The efficacy of physiotherapeutic intervention with biofeedback assisted pelvic floor muscle training in children with dysfunctional voiding

Open AccessPublished:September 24, 2021DOI:https://doi.org/10.1016/j.jpurol.2021.09.022

      Summary

      Introduction

      Dysfunctional voiding (DV) in children is a common issue, which can be found in up to 30% of children with wetting problems. Biofeedback assisted pelvic floor muscle training (PFMT) is an established nonpharmacological method to treat DV. The aim of the present study was to evaluate the efficacy of physiotherapeutic intervention with biofeedback assisted PFMT in children with DV.

      Study design

      Children referred with DV, unresponsive to standard urotherapy were included in this study. All children underwent biofeedback assisted PFMT sessions with a physiotherapist. Uroflowmetries and measurements of post-void residual (PVR) urine were performed before and after the treatment, and the following parameters were registered; daytime incontinence (DI), nocturnal enuresis (NE), constipation, faecal incontinence (FI), and recurrent urinary tract infections (UTI). Other concomitant treatments were noted. The primary outcomes were the resolution of DV evaluated by uroflow curve configuration and PVR. Secondary outcomes were the resolution of DI, NE and the reduction of recurrent UTIs.

      Results

      Forty-six children (mean age 9.6 ± 2.4 years, 38 girls) were included in the analysis. The median period of treatment was 9.0 ± 8.5 months (2–9 visits). Twenty-seven (59%) children responded to treatment according to one or both primary outcomes; uroflow configuration (50%) and PVR (28%). DI resolved in 12 (26%) children and 27 of the 32 children, who prior to the treatment had recurrent UTIs experienced no UTIs during the follow up period. The use of anticholinergics was a significant negative predictor for response to treatment. We found that almost half of the responders (48%) reached effect prior to the fourth visit.

      Discussion

      Biofeedback assisted PFMT can improve the symptoms in children with DV. When comparing to existing literature we find a less pronounced effect of the intervention. A possible explanation may be that the children enrolled in this study were recruited from a tertiary referral centre and were all refractory to standard urotherapy. Moreover, the difference in patient characteristics and treatment protocols between different studies make direct comparisons of efficacy difficult.

      Conclusion

      Summary tableEffect parameters evaluated. Data presented as percentages; n, number of patients.
      Number of children with effect
      Dysfunctional voiding pattern on uroflow kurves23 (50%)
      Post-void residual volume (PVR)13 (28%)
      Any effect of the main parameters∗27 (59%)
      Daytime incontinence (DI)11 (24%)
      Recurrent urinary tract infections (n)27 (59%)
      ∗Dysfunctional voiding pattern on uroflow kurves (full and partial effect) and residual urine (children with 50% or more of the uroflowmetry curves showing post-void residual volume (PVR) > 20 ml).

