Automatic muscle impedance and nerve analyzer (AMINA) as a novel approach for classifying bioimpedance signals in intraoperative pelvic neuromonitoring

Frequent complications arising from low anterior resections include urinary and fecal incontinence, as well as sexual disorders, which are commonly associated with damage to the pelvic autonomic nerves during surgery. To assist the surgeon in preserving pelvic autonomic nerves, a novel approach for intraoperative pelvic neuromonitoring was investigated that is based on impedance measurements of the innervated organs. The objective of this work was to develop an algorithm called AMINA to classify the bioimpedance signals, with the goal of facilitating signal interpretation for the surgeon. Thirty patients included in a clinical investigation underwent nerve-preserving robotic rectal surgery using intraoperative pelvic neuromonitoring. Contraction of the urinary bladder and/or rectum, triggered by direct stimulation of the innervating nerves, resulted in a change in tissue impedance signal, allowing the nerves to be identified and preserved. Impedance signal characteristics in the time domain and the time-frequency domain were calculated and classified to develop the AMINA. Stimulation-induced positive impedance changes were statistically significantly different from negative stimulation responses by the percent amplitude of impedance change Amax in the time domain. Positive impedance changes and artifacts were distinguished by classifying wavelet scales resulting from peak detection in the continuous wavelet transform scalogram, which allowed implementation of a decision tree underlying the AMINA. The sensitivity of the software-based signal evaluation by the AMINA was 96.3%, whereas its specificity was 91.2%. This approach streamlines and automates the interpretation of impedance signals during intraoperative pelvic neuromonitoring.

Technical aspects of a new approach to intraoperative pelvic neuromonitoring during robotic rectal surgery

It has been found that rectal surgery still leads to high rates of postoperative urinary, fecal, or sexual dysfunction, which is why nerve-sparing surgery has gained increasing importance. To improve functional outcomes, techniques to preserve pelvic autonomic nerves by identifying anatomic landmarks and implementing intraoperative neuromonitoring methods have been investigated. The objective of this study was to transfer a new approach to intraoperative pelvic neuromonitoring based on bioimpedance measurement to a clinical setting. Thirty patients (16 male, 14 female) involved in a prospective clinical investigation (German Clinical Trials Register DRKS00017437, date of first registration 31/03/2020) underwent nerve-sparing rectal surgery using a new approach to intraoperative pelvic neuromonitoring based on direct nerve stimulation and impedance measurement on target organs. Clinical feasibility of the method was outlined in 93.3% of the cases. Smooth muscle contraction of the urinary bladder and/ or the rectum in response to direct stimulation of innervating functional nerves correlated with a change in tissue impedance compared with the pre-contraction state. The mean amplitude (Amax) of positive signal responses was Amax = 3.8%, negative signal responses from a control tissue portion with no stimulation-induced impedance change had an amplitude variation of 0.4% on average. The amplitudes of positive and negative signal responses differed significantly (statistical analysis using two-sided t-test), allowing the nerves to be identified and preserved. The results indicate a reliable identification of pelvic autonomic nerves during rectal surgery.

Resection rectopexy as part of the multidisciplinary approach in the management of complex pelvic floor disorders

Objectives

Pelvic floor disorders are frequently caused by an organ prolapse involving multiple pelvic floor compartments. In such cases, a multidisciplinary strategy for diagnostic work-up and therapy is required.

Methods

All patients who underwent transabdominal rectopexy/resection rectopexy alone or in combination with simultaneous gynecological pelvic floor reconstruction at our institution between 01/2006 and 12/2021 were included in this retrospective study. The study aimed to evaluate the functional outcome and postoperative complications.

Results

Two hundred and eighty seven patients were assigned to one of the following groups: PG1 - patient group one: after resection rectopexy (n=141); PG2 - after ventral rectopexy (n=8); PG3 - after combined resection rectopexy and sacro (cervico)colpopexy (n=62); PG4 - after combined resection rectopexy and trans-vaginal pelvic floor repair (n=76). The duration of follow-up was 14 months for PG1 (median, IQR 37 months), 11 months for PG2 (mean, SD 9 months), 7 months for PG 3 (median, IQR 33 months), and 12 months for PG 4 (median, IQR 51 Months). The surgical procedure resulted in improvement of symptoms related to obstructed defecation in 56.4 % (22/39) of the patients in PG1, 25 % in PG2 (1/4), 62.5 % (20/32) in PG3, and 71.8 % (28/39) in PG4. "De novo" constipation was reported by 2.4 % (2/141) of patients from PG1. Improvement in fecal incontinence symptoms was reported by 69 % (40/58) of patients in PG1, 100 % in PG2 (2/2), 93.1 % (27/29) in PG3, and 87.2 % (34/39) in PG4. The recurrence rate for external rectal prolapse was 7.1 % in PG1, 50 % in PG2 (1/2), 2.7 % in PG3, and 6.3 % in PG4. A significant difference in terms of severe morbidity (grade ≥ IIIb) and mortality could not be determined between the non-interdisciplinary (PG1 with PG2) and interdisciplinary surgery (PG3 with PG4) (p=0.88, p=0.499).

