Short Pelvic Floor Electromyographic Lag Time: A Novel Noninvasive Approach to Document Detrusor Overactivity in Children with Lower Urinary Tract Symptoms

Time until maximum flow rate uroflowmetry: A new parameter for predicting failure of transcutaneous electrical nerve stimulation (TENS) in treating children and adolescents with overactive bladder

AIM

To analyze uroflowmetry as a predictor of the outcome of treatment with parasacral transcutaneous electrical nerve stimulation (TENS) in patients with pure overactive bladder.

METHODS

Thirty-eight patients of 5-16 years of age were included in this prospective cohort study. All the patients had been seen at a referral clinic between 2006 and 2015. All had a diagnosis of pure overactive bladder and were treated with TENS. Parameters established at pretreatment uroflowmetry were evaluated, with patients then being separated into two groups based on their visual analogue scale (VAS) score immediately following TENS. The variables analyzed at uroflowmetry were: maximum flow rate, curve pattern (bell or tower-shaped), time until maximum flow and voided volume.

RESULTS

The mean age of the children evaluated was 7.26 years (SD: 2.62) (95%CI: 6.4-8.13) and 73.7% were girls. No association was found between maximum flow rate, curve pattern (bell or tower-shaped) or voided volume and the complete resolution of symptoms following treatment. Nevertheless, a shorter time until maximum flow was associated with a greater likelihood of treatment failure.

CONCLUSION

The time until maximum flow rate before treatment is a potential predictor of the outcome of TENS treatment.

Is there a unique symptom in lower urinary tract dysfunction in children?

OBJECTIVES

Lower urinary tract symptoms (LUTS), particularly urgency, incontinence and intermittency are common in children and it is suggested that the specific symptoms may be used for definite diagnosis for LUT dysfunction (LUTD). This study was performed to investigate the relationship between each LUTD and its associated symptoms, using uroflowmetry/electromyography (UF/EMG) as a diagnostic tool.

METHODS

Each patient was categorized into one of four LUT conditions which were overactive bladder (OAB), dysfunctional voiding (DV), underactive bladder and primary bladder neck dysfunction (PBND), according to UF/EMG results. Patients' complaints and findings were documented by using voiding dysfunction symptom score, bladder diary, urine analysis and ultrasonography. In addition, a detailed history of bowel habits (including use of Rome III criteria) was obtained.

RESULTS

There were 189 children of which 106 were female. The OAB was the largest group including 91 patients, followed by the DV group which had 61 patients. The symptoms specific to any LUTD group were constipation and hesitancy (P < .05). Hesitancy was present in 89.4% with PBND and constipation was present in 78.6% of patients with DV. None of other symptoms were able to differentiate any LUTD group from the other.

CONCLUSIONS

While certain symptoms are often presumed by clinicians to imply specific diagnoses, the main outcome of this study is that there is a generally weak correlation between the specificity of symptoms and LUTD. Symptoms-based approach may lead to misdiagnosis in LUTD. Thus, it may be essential to focus on the underlying pathologies and UF/EMG test may help this.

Medical evaluation and management of male and female voiding dysfunction: a review

A significant workforce shortage of urologists available to serve the US population has been projected to occur over the next decade. Accordingly, much of the management of urologic patients will need to be assumed by other specialties and practitioners. Since primary care physicians are often first evaluate common urologic complaints, it makes sense that these physicians are in an excellent position to intervene in the management of these patients when appropriate. One of the most common complaints in urology is voiding dysfunction. The incidence of voiding dysfunction increases with age, with conservative estimates showing that over 50% of elderly patients suffer. Despite this high prevalence and its negative impact on quality of life, however, few seek or receive treatment, as many do not readily disclose these impactful yet personal symptoms. We sought to summarize the typical presentation, evaluation, assessment and therapeutic options for both male and female patients presenting with voiding dysfunction.

