0000000001303054

AUTHOR

Werner Kneist

Lebermetastasen kolorektaler Karzinome - wie oft kann man operieren?

Recurrent liver metastases of colorectal carcinoma are frequent. The repeat hepatectomy is superior to other therapeutic options. In about 20 % of patients with recurrent liver metastases a complete resection (R 0) is possible. The morbidity of repeat hepatectomy is similar to that of first hepatectomy. The 5-year survival rate after repeat hepatectomy ranges between 30 and 40 %. Often in the follow-up additional operations become necessary for extrahepatic recurrencies. For determination of the optimal therapy an interdisciplinary approach must be chosen.

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Intraoperative neural electrode for continuous monitoring of nerve function

Nerve damage is still a major concern in all types of surgery and may result in permanent nerve injury. Real time nerve monitoring can reduce the risk of nerve lesions by continuous surveillance of nerve integrity. A stable proximal stimulation of the nerve and recording at the effector organ is essential and the electrodes should not significantly influence the surgical intervention.

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Modeling the pelvic region for non-invasive pelvic intraoperative neuromonitoring

Abstract Finite element analysis (FEA) of electric current distribution in the pelvis minor may help to assess the usability of non-invasive surface stimulation for continuous pelvic intraoperative neuromonitoring. FEA requires generation of quality volumetric tetrahedral mesh geometry. This study proposes the generation of a suitable mesh based on MRI data. The resulting volumetric mesh models the autonomous nerve structures at risk during total mesorectal excision. The model also contains the bone, cartilage, fat, skin, muscle tissues of the pelvic region, and a set of electrodes for surface stimulation. The model is ready for finite element analysis of the discrete Maxwell’s equations.

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Risk Factors for Urinary Dysfunction after Rectal Cancer Surgery

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Laparoscopic neuromapping in pelvic surgery: scopes of application.

Background. New developments in intraoperative electrophysiological neuromonitoring for conventional surgery are providing further insights into functional neuroanatomy and nerve-sparing in the minor pelvis. The aim of this study was to open up potential scopes of application in laparoscopy. Methods. Ten patients with different indications for surgery (presacral tumor excision, n = 2; resection rectopexy. n = 2; low anterior rectal resection, n = 2; proctocolectomy. n = 2; abdomino-perineal excision of the rectum, n = 2) were investigated prospectively. The pelvic autonomic nerves were bilaterally mapped by laparoscopic electric stimulation under simultaneous electromyography of the intern…

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Subtotal esophageal resection in motility disorders of the esophagus.

<i>Background:</i> Esophagectomy for motility disorders is performed infrequently. It is indicated after failed medical therapy, pneumatic dilation, non-resecting surgical and redo procedures. Patient selection in this group is challenging and the operative risk has to be weighted carefully against the poor quality of life with persistent or recurrent dysphagia. <i>Patients and Methods:</i> Between September 1985 and April 2004, subtotal esophageal resections for advanced esophageal motility disorders of the esophagus not responding to previous therapy were carried out in 8 patients (6 females, 2 males). The median age of these patients was 59.5 (43–78) years. Six pa…

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Adenokarzinom des Oesophagus: Prognosevergleich zwischen transthorakaler Oesophagusresektion mit erweiterter 2 Feld Lymphknotendissektion und transhiataler Oesophagusdissektion mit abdomineller Lymphknotendissektion

Ziel dieser Analyse war der Vergleich der beiden Operationsverfahren transthorakale oder transhiatale Resektion beim Adenokarzinom des Oesophagus. Von 1985 bis 2002 wurden 123 Patienten mit Adenokarzinom des Oesophagus reseziert, in 80 Fallen (65%) durch eine transhiatale Resektion mit abdomineller Lymphknotendissektion, in 43 Fallen (35%) durch transthorakale Resektion mit abdomineller- und mediastinaler Lymphknotendissektion.

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Transsacral rectocele following combined neurinoma resection: A case report

Highlights • Case of a combined (transsacral and laparoscopic) resection of a presacral tumour. • First described case of a transsacral rectocele two years after this procedure. • Possibility of laparoscopic defect repair of transsacral defects.

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Chirurgische Ausbildung im digitalen Zeitalter – Virtual Reality, Augmented Reality und Robotik im Medizinstudium

The digital transformation of healthcare is changing the medical profession. Augmented/Virtual Reality (AR/VR) and robotics are being increasingly used in different clinical contexts and require supporting education and training, which must begin within the medical school. There is currently a large discrepancy between the high demand and the number of scientifically proven concepts. The aim of this thesis was the conceptual design and structured evaluation of a newly developed learning/teaching concept for the digital transformation of medicine, with a special focus on the influence of surgical teaching.Thirty-five students participated in three courses of the blended learning curriculum "…

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Impact of inhalation vs. intravenous anaesthesia on autonomic nerves and internal anal sphincter tone.

