Role of urodynamic studies in the diagnosis and treatment of lower urinary tract symptoms

Ultrasound shear wave elastography cannot discriminate between low- and high-pressure neurogenic bladders

BACKGROUND

Patients with neurogenic bladders are monitored with renal bladder ultrasounds and video urodynamics studies (VUDS) to assess upper urinary tract injury. Ultrasound shear wave elastography (US-SWE) can assess tissue stiffness. If bladder compliance is affected by bladder wall fibrosis and stiffening, then high-pressure bladders may be detectable by US-SWE therefore reducing the need for VUDS in some patients.

OBJECTIVE

To determine if US-SWE can differentiate between low- and high-pressure bladders and hence be used for noninvasive assessment of neurogenic bladder in children.

STUDY DESIGN

Prospective study of patients with neurogenic bladder undergoing clinically indicated VUDS between February and July of 2017. During VUDS, bladder wall US-SWE was measured at different filling percentages of estimated bladder capacity (EBC). The bladders were divided into cohorts according to the detrusor muscle pressure (P_det) reached at the maximum bladder capacity: normal (1 to <15 cmH₂O) and abnormal (≥15 cmH₂O) pressure. T-test was used to compare elastography values at different bladder volumes and P_det; (statistical significance set at p < 0.05).

RESULTS

30/31 enrolled children completed the protocol. With an empty bladder, as well as at all other bladder volumes, no relationship was observed between P_det and mean SWE of the anterior or posterior bladder wall. At maximum bladder capacity, there was no difference between mean SWE values of the anterior or posterior bladder walls in those with normal pressure, 2.97 m/s (SD ± 0.82) and 1.96 m/s (SD ± 0.75), compared to those with abnormal pressures 3.08 m/s (SD ± 0.84) and 2.39 m/s (SD ± 0.96), p = 0.75 and p = 0.2, respectively.

DISCUSSION

We found no difference between SWE values of either the anterior or posterior bladder wall in neurogenic bladders with normal and abnormal filling pressures measured during VUDS. Our study differs from previously reported studies with more positive results in that our cut-off for abnormal bladder pressure was (P_det ≥15 cmH₂O). This is lower than the more commonly used leak point pressure of 40 cmH₂O because our practice is to intervene earlier. Moreover, SWE would be most useful if it can identify changes before the bladder has reached such severe conditions, to allow for early intervention. Additional differences between ours and other studies include US manufacturer and younger age of the participating children.

CONCLUSIONS

US-SWE, while feasible, was not able to discriminate between low- and high-pressure bladders. Moreover, US-SWE did not show significant correlation with the current gold standard, VUDS.

Tissue engineering in reconstructive urology-The current status and critical insights to set future directions-critical review

Advanced techniques of reconstructive urology are gradually reaching their limits in terms of their ability to restore urinary tract function and patients' quality of life. A tissue engineering-based approach to urinary tract reconstruction, utilizing cells and biomaterials, offers an opportunity to overcome current limitations. Although tissue engineering studies have been heralding the imminent introduction of this method into clinics for over a decade, tissue engineering is only marginally applied. In this review, we discuss the role of tissue engineering in reconstructive urology and try to answer the question of why such a promising technology has not proven its clinical usability so far.

Urodynamic Values Role For Females With Different Types Of Urinary Incontinence

Aim — The aim of this study was to analyse how conventional urodynamic values differ between females with specific types of urinary incontinence (UI). Material and Methods — Cross-sectional study enrolled 666 females with UI. Based on patient history and questionnaires they were divided into three groups: stress (SUI), mixed (MixUI) and urgency (UUI). Physical investigation and urodynamics were performed. The continuous factors: age and urodynamic data were evaluated using Multinomial regression and ANOVA test using SUI, MixUI, UUI as outcome groups. Results — Analysing urodynamic parameters significant difference between at least two groups was shown by the cystometric capacity and maximum flow rate: both highest in the SUI group; residual urine, opening detrusor pressure, maximum urethral closure pressure at rest, functional urethral length at rest: all highest in the UUI group. Mainly all urodynamic data showed significant difference between SUI/UUI, and MixUI/UUI groups, while difference between SUI/MixUI were not significant. Conclusions — Most of urodynamic data for MixUI group patients do not differ from SUI group. UDS parameters like: maximum flow rate, residual urine, opening detrusor pressure, maximum urethral closure pressure at rest, functional urethral length at rest can help to distinguish SUI and MixUI groups from UUI group.