      Keywords

      Introduction

      Dysfunctional voiding (DV) is according to the International Children's Continence Society (ICCS) terminology, defined as the habitual contractions of the urethral sphincter during voiding [
      • Chase J.
      • Austin P.
      • Hoebeke P.
      • McKenna P.
      The management of dysfunctional voiding in children: a report from the Standardisation Committee of the International Children's Continence Society.
      ]. DV in children is a common problem [
      • Palmer L.S.
      Biofeedback in the management of urinary continence in children.
      ], but the exact prevalence is unknown due to challenges in the diagnostics, confusion with terminology and overshadowing by other symptoms. Surveys in children with wetting problems have reported that 4.2%–32% present with DV [
      • Chase J.
      • Austin P.
      • Hoebeke P.
      • McKenna P.
      The management of dysfunctional voiding in children: a report from the Standardisation Committee of the International Children's Continence Society.
      ,
      • Hoebeke P.
      • Van Laecke E.
      • Van Camp C.
      • Raes A.
      • Van De Walle J.
      One thousand video-urodynamic studies in children with non-neurogenic bladder sphincter dysfunction.
      ]. The related symptoms such as daytime incontinence (DI) and urinary tract infections (UTI) is what usually prompts the family to seek advice [
      • Yagci S.
      • Kibar Y.
      • Akay O.
      • Kilic S.
      • Erdemir F.
      • Gok F.
      • et al.
      The effect OF biofeedback treatment ON voiding and urodynamic parameters IN children with voiding dysfunction.
      ], and these symptoms can have a significant negative impact on the child's quality of life [
      • Redsell S.A.
      • Collier J.
      Bedwetting, behaviour and self-esteem: a review of the literature.
      ]. Many children with DV suffer from vesicoureteric reflux (VUR) [
      • Glassberg K.I.
      • Combs A.J.
      • Horowitz M.
      Nonneurogenic voiding disorders in children and adolescents: clinical and videourodynamic findings in 4 specific conditions.
      ] putting them at high risk for recurrent UTI and renal damage [
      • Avlan D.
      • Gündoğdu G.
      • Taşkınlar H.
      • Delibaş A.
      • Naycı A.
      Relationships among vesicoureteric reflux, urinary tract infection and renal injury in children with non-neurogenic lower urinary tract dysfunction.
      ].
      Uroflowmetry, ideally combined with pelvic floor electromyografi (EMG), and measurement of post-void residual volume (PVR) is an essential, non-invasive tool in the diagnosis of DV [
      • Chase J.
      • Austin P.
      • Hoebeke P.
      • McKenna P.
      The management of dysfunctional voiding in children: a report from the Standardisation Committee of the International Children's Continence Society.
      ,
      • Clothier J.C.
      • Wright A.J.
      Dysfunctional voiding: the importance of non-invasive urodynamics in diagnosis and treatment.
      ]. Typical uroflowmetry curves of children with DV show a staccato or intermittent pattern with usually prolonged voiding time and incomplete bladder emptying [
      • Chase J.
      • Austin P.
      • Hoebeke P.
      • McKenna P.
      The management of dysfunctional voiding in children: a report from the Standardisation Committee of the International Children's Continence Society.
      ]. The most prevalent cause of DV is dysfunction of the pelvic floor [
      • Clothier J.C.
      • Wright A.J.
      Dysfunctional voiding: the importance of non-invasive urodynamics in diagnosis and treatment.
      ]. Pelvic floor muscle training (PFMT) with biofeedback is designed as a training technique in which an external electrical sensor is placed to produce signals of physiological functions to influence recorded activity and assist the individual in gaining voluntary control over the pelvic floor [
      • Ladi-Seyedian S.S.
      • Sharifi-Rad L.
      • Nabavizadeh B.
      • Kajbafzadeh A.M.
      Traditional biofeedback vs. Pelvic floor physical therapy-is one clearly superior?.
      ]. For children with DV, biofeedback PFMT teaches the child to identify and relax the external sphincter muscles and pelvic floor during voiding [
      • Palmer L.S.
      Biofeedback in the management of urinary continence in children.
      ]. Before treatment start, neurological or anatomical causes for DV must be excluded [
      • Clothier J.C.
      • Wright A.J.
      Dysfunctional voiding: the importance of non-invasive urodynamics in diagnosis and treatment.
      ]. Furthermore, it is important to identify and treat bowel dysfunction. In a group of children presenting with increased PVR urine, 66% had improvement after treating their constipation [
      • Dohil R.
      • Roberts E.
      • Jones K.V.
      • Jenkins H.R.
      Constipation and reversible urinary tract abnormalities.
      ].
      The present study aimed to evaluate the effect of physiotherapeutic intervention with biofeedback assisted PFMT in children referred with DV not responding to standard urotherapy. Our hypothesis was that treatment could better DV and PVR in these children and prognostic parameters could be identified.