Background Pelvic intraoperative neuromonitoring (pIONM) aims to identify and spare the autonomic nerves and maintain patients’ quality of life. The effect of anaesthetic agents on the pIONM signal is unknown; therefore, the aim of the present study was to compare the influences of inhalation anaesthesia (IA) and total intravenous anaesthesia (TIVA). Methods Twenty rectal cancer patients undergoing open nerve-sparing total mesorectal excision (TME) were assigned to pIONM under either IA or TIVA (n = 10 per group). IA was maintained with sevoflurane and TIVA with propofol. During surgery, pelvic autonomic nerves were electrically stimulated under electromyography (EMG) of the internal anal s…

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Common variants in the HLA-DQ region confer susceptibility to idiopathic achalasia

Idiopathic achalasia is characterized by a failure of the lower esophageal sphincter to relax due to a loss of neurons in the myenteric plexus(1,2). This ultimately leads to massive dilatation and an irreversibly impaired megaesophagus. We performed a genetic association study in 1,068 achalasia cases and 4,242 controls and fine-mapped a strong MHC association signal by imputing classical HLA haplotypes and amino acid polymorphisms. An eight-residue insertion at position 227-234 in the cytoplasmic tail of HLA-DQ beta 1 (encoded by HLA-DQB1*05:03 and HLA-DQB1*06:01) confers the strongest risk for achalasia (P = 1.73 x 10(-19)). In addition, two amino acid substitutions in the. extracellular …

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Virtuelle 3-D-Laparoskopie-Simulation in der chirurgischen Aus- und Weiterbildung – Ergebnisse einer Pilotstudie

Hintergrund: Dem technischen Fortschritt folgend, werden im Operationssaal Module zur 3-dimensionalen Darstellung in der Laparoskopie eingesetzt. Erste Untersuchungen an Box-Trainern haben diskrepante Ergebnisse gezeigt. Fur die Virtual-Reality-Laparoskopie (VRL) fehlen Daten zur 3-dimensionalen Simulation. Material und Methoden: 5 Facharzte fur Chirurgie, 10 chirurgisch tatige Arzte in Weiterbildung und 29 Medizinstudenten fuhrten abstrakte und prozedurale Ubungen am VRL-Simulator im 2-D- und 3-D-Modus durch. Die Reihenfolge der Durchfuhrung (2-D/3-D) wurde randomisiert. Ergebnisse: Fur Arzte und Studenten zeigten sich keine signifikanten Leistungsunterschiede fur Ubungen im 2-D- und 3-D-D…

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Tumor-, patienten- und operateurbezogene Einflussfaktoren der Identifikation und Schonung autonomer Beckennerven bei TME

Nachdem die onkologischen Ergebnisse durch Einfuhrung der Totalen Mesorektum Exzision (TME) zur Behandlung des Rektumkarzinoms verbessert wurden, war es Ziel einer prospektiven Untersuchung zu klaren wie haufig die Darstellung und Schonung autonomer Beckennerven moglich ist und ob ein Zusammenhang zu postoperativ auftretenden Blasenentleerungsstorungen besteht.

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Obere gastrointestinale Blutung mit hämorrhagischem Schock am Ende einer Urlaubsreise: Präklinische und innerklinische Versorgung eines gastrointestinalen Notfalls

ZusammenfassungNach der Rückkehr aus dem Urlaub wurde ein 55-jähriger Patient mit Teerstuhl und hämorrhagischem Schock im Zugabteil eines InterCity der Deutschen Bahn notfallmedizinisch versorgt und in ein Krankenhaus der Maximalversorgung eingeliefert. Hier erfolgte zunächst die weitere notfallmedizinische Behandlung, in deren Rahmen in der internistischen Notaufnahme in interdisziplinärer Zusammenarbeit eine Stabilisierung der Hämodynamik sowie die Sicherung der Atemwege und Atemfunktion erfolgten. Anschließend wurde eine Notfall-Endoskopie des oberen Gastrointestinaltrakts durchgeführt. Ursächlich für das hämorrhagische Schockgeschehen war eine arteriell spritzende, endoskopisch nicht zu…

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Design and fabrication of an ultra-flexible electrode system for invasive continuous monitoring during surgery

This paper introduces the development, design and characterization of a tube with electrodes for stimulation and recording. This tube can be used as an operative monitoring system for thyroid surgery. In such surgeries damaging of the neural tissue can result in permanently malfunction. Continuous nerve monitoring can reduce significantly this risk.

