Five-year single center experience of sacral neuromodulation for isolated fecal incontinence or fecal incontinence combined with low anterior resection syndrome

Clinical Management of Low Anterior Resection Syndrome: Review of the Current Diagnosis and Treatment

BACKGROUND

Low anterior resection syndrome (LARS) is a series of bowel dysfunction symptoms, including altered bowel frequency, irregular bowel rhythms, fecal incontinence, and constipation. LARS occurs in 80% of patients undergoing sphincter-preserving surgery, affecting patients' quality of life along with social avoidance. Different measurements and treatments have been raised to deal with LARS, but no systematic standard has been developed.

OBJECTIVE AND METHODS

To promote the standardization of clinical trials and clinical management of LARS, this review summarizes the latest findings up until 2023 regarding the diagnostic criteria, assessment protocols, and treatment modalities for postoperative LARS in rectal cancer.

RESULTS

The diagnostic criteria for LARS need to be updated to the definition proposed by the LARS International Collaborative Group, replacing the current application of the LARS score. In both clinical trials and clinical treatment, the severity of LARS should be assessed using at least one symptom assessment questionnaire, the LARS score or MSKCC BFI, and at least one scale related to quality of life. Anorectal manometry, fecoflowmetry, endoscopic ultrasonography, and pelvic floor muscle strength testing are recommended to be adopted only in clinical trials. After analysis of the latest literature on LARS treatment, a stepwise classification model is established for the standardized clinical management of LARS. Patients with minor LARS can start with first-line treatment, including management of self-behavior with an emphasis on diet modification and medication. Lamosetron, colesevelam hydrochloride, and loperamide are common antidiarrheal agents. Second-line management indicates multi-mode pelvic floor rehabilitation and transanal irrigation. Patients with major LARS should select single or several treatments in second-line management. Refractory LARS can choose antegrade enema, neuromodulation, or colostomy.

CONCLUSIONS

In clinical trials of LARS treatment between 2020 and 2022, the eligibility criteria and evaluation system have been variable. Therefore, it is urgent to create a standard for the diagnosis, assessment, and treatment of LARS. Failure to set placebos and differentiate subgroups are limitations of many current LARS studies. Randomized controlled trials comparing diverse therapies and long-term outcomes are absent, as well. Moreover, a new scale needs to be developed to incorporate the patient's perspective and facilitate outpatient follow-up. Though the establishment of a stepwise classification model for LARS treatment here is indispensable, the refinement of the guidelines may be improved by more standardized studies.

Sacral neuromodulation for low anterior resection syndrome: current status-a systematic review and meta-analysis

INTRODUCTION

It is estimated that approximately 70% of patients with rectal cancer who undergo surgery will suffer from Low Anterior Resection Syndrome (LARS). In the last decades, sacral neuromodulation (SNM) has been widely used in urinary dysfunction and in faecal incontinence refractory to medical treatment. Its application in LARS has been investigated and has shown promising results. The paper's aim is to present a systematic review and meta-analysis of the available literature and evaluate the therapeutic success of SNM in patients with LARS.

METHODS

A systematic search was performed in international health-related databases: Cochrane Library, EMBASE, PubMed and SciELO. No restrictions on year of publication or language were applied. Retrieved articles were screened and selected according to set inclusion criteria. Data items were collected and processed for each included article and a meta-analysis was done according to the PRISMA guidelines. The primary outcome was the number of successful definitive SNM implants. Further outcomes included changes in bowel habits, incontinence scores, quality of life scores, anorectal manometry data and complications.

RESULTS

A total of 18 studies were included, with 164 patients being submitted to percutaneous nerve evaluation (PNE) with 91% responding successfully. During follow-up of therapeutic SNM some devices were explanted. The final clinical success rate was 77% after permanent implant. Other outcomes, such as the frequency of incontinent episodes, faecal incontinence scores, quality of life scores were overall improved after SNM. The meta-analysis showed a decrease in 10.11 incontinent episodes/week; a decrease of 9.86 points in the Wexner score and an increase in quality of life of 1.56 (pooled estimate). Changes in anorectal manometry were inconsistent. Local infection was the most common post-operative complication, followed by pain, mechanical issues, loss of efficacy and haematoma.

DISCUSSION/CONCLUSION

This is the largest systematic review and meta-analysis concerning the use of SNM in LARS patients. The findings support the available evidence that sacral neuromodulation can be effective in the treatment of LARS, with significant improvement in total incontinent episodes and patients´ quality of life.

[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.

Machine learning model for prediction of low anterior resection syndrome following laparoscopic anterior resection of rectal cancer: A multicenter study

BACKGROUND

Low anterior resection syndrome (LARS) severely impairs patient postoperative quality of life, especially major LARS. However, there are few tools that can accurately predict major LARS in clinical practice.