Auxiliary Tests of Autonomic Functions

SUMMARY

The autonomic nervous system is a complex neural network that controls several organ systems. Its assessment includes a detailed history of autonomic functions, clinical examination, and autonomic tests. Most widely used is a battery of tests that assess cardiovascular reflex autonomic and sudomotor tests, which include deep breathing (assesses parasympathetic function), Valsalva maneuver, tilt test (both assess parasympathetic and adrenergic functions), and sudomotor testing for the evaluation of postganglionic sudomotor fibers. These basic tests represent a foundation of autonomic testing. Nevertheless, the autonomic nervous system also controls organ systems not directly assessed by basic tests. This review describes a number of auxiliary autonomic tests that can be used in addition to basic autonomic tests or can be used independently to explore particular autonomic functions or to answer a specific clinical question. The auxiliary tests described in this review evaluate cardiovascular, thermoregulatory, gastrointestinal, genitourinary, eye, and exocrine functions. These tests are cold pressor test, sustained handgrip maneuver, reverse tilt test, venoarteriolar reflex, laser Doppler flare imaging, microneurography, neck suction, lower body negative pressure, venous occlusion plethysmography, pharmacologic assessment of postganglionic sympathetic outflow, plasma norepinephrine, sympathetic skin response, video cinefluoroscopic swallowing test, esophageal manometry test, small bowel manometry test, wireless motility capsule test, urodynamic studies, penile plethysmography, intracavernosal papaverine injection, infrared video pupillography, corneal confocal microscopy, pupillary response to dilute pilocarpine and hydroxyamphetamine, Schirmer test, tear osmolarity test, and salivary secretion test. The protocol of each test is described in detail. This review can be used as a quick reference for the auxiliary autonomic tests.

Stem Cell Therapy for Neurogenic Bladder Dysfunction in Rodent Models: A Systematic Review

PURPOSE

Neurogenic bladder dysfunction (NGB) has an impact on the quality of life, which made it an important research subject in preclinical studies. The present review investigates the effect of stem cell (SC) therapy on bladder functional recovery after the onset of spinal cord injury (SCI), multiple sclerosis (MS), Parkinson disease (PD), and stroke in rodent models.

METHODS

All experiments evaluated the regenerative potential of SC on the management of NGB in rodent models up to June 2019, were included. From 1,189 relevant publications, 20 studies met our inclusion criteria of which 15 were conducted on SCI, 2 on PD, 2 on stroke, and 1 on MS in the rodent models. We conducted a meta-analysis on SCI experiments and for other neurological diseases, detailed urodynamic findings were reported.

RESULTS

The common SC sources used for therapeutical purposes were neural progenitor cells, bone marrow mesenchymal SCs, human amniotic fluid SCs, and human umbilical cord blood SCs. There was a significant improvement of micturition pressure in both contusion and transaction SCI models 4 and 8 weeks post-SC transplantation. Residual urine volume, micturition volume, and bladder capacity were improved 28 days after SC transplantation only in the transaction model of SCI. Nonvoiding contraction recovered only in 56 days post-cell transplantation in the contusion model.

CONCLUSION

Partial bladder recovery has been evident after SC therapy in SCI models. Due to limitations in the number of studies in other neurological diseases, additional studies are necessary to confirm the detailed mechanism for bladder recovery.

Cauda equina syndrome: false-positive diagnosis of neurogenic bladder can be reduced by multichannel urodynamic study

BACKGROUND

The present consensus suggests urgent surgical decompression if clinical features of cauda equina syndrome (CES) are supported by MRI evidence of pressure on cauda equina. However, clinical diagnosis has a high false-positive rate and MRI is a poor indicator. Though urodynamic studies (UDS) provide objective information about the lower urinary tract symptoms experienced by patients including neurogenic bladder, its role in the diagnosis of CES is not established.

OBJECTIVE

To evaluate the ability of an objective urological assessment protocol using uroflowmetry + USG-PVR as screening test and invasive UDS as confirmatory test in patients with suspected CES to rule out neurological impairment of the bladder function.

METHODS

A retrospective study was conducted on all patients who were referred to our institution with equivocal findings of cauda equina syndrome from January 2014 to December 2018 with positive MRI findings. An algorithm using multichannel UDS was followed in all the included patients.

