Permanent sacral nerve stimulation for treatment of idiopathic constipation

Diagnostic and therapeutic approach to children with chronic refractory constipation: Consensus report by the SIGENP motility working group

Constipation is a common problem in children, accounting for about 3% of all primary care visits and up to 25% of referrals to paediatric gastroenterologists. Although polyethylene glycol often proves effective, most children require prolonged treatment and about 50% of them have at least one relapse within the first 5 years after initial recovery. When conventional treatment fails, children are considered to have refractory constipation. Children with refractory constipation deserve specialist management and guidance. Over the last decades, there has been a remarkable increase in our knowledge of normal and abnormal colonic and anorectal motility in children, and a number of different techniques to measure transit and motility have been developed. The present review analyses the possible diagnostic investigations for children with refractory constipation, focusing on their actual indications and their utility in clinical practice. Moreover, we have also analytically reviewed medical and surgical therapeutic options, which should be considered in selected patients in order to achieve the best clinical outcome.

Sacral Neuromodulation for defecation disorders after non oncologic pelvic surgery

PURPOSE

Defecation disorders (DD) can sometimes affect the outcomes of pelvic or colorectal surgery. The aim of the present study is to evaluate the role of sacral neuromodulation for the treatment of constipation and other evacuation disorders after surgery.

METHODS

A retrospective analysis in all the consecutive patients that underwent sacral nerve modulation (SNM) for DD arisen or worsened after pelvic or colorectal surgery was performed from January 2010 to December 2020. DD were defined starting from Rome IV Criteria, and according to manometric results, all patients were further divided into the two subgroups: inadequate defecatory propulsion and dyssynergic defecation. Cleveland Clinic Constipations Score (CCCS) and SF-36 have been evaluated in the time.

RESULTS

Thirty-seven patients have been included in the study. Twenty-seven out of thirty-seven (73.3%) patients had experienced sufficient benefits to implant the definitive device, and 22 patients (59.4% of tested and 81.5% of permanently implanted) still had the device functioning after a mean follow-up of 6.3 years. The most represented manometric pattern was inadequate propulsive function (59% of patients). CCCS at preoperative assessment for all patients was 17.5 with a reduction to 10.4 at the first year of follow-up (p < 0.001).

CONCLUSION

SNM appears to be a feasible, safe, and well-tolerated procedure with durable benefit in the long-term treatment of defecatory dysfunction after pelvic or colorectal surgery for benign diseases.

[Sacral Neuromodulation for Fecal Incontinence and Constipation: Evidence, Programming and Long-term Management]

BACKGROUND

Over the last two decades, sacral neuromodulation (SNM) has established its role in the treatment of functional pelvic organ-/pelvic floor disorders. Even though the mode of action is not fully understood, SNM has become the preferred surgical treatment of fecal incontinence.

METHODS AND RESULTS

A literature search was carried out on programming sacral neuromodulation and long-term outcomes in treating fecal incontinence and constipation.Sacral neuromodulation was found to be successful in the long term. Over the years, the spectrum of indications has expanded, and now includes patients presenting with anal sphincter lesions. The use of SNM for low anterior resection syndrome (LARS) is currently under clinical investigation. Findings of SNM for constipation are less convincing. In several randomised crossover studies, no success was demonstrated, even though it is possible that subgroups may benefit from the treatment. Currently the application cannot be recommended in general.The pulse generator programming sets the electrode configuration, amplitude, pulse frequency and pulse width. Usually pulse frequency and pulse width follow a default setting (14 Hz, 210 s), while electrode configuration and stimulation amplitude are adjusted individually to the patient need and perception of stimulation.Despite low infection rates and few electrode-/pulse generator dysfunctions, up to 65% of patients require surgical reintervention during long term follow-up - in 50% of cases because of battery depletion, which is an expected event. At least one reprogramming is necessary in about 75% of the patients during the course of the treatment, mostly because of changes in effectiveness, but rarely because of pain. Regular follow-up visits appear to be advisable.

CONCLUSION

Sacral neuromodulation can be considered to be a safe and effective long-term therapy of fecal incontinence. To optimise the therapeutic effect, a structured follow-up regime is advisable.

Ameliorating effects and mechanisms of transcutaneous auricular vagal nerve stimulation on abdominal pain and constipation

BackgroundAbdominal pain and constipation are 2 main symptoms in patients with constipation-predominant irritable bowel syndrome (IBS-C). This study aimed to investigate the effects and possible mechanisms of transcutaneous auricular vagal nerve stimulation (taVNS) in patients with IBS-C.MethodsForty-two patients with IBS-C were randomized into a 4-week sham-taVNS or taVNS treatment. The primary outcomes were complete spontaneous bowel movements per week (CSBMs/week) and visual analog scale (VAS) for abdominal pain. High-resolution anorectal manometry (HRAM) was performed to evaluate anorectal motor and sensory function. Cytokines and brain gut peptides were analyzed in blood samples. ECG was recorded for the assessment of autonomic function.ResultsCompared with sham-taVNS, (a) taVNS increased CSBMs/week (P = 0.001) and decreased VAS pain score (P = 0.001); (b) improved quality of life (P = 0.020) and decreased IBS symptom score (P = 0.001); (c) improved rectoanal inhibitory reflex (P = 0.014) and improved rectal sensation (P < 0.04); (d) decreased a number of proinflammatory cytokines and serotonin in circulation; and (e) enhanced vagal activity (P = 0.040). The vagal activity was weakly correlated with the CSBMs/week (r = 0.391; P = 0.010) and the VAS pain score (r = -0.347; P = 0.025).ConclusionsNoninvasive taVNS improves both constipation and abdominal pain in patients with IBS-C. The improvement in IBS-C symptoms might be attributed to the integrative effects of taVNS on intestinal functions mediated via the autoimmune mechanisms.Trial registrationwww.chictr.org.cn, no. ChiCTR2000029644.FundingNational Natural Science Foundation of China (grant no. 81970538 for FL).

The role of neuromodulation in chronic functional constipation: a systematic review

BACKGROUND

Chronic functional constipation is a highly prevalent disorder in which, when conservative measures fail to relieve symptoms, surgical interventions are sometimes indicated. In recent years, neuromodulation for the treatment of functional constipation has gained interest but its role and effectiveness are still unclear. The purpose of this review is to provide a systematic overview on the current literature on the different modalities of neurostimulation and their effect on chronic functional constipation in adults as reported in the literature.

METHODS

A search in the literature for articles concerning the effect of different types of neuromodulation on constipation was performed in PubMed using extensive search terms for the different modalities of neuromodulation. Studies and trials were checked for eligibility. For all types of neuromodulation together, 27 articles were included.

RESULTS

17 studies were included on SNM (sacral nerve modulation). Although multiple studies show positive results on the effect of SNM in constipation, double-blind crossover RCT's (randomised controlled trials) showed no significant effect. 3 studies were included for tSNS (transcutaneous sacral nerve stimulation), 2 for PTNS (percutaneous tibial nerve stimulation) and 2 for TTNS (transcutaneous tibial nerve stimulation). Studies and trials on these modalities of neuromodulation reported ambiguous results on statistical significance of the effect. For transcutaneous IFC (interferential current therapy) 2 studies were included, which both reported a statistically significant effect on all outcomes.

CONCLUSION

The beneficial effect of neuromodulation in chronic functional constipation remains questionable. However, neuro-modulation might be worth considering in patients refractory to treatment before turning to more invasive measures. Future research should shed more light on the effects of neuromodulation in constipation.

Heterogeneous outcome reporting in adult slow-transit constipation studies: Systematic review towards a core outcome set

BACKGROUND AND AIM

Standardizing evaluative outcomes and their assessment facilitates comparisons between clinical studies and provides a basis for comparing direct effects of different treatment options. The aim of this study was to systematically review types of outcomes and measurement instruments used in studies regarding treatment options for slow-transit constipation (STC) in adults.