      Material and methods

       Participants and study design

      Children (6–18 years) with DV patterns on uroflowmetry and inadequate effect of urotherapy referred to physiotherapeutic assessment and intervention at the Department of Physio- and Occupational therapy, Aarhus University Hospital, Denmark, between 2013 and 2019, were prospectively included in this study. Exclusion criteria were psychosocial problems, language difficulties, and cognitive issues as these children were not expected to fully adhere to the treatment. Furthermore, children with neurological and anatomical abnormalities of the urinary tract or gastrointestinal tract could not attend the study. The diagnosis of DV was based on repeated uroflowmetry studies showing staccato or interrupted patterns in the majority of pre-treatment uroflowmetries and with evident PF EMG activity [
      • Bauer S.B.
      • Nijman R.J.
      • Drzewiecki B.A.
      • Sillen U.
      • Hoebeke P.
      International Children's Continence Society standardization report on urodynamic studies of the lower urinary tract in children.
      ]. The majority of the children underwent more than one uroflowmetry at each visit and children with only one uroflowmetry examination before or after the intervention were excluded, since we could not establish a secure diagnosis [
      • Chase J.
      • Austin P.
      • Hoebeke P.
      • McKenna P.
      The management of dysfunctional voiding in children: a report from the Standardisation Committee of the International Children's Continence Society.
      ]. All children had undergone several uroflowmetries before the inclusion and throughout the treatment and were comfortable with the method. Ultrasound based PVR urine volume measurements were performed after all uroflowmetries (Bladder Scan BVI-9000, Verathon) and clinically significant PVR was defined as PVR>20 ml [
      • Austin P.F.
      • Bauer S.B.
      • Bower W.
      • Chase J.
      • Franco I.
      • Hoebeke P.
      • et al.
      The standardization of terminology of lower urinary tract function in children and adolescents: update report from the standardization committee of the International Children's Continence Society.
      ]. Information about the child's medical history, recurrent UTI, breakthrough UTI, DI, nocturnal enuresis (NE), constipation according to Rome-IV criteria [
      • Drossman D.A.
      Functional gastrointestinal disorders: history, pathophysiology, clinical features and Rome IV.
      ], faecal incontinence (FI), and other comorbidities were collected. Furthermore, we collected information about prior examinations such as renal ultrasound and voiding cystourethrography (VCUG) from patient's files. The study is a longitudinal prospective intervention study based on consecutive inclusion.

       Intervention

      The physiotherapeutic intervention was focused on teaching the child awareness of the PF, the abdominal muscles and on diaphragmatic breathing. The child was taught to identify and isolate the PF by external palpation of the anal sphincter. Once the child could demonstrate a coordinated voluntary contraction of the PF, the emphasis was put on the relaxation of the PF. The treatment was followed by biofeedback-training with the Solar biofeedback system (MMS, Laborie etc). Surface electromyography electrodes (Ambu-White Sensor WS-electrodes) were placed at two and ten o'clock positions on the anal sphincter to detect the activity of the PF. The Biofeedback system was computer-animated, and the child could activate an object on the screen by respectively contracting and relaxing the PF. The muscle awareness training was done in different positions that increasingly resembled an actual toilet situation, where the optimal voiding posture also was learned. Additionally, the skills were practiced during voiding on a uroflow toilet using surface EMG-electrodes, where the child was instructed to void with a relaxed pelvic floor and anterior abdominal wall, and with no Valsalva. The uroflowmetry and the PF-EMG were recorded during the session and were presented to the child as a visual feedback to reinforce awareness of the muscles. The child was instructed to concentrate on correct toileting posture during voiding and was given home exercises with an individually planned number of sessions, depending on the family resources, for most children 5 times per week. Before and after the physiotherapeutic intervention, the child's symptoms were noted, and uroflowmetry was performed, including measurement of PVR urine volume. The treatment was ended when it by physiotherapeutic assessment was evaluated that the child made no progress.

       Outcome parameters and statistical analysis

      Two primary outcome variables were evaluated at the end of treatment; 1) The normalisation of uroflowmetry pattern; a normalisation in all examinations performed after treatment was noted as a full effect and 50–99% improvement in the quantity of uroflow was considered a partial effect, 2) a reduction in PVR urine in >50% of exanimated flows compared with flows performed before treatment start in children with significant PVR. Secondary effect parameters assessed were the resolution of DI, NE, constipation, FI, and occurrence of UTIs.
      Data is presented as mean ± SD or proportions. Students t-test after testing for normality and chi-squared test were used to evaluate the differences between the responders and non-responders to treatment. A p-value of less than 0.05 was considered statistically significant. Statistical analyses were performed using Stata IC, version 15.0.

       Ethical considerations and consent

      All children with DV and their parents received oral and written information before giving consent to participate. Since the study evaluated the efficacy of a treatment, which did not deviate from normal practice, the study received ethical approval according to Danish law as quality control (Ethics Committee, Region Midt).