RESULTS

Out of 249 patients who fulfilled the inclusion criteria, 34 patients (13.65%) had normal uroflowmetry and USG-PVR findings; 211 patients underwent the invasive UDS. Only 141(57.6%) patients out of 245 patients had neurovesical involvement due to compression of cauda equina; 67 patients were treated conservatively using the objective protocol. Only one patient treated conservatively had to undergo emergency decompression for deterioration in symptoms.

CONCLUSIONS

Multichannel UDS provides an objective diagnostic tool to definitively establish the neurovesical involvement in CES. Utilising multichannel UDS as an adjunct to clinical findings avoids the probability of false-positive diagnosis of CES. These slides can be retrieved under Electronic Supplementary Material.

Risk factors for febrile genito-urinary infection in the catheterized patients by with spinal cord injury-associated chronic neurogenic lower urinary tract dysfunction evaluated by urodynamic study and cystography: a retrospective study

INTRODUCTION

To investigate the risk factors for febrile genito-urinary tract infection (GUTI) in spinal cord injury-associated neurogenic lower urinary tract dysfunction (NLUTD) patients who perform routine clean intermittent catheterization (CIC) evaluated by urodynamic study (UDS) and cystography.

PATIENTS AND METHODS

Over a 3-year period, we retrospectively assessed risk factors for febrile UTI in 141 spinal cord injury patients diagnosed as NLUTD and performing routine CIC, regarding gender, UDS findings such as bladder compliance, maximum cystometric capacity, and cystography.

RESULTS

A total of 41 patients had febrile GUTI in the follow-up period as along with 32 cases of pyelonephritis, 10 cases of epididymitis, and 1 case of prostatitis, including patients with multiple infectious diseases. The causative bacteria were Escherichia coli (14 cases) followed by Pseudomonas aeruginosa (n = 5), Klebsiella pneumoniae (n = 4), and Klebsiella oxytoca (n = 4). Antibiotic-resistant E. coli were seen, with 36.4% instances of extended-spectrum beta-lactamase production in whole of E. coli. Male gender (p = 0.018), ASIA Impairment Scale (AIS) C or more severe (p = 0.031), the number of CIC (p = 0.034), use of quinolones (p < 0.001) and severe bladder deformity (DG 2 or more, p = 0.004) were significantly associated with febrile GUTI occurrence.

CONCLUSIONS

Our data demonstrated that male gender, severe bladder deformity (DG 2 or more), AIS C or more, the number of CIC, and use of quinolones were significantly associated with febrile GUTI occurrence in NLUTD patients employing routine CIC. Further prospective studies are necessary to define the full spectrum of possible risk factors for febrile GUTI in these patients.

Long-Term Efficacy of Mirabegron Add-On Therapy to Antimuscarinic Agents in Patients With Spinal Cord Injury

Objective

To evaluate the long-term efficacy of mirabegron add-on therapy in patients with spinal cord injury (SCI) based on an urodynamic study.

Methods

This retrospective study involved a chart audit of individuals with SCI who underwent two consecutive urodynamic studies between April 1, 2015 and April 1, 2018. After adding 50 mg of mirabegron once a day to the pre-existing antimuscarinic therapy for a period of, at least 6 months, the following variables were analyzed: change in cystometric capacity, change in bladder compliance, change in maximal detrusor pressure, change in reflex volume, and presence of significant leakage during filling cystometry.

Results

A total of 31 participants with a mean age of 41±15 years were included in the analysis. A significant increase in cystometric capacity (mean, 362 to 424 mL; p=0.03), reflex volume (mean, 251 to 329 mL; p=0.02), and bladder compliance (median, 12 to 18 mL/cmH₂O; p=0.04) was observed. The presence of leakage during filling cystometry was significantly reduced (29% to 10%; p=0.03). Likewise, a non-significant decrease in the change in maximal detrusor pressure was observed (mean, 31 to 27 cmH₂O; p=0.39).

Conclusion

Adding mirabegron to conventional antimuscarinics further improved urodynamic parameters in patients with chronic SCI, and sustained efficacy was observed in long-term use.

Rationales for a Urodynamic Study in Patients with Cervical Spondylotic Myelopathy

BACKGROUND

Detrusor sphincter dyssynergia, involuntary detrusor contractions (IDCs), and poor bladder compliance are common urodynamic findings in cervical spondylotic myelopathy (CSM). There is little information regarding the role of a urodynamic study after decompression surgery for CSM.