Conclusions

Based on our results, we can assume that combined surgery is as feasible as rectal surgery alone. In our study, combined interventions were effective and not associated with an increased risk of postoperative complications.

[Stoma-associated complications-Prevention strategy and treatment concepts]

Postoperative complications after the creation of an intestinal stoma have a considerable impact on the patient's quality of life. The accurate surgical technique is very important for their prevention and requires profound surgical knowledge as well as sufficient experience. The importance of the preoperative consultation as well as the postoperative care by stoma therapists is clearly proven. Depending on the severity of the complication, outpatient conservative treatment is initially indicated. A surgical local revision or laparotomy should only be considered if conservative treatment is no longer sufficient, whereby the indications for surgery should be set very cautiously. This article provides an overview of the current evidence regarding the prevention and treatment of postoperative stoma complications.

The Indications for and Timing of Surgery for Diverticular Disease

BACKGROUND

Diverticular disease is one of the more common abdominal disorders. In 2016, approximately 130 000 patients received inpatient treatment for diverticular disease in Germany. The disease has a number of subtypes, each of which has an appropriate treatment. In this article, we present the current surgical indications and optimal timing of surgery for diverticular disease.

METHODS

This review is based on publications that were retrieved by an extensive, selective search in Medline and the Cochrane Library (1998-2018) for studies and guidelines with information on the indications for surgery in diverticular disease.

RESULTS

Studies of evidence grades 2 to 4 were available. Patients receiving a diagnosis of freely perforated diverticulitis and peritonitis (Classification of Diverticular Disease [CDD] type 2c) should be operated on at once. Covered perforated diverticulitis with a macroabscess (>1 cm, CDD type 2b) may be an indication for elective surgery after successful conservative treatment. New evidence from a randomized, controlled trial suggests that elective surgery should also be considered for patients with chronic recurrent diverticulitis (CDD type 3b). The decisive factor in such cases is the impairment of the quality of life for the individual patient. Elective surgery is indicated in chronic recurrent diverticulitis with complications (fistulae, stenoses). Asymptomatic diverticulosis (CDD type 0) and uncomplicated diverticulitis (CDD type 1) are not surgical indications. Likewise, in diverticular hemorrhage (CDD type 4), surgery is only indicated in exceptional cases, when conservative treatment fails.

CONCLUSION

The surgical indication and the proper timing of surgery depend on the type of disease that is present. Future studies should more thoroughly investigate the effect of surgery on the quality of life in patients with the various types of diverticular disease.

The modified Blumgart anastomosis after pancreaticoduodenectomy: a retrospective single center cohort study

Objectives

The postoperative pancreatic fistula (POPF) is a major complication after pancreatic head resection whereby the technique of the anastomosis is a very influencing factor. The literature describes a possible protective role of the Blumgart anastomosis.

Methods

Patients after pancreatic head resection with reconstruction through the modified Blumgart anastomosis (a 2 row pancreatic anastomosis through mattress sutures of the parenchyma and duct to mucosa pancreaticojejunostomy, Blumgart-group) were compared with patients after pancreatic head resection and reconstruction through the conventional pancreatojejunostomy (single suture technique of capsule and parenchyma to seromuscularis, PJ-group). The Data were collected retrospectively. Depending on the propensity score matching in a ratio of 1:2 comparison groups were set up. Blumgart-group (n=29) and PJ-group (n=56). The primary end point was the rate of POPF. Secondary goals were duration of operation, length of hospital stay, length of stay on intermediate care units and hospital mortality.

Results

The rate of POPF (biochemical leak, POPF "grade B" and POPF "grade C") was less in the Blumgart-group, but without statistical relevance (p=0.23). Significantly less was the rate of POPF "grade C" in the Blumgart-group (p=0.03). Regarding the duration of hospital stay, length of stay on intermediate care units and hospital mortality, there was no relevant statistical difference between the groups (p=0.1; p=0.4; p=0.7). The duration of the operation was significantly less in the Blumgart-group (p=0.001).

Conclusions

The modified Blumgart anastomosis technique may have the potential to decrease major postoperative pancreatic fistula.

Intraoperative fluorescence angiography with indocyanine green: retrospective evaluation and detailed analysis of our single-center 5-year experience focused on colorectal surgery

Objectives

Assessing bowel perfusion with indocyanine green fluorescence angiography (ICG-FA) shows positive effects on anastomotic healing in colorectal surgery.

