Diagnostic Evaluation of Lower Urinary Tract Dysfunction Victor W. Nitti, MD Professor and Vice Chairman Department of Urology NYU School of Medicine
Lower Urinary Tract Function Storage of urine at low pressure to protect kidneys and assure continence Voluntary evacuation of urine
Lower Urinary Tract Function Can be viewed anatomically Bladder Outlet Can be viewed functionally Storage Voiding
Functional Classification of Voiding Dysfunction Problem with emptying Problem with storage Either of the above may be due to Bladder dysfunction Bladder outlet or urethral dysfunction *Wein, 1982
Lower Urinary Tract Symptoms Storage Symptoms Frequency Urgency Incontinence Stress Nocturia “Pain” Emptying Symptoms Slow stream Need to strain Hesitancy Intermittency Feeling of incomplete emptying
Other Sequelae of LUT Dysfunction Urinary retention Recurrent UTI’s Hydronephrosis Renal insufficiency
Evaluation of Lower Urinary Tract Dysfunction History Physical Ancillary tests Urine Analysis PVR Uroflow * Diaries * Pad test * Urodynamics Radiography Cystoscopy Videourodynamics
History Symptoms Characterization Duration Severity Response to treatments or other factors Effect of activities and QoL Can use symptom scores
History Voiding Habits Fluid Intake Bowel habits Sleeping pattern Hematuria UTI’s Vaginal symptoms
History Urologic Ob/Gyn Neurologic Medical / surgical Social / psych Radiation Pelvic trauma Medications
Physical Exam Abdominal exam Pelvic Exam Muscular integrity vaginal mucosa atrophy prolapse assess 3 levels presence/grade Muscular integrity assess ability to squeeze assess strength of squeeze Provocative stress test
Evaluation - Physical Rectal Exam Neurologic assessment Tone Posterior compartment prolapse Rectal masses Anal sphincter integrity Neurologic assessment Overall coordination MMS Sensation Reflexes
Urine Analysis UTI Hematuria Specific Gravity Proteinuria Glucosuria
Voiding and Intake Diaries Very useful tool to evaluate LUTS Correlate history with reality Number of voids, incontinence episodes, urgency and severity, nocturia Assess fluid intake and urine output Determine Avg. voided volume Max. voided volume Nocturnal vs. daytime urine production Nocturnal polyuria
Voiding and Intake Diary (Frequency/Volume Chart) Time Intake (cc) Output (cc) Comment Urgency? Incontinence Stress/Urgency
Pad Test Use when it is important to quantify the amount of urine loss Can be done under specific conditions, i.e. stress pad test, or to mimic typical day Stress pad test 20 minute 1 hour 24 hour
Post Void Residual Excellent assessment of emptying Ultrasound (bladder scan) or catheterization Results may prompt further investigation
Uroflow Uroflowmetry with the measurement of PVR urine is recommended as a screening test for symptoms suggestive of urinary voiding dysfunction ($th ICI, 2008) * Voiding symptoms Elevated PVR Results may prompt further investigation Consider shape on curve not only Qmax, Qavg, etc.