      Results

       Patient characteristics

      In the period from 2013 to 2019, 46 children (38 girls) with a mean age of 9.6 ± 2.4 years (6–17 years) and with DV who underwent biofeedback assisted PFMT were included in the study. The average number of uroflowmetry curves accessed was 7.5 ± 4.5 per child. Eight (17%) children were diagnosed with behavioural disorders (four children with Attention Deficit Hyperactivity Disorder or Attention Deficit Disorder (ADHD/ADD), two with autism spectrum disorder, and two with Tourette's syndrome). Before the physiotherapeutic intervention, 34 (74%) of the children suffered from DI, 10 of these were treated for bladder overactivity (tolterodine, mirabegron, solifenacin, or oxybutynin). One child was treated with a-blocker (alfuzosin). Thirty-two (70%) of the children had previously suffered from recurrent UTIs, and 23 (50%) were treated with prophylactic antibiotics. Ten (22%) of the children received laxatives for constipation during the study period (macrogol, microlax, magnesiumoxid, lactulose), and three (7%) children were assessed not to be adequately treated for constipation at the commence of the treatment according to Rome IV criteria [
      • Drossman D.A.
      Functional gastrointestinal disorders: history, pathophysiology, clinical features and Rome IV.
      ]. These were treated for their constipation during the intervention period. Five (11%) children reported FI (Table 1).
      Table 1Demographics and patient characteristics of the participants prior to treatment. Data presented as mean ± SD or percentages; n, number of patients.
      Patients included (46)
      Age at referral (years)9.6 ± 2.4
      Gender (female, n)38 (82%)
      Referral to physiotherapist (Paediatric/urology)37 (80%)/9 (20%)
      Follow up (months)9.0 ± 8.5
      Number of visits (n)4.3 ± 1.9
      Number of flows accessed (n)7.5 ± 4.5
      Behavioral disorder
      ADHD/ADD, autism, Tourette's syndrome.
      (n)
      8 (17%)
      Recurrent urinary tract infections (n)32 (70%)
      Prophylactic antibiotics (n)23 (50%)
      Breakthrough infections (n)12 (26%)
      Daytime incontinence (DI) (n)34 (74%)
      Anticholinergic medicine
      Tolterodine, mirabegron, solifenacin, oxybutynin.
      (n)
      11 (24%)
      Nocturnal enuresis (n)22 (48%)
      Faecal incontinence (n)5 (11%)
      Constipation treatment
      Macrogol, microlax, magnesiumoxid, lactulose.
      (n)
      10 (22%)
      Imaging before treatment
       Ultrasound (n)27 (59%)
       Duplex kidneys (n)3 (11%)
       Hydronephrosis (n)6 (22%)
       Hydroureter (n)3 (11%)
      Voiding cystourethrography (n)31 (67%)
       Unilateral reflux grade III-V (n)3 (10%)
       Bilateral reflux grade III-V (n)2 (6%)
      a ADHD/ADD, autism, Tourette's syndrome.
      b Tolterodine, mirabegron, solifenacin, oxybutynin.
      c Macrogol, microlax, magnesiumoxid, lactulose.
      Most children had undergone imaging examinations before the referral to physiotherapeutic treatment. Twenty-seven (59%) of the children had been subjected to renal ultrasound, 31 (67%) had been exanimated by VCUG. A total of five children were diagnosed with VUR grade III-V on VCUG (Table 1).

       Adherence to the treatment

      Adherence was evaluated by the physiotherapist at each visit. Adherence to the training schedule seemed adequate since 86% of the children followed the clinical visits and reported to perform the exercises at home as instructed. Only two children's adherence was evaluated as poor, with lesser than one training session at home per week. Children with poor compliance were still included in the analysis as we used an intention to treat approach.