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Prospective Evaluation of Positron Emission Tomography in the Preoperative Staging of Esophageal Carcinoma

Hypothesis Positron emission tomography (PET) is a useful tool in the selection of patients with esophageal cancer who may not benefit from esophageal resection. Design Case series. Setting Tertiary care hospital. Patients Eighty-one patients with newly diagnosed esophageal cancer who underwent PET and computer tomography (CT) of the chest and abdomen (and of the neck in 45 patients) within 45 days were included. Main Outcome Measures We calculated the sensitivity and specificity in detecting metastatic sites on the basis of 31 histologically verified lesions. In addition to results obtained on CT, the information provided by PET was evaluated with a view to the choice of management strateg…

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Transanale totale mesorektale Exzision – Voraussetzungen zur sicheren Implementierung

ZusammenfassungDie transanale totale mesorektale Exzision (TaTME) ist eine innovative und technisch anspruchsvolle Methode zur chirurgischen Behandlung des Rektumkarzinoms. Ziel dieses Artikels ist es, die Voraussetzungen und Trainingsbedingungen darzustellen, die für die sichere Implementierung dieses komplexen Verfahrens entscheidend sind. Die internationalen Expertenmeinungen werden vor dem Hintergrund der veröffentlichten Ergebnisse aus TaTME-Schulungszentren diskutiert. Darüber hinaus werden eigene Erfahrungen aus den TaTME-Anatomiekursen (Video) und einer ersten klinischen Serie von 102 TaTMEs mitgeteilt. Das Verfahren sollte in erster Linie von kolorektal spezialisierten Fachärzten f…

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Selective pelvic autonomic nerve stimulation with simultaneous intraoperative monitoring of internal anal sphincter and bladder innervation.

<i>Background:</i> Pelvic autonomic nerve preservation avoids postoperative functional disturbances. The aim of this feasibility study was to develop a neuromonitoring system with simultaneous intraoperative verification of internal anal sphincter (IAS) activity and intravesical pressure. <i>Methods:</i> 14 pigs underwent low anterior rectal resection. During intermittent bipolar electric stimulation of the inferior hypogastric plexus (IHP) and the pelvic splanchnic nerves (PSN), electromyographic signals of the IAS and manometry of the urinary bladder were observed simultaneously. <i>Results:</i> Stimulation of IHP and PSN as well as simultaneous intraop…

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Laparoscopic gastric banding as a universal method for the treatment of patients with morbid obesity.

Introduction: This study analyzed the influence of potentially negative predictors such as sweet-eating behavior, super-obesity, social and psychological status, family and education situation, intake of sedative drugs, and the distance between hospital and home on the outcome of laparoscopic adjustable gastric banding (LAGB). Methods: 77 women and 29 men with mean age 40.6 years (28-47) underwent LAGB. Preoperative mean body weight was 146 kg (99-179), and mean BMI was 48.1 kg/m 2 (36.4-73.5). The influence of the above-mentioned potentially negative predictors on weight loss was the primary end point. Results: Mean follow-up was 44.6 ′ 19.7 months. Follow-up was possible in all but 6 pati…

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Iatrogene Ösophagusperforation bei transösophagealer Echokardiographie

History A 65-year-old patient underwent transesophageal echocardiography which caused a perforation of the upper esophagus. Three months after esophagostomy and gastrostomy the reconstruction was accomplished by a colon interposition graft. The patient postoperatively developed an ischemic necrosis of the graft, followed by a cervical fistula. Food intake and swallowing became impossible. Diagnosis X-ray examinations revealed the cervical fistula and a stenotic colon graft. Treatment and course The retrosternal colon graft was replaced by a gastric interposition graft, which was anastomosed with the cervical esophagus. The postoperative follow-up was normal at first. Increasing retention of…

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Influence of splenectomy on perioperative morbidity and long-term survival after esophagectomy in patients with esophageal carcinoma

The aim of this study was to determine the influence of splenectomy on perioperative morbidity and mortality, as well as on the long-term survival after esophageal resection for carcinoma of the esophagus. From September 1985 to July 2003, 404 patients underwent surgery for esophageal carcinoma in our institution. Splenectomy was performed in 34 (8.4%) patients. Perioperative morbidity and long-term survival were compared in patients with and without concomitant splenectomy. Splenectomy was associated with an increase in intraoperative blood loss and the need for transfusions of blood preserves (P0.0001). However, there were no significant differences in pulmonary, general, or surgical comp…

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Long-term urinary dysfunction after mesorectal excision: a prospective study with intraoperative electrophysiological confirmation of nerve preservation.

Bladder dysfunctions are well-recognized complications after nerve-sparing mesorectal excision for rectal cancer. This study sought to symptomatically analyze the extent of recovery from major and minor urinary symptoms in patients with signs of bladder denervation.Sixty-two patients with mesorectal excision for rectal cancer were investigated prospectively. Pelvic autonomic nerve preservation (PANP) was assessed macroscopically and with the aid of intraoperative electrical stimulation of pelvic autonomic nerves (INS). Bladder function was evaluated with the International Prostate Symptom Score (IPSS) and the Quality of life index (Qol). Median follow-up was 20 months (range 3-40 months).Fo…

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16 Jahre Myotomie und Semifundoplikatio nach Dor bei Achalasie — Die Langzeitergebnisse