METHODS

In this systematic review of the literature, we searched MEDLINE, Embase, and PsycINFO from inception through February 2018, for papers assessing any STC treatment in adult patients. Outcomes were systematically extracted and categorized in domains using the conceptual framework of the Outcome Measures in Rheumatology filter 2.0. Outcome reporting was stratified by decade of publication, intervention, and study type.

RESULTS

Forty-seven studies were included in this systematic review. Fifty-nine different types of outcomes were identified. The outcomes were structured in three core areas and 18 domains. The most commonly reported domains were defecation functions (94%), gastrointestinal transit (53%), and health-care service use (51%). The most frequently reported outcomes were defecation frequency (83%), health-related quality of life (43%), and adverse events and complications (43%). In 62% of the studies, no primary outcome was defined, whereas in two studies, more than one primary outcomes were selected. A wide diversity of measurement instruments was used to assess the reported outcomes.

CONCLUSION

Outcomes reported in studies on STC in adults are heterogeneous. A lack of standardization complicates comparisons between studies. Developing a core outcome set for STC in adults could contribute to standardization of outcome reporting in (future) studies.

Management of functional constipation in children and adults

Functional constipation is common in children and adults worldwide. Functional constipation shows similarities in children and adults, but important differences also exist regarding epidemiology, symptomatology, pathophysiology, diagnostic workup and therapeutic management. In children, the approach focuses on the behavioural nature of the disorder and the initial therapeutic steps involve toilet training and laxatives. In adults, management focuses on excluding an underlying cause and differentiating between different subtypes of functional constipation - normal transit, slow transit or an evacuation disorder - which has important therapeutic consequences. Treatment of adult functional constipation involves lifestyle interventions, pelvic floor interventions (in the presence of a rectal evacuation disorder) and pharmacological therapy. When conventional treatments fail, children and adults are considered to have intractable functional constipation, a troublesome and distressing condition. Intractable constipation is managed with a stepwise approach and in rare cases requires surgical interventions such as antegrade continence enemas in children or colectomy procedures for adults. New drugs, including prokinetic and prosecretory agents, and surgical strategies, such as sacral nerve stimulation, have the potential to improve the management of children and adults with intractable functional constipation.

An intravital window to image the colon in real time

Intravital microscopy is a powerful technique to observe dynamic processes with single-cell resolution in live animals. No intravital window has been developed for imaging the colon due to its anatomic location and motility, although the colon is a key organ where the majority of microbiota reside and common diseases such as inflammatory bowel disease, functional gastrointestinal disorders, and colon cancer occur. Here we describe an intravital murine colonic window with a stabilizing ferromagnetic scaffold for chronic imaging, minimizing motion artifacts while maximizing long-term survival by preventing colonic obstruction. Using this setup, we image fluorescently-labeled stem cells, bacteria, and immune cells in live animal colons. Furthermore, we image nerve activity via calcium imaging in real time to demonstrate that electrical sacral nerve stimulation can activate colonic enteric neurons. The simple implantable apparatus enables visualization of live processes in the colon, which will open the window to a broad range of studies.

Performing intravital imaging of the colon in mouse models is challenging due to the colon’s anatomic location and motility. Here, the authors develop a murine colonic window for intravital chronic imaging that maximises long-term animal survival and minimises motion artefacts.

Long-term outcome of intractable constipation treated by sacral neuromodulation: a comparison between children and adults

AIM

Sacral neuromodulation (SNM) is a minimally invasive therapy for functional constipation (FC) and is most often used to treat adults. Recent studies suggest that SNM may also beneficial in children. However, comparative data regarding preferred age of SNM for FC are lacking. Therefore, long-term results of SNM for FC were compared between children and adults.

METHOD

All patients treated with SNM for FC between 2004 and 2015 were evaluated. Outcomes of children (age 10-18 years) were compared with those for adults (≥ 18 years). The primary end-point was a defaecation frequency of three or more times per week, which is consistent with the ROME-III criteria. Secondary outcomes were quality of life (QoL; SF-36) and the Cleveland Clinic Constipation Score.

RESULTS

One hundred and eighty patients (45 children, 135 adults) were eligible for SNM. The mean age was 15.8 (children) and 41.4 years (adults). One hundred and twenty-six patients received permanent SNM (38 children, 88 adults). Mean follow-up was 47 months in both groups. Defaecation frequency increased in both groups after SNM compared with baseline. Defaecation frequency in adults was higher than in children. The increased defaecation frequency was maintained during the entire follow-up period in both groups. QoL of children was impaired compared with the Dutch population with regard to bodily pain, general health and vitality. Adults had worse QoL with regard to physical functioning, bodily pain, general health, vitality and social functioning compared with the Dutch population. QoL of children did not differ from adults.

CONCLUSION

Sacral neuromodulation (SNM) should be considered in children (< 18 years) with FC. However, the indication of SNM for FC remains debatable considering the limited improvements and high costs.

Surgery for constipation: systematic review and practice recommendations: Results V: Sacral Nerve Stimulation

AIM

To assess the outcomes of sacral nerve stimulation in adults with chronic constipation.

METHOD

Standardised methods and reporting of benefits and harms were used for all CapaCiTY reviews that closely adhered to PRISMA 2016 guidance. Main conclusions were presented as summary evidence statements with a summative Oxford Centre for Evidence-Based Medicine (2009) level.

RESULTS

Seven articles were identified, providing data on outcomes in 375 patients. Length of procedures and length of stay was not reported. Data on harms were inconsistently reported and heterogeneous, making estimates of harm tentative and imprecise. Morbidity rates ranged between 13 and 34%, with overall device removal rate between 8 and 23%. Although inconsistently reported, pooled treatment success was typically 57-87% for patients receiving permanent implants, although there was significant variation between studies. Patient selection was inconsistently documented. No conclusions could be drawn regarding particular phenotypes that responded favourably or unfavourably to sacral nerve stimulation.

CONCLUSION

Evidence supporting sacral nerve stimulation is derived from poor quality studies. Three methodologically robust trials are have reported since this review and all have all urged greater caution.

Long-term outcome of sacral neuromodulation for chronic refractory constipation

Purpose

Sacral neuromodulation has been reported as a treatment for severe idiopathic constipation. This study aimed to evaluate the long-term effects of sacral neuromodulation by following patients who participated in a prospective, open-label, multicentre study up to 5 years.

Methods

Patients were followed up at 1, 3, 6, 12, 24, 36, 48 and 60 months. Symptoms and quality of life were assessed using bowel diary, the Cleveland Clinic constipation score and the Short Form-36 quality-of-life scale.

Results

Sixty-two patients (7 male, median age 40 years) underwent test stimulation, and 45 proceeded to permanent implantation. Twenty-seven patients exited the study (7 withdrawn consent, 7 loss of efficacy, 6 site-specific reasons, 4 withdrew other reasons, 2 lost to follow-up, 1 prior to follow-up). Eighteen patients (29%) attended 60-month follow-up. In 10 patients who submitted bowel diary, their improvement of symptoms was sustained: the number of defecations per week (4.1 ± 3.7 vs 8.1 ± 3.4, mean ± standard deviation, p < 0.001, baseline vs 60 months) and sensation of incomplete emptying (0.8 ± 0.3 vs 0.2 ± 0.1, p = 0.002). In 14 patients (23%) with Cleveland Clinic constipation score, improvement was sustained at 60 months [17.9 ± 4.4 (baseline) to 10.4 ± 4.1, p < 0.001]. Some 103 device-related adverse events were reported in 27 (61%).

Conclusion

Benefit from sacral neuromodulation in the long-term was observed in a small minority of patients with intractable constipation. The results should be interpreted with caution given the high dropout and complication rate during the follow-up period.