AIM

To develop a machine learning model using preoperative and intraoperative factors for predicting major LARS following laparoscopic surgery of rectal cancer in Chinese populations.

METHODS

Clinical data and follow-up information of patients who received laparoscopic anterior resection for rectal cancer from two medical centers (one discovery cohort and one external validation cohort) were included in this retrospective study. For the discovery cohort, the machine learning prediction algorithms were developed and internally validated. In the external validation cohort, we evaluated the trained model using various performance metrics. Further, the clinical utility of the model was tested by decision curve analysis.

RESULTS

Overall, 1651 patients were included in the present study. Anastomotic height, neoadjuvant therapy, diverting stoma, body mass index, clinical stage, specimen length, tumor size, and age were the risk factors associated with major LARS. They were used to construct the machine learning model to predict major LARS. The trained random forest (RF) model performed with an area under the curve of 0.852 and a sensitivity of 0.795 (95%CI: 0.681-0.877), a specificity of 0.758 (95%CI: 0.671-0.828), and Brier score of 0.166 in the external validation set. Compared to the previous preoperative LARS score model, the current model exhibited superior predictive performance in predicting major LARS in our cohort (accuracy of 0.772 for the RF model vs 0.355 for the preoperative LARS score model).

CONCLUSION

We developed and validated a robust tool for predicting major LARS. This model could potentially be used in the clinic to identify patients with a high risk of developing major LARS and then improve the quality of life.

Pelvic floor muscle exercises alleviate symptoms and improve mental health and rectal function in patients with low anterior resection syndrome

Background

Pelvic floor rehabilitation has been reported to be effective in improving fecal incontinence. The aim of this study was to prospectively evaluate the effectiveness of combined pelvic floor muscle exercises (PFMEs) and loperamide treatment on rectal function and mental health for low anterior resection syndrome (LARS) patients after sphincter-saving operation (SSO) for rectal cancer.

Methods

A total of 60 inpatients diagnosed with LARS were enrolled and randomly assigned to one of two groups: patients in Group A (n = 30) were treated with a PFME intervention and those in Group B (n = 30) with a control intervention for 4 weeks. High-resolution anorectal manometry (HRAM) was performed for all LARS patients. Demographic information was collected for all patients, and they subsequently also completed several questionnaires, including the Hospital Anxiety and Depression Scale (HADS), a measure of Wexner score, a measure of stool frequency per day, and the Bristol Stool Form Scale (BSFS).

Results

No significant differences between the groups were observed in baseline data. With regard to rectal function, we found significant improvements at week 4 in maximal resting pressure (MRP) (39.93 ± 5.02 vs. 28.70 ± 5.40 mmH₂O, p < 0.001) and maximal squeeze pressure (MSP) (132.43 ± 8.16 mmH₂O vs. 113.33 ± 9.87 mmH₂O, p < 0.001) among Group A patients compared to Group B patients. Additionally, Wexner scores were significantly lower in Group A than in Group B at week 4 (8.10 ± 1.24 vs. 9.87 ± 1.29 ml, p = 0.018), as were stool frequency (6.47 ± 0.90 vs. 7.83 ± 0.93, p < 0.001) and BSFS scores (5.17 ± 0.65 vs. 6.10 ± 0.80, p = 0.020). Notably, HADS scores were also significantly lower in Group A than in Group B at week 4 (8.25 ± 2.36 vs. 10.48 ± 3.01, p < 0.001). Additionally, both anxiety scores (4.16 ± 1.38 vs. 5.33 ± 1.69, p < 0.001) and depression scores (4.09 ± 1.56 vs. 5.15 ± 1.89, p < 0.001) were significantly lower in Group A than in Group B at week 4.

Conclusion

Pelvic floor muscle exercises are an effective treatment that can alleviate symptoms and improve rectal function and mental health in patients with low anterior resection syndrome.

Long-term results of sacral neuromodulation for the treatment of anorectal diseases

INTRODUCTION

Sacral neuromodulation (SNM) aims to improve anorectal function in patients with disorders of anal continence and rectal emptying. The mechanism of action of SNM is not well known, and its indications are still under evaluation. We report the functional results and morbidity of a prospective cohort treated between 2002 and 2019.