       Treatment response

      We found an improvement in voiding patterns in 23 (50%) children; 11 (24%) children had a partial effect and 12 (26%) had complete normalization of uroflowmetry patterns after biofeedback assisted PFMT. Thirteen (28%) children were able to completely empty their bladders. In total, 27 (59%) of all children responded with an improvement in voiding patterns and/or a resolution of their PVR volume. DI resolved in 11 (24%) children. In 27 (59%) of the children who prior to the treatment suffered from recurrent UTI, there was no UTI during and after the treatment. Of those children, 21 were maintained on prophylactic antibiotics. We noticed eight (36%) children with NE became dry dyring the treatment periode, two of these children were on treatment with desmopressin before and during the intervention period, and one child started on desmopressin during treatment with PFMT (Table 2). Two children experienced resolution of their FI. In the main effect parameters (effect on DV patterns and/or PVR volume) responders group 63% improved within the first 4 sessions (Fig. 1). We could not identify any variables which could predict response wihin the first four sessions.
      Table 2Effect parameters evaluated. Data presented as percentages; n, number of patients.
      Number of children with effect
      Dysfunctional voiding pattern on uroflow kurves23 (50%)
      Partial effect11 (24%)
      Complete effect12 (26%)
      Post-void residual volume (PVR)13 (28%)
      Any effect of the main parameters
      Dysfunctional voiding pattern on uroflow kurves (full and partial effect) and residual urine (children with 50% or more of the uroflowmetry curves showing post-void residual volume (PVR) > 20 ml).
      27 (59%)
      Daytime incontinence (DI)11 (24%)
      Nocturnal enuresis8 (17%)
      Recurrent urinary tract infections (n)27 (59%)
      a Dysfunctional voiding pattern on uroflow kurves (full and partial effect) and residual urine (children with 50% or more of the uroflowmetry curves showing post-void residual volume (PVR) > 20 ml).
      Fig. 1
      Fig. 1Kaplan–Meier plot of number of visits prior to response in the main effect parameters (dysfunctional voiding (DV) pattern on uroflow kurves and residual urine (PVR)) in the response group. A response is shown in 48% of the children prior to their fourth visit and 74% prior to their sixth visit.

       Responders vs. non-responders

      There was a significantly higher number of children on anticholinergics who experienced poor response to the training (p < 0.05). We found no difference between DV responders and non-responders regarding age at referral, gender, DI at treatment start, presence of behavioural disorders or recurrent UTIs prior to treatment and VUR (Table 3). Also, no significant difference was found between the responders and non responders concerning children who took medicine to treat constipation.
      Table 3Patient characteristics and treatment parameters. Responders vs. non-responders. Data presented as mean ± SD or percentages.
      Responders (27)Non-responders (19)P-value
      Age at referral9.9 ± 2.89.5 ± 2.40.65
      Gender (girls)21 (78%)17 (89%)0.30
      Daytime incontinence prior to treatment23 (85%)16 (84%)0.93
      Behavioural disorder3 (11%)3 (16%)0.68
      Recurrent urinary tract infections before treatment19 (70%)17 (89%)0.12
      Use of anticholinergics3 (11%)8 (42%)0.032
      Uni- or bilateral reflux grade III-V4 (15%)1 (5%)0.39