Abdominal straining pattern Normal Uroflow Flattened or obstructed pattern Interrupted Pattern
Cystoscopy LUT endoscopy highly recommended (4th ICI) When initial testing suggest other pathologies, e.g. hematuria When pain or discomfort features in the patient’s LUTS : these may suggest an intravesical lesion When appropriate in the evaluation of vesicovaginal fistula and extra-urethral urinary incontinence
Imaging Upper Urinary Tract Lower Urinary Tract Pelvis Renal Ultrasound CT scan MRI Lower Urinary Tract Cystography Pelvis Ultrasound Transvaginal Abdominal CT scan MRI
Imaging Imaging of the upper urinary tract is highly recommended in specific situations (4th ICI, 2008) Hematuria Neurogenic urinary incontinence e.g. myelodysplasia, spinal cord trauma, Incontinence associated with significant post-void residual Co-existing loin/kidney pain Severe pelvic organ prolapse, not being treated Suspected extra-urethral urinary incontinence Urodynamic studies which show evidence of poor bladder compliance
Role of Urodynamics Level 1 evidenced-based “indications” for its use are surprising lacking Difficult to conduct RCTs For conditions where lesser levels of evidence and expert opinion strongly suggest clinical utility Were “empiric treatment” is potentially harmful or even life-threatening (e.g. neurogenic voiding dysfunction) Symptoms can be caused by a number of different conditions and it is difficult to study pure or homogeneous patient populations
Role of Urodynamics Given the current state of evidence for UDS studies, what is most important is that the clinician has clear cut reasons for performing the study and that the information obtained will be used to guide treatment of the patient Therefore it is more useful to describe the role of UDS in clinical practice rather than precise “indications” for its use
Practical Use Of Urodynamics UDS is most useful when history, physical exam and simple tests are not sufficient to make an accurate diagnosis and/or institute treatment
Practical Use Of Urodynamics Clinical applicability in two general scenarios: To obtain information needed to make an accurate diagnosis for what condition(s) is causing symptoms (e.g. lower urinary tract symptoms or incontinence) To determine the impact of a disease that has the potential to cause serious and irreversible damage to the upper and lower urinary tract, sometime without symptoms Neurological diseases, radiation cystitis
Role of UDS in Clinical Practice 4th ICI, 2008 To identify or rule out factors contributing to lower urinary tract dysfunction (e.g. urinary incontinence) and assess their relative importance To obtain information about other aspects of lower urinary tract function or dysfunction To predict the consequences of lower urinary tract dysfunction on the upper urinary tract Hosker G, et al : Dynamic Testing. In: Incontinence 4th International Consultation on Incontinence. United Kingdom, Health Publications, 2009, pp. 413-552.
Role of UDS in Clinical Practice 4th ICI, 2008 To predict the outcome, including undesirable side effects, of a contemplated treatment To confirm the effects of intervention or understand the mode of action of a particular type of treatment (especially a new one) To understand the reasons for failure of previous treatments for symptoms (e.g. urinary incontinence) or for lower urinary tract function in general. Hosker G, et al : Dynamic Testing. In: Incontinence 4th International Consultation on Incontinence. United Kingdom, Health Publications, 2009, pp. 413-552.
Urodynamics Preparation Decide on questions to be answered before starting the study Design the study to answer these questions Customize the study as necessary
Urodynamics Guidelines A study not duplicating symptoms when an abnormality is recorded is not diagnostic Failure to record an abnormality does not rule out its existence Not all abnormalities are clinically significant
Urodynamics Phases of Micturition Cycle Storage or filling phase Cystometrogram (CMG) Provocative maneuvers ALPP Urethral pressure measurements Emptying Voiding pressure - flow study Urethral sphincter or pelvic floor electromyography (EMG) Post void residual
Cystometry CMG is measurement of the bladder’s response to filling Filling pressure Sensation Involuntary contractions Compliance Capacity Control over micturition
Idealized Normal Adult CMG Filling and Storage Voiding Pressure Volume
Cystometry CMG only assesses the bladder’s response to filling Many abnormalities of filling and storage are caused by abnormalities of voiding If CMG alone is done, underlying problem maybe missed
CMG Multichannel Urodynamics
Multichannel Urodynamics Bladder pressure monitoring (Pves) Abdominal pressure monitoring (Pabd) Subtracted detrusor pressure (Pdet) Urethral pressure monitoring* EMG Voiding pressure / flow study - Contractility - Pressure - flow relationship (obstruction) - Emptying
Urodynamic Parameters Filling and Storage Sensation and capacity Involuntary detrusor contractions Idiopathic detrusor overactivity Neurogenic detrusor overactivity May be spontaneous or provoked
Involuntary Detrusor Contractions
Urodynamic Parameters Filling and Storage compliance ml/cm H20 Absolute pressure probably more important than a compliance number or value Storage pressures > 40 cm H2O known to be harmful (McGuire, et al, 1981) Impaired compliance usually a result of outlet obstruction (anatomical or functional) or structural changes like radiation cystitis or TB
Impaired Compliance
Impaired Compliance + IDC
A Problem With Compliance: These two are not the same cmH2O cmH2O 50 5 400 40 mL mL Compliance = 8 ml/cmH2O Compliance = 8 ml/cmH2O
Impaired Compliance & IDC’s 40 ml. 280 ml. 330 ml. 400 ml. Impaired Compliance & IDC’s Pves = 40 cm H20 80 ml. 160 ml.