Methods

A retrospective evaluation of 296 colorectal resections where we performed ICG-FA was undertaken from January 2014 until December 2018. Perfusion of the bowel ends measured with ICG-FA was compared to the visual assessment before and after performing the anastomosis. According to the observations, the operative strategy was confirmed or changed. Sixty-seven low anterior rectal resections (LARs) and 76 right hemicolectomies were evaluated statistically, as ICG-FA was logistically not available for every patient in our service and thus a control group for comparison resulted.

Results

The operative strategy based on the ICG-FA results was changed in 48 patients (16.2%), from which only one developed an anastomotic leakage (AL) (2.1%). The overall AL rate was calculated as 5.4%. Within the 67 patients with LAR, the strategy was changed in 11 patients (16.4%). No leakage was seen in those. In total three AL happened (4.5%), which was three times lower than the AL rate of 13.6% in the control group but statistically not significant. From the 76 right hemicolectomies a strategy change was undertaken in 10 patients (13.2%), from which only one developed an AL. This was the only AL reported in the whole group (1.3%), which was six times lower than the leakage rate of the control group (8.1%). This difference was statistically significant (p=0.032).

Conclusions

Based on the positive impact by ICG-FA on the AL rate, we established the ICG-FA into our clinical routine. Although randomized studies are still missing, ICG-FA can raise patient safety, with only about 10 min longer operating time and almost no additional risk for the patients.

[Influence of Local Insufflation of Warm Humidified CO2 on the Wound Surface and Body Core Temperature as well as on Wound Healing in Open Colorectal Surgery]

BACKGROUND

Perioperative hypothermia may lead to serious complications. This study aims to investigate whether intraoperative insufflation of warmed and humidified carbon dioxide (W-H-CO₂) into the open wound during open colorectal surgery influences body core and wound surface temperatures or the incidence of wound healing disorders (WHD).

METHODS

Between 02/2018 and 07/2019, 50 patients intended to undergo open resection for colorectal cancer were recruited and randomised to a control group (n = 25) and an experimental group (n = 25). In the experimental group, a device for insufflation of W-H-CO₂ was used. Body core and wound surface temperatures were recorded at the beginning and before finishing the procedure. IL-6 serum levels were determined preoperatively and during the postoperative course. Clinical observation of wound healing was performed until the 30th day post-op.

RESULTS

Both groups were homogeneous in terms of risk factors for WHD. In the control group, the median body core temperature (1. quartile/3. quartile) was 36.2 °C (36/36.4 °C) when the operation started and 36.2 °C (35.9/36.45 °C) at the end, while in the experimental group it was initially 36.2 °C (35.7/36.4 °C) and 36.4 °C (36/36.7 °C) at the end. There was no significant difference between the two groups (p = 0.08). The wound temperature in the control group dropped from 32.8 °C (median; 31.85/34.05 °C) to 30.7 °C (median; 29.85/32.15 °C). In the experimental group, we recorded a drop from 31.9 °C (median; 30.25/32.95 °C) to 31.6 °C (median; 30.25/31.85 °C), which was statistically significant (p = 0.000475). The dynamic of the IL-6 serum levels in both groups suggest that there was no significant difference (p = 0.66; p = 0.88; p = 0.88). In the control group, 8 patients experienced superficial WHD, 2 anastomotic leakages (AL), while in the experimental group, superficial WHD were observed in 5 patients and AL in 1 patient. This differences between the groups regarding in WHD were not significant (p = 0.42).

CONCLUSION

The established measures for prevention of perioperative hypothermia in elective procedures are sufficient. However, the local wound surface temperature is not preserved satisfactorily. Deployment of a device for intraoperative insufflation of W-H-CO₂ into open wounds may be suitable for maintaining local normothermia. Further studies are needed to determine the influence of warm and humid CO₂ on wound healing.

[Transanal total mesorectal excision-a critical appraisal]

INTRODUCTION

Total mesorectal excision (TME) is the international standard for rectal cancer surgery. In addition to laparoscopic TME (lapTME), transanal TME (taTME) was developed in recent years to reduce the rate of incomplete TME, conversion to open surgery and postoperative functional impairment. Despite limited evidence, this technique is becoming increasingly more popular and is already routinely used by many hospitals for rectal cancer in varying tumor level locations. The aim of this review was to evaluate the taTME compared to anterior rectal resection with lapTME as the standard of care in rectal cancer surgery based on currently available evidence.

METHOD

The databases PubMed and Medline were systematically searched for publications on transanal total mesorectal excision (taTME) and transanal minimally invasive surgery (TAMIS). Relevant studies were selected and further research based on the reference lists was undertaken.

RESULTS

A total of 16 studies analyzing 3782 patients were identified. The taTME does not lead to a higher rate of complete TME-resected specimens compared to the standard procedure. So far, superiority could not be demonstrated for complication rates or for functional or oncological results. Serious complications secondary to dissection in incorrect planes were observed. The anastomotic level generally seems to be closer to the sphincter after taTME versus anterior lapTME.