      Discussion

      We herein describe the effect of biofeedback assisted PFMT in children with DV refractory to standard urotherapy. We find a response rate of 59% as evaluated by the uroflowmetry patterns and PVR measurements. The improvement in voiding patterns was not reflected in the symptomatology in all children as only one-fourth of the children improved their DI. A positive effect on UTI frequency was evident.
      Children with DV and lower urinary tract symptoms (LUTS) constitute a challenging patient cohort as these children often show resistance to common treatment approaches such as standard urotherapy. Biofeedback is a well-established and widely used method to treat DV, but the effect of the treatment is not adequately elucidated [
      • Tugtepe H.
      • Thomas D.T.
      • Ergun R.
      • Abdullayev T.
      • Kastarli C.
      • Kaynak A.
      • et al.
      Comparison of biofeedback therapy in children with treatment-refractory dysfunctional voiding and overactive bladder.
      ,
      • Alyami F.
      • Ewida T.
      • Alhazmi H.
      • Trbay M.
      • Arafa M.
      • Tahir M.
      • et al.
      Biofeedback as single first-line treatment for non-neuropathic dysfunctional voiding children with diurnal enuresis.
      ,
      • Oktar T.
      • Donmez M.I.
      • Ozkuvanci U.
      • Ander H.
      • Ziylan O.
      Animated versus non-animated biofeedback therapy for dysfunctional voiding treatment: does it change the outcome?.
      ]. Several studies have demonstrated excellent results on LUT symptomatology including day- and night-time symptoms such as DI, UTI, urgency and NE [
      • Vasconcelos M.
      • Lima E.
      • Caiafa L.
      • Noronha A.
      • Cangussu R.
      • Gomes S.
      • et al.
      Voiding dysfunction in children. Pelvic-floor exercises or biofeedback therapy: a randomized study.
      ,
      • Dos Reis J.N.
      • Mello M.F.
      • Cabral B.H.
      • Mello L.F.
      • Saiovici S.
      • Rocha F.E.T.
      EMG biofeedback or parasacral transcutaneous electrical nerve stimulation in children with lower urinary tract dysfunction: a prospective and randomized trial.
      ]. Poor clinical characterisation of the participants, lack of objective assessment of voiding patterns as well as unclear study designs with several concomitant interventions are some of the challenges when comparing results from different studies.
      ICCS recommends standard urotherapy and treatment of potential comorbidities such as constipation before biofeedback training in children with DV as this approach often proves successful [
      • Chase J.
      • Austin P.
      • Hoebeke P.
      • McKenna P.
      The management of dysfunctional voiding in children: a report from the Standardisation Committee of the International Children's Continence Society.
      ]. To address the effectiveness of adding biofeedback to standard urotherapy as first-line treatment, Altunkol et al. performed a study in 45 children diagnosed with DV and showed that the combination of urotherapy and biofeedback was significantly more effective in decreasing urinary incontinence rates, infection rates, and PVR than standard urotherapy alone [
      • Altunkol A.
      • Abat D.
      • Sener N.C.
      • Gulum M.
      • Ciftci H.
      • Savas M.
      • et al.
      Is urotherapy alone as effective as a combination of urotherapy and biofeedback in children with dysfunctional voiding?.
      ]. In a small study by Shei Dei Yang et al. in 20 children, who underwent weekly biofeedback training sessions and practised a relaxation technique at least twice a day at home, they showed that 90% of the children's uroflowmetry patterns normalized [
      • Shei Dei Yang S.
      • Wang C.C.
      Outpatient biofeedback relaxation of the pelvic floor in treating pediatric dysfunctional voiding: a short-course program is effective.
      ]. Other studies have shown a normalization or improvement in voiding patterns in up to 82% of the children [
      • Kibar Y.
      • Ors O.
      • Demir E.
      • Kalman S.
      • Sakallioglu O.
      • Dayanc M.
      Results of biofeedback treatment on reflux resolution rates in children with dysfunctional voiding and vesicoureteral reflux.
      ,
      • Kibar Y.
      • Piskin M.
      • Irkilata H.C.
      • Aydur E.
      • Gok F.
      • Dayanc M.
      Management of abnormal postvoid residual urine in children with dysfunctional voiding.
      ], and a cessation of PF activity on EMG in 90% of the children [
      • Oktar T.
      • Dönmez M.
      • Özkuvancı Ü.
      • Ander H.
      • Ziylan O.
      Animated versus non-animated biofeedback therapy for dysfunctional voiding treatment: does it change the outcome?.
      ]. Biofeedback has also shown to give a resolution of PVR in more than 60% of children [
      • Oktar T.
      • Donmez M.I.
      • Ozkuvanci U.
      • Ander H.
      • Ziylan O.
      Animated versus non-animated biofeedback therapy for dysfunctional voiding treatment: does it change the outcome?.
      ,
      • Kibar Y.
      • Piskin M.
      • Irkilata H.C.
      • Aydur E.
      • Gok F.
      • Dayanc M.
      Management of abnormal postvoid residual urine in children with dysfunctional voiding.
      ]. Our findings show a lesser effect than previously reported when evaluating the uroflowmetry curve configuration and PVR. A possible explanation may be that the children enrolled in this study were recruited from a tertiary referral centre and were all refractory to standard urotherapy. Moreover, the difference in patient characteristics and treatment protocols between different studies makes direct comparisons of efficacy difficult.