Urodynamic Parameters Storage Leak point pressures Abdominal or Valsalva (ALPP) Bladder or detrusor (BLPP) Urethral pressure profile MUP MUCP
Abdominal Leak Point Pressure Abdominal pressure required to cause urinary incontinence in the absence of a detrusor contraction (AKA Valsalva LPP) Measure of intrinsic sphincter function Ability of bladder outlet to resist changes in abdominal pressure Used to evaluate stress incontinence Normal intrinsic sphincter function No leak at any physiologic Pabd No “normal ALPP”
Leakage at arrow = ALPP = 109cmH2O
Detrusor Leak Point Pressure Detrusor pressure required to cause urinary incontinence in the absence of an increase in abdominal pressure (AKA Detrusor LPP) Impaired compliance Involuntary contractions Bladder’s response to increased outlet resistance DESD Other causes of bladder outlet obstruction
Leakage at arrow = BLPP = 45 cmH2O
Detrusor Leak Point Pressure DLPP > 40 cm H2O is potentially dangerous to the upper tracts!
Urodynamic Parameters Emptying Obstruction or impaired contractility Detrusor contractility Sphincter coordination Bladder neck / internal sphincter Striated sphincter DESD Dysfunctional voiding
Neurophysiology of Micturition Normal voiding accomplished by activation of micturition reflex Relaxation of striated urethral sphincter Contraction of detrusor Opening of vesical neck and urethra Onset of urine flow Coordination between pontine and sacral micturition centers needed Suprapontine input allows for voluntary control of the micturition reflex
Sphincter Coordination DESD Can only happen with neurological disease Suprasacral spinal cord “Pseudodyssynergia” No neurological disease, a learned behavior Dysfunctional voiding Hinman syndrome Non-neurogenic neurogenic bladder Learned voiding dysfunction
DESD Fill rate = 50 ml/min Fill rate = 25 ml/min
Urodynamics and Incontinence
Urodynamics For Incontinence When evaluating an incontinent patient determine what happens when the patient leaks Demonstrate incontinence on the study! Is the problem the bladder or the outlet or both?
Urodynamics: Stress Incontinence Uncertain diagnosis Mixed (urge and stress) symptoms Failed conservative treatment History of previous surgery Prior to surgical treatment of incontinence
Urodynamics: Stress Incontinence Prior to surgical treatment of incontinence Documentation of stress incontinence if not seen on physical exam Uncover occult instability or determine degree of instability in a patient with mixed incontinence Prognostic value Determination of ALPP or MUCP May change surgical approach Detrusor contractility and voiding habits
UDS in Female SUI: Literature- Based Practical Tips For women with pure SUI without urge symptoms who empty normally and demonstrate SUI on physical exam, UDS will not provide much useful information. For women with SUI who are considering surgical correction who have mixed symptoms or emptying difficulties UDS probably has its most significant role
UDS in Female SUI: Literature-Based Practical Tips Urethral function measurements of leak point pressures and urethral closure pressures should not used as a single factor to grade the severity of incontinence Use caution with the prediction of the outcome of any surgical treatment on the basis of contemporary urethral function tests 4th ICI Committee on Dynamic Testing 2009
Pathophysiology of SUI ISD ONLY Urethral Hypermobility Urethral Hypermobility + ISD All women with SUI have some degree of ISD because hypermobility often exists without SUI
What Is ISD? Portion or component of stress incontinence not caused by a support defect (urethral hypermobility) Lack of coaptation Deficiency of urethral musculature Deficiency of submucosal layer Neurological injury
Urodynamic Stress Incontinence with hypermobility and ALPP = 109 cmH2O How much ISD?
