Dysfunction of lower urinary tract in patients with spinal cord injury

Developing new ways to assess neural control of pelvic organ function in spinal conditions: ICI-RS 2023

OBJECTIVES

Several central nervous system (CNS) centers affect muscle groups of the lower urinary tract (LUT) and anorectal tract (ART) via autonomic and somatic pathways, working in different modes (storage or expulsion). Hence spinal cord dysfunction can affect the LUT and ART by several possible mechanisms.

METHODS

This review reports the discussions of a workshop at the 2023 meeting of the International Consultation on Incontinence Research Society, which reviewed uncertainties and research priorities of spinal dysfunction.

RESULTS

Discussion focussed on the levator ani nerve, mechanisms underpinning sensory function and sensation, functional imaging, dyssynergia, and experimental models. The following key research questions were identified. (1) Clinically, how can we evaluate the levator ani muscle to support assessment and identify prognosis for effective treatment selection? (2) How can we reliably measure levator ani tone? (3) How can we evaluate sensory information and sensation for the LUT and the ART? (4) What is the role of functional CNS imaging in development of scientific insights and clinical evaluation? (5) What is the relationship of detrusor sphincter dyssynergia to renal failure?

CONCLUSIONS

Spinal cord dysfunction can fundamentally disrupt LUT and ART function, with considerable clinical impact. The evaluation needs to reflect the full scope of potential problems, and new clinical and diagnostic approaches are needed, for prognosis and treatment. The preclinical science evaluating spinal cord function in both LUT and ART storage and elimination remains a major priority, even though it is a challenging experimental context. Without this underpinning evidence, development of new clinical evidence may be held back.

Lower urinary tract function in patients with fracture in thoracolumbal junction: an observational study

A fracture in the thoracolumbal junction may cause complete or incomplete damage to the spinal cord, conus medullaris or cauda equina and result in an isolated or mixed lesion of the upper and lower motor neurons causing leg weakness and urinary/bowel/sexual dysfunction. In this retrospective cross-sectional study, we aimed to describe electrodiagnostic and urodynamic findings after thoracolumbal fractures and determine potential discriminating factors. We identified 74 cases (mean age 42 years, range 16-79 years, 55 men) admitted to our institution between 2008 and 2018 for Th12, L1 or L2 vertebral fractures, and retrieved from their medical records available demographic, clinical, electrodiagnostic and urodynamic data. The most common electrodiagnostic findings in the lower limbs (n = 40) were moderate-to-severe L3-S1 (35%) and L5-S1 (40%) lesions. As to the external anal sphincter (n = 33), the most frequent findings were an incomplete cauda equina (39%) or conus medullaris (15%) lesion, followed by the combined upper and lower motor neuron lesion (12%). Only the fracture level (with peripheral damage) was statistically significantly associated with electromyography findings. Detrusor overactivity or underactivity was each present in 37 (50%) cases. Those with Th12 versus L1-L2 fractures had higher odds of exhibiting detrusor overactivity; men had higher odds of using clean intermittent catheterization for bladder emptying than women. In summary, detrusor overactivity is common after fractures at the thoracolumbal junction and urodynamic findings are essential for proper diagnosis and selection of therapeutic approach. Combining urodynamic and electrodiagnostic studies is especially valuable in the presence of L1 fracture and lower urinary tract symptoms.

A survey of clinical practice concerning long-term follow-up of neurogenic lower urinary tract dysfunction due to spinal cord injury in Italy

CONTEXT/OBJECTIVE

This study aimed to assess the clinical practice for long-term follow-up (FU) of neurogenic lower urinary tract dysfunction (NLUTD) due to spinal cord injury (SCI) in Italy and compare this practice with the clinical practice in other countries and with the international guidelines.

DESIGN

Data concerning the long-term urological FU of individuals with SCI were collected using a questionnaire and analyzed by means of descriptive and inferential statistics.

SETTING

Twenty-one Italian centers following SCI patients.

PARTICIPANTS

One physician at each center (either a permanent staff member or chief).

OUTCOME MEASURES

Questions addressed the treatment of urinary tract infections (UTI), frequency of visits, urinary tract imaging examinations and urodynamic tests (UD), distinguishing between suprasacral and sacral SCI.