Die Behandlung der Achalasie besteht in der Beseitigung der Schluckbeschwerden durch die Schwachung des unteren osophagussphinkter bei gleichzeitiger Vermeidung einer Reflux-symptomatik. Wenige Studien zu Langzeitergebnissen operativer Behandlung liegen vor. Ziel der Studie war die Erfassung der Langzeitergebnisse nach abdomineller Myotomie und Semifundoplicatio nach Dor bei Achalasie fur ein seit 1985 prospektiv erfasstes Krankengut. Patienten und Methode: 71 Patienten, 22 Manner und 49 Frauen, im Alter von 16 bis 78 Jahren wurden seit 1985 durch den selben Operateur behandelt. Die Anamnesedauer lag bei 3,5 Jahren im Median. Bereits behandelt durch Dilatation waren 66% und durch Operation …

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A Roadmap to the Pelvic Autonomic Nerves During Transanal Dissection

Current international guidelines and consensus panels emphasize that nerve sparing is a crucial part of the total mesorectal excision (TME). The transanal approach (taTME) could be advantageous in this regard. However, even with taTME, pelvic autonomic nerve preservation requires perfect knowledge of the topographic and morphological aspects of the anatomy and requires surgeons to acquire specific skills. Unusual surgical topography presents a considerable risk of nerve injury, when attempting a TME with the “bottom-up” approach.

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Validity of Pelvic Autonomic Nerve Stimulation With Intraoperative Monitoring of Bladder Function Following Total Mesorectal Excision for Rectal Cancer

This prospective study was designed to clarify whether the results of the intraoperative stimulation of parasympathetic pelvic nerves performed in 31 patients after mesorectal excision for rectal carcinoma allowed predictions in terms of the postoperative bladder function of the patients.After monopolar stimulation of the splanchnic pelvic nerves using a constant voltage stimulator (Screener 3625), intravesical pressure increase was measured manometrically. The results were related to the postoperative residual urine volume, requirement of recatheterization and long-term catheterization, just as to the results of the validated International Prostatic Symptom Scores and the Quality of Life I…

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Internal anal sphincter nerves - a macroanatomical and microscopic description of the extrinsic autonomic nerve supply of the internal anal sphincter.

Background: The internal anal sphincter (IAS) contributes substantially to anorectal functions. While its autonomic nerve supply has been studied at the microscopic level, little information is available concerning the macroscopic topography of extrinsic nerve fibres. This study was designed to identify neural connections between the pelvic plexus and the IAS, provide a detailed topographical description, and give histological proof of autonomic nerve tissue. Methods: Macroscopic dissection of pelvic autonomic nerves was performed under magnification in seven (5 males, 2 females) hemipelvises obtained from body donors (67-92 years). Candidate structures were investigated by histological and…

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Major urinary dysfunction after mesorectal excision for rectal carcinoma

Abstract Background Urinary dysfunction may occur after mesorectal excision and pelvic autonomic nerve preservation (PANP) in patients with rectal carcinoma. The aim of this prospective study was to identify factors predictive of long-term urinary catheterization. Methods Two hundred and ten patients without significant urological problems underwent resection of rectal cancer with mesorectal excision. The number of patients with complete, partial or no identification of the nerves was documented and correlated with possible predictive factors for postoperative major urinary dysfunction. Results Eight patients (3·8 per cent) required long-term urinary catheterization: two after complete PANP…

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Chirurgische Therapie von Lebermetastasen kolorektaler Karzinome

Resection is the only curative treatment of colorectal liver metastases proofed by a long-term follow-up. The operation is indicated if the metastases are completely removable with sufficient liver parenchyma remaining after resection and if the patient is fit for surgery. The resection is not indicated in cases with non resectable extrahepatic tumours and lymph node metastases distal the hepatoduodenal ligament. The postoperative mortality amounts to about 5 % and the 5-year-survival-rates range between 20 and 40 % depending on the selection of patients. Aims of new concepts of operative therapy are the improvement of resectability by preoperative portal vein embolization, the resection co…

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Randomized clinical trial of prophylactic transanal irrigation versus supportive therapy to prevent symptoms of low anterior resection syndrome after rectal resection

Background Low anterior resection syndrome (LARS) is a frequent problem after rectal resection. Transanal irrigation (TAI) has been suggested as an effective treatment in patients who have developed LARS. This prospective RCT was undertaken to evaluate the effect of TAI as a prophylactic treatment to prevent symptoms of LARS. Methods Patients who had undergone ultralow rectal resection were randomized to start TAI on a daily basis, or to serve as a control with supportive therapy only after ileostomy closure. All patients were seen after 1 week, 1 month and 3 months, and the maximum number of defaecation episodes per day and night documented during follow-up. Wexner score, LARS score and Sh…

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Recurrent laryngeal nerve paralysis (RLNP) following esophagectomy for carcinoma.

