Bladder-filling sensation in patients with spinal cord injury and the potential for sensation-dependent bladder emptying

Urodynamic findings and therapeutic approaches for neurogenic lower urinary tract dysfunction in patients with thoracic spinal cord injury

OBJECTIVES

To evaluate urodynamic examination results and treatment methods of neurogenic lower urinary tract dysfunction (NLUTD) in patients with traumatic thoracic spinal cord injury (SCI).

METHODS

Ninety-one patients with traumatic thoracic SCI were included in the study. The urodynamic analyses of the patients were conducted retrospectively using their laboratory outcomes. The patients were divided into subgroups according to the sensory innervation of the bladder (T1-10/T11-12), the preservation of sensory functions in the sacral segment (complete lesion/incomplete lesion), and the duration of injury (< 6 months/ ≥ 6 months) and evaluations in subgroups were carried out.

RESULTS

A total of 91 patients (69 males, 22 females) were included in the study. When comparing between the subgroups, the sense of bladder fullness was preserved more in the T11-T12 group with a statistically significant difference (p < 0.001). While storage disorder, the rate of indwelling catheter use during hospitalization, bacterial growth of 105 CFU/ml in the urine culture, and anticholinergic drug recommendation after urodynamic examination were higher in the complete lesion group, the rate of spontaneous/catheter-free voiding, the number of patients in which sense of bladder fullness was preserved-partially preserved, and alpha-blocker drug recommendation after urodynamic examination was higher in the incomplete lesion group, with a statistically significant difference in all parameters (all p values < 0.05).

CONCLUSION

Our results demonstrate that there are differences in neurogenic lower urinary tract dysfunction features in subgroups of traumatic thoracic SCI patients. Regular urinary system evaluation and necessary changes in treatment should be carried out in this patient group.

Disruption of sensation-dependent bladder emptying due to bladder overdistension in a complete spinal cord injury: A case report

BACKGROUND

Autonomic dysreflexia (AD) can be a life-threatening condition in patients with spinal cord injury. It is important to prevent bladder overdistension in these patients as it may trigger AD. Sensation-dependent bladder emptying (SDBE), as a method of bladder management, improves the quality of life and allows physiologic voiding. In this study, we report disruption of the SDBE habit after bladder overdistension leading to AD with chest pain.

CASE SUMMARY

A 47-year-old male with a diagnosis of C4 American Spinal Cord Injury Association impairment scale A had been emptying his bladder using the clean intermittent catheterization method with an itchy sensation in the nose as a sensory indication for a full bladder for 23 years, and the usual urine volume was about 300-400 mL. At the time of this study, the patient had delayed catheterization for approximately five hours. He developed severe abdominal pain and headache and had to visit the emergency room for bladder overdistension (800 mL) and a high systolic blood pressure (205 mmHg). After control of AD, a hypersensitive bladder was observed despite using anticholinergic agents. The sensation indicating bladder fullness changed from nose itching to pain in the abdomen and precordial area. Moreover, the volume of the painful bladder filling sensation became highly variable and was noted when the bladder urine volume exceeded only 100 mL. The patient refused intermittent clean catheterization. Finally, a cystostomy was performed, which relieved the symptoms.

CONCLUSION

Patients using physiologic feedback, such as SDBE, for bladder management are recommended to avoid bladder overdistension.

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.

The Video-Urodynamic and Electrophysiological Characteristics in Patients With Traumatic Spinal Cord Injury

Purpose

To investigate the video-urodynamic and pelvic floor electrophysiological characteristics in patients with traumatic spinal cord injury.

Methods

This retrospective reviewed the clinical records, urodynamic and pelvic floor electrophysiological data of 647 patients with traumatic spinal cord injury (SCI) and out of spinal shock. Patients were classified based on American Spinal Injury Association (ASIA) Impairment Scale and urodynamic findings.