CONCLUSION

Considering current evidence, taTME failed to show superiority compared to conventional anterior lapTME. Although taTME has some potential advantages, it carries substantial risks. If performed outside of clinical trials, it should therefore only be used in carefully selected patients with a high possibility of conversion, following adequate patient informed consent and after intense and systematic training of the surgeon.

German S3 guidelines: anal abscess and fistula (second revised version)

BACKGROUND

The incidence of anal abscess and fistula is relatively high, and the condition is most common in young men.

METHODS

This is a revised version of the German S3 guidelines first published in 2011. It is based on a systematic review of pertinent literature.

RESULTS

Cryptoglandular abscesses and fistulas usually originate in the proctodeal glands of the intersphincteric space. Classification depends on their relation to the anal sphincter. Patient history and clinical examination are diagnostically sufficient in order to establish the indication for surgery. Further examinations (endosonography, MRI) should be considered in complex abscesses or fistulas. The goal of surgery for an abscess is thorough drainage of the focus of infection while preserving the sphincter muscles. The risk of abscess recurrence or secondary fistula formation is low overall. However, they may result from insufficient drainage. Primary fistulotomy should only be performed in case of superficial fistulas. Moreover, it should be done by experienced surgeons. In case of unclear findings or high fistulas, repair should take place in a second procedure. Anal fistulas can be treated only by surgical intervention with one of the following operations: laying open, seton drainage, plastic surgical reconstruction with suturing of the sphincter (flap, sphincter repair, LIFT), and occlusion with biomaterials. Only superficial fistulas should be laid open. The risk of postoperative incontinence is directly related to the thickness of the sphincter muscle that is divided. All high anal fistulas should be treated with a sphincter-saving procedure. The various plastic surgical reconstructive procedures all yield roughly the same results. Occlusion with biomaterial results in lower cure rate.

CONCLUSION

In this revision of the German S3 guidelines, instructions for diagnosis and treatment of anal abscess and fistula are described based on a review of current literature.

German S3-Guideline: rectovaginal fistula

Background: Rectovaginal fistulas are rare, and the majority is of traumatic origin. The most common causes are obstetric trauma, local infection, and rectal surgery. This guideline does not cover rectovaginal fistulas that are caused by chronic inflammatory bowel disease.

Methods: A systematic review of the literature was undertaken.

Results: Rectovaginal fistula is diagnosed on the basis of the patient history and the clinical examination. Other pathologies should be ruled out by endoscopy, endosonography or tomography. The assessment of sphincter function is valuable for surgical planning (potential simultaneous sphincter reconstruction).

Persistent rectovaginal fistulas generally require surgical treatment. Various surgical procedures have been described. The most common procedure involves a transrectal approach with endorectal suture. The transperineal approach is primarily used in case of simultaneous sphincter reconstruction. In recurrent fistulas. Closure can be achieved by the interposition of autologous tissue (Martius flap, gracilis muscle) or biologically degradable materials. In higher fistulas, abdominal approaches are used as well.

Stoma creation is more frequently required in rectovaginal fistulas than in anal fistulas. The decision regarding stoma creation should be primarily based on the extent of the local defect and the resulting burden on the patient.

Conclusion: In this clinical S3-Guideline, instructions for diagnosis and treatment of rectovaginal fistulas are described for the first time in Germany. Given the low evidence level, this guideline is to be considered of descriptive character only. Recommendations for diagnostics and treatment are primarily based the clinical experience of the guideline group and cannot be fully supported by the literature.

Cryptoglandular anal fistulas

BACKGROUND

Cryptoglandular anal fistula arises in 2 per 10 000 persons per year and is most common in young men. Improper treatment can result in fecal incontinence and thus in impaired quality of life.

METHOD

This S3 guideline is based on a systematic review of the pertinent literature.

RESULTS

The level of evidence for treatment is low, because relevant randomized trials are scarce. Anal fistulae are classified according to the relation of the fistula channel to the sphincter. The indication for treatment is established by the clinical history and physical examination. During surgery, the fistula should be probed and/or dyed. Endo-anal ultrasonography and magnetic resonance imaging are of roughly the same diagnostic value and may be useful as additional studies for complex fistulae. Surgical treatment is with one of the following operations: laying open, seton drainage, plastic surgical reconstruction with suturing of the sphincter, and occlusion with biomaterials. Only superficial fistulae should be laid open. The risk of postoperative incontinence is directly related to the thickness of sphincter muscle that is divided. All high anal fistulae should be treated with a sphincter-saving procedure. The various plastic surgical reconstructive procedures all yield roughly the same results. Occlusion with biomaterials yields a lower cure rate.

CONCLUSION

This is the first German S3 guideline for the treatment of cryptoglandular anal fistula. It includes recommendations for the diagnostic evaluation and treatment of this clinical entity.