Usefulness of the classification of urinary dysfunction for the prognosis of the first endoscopic treatment of vesicoureteral reflux in children over the age of 3

OBJECTIVES

To assess the diagnostic performance of urinary dysfunction patterns associated with vesicoureteral reflux (VUR) in children over the age of 3 according to the result of the first endoscopic treatment (ENDT1), grouped into a classification designed by our group (CMD.URI-La Fe). Comparison with other current classifications such as that of Van Batavia et al. MATERIAL AND METHODS: Ambispective cross-cutting study of a sample of 50 children.

EXCLUSION CRITERIA

previous ENDT, age ≤ 3 years, anatomical or neurological anomalies and a history of ureteral or abdominopelvic surgery. Prior to the ENDT1, a bladder voiding function assessment by uroflowmetry+electromyography (UF-EMG) and post-mictional residue (ultrasound). Other variables from the bladder diary, pre-mictional bladder wall thickness and other clinical variables. The correction of VUR was assessed by isotope cystography 3 months after the treatment. Urinary patterns were classified according to the significant variables (URI-La Fe), and the diagnostic performance of this classification was assessed, comparing it to the classification of patients as proposed by Van Batavia et al. RESULTS: Mean age: 6.8±2.28 years. Males/females (44%/56%). Grades of VUR (mild/moderate/severe). ENDT1 VUR correction rate: 77% (n=38). Diagnostic performance (Van Batavia; URI-La Fe): correct prediction (37.5%; 75%), sensitivity (32.4%; 87.8%), specificity (54.5%; 46.6%), positive predictive value (70.6; 78.3%) and negative predictive value (19.4%; 63.6%).

CONCLUSIONS

Our results show the usefulness of the non-invasive test and the classification of urinary dysfunction in children aged over 3 years prior to the first endoscopic treatment of VUR.

The Role of Non-invasive Testing in Evaluation and Diagnosis of Pediatric Lower Urinary Tract Dysfunction

PURPOSE OF REVIEW

The symptoms of lower urinary tract dysfunction (LUTD) including urinary incontinence, frequency, and urgency are among the most common reasons children are referred to pediatric urologists. Despite this, the workup for LUTD is often time consuming and a source of frustration for patients, parents, and clinicians alike. In the current review, we summarize the important role non-invasive testing plays in the diagnosis and management of children with LUTD and to show how use of these tests can help avoid the need for more invasive testing in the majority of children.

RECENT FINDINGS

Non-invasive tests such urine studies, uroflowmetry ± simultaneous electromyography, assessment of post-void residual, renal/bladder ultrasound, and pelvic ultrasound when used appropriately can provide valuable information to facilitate decision making during the evaluation of children with LUTD. While these tests should be employed prior to more invasive testing such as urodynamic studies, they can often act as a surrogate for the more invasive tests. Non-invasive tests can help us in our goal of improving diagnostic ability to better classify the child's LUTD into an actual condition which allows targeted treatment in the hope of better outcomes and more satisfied patients and families.

Overactive bladder (OAB): A symptom in search of a disease - Its relationship to specific lower urinary tract symptoms and conditions

BACKGROUND

The ICCS defines OAB by the subjective symptom of urgency; detrusor overactivity (DO) is only implied. While no other symptom is required, OAB can also be associated with urinary frequency, decreased functional bladder capacity, and incontinence.

OBJECTIVE

We sought to determine how often these associated findings occur in OAB and what if any uroflow/EMG-defined conditions are found to be associated with it.

