Dysfunctional Voiding in Children
Development of
Urethral Sphincter
Specific striated sphincter muscle closely applied to the smooth
muscle at membranous urethra and mid-urethra
A ring shape sphincter in early adolescence, which account for
initial high voiding pressure in infancy and early vesicoureteral
reflux
An omega shape shincter in adolescence after development of
urogenital septum
Congenital Abnormalities
Early detection and folic acid treatment markedly decrease spinal
defects
Upper and lower motor bladder dysfunction and pelvic floor
dysfunction may occur in thoracic or sacral lesions
Early prophylactic treatment of DESD by CIC, anticholinergics are
beneficial
Lipomeningocele
Difficult to identify by physical examination, MRI is the best
diagnostic method
Intradural lipoma results in disease and presentation
The most common urodynamic findings are consistent with an upper
motor neuron lesion
DESD is less common
Detrusor hyperreflexia and areflexia can be found in this group of
lesion
Sacral agenesis
Loss of the lower vetebral bodies by X-ray or MRI
Patients have stable neurological lesion
Patients may have no signs of denervation, hyperreflexia,
areflexia, intact sphincter, sphincter dyssynergia
Isolated tethered cord is less common
Severe bladder dysfunction and refractory incontinence may
occur
Surgical division of the filum may improve symptoms
Cerebral Palsy
Develops most commonly in premature infant
Infection and anoxia result in a non-progressive brain lesion and
muscular disability
Continence is often delayed to develop but intact
Uninhibited detrusor contractions without DESD is the most commonly
urodynamic finding
Pseudodyssynergia may occur
Bladder extrophy
Staged reconstruction by abdominal wall closure, epispadias repair,
bladder neck reconstruction and correction of VUR
Improved pelvic floor reconstruction after osteotomy has better
continence rate
Bladder augmentation may be indicated
Present with incontinence and recurrent UTI
Severe PUV may be detected antenatally, mild form is found in older
children
Bilateral hydroureter and hydronephrosis may develop in severe form
of valve disease
Transurethral ablation of valve resumes normal bladder but bladder
function depends
Anticholinergics, CIC and augmentation by ureter may be
indicated
Anorectal Malformations
Rare congenital lesions of cloaca
Associated with congenital GU abnormalities in 20% with low and 60%
high lesions,VUR, NVD, renal agenesis, renal dysplasia,
cryptorchidism
Urethrorectal fistula may develop at at high, intermediate or low
level
Neurogenic voiding dysfunction in 50%
Tethered cord is the main vertebral abnormality, which account for
NVD
Dysfunctional Voiding
A group of neurologically intact children presents with
incontinence, dysuria, large residual urine, recurrent UTI,
unilateral or bilateral hydronephrosis
Urodynamically classified into small capacity hypertonic bladder,
detrusor hyperreflexia, lazy bladder syndrome,non-neurogenic
neurogenic bladder
Treatment bases on interaction of bladder and external
sphincter
Occurrence of UTI and antibiotics
Bowel habit, fecal incontinence, and stool softeners
Catheterization schedule, urine amount
Medication and adverse effects
Sacral dimple, hair patch, lipoma
Enlarged bladder
Vincent curtsey
Urodynamic study
Infusion rate: 10% of capacity
Catheter: <6Fr intraurethral dual channel catheter, suprapubic
catheter is preferable for pressure flow study
Abdominal pressure by rectal catheter
Pelvic floor EMG – surface or needle
Measuring bladder compliance, detrusor pressure, and EMG activities
coordination
Type 1: Onset of EMG activity with initiation of voiding
Type 2: intermittent inappropriate external sphincter contraction
during voiding,which causes a reflex inhibition of detrusor
contraction
Type 3: Persistent increased EMG activity during filling and
voiding phases, which causes large residual urine and
incontinence
Pseudodyssynergia: presence of urodynamic DESD in neurologically
intact patient
Leak-point pressures
Detrusor leak-point pressure (DLPP): The detrusor pressure causing
urinary leakage per urethrum in the absence of detrusor
contractions
A DLPP of more than 40 cm water has a risk of upper tract
deterioration
Valsalvar LPP (VLPP): Assessing urethral resistance by abdominal
straining, a VLPP <60 cm water indicates intrinsic sphincter
deficiency
Spinal dysraphisms
Sacral agenesis
Imperforated anus
Diurnal enuresis
Dysfunctional voiding
Uroflowmetry with surface EMG
Pressure flow study recording Pves,Pabd, Pdet, EMG activity, and
uroflowmetry
Videourodynamic study by suprapubic catheter or intra-urethral
catheter
Dysfunctional Voiding
Increased voiding pressure during voiding with contraction of the
urethral sphincter