[Principles and quality control of surgical therapy of rectal carcinoma]

During the past years, it has been possible to achieve impressive success in the treatment of rectal carcinoma through standardized therapeutic concepts. Through the consistent application of total mesorectal excision (TME) as a therapeutic procedure, a dramatic improvement in local recurrence rate has been attained. Future strategies are now aimed at improving postoperative quality of life and moreover, at reducing the incidence of distant metastasization. The positive development during recent years is ultimately also the result of increasing quality control. Hence, surgery with its specific quality criteria has been integrated into a broad spectrum of various individual factors that must be taken into consideration in a multimodal therapeutic concept.

Empfehlungen zur Anorektalen Manometrie im Erwachsenenalter

This document contains the guidelines of the German Societies of Neurogastroenterology and Motility, Gastroenterology (committee for proctology), Abdominal Surgery (coloproctology working group), and Coloproctology for anorectal manometry in adults. Recommendations are given about technical notes, study preparation (equipment; patient), technique for performing manometry and data analysis, reproducibility, and indications. Minimum standards for anorectal manometry are measurement of resting and squeeze pressure, testing of rectoanal inhibitory reflex, determination of rectal sensation (first perception and urge), and calculation of rectal compliance. Anorectal manometry is indicated in patients with fecal incontinence and constipation in the context of a structured programme.

Increased serum levels of complement C3a anaphylatoxin indicate the presence of colorectal tumors

BACKGROUND & AIMS

Late diagnosis of colorectal carcinoma results in a significant reduction of average survival times. Yet despite screening programs, about 70% of tumors are detected at advanced stages (International Union Against Cancer stages III/IV). We explored whether detection of malignant disease would be possible through identification of tumor-specific protein biomarkers in serum samples.

METHODS

A discovery set of sera from patients with colorectal malignancy (n = 58) and healthy control individuals (n = 32) were screened for potential differences using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. Candidate proteins were identified and their expression levels were validated in independent sample sets using a specific immunoassay (enzyme-linked immunosorbent assay).

RESULTS

By using class comparison and custom-developed algorithms we identified several m/z values that were expressed differentially between the malignant samples and the healthy controls of the discovery set. Characterization of the most prominent m/z values revealed a member of the complement system, the stable form of C3a anaphylatoxin (ie, C3a-desArg). Based on a specific enzyme-linked immunosorbent assay, serum levels of complement C3a-desArg predicted the presence of colorectal malignancy in a blinded validation set (n = 59) with a sensitivity of 96.8% and a specificity of 96.2%. Increased serum levels were also detected in 86.1% of independently collected sera from patients with colorectal adenomas (n = 36), whereas only 5.6% were classified as normal.

CONCLUSIONS

Complement C3a-desArg is present at significantly higher levels in serum from patients with colorectal adenomas (P < .0001) and carcinomas (P < .0001) than in healthy individuals. This suggests that quantification of C3a-desArg levels could ameliorate existing screening tests for colorectal cancer.

[Functional results after transvaginal, transperineal and transrectal correction of a symptomatic rectocele]

INTRODUCTION

The aim of this study was to compare functional outcome after transvaginal, transperineal and transrectal repair of a symptomatic rectocele and to develop the ideal surgical approach.

PATIENTS AND METHOD

28 patients (27 female, 1 male) who had undergone rectocele repair from 1996 to 2003 were analysed. Mean age was 59 years (range 30-79 years), follow-up was 24 months (range 3 to 70 months) and mean appearance of symptoms was 4 years prior to the operation (6 months-32 years). Transvaginal repair was performed in 13 cases, transperineal repair in 8 cases and transrectal repair in 7 cases.

RESULTS

24 of 28 patients (85.7 %) are satisfied with the operation-result (transvaginal 12 of 13 patients [92.3 %], transperineal 7 of 8 patients [87.5 %] and transrectal 5 of 7 patients [71.4 %]). 25 patients (89.3 %) are free of complaints or describe an evident improvement of symptoms (transvaginal 12 of 13 patients [92.3 %], transperineal 7 of 8 patients [87.5 %] und transrectal 6 of 7 patients [85.7 %]). There is one postoperative dyspareunia.

DISCUSSION

Best treatment of a rectocele starts with patients selection. Considering pelvic floor as functional unity, concomitant urologic-gynaecologic lesions and proximal intraabdominal disturbances the appropriate surgical procedure is selected.

CONCLUSION

Surgical approach to correct a symptomatic rectocele depends on the concomitant lesion.

Do geographic and educational factors influence the quality of life in rectal cancer patients with a permanent colostomy?

PURPOSE

This study was designed to evaluate possible social and geographic factors that could have an impact on quality of life in patients after abdominoperineal excision of the rectum. Although the number of patients with rectal cancer who need to be treated with abdominoperineal excision of the rectum and construction of permanent colostomy has greatly decreased in the past, there is still controversy about the influence on quality of life caused by this procedure.