METHODS

The charts of 548 children (231M, 318F; mean age 9.0 years, range 3-20) who presented sequentially with urgency (OAB), over a period of 2 years, were reviewed paying particular attention to whether or not there was a history of frequency and/or daytime incontinence in addition to the urgency. All patients had been previously diagnosed with one of the following four lower urinary tract (LUT) conditions based on specific uroflow/EMG findings: 1. dysfunctional voiding (DV; active pelvic floor EMG during voiding); 2. idiopathic detrusor overactivity disorder (IDOD; OAB with a short EMG lag time (<2 s), and quiet pelvic floor EMG during voiding); 3. detrusor underutilization disorder (DUD; willful infrequent voiding with %EBC >125%, quiet EMG during voiding); and 4. primary bladder neck dysfunction (PBND; prolonged EMG lag time (>6 s), quiet EMG during voiding, and depressed uroflow curve). Mean %EBC was compared between patients with urgency alone and those with urgency plus other symptoms. Any association with gender was analyzed.

RESULTS

Urgency was accompanied by either frequency or daytime incontinence in 91% of the children (summary Table). Daytime incontinence was reported in 398 (72.6%) and frequency in 268 (48.9%). Mean %EBC was 80.9. Females were more likely to report daytime incontinence (76.7% vs. 66.7%, p = 0.02) and frequency was found more often in males (63.6% vs. 38.1%, p < 0.001). %EBC was less in males (70.0 vs. 88.8, p < 0.001). The majority of patients with urgency were diagnosed with IDOD (62%), while 15% had DV, 5% PBND, 3% DUD, and in 15%, the uroflow/EMG was not diagnostic.

CONCLUSIONS

%EBC was usually normal or mildly increased in OAB when urgency is the only symptom but significantly decreases with each additional LUTS. OAB is more common in girls and they tend to have a lower incidence of frequency, more incontinence, and >%EBC than boys. Because urgency in an anatomically and neurologically normal child is the only required criterion for diagnosing OAB, it must be realized that OAB can be associated with any of a number of objectively defined LUT conditions. Thus OAB appears to be a symptom, not a condition, that is often associated with other symptoms.

ICS Educational Module: Electromyography in the assessment and therapy of lower urinary tract dysfunction in adults

AIM

To present the teaching module "Electromyography in the assessment and therapy of lower urinary tract dysfunction in adults." This teaching module embodies a presentation, in combination with this manuscript. This manuscript serves as a scientific background review; the evidence base made available on ICS website to summarize current knowledge and recommendations.

METHODS

This review has been prepared by a Working Group of The ICS Urodynamics Committee. The methodology used included comprehensive literature review, consensus formation by the members of the Working Group, and review by members of the ICS Urodynamics Committee core panel.

RESULTS

Electromyography (EMG) is a method to record spontaneous or artificially induced electrical activity of the nerve-muscle unit or to test nerve conductivity. EMG of the anal sphincter using surface electrode is most widely used screening technique to detect detrusor-sphincter dyssynergia in urology. It is non-invasive and easy to perform. EMG methods using needle electrodes are reserved for diagnostics in well selected group of mainly neurogenic patients. These methods require expertise in the field of general EMG and are usually performed by neurologist and neuro-physiologist. The evidence in many aspects of use of EMG in urology remains sparse.

CONCLUSIONS

Currently EMG methods rarely play a decision making role in selecting proper treatment of lower urinary tract dysfunction. With the current efforts to improve phenotyping of these patients in order to provide individualized treatment, the role of EMG could increase.

Refractory Urinary Incontinence in Girls: The Role of the Bladder Neck

BACKGROUND

Prevalence of lower urinary tract dysfunction (LUTD) in children is between 6 and 9% with urinary incontinence (UI) being one of the most common symptom.

VARIOUS ASPECTS OF LOWER URINARY TRACT SYMPTOMS LUTS

Anatomical anomalies of the urinary tract as well as neurogenic underlying pathology can results in LUTS. Comorbidities and long-term consequences of the LUTD for the female patients as well as genetic issues are also briefly discussed.

THE ROLE OF THE BLADDER NECK

Thanks to urodynamics, we have learnt a lot about the lower urinary tract function, but the role of the bladder neck in the pathophysiology of LUTS in children is not clear. Secondary bladder neck hypertrophy is a well-described pathology, but there is no standardized treatment for this phenomenon. Primary bladder neck dysfunction has already been defined by the International Children's Continence Society.