Sacral Nerve Stimulation Fails to Offer Long-term Benefit in Patients With Slow-Transit Constipation

BACKGROUND

Sacral nerve stimulation is proposed as a treatment for slow-transit constipation. However, in our randomized controlled trial we found no therapeutic benefit over sham stimulation. These patients have now been followed-up over a long-term period.

OBJECTIVE

The purpose of this study was to assess the long-term efficacy of sacral nerve stimulation in patients with scintigraphically confirmed slow-transit constipation.

DESIGN

This study was designed for long-term follow-up of patients after completion of a randomized controlled trial.

SETTINGS

It was conducted at an academic tertiary public hospital in Sydney.

PATIENTS

Adults with slow-transit constipation were included.

MAIN OUTCOME MEASURES

At the 1- and 2-year postrandomized controlled trial, the primary treatment outcome measure was the proportion of patients who reported a feeling of complete evacuation on >2 days per week for ≥2 of 3 weeks during stool diary assessment. Secondary outcome was demonstration of improved colonic transit at 1 year.

RESULTS

Fifty-three patients entered long-term follow-up, and 1 patient died. Patient dissatisfaction or serious adverse events resulted in 44 patients withdrawing from the study because of treatment failure by the end of the second year. At 1 and 2 years, 10 (OR = 18.8% (95% CI, 8.3% to 29.3%)) and 3 patients (OR = 5.7% (95% CI, -0.5% to 11.9%)) met the primary outcome measure. Colonic isotope retention at 72 hours did not differ between baseline (OR = 75.6% (95% CI, 65.7%-85.6%)) and 1-year follow-up (OR = 61.7% (95% CI, 47.8%-75.6%)).

LIMITATIONS

This study only assessed patients with slow-transit constipation.

CONCLUSIONS

In these patients with slow-transit constipation, sacral nerve stimulation was not an effective treatment.

Bilateral transcutaneous tibial nerve stimulation for chronic constipation

AIM

Chronic constipation is difficult to treat when symptoms are intractable. Colonic propulsion may be altered by distal neuromodulation but this is conventionally delivered percutaneously. Transcutaneous tibial nerve stimulation is noninvasive and cheap: this study aimed to assess its efficacy in chronic constipation.

METHOD

Eighteen patients (median age 46 years, 12 female) with chronic constipation were recruited consecutively. Conservative and behavioural therapy had failed to improve symptoms in all 18. Thirty minutes of daily bilateral transcutaneous tibial nerve stimulation was administered by each patient at home for 6 weeks. The primary outcome measure was a change in the Patient Assessment of Constipation Quality of Life (PAC-QoL) score. Change in Patient Assessment of Constipation Symptoms (PAC-SYM), weekly bowel frequency and visual analogue scale (VAS) score were also measured.

RESULTS

Fifteen patients (12 female) completed the trial. The PAC-QoL score improved significantly with treatment [pretreatment, median 2.95, interquartile range (IQR) 1.18; posttreatment, median 2.50, IQR 0.70; P = 0.047]. There was no change in PAC-SYM score (pretreatment, median 2.36, IQR 1.59; posttreatment, median 2.08, IQR 0.92; P = 0.53). Weekly stool frequency improved as did VAS score, but these did not reach statistical significance (P = 0.229 and 0.161). The PAC-QoL and PAC-SYM scores both improved in four (26%) patients. Two patients reported complete cure. There were no adverse events reported.

CONCLUSION

Bilateral transcutaneous tibial nerve stimulation appears to be effective in a quarter of patients with chronic constipation. Carefully selected patients with less severe disease may benefit more. This requires further study.

Advancing treatment options for chronic idiopathic constipation

INTRODUCTION

Chronic constipation is a global problem affecting all ages and associated with considerable morbidity and significant financial burden for society. Though formerly defined on the basis of a single symptom, infrequent defecation; constipation is now viewed as a syndrome encompassing several complaints such as difficulty with defecation, a sense of incomplete evacuation, hard stools, abdominal discomfort and bloating.

AREAS COVERED

The expanded concept of constipation has inevitably led to a significant change in outcomes in clinical trials, as well as in patient expectations from new therapeutic interventions. The past decades have also witnessed a proliferation in therapeutic targets for new agents. Foremost among these have been novel prokinetics, a new category, prosecretory agents and innovative approaches such as inhibitors of bile salt transport. In contrast, relatively few effective therapies exist for the management of those anorectal and pelvic floor problems that result in difficult defecation.

EXPERT OPINION

Though constipation is a common and often troublesome disorder, many of those affected can resolve their symptoms with relatively simple measures. For those with more resistant symptoms a number of novel, effective and safe options now exist. Those with defecatory difficulty (anismus, pelvic floor dysfunction) continue to represent a significant management challenge.

Treatment efficacy of sacral nerve stimulation in slow transit constipation: a two-phase, double-blind randomized controlled crossover study

OBJECTIVES

Sacral nerve stimulation (SNS) is a potential treatment for constipation refractory to standard therapies. However, there have been no randomized controlled studies examining its efficacy. In patients with slow transit constipation, we evaluated the efficacy of suprasensory and subsensory SNS compared with sham, in a prospective, 18-week randomized, double-blind, placebo-controlled, two-phase crossover study. The primary outcome measure was the proportion of patients who, on more than 2 days/week for at least 2 of 3 weeks, reported a bowel movement associated with a feeling of complete evacuation.

METHODS

After 3 weeks of temporary peripheral nerve evaluation (PNE), all patients had permanent implantation and were randomized to subsensory/sham (3 weeks each) and then re-randomized to suprasensory/sham (3 weeks each) with a 2-week washout period between each arm. Daily stool dairies were kept, and quality of life (QoL; SF36) was measured at the end of each arm.

RESULTS

Between November 2006 and March 2012, 234 constipated patients were assessed, of whom 59 were willing and deemed eligible to participate (4 male; median age 42 years). Of the 59 patients, 16 (28%) responded to PNE. Fifty-five patients went on to permanent SNS implantation. The proportion of patients satisfying the primary outcome measure did not differ between suprasensory (30%) and sham (21%) stimulations, nor between subsensory (25%) and sham (25%) stimulations. There were no significant changes in QoL scores.

CONCLUSIONS

In patients with refractory slow transit constipation, SNS did not improve the frequency of complete bowel movements over the 3-week active period.

Long-term results following sacral nerve stimulation for chronic constipation

AIM

The long-term outcome of sacral nerve stimulation (SNS) for chronic functional constipation was assessed.

METHOD

Patients who received a definitive SNS implant for chronic functional constipation only (according to the Rome III criteria) and were followed up for at least 3 years were included in this study. Slow transit constipation (STC) was distinguished from obstructed defaecation (OD) and mixed/undetermined constipation (MU). Constipation features, Cleveland Clinic Constipation score (CCCS) and SF-36 questionnaire data were collected; physiological tests were performed.

RESULTS

Forty-two out of 61 patients suitable for SNS received a definitive implant (14 for STC, 15 for OD, 13 for MU). Following SNS device implantation (mean follow-up 51 ± 15 months), the baseline CCCS (17 ± 6) dropped to 9 ± 6 (P < 0.001) and 47% of patients had an improvement in the CCCS of more than 50%. Such improvement was more significant in patients with OD. Anal pressures did not change, while threshold and urgency rectal sensation significantly decreased, in particular in patients with OD. All aspects of patients' health status (SF-36) improved significantly following SNS; this was more marked in patients with OD.

CONCLUSION

Data from this study suggest that the clinical efficacy of SNS can be prolonged in constipated patients, but in both the preliminary diagnostic assessment and pathophysiological interpretation every effort should be made to select patients for SNS. Although SNS showed efficacy in a low percentage of patients with STC, patients with OD were more responsive.

Sacral nerve stimulation for faecal incontinence and constipation: a European consensus statement

AIM

In Europe during the last decade sacral nerve stimulation (SNS) or sacral neuromodulation (SNM) has been used to treat faecal incontinence (FI) and constipation. Despite this, there is little consensus on baseline investigations, patient selection and operative technique. A modified Delphi process was conducted to seek consensus on the current practice of SNS/SNM for FI and constipation.

