Abdominal wall electromyography: a noninvasive technique to improve pediatric urodynamic accuracy

Animated biofeedback yields more rapid results than nonanimated biofeedback in the treatment of dysfunctional voiding in girls

PURPOSE

Biofeedback is known to effect symptomatic and objective cure in children with dysfunctional voiding. While some authors advocate animation assisted biofeedback to achieve success, we previously demonstrated similar success without animation. We recently used animated biofeedback aimed at simplifying muscle isolation and encouraging patient interest. We compared the efficacy of biofeedback with and without animation in treating dysfunctional voiding, and its concomitant urinary symptoms.

MATERIALS AND METHODS

We compared our experience with the last 60 cases of biofeedback using electromyography tracing alone (nonanimated) with our first 60 cases using the Urostym Pediflow program (animated). All 120 girls presented with urinary complaints and exhibited dysfunctional voiding on electromyography uroflow. Post-void residual measurements were made by ultrasound. We compared the 2 groups with respect to time to resolution of symptoms and dysfunctional voiding, and improvement in post-void residual volume after treatment.

RESULTS

The nonanimated and animated groups were comprised of girls of similar ages (7.3 years vs 6.9 years). There was no significant difference between the 2 groups regarding symptom relief at a mean of 5.4 months after therapy, including daytime incontinence, nocturnal enuresis, urgency, frequency and hoarding. Three patients in each group experienced urinary tract infection following treatment, compared to 42 and 41 before treatment in the nonanimated and animated groups, respectively. Dysfunctional voiding resolved in 95% of patients in both groups. Post-void residual reduction was similar, namely from 35% to 9% of pre-void volume in the nonanimated group, and from 28% to 8% in the animated group. Children in the animated biofeedback group achieved success in significantly fewer sessions (3.6) than those undergoing nonanimated biofeedback (7.6, t test p <0.05).

CONCLUSIONS

Despite our proved experience with nonanimated biofeedback systems and our inexperience with an animated system, animated biofeedback systems yielded similar results in a significantly shorter time. Animated and nonanimated biofeedback is efficacious in the treatment of dysfunctional voiding and its symptoms.

ABILITY OF A NORMAL DYSFUNCTIONAL VOIDING SYMPTOM SCORE TO PREDICT UROFLOWMETRY AND EXTERNAL URINARY SPHINCTER ELECTROMYOGRAPHY PATTERNS IN CHILDREN

PURPOSE

We correlated uroflowmetry/electromyography (EMG) patterns and post-void residual urine volume (PVR) in children with a normal dysfunctional voiding symptom score (DVSS) and determined whether a normal DVSS can predict uroflowmetry/EMG/PVR results.

MATERIALS AND METHODS

We prospectively studied 51 children with a normal DVSS, and negative neurological and urological history who underwent uroflowmetry/EMG and PVR measurements. Statistical results were correlated with patient age and gender using Cohen's kappa and Fisher's exact test.

RESULTS

All children had a normal DVSS for gender and 37 (73%) had bell-shaped uroflowmetry curves. Eight of the 14 children with nonbell-shaped uroflowmetry curves had plateaued and 6 had fractionated curves. Five boys and 13 girls (35%) had decreased EMG patterns, 7 boys and 8 girls (29%) had increased patterns and 5 boys and 13 girls (35%) had variable patterns (Cohen's kappa score 0.11). Of the 37 children (65%) with bell-shaped uroflowmetry curves 24 had normal PVR, while 13 of 37 (35%) had elevated PVR. Eight of the 14 children (57%) with nonbell-shaped uroflowmetry curves had normal PVR and 6 (43%) had elevated PVR (Cohen's kappa score 0.13). Seven of 37 children (19%) with bell-shaped uroflowmetry curves and 7 of 14 (50%) with nonbell-shaped uroflowmetry curves had a significantly distended bladder (p = 0.04). Nine of the 14 children (64%) with a significantly distended bladder had abnormal PVR. Ten of the 37 children (27%) without a significantly distended bladder had abnormal PVR (p = 0.02).

CONCLUSIONS

Normal DVSS for gender is able to predict a bell-shaped uroflowmetry curve in most children, while EMG patterns and PVR do not correlate with uroflowmetry curves in these children. Children with a significantly distended bladder frequently have nonbell-shaped uroflowmetry curves as well as elevated PVR.

Cystometry in infants and children with no apparent voiding symptoms

OBJECTIVE

To evaluate bladder function in infants and children with no apparent voiding symptoms.