REFRACTORY UI IN GIRLS

Uniform diagnostic protocols are used in these girls with UI. Treatment consists of standard urotherapy, additional interventions, and pharmacotherapy in selected cases. Those with refractory UI require careful reassessment to look for the unrecognized disorders. Invasive urodynamics should be done in those patients. Ultrasound of the bladder neck region and the pelvic floor can be helpful, but its interpretation is very subjective. In a small group bladder neck insufficiency can be found and those might benefit from a surgical intervention.

FUTURE PERSPECTIVE

Strict criteria of the bladder neck insufficiency in children must be defined. Early surgical intervention in girls with bladder neck insufficiency might reduce the long period of intensive conservative treatment.

Can children with either overactive bladder or dysfunctional voiding transition from one into the other: Are both part of a single entity?

BACKGROUND

In 1998 it was postulated by the ICCS that urge syndrome, later termed overactive bladder (OAB), and dysfunctional voiding (DV) might not be separate entities and instead represent transitional stages between each other, and that DV may be the evolutionary end product of OAB. The aim of this study was to determine not only if OAB sometimes transitions into DV but also if the reverse occurs, and, if so, might they indeed be parts of one entity.

MATERIALS AND METHODS

To create an objective study of these two conditions, specific "qualifiers" supporting the diagnosis of each condition were introduced: 1) DV included the qualifier of an active EMG during voiding on two studies; 2) OAB included the qualifiers of a short lag time (<2 s) as a surrogate for detrusor overactivity (DO) and a quiet EMG during voiding. Two separate cohorts (one for DV and one for OAB) of 77 consecutive patients each were reviewed. All DV patients were treated with biofeedback and some with antimuscarinics. All OAB patients were treated with antimuscarinics. Both cohorts also received standard therapy and bowel management when indicated. All patients had multiple uroflow/EMG evaluations before and during therapy and were followed for a minimum of 6 months.

RESULTS

Mean follow-up was 17.5 months and median age at diagnosis was 6.6 years for DV and 6.4 years for OAB. Of the OAB children none transitioned into DV, although two demonstrated transient DV-like EMG activity on interval testing that did not require biofeedback. Of DV children, following the initiation of biofeedback therapy, the EMG became quiet on follow-up uroflow/EMG after a mean of 9.3 months in 70 of 77 (91%). With EMG quieting, however, a short EMG lag time suggesting DO became apparent in those children with persistent irritative symptoms. This short lag time became apparent in 25 of 31 (81%) children treated with biofeedback alone versus only 8 of 39 (21%) on biofeedback plus antimuscarinics.

CONCLUSION

OAB with qualifiers and DV are two distinct LUT conditions and children do not appear to transition from the one to the other. While some children with DV did demonstrate a short lag time during follow-up, this is because once the EMG quieted in response to biofeedback, it improved our ability to document the already existing DO secondary to their previous DV. A dysfunctional voiding sequence with the postulated initial step being the transition of OAB into DV does not seem to be likely as the age at initial diagnosis was similar in both groups.

Uroflowmetry with pelvic floor electromyography: inter-rater agreement on diagnosis of pediatric non-neurogenic voiding disorders

INTRODUCTION

Uroflowmetry with electromyography (uroflow-EMG) is commonly used for evaluation of lower urinary tract (LUT) function in children. Diagnostic criteria based largely on uroflow-EMG findings have previously been proposed for several conditions collectively termed non-neurogenic voiding disorders (NNVDs). These include dysfunctional voiding (DV), idiopathic detrusor overactivity disorder (IDOD), detrusor underutilization disorder (DUD), and primary bladder neck dysfunction (PBND). It is unknown whether practitioners with varying levels of training and experience can apply the diagnostic criteria for these conditions with a high level of consistency.