METHODS

In a prospective trial, patients operated on for low rectal cancer by abdominoperineal excision of the rectum were evaluated by a quality of life questionnaire, modified from The American Society of Colon and Rectal Surgeons questionnaire, to assess fecal incontinence. The results for the four domains of quality of life (lifestyle, coping behavior, embarrassment, depression), as well as for subjective general health, were evaluated with regard to age, gender, education, and geographic origin in univariate and multivariate analyses.

RESULTS

Thirteen institutions in 11 countries included data from 257 patients. Although the analysis of general health did not reveal any significant differences, the analysis of the four quality of life domains showed the significant influence of geographic origin. The presence of a permanent colostomy showed a consistently negative impact on patients in southern Europe as well as for patients of Arabic (Islamic) origin. On the other hand, age, gender, and educational status did not reveal a statistically significant influence.

CONCLUSIONS

This is the first study to show the influence of geographic origin on quality of life of patients with a permanent colostomy. Possible factors that may influence the outcome of patients after surgical treatment of rectal cancer, such as weather, religion, or culture, should be taken into account when quality of life evaluations are considered.

Frühergebnisse nach laparoskopischer Operation bei Morbus Crohn

INTRODUCTION

During the last years laparoscopic surgical procedures are used more frequently in benign bowel diseases like Crohn's disease. We are reporting early results of laparoscopic procedures in Crohn's disease at our hospital.

PATIENTS AND METHOD

From 1994 to 2003 54 patients (20 male and 34 female) underwent laparoscopic colonic and small bowel surgery in Crohn's disease. The mean age was 32 years (range: 16 to 55 years).

RESULTS

Complications occurred in 6 patients (11.1 %). 3 patients needed a laparotomy. One computed tomography puncture was performed due to a hematoma. The remaining patients are treated successfully non-operatively. No patient died during the perioperative period. The mean operating time was 152 minutes (range 35 to 360 minutes) and the mean postoperative stay in hospital was 10 days (range 6-35 days). 0.2 blood cell concentrates were needed per operation (range 0 to 6), on average. The patients needed no analgesics after the 5 (th) day (range 1 to 13 days), got liquid diet on the 2 (nd) (range 0 to 6 days) and solid diet on the 3 (rd) day after surgery (range 1 to 14 days).

DISCUSSION

Laparoscopic surgery in Crohńs disease is safe when performed by an experienced surgeon. The laparoscopic procedure results in a better cosmetic result, while the longer operating time is the mean disadvantage. There are low complication rates during the early postoperative period.

Laparoscopic surgery for rectal prolapse and outlet obstruction

PURPOSE

The aim of this study was to assess the outcome of both laparoscopic suture rectopexy and resection-rectopexy in the treatment of complete and incomplete rectal prolapse, outlet obstruction, or both.

METHODS

Data from surgery were collected prospectively. Semiannual follow-up was performed by assessment of recurrence, continence, and constipation using patients' history, physical examination, continence score, and anorectal manometry. Statistical analysis was performed by chi-squared test and Student's t-test (P < 0.05 was accepted as statistically significant).

RESULTS

Between September 1992 and February 1997, 72 patients (68 females) with a mean age of 62 (range, 23-88) years were treated laparoscopically. Indications for surgery were rectal prolapse in 21 patients, rectal prolapse combined with outlet obstruction in 36 patients, and outlet obstruction alone in 15 patients. Standard procedure was a laparoscopic suture rectopexy. A sigmoid resection was added in 40 patients. Mean duration of surgery was 227 (range, 125-360) minutes for rectopexy and 258 (range, 150-380) minutes for resection-rectopexy. Conversion was necessary in 1.4 percent (n = 1). Overall complication rate was 9.7 percent (n = 7) and mortality rate was 0 percent. Mean postoperative hospitalization was 15 (range, 6-47) days. All patients with a minimal follow-up of two years (n = 53) could be enrolled in a prospective follow-up study (mean follow-up, 30 months). No recurrence of rectal prolapse had to be recognized. Sixty-four percent of patients with incontinence before surgery were continent or had improved continence. In patients experiencing constipation preoperatively, constipation was improved or completely removed in 76 percent. No additional symptoms of constipation occurred after surgery.

CONCLUSION

Laparoscopic procedures in the treatment of pelvic floor disorders, e.g., rectal prolapse or outlet obstruction, lead to acceptable functional results. However, follow-up has to be extended and long-term results of recurrence, continence, and constipation have to be evaluated.