Results

Of the 647 patients, detrusor overactivity (DO) with or without detrusor sphincter dyssynergia (DSD) was found in 79.5%, 61%, 35.2%, 35%, and 19.2% of patients with cervical, thoracic (T1-9), thoracic (T10-12), lumbar, and conical cauda injury, respectively. Other patients manifested detrusor areflexia (DA). Patients with DO and/or DSD had a longer duration of SCI at each injury level than patients with DA. In suprasacral injury patients with DA, 63.0% (58/92) had a normal bulbocavernosus reflex (BCR) response. Compared with patients without bladder sensation, bladder capacity during urine leakage was far higher in those with bladder sensation. The manifestation of BCR and somatosensory-evoked potential (SEP) was associated with the level of injury.

Conclusions

This study showed a significant correlation between the level of SCI and video-urodynamic findings, but clinical examination cannot by predict bladder function; urodynamic testing is also necessary. In addition, the role of BCR and SEP for guiding bladder management is limited. Moreover, bladder sensation is important for urinary control in patients with traumatic SCI.

Combining different evaluations of sensation to assess the afferent innervation of the lower urinary tract after SCI

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To study a combination of three evaluations of sensation in the lower urinary tract (LUT) in patients with spinal cord injury (SCI).

SETTING

University Antwerp Belgium, Unicenter study.

METHODS

Evaluation of perineal sensation with light digital touch, reporting of filling sensation during a standardised urodynamic investigation and determination of the electrical perception threshold (EPT) were evaluated in patients with SCI.

RESULTS

150 individuals were included: 97 men and 53 women, mean age 46 ± 17 years. Patients had different levels and completeness of SCI, and different techniques for bladder emptying. Seventy-four patients (49%) reported sensation to touch in the perineal area. Sensation of bladder filling was reported in different patterns by 81 patients (54%). EPT was determined in 69 patients of which 50 (72%) reported sensation in different patterns. The outcome of absence/presence of sensation between the three tests differed greatly: with perineal sensation absent 53% had filling sensation (p = 0.040) and 58% positive EPT (p = 0.009). With filling sensation absent 59% had EPT sensation (not significant). Perineal sensation was strongly associated with level and completeness of SCI, while a significant association existed for filling sensations FSF, FDV, SDV and EPT in the distal urethra.

CONCLUSIONS

Our study shows that different evaluations of sensation in the LUT of individuals with SCI complement each other. and we therefore propose combined use in the urological evaluation of patients with SCI to allow a more complete picture of the LUT sensations.

Ambulatory urodynamic monitoring assessment of dorsal genital nerve stimulation for suppression of involuntary detrusor contractions following spinal cord injury: a pilot study

STUDY DESIGN

A prospective interventional pilot study using within-individual comparisons.

OBJECTIVES

To assess the effect of dorsal genital nerve stimulation (DGNS) on urine-storage parameters in participants with spinal cord injury (SCI) and neurogenic detrusor overactivity (NDO) during natural bladder filling.

SETTING

The London Spinal Cord Injuries Centre at the Royal National Orthopaedic Hospital, Stanmore, UK.

METHODS

Ambulatory urodynamic monitoring (AUM) was carried out with and without DGNS, before and after a week of using DGNS at home. DGNS was applied on-demand by four participants with bladder sensation, and both continuously and intermittently by one participant with absent sensation. A Wilcoxon sign-rank test was used to test paired results of changes within an AUM session.

RESULTS

Urodynamic outcomes were improved using DGNS. Bladder capacity was increased from 244 ± 59 to 346 ± 61 ml (p = 0.0078), a mean change of 46 ± 25%. Maximum detrusor pressure was decreased from 58 ± 18 to 47 ± 18 cmH2O (p = 0.0156), a change of 17 ± 13%, and average peak detrusor pressure was decreased from 56 ± 16 to 31 ± 128 cmH2O (p = 0.0156), a mean reduction of 50 ± 19%. There was an increase in the number of detrusor contractions from the first involuntary detrusor contraction to a strong desire, urgency or incontinence, from 1.5 ± 1.4 to 4.3 ± 1.7, and an increase in time of 23 ± 22 min. There were no changes in baseline outcomes following home use of DGNS.

CONCLUSIONS

DGNS may be applied on-demand, intermittently or continuously, to increase bladder capacity, decrease storage pressures and provide extra time. Improvements were made in addition to existing antimuscarinic medication regimes.