Dysfunctional bowel evacuation and constipation
Treatment directed at urodynamic abnormalities reduce the incidence
of breakthrough UTI and increase resolution of vesicoureteral
reflux
Pelvic laxity
Inappropriate stimulation of guarding reflex results in inhibition
of detrusor contraction
Elevated postvoid residual urine
Host resistance – ability of bladder to wash out pathogens
Well hydration, void with strong stream, and complete voiding are
important in prevention of UTI
Treatment aims at relaxation of the pelvic floor rather than the
bladder
The severest form of dysfunctional voiding
Symptom complex including nocturnal enuresis, diurnal enuresis,
constipation, encopresis, UTI, and upper tract dilatation
Uninhibited detrusor contractions and dyssynergic external
sphincter
Voiding retraining
Play a major role in etiology of congenital VUR
Important in development of VUR in older child without congenital
VUR
Responsible for reflux exacerbation and renal scarring
Therapy to VUR should aim at correction of dysfunctional
voiding
Urodynamic studies in infants
High voiding pressures (160cm water) with low bladder capacity in
infant with gross dilating reflux
Voiding pressure in infant without reflux is 80 cm water
By age 2 years, voiding pressure diminished (70 cm water) and
capacity increased, but unstable detrusor remain
Boys with high grade reflux have dilated posterior urethra
Higher voiding pressure is seen in children with grades IV and V
reflux
Normalization of voiding pressures explains high rate of reflux
resolution in childhood
Up to 60% of children with reflux have urodynamic abnormality
Detrusor overactivity and sphincter dyscoordination
Primary sphincter overactivity is more associated with high grade
reflux and renal scarring
Bladder instability improves over time
Poor cooperation of patient
Appropriate size of intra-urethral catheter – 3 Fr, 5 Fr, 7
Fr?
Frequent increased abdominal pressure
Treatment of detrusor overactivity with anticholinergics improves
resolution or improvement in VUR than stable bladders
A higher surgery rate in stable bladder with VUR
Controversy remains in correlation of urodynamic abnormalities with
grades of VUR and anticholinergic treatment with resolution rate of
VUR
Resolution of VUR and improved DI after anticholinergic and CIC in
myelomeningocele
Associated with an increased risk of urinary tract infection
With or without reflux
Incontinent day and night with fecal soiling
Observed to engage in holding maneuver to avoid urination and
defecation
Most often occur in girls
Recurrent cystitis due to short urethra and bladder
colonization
Congenital VUR or secondary VUR due to these aberrant toilet
training habits
Breakthrough UTI and Dysfunctional voiding
Girls with history of voiding dysfunction have higher rates of
breakthrough UTI (4 times more common in DES)
Unsuccessful surgical outcome was seen in children with DES
Adequate hydration, timed voiding, stool softeners, laxatives, as
well as anticholinergics may be helpful
Children with mono-symptomatic enuresis have a very low urodynamic
abnormality
VUR has been found in child with frequency urgency and urinary
incontinence without history of UTI
15% of children had positive urodynamic findings and 16% had renal
scarring
Adequate hydration and timed voiding
Stool softeners and laxatives
Intermittent catheterization
Improved bladder compliance and DI after ditropan therapy in
myelomeningocele
Adequate hydration
Provide adequate urine production and wash out effect of
bladder
Prevent constipation and reduce colonization of pathogen in
perineum
Reduce detrusor instability through dilution of urine and decrease
urine permeability into urothelium
Time voiding is required
Oxybutynin – effective in reducing detrusor overactivity, side
effects of mucosal dryness & constipation
Ditropan XL – elimination of peak drug effect and reduce adverse
effects
Tolterodine – M3 anticholinergic
Phenylpropanolamine, pseudoephedrine – in ISD with incontinence
ready for CIC
Regular pelvic floor muscle exercises provide adequate relaxation
of pelvic floor including urethral sphincter
A synergistic voiding pattern can be achieved after
rehabilitation
Combined with fluid and anticholinergic therapy
Biofeedback for
Success relies on motivation of children Uroflow- surface EMG
integrated biofeedback
Cystometry biofeedback to inhibit detrusor overactivity in patients
with DI
Visual or audio biofeedback may be more successful than verbal
biofeedback
New technique in reducing urethral resistance by paralyzing
striated urethral sphincter
Intra-detrusor injection to reduce detrusor overactivity and
increase bladder capacity
Restoration of normal voiding pattern
Repeat injection may be necessary