Abstract Background The aim of this study was to report the frequency of post-operative recurrent laryngeal nerve paralysis (RLNP) following resection for esophageal carcinoma. Patients and methods Four hundred and four patients were studied. Diagnosis of post-operative RLNP was performed by indirect laryngoscopy. Tumour characteristics, surgical approach and perioperative morbidity and mortality following esophageal resection were recorded. Results Sixty patients were diagnosed with post-operative RLNP, of whom 47 had a unilateral and 16 a bilateral lesion. RLNP was more frequently diagnosed after transhiatal resection with cervical esophagogastrostomy as compared to abdomino-thoracic rese…

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Virtual reality and 3D printing improve preoperative visualization of 3D liver reconstructions-results from a preclinical comparison of presentation modalities and user's preference.

BACKGROUND: Preoperative three-dimensional (3D) reconstructions for liver surgery planning have been shown to be effective in reduction of blood loss and operation time. However, the role of the ‘presentation modality’ is not well investigated. We present the first study to compare 3D PDFs, 3D printed models (PR) and virtual reality (VR) 3D models with regard to anatomical orientation and personal preferences in a high volume liver surgery center. METHODS: Thirty participants, 10 medical students, 10 residents, 5 fellows and 5 hepatopancreatobiliary (HPB) experts, assigned the tumor-bearing segments of 20 different patient’s individual liver reconstructions. Liver models were presented in a…

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Electrical stimulation with motility analysis of five parts of the gastrointestinal tract ; First evaluation of an experimental protocol in a porcine model

Abstract Gastrointestinal (GI) motility disorders are frequent and clinically significant conditions with impairment of patient’s quality of life. Examples range from upper GI symptoms such as dysphagia and gastroparesis to lower GI manifestations, namely chronic-intestinal pseudo obstruction, diarrhea and constipation. Furthermore, postoperative motility disorders are common. Currently, available pharmacological or dietetic treatment options are limited. Since GI motility is based on myoelectric activity, electrical stimulation (ES) is a promising alternative. Numerous studies have demonstrated suitable pacing strategies and parameters in different GI segments. However, results of multiloc…

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Research platform for medical device development to simplify translation to the market

New regulations for medical products complicate research projects for new application fields and translation of innovative product ideas to refundable medical products becomes a high economic risk. All this demands for a CE-marked platform, which offers the possibility to access the recorded data online or even directly the hardware during research applications, to bridge the gap. This paper describes how a CE-marked medical product can be extended by different interfaces to enable basic research or simplify first proof-of-concept studies thus optimizing prototype development in research projects, simplifying the documentation process and reducing the risk for market access.

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Die anteriore Semifundoplicatio — Die Alternative zur Fundoplicatio

Bei der Behandlung der gastroosophagealen Refluxkrankheit (GERD) ist die Semifundoplicatio nach randomisierten Studien mit einer geringeren Dysphagierate im Vergleich zur Fundoplicatio bei vergleichbarer Refluxkontrolle verbunden. Ziel der Studie war es, an einem groseren Krankengut den Einfluss der anterioren Semifundoplicatio bei GERD unter besonderer Berucksichtigung des Langzeitverlaufes aufzuzeigen und damit den Stellenwert als Alternative zur Fundoplicatio nach Nissen zu ermitteln.

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Positronen-Emissions-Tomographie zum präoperativen Staging des Ösophaguskarzinoms

BACKGROUND AND OBJECTIVE Exact preoperative staging is a prerequisite for the indication as well as the choice of the appropriate operative technique for patients with esophageal carcinoma. In this prospective study we assessed whether positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) increases the accuracy of staging compared to standard computer tomography (CT) and leads to a different therapeutic approach. PATIENTS AND METHODS 30 patients (25 men, 5 women, median age 63 years) with histologically identified carcinoma of the esophagus (n =29) and the cardia (n = 1), respectively, were studied. All patients underwent FDG-PET imaging of the neck, chest, and abdomen as w…

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Transanal total mesorectal excision for restorative coloproctectomy in an obese high-risk patient with colitis-associated carcinoma

Transanal total mesorectal excision (TaTME) offers great potential for the treatment of malign and benign diseases. However, laparoscopic-assisted TaTME in ulcerative colitis has not been described in more than a handful of patients. We present a 47-year-old highly comorbid female patient with an ulcerative colitis-associated carcinoma of the ascending colon and steroid- refractory pancolitis. A two-stage restorative coloproctectomy including right-sided complete mesocolic excision was conducted. The second step consisted of a successful nerve-sparing TaTME and a handsewn ileal pouch-anal anastomosis. TaTME may extend the possible treatment options in inflammatory bowel disease, especially …

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Langzeitergebnisse nach Heller-Myotomie mit anteriorer Semifundoplikatio bei Achalasie

INTRODUCTION The positive success rate of cardiomyotomy in the treatment of achalasia has recently - especially in young patients - resulted in a primary operative treatment concept. Few studies of long-term effects of myotomy concerning the removal of dysphagia and the development of gastroesophageal reflux have been submitted. PATIENTS AND METHODS In the period between September 1985 and March 2003, an open, transabdominal Heller-myotomy combined with a Dor-semifundoplication was carried out in 93 patients with achalasia. 77 patients were followed for more than 6 months postoperatively (median follow-up: 70 months). The procedure was prospectively observed, and patients were questioned co…