Change in urodynamic pattern and incidence of urinary tract infection in patients with traumatic spinal cord injury practicing clean self-intermittent catheterization

Objective: To observe changes in cystometric parameters in individuals with spinal cord injury (SCI) with neurogenic bladder practicing clean intermittent self-catheterization (CIC) and incidence of urinary tract infection (UTI) in such patients.Design: Prospective, observational study.Setting: Tertiary Urban Rehabilitation Hospital.Participants: Persons with neurogenic bladder caused by traumatic SCI and practicing CIC.Interventions: Clinical evaluation, complete urine analysis, urine culture and sensitivity, ultrasonography of the abdomen and urodynamic study were evaluated at baseline and at follow-up (6 months to 1 year).Outcome Measures: Detrusor pattern, cystometric capacity, detrusor compliance, detrusor leak point pressure, residual urine, incidence of UTI.Results: Thirty-one participants were included in the study. The baseline cystometric study showed that 15 had overactive detrusor and 16 had detrusor areflexia. The mean cystometric capacity decreased significantly between baseline and follow-up in both the groups but remained within the normal threshold limit, decline being more marked in the overactive detrusor group, who also had more marked decrease in compliance. Mean detrusor leak point pressure was below 40 cm H₂O in all participants in both groups at baseline and follow-up. Mean residual urine improved at follow-up in both groups. Incidence of UTI was 2.29 episodes per patient per year, and more frequent in the overactive detrusor group. Escherichia coli was the causative agent in 45%.Conclusion: The cystometric capacity and compliance decreased significantly though patients were doing regular CIC and managed on antimuscarinics for detrusor overactivity (DO). UTI is more common in individuals with SCI with DO and E. coli is the most common cause of UTI.

The management of neurogenic lower urinary tract dysfunction after spinal cord injury

The management of patients with neurogenic bladder has changed substantially over the past decades. Obtaining balanced lower urinary tract function has become possible in most patients, although, urological complications remain among the most serious complications these patients are likely to have and, even today, these can have a negative effect on quality of life. To this extent, patients with spinal cord injury (SCI) are likely to develop neurogenic bladder, and data are available on most aspects of neurogenic bladder in these patients. Data on physiology and pathophysiology form the basis of our understanding of patients' symptoms, and also provide a basis for the management of these patients. The use of conservative, and/or more invasive treatment measures, their complications and measures to prevent these complications, are all important clinical aspects that merit discussion. Considerable progress has been made in the urological management of patients with SCI over the past decades, but opportunities remain to make diagnosis more accurate and therapy more successful.

An unresolved relationship: the relationship between lesion severity and neurogenic bladder in patients with spinal cord injury

OBJECTIVES

We aimed to investigate the relationship between the severity of the spinal lesion and urodynamic findings, bladder drainage method at discharge, and incidence of renal calculi in patients with spinal cord injury (SCI). STUDYDESIGN: Retrospective.

SETTING

In-patient rehabilitation unit of a tertiary research hospital.

METHODS

A total of 131 patients who were admitted to our clinic with a diagnosis of SCI and placed into a rehabilitation program were included in the study. The severity of the lesion was determined according to the American Spinal Injury Association Impairment Scale (AIS). We evaluated the relationship between the severity of the lesion and the detrusor hyperactivity and compliance as determined by urodynamic investigation, the bladder drainage method used at discharge, and the renal calculi rate as determined by ultrasonography.

RESULTS

While no difference was found between the patients with complete and incomplete injuries in terms of age, sex, disease duration, detrusor hyperactivity and compliance, the bladder drainage method was found to show a significant change according to the severity of the lesion. None of the patients were found to have hydronephrosis and the rate of renal calculi showed no statistically significant difference according to the severity of the lesion.

CONCLUSIONS

We concluded that urodynamic examination is required in each patient with SCI as the severity of the lesion is not sufficient to determine the bladder type, and patients with complete and incomplete injuries should be monitored with the same sensitivity in terms of complications.

