fullness at a small volume (F.S. 150ml)f fullness at a small volume (F.S. 150ml)


Rhythmic Detrusor Contractions after Resiniferatoxin treatment


Voiding Phase

Voiding process starts from relaxation of exVoiding process starts from relaxation of external sphincter followed by detrusor contraternal sphincter followed by detrusor contractionction

At the opening pressure, flow startsAt the opening pressure, flow starts Urethral compliance allows increased flow tUrethral compliance allows increased flow t

hrough increasing Pdethrough increasing Pdet Urethral obstruction reduces compliance anUrethral obstruction reduces compliance an

d reduces flow increased reduces flow increase


Initiation of VoidingThe Relationship of Q and Pdet


Initiation of VoidingActive relaxation of External sphincter


Initiation of VoidingPassive opening of urethral wall


Urethral Compliance

Not constant during voidingNot constant during voiding Passive viscoelastic property of urethral walPassive viscoelastic property of urethral wal

ll Active properties of urethral smooth muscle Active properties of urethral smooth muscle

and periurethral external sphincterand periurethral external sphincter Pdet= Puo + QPdet= Puo + Q2 2 / c/ c

c= coefficient of urethral compliancec= coefficient of urethral compliance


Bladder Pressure

Intravesical pressure (Pves) = intra-abdominal preIntravesical pressure (Pves) = intra-abdominal pressure (Pabd) + detrusor pressure (Pdet)ssure (Pabd) + detrusor pressure (Pdet)

Patients may use mainly Pabd to void Patients may use mainly Pabd to void Pdet depends on intravesical volume Pdet depends on intravesical volume Pdet decreases at decreasing volume during voidinPdet decreases at decreasing volume during voidin

g phaseg phase Isovolumetric contraction (Piso) occurs when flow Isovolumetric contraction (Piso) occurs when flow

is suddenly interrupted (stop test)is suddenly interrupted (stop test)


Reduced Pdet at decreasing intravesical volume


Iso-volumetric Detrusor Contraction at Stop Test


Pressure Flow Relations

I: Isometric contraction of detrusorI: Isometric contraction of detrusor II: Detrusor pressure further increases activII: Detrusor pressure further increases activ

ation, flow continues to increase until maxiation, flow continues to increase until maximal activation of detrusor reachesmal activation of detrusor reaches

III: Decrease in bladder volume and decreasIII: Decrease in bladder volume and decreasing pressure and flowing pressure and flow


Relationship of Pressure & Flow


Passive Urethral Resistance Relation

Schafer proposed PURR, a straight line is drSchafer proposed PURR, a straight line is drawn through two values read from recordinawn through two values read from recording, the pressure at maximal flow rate and the g, the pressure at maximal flow rate and the lowest pressure at which actual flow occurs lowest pressure at which actual flow occurs (Pmuo)(Pmuo)

Griffiths used value of opening pressure (UGriffiths used value of opening pressure (URA) for passive urethral resistanceRA) for passive urethral resistance


The Abrams-Griffiths Plot


The Schafer Nomogram


The Contraction Power

WF is the power developed by detrusor contWF is the power developed by detrusor contraction per unit of arearaction per unit of area

During voiding, WF initially increases and rDuring voiding, WF initially increases and reaches a plateau value, then decreaseseaches a plateau value, then decreases

Classification of obstruction by obstructive Classification of obstruction by obstructive grades and contractilitygrades and contractility


Decrease in Contractile Velocity in Bladder Outlet Obstruction


Constrictive vs Compressive Pressure Flow Plots


Obstruction

Urethral resistance increases & flow decreasesUrethral resistance increases & flow decreases Residual urine increases as detrusor decompensatiResidual urine increases as detrusor decompensati

on occurson occurs Obstructive symptoms are unreliableObstructive symptoms are unreliable Bladder trabeculaion, thickened, impaired voiding Bladder trabeculaion, thickened, impaired voiding

may be aging, neuropathic, musculogenic, increasmay be aging, neuropathic, musculogenic, increased urethral resistance or in combinationed urethral resistance or in combination

Both filling and empty phases should be investigatBoth filling and empty phases should be investigated for voiding dysfunctioned for voiding dysfunction


Confirmation of Increased Urethral Resistance Measuring detrusor pressure at peak flowMeasuring detrusor pressure at peak flow Using A-G number by ICS nomogramUsing A-G number by ICS nomogram Urethral resistance R = Pdet / Qmax Urethral resistance R = Pdet / Qmax 22

Catheter of different size may interfere uretCatheter of different size may interfere urethral resistancehral resistance

Bladder dysfunction and increased urethral Bladder dysfunction and increased urethral resistance may coexistresistance may coexist


Pressure Flow Plot for Diagnosis of Obstruction


Abrams Griffiths Number

AG number = Pdet.Qmax – 2 x QmaxAG number = Pdet.Qmax – 2 x Qmax Obstruction Obstruction

AG> 40AG> 40 NonobstructionNonobstruction

AG<20AG<20 EquivocalEquivocal

20<AG<4020<AG<40


Constrictive Obstructionin Urethral Stricture A normal or high opening pressure and a coA normal or high opening pressure and a co

nstant flow rate although Pdet increases durinstant flow rate although Pdet increases during voidingng voiding

Bladder trabeculation and large residual uriBladder trabeculation and large residual urine may developne may develop


Constrictive Obstruction in Female Urethral Stricture


Constrictive Obstructionin Anterior Urethral Valve


Compressive Obstructionin BPH Obstruction


Compressive Obstructionin Dysfunctional Voiding


Constrictive Obstruction in Urethral Stricture


Obstruction in Detrusor External Sphincter Dyssynergia (DESD)