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Darstellung autonomer Beckennerven bei partieller und totaler Mesorektumexzision

Untersucht werden sollte, wie haufig die autonomen Beckennerven bei totaler Mesorektumexzision (TME) wegen Rektumkarzinom dargestellt und geschont werden konnen und ob ein Zusammenhang mit der postoperativen neurogenen Blasenentleerungsstorung besteht. Zwischen 3/1997 und 2/2003 wurden 229 Patienten bei Adenokarzinom des Rektums operiert. Der Sphinkter wurde bei 178 (78%) der Patienten erhalten. Bei 101 (48%) Erkrankten war der Tumor wandbegrenzt. Fur alle Patienten wurde intraoperativ die Darstellung der Nerven im Verlauf (Plexus hypogastricus superior bis zu den neurovascularen Bundeln) dokumentiert. In multivariater Analyse wurde auf Faktoren mit unabhangigem Einfluss auf Schonung und Da…

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Die operative Therapie einer segmentalen, primären intestinalen Lymphangiektasie des Jejunums mit ausgeprägtem Chylaskos

Primary intestinal lymphangiectasia (PIL) is a protein-losing, exsudative gastroenteropathy causing lymphatic obstruction. Diagnosis depends on clinical examination and histological findings. Conservative treatment modalities include a low-fat diet and enteral nutritional therapy in order to reduce enteric protein loss and to improve fat metabolism. Other treatment options consist of administration of antiplasmin or octreotide to lower lymph flow and secretion. We report on a 58-year-old patient who underwent exploratory laparotomy due to a worsening physical status, recurrent chylaskos and leg oedema under conservative dietary therapy. Intraoperative findings showed a typical PIL of the je…

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Five-fold Gastrointestinal Electrical Stimulation With Electromyography-based Activity Analysis: Towards Multilocular Theranostic Intestinal Implants

Background/aims Motility disorders are common and may affect the entire gastrointestinal (GI) tract but current treatment is limited. Multilocular sensing of GI electrical activity and variable electrical stimulation (ES) is a promising option. The aim of our study is to investigate the effects of adjustable ES on poststimulatory spike activities in 5 GI segments. Methods Six acute porcine experiments were performed with direct ES by 4 ES parameter sets (30 seconds, 25 mA, 500 microseconds or 1000 microseconds, 30 Hz or 130 Hz) applied through subserosal electrodes in the stomach, duodenum, ileum, jejunum, and colon. Multi-channel electromyography of baseline and post-stimulatory GI electri…

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Transcutaneous sacral nerve stimulation for intraoperative verification of internal anal sphincter innervation.

Background: The current standard for pelvic intraoperative neuromonitoring (pIONM) is based on intermittent direct nerve stimulation. This study investigated the potential use of transcutaneous sacral nerve stimulation for non‐invasive verification of pelvic autonomic nerves. Methods: A consecutive series of six pigs underwent low anterior rectal resection. For transcutaneous sacral nerve stimulation, an array of ten electrodes (cathodes) was placed over the sacral foramina (S2 to S4). Anodes were applied on the back, right and left thigh, lower abdomen, and intra‐anally. Stimulation using the novel method and current standard were performed at different phases of the experiment…

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An Interactive Demonstration of Collaborative VR for Laparoscopic Liver Surgery Training

We introduce a collaborative virtual reality (VR) system for planning and simulation in laparoscopic liver surgery training. Patient image data is used for surgical model visualization and simulation. We developed two modes for training in laparoscopic procedures: exploration and surgery mode. Surgical joysticks are used in surgery mode to provide training for psychomotor skills and cooperation between a camera assistant and an experienced surgeon. Continuous feedback from our clinical partner comprised an important part of the development. Our evaluation showed that surgeons were positive about the usability and usefulness of the developed system. For further details, please refer to our f…

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Is intraoperative neuromonitoring associated with better functional outcome in patients undergoing open TME?

Aims: Intraoperative neuromonitoring (IONM) aims to control nerve-sparing total mesorectal excision (TME) for rectal cancer in order to improve patients’ functional outcome. This study was designed to compare the urogenital and anorectal functional outcome of TME with and without IONM of innervation to the bladder and the internal anal sphincter. Methods: A consecutive series of 150 patients with primary rectal cancer were analysed. Fifteen match pairs with open TME and combined urogenital and anorectal functional assessment at follow up were established identical regarding gender, tumour site, tumour stage, neoadjuvant radiotherapy and type of surgery. Urogenital and anorectal function was…

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Individualisierte Chirurgie bei Rektumkarzinomen