Urodynamic findings, bladder emptying methods and therapeutic approaches in patients with upper lumbar and lower lumbar-sacral spinal cord injury

There have been previous reports of both demographic and clinical features with urodynamic evaluation results of patients with traumatic spinal cord injury (SCI). These studies were conducted on patients with cervical and thoracal SCI, but there has been no comparative study evaluating the urodynamic outcomes of patients with lumbosacral SCI. Therefore, it was aimed to investigate the bladder features and treatment options in patients with lumbosacral SCI to be able to take appropriate therapeutic decisions. The urodynamic data of 121 patients with lumbar and sacral SCI were obtained retrospectively using the urodynamics unit records. The patients were grouped as upper lumbar (L1 and L2) SCI (ULSCI) and lower lumbar-sacral (L3 to S5) SCI (LLSSCI). The patients were 92 males (76 %) and 29 (24 %) females, comprising 74 (61.2 %) ULSCI patients and 47 (38.8 %) LLSSCI patients. Detrusor hypocompliancy and anticholinergic prescription were more frequent in the ULSCI group than in the LLSSCI group, while alpha-blocker prescription was more frequent in the LLSSCI group than in the ULSCI group. There was a statistically significant difference between the groups in respect of the rates of bladder-emptying method on admission. A higher mean micturated urine volume was observed in the LLSSCI group than in the ULSCI group. The rates of bladder-filling sensation, detrusor overactivity, bladder-storage and emptying disorders, prescribed emptying method, and residual urine volume were similar in both groups. These results showed that there are differences in neurogenic bladder features and treatment options for patients with upper lumbar and lower lumbar-sacral SCI.

The effect of spinal cord injury on the neurochemical properties of vagal sensory neurons

The vagus nerve is composed primarily of nonmyelinated sensory neurons whose cell bodies are located in the nodose ganglion (NG). The vagus has widespread projections that supply most visceral organs, including the bladder. Because of its nonspinal route, the vagus nerve itself is not directly damaged from spinal cord injury (SCI). Because most viscera, including bladder, are dually innervated by spinal and vagal sensory neurons, an impact of SCI on the sensory component of vagal circuitry may contribute to post-SCI visceral pathologies. To determine whether SCI, in male Wistar rats, might impact neurochemical characteristics of NG neurons, immunohistochemical assessments were performed for P2X3 receptor expression, isolectin B4 (IB4) binding, and substance P expression, three known injury-responsive markers in sensory neuronal subpopulations. In addition to examining the overall population of NG neurons, those innervating the urinary bladder also were assessed separately. All three of the molecular markers were represented in the NG from noninjured animals, with the majority of the neurons binding IB4. In the chronically injured rats, there was a significant increase in the number of NG neurons expressing P2X3 and a significant decrease in the number binding IB4 compared with noninjured animals, a finding that held true also for the bladder-innervating population. Overall, these results indicate that vagal afferents, including those innervating the bladder, display neurochemical plasticity post-SCI that may have implications for visceral homeostatic mechanisms and nociceptive signaling.

Towards multiple interactions of inner and outer sensations in corporeal awareness

Under normal circumstances, different inner- and outer-body sources are integrated to form coherent and accurate mental experiences of the state of the body, leading to the phenomenon of corporeal awareness. How these processes are affected by changes in inner and outer inputs to the body remains unclear. Here, we aim to present empirical evidence in which people with a massive sensory and motor disconnection may continue to experience feelings of general body state awareness without complete control of their inner and outer states. In these clinical populations, the activity of the neural structures subserving inner and outer body processing can be manipulated and tuned by means of body illusions that are usually based on multisensory stimulation. We suggest that a multisensory therapeutic approach could be adopted in the context of therapies for patients suffering from deafferentation and deefferentation. In this way, these individuals could regain a more complete feeling and control of the sensations they experience, which vary widely depending on their neurological condition.

Safety and neurological assessments after autologous transplantation of bone marrow mesenchymal stem cells in subjects with chronic spinal cord injury

Introduction

The administration of stem cells holds promise as a potential therapy for spinal cord injury (SCI). Mesenchymal stem cells have advantages for clinical applications, since they can be easily obtained, are suitable for autologous transplantation and have been previously shown to induce regeneration of the spinal cord in experimental settings. Here we evaluated the feasibility, safety and potential efficacy of autologous transplantation of mesenchymal stem cells in subjects with chronic complete SCI.