ALPP and ISD Where Do The Numbers Come From? MUCP and ALPP measured in 125 women with SUI ALPP < 60 cmH2O All had high grade (3) incontinence (81% continuous leakage) 75% fixed urethra ALPP 60-89 cmH2O 80% pronounced type II urethral hypermobility and grade 2-3 incontinence ALPP > 90 cmH2O Lesser grades of incontinence and minimal to gross hypermobility (type I or II) ALPP unrelated to MUCP McGuire, et al J Urol 1993; 150:1452-1455
The Inference ALPP < 60 cmH2O = ISD ALPP 60 - 90 cmH2O = equivocal, a component of ISD ALPP > 90-100 cmH2O little or no ISD But if no hypermobility, SUI must be caused by ISD Current technology does not permit a method to distinguish between ISD and hypermobility
“Type 3 SUI” Gravitational Incontinence ALPP = 34 cmH2O Open bladder neck Type 3 SUI
Urethral Hypermobility vs. ISD Fleischmann et al J Urol 169:999, 2003 No correlation of ALPP with hypermobility: ALPP < 60 24% hypermobile ALPP 60-90 31% hypermobile ALPP > 90 41% hypermobile No correlation of hypermobility or ALPP with number of incontinence episodes or pad weight ISD and hypermobility can coexist but do not define discrete classes of patients Use parameters to characterize not classify
Urethral Pressure Measurements UPP – intraluminal pressure along length of urethra Maximal urethral pressure (MUP) Maximum pressure of the measured profile Maximum urethral closure pressure (MUCP) Maximum difference between the urethral and intravesical pressures Functional profile length Length of the urethra along which the urethral pressure exceeds the intravesical pressure in women Urethral pressure profile
Urethral Pressure Profiles Stress UPP - female UPP- male
Stress Induced Detrusor Overactivity Involuntary detrusor contraction preceded by an increase in abdominal pressure Often occurs in conjunction with genuine stress incontinence AKA stress hyperreflexia Patients often complain of “stress incontinence” but usually with high volume loss of urine May respond to anticholinergics, but may also respond to treating stress incontinence
Stress Induced Detrusor Overactivity SIDO SIDO DO DO DO Pdet Pves Pabd
Urodynamics: Urge Incontinence Failed empiric treatment Especially in the elderly Young women Occult neurological disease Associated neurological disease Known condition that causes voiding dysfunction Elevated PVR Abnormal uroflow Prior to invasive treatments Augmentation cystoplasty Neuromodulation
Evaluation of Voiding Phase in Women With LUTS Carlson et al J Urol 164:1614, 2000 Abnormality of voiding phase - 44 (33%) Normal voiding - 58 (43%) Unable to void - 32(24%) Mean age of women with abnormalities of voiding slightly lower 47.5 vs. 55.7 (p=0.022)
Voiding Phase Abnormalities Dysfunctional voiding 16 Obstruction from moderate cystocele 6 Primary vesical neck obstruction 6 DESD (initial presentation of neurological disease) 5 Obstruction after incontinence surgery 3 Obstructing urethral stricture 3 Impaired contractility 2 After contraction mimicking symptoms 2 Obstructing urethral diverticulum 1
Dysfunctional Voiding
37 year old woman in unable to void 1 year prior to presentation, found to have a distended bladder – asymptomatic retention On CIC 3-4 x/day, no spontaneous voiding No neurological history or sx No chronic medical problems G0P0 Physical exam unremarkable Renal ultrasound WNL BUN and creatinine WNL Cystoscopy and bladder bx’s normal
Videourodynamics IDC Void Void
Uroflow 5 months after BN Incision PVR = 16 ml
Outcome 3.5 years post TUI-BN Voiding spontaneously No CIC No significant LUTS Rare SUI with sneeze (not bothersome) Qmax = 38.5 ml/s Voided volume = 459 ml PVR = 50 ml.
LUTS In Young Women Rosenblum et al, Int Urogynecol J, 2004;15:373-377 Current practice is to avoid UDS in young women with primary complaint of frequency and urgency unless: UUI Elevated PVR Abnormal uroflow Failure to respond to tx
ME – 18 Year Old Female Also c/o frequency/urgency and daytime urge incontinence No other significant medical history PE unremarkable PVR minimal
ME – 18 Year Old Female Chief complaint nocturnal enuresis Refractory to DDAVP and Imipramine First episode at age 5 Intermittent throughout life Currently wetting at least once/night
ME - Urodynamic Evaluation Urge inc Void 80 ml 110 ml 50 ml/min 25 ml/min
Voiding
ME – 18 Year Old Female Based on urodynamics MRI on spine ordered Lipoma with tethered cord Diagnosis – detrusor hyperreflexia with DESD
Urodynamics in Pelvic Prolapse Can be useful to determine cause of symptoms Storage and voiding symptoms Stress incontinence Preoperative evaluation Occult stress incontinence Capacity Compliance
Rest Void
Rest Void Cystocele reduced with pessary
No pessary Pessary
Radiation Cystitis 120 ml instilled Start Void