SUBJECTS AND METHODS

The study included 83 infants and children (51 boys and 32 girls, aged 3 days to 12 years) with no neurological and lower urinary tract pathology but who had undergone or were about to undergo surgery for upper urinary tract or other pathology. They were evaluated using slow-filling cystometry, with simultaneous electromyography recorded using surface electrodes on the perineum. The voiding variables were compared among groups categorized by age, sex and body weight.

RESULTS

In boys and girls, respectively, the mean (SD) post-void residual urine volume (PVR) was 6.3 (3.9) and 5.4 (4.8) mL, the maximum detrusor pressure during voiding was 66.1 (13.1) and 56.6 (14.7) cmH2O and the maximum voiding pressure was 73.9 (16.6) and 62.7 (16.2) cmH2O. There was no significant difference in these variables between the sexes or between infants and children (P > 0.05). Detrusor instability (DI) was apparent in nine of 83 (10.8%) infants and children and occurred in the late filling phase. Bladder capacity increased with age and body weight (from 30 mL in neonates to 350 mL in 12-year-old children), and mean (SD) bladder compliance increased with age, from 3.6 (0.5) mL/cmH2O in infants to 13.3 (3.0) mL/cmH2O in older children, at a filling rate of 5-7 mL/min.

CONCLUSIONS

In these infants and children with no apparent voiding symptoms, most bladders were stable, DI could occur in the late filling phase of cystometry, voiding was nearly complete, the PVR being usually < 10 mL, and bladder capacity increased with age and body weight.

Diagnosis and treatment for children who cannot control urination

Primary NE is probably a condition rooted in biologic problems. There is a strong hereditary component. Altered nervous system function may lead to disorganization of how bladder function is controlled and how vasopressin is released. In extreme cases, this disorganization may also be reflected in psychologic issues, such as attention-deficit disorder. Primary NE should not be viewed as laziness of the child, but as an obstacle the child needs professional help to hurdle. The practitioner should collaborate with a pediatrician, urologist, and psychologist in managing children who wet. Routine office evaluation should exclude incontinence as a cause of wetting. When a screening ultrasonogram is normal, this helps the practitioner determine that striking birth defects are unlikely. Follow-up of management by interview with interested staff is necessary. Wetting is reliably correctable and probably best addressed by combination treatment structured as an ETP. Specific treatments vary according to personal preferences. The treatment with strongest scientific research, desmopressin, may be the least effective for cure. The most effective treatment for cure, alarm with behavior reinforcement, is the least often prescribed. A miscellany of adjunctive treatments should be suggested when there are abnormalities in functional bladder capacity, defecation, urethritis, vulvitis, diet sensitivity, upper-airway obstruction, and other areas.

Uroflowmetry combined with simultaneous measurement of abdominal pressure by tocodynamometer

We used a guard-ring tocodynamometer to detect abdominal straining simultaneously with uroflowmetry in 19 normal volunteers, 63 patients with benign prostatic hyperplasia and 25 with a neurogenic bladder. The pressure curves obtained by the tocodynamometer were similar to the intrarectal pressure curves simultaneously measured by an intrarectal balloon. The frequency of straining in patients with benign prostatic hyperplasia did not differ significantly from that in normal volunteers and did not decrease postoperatively. In these patients abdominal straining did not produce a synchronously increased flow rate. Patients with a neurogenic bladder frequently voided with straining. Abdominal straining tended to produce a synchronously increased flow rate in patients with lesions in the sacral cord or peripheral nerves but not in patients with neural lesions above the sacral cord. The presence of urinary flow without straining was considered to signify an intact voiding reflex. We believe that this method is simple and provides much more information than uroflowmetry alone to evaluate voiding dysfunctions.

The importance of leg support for relaxation of the pelvic floor muscles. A surface electromyograph study in healthy girls

The ability of relaxation is a necessary component for a good function of the pelvic floor muscles (PF). The importance of a relaxation technique for the PF has not been paid much attention in children either in urological examinations or treatments. The aim was to seek postures with optimal relaxation of the PF for use in clinical practice with girls. The relaxation of the PF and adjacent hip and abdominal muscle groups was studied by using surface electromyography (EMG) and a polygraph writer in 20 healthy volunteer girls, 6 and 10 years of age. They were placed in three different postures with their legs supported and unsupported. In postures with supported legs, the relaxation was observed in 94% recorded from the PF and in 97% from the adjacent muscles. EMG amplitudes from the PF and adductor muscles were significantly higher in postures with unsupported legs compared to postures with supported legs (p less than 0.05). The present study indicates that the optimal relaxation of the PF can be achieved by adequate leg support. This can be important to apply particularly in clinical situations such as urodynamic investigations, in uro-biofeedback training and for the design of pelvic floor exercises for girls.