Method

We conducted a phase I, non-controlled study in 14 subjects of both genders aging between 18 to 65 years, with chronic traumatic SCI (>6 months), at thoracic or lumbar levels, classified as American Spinal Injury Association (ASIA) A - complete injury. Baseline somatosensory evoked potentials (SSEP), spinal magnetic resonance imaging (MRI) and urodynamics were assessed before and after treatment. Pain rating was performed using the McGill Pain Questionnaire and a visual analogue score scale. Bone marrow-derived mesenchymal stem cells were cultured and characterized by flow cytometry, cell differentiation assays and G-band karyotyping. Mesenchymal stem cells were injected directly into the lesion following laminectomy and durotomy.

Results

Cell transplantation was an overall safe and well-tolerated procedure. All subjects displayed variable improvements in tactile sensitivity and eight subjects developed lower limbs motor functional gains, principally in the hip flexors. Seven subjects presented sacral sparing and improved American Spinal Injury Association impairment scale (AIS) grades to B or C – incomplete injury. Nine subjects had improvements in urologic function. One subject presented changes in SSEP 3 and 6 months after mesenchymal stem cells transplantation. Statistically significant correlations between the improvements in neurological function and both injury size and level were found.

Conclusion

Intralesional transplantation of autologous mesenchymal stem cells in subjects with chronic, complete spinal cord injury is safe, feasible, and may promote neurological improvements.

Trial registration

ClinicalTrials.gov NCT01325103 – Registered 28 March 2011

Identification of bladder and colon afferents in the nodose ganglia of male rats

The sensory neurons innervating the urinary bladder and distal colon project to similar regions of the central nervous system and often are affected simultaneously by various diseases and disorders, including spinal cord injury. Anatomical and physiological commonalities between the two organs involve the participation of shared spinally derived pathways, allowing mechanisms of communication between the bladder and colon. Prior electrophysiological data from our laboratory suggest that the bladder also may receive sensory innervation from a nonspinal source through the vagus nerve, which innervates the distal colon as well. The present study therefore aimed to determine whether anatomical evidence exists for vagal innervation of the male rat urinary bladder and to assess whether those vagal afferents also innervate the colon. Additionally, the relative contribution to bladder and colon sensory innervation of spinal and vagal sources was determined. By using lipophilic tracers, neurons that innervated the bladder and colon in both the nodose ganglia (NG) and L6/S1 and L1/L2 dorsal root ganglia (DRG) were quantified. Some single vagal and spinal neurons provided dual innervation to both organs. The proportions of NG afferents labeled from the bladder did not differ from spinal afferents labeled from the bladder when considering the collective population of total neurons from either group. Our results demonstrate evidence for vagal innervation of the bladder and colon and suggest that dichotomizing vagal afferents may provide a neural mechanism for cross-talk between the organs.

Afferent pathways arising from the lower urinary tract after complete spinal cord injury or cauda equina lesion: clinical observations with neurophysiological implications

BACKGROUND

Afferents from the urinary tract transmit bladder sensations to the central nervous system. Spinal cord injury (SCI) may affect both efferent motor and afferent sensory pathways. Presence/absence of bladder sensations in patients with complete spinal cord, conus or cauda equina lesions was compared with neurologically unimpaired patients.

METHODS

During urodynamics, bladder sensations were studied and compared in 59 patients: 21 patients with complete SCI below T6 and above Th12, 7 patients with a complete lesion of the conus medullaris, 11 patients with a complete lesion of the cauda equina, and 20 patients without neurological deficit.

RESULTS

Two of 7 patients with complete conus lesion had a preserved filling sensation. Ten of 11 patients with complete lesion of the cauda equina reported a bladder filling sensation. Sensations are perceived at a similar pressure threshold but at a higher volume threshold.

CONCLUSIONS

In patients with a complete cauda or a lower conus lesion, a sensory input from the bladder is preserved. These findings imply that the preserved bladder filling sensation in complete cauda or lower conus lesions is possibly transferred through the intact hypogastric plexus to the thoracolumbar segments of the spinal cord.