RESULTS

Nineteen out of 21 centers completed the survey. In most centers, patients were recommended to undergo a visit and an ultrasound examination of urinary tract (UT) at least once a year. While the median interval between FU visits was identical (12 months) for individuals with suprasacral and sacral SCI, the two interval distributions were significantly different (suprasacral SCI: min-max 4-18, IQR = 6; sacral SCI: min-max 6-24; IQR = 8.5; P = 0.02), showing people with suprasacral SCI are followed up more often. Approximately 80% of the surveyed centers performed scheduled UD, with a yearly median frequency of 12 months (range 6-36) for patients with suprasacral SCI, as compared to a median frequency of 18 months for sacral SCI (range 0-36, P = 0.04). VideoUD and antibiotic prophylaxis for recurrent UTIs are carried out only by urologists in 63% and 47.4% of the centers, respectively. Overall, Italian centers share common strategies that compare to standards, including yearly visits, yearly UT examinations and stricter follow-up of people with suprasacral SCI, but may not have standard protocols for antibiotic prophylaxis of UTI, and in few cases control visits and UD are carried out too often.

CONCLUSIONS

Even though most Italian centers follow up patients with NLUTD secondary to SCI according to international guidelines, heterogeneity in frequency of FU examinations still exists. A tailored approach to the SCI patient that minimizes unnecessary examinations and groups different tests in a single access could improve patients' compliance with FU and reduce costs for the Health system.

Early interventions to prevent lower urinary tract dysfunction after spinal cord injury: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVES

To synthetise the available scientific literature reporting early interventions to prevent neurogenic lower urinary tract dysfunction (NLUTD) after acute supra-sacral spinal cord injury (SCI).

METHODS

The present systematic review is reported according to the PRISMA guidelines and identified articles published through April 2021 in the PubMed, Embase, ScienceDirect and Scopus databases with terms for early interventions to prevent NLUTD after SCI. Abstract and full-text screenings were performed by three reviewers independently, while two reviewers performed data extraction independently. An article was considered relevant if it assessed: an in-vivo model of supra-sacral SCI, including a group undergoing an early intervention compared with at least one control group, and reporting clinical, urodynamic, biological and/or histological data.

RESULTS

Of the 30 studies included in the final synthesis, 9 focused on neurotransmission, 2 on the inflammatory response, 10 on neurotrophicity, 9 on electrical nerve modulation and 1 on multi-system neuroprosthetic training. Overall, 29/30 studies reported significant improvement in urodynamic parameters, for both the storage and the voiding phase. These findings were often associated with substantial modifications at the bladder and spinal cord level, including up/downregulation of neurotransmitters and receptors expression, neural proliferation or axonal sprouting and a reduction of inflammatory response and apoptosis.

CONCLUSIONS

The present review supports the concept of early interventions to prevent NLUTD after supra-sacral SCI, allowing for the emergence of a potential preventive approach in the coming decades.

Serial transurethral cystometry: A novel method for longitudinal evaluation of reflex lower urinary tract function in adult female rats

AIMS

The aim of the study is to develop a minimally invasive method for longitudinal evaluation of lower urinary tract function that allows for simultaneous measurements of bladder pressure and external urethral sphincter (EUS) electromyographic (EMG) activity.

METHODS

To evaluate the reliability of serial transurethral cystometry (STUC), rats (n = 12) underwent three sessions of STUC, one session a week for 3 weeks. During each session, rats were anesthetized with ketamine-xylazine (90 mg/kg and 10 mg/kg), and micturition reflex data were acquired using transurethral cystometry and percutaneous recording of EUS (EMG) activity during continuous infusion of saline into the bladder. The reliability and consistency of the STUC method were assessed using intra-class correlation (ICC) analysis and repeated measures ANOVA.

RESULTS

ICC values calculated from five successive events during the first micturition session indicate good to excellent reliability for measurements of peak bladder pressure, threshold bladder pressure, minimum bladder pressure, volume threshold, duration of EUS bursting, and number of EUS burst events. Across the three recording sessions no significant difference was observed in peak bladder pressure, threshold bladder pressure, minimum bladder pressure, volume threshold, number of EUS burst events, and duration of EUS bursting using repeated measures ANOVA.

CONCLUSION

Serial transurethral cystometry under ketamine-xylazine anesthesia with simultaneous percutaneous EUS EMG recording is a novel, reliable, accurate, and minimally invasive method for quantitative assessment of lower urinary tract (LUT) function in adult female rats over extended periods of time.

Effects of Wnt5a overexpression in spinal cord injury

Accordingly to its known function in corticospinal tract (CST) developmental growth, previous reports have shown an inhibitory role of Wnt5a in CST regeneration after spinal cord injury (SCI). Interestingly, it has been subsequently demonstrated that Wnt5a also modulates the developmental growth of non‐CST axons and that different Wnt5a receptors are expressed in neurons, oligodendrocytes, NG2+ glial precursors and reactive microglia/macrophages and astrocytes after SCI. However, the role of Wnt5a in the response of these cell types, in the regeneration of non‐CST axons and in functional recovery after SCI is currently unknown. To evaluate this, rats were subjected to spinal cord contusion and injected with a lentiviral vector generated to overexpress Wnt5a. Histological analyses were performed in spinal cord sections processed for the visualization of myelin, oligodendrocytes, neurons, microglia/macrophages, astrocytes, NG2+ glial precursors and serotonergic axons. Motor and bladder function recovery were also assessed. Further advancing our knowledge on the role of Wnt5a in SCI, we found that, besides its previously reported functions, Wnt5a overexpression elicits a reduction on neuronal cell density, the accumulation of NG2+ glial precursors and the descending serotonergic innervation in the affected areas, along with impairment of motor and bladder function recovery after SCI.

Selective Recording of Urinary Bladder Fullness from the Extradural Sacral Roots. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020;2020:3873-3876. [PMID: 33018846 DOI: 10.1109/embc44109.2020.9176038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Managing the urinary bladder is of primary importance to clinicians and patients after trauma to the spinal cord. Sacral Anterior Root Stimulators that control the bladder have been available as clinical technology for many years, however these devices cannot measure the fullness of the urinary bladder or detect the onset of reflex voiding. In order to address this fundamental limitation, it is necessary to develop a method for recording the neural signals that encode bladder fullness. This paper presents a proof of concept technique for recording bladder afferents from the extradural sacral roots using a multiple electrode cuff. Results are provided from acute in-vivo experiments performed in sheep.

Functional and structural changes of the urinary bladder following spinal cord injury; treatment with alpha lipoic acid

BACKGROUND & AIM

Alpha lipoic acid (LA) was shown to exert neuroprotection in trauma-induced spinal cord injury (SCI), which is frequently associated with urinary bladder complaints in patients with SCI. Accordingly, the protective effects of LA on biochemical and histological changes in bladder as well as functional studies were assessed.

METHODS

Wistar albino rats were divided as control, SCI, and LA (50 mg/kg/day, ip) treated SCI groups (SCI+LA). The standard weight-drop (100 g/cm force at T10) method was used to induce a moderately severe SCI. One week after the injury, neurological examination was performed and the rats were decapitated. Bladder samples were taken for histological examination, functional (isolated tissue bath) studies, and for the measurement of biochemical parameters (malondialdehyde, MDA; gluthathione, GSH; nerve growth factor, NGF; caspase-3, luminol and lucigenin chemiluminescences).

RESULTS

SCI caused a significant (P < 0.001) increase in the detrusor muscle thickness. It increased the contractility responses to carbachol and relaxation responses to papaverine (P < 0.05-0.001). There were also significant alterations in MDA, caspase-3, luminol, and lucigenin chemiluminescences with concomitant decreases in NGF and GSH (P < 0.05). LA treatment reversed histological and functional (contraction and relaxation responses) changes induced by SCI (P < 0.05-0.001), but no significant recovery was observed in the impaired neurological functions.

CONCLUSION

These results indicate that LA have a beneficial effect in improving the bladder tonus via its antioxidant and anti-inflammatory actions following SCI.