Organization of the enteric nervous system in the human colon demonstrated by wholemount immunohistochemistry with special reference to the submucous plexus

To demonstrate the normal topography and structure of the enteric nervous system (ENS) in the human colon, the colonic wall of patients (n = 10, mean age 66.3 years), who underwent abdominal surgery unrelated to intestinal motility disorders, was submitted to wholemount immunohistochemistry. The specimens were stretched out and separated into the tunica muscularis, the outer and inner portion of the tela submucosa and the tunica mucosa. Prior to the application of the neuronal marker Protein Gene Product (PGP) 9.5, the laminar preparations were pretreated with the maceration agent KOH. The plexus myentericus was composed of prominent ganglia and interconnecting nerve fiber strands (NFS) forming a polygonal network, which was denser in the descending than in the ascending colon. Nerve cells were observed within the ganglia as well as in primary, secondary and tertiary NFS. The latter ramified into the adjacent smooth muscle layers, which contained the aganglionated plexus muscularis longitudinalis and circularis. The submucous plexus comprised three nerve networks of different topography and architecture: the delicate plexus submucosus extremus consisted of parallel orientated NFS with isolated nerve cells and small ganglia and was located at the outermost border of the tela submucosa adjacent to the circular muscle layer. The plexus submucosus externus was closely associated with the plexus submucosus extremus and composed of larger ganglia and thicker NFS. The plexus submucosus internus was situated adjacent to the lamina muscularis mucosae and formed a network with denser meshes but smaller ganglia and NFS than the plexus submucosus externus. The NFS of the aganglionated plexus muscularis mucosae followed the course of the smooth muscle cells of the lamina muscularis mucosae. The honeycomb-like network of the plexus mucosus was located within the lamina propria mucosae and divided into a subglandular and a periglandular portion. Single and accumulated nerve cells were observed within the plexus mucosus as a regular feature. The findings confirm the complex structural organisation of the ENS encountered in larger mammals, in particular the subdivision of the submucous plexus into three different compartments. PGP 9.5-immunohistochemistry applied to wholemount preparations comprehensively visualized the architecture of the intramural nerve plexus in human colonic specimens. In addition to conventional cross-sections, this technique allows a subtle assessment and classification of structural alterations of the ENS in patients with colorectal motor disorders.

[Immunocytochemical and molecular proof of disseminated tumor cells in bone marrow, peritoneal lavage, blood and regional lymph nodes. A review of the literature and own results]

Immunocytochemical or molecular detection of disseminated tumor cells in different compartments (bone marrow, abdomen, venous blood, lymph nodes) is becoming more and more important in determining the complete extent of the tumor at the time of primary therapy. However, their prognostic relevance is not clear up to now. Whereas their appearance in bone marrow revealed a poor prognosis in some studies, contradictory results have been obtained from examinations of lymph nodes. Moreover peritoneal lavage and venous blood have seldom been examined with these methods. Because standardization of the immunocytochemical or molecular techniques does not exist, therapeutical conclusions can not be drawn from their detection at this time.

[Peritoneal lavage in standardized peritonitis models]

The peritoneal lavage in peritonitis can be studied in a standardized manner only in animal models, because peritonitis is too variable and dependent on too many patient related factors. In this article answers are given to questions on the influence of different lavage substances on survival, local and systemic concentrations of bacteria, endotoxin, and TNF as well as on mesothelial adherence of bacteria. These data refer to results from acute models of infection published in the literature. Furthermore, we show from our own chronic peritonitis model the influence of the peritoneal lavage on abscess formation and translocation. After inoculation of a Bacteroides fragilis suspension, a chronic abscess forming peritonitis was induced. At day 3/7/14 intraabdominal abscesses were found in 2/4/6 of 8/5/6 animals in an untreated, in 1/3/5 of 5/5/5 animals in a saline lavaged, and in 5/0/2 of 5/5/5 animals in a Taurolidin lavaged group, respectively. Both, the intraabdominal and the systemic bacterial dissemination were more effectively inhibited by the Taurolidin lavage than by the saline lavage.

[Megacolon in adults--the spectrum of underlying intestinal innervation disorders]

The association of megacolon in adults and Hirschsprung's disease was reevaluated by the morphological assessment of the enteric nervous system. Whole-mount preparations of the resected colonic segments and an immunohistochemical treatment with the pan-neuronal marker protein gene product 9.5 allowed an optimal visualization of the entire intramural nervous plexus layers. The findings included different forms of intestinal neuronal malformations (hypoganglionosis, neuronal intestinal dysplasia, and heterotopic ganglia) apart from classic aganglionosis, thus indicating their etiologic relevance to the development of megacolon in adults.

[Laparoscopically assisted surgery in Crohn disease]

From Jan. 1993 to Apr. 1997 intestinal resections in Crohn's disease have been performed in 275 patients. 89 patients have been operated on laparoscopic assisted. The following parameters were analyzed: previous laparotomies, extent of resection, steroid medication, conversionrate, complications, operative time and postoperative stay. Endpoints were: conversionrate, complications, reconvalescence and overall satisfaction with the laparoscopic technique.