Urethral valves--treatment, results and urodynamic assessment

Posterior urethral valves is an uncommon condition, but it poses many diagnostic and therapeutic problems. Long term follow up of these patients revealed that the majority of these boys have long term problems. In depth assessment of 10 boys with this problem revealed that their upper urinary tracts remained stable whereas urodynamic studies showed gross micturition abnormalities. Most methods of assessing the urinary tracts in these boys are invasive (eg. Intravenous urography, micturating cystography) and may indeed show no change in upper tract radiology despite marked abnormalities of micturition detected by urodynamics and which may require further investigation and treatment. We therefore recommend regular urodynamic assessment of these boys as it is accurate and initially non-invasive. Those boys with a detectable abnormality can progress to further studies.

Urodynamic abnormalities in neurologically normal children with micturition dysfunction

We evaluated by video urodynamic study 60 children between 4 and 16 years old who had presented with various combinations of urinary frequency, diurnal incontinence, enuresis, voiding symptoms, recurrent urinary infections and upper tract changes. A number of seemingly distinct categories of detrusor dysfunction could be identified, which may have a bearing on logical treatment selection. In addition, abnormalities of sphincter activity were noted in 12 children. The limitations and interpretation difficulties of urodynamic studies in children are stressed.

The uninhibited bladder in children: effect of treatment on recurrence of urinary infection and on vesicoureteral reflux resolution

We studied and treated prospectively 62 neurologically normal children with vesicoureteral reflux using urodynamic techniques to identify uninhibited bladder contractions with voluntary sphincteric obstruction (dyssynergia). All children received antibiotic prophylaxis. Anticholinergic drugs were used additionally to treat uninhibited bladder contractions. During 6 years of followup treatment of uninhibited contractions produced a 4-fold reduction in the incidence of recurrent urinary infection and tripled the rate of reflux resolution compared to controls. These data suggest that uninhibited contractions with voluntary sphincter obstruction are an important prognostic finding in children with reflux, which when treated successfully can alter the disease course and may make surgical therapy of reflux unnecessary for some.

Supplementation of cystometrography with simultaneous perineal floor and rectus abdominis electromyography

A total of 26 patients with symptomatic voiding dysfunction underwent cystometrography concomitant with simultaneous perineal floor and rectus abdominis electromyography. Of the patients 20 had well defined neurological pathological conditions. Cystometrography/perineal electromyography revealed detrusor hyperreflexia with appropriate sphincter relaxation in 8 patients, with vesicosphincter dyssynergia in 10 and with pseudo-dyssynergia in 2. Rectus electromyography in these patients did not reveal electromyographic activity during the filling and expulsion phases of the cystometrogram. However, the 6 neurologically normal patients were noted to have detrusor areflexia with nonrelaxation of the sphincter on urodynamic examination. These patients characteristically attempted to void by abdominal straining, resulting in a concomitant increase in rectus and perineal electromyography activity. We conclude that the addition of rectus electromyography to the standard urodynamic methodology can improve significantly the recognition of intravesical pressure elevation owing to voluntary contraction of the abdominal musculature.

Neurologic disease masquerading as genitourinary abnormality--the role of urodynamics in diagnosis

While the great majority of patients with neurogenic bladder and sphincter dysfunction have identifiable neurologic disease a small group will present with obvious genitourinary problems caused by not so obvious neurologic conditions. Thirteen such patients are presented, with a discussion of the ability of various urodynamic tests to predict the presence of significant neurologic disease.

The vesical sphincter electromyogram in children with normal and abnormal voiding patterns

Recording the vesical sphincter electromyogram clarifies abnormal patterns of voiding in children. Since the electromyogram patterns in children with normal voiding patterns have not yet been evaluated, we recorded the sphincter electromyograms during voiding of 39 children with normal voiding patterns. These normal electromyograms were compared to those recorded in 86 children with abnormal voiding patterns. Each of the 39 children with a normal voiding pattern demonstrated synergy of the vesical sphincter during voiding. Of the 86 children with an abnormal voiding pattern 69 per cent demonstrated synergy and 31 per cent demonstrated dyssynergia of the vesical sphincter during voiding. Of the children with dyssynergia 89 per cent were girls and only 11 per cent were boys. Sphincter dyssynergia was demonstrated only by children with an abnormal pattern of voiding and those with a history of a normal pattern of voiding demonstrated only sphincter synergy (p less than 0.005). The electromyographic diagnoses of vesical sphincter synergy and dyssynergia obtained by surface electrode recordings correlated with the clinical voiding patterns of the children.