The International Standards for Neurological Classification of Spinal Cord Injury: relationship between S4-5 dermatome testing and anorectal testing

STUDY DESIGN

Prospective cross-sectional multicenter study.

OBJECTIVE

To evaluate the correlation, sensitivity, specificity and predictive values of S4-5 dermatome and the anorectal examination for determination of sacral sparing in the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) examination.

SETTING

Two tertiary hospitals that specialize in pediatric spinal cord injuries.

METHODS

In all, 189 patients who were at minimum 3 month after spinal cord injury participated in complete ISNCSCI examinations. All examiners completed training for the proper completion of the ISNCSCI examination. Correlations and sensitivity/specificity analyses were conducted between S4-5 dermatome testing and the anorectal examination. Results were analyzed by age of patient, examiner, tetraplegia/paraplegia classification and injury level (T10-S3, L1-S3 and S3).

RESULTS

The correlation between S4-5 dermatome and anorectal sensation was moderate (0.62, P<0.001). Using the anorectal examination as the gold standard, the sensitivity of S4-5 testing was 0.60 (0.49, 70) and specificity was 0.96 (0.90, 0.99). No single age group, tester, level, or type of injury differed from the overall result.

CONCLUSION

In the pediatric population, the correlation between S4-5 and anorectal sensation was lower than anticipated. The sensitivity of 0.62 for S4-5 testing and diminished sensation between T10 and S3 suggests that anorectal testing may either be a more sensitive representation of S4-5 function or activate an alternative neuronal pathway that is perceived by the patient. Further investigation into the validity of the sacral sparing components of the ISNCSCI examination is warranted.

Efficacy of combined oral-intravesical oxybutynin hydrochloride treatment for patients with overactive detrusors and indwelling urethral catheters

The purpose of this article is to investigate the efficacy of intravesical oxybutynin hydrochloride (OH) to treat patients with overactive detrusors who are unresponsive to oral anticholinergic therapy alone. Twenty-five patients who were treated with oral OH for overactive detrusor (but who did not respond to treatment and were using indwelling urethral catheters) were given intravesical OH without changing oral treatment. Pre- and posttreatment bladder capacities were compared in urodynamic studies. The study showed that positive clinical results can be achieved with combined oral and intravesical OH treatments in patients with overactive detrusors who had indwelling urethral catheters because of severely reduced bladder capacity. However, a significant number of patients discontinued this treatment because of infection and difficulty in performing the procedure. Clinicians and rehabilitation nurses should provide education and support to eliminate these problems. In addition, the development of single-use standard sterile OH preparations for intravesical applications may increase the efficacy of the method.

Limited value of bladder sensation as a trigger for conditional neurostimulation in spinal cord injury patients

AIMS

Conditional stimulation of dorsal genital nerves suppresses undesired detrusor contractions (UDC) and consequently increases bladder capacity and prevents incontinence. No clinically applicable sensor exists for reliable bladder activity monitoring as a trigger for conditional stimulation. Primary objective of this study was to determine whether bladder sensation concomitant with UDC may be used for spinal cord injury (SCI) patients to trigger neurostimulation in daily life.

METHODS

Nineteen male and 7 female SCI patients suspected of detrusor overactivity (DO) underwent conventional and 6-hr ambulatory urodynamics. Patients were instructed to do normal daily activities and to activate event buttons of the ambulatory recorder to mark events: physical activity, bladder sensation, micturition or intermittent catheterization, and urinary incontinence. Detection rate was defined as the number of recorded bladder sensation divided by the total number of recorded UDC during ambulatory urodynamics.

RESULTS

Bladder sensation was reported by 73% of patients in daily life. Only 41% of patients had analyzable bladder sensation concomitant with UDC during ambulatory urodynamics. For ambulatory and conventional urodynamics, mean detection rates were 23% and 72%, respectively, with mean recording delays of 57 and 16 sec after UDC onset, respectively.

CONCLUSIONS

Bladder sensation only occurs in a small group of SCI patients combined with a rather low detection rate and long reaction time. Therefore, bladder sensation as a trigger for conditional stimulation does not seem to be suitable for SCI patients with DO. Reliable techniques for chronic bladder activity monitoring are a prerequisite for successful clinical application of conditional stimulation.