RESULTS

A total of 284 patients (of 423 tested) had implantation of a SNM. Five patients (1.8%) were lost to follow-up. Among those who had implantation, the indications for SNM were anal incontinence (n=376), refractory constipation (n=17), anterior resection syndrome (n=13), solitary rectal ulcer syndrome (n=7), and chronic inflammatory bowel disease (IBD) (n=10). The morbidity rate was 2.7% (Dindo-Clavien>2), 33 patients (11%) required explantation for infection (n=5), pain (n=2), inefficacy (n=24) or other reasons (rectal cancer) (n=3). It was necessary to change the stimulator in 68 patients (24%) during the follow-up period. Regarding the group of patients with anal incontinence, functional results showed improvement of the incontinence score in 40% and of quality of life in 25% after a mean follow-up of 55months.

CONCLUSION

SNM constitutes a mini-invasive treatment associated with low morbidity. Its' efficacy in anal incontinence makes it a priority approach. Other indications are still under evaluation; while results are promising, they are highly variable.

Reprogramming Sacral Neuromodulation for Sub-Optimal Outcomes: Evidence and Recommendations for Clinical Practice

Objectives

In some patients treated for urinary or fecal incontinence with sacral neuromodulation (SNM) persistence of symptoms, a reduction in efficacy or adverse effects of stimulation can occur. In such situations, further programming of the SNM device can help resolve problems. Infrequently hardware failure is detected. This article aims to provide practical guidance to solve sub‐optimal outcomes (troubleshooting) occurring in the course of SNM therapy.

Materials and Methods

A systematic literature review was performed. Collective clinical experience from an expert multidisciplinary group was used to form opinion where evidence was lacking.

Results

Circumstances in which reprogramming is required are described. Actions to undertake include changes of electrode configuration, stimulation amplitude, pulse frequency, and pulse width. Guidance in case of loss of efficacy and adverse effects of stimulation, developed by a group of European experts, is presented. In addition, various hardware failure scenarios and their management are described.

Conclusions

Reprogramming aims to further improve patient symptoms or ensure a comfortable delivery of the therapy. Initial changes of electrode configuration and adjustment of stimulation parameters can be performed at home to avoid unnecessary hospital visits. A logical and stepwise approach to reprogramming can improve the outcome of therapy and restore patient satisfaction.

Sacral Neuromodulation in Patients With Neurogenic Lower Urinary Tract Dysfunction: A Multicenter Retrospective Study From China

OBJECTIVES

This retrospective study aimed to determine the effectiveness of sacral neuromodulation (SNM) on neurogenic lower urinary tract dysfunction (NLUTD) and analyze the predictive factors.

MATERIALS AND METHODS

From January 2012 to January 2020, 152 subjects with NLUTD from four medical centers in China received SNM test stimulation. Subjects were assessed via bladder diaries, postvoid residual volumes (PRVs) and neurogenic bowel dysfunction (NBD) scores before and during the testing period. Patients who showed a minimum 50% improvement in symptoms through the SNM test phase were eligible for permanent SNM implantation.

RESULTS

The pooled success rate for chronic urinary retention was 31.0% (40/129), which was significantly lower (p < 0.05) than the rates for frequency-urgency (64.8%, 59/91), urinary incontinence (65.2%, 30/46), and NBD score (61.7%, 82/133). The results of the risk factor analysis showed that the urinary storage symptom was a statistically significant positive predictor (p = 0.001).

CONCLUSIONS

In conclusion, SNM is an effective and reliable method for treating NLUTD, especially in patients with urinary storage symptoms. Although not all of the symptoms in every patient can be resolve, SNM still might be a superior choice together with other treatment procedures.

Optimising functional outcomes in rectal cancer surgery

Background

By improved surgical technique such as total mesorectal excision (TME), multimodal treatment and advances in imaging survival and an increased rate of sphincter preservation have been achieved in rectal cancer surgery. Minimal-invasive approaches such as laparoscopic, robotic and transanal-TME (ta-TME) enhance recovery after surgery. Nevertheless, disorders of bowel, anorectal and urogenital function are still common and need attention.

Purpose

This review aims at exploring the causes of dysfunction after anterior resection (AR) and the accordingly preventive strategies. Furthermore, the indication for low AR in the light of functional outcome is discussed. The last therapeutic strategies to deal with bowel, anorectal, and urogenital disorders are depicted.

Conclusion

Functional disorders after rectal cancer surgery are frequent and underestimated. More evidence is needed to define an indication for non-operative management or local excision as alternatives to AR. The decision for restorative resection should be made in consideration of the relevant risk factors for dysfunction. In the case of restoration, a side-to-end anastomosis should be the preferred anastomotic technique. Further high-evidence clinical studies are required to clarify the benefit of intraoperative neuromonitoring. While the function of ta-TME seems not to be superior to laparoscopy, case-control studies suggest the benefits of robotic TME mainly in terms of preservation of the urogenital function. Low AR syndrome is treated by stool regulation, pelvic floor therapy, and transanal irrigation. There is good evidence for sacral nerve modulation for incontinence after low AR.