METHOD

A systematic literature search of SNS for FI and constipation was conducted using PubMed. A set of questions derived from the search and expert opinion were answered on-line on two occasions by an international panel of specialists from Europe. A 1-day face-to-face meeting of the experts finalized the discussion.

RESULTS

Three hundred and ninety-three articles were identified from the literature search, of which 147 fulfilled the inclusion criteria. Twenty-two specialists in FI and constipation from Europe participated. Agreement was achieved on 43 (86%) of 50 domains including the set-up of service, patient selection, baseline investigations, operative technique and programming of the device. The median of agreement was 95% (35-100%).

CONCLUSION

Consensus was achieved on the majority of domains of SNS/SNM for FI and constipation. This should serve as a benchmark for safe and quality practice of SNS/SNM in Europe.

Electrical Stimulation and Motor Recovery

In recent years, several investigators have successfully regenerated axons in animal spinal cords without locomotor recovery. One explanation is that the animals were not trained to use the regenerated connections. Intensive locomotor training improves walking recovery after spinal cord injury (SCI) in people, and >90% of people with incomplete SCI recover walking with training. Although the optimal timing, duration, intensity, and type of locomotor training are still controversial, many investigators have reported beneficial effects of training on locomotor function. The mechanisms by which training improves recovery are not clear, but an attractive theory is available. In 1949, Donald Hebb proposed a famous rule that has been paraphrased as “neurons that fire together, wire together.” This rule provided a theoretical basis for a widely accepted theory that homosynaptic and heterosynaptic activity facilitate synaptic formation and consolidation. In addition, the lumbar spinal cord has a locomotor center, called the central pattern generator (CPG), which can be activated nonspecifically with electrical stimulation or neurotransmitters to produce walking. The CPG is an obvious target to reconnect after SCI. Stimulating motor cortex, spinal cord, or peripheral nerves can modulate lumbar spinal cord excitability. Motor cortex stimulation causes long-term changes in spinal reflexes and synapses, increases sprouting of the corticospinal tract, and restores skilled forelimb function in rats. Long used to treat chronic pain, motor cortex stimuli modify lumbar spinal network excitability and improve lower extremity motor scores in humans. Similarly, epidural spinal cord stimulation has long been used to treat pain and spasticity. Subthreshold epidural stimulation reduces the threshold for locomotor activity. In 2011, Harkema et al. reported lumbosacral epidural stimulation restores motor control in chronic motor complete patients. Peripheral nerve or functional electrical stimulation (FES) has long been used to activate sacral nerves to treat bladder and pelvic dysfunction and to augment motor function. In theory, FES should facilitate synaptic formation and motor recovery after regenerative therapies. Upcoming clinical trials provide unique opportunities to test the theory.

Transcutaneous Neuromodulation at Posterior Tibial Nerve and ST36 for Chronic Constipation

The aims of this study were to investigate the effects and possible mechanisms of transcutaneous neuromodulation (TN) in patients with chronic constipation. Twelve patients were recruited. The treatment consisted of 2-week TN and 2-week sham-TN which was performed in a crossover design. Bowel habit diary, Patient Assessment of Constipation Symptom (PAC-SYM), Patient Assessment of Constipation Quality of Life (PAC-QOL), and anorectal motility were evaluated. Electrocardiogram was recorded for the assessment of autonomic function during acute TN therapy. It was found that (1) TN improved the frequency of spontaneous defecation. After 2-week TN therapy, 83% patients had more than 3 times bowel movements per week which was significantly different from sham-TN (P = 0.01). (2) TN improved PAC-SYM and PAC-QOL scores (P < 0.001, resp.). (3) TN significantly decreased the threshold volume to elicit RAIR (P < 0.05), ameliorated rectal sensory threshold (P = 0.04), and maximum tolerance (P = 0.04). (4) TN, but not sham-TN, increased the vagal activity (P = 0.01 versus baseline) and decreased the sympathetic activity (P = 0.01, versus baseline). It was concluded that needleless TN at posterior tibial nerve and ST36 using a watch-size stimulator is effective in chronic constipation, and the effect was possibly mediated via the autonomic mechanism.

Sacral nerve stimulation changes rectal sensitivity and biomechanical properties in patients with irritable bowel syndrome

BACKGROUND

Sacral nerve stimulation (SNS) has been demonstrated to alleviate symptoms and improve quality of life in selected patients with irritable bowel syndrome (IBS). The mechanisms of action, however, remain unknown. The aim of the study was to evaluate the effects of SNS on rectal sensitivity and biomechanical properties in patients with IBS.

METHODS

Twenty patients with diarrhea-predominant (n = 11) or mixed (n = 9) IBS were treated with SNS in a controlled, randomized crossover trial. They were randomized to either 1 month of SNS (ON) or placebo (OFF) with the opposite setting for the next month. Sensory and biomechanical parameters were assessed by multimodal rectal stimulation at the end of each period. IBS-specific symptoms were evaluated at baseline and at the end of each treatment period.

KEY RESULTS

Cold stimuli were better tolerated in the ON period (19.9 °C[± 0.6]) compared to the OFF period (21.8 °C[± 0.6]; p = 0.03). Significantly lower cross-sectional areas were needed to elicit sensory responses in the ON period (1545 mm(2) [± 95]) compared to the OFF period (1869 mm(2) [± 92]; p = 0.015). The association between reduced sensory threshold and improvement of constipation was of borderline significance (p = 0.05). Wall stiffness was significantly lower in the ON period (192 mmHg[± 10]) compared to the OFF period (234 mmHg[± 10]; p = 0.004). Reduced wall stiffness was significantly associated with improved overall GSRS-IBS symptom score (p = 0.01). Reduced sensory threshold to stretch (p = 0.02) and reduced wall stiffness (p < 0.001) were predictors of the GSRS-IBS symptom score.

CONCLUSIONS & INFERENCES

SNS for diarrhea-predominant and mixed IBS relaxes the rectal wall, while making it more sensitive to stretch and less sensitive to cold. Reduced wall stiffness and increased sensitivity to stretch are associated with improved GSRS-IBS symptom score.

A systematic review of sacral nerve stimulation mechanisms in the treatment of fecal incontinence and constipation

BACKGROUND

Sacral nerve stimulation (SNS) is now well established as a treatment for fecal incontinence (FI) resistant to conservative measures and may also have utility in the management of chronic constipation; however, mechanism of action is not fully understood. End organ effects of SNS have been studied in both clinical and experimental settings, but interpretation is difficult due to the multitude of techniques used and heterogeneity of reported findings. The aim of this study was to systematically review available evidence on the mechanisms of SNS in the treatment of FI and constipation.

METHODS

Two systematic reviews of the literature (performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses framework) were performed to identify manuscripts pertaining to (a) clinical and (b) physiological effects of SNS during the management of hindgut dysfunction.

KEY RESULTS

The clinical literature search revealed 161 articles, of which 53 were deemed suitable for analysis. The experimental literature search revealed 43 articles, of which nine were deemed suitable for analysis. These studies reported results of investigative techniques examining changes in cortical, gastrointestinal, colonic, rectal, and anal function.

CONCLUSIONS & INFERENCES

The initial hypothesis that the mechanism of SNS was primarily peripheral motor neurostimulation is not supported by the majority of recent studies. Due to the large body of evidence demonstrating effects outside of the anorectum, it appears likely that the influence of SNS on anorectal function occurs at a pelvic afferent or central level.