Bladder Outlet Obstruction in Women

No definite criteria for BOO in womenNo definite criteria for BOO in women A sustained voiding pressure and a low flow rA sustained voiding pressure and a low flow r

ate, moderate residual urine, and radiological ate, moderate residual urine, and radiological evidence of infravesical narrowing during voievidence of infravesical narrowing during voidingding

Primary bladder neck obstruction, urethral strPrimary bladder neck obstruction, urethral stricture, dysfunctional voiding, cystocele, post-icture, dysfunctional voiding, cystocele, post-incontinence stricture are most commonincontinence stricture are most common


Post-incontinence surgeryBladder neck obstruction


Spastic Urethral SphincterCompressive Obstruction


Decompensation of Detrusor

Acute urinary retention develops when intrAcute urinary retention develops when intra-urethral resistance increases combined wita-urethral resistance increases combined with an increase of sympathetic tone due to blah an increase of sympathetic tone due to bladder distensiondder distension

Relief of bladder distention may reverse acuRelief of bladder distention may reverse acute retention with the aid of alpha-blockerte retention with the aid of alpha-blocker

Decrease in detrusor tone may occur during Decrease in detrusor tone may occur during acute retentionacute retention


Low Contractility Force in BPH Obstruction


BPH with Acute Urinary Retention


Decompensation of Detrusor

Contractility is reduced as the length of smoContractility is reduced as the length of smooth muscle is beyond an optimal amountoth muscle is beyond an optimal amount

Increased upper tract pressure as intravesicaIncreased upper tract pressure as intravesical pressure is increased l pressure is increased

Reverse of detrusor contractility takes time Reverse of detrusor contractility takes time depending on the duration of detrusor decodepending on the duration of detrusor decompensationmpensation


Post-prostatectomy Low Detrusor Contractility


Chronic urinary retention

No detrusor contractilityNo detrusor contractility Patients use abdominal straining to voidPatients use abdominal straining to void Overflow incontinenceOverflow incontinence Small voiding amount Small voiding amount Resistance at ureterovesical junction is incrResistance at ureterovesical junction is incr

easedeased Upper tract dilatation and azotemiaUpper tract dilatation and azotemia


Poor bladder compliance and low contractility after prostatectomy


Detrusor Overactivity

No correlation of detrusor instability with seNo correlation of detrusor instability with severity of infravesical obstructionverity of infravesical obstruction

Aging processAging process Poor cortical perfusionPoor cortical perfusion Changes of vasoactive intestinal polypeptidChanges of vasoactive intestinal polypeptid

es or neurotransmitterses or neurotransmitters Occult neurological lesionOccult neurological lesion


Detrusor overactivity and Pseudodyssynergia in CVA


DESD with incontinence & Bilateral vesicoureteral reflux


Impaired Detrusor Contractility

Decrease in either contraction force or veloDecrease in either contraction force or velocity in about 40%city in about 40%

Wide spread degeneration of muscle cellsWide spread degeneration of muscle cells Degeneration of axonsDegeneration of axons Reduction of intermediate cell junctionsReduction of intermediate cell junctions Collagenosis between individual muscle celCollagenosis between individual muscle cel

ls with myohypertrophyls with myohypertrophy


Partial Bladder Outlet Obstruction and Energetics Decrease in glucose oxidation by 30%Decrease in glucose oxidation by 30% Decrease in creatine phosphate in rabbitDecrease in creatine phosphate in rabbit Less creatine phosphate and ATP in obstrucLess creatine phosphate and ATP in obstruc

ted bladder, which returned to normal after ted bladder, which returned to normal after relief of obstructionrelief of obstruction

Acute initial mitochondrial damage produceAcute initial mitochondrial damage produced by obstruction in rabbitd by obstruction in rabbit


Origins of Hesitancy

Time delay between start of voiding and effTime delay between start of voiding and effective flowective flow

Increased initial opening pressure related to Increased initial opening pressure related to compressive obstructioncompressive obstruction

Possibly due to delay in relaxation of externPossibly due to delay in relaxation of external sphincteral sphincter

No correlation with detrusor contractility No correlation with detrusor contractility


Poorly Relaxed Urethral Sphincter Hesitancy Intermittency


Origins of Frequency Urgency Urge incontinence Nocturia Attributed to detrusor instabilityAttributed to detrusor instability Correlated with small voided amount and laCorrelated with small voided amount and la

rge residual urinerge residual urine DI increases with age, decreased after prostDI increases with age, decreased after prost

atectomy,not correlated with detrusor pressatectomy,not correlated with detrusor pressureure

Not absolutely caused by obstructionNot absolutely caused by obstruction


Poor Stream & Dribblingin Obstruction Poor stream indicates either increased passiPoor stream indicates either increased passi

ve urethral resistance (BPO), decreased detrve urethral resistance (BPO), decreased detrusor contractility force, or in combination wusor contractility force, or in combination with active urethral resistance (spastic urethraith active urethral resistance (spastic urethral sphincter)l sphincter)

Terminal dribble may result from obstructioTerminal dribble may result from obstruction, evacuation of urine from urethra,or after-n, evacuation of urine from urethra,or after-contractioncontraction


Low detrusor contractility and Poor stream in woman


Post-micturition ContractionResidual urine sensation

Documents

排尿障礙治療中心 版權所有 Urodynamics and Bladder Outlet Obstruction Hann-Chorng Kuo Department of Urology Buddhist Tzu Chi General Hospital

排尿障礙治療中心版權所有 Urodynamics and Bladder Outlet Obstruction Hann-Chorng Kuo Department of Urology Buddhist Tzu Chi General Hospital