Cortical processing of residual ano-rectal sensation in patients with spinal cord injury: an fMRI study

Eleven paraplegic patients with complete traumatic spinal cord injuries (SCI) [according to American Spinal Injury Association (ASIA) criteria] at different levels (Th3-L3) were investigated during non-painful stimulation of the distal rectum and anal canal, using event related functional magnetic resonance imaging. Although a complete lesion was clinically diagnosed in all, four of them experienced reproducible sensations during anal and/or rectal stimulation. In six patients, individual data analysis revealed significant activation in the right secondary somatosensory cortex SII, the posterior cingular gyrus, the prefrontal cortex, and the left posterior cerebellar lobe during either anal or rectal stimulation or both. A Region of interest analysis using a data mask from healthy controls confirmed that SCI patients demonstrate cortical activation in areas similar to those activated in healthy volunteers, but to a less extensive degree. This supports the notion that the diagnosis of complete spinal cord transsection by ASIA criteria alone may be insufficient for assessment of 'completeness' of cord lesions, and that visceral sensitivity testing may be required in addition.

Urinary bladder irritation alters efficacy of vagal stimulation on rostral medullary neurons in chronic T8 spinalized rats

The presence of pelvic visceral inputs to neurons in the rostral medulla that are responsive to electrical stimulation of the abdominal branches of the vagus nerve (VAG-abd) was investigated in a complete chronic T8 spinal transection rat model. Using extracellular electrophysiological recordings from single medullary reticular formation (MRF) neurons, 371 neurons in 15 rats responsive to pinching the ear (search stimulus) were tested for somato-visceral and viscero-visceral convergent responses to stimulation of the following nerves/territories: VAG-abd, dorsal nerve of the penis, pelvic nerve, distention of urinary bladder and colon, penile stimulation, urethral infusion, and touch/pinch of the entire body surface. In addition to these mechanical and electrical stimuli, a chemical stimulus applied to the bladder was assessed as well. Of the total neurons examined, 205 were tested before and 166 tested beginning 20 min after application of a chemical irritant (2% acetic acid) to the urinary bladder (same rats used pre/post irritation). As with intact controls, many ear-responsive MRF neurons responded to the electrical stimulation of VAG-abd. Although MRF neuron responses failed to be evoked with direct (mechanical and electrical nerve) pelvic visceral stimuli, acute chemical irritation of the urinary bladder produced a significant increase in the number of MRF neurons responsive to stimulation of VAG-abd. The results of this study indicate a central effect that potentially relates to some of the generalized below level pelvic visceral sensations that have been documented in patients with complete spinal cord injury.

The determination of sensation-dependent bladder emptying time in patients with complete spinal cord injury above T11

STUDY DESIGN

Retrospective investigation using urodynamic studies and medical records.

OBJECTIVE

To evaluate the safety of sensation-dependent bladder emptying in complete spinal cord injury (SCI) patients, based on the preservation of the desire to void.

SETTING

Spinal Cord Injury Unit, Yonsei Rehabilitation Hospital, Seoul, Korea.

METHODS

This study was performed retrospectively on 79 complete SCI patients with lesions above T11, who had preserved the desire to void during conventional urodynamic studies. Patients were classified according to detrusor compliance and maximal bladder capacity. The clinical and urodynamic characteristics of each group were analyzed.

RESULTS

Forty-five (57.0%) patients were classified as group A and 34 (43.0%) patients were classified as group B. There were no significant differences in clinical features, such as voiding methods and the presence of autonomic dysreflexia between the two groups. Compared with group B, there were significantly more areflexic neurogenic bladder cases in group A (P<0.05). There were significantly higher maximal detrusor pressures in group B (P<0.05). There were significantly more cases with the preservation of the strong desire to void in group B (P<0.05).

CONCLUSION

Not all patients with discomplete SCIs accepted the use of sensation-dependent bladder emptying. The safe use of sensation-dependent bladder emptying will be determined based on the results of urodynamic studies.