Functional outcome after anal sphincter injury and treatment with mesenchymal stem cells

This research demonstrates the regenerative effects of mesenchymal stem cells (MSCs) on the injured anal sphincter by comparing anal sphincter pressures following intramuscular and serial intravascular MSC infusion in a rat model of anal sphincter injury. Fifty rats were divided into injury (n = 35) and no injury (NI; n = 15) groups. Each group was further divided into i.m., serial i.v., or no-treatment (n = 5) groups and followed for 5 weeks. The injury consisted of an excision of 25% of the anal sphincter complex. Twenty-four hours after injury, 5 × 10(5) green fluorescent protein-labeled MSCs in 0.2 ml of phosphate-buffered saline (PBS) or PBS alone (sham) were injected into the anal sphincter for i.m. treatment; i.v. and sham i.v. treatments were delivered daily for 6 consecutive days via the tail vein. Anal pressures were recorded before injury and 10 days and 5 weeks after treatment. Ten days after i.m. MSC treatment, resting and peak pressures were significantly increased compared with those in sham i.m. treatment (p < .001). When compared with the NI group, the injury groups had anal pressures that were not significantly different 5 weeks after i.m./i.v. treatment. Both resting and peak pressures were also significantly increased after i.m./i.v. MSC treatment compared with treatment with PBS (p < .001), suggesting recovery. Statistical analysis was done using paired t test with Bonferroni correction. Marked decrease in fibrosis and scar tissue was seen in both MSC-treated groups. Both i.m. and i.v. MSC treatment after injury caused an increase in anal pressures sustained at 5 weeks, although fewer cells were injected i.m. The MSC-treated groups showed less scarring than the PBS-treated groups, with the i.v. infusion group showing the least scarring.

Sacral nerve stimulation: Interstim®therapy

Sacral nerve stimulation is a young but promising technique in the treatment of chronic voiding dysfunctions. Electrical stimulation of the S3 nerve--using a pacemaker device--is able to treat a wide range of pelvic floor dysfunctions. This article gives a brief review on the indications, mechanisms of action and possible complications of this technique. Furthermore, new evolutions in the domain of sacral nerve modulation are discussed.

Review of sacral neuromodulation for management of constipation

BACKGROUND

Sacral neuromodulation (SN) is an emerging treatment for constipation. This review evaluates the mechanism of action, techniques, efficacy, and adverse effects of SN in the management of constipation.

METHODS

Electronic searches for studies describing the use of SN were performed in PubMed, MEDLINE and Embase. Abstracts were reviewed and full text copies of all relevant articles obtained.

RESULTS

Fifty-nine results were obtained on the initial searches. Ten studies discussed the results of SN in patients with constipation. A total of 225 temporary neuromodulations and 125 permanent implants were performed. Bowel diaries showed improvement in assessment criteria in more than 50% of patients on temporary neuromodulation and the results were maintained in approximately 90% of patients who underwent permanent implantation over medium to long-term follow-up. The rate of adverse effects was high, but the majority of them were related to electrode position. Improvements in transit studies and anorectal physiology after neuromodulation were noted in some studies. The recognized limitations included a lack of randomized studies and an inability to perform meta-analysis.

CONCLUSION

Sacral neuromodulation may be an effective treatment in selected patients with constipation and should be a part of the management repertoire. Improvement in defecatory frequency with temporary wire placement is a good predictor of subsequent response following permanent implant. Further research into predictive factors for success would improve patient selection.

Preoperative constipation is associated with poor prognosis of rectal cancer: a prospective cohort study

Purpose

It is unknown whether patients with advanced rectal cancer develop severe constipation. Therefore, the objective of this study was to assess whether constipation severity is associated with pathologic progression of rectal cancer.

Methods

We analyzed 472 patients with rectal cancer who underwent elective surgical resection between January 2005 and December 2010. Constipation severity was prospectively evaluated in 407 patients (86.2%) using the Cleveland Clinic Constipation Score System. Linear regression analysis was performed to identify clinicopathologic variables associated with constipation. Kaplan-Meier analysis and Cox proportional hazard models were used to evaluate the prognostic value of constipation severity on disease-free and overall survival.

Results

Multivariable analysis showed that sex (regression coefficient [B] = 1.55; 95% confidence interval [CI], 0.79 to 2.60; P < 0.001), body mass index (B = -0.95; 95% CI, -1.83 to -0.64; P = 0.036), tumor size (B = 1.04; 95% CI, 0.20 to 1.88; P = 0.016), T stage (B = 0.75; 95% CI, 0.23 to 1.27; P = 0.005), and distant metastasis (B = 1.16; 95% CI, 0.03 to 2.30; P = 0.045) were associated with constipation severity. Severe constipation (score ≥ 8) was independently associated with 3-year disease-free survival (vs. scores of 0-3; hazard ratio [HR], 2.39; 95% CI, 1.15 to 4.98; P = 0.020) and 5-year overall survival (HR, 2.30; 95% CI, 1.23 to 4.30; P = 0.009) in multivariable analysis.

Conclusion

Our results suggest that preoperative constipation severity is associated with advanced pathologic stage and poor oncologic outcomes in patients with rectal cancer.

Functional outcomes and quality of life in patients treated with laparoscopic total colectomy for colonic inertia

PURPOSE

To assess the functional outcomes and quality of life in patients with laparoscopic total colectomy for slow-transit constipation (STC).

METHODS

All patients undergoing laparoscopic colectomy with ileorectal anastomosis for colonic inertia at two referral centers were analyzed. Their preoperative, intraoperative and postoperative details were recorded with a one-year follow-up. Their quality of life was assessed using the SF-36 questionnaire.

RESULTS

Between 2004 and 2007, 710 patients were evaluated. Eight female patients (1.1 %) fulfilled the criteria for STC without obstructive defecation syndrome. Their mean age was 38 years ± 15 (range from 22 to 62). The conversion rate was 12.5 %. The morbidity rate was 37.5 %, and mortality was nil. The preoperative abdominal pain was 6.6 ± 0.3 and had decreased to 3.6 ± 2.3 postoperatively (P = 0.008). At 1 year, the defecation frequency per week had increased from 0.84 ± 0.24 to 6.75 ± 3.4 (P = 0.001). Three patients developed nocturnal leakage (37.5 %). Eighty-eight percent of the patients recommend the procedure. All parameters of the SF-36 questionnaire had improved at the one-year follow-up examination.

CONCLUSION

Laparoscopic colectomy for slow-transit constipation is safe and increased the number of evacuations per week. Although nocturnal leakage may occur, these patients experience improvements in their quality of life.

Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (part II: treatment)

The second part of the Consensus Statement of the Italian Association of Hospital Gastroenterologists and Italian Society of Colo-Rectal Surgery reports on the treatment of chronic constipation and obstructed defecation. There is no evidence that increasing fluid intake and physical activity can relieve the symptoms of chronic constipation. Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre. Osmotic laxatives may be effective in patients who do not respond to fibre supplements. Stimulant laxatives should be reserved for patients who do not respond to osmotic laxatives. Controlled trials have shown that serotoninergic enterokinetic agents, such as prucalopride, and prosecretory agents, such as lubiprostone, are effective in the treatment of patients with chronic constipation. Surgery is sometimes necessary. Total colectomy with ileorectostomy may be considered in patients with slow-transit constipation and inertia coli who are resistant to medical therapy and who do not have defecatory disorders, generalised motility disorders or psychological disorders. Randomised controlled trials have established the efficacy of rehabilitative treatment in dys-synergic defecation. Many surgical procedures may be used to treat obstructed defecation in patients with acquired anatomical defects, but none is considered to be the gold standard. Surgery should be reserved for selected patients with an impaired quality of life. Obstructed defecation is often associated with pelvic organ prolapse. Surgery with the placement of prostheses is replacing fascial surgery in the treatment of pelvic organ prolapse, but the efficacy and safety of such procedures have not yet been established.

Sacral neuromodulation for bowel dysfunction: a consensus statement from the Italian group

BACKGROUND

Representatives from the Italian centers experienced in sacral neuromodulation (SNM) for the treatment of bowel dysfunction met in order to define the current clinical practice in Italy and to produce a consensus statement regarding indications for this therapy and patient management.