METHODS

Urodynamic study was performed before and 6 months after decompression of CSM. Japanese Orthopaedic Association score for cervical myelopathy and Neck Disability Index functional score were applied. International Prostate Symptom Score was applied in male patients, and 6-item Urogenital Distress Inventory was applied in female patients.

RESULTS

Mean patient age was 61.3 years. Final follow-up was obtained in 17 of 32 patients. Neurogenic bladder was confirmed in 11 (64.7%) patients, with 7 patients having poor bladder compliance, 3 patients having IDCs, and 6 patients having detrusor sphincter dyssynergia. Poor bladder compliance was normalized in 4 of 7 patients. IDCs disappeared in 2 (phasic IDCs) of 3 patients and improved in 1 (terminal IDC) patient. Detrusor sphincter dyssynergia markedly improved in 4 of 6 patients. Bladder compliance in 17 patients was 45.52 ± 23.71 before decompression surgery and 77.07 ± 39.85 after decompression surgery (P = 0.004). Both Japanese Orthopaedic Association and Neck Disability Index scores improved (P = 0.007 and P = 0.001, respectively). International Prostate Symptom Score and 6-item Urogenital Distress Inventory were not changed 6 months after surgery.

CONCLUSIONS

Neurogenic bladder could be partially controlled in patients with CSM after surgical decompression. The neurogenic component in the urodynamic study findings varied. Depending on the findings, further appropriate urologic treatments after neurologic decompression surgery should be considered.

Urinary incontinence due to lumbar spinal stenosis causing disability and lowering quality of life

OBJECTIVES

Lumbar spinal stenosis may lead to urinary inconsistence and can have a negative impact on the quality of life. The aim of the study was to assess the incidence of urinary incontinence and quality of life in female patients with spinal canal stenosis comparing to control group.

METHODS

The study population consisted of 50 women diagnosed with severe lumbar spinal canal stenosis. Their mean age was 55.32 ± 12.97 years. The clinical control group consisted of 30 women who did not suffer from any spine disorders. Their mean age was 54.87 ± 12.01 years. There was no difference between both groups regarding age, weight, BMI and number of parity. The women diagnosed with clinical and radiographic symptoms of spinal canal stenosis filled out an anonymous questionnaire, ODI, ICIQ-UI-SF, and ICIQ-LUTSqol questionnaires.

RESULTS

We found urinary incontinence in 56% of women with lumbar spinal canal stenosis and in 43% of clinical control group. We also found a statistically significant correlation between duration of lumbar stenotic symptoms, the SLR sign, number of deliveries and the intensity of urinary incontinence.

CONCLUSIONS

Urinary incontinence in women with lumbar spinal canal stenosis is significantly different from the control group. Leakage of urine happened more frequently, the amount of urine leaked was greater, and the general impact on everyday life is harsher, as compared to the clinical control group.

Closed-loop stimulation of the pelvic nerve for optimal micturition

OBJECTIVE

Neural stimulation to restore bladder function has traditionally relied on open-loop approaches that used pre-set parameters, which do not adapt to suboptimal outcomes. The goal of this study was to examine the effectiveness of a novel closed-loop stimulation paradigm for improving micturition or bladder voiding.

APPROACH

We compared the voiding efficiency obtained with this closed-loop framework against open-loop stimulation paradigms in anesthetized rats. The bladder pressures that preceded voiding, and the minimum current amplitudes for stimulating the pelvic nerves to evoke bladder contractions, were first calibrated for each animal. An automated closed-loop system was used to initiate voiding upon bladder fullness, adapt the stimulation current by using real-time bladder pressure changes to classify voiding outcomes, and halt stimulation when the bladder had been emptied or when the safe stimulation limit was reached.

MAIN RESULTS

In vivo testing demonstrated that the closed-loop system achieved high voiding efficiency or VE (75.7%  ±  3.07%, mean  ±  standard error of the mean) and outperformed open-loop systems with either conserved number of stimulation epochs (63.2%  ±  4.90% VE) or conserved charge injected (32.0%  ±  1.70% VE). Post-hoc analyses suggest that the classification algorithm can be further improved with data from additional closed-loop experiments.

SIGNIFICANCE

This novel approach may be applied to an implantable device for treating underactive bladder (<60% VE), especially in cases where under- or over-stimulation of the nerve is a concern.