RESULTS

The duration of the disease ranged from 1 to 16 years (x = 6). 47 patients were under steroid medication at the time of surgery. 30 patients had undergone previous laparotomies. In 10 patients the operation had to be converted into open surgery. The following procedures have been performed: ileocaecal resections (45), anastomotic resections (14), small bowel resections (4), hemicolectomies (12), colectomies (9), loopileostomies (4), adhesiolysis (1). Minor complications occurred in 6.7% of patients, major complications in 5.6%. Operative time ranged from 70 to 420 minutes (x = 173.7). The postoperative hospital stay was 13.3 days in the average.

CONCLUSION

The morbidity of 12.3% is not higher than in open surgery. When complications do not occur the patients benefit from early convalescence, better cosmetics and shorter hospital stay.

[Current status of laparoscopic colorectal surgery--a nationwide survey]

Fifteen percent of all departments of surgery in Germany have experience with laparoscopic colorectal operations. Of the overall number of 143,000 cases, only about 1% were performed minimally invasively.

Assessment of the proliferation index in gastric carcinomas with the monoclonal antibody MIB 1

Our study aimed to reveal whether the proliferation index of tumor cells, calculated with the monoclonal antibody (mAb) MIB1, is of prognostic relevance in patients with a gastric carcinoma and shows any correlation to well-known clinicopathological factors (TNM categories, stage, grade, Laurén type). We examined formalin-fixed, paraffin-embedded tissue blocks of samples from 94 patients, who underwent surgery for an adenocarcinoma of the stomach between 1988 and 1991. Specimens were immunohistochemically stained using the mAb MIB1 in combination with the alkaline-phosphatase/anti-(alkaline phosphatase) technique. The proliferation index (PI) was estimated in various areas of interest (tumor center and periphery and in lymph node metastases of compartments I and II), by always counting 200 tumor cells in three different high-power fields per specimen, and calculated as the percentage of MIB1-positive tumor cell nuclei relative to all tumor cell nuclei in the area examined. The total PI in the primary tumor was 47.2% and slightly higher in the center (49.1%) compared to the periphery (44.7%). Surprisingly in lymph node metastases the PI was lower than in the primary tumor (compartment I: 39.5%, compartment II: 33.6%). Tumors with distant metastases revealed a higher proliferative activity (55.1%) than tumors without (44.3%). The PI increased significantly from well to poorly differentiated carcinomas (P < 0.01), whereas the intestinal Laurén type showed a lower PI than the diffuse type. No difference in survival was found between patients with a median PI or less and those with a PI above the median (47.2%). Our results show that the proliferation index in gastric carcinomas has no prognostic relevance and therefore is of low clinical value.

[Abdominal pain of uncertain origin--value of laparoscopy. "If in doubt, carry it out"]

Surgeons treating a patient with lower abdominal pain of uncertain etiology are caught between the extremes of conservative and operative treatment. After clinical examination and ultrasonography, explorative laparoscopy has been shown by several studies to solve this therapeutic dilemma. Using laparoscopy prolonged observation, the incidence of perforation and unnecessary laparotomies can be reduced dramatically, in particular, the rate of negative appendectomies is lowered from 30-40% to about 15%. This leads to shortened stay in hospital, increased efficiency and decreased financial costs.

[Intraluminal expansion of a small intestine segment--animal experiment principles and possible clinical application]

In this study we expanded ileal segments of 8 pigs with an intraluminal expander over a period of 6 to 8 weeks till the volume had reached approximately sixfold of the starting volume. The morphological and morphometrical examinations showed flattened villi with elongated crypts and especially an increase in the thickness of the muscularis. The villi appeared flattened through scanning microscopy as well, but the structure of the microvilli was nearly normal. The proliferative activity in the muscularis, estimated immunohistochemically by a monoclonal antibody against PCNA, showed a threefold increase. So it can be assumed, that the increased thickness of the muscle layer was caused not only by muscle cell hypertrophy but also by hyperplasia. The activity of the alpha-glucosidase, a brush border enzyme, was clearly reduced. The minor cause of this effect was the direct damage of the microvilli from the expander, but the major cause was the exclusion of the ileal segment from the small bowel passage and the resulting lack of nutrients. With our technique it seems possible to create an ileum pouch, a stomach substitute or a urinary bladder substitute.

[Malignant tumors of the small intestine. Diagnostic problems and differentiated surgical therapy]

The data of 27 patients who suffered from malignant tumors of the small bowel between 1970 and 1992 were retrospectively documented and evaluated. In the mainly elderly patients (5th to 8th decade of life) the tumor was most frequently localized in the ileum (41%), followed by the jejunum (30%) and the duodenum (22%). Adenocarcinoma was the most frequent histological diagnosis. Only 28% of the tumors were limited to the intestinal wall. 40% had metastases, local or to other organs. Due to diagnostic problems only 30% of these tumors were found preoperatively. In 22% of the cases an explorative laparotomy and in 33% an emergency operation because of ileus and/or peritonitis led to the correct diagnosis. Still, in 64% of the patients a R0-resection was possible. Nevertheless, the median period of survival was only 24.8 months. But patients who were R0-resected survived 65 months.