      It seems that almost half of the responders (48%) reached effect prior to the fourth visit. We found a large variability of the number of sessions needed to detect response and it has previously been suggested that biofeedback therapy sessions should be continued as long as EMG shows activity during the voiding phase [
      • Kibar Y.
      • Ors O.
      • Demir E.
      • Kalman S.
      • Sakallioglu O.
      • Dayanc M.
      Results of biofeedback treatment on reflux resolution rates in children with dysfunctional voiding and vesicoureteral reflux.
      ,
      • Kibar Y.
      • Piskin M.
      • Irkilata H.C.
      • Aydur E.
      • Gok F.
      • Dayanc M.
      Management of abnormal postvoid residual urine in children with dysfunctional voiding.
      ,
      • Kibar Y.
      • Demir E.
      • Irkilata C.
      • Ors O.
      • Gok F.
      • Dayanc M.
      Effect of biofeedback treatment on spinning top urethra in children with voiding dysfunction.
      ]. Nevzat et al. performed a retrospective study, where two groups of 20 children with DV from two different centres were compared. Group one was treated with four sessions of biofeedback and group two with six to ten sessions of biofeedback. Post-treatment, 90% of children in group one and 95% of children in group two had normalised voiding patterns with no significant difference between the two groups (p > 0.05) [
      • Sener N.C.
      • Altunkol A.
      • Unal U.
      • Ercil H.
      • Bas O.
      • Gumus K.
      • et al.
      Can a four-session biofeedback regimen be used effectively for treating children with dysfunctional voiding?.
      ]. As illustrated in our study, a significant number of children showed response after the initial 4 sessions but even after 8 sessions we identified responders. We could not identify clinical parameters that could predict a faster response to PFMT.
      In our cohort, 24% of the children were on anticholinergics during their physiotherapeutic intervention. Usage of anticholinergics appeared to be a negative prognostic factor as demonstrated by the higher number of children on anticholinergics in the non-responder group. This could reflect the fact that these children are the most treatment-refractory cases and thus more prone to show poor response. Furthermore, anticholinergics alter voiding dynamics and may lead to increased PVR urine volumes. The relatively high percentage of children on anticholinergics may also account for the less pronounced effect compared to prior studies [
      • Oktar T.
      • Donmez M.I.
      • Ozkuvanci U.
      • Ander H.
      • Ziylan O.
      Animated versus non-animated biofeedback therapy for dysfunctional voiding treatment: does it change the outcome?.
      ,
      • Kibar Y.
      • Piskin M.
      • Irkilata H.C.
      • Aydur E.
      • Gok F.
      • Dayanc M.
      Management of abnormal postvoid residual urine in children with dysfunctional voiding.
      ,
      • Porena M.
      • Costantini E.
      • Rociola W.
      • Mearini E.
      Biofeedback successfully cures detrusor-sphincter dyssynergia in pediatric patients.
      ,
      • Krzeminska K.
      • Maternik M.
      • Drozynska-Duklas M.
      • Szczesniak P.
      • Czarniak P.
      • Golebiewski A.
      • et al.
      High efficacy of biofeedback therapy for treatment of dysfunctional voiding in children.
      ].
      The limitations of the present study are the relatively small patient cohort, a short follow-up period, the non-controlled study design and the lack of any symptom questionnaire data or voiding diaries. Also, 7% of the children were assessed not to be adequately treated for constipation at the commence to treatment, and some children were on other medications including prophylactic antibiotics and anticholinergics during treatment, which could influence the results. We used the most clinically important parameters as outcome; uroflowmetry patterns and PVR volumes, and we could also argue that our study cohort is well characterized.

      Conclusion

      Physiotherapeutic treatment with biofeedback assisted PFMT seems to improve outcomes in children with DV refractory to standard urotherapy and pharmacotherapy. We found that 59% of children responded to treatment when evaluating uroflowmetry patterns and PVR volumes. Furthermore, we found a significant reduction in the frequency of UTI after biofeedback. The use of anticholinergics seems to be a negative predictor for response to treatment. A more extensive randomised controlled study on an unselected population of treatment-naive children with DV needs to be performed to gain further insight into the effect of physiotherapeutic intervention with biofeedback assisted PFMT as well as identify prognostic factors.

      Funding

      This research did not receive any specific grant from funding agencies in the public, commercial, or non-for-profit sectors.

      Compliance with ethical standards

      The project was preformed according to the regulations of The Central Denmark Region Committees on Health Research Ethics. Since the study evaluated the efficacy of a treatment, which did not deviate from normal practice, the study received ethical approval according to Danish law as quality control.

      Conflict of interest

      None.

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