OBJECTIVE

To assess inter-rater agreement on diagnosis of NNVDs using uroflow-EMG studies.

STUDY DESIGN

Six raters performed post hoc evaluation of 84 uroflow-EMG studies and associated clinical data from children with symptoms of LUT dysfunction and no evidence of neurologic or anatomic abnormalities. Each rater was asked to categorize the uroflow-EMG studies as being consistent with DV, IDOD, DUD, PBND, or normal/unclassifiable. A consensus diagnosis was noted for studies on which at least four raters agreed. Inter-rater agreement was assessed via calculation of unweighted Fleiss' kappa statistics.

RESULTS

Overall inter-rater agreement on NNVD diagnoses was moderate (kappa 0.46, 95% CI 0.38-0.54). Agreement between individual raters ranged from 0.33 (fair) to 0.74 (substantial) (Figure). There was no consensus on diagnosis for 20 patients (24%).

DISCUSSION

Several factors may contribute to inter-rater disagreement on diagnosis of NNVDs. These include instances where patients satisfy one criterion for a particular diagnosis while missing others - or have findings consistent with more than one diagnosis. Strategies to address this may involve simplifying the diagnostic criteria, developing a clear algorithm that prioritizes certain criteria, and/or allowing assignment of multiple diagnoses. Practitioners could also benefit from standardized education regarding the diagnostic criteria for NNVDs. Potential limitations of this analysis included the use of just one uroflow-EMG study per patient in almost all cases. Also, the raters had variable levels of previous experience using the diagnostic criteria for NNVDs, and it is possible that they were not always applied as originally intended. If this were the case, it would support development of a standardized education tool to facilitate practitioner understanding and application of the criteria.

CONCLUSIONS

Uroflow-EMG has shown promise for improving clinical management of NNVDs associated with pediatric LUT dysfunction. However, inter-rater agreement on NNVD diagnoses using current criteria is suboptimal. Various mechanisms should be explored to improve consistency in practitioners' diagnosis of NNVDs.

Flowmetry/ pelvic floor electromyographic findings in patients with detrusor overactivity

To evaluate different flowmetry/EMG patterns in patients with proven detrusor overactivity (DO) and compare them with that of a group of patients with lower urinary tract symptoms (LUTS) but without DO.

MATERIALS AND METHODS

We retrospectively evaluated the records of 100 patients with frequent urinary tract infection or any kind of storage or voiding symptoms that had undergone urodynamic testing: 50 cases with proven DO on cystometry who had a good quality flowmetry/EMG and 50 patients without DO. EMG lag time (the time distance between pelvic floor EMG inactivation and the start of urine flow) and different flow curve pattern were recorded and compared.

RESULTS

The age and gender distribution were not statistically significant between the two groups. A negative lag time (≤ 0 sec) and an obstructive pattern were the only parameters that were more commonly seen in the DO group. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of a lag times <2 sec for diagnosing DO were 70%, 96%, 96% and 72%, respectively. For a negative lag time, they were 52%, 100%, 100% and 63%, respectively.

CONCLUSIONS

A lag time <2 sec is a useful flowmetric finding that effectively rules out patients with LUTS that do not have DO (specificity and PPV=96%). With the cutoff of zero or less, specificity and PPV will be 100%. It has lower sensitivity and NPV, however, and is not measurable in a considerable population of patients with DO that have concomitant DV.

The bladder of willful infrequent voiders: underactive or underutilized?

OBJECTIVE

We previously described a lower urinary tract (LUT) condition (detrusor underutilization disorder, DUD) characterized by chronic or episodic willful deferment of voiding resulting in an expanded capacity in patients with LUT symptoms. We now further characterize these DUD patients.

MATERIALS AND METHODS

We reviewed our database identifying neurologically/anatomically normal children diagnosed with DUD. Bladder capacity had to be at least >125% EBC for age to be included. LUTS, diaries and uroflow/EMG findings were analyzed.