Die anteriore oder tiefe anteriore Rektumresektion in Kombination mit einer partiellen (PME) oder totalen mesorektalen Exzision (TME) sind die derzeitigen Standardverfahren in der Chirurgie der Rektumkarzinome. Diese Operationen werden laparoskopisch oder in konventioneller Technik durchgefuhrt. Die wesentlichen Phasen der Operation sind: 1. Mobilisierung von Sigma und Colon descendens; 2. Durchtrennung der A. und V. mesenterica inferior; 3. Durchtrennung des Colon descendens; 4. Mobilisierung des Rektums in PME- oder TME-Technik; 5. Absetzen des Rektums; 6. Anastomosierung; 7. Anlage eines protektiven Stomas (optional). Technische Probleme und schwierige Entscheidungssituationen entstehen …

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Persistierende und rezidivierende Schluckstörung nach Operation bei Achalasie — Ursache und Behandlung

Die operative Therapie bei Achalasie fuhrt zu lang andauernder Beschwerdefreiheit. Selten persistieren die Beschwerden oder es treten im Verlauf erneute schwere Schluckstorungen auf. Ziel vorliegender Untersuchung war die Erfassung der Ursache und Therapie des Rezidivs sowie die Darstellung der Ergebnisse nach einer erneuten Operation. Patienten und Methode: Unter 83 Patienten mit Achalasie wurden 11 seit 1985 wegen persistierender oder erneuter Schluckbeschwerden wiederholt operiert. Die Patienten im Alter zwischen 19 und 77 Jahren waren bereits durch Kardiomyotomie behandelt. Die Anamnesedauer lag zwischen 12 Monaten und 42 Jahren. Vor der Zweitoperation litten alle Erkrankten unter Dysph…

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3D-Druck, Virtual Reality oder regulärer Monitor? Vergleich unterschiedlicher Darstellungsmöglichkeiten dreidimensionaler Leberrekonstruktionen

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Intraoperative identification and neurophysiologic parameters to verify pelvic autonomic nerve function during total mesorectal excision for rectal cancer.

Abstract Background Preservation of parasympathetic and sympathetic nerves is required to avoid urogenital function disturbances after total mesorectal excision (TME) for rectal carcinoma. This study sought to determine whether intraoperative stimulation of parasympathetic nerves with monitoring of bladder contraction is useful in meeting this demand. Study design In a prospective pilot study, 17 patients, 11 men and 6 women, underwent TME with pelvic autonomic nerve preservation performed by an experienced surgeon. The parasympathetic nerves were stimulated by an electrostimulation device (Screener 3625, Medronic), and the resulting bladder contraction was measured manometrically in all pa…

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Positronen-Emissions-Tomographie in der präoperativen Diagnostik des ösophaguskarzinoms — Erste Ergebnisse einer prospektiven Studie

Voraussetzung fur die Indikation zur Operation bei osophaguskarzinom und die Wahl des geeigneten Operationsverfahrens ist ein genaues praoperatives Staging. Ziel vorliegender prospektiver Studie war es zu klaren, ob eine Positronen-Emissions-Tomographie mit 18F-Fluoro-deoxyglucose (FDG-PET) bei Patienten mit Osophaguskarzinom die Genauigkeit des praoperatives Stagings gegenuber der Computertomographie (CT) von Thorax und Abdomen erhoht und zu therapeutischen Konsequenzen fuhrt. Patienten und Methode: Von Januar bis September 2001 erhielten 32 Patienten bei histologisch gesichertem Osophaguskarzinom ein FDG-PET von Hals Thorax und Abdomen und ein CT von Thorax und Abdomen im Rahmen des praop…

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Extracorporeal Stimulation of Sacral Nerve Roots for Observation of Pelvic Autonomic Nerve Integrity: Description of a Novel Methodological Setup.

Introduction: Neurophysiologic monitoring can improve autonomic nerve sparing during critical phases of rectal cancer surgery. Objectives: To develop a system for extracorporeal stimulation of sacral nerve roots. Methods: Dedicated software controlled a ten-electrode stimulation array by switching between different electrode configurations and current levels. A built-in impedance and current level measurement assessed the effectiveness of current injection. Intra-anal surface electromyography (sEMG) informed on targeting the sacral nerve roots. All tests were performed on five pig specimens. Results: During switching between electrode configurations, the system delivered 100% of the set cur…

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Pelvic Autonomic Nerve Preservation during Total Mesorectal Excision (TME) from Werner Kneist

According to the German guideline for “Colorectal Cancer,” total mesorectal excision (TME) removes the cancer located at the central and lower thirds of the rectum and the pelvic floor while preserving the superior hypogastric plexus (SHP), the hypogastric nerves, and the inferior hypogastric plexus (IHP) (recommendation level A, level of evidence 1b, strong consensus). Intraoperative nerve damage is to be avoided to preserve postoperative quality of life with the premise of radical surgery. It is particularly necessary to preserve autonomously controlled urogenital and anorectal functions. Among other things, this presumes a fundamental understanding of current events on surgical topograph…

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Surgeons’ assessment of internal anal sphincter nerve supply during TaTME - inbetween expectations and reality

Abstract Background: Intraoperative identification of nerve fibers heading from the inferior rectal plexus (IRP) to the internal anal sphincter (IAS) is challenging. The transanal total mesorectal excision (TaTME) is said to better preserve pelvic autonomic nerves. The aim of this study was to investigate the nerve identification rates during TaTME by transanal visual and electrophysiological assessment. Material and methods: A total of 52 patients underwent TaTME for malignant conditions. The IRP with its posterior branches to the IAS and the pelvic splanchnic nerves (PSN) were visually assessed in 20 patients (v-TaTME). Electrophysiological nerve identification was performed in 32 patient…

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Online signal processing of internal anal sphincter activity during pelvic autonomic nerve stimulation: a new method to improve the reliability of intra-operative neuromonitoring signals

Aim  Intra-operative neuromonitoring is increasingly applied in several surgical disciplines and has been introduced to facilitate pelvic autonomic nerve preservation. Nevertheless, it has been considered a questionable tool for the minimization of risk, as the results are variable and might be misleading. The aim of the present experimental study was to develop an intra-operative neuromonitoring system with improved reliability for monitoring pelvic autonomic nerve function. Method  Fifteen pigs underwent low anterior rectal resection with pelvic autonomic nerve preservation. Intra-operative neuromonitoring was performed under autonomic nerve stimulation with observation of electromyograph…

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Positron Emission Tomography for Staging Esophageal Cancer: Does It Lead to a Different Therapeutic Approach?

Accurate preoperative staging is essential for the indication and selection of the appropriate surgical procedure in patients with esophageal cancer. The present prospective study was designed to determine if the preoperative use of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) increases the accuracy of staging esophageal cancer compared with computed tomography (CT) and if it thereby leads to a different therapeutic approach. A total of 58 patients, 46 men and 12 women (mean age 61 years), with histologic proof of esophageal carcinoma underwent FDG-PET of the neck, chest, and abdomen, as well as CT of the chest and abdomen, to determine tumor stage. FDG-PET and CT data we…

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How to Report on Distal Resection Margins in Trials on Rectal Cancer Surgery

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Quality-based assessment of camera navigation skills for laparoscopic fundoplication.

Summary Laparoscopic fundoplication is considered the gold standard surgical procedure for the treatment of symptomatic hiatus hernia. Studies on surgical performance in minimally invasive hiatus hernia repair have neglected the role of the camera assistant so far. The current study was designed to assess the applicability of the structured assessment of laparoscopic assistance skills (SALAS) score to laparoscopic fundoplication as an advanced and commonly performed laparoscopic upper GI procedure. Randomly selected laparoscopic fundoplications (n = 20) at a single institute were evaluated. Four trained reviewers independently assigned SALAS scoring based on synchronized video and voice rec…

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Total mesorectal excision - does the choice of dissection technique have an impact on pelvic autonomic nerve preservation?

Background The aim of this experimental study was to assess the quality of pelvic autonomic nerve preservation of different dissection techniques.

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Collaborative Virtual Reality for Laparoscopic Liver Surgery Training

Virtual reality (VR) has been used in many medical training systems for surgical procedures. However, the current systems are limited due to inadequate interactions, restricted possibilities of patient data visualization, and collaboration. We propose a collaborative VR system for laparoscopic liver surgical planning and simulation. Medical image data is used for model visualization and manipulation. Additionally, laparoscopic surgical joysticks are used to provide an opportunity for a camera assistant to cooperate with an experienced surgeon in VR. Continuous clinical feedback led us to optimize the visualization, synchronization, and interactions of the system. Laparoscopic surgeons were …

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Selektion von Patienten mit Rektumtumoren zur lokalen Exzision aufgrund der pr�operativen Diagnostik

Ziel unserer Studie war die Erfassung der Genauigkeit der praoperativen Diagnostik (rektal-digitale Untersuchung, Biopsie und transanale Endosonographie) bei durch lokale Exzision behandelten Rektumtumoren. 552 Patienten mit Rektumkarzinom, Adenom, Karzinoiden oder seltenen benignen Tumoren wurden lokal exzidiert. Die Ergebnisse der rektal-digitalen Untersuchung, der Biopsie und der transanalen Endosonographie wurden mit dem postoperativen pathohistologischen Befund verglichen. Der praoperative histologische Nachweis des Karzinoms ist abhangig von der Tumorgrose (52% bei Karzinomen 3 cm; p=0,001) und war korrekt in 56% aller Karzinome. Die transanale Endosonographie (uT0/1) ist sensitiver (…

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Ist die transhiatale Oesophagusresektion mit unterer posteriorer mediastinaler sowie abdomineller Lymphknotendissektion onkologisch ausreichend beim distalen Plattenepithelkarzinom des Oesophagus

Einleitung: Die transhiatale Oesophagusresektion wird aus onkologischer Sicht aufgrund der eingeschrankteren Moglichkeit einer mediastinalen Lymphknotendissektion haufig als palliative Therapie des Plattenepithelkarzinom des Oesophagus angesehen im Gegensatz zur abdominothorakalen Oesophagusresektion mