Neurogenic Bladder and Urodynamic Outcomes in Patients with Spinal Cord Myelopathy

Automated closed-loop stimulation to inhibit neurogenic bladder overactivity

Individuals with spinal cord injury (SCI) usually develop neurogenic detrusor overactivity (NDO), resulting in bladder urgency and incontinence, and reduced quality of life. Electrical stimulation of the genital nerves (GNS) can inhibit uncontrolled bladder contractions in individuals with SCI. An automated closed-loop bladder neuromodulation system currently does not exist but could improve this approach. We have developed a custom algorithm to identify bladder contractions and trigger stimulation from bladder pressure data without need for abdominal pressure measurement. The goal of this pilot study was to test the feasibility of automated closed-loop GNS using our custom algorithm to identify and inhibit reflex bladder contractions in real time. Experiments were conducted in a single session in a urodynamics laboratory in four individuals with SCI and NDO. Each participant completed standard cystometrograms without and with GNS. Our custom algorithm monitored bladder vesical pressure and controlled when GNS was turned on and off. The custom algorithm detected bladder contractions in real time, successfully inhibiting a total of 56 contractions across all four subjects. There were eight false positives, six of those occurring in one subject. It took approximately 4.0 ± 2.6 s for the algorithm to detect the onset of a bladder contraction and trigger stimulation. The algorithm maintained stimulation for approximately 3.5 ± 1.7 s, which was enough to inhibit activity and relieve feelings of urgency. Automated closed-loop stimulation was well-tolerated and subjects reported that algorithm decisions generally matched with their perceptions of bladder activity. The custom algorithm automatically, successfully identified bladder contractions to trigger stimulation to inhibit bladder contractions acutely. Closed-loop neuromodulation using our custom algorithm is feasible, but further testing is needed refine this approach for use in a home environment.

Sensations Reported During Urodynamic Bladder Filling in Spinal Cord Injury Patients Give Additional Important Information

Purpose

To study sensations reported during filling cystometry in patients with different levels and completeness of spinal cord lesion (SCL).

Methods

A retrospective cohort study. Patient age and sex, cause of SCL, American Spinal Injury Association Impairment Scale (AIS), and lower urinary tract -related sensations in daily life were gathered. Filling cystometry (video-urodynamics) was performed following ICS good urodynamic practice guidelines. Beside bladder filling sensations (first sensation of bladder filling, first desire to void, strong desire to void), other sensations as detrusor overactivity related sensation and pain were noted.

Results

170 patients were included, age 45 ± 17 years, 114 male and 56 female, 92 complete and 78 incomplete SCL. The test was done 6 ± 4 years post SCL. Sensation was reported by 57% of all patients. In complete SCL half (46/92) had sensation, while 36% with incomplete SCL (28/78) reported no sensation. Bladder awareness was not predictable by the AIS. The filling sensations reported were equal to those given in the terminology of ICS. Pain was seldom present 10/170 (6%), Detrusor overactivity contraction was felt by 45/78 ( 58%). Very few patients used sensory information for bladder management at home.

Conclusion

After SCL, most patients retain the ability to be aware of the LUT, assessable and gradable, during urodynamic testing. Filling sensations were not different from those described in healthy, but the number and sequence of the sensations were altered in the minority. Pain and sensation of unstable contractions gave additional important information. As different sensations relate to different spinal afferent pathways, the sensory evaluation during cystometry provided additional important information on the spinal cord's condition.

Incidence, prognosis, and risk factors for bladder and bowel dysfunction due to incidental dural tears in lumbar microendoscopic surgery

BACKGROUND CONTEXT

Despite the common occurrence of incidental dural tears, the incidence and prognosis of bladder and bowel dysfunction (BBD) due to incidental dural tears in lumbar spinal surgery are not well known because of the lack of reported cases.

PURPOSE

To analyze the incidence, prognosis, and risk factors for BBD after lumbar microendoscopic surgery with or without incidental dural tears.

STUDY DESIGN/SETTING

A retrospective cohort study.

PATIENT SAMPLE

We analyzed 2,421 patients who underwent lumbar microendoscopic surgery and investigated patients with BBD after an incidental durotomy during surgery.

OUTCOME MEASURES

Patients were divided into three groups on the basis of dysuria and defecation disorders: severe BBD, mild BBD, and no BBD. The post void residual volumes before and after surgery were compared using an ultrasound bladder scanner or bladder catheterization after confirmation of urination. Bowel dysfunction was evaluated by subjective symptomatic deterioration and the increase in the frequency and duration of postoperative medical care.

METHODS

Risk factors for BBD were analyzed using surgical video documentation to determine the dural tear site and cauda equina exposure from the dural sac. Patients with BBD were prospectively followed up for prognosis determination. The chi-square test was used to compare the incidence of BBD between patients with dural tears and those without. Propensity score-adjusted logistic regression analysis was performed to evaluate the effects of various factors on the incidence of postoperative BBD.

RESULTS

The incidence of dural tears was 6.9% (168/2,421). The overall incidence of BBD was 3.0% (73/2,421), while the incidences of BBD (mild+severe BBD) and severe BBD due to incidental dural tears were 1.2% (30/2,421) and 0.8% (20/2,421), respectively. The incidence of BBD in patients with dural tears and those without tears was 17.9% [30/168] and 1.9% [43/2,253; p<.001]), respectively. BBD rates at 1 week, 1 month, 3 months, 6 months, and 1 year after surgery were 64.0%, 44.0%, 40.0%, 28.0%, and 13.6%, respectively. Logistic regression analysis revealed that the male sex (odds ratio [OR], 4.20), dural tears in the central area (OR, 10.15), and exposure of the cauda equina (OR, 51.04) were significant risk factors.

CONCLUSIONS

The incidence of dural tears in lumbar microendoscopic surgeries are associated with an increased incidence of BBD. The recovery rate for BBD due to incidental dural tears is generally good; however, some patients experience long-term symptoms. Clinicians should be aware that incidental dural tears with cauda equina exposure can increase the risk of BBD.

At-home genital nerve stimulation for individuals with SCI and neurogenic detrusor overactivity: A pilot feasibility study

OBJECTIVE

Neurogenic bladder dysfunction, including neurogenic detrusor overactivity (NDO) is one of the most clinically significant problems for persons with spinal cord injury (SCI), affecting health and quality of life. Genital nerve stimulation (GNS) can acutely inhibit NDO-related reflex bladder contractions and increase bladder capacity. However, it is unknown if GNS can improve urinary continence or help meet individuals' bladder management goals during sustained use, which is required for GNS to be clinically effective.

DESIGN

Subjects maintained voiding diaries during a one-month control period without stimulation, one month with at-home GNS, and one month after GNS. Urodynamics and quality of life assessments were conducted after each treatment period, and a satisfaction survey was taken at study completion.

SETTING

Subject screening and clinical procedures were conducted at the Louis Stokes Cleveland VA Medical Center. Stimulation use and voiding diary entries were conducted in subjects' homes.

PARTICIPANTS

Subjects included five men with SCI and NDO.

INTERVENTIONS

This study tested one month of at-home portable non-invasive GNS.

OUTCOME MEASURES

The primary outcome measure was leakage events per day. Secondary outcome measures included self-reported subject satisfaction, bladder capacity, and stimulator use frequency.

RESULTS

GNS reduced the number of leakage events from 1.0 ± 0.5 to 0.1 ± 0.4 leaks per day in the four subjects who reported incontinence data. All study participants were satisfied that GNS met their bladder goals; wanted to continue using GNS; and would recommend it to others.

CONCLUSIONS

Short term at-home GNS reduced urinary incontinence and helped subjects meet their bladder management goals. These data inform the design of a long-term clinical trial testing of GNS as an approach to reduce NDO.

Important Clinical Rehabilitation Principles Unique to People with Non-traumatic Spinal Cord Dysfunction

Background: Non-traumatic spinal cord dysfunction (SCDys) is caused by a large range of heterogeneous etiologies. Although most aspects of rehabilitation for traumatic spinal cord injury and SCDys are the same, people with SCDys have some unique rehabilitation issues. Purpose: This article presents an overview of important clinical rehabilitation principles unique to SCDys. Methods: Electronic literature search conducted (January 2017) using MEDLINE and Embase (1990-2016) databases for publications regarding SCDys. The focus of the literature search was on identifying publications that present suggestions regarding the clinical rehabilitation of SCDys. Results: The electronic search of MEDLINE and Embase identified no relevant publications, and the publications included were from the authors' libraries. A number of important clinical rehabilitation principles unique to people with SCDys were identified, including classification issues, general rehabilitation issues, etiology-specific issues, and a role for the rehabilitation physician as a diagnostic clinician. The classification issues were regarding the etiology of SCDys and the International Standards for Neurological Classification of Spinal Cord Injury. The general rehabilitation issues were predicting survival, improvement, and rehabilitation outcomes; admission to spinal rehabilitation units, including selection decision issues; participation in rehabilitation; and secondary health conditions. The etiology-specific issues were for SCDys due to spinal cord degeneration, tumors, and infections. Conclusions: Although there are special considerations regarding the rehabilitation of people with SCDys, such as the potential for progression of the underlying condition, functional improvement is typically significant with adequate planning of rehabilitation programs and special attention regarding the clinical condition of patients with SCDys.

Testing of a New Portable Device for Dynamic Bladder Pressure Monitoring

OBJECTIVE

To develop a portable dynamic bladder pressure monitoring device for facilitating the monitoring of bladder detrusor pressure in patients with neurogenic bladder (NB) caused by spinal cord injury and further compared the effect with traditional urodynamics devices.

METHODS

Portable dynamic bladder pressure monitoring device was implemented by software and hardware. The hardware was mainly composed of seven parts, such as micro liquid pressure sensor, electric bridge amplifying circuit, clock module, SD card storage circuit, liquid crystal display circuit, touch circuit, controller circuit and so on. The main program of the software included system initialization, data acquisition, storage, display, alarm, etc. A total of 45 patients with neurogenic bladder caused by spinal cord injury were enrolled in the study. Detrusor pressure was measured with the portable device and traditional urodynamics device.

RESULTS

The test-retest reliability of the portable device was modest in two times test (intra-class correlation coefficient (ICC) = 0.852), no significant difference was found in the results of volume perfusion evaluation between our device and conventional urodynamic (each P > 0.05).

CONCLUSION

The portable dynamic bladder pressure monitoring device is conducive to the dynamic monitoring of bladder pressure in patients with neurogenic bladder caused by spinal cord injury.