RESULTS

Fifty-five children (mean age 10.5 years, range 3.7-20.2; 34F, 19M) with LUTS were diagnosed with DUD. The most common reasons for presentation included incontinence (43.6%), history of urinary tract infection (UTI) (49.1%), and urgency (30.9%). Mean percent estimated bladder capacity for age was 1.67 and following treatment mean %EBC decreased to 1.10.

CONCLUSIONS

DUD patients typically present with infrequent voiding, incontinence, urgency, and UTIs. They have less bowel dysfunction and frequency, and larger bladder capacities than typically found in children with overactive bladder and dysfunctional voiding. Although the symptoms associated with DUD overlap in part with those considered by the International Children's Continence Society to be typical for "underactive bladder" and "voiding postponement", DUD, we feel, is a stand-alone diagnosis.

Use of non-invasive uroflowmetry with simultaneous electromyography to monitor patient response to treatment for lower urinary tract conditions

OBJECTIVE

Non-invasive uroflowmetry with simultaneous electromyography (uroflow/EMG) has previously been reported as effective in triaging patients into four specific non-neurogenic lower urinary tract (LUT) conditions for targeted treatment. In this study we sought to determine if the same parameters would be useful for measuring response to treatment.

MATERIAL AND METHODS

We reviewed our database of normal children with LUT dysfunction, screened with uroflow/EMG, and diagnosed with a LUT condition: (1) dysfunctional voiding (DV); (2) idiopathic detrusor overactivity disorder (IDOD); (3) detrusor underutilization disorder (DUD); (4) primary bladder neck dysfunction (PBND). Pre- and on-treatment (minimum 3 months) uroflow/EMG parameters and subjective improvements were compared.

RESULTS

Of 159 children (71 boys, 88 girls; median age 7.0 years, range 3.5-18.0 years), median follow up was 13.1 months (range 3-43 months). On targeted treatment, DV patients showed relaxation of pelvic floor during voiding and significant decrease in PVR on biofeedback; IDOD patients had normalization of short lag time and increased capacity on antimuscarinics; DUD patients had a decrease in capacity on timed voiding; PBND patients on alpha-blocker therapy showed improved uroflow rates and a decrease in mean EMG lag time (all p < 0.05).

CONCLUSION

Non-invasive uroflow/EMG is useful not only for diagnosing specific LUT conditions, but also in objectively monitoring treatment efficacy. Subjective improvement on targeted therapy correlates well with objective improvements in uroflow/EMG parameters lending validation to this simplified approach to diagnosis.

Short pelvic floor EMG lag time II: use in management and follow-up of children treated for detrusor overactivity

OBJECTIVE

To determine utility of short pelvic floor electromyography (EMG) lag time in monitoring therapeutic response in children with idiopathic detrusor overactivity (DO) and quiet EMG during voiding (idiopathic detrusor overactivity disorder, IDOD).

PATIENTS AND METHODS

162 consecutive normal children (77M, 85F) diagnosed with IDOD and short EMG lag time were reviewed. All were treated with combined standard urotherapy and anticholinergics. Pre-treatment uroflow/EMG parameters were compared with on-treatment parameters.

RESULTS

Median age at evaluation was 6.8 years and median EMG lag time was 0 s; 110 children had repeat uroflow/EMG studies while on anticholinergic therapy. With a median follow-up of 18.7 months, mean EMG lag time increased from 0.7 to 2.2 s and % expected bladder capacity for age (EBC) increased from 0.68 to 0.98 (both p < 0.01). EMG lag time increased in all patients while on therapy and normalized in 83 patients (75%).

CONCLUSION

A short EMG lag time on noninvasive uroflow/EMG in a patient with urgency can be a surrogate for urodynamics study (UDS) in diagnosing DO and objectively monitoring response to therapy. When effectively treated, children with DO have amelioration of their lower urinary tract symptoms (LUTS) and normalization of both EMG lag time and bladder capacity.