METHODS

Fifty Italian colonproctologists were asked to complete a questionnaire concerning their clinical practice in SNM (290 questions, grouped within 4 broad areas). Physicians expressed their opinion by completing the questionnaire, assigning to each statement their level of agreement according to the 5-point Likert scale; the data were analyzed by attributing to each expert's answers a weight proportional to the degree of experience. During a meeting held 2 months later, the critical aspects of the therapy were re-examined and discussions held with the goal of reaching an agreement on controversial topics. The available literature was reviewed.

RESULTS

Patient selection criteria, etiology, diagnostic investigations, test procedures and implantation, follow-up and evaluation of results have been reviewed. The aim was to achieve an algorithm for patient management, showing the place of SNM in the treatment of bowel dysfunction. The approach in case of treatment failure was also discussed.

CONCLUSIONS

Analysis of the data collected reveals substantial consensus at the national level concerning all the main points with regard to the therapy. The recommendations expressed in this article can be considered as national guidelines and taken into account by the principal international implantation centers.

Sacral nerve stimulation for constipation

BACKGROUND

For over 10 years sacral nerve stimulation (SNS) has been used for patients with constipation resistant to conservative treatment. A review of the literature is presented.

METHODS

PubMed, MEDLINE and Embase databases were searched for studies demonstrating the use of SNS for the treatment of constipation.

RESULTS

Thirteen studies have been published describing the results of SNS for chronic constipation. Of these, three were in children and ten in adults. Test stimulation was successful in 42-100 per cent of patients. In those who proceeded to permanent SNS, up to 87 per cent showed an improvement in symptoms at a median follow-up of 28 months. The success of stimulation varied depending on the outcome measure being used. Symptom improvement correlated with improvement in quality of life and patient satisfaction scores.

CONCLUSION

SNS appears to be an effective treatment for constipation, but this needs to be confirmed in larger prospective studies with longer follow-up. Improved outcome measures need to be adopted given the multiple symptoms that constipation may be associated with. Comparison with other established surgical therapies also needs consideration.

Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (Part II: Treatment)

The second part of the Consensus Statement of the Italian Association of Hospital Gastroenterologists and Italian Society of Colo-Rectal Surgery reports on the treatment of chronic constipation and obstructed defecation. There is no evidence that increasing fluid intake and physical activity can relieve the symptoms of chronic constipation. Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre. Osmotic laxatives may be effective in patients who do not respond to fibre supplements. Stimulant laxatives should be reserved for patients who do not respond to osmotic laxatives. Controlled trials have shown that serotoninergic enterokinetic agents, such as prucalopride, and prosecretory agents, such as lubiprostone, are effective in the treatment of patients with chronic constipation. Surgery is sometimes necessary. Total colectomy with ileorectostomy may be considered in patients with slow-transit constipation and inertia coli who are resistant to medical therapy and who do not have defecatory disorders, generalised motility disorders or psychological disorders. Randomised controlled trials have established the efficacy of rehabilitative treatment in dys-synergic defecation. Many surgical procedures may be used to treat obstructed defecation in patients with acquired anatomical defects, but none is considered to be the gold standard. Surgery should be reserved for selected patients with an impaired quality of life. Obstructed defecation is often associated with pelvic organ prolapse. Surgery with the placement of prostheses is replacing fascial surgery in the treatment of pelvic organ prolapse, but the efficacy and safety of such procedures have not yet been established.

Consensus statement AIGO/SICCR diagnosis and treatment of chronic constipation and obstructed defecation (part II: treatment)

The second part of the Consensus Statement of the Italian Association of Hospital Gastroenterologists and Italian Society of Colo-Rectal Surgery reports on the treatment of chronic constipation and obstructed defecation. There is no evidence that increasing fluid intake and physical activity can relieve the symptoms of chronic constipation. Patients with normal-transit constipation should increase their fibre intake through their diet or with commercial fibre. Osmotic laxatives may be effective in patients who do not respond to fibre supplements. Stimulant laxatives should be reserved for patients who do not respond to osmotic laxatives. Controlled trials have shown that serotoninergic enterokinetic agents, such as prucalopride, and prosecretory agents, such as lubiprostone, are effective in the treatment of patients with chronic constipation. Surgery is sometimes necessary. Total colectomy with ileorectostomy may be considered in patients with slow-transit constipation and inertia coli who are resistant to medical therapy and who do not have defecatory disorders, generalised motility disorders or psychological disorders. Randomised controlled trials have established the efficacy of rehabilitative treatment in dys-synergic defecation. Many surgical procedures may be used to treat obstructed defecation in patients with acquired anatomical defects, but none is considered to be the gold standard. Surgery should be reserved for selected patients with an impaired quality of life. Obstructed defecation is often associated with pelvic organ prolapse. Surgery with the placement of prostheses is replacing fascial surgery in the treatment of pelvic organ prolapse, but the efficacy and safety of such procedures have not yet been established.

Practical treatments for constipation in Korea

Constipation is a digestive symptom that is frequently seen in clinical practice. Its prevalence has been reported to be 2% to 20%, depending on geographical region. Despite the rapid development of medical science, systematic studies on constipation have been rarely conducted in Korea. Recently, guidelines on the diagnosis and treatment of functional gastrointestinal disorders, including constipation, were proposed by The Korean Society of Neurogastroenterology and Motility. These guidelines are expected to reflect the current situation regarding treatment of constipation in Korea. In this paper, practical constipation treatment methods that are in current use will be reviewed with reference to these recent guidelines.

Pancolonic motor response to subsensory and suprasensory sacral nerve stimulation in patients with slow-transit constipation

BACKGROUND

Sacral nerve stimulation (SNS) is emerging as a potential treatment for patients with constipation. Although SNS can elicit an increase in colonic propagating sequences (PSs), the optimal stimulus parameters for this response remain unknown. This study evaluated the colonic motor response to subsensory and suprasensory SNS in patients with slow-transit constipation.

METHODS

Patients with confirmed slow-transit constipation were studied. Either a water-perfused manometry catheter or a high-resolution fibre-optic manometry catheter was positioned colonoscopically to the caecum. A temporary electrode was implanted transcutaneously in the S3 sacral nerve foramen. In the fasted state, three conditions were evaluated in a double-blind randomized fashion: sham, subsensory and suprasensory stimulation. Each 2-h treatment period was preceded by a 2-h basal period. The delta (Δ) value was calculated as the frequency of the event during stimulation minus that during the basal period.

RESULTS

Nine patients had readings taken with a water-perfused catheter and six with a fibre-optic catheter. Compared with sham stimulation, suprasensory stimulation caused a significant increase in the frequency of PSs (mean(s.d.) Δ value - 1·1(7·2) versus 6·1(4·0) PSs per 2 h; P = 0·004). No motor response was recorded in response to subsensory stimulation compared with sham stimulation. Compared with subsensory stimulation, stimulation at suprasensory levels caused a significant increase in the frequency of PSs (P = 0·006).

CONCLUSION

In patients with slow-transit constipation, suprasensory SNS increased the frequency of colonic PSs, whereas subsensory SNS stimulation did not. This has implications for the design of therapeutic trials and the clinical application of the device.

Sacral nerve modulation in the treatment of chronic pain after pelvic surgery

AIM

The aim of the study was to evaluate the efficacy of sacral nerve modulation for chronic pelvic pain after pelvic or anal surgery for benign disease.

METHOD

From January 2004 to December 2009, 17 (14 female; age 56 years) consecutive patients suffering from chronic pelvic pain underwent evaluation for sacral nerve modulation in three pelvic floor units.

RESULTS

The previous surgery included stapled transanal rectal resection (five), hysterectomy (four), haemorrhoidectomy (two), stapled haemorrhoidopexy (one), fistulectomy (one), urethral sphincterotomy (one), appendicectomy (one), discectomy (one) and laparoscopy for endometriosis (one). Eight (47%) patients fulfilled the criteria for definitive implantation and were followed for a mean of 39 months. Using a visual analog pain score, pain levels fell from 8.2 preoperatively to 1.9, 2.1, 2.0 and 1.8 at 6, 12, 24 and 36 months, respectively. Age < 60 years and duration of symptoms of < 24 months were good predictors and stapling was a poor predictor of success.

CONCLUSION

Sacral nerve modulation seems to be effective over time in some patients with chronic pain related to previous surgery.

Sacral neuromodulation therapy: a promising treatment for adolescents with refractory functional constipation

BACKGROUND

Sacral neuromodulation therapy has been successfully applied in adult patients with urinary and fecal incontinence and in adults with constipation not responding to intensive conservative treatment. No data, however, are available on sacral neuromodulation therapy as a treatment option in adolescents with refractory functional constipation.

OBJECTIVES

This study aimed to describe the short-term results of sacral neuromodulation in adolescents with chronic functional constipation refractory to intensive conservative treatment.

DESIGN

This is a retrospective review.

SETTING

This study took place at the Department of Surgery, Maastricht University Medical Centre, The Netherlands.

PATIENTS

Thirteen patients (all girls, age 10-18 years) with functional constipation according to the ROME III criteria not responding to intensive oral and rectal laxative treatment were assigned for sacral neuromodulation.

MAIN OUTCOME MEASURES

When improvement of symptoms was observed during the testing phase, a permanent stimulator was implanted. Patients were prospectively followed up to at least 6 months after implantation of the permanent stimulator by interviews, bowel diaries, and Cleveland Clinic constipation score. Improvement was defined as spontaneous defecation ≥ 2 times a week.

RESULTS

At presentation, none of the patients had spontaneous defecation or felt the urge to defecate. All patients had severe abdominal pain. Regular school absenteeism was present in 10 patients. After the testing phase, all but 2 patients had spontaneous defecation ≥ 2 times a week with a reduction in abdominal pain. After implantation, 11 (of 12) had a normal spontaneous defecation pattern of ≥ 2 times a week without medication, felt the urge to defecate, and perceived less abdominal pain without relapse of symptoms until 6 months after implantation. The average Cleveland Clinic constipation score decreased from 20.9 to 8.4. One lead revision and 2 pacemaker relocations were necessary.

LIMITATIONS

This study is limited by its small sample size, single-institution bias, and retrospective nature.

CONCLUSION

Sacral neuromodulation appears to be a promising new treatment option in adolescents with refractory functional constipation not responding to intensive conservative therapy. Larger randomized studies with long-term follow-up are required.

Medium-term outcome of sacral nerve modulation for constipation

BACKGROUND

Sacral nerve modulation has been reported as a minimally invasive and effective treatment for constipation refractory to conservative treatment.

OBJECTIVE

This study aimed to evaluate the efficacy and sustainability of sacral nerve modulation for constipation in the medium term (up to 6 years) and to investigate potential predictors of treatment success.

DESIGN

We performed a retrospective review of prospectively collected data.

SETTINGS

The study was performed at 2 tertiary-care centers in Europe with expertise in pelvic floor disorders and sacral nerve modulation.

PATIENTS

Patients were eligible if they had had symptoms of constipation persisting for at least 1 year, if conservative treatment (dietary modification, laxatives and biofeedback therapy) had failed, and if predefined excluded conditions were not present.

INTERVENTION

The first phase of the treatment process was percutaneous nerve evaluation. If this was successful, patients underwent sacral nerve modulation therapy with an implanted device (tined-lead and implantable pulse generator).

MAIN OUTCOME MEASURE

Follow-up was performed at 1, 3, 6, and 12 months, and yearly thereafter. Outcome was assessed with the Wexner constipation score.

RESULTS

A total of 117 patients (13 men, 104 women) with a mean age of 45.6 (SD, 13.0) years underwent percutaneous nerve evaluation. Of these, 68 patients (58%) had successful percutaneous nerve evaluation and underwent implantation of a device. The mean Wexner score was 17.0 (SD, 3.8) at baseline and 10.2 (SD 5.3) after percutaneous nerve evaluation (p < .001); the improvement was maintained throughout the follow-up period, although the number of patients continuing with sacral nerve modulation at the latest follow-up (median, 37 months; range, 4-92) was only 61 (52% of all patients who underwent percutaneous nerve evaluation). The sole predictive factor of outcome of percutaneous nerve evaluation was age: younger patients were more likely than older patients to have a successful percutaneous nerve evaluation phase.

LIMITATIONS

The study was limited by a lack of consistent outcome measures.

CONCLUSIONS

: Despite improvement in Wexner scores, at the latest follow-up sacral nerve modulation was only being used by slightly more than 50% of the patients who started the first phase of treatment. Further studies are needed to reassess the efficacy and sustainability of sacral nerve modulation.

Sacral neuromodulation for the management of severe constipation: development of a constipation treatment protocol

BACKGROUND

Constipation is a common multifactorial gastrointestinal symptom with quality of life implications. Sacral neuromodulation has been used in the management of severe constipation with mixed results. The aim of this study was to review our experience of sacral neuromodulation as a treatment for chronic constipation and develop a chronic constipation management protocol.

METHODS

In patients with severe constipation, failure of conservative management including biofeedback and rectal irrigation were considered for neuromodulation. Temporary stimulation lead was placed in the sacral foramen of eligible patients and pre and post stimulation bowel diaries were compared. Patients with ≥50% improvement in bowel diaries had permanent implant. Patients were followed up at 2 and 4 weeks, 3, 6, and 12 months, and then yearly with bowel diaries.

RESULTS

Temporary neuromodulation wires were implanted in 21 patients (20 female). Significant bowel diary improvement was seen in 12 (57%) patients (p < 0.01). Eleven permanent implants have been performed. Improvement in symptoms was lost in one patient. No major side effects were observed. Three patients have had reoperations (one wire fracture, one reposition of battery, and one poor initial lead placement). Improvements in bowel diaries have been maintained over a median follow-up period of 38 months (18-62 months).

CONCLUSION

Sacral neuromodulation can provide long-term symptom relief in selected patients with severe constipation. Sacral neuromodulation should be incorporated into the treatment algorithm for chronic constipation.

Postoperative issues of sacral nerve stimulation for fecal incontinence and constipation: a systematic literature review and treatment guideline

BACKGROUND

There is a lack of knowledge on the incidence and management of suboptimal therapeutic effect and the complications associated with sacral nerve stimulation for fecal incontinence and constipation.

OBJECTIVE

This study aimed to review current literature on postoperative issues and to propose a treatment algorithm.

DATA SOURCE

PubMed, MEDLINE, and EMBASE were searched using the keywords "sacral nerve stimulation," "sacral neuromodulation," "fecal incontinence," and "constipation" for English-language articles published from January 1980 to August 2010. A further search was conducted on a wider literature using the keywords "complication," "adverse effect," "treatment failure," "equipment failure," "infection," "foreign-body migration," "reoperation," "pain," and "algorithm."

STUDY SELECTION

Four hundred sixty-one titles were identified, and after a title and abstract review, 135 were subjected to full article review; 89 were finally included in this review. Five articles were added by manual search and consensus.

RESULTS

Forty-eight studies were identified as cohort studies reporting on postoperative issues, including 1661 patients who underwent percutaneous nerve evaluation and 1600 patients who proceeded to sacral nerve stimulation therapy. Pooled data showed that the most common problem during percutaneous nerve evaluation was lead displacement (5.3%). The incidence of suboptimal outcome, pain, and infection after implantation was 12.1%, 13.0%, and 3.9%.

LIMITATIONS

There was significant underreporting of untoward events, because 60% of the studies did not report complications during percutaneous nerve evaluation, and suboptimal outcome after implantation was not disclosed in 44% of the studies.

CONCLUSIONS

The incidence of untoward events associated with sacral nerve stimulation appears to be low. However, there is a significant underreporting of the incidence. Using the information from the structured and systematic literature review, we formulated a clinically relevant guideline for reporting and managing postoperative issues. The guideline can provide a framework for clinical practice.

Progress in understanding the role of neuromodulation in the pathogenesis of functional gastrointestinal disorders

Functional gastrointestinal disorders (FGIDs) are a group of common digestive diseases whose pathogenesis is closely related to the abnormal brain-gut axis. Disturbances of the neuromodulatory processes in the brain-gut axis generate functional digestive disorders mainly centered on the pain, bloating symptoms and motility diseases. This article reviews neuromodulatory mechanism aspects of the brain-gut axis and discusses the clinical prospects for the neuromodulatory interventional treatment of FGIDs.

[Guidelines for the treatment of constipation]

While constipation is a common symptom in Korea, there are no existing treatment guidelines. Although constipation may occur as a result of organic cause, there is no obstructive mucosal or structural cause in the vast majority of patients with constipation. The present paper deals with only the management of functional constipation: lifestyle changes; bulking agents and stool softeners; osmotic agents; stimulant laxatives; prokinetics; biofeedback and surgical treatments. Exercise and dietary fiber are helpful in some patients with constipation. Laxatives including bulking agents, stool softeners, osmotic agents, and stimulant laxatives have been found to be more effective than placebo at relieving symptoms of constipation. New enterokinetic agents that affect peristalsis through selective interaction with 5-hydroxytryptamine-4 receptors can be effective in patients with constipation who cannot get adequate relief from current laxatives. Biofeedback can relieve symptoms in selected patients with pelvic floor dyssynergia. Surgical treatments can be helpful in some patients with refractory constipation.

Status of sacral neuromodulation for refractory constipation

AIM

This review article aims to provide a brief update on the current data on and position of sacral neuromodulation (SNM) in the specialized management of refractory idiopathic constipation.

METHOD

Published evidence from PubMed and our own unpublished data on SNM treatment for refractory idiopathic constipation were used for this evaluation.

RESULTS

Seven studies were found in PubMed that covered this topic. The main focus was on the most recently published multicentre nonrandomized European trial. Summary data from our unpublished study on constipation in children are also included.

CONCLUSIONS

The use of SNM in the treatment of idiopathic constipation is still in its early phase and while the available efficacy and safety data are limited, they show promising results. As there are few alternatives for this difficult patient group, it is worth offering a percutaneous nerve evaluation (PNE) test, which is known to be a good predictor of postimplant treatment success.

Neuromodulation for constipation: sacral and transcutaneous stimulation

Constipation is a frequently occurring digestive ailment that is usually treated conservatively. Neuromodulation is altering function of an organ by altering neural activity. This paper reviews methods of neuromodulation used to treat constipation. This includes direct stimulation of sacral nerves and stimulation across the skin. Direct stimulation of sacral nerves is the most well developed method and is presented in detail. It is generally accepted that the mechanism of action is modulation rather than stimulation so it is called sacral neuromodulation (SNM). SNM involves percutaneous placement of an electrode in the third sacral foramen and implanting a stimulating device under the skin in the buttocks. SNM is founded on the physiological principle that activity in one neural pathway modulates pre-existing activity in another through synaptic interaction. The mechanism of action in constipation may be neuromodulation of the extrinsic neural control of the large bowel or modulation of reflexes inhibiting large bowel function. Limited evidence is available to assess the outcome of SNM in constipation. Results in the medium term seem promising for selected patients with idiopathic slow and normal transit constipation not responding to optimal conservative treatment. Adverse events include electrode migration and infection. The availability of a testing phase provides a predictor of treatment outcome. In addition, transcutaneous stimulation using sticky pad electrodes over the lumbosacral region or acupuncture points has been reported to improve constipation symptoms. In general, the level of evidence is low and further studies are needed.

Patient experience and satisfaction with sacral neuromodulation: results of a single-center sample survey

PURPOSE

Sacral neuromodulation is a well researched and successful treatment for functional bowel disorders. Indications have expanded throughout the years and various studies have been published on clinical efficacy or on technique improvement. The main goal of this retrospective study was to systematically evaluate daily experiences with this treatment and measure the long-term satisfaction of sacral neuromodulation therapy for functional bowel disorders.

METHODS

After institutional review board approval a new, self-designed postal questionnaire was sent to all patients in our center who were being treated with sacral neuromodulation. Only patients with a minimal follow-up of 1 year were included in the survey. Implantation years range from 2000 to 2007.

RESULTS

A total of 174 patients received the questionnaire regarding patient satisfaction and experience with sacral neuromodulation therapy. The response rate after reminder letter was 71.8% (n = 125) including 114 (91.2%) females. Patient satisfaction was high: 81 patients (65.3%) reported their results as very satisfying, 30 patients (24.2%) were moderately satisfied, and 13 patients (10.4%) were not satisfied. Analysis showed that patient satisfaction can be explained by both patient perception of present bowel function and their evaluation of the quality of daily life. No significant relationship was found with patient demographics, self-ascribed (co)morbidity, behavioral habits, or therapy duration. A total of 47 patients (38.2%) reported having some concerns regarding the future with sacral neuromodulation treatment. Twenty-eight patients (23.1%) reported a temporary loss of effect at any time during sacral neuromodulation therapy. Pain at the implantation site was reported by 65 patients (52.4%).

CONCLUSIONS

This study shows that patients treated with sacral neuromodulation, in general, are very satisfied. The main problems mentioned by patients are pain, loss of efficacy, and general concerns.

Treatment of slow-transit constipation with sacral nerve modulation

AIM

Constipation is common and a selection of the best treatment is difficult, especially for slow-transit constipation (STC). The aim of the study was to assess the effect of sacral nerve modulation (SNM) on STC.

METHOD

A retrospective analysis of patients with STC, treated with SNM was undertaken. All were evaluated by cinedefecography, colon transit-time, Cleveland Clinic Constipation Score (CCS), SF-36 Quality of Life (QoL) and a bowel diary. Initially, all patients underwent a temporary implant for 4 weeks. The criteria of success were disappearance of necessity for laxatives or enema requirement, and improvement in QoL.

RESULTS

Fifteen patients with STC were treated from March 2003 to May 2006. Nine (60%) underwent permanent implantation. After SNM, the mean improvement of Wexner Constipation Score (CCS) and QoL was 10 and 6.2 respectively. There were no complications. The mean follow-up period was 42 months.

CONCLUSION

Sacral nerve modulation seems to be a useful option for STC.

Sacral nerve stimulation for constipation: do we still miss something? Role of psychological evaluation

INTRODUCTION

The aim of this study was to try to understand if psychological evaluation of patients candidate to sacral nerve stimulation (SNS) could be a potential selection criterion to identify those patients who could successfully respond to this treatment.

MATERIALS AND METHODS

From 2005 to 2007, 68 patients with slow transit constipation were identified, and all of them fulfill the selection criteria for the SNS treatment. The MMPI-2 test was purposed to all the patients. Wexner score, bowel movements, and SF36 were recorded in all the patients.

RESULTS

Twenty-three patients (33.8%) refused the psychological evaluation. Forty-five patients completed the test: only 13 patients (19.1%) had a score in the normal range of the scales of the MMPI-2 and were implanted with the temporary test for SNS. After the screening period, 11 patients (84.6%) reported more than 50% improvement of bowel movements per week and no need of laxatives, so they were definitively implanted. The mean follow-up period was 22 months (range 12-36). The mean number of bowel movements per week and Wexner score were significantly improved after 1 year (p < 0.001).

CONCLUSIONS

A complete and accurate psychological evaluation could be very important in the selection of the patients with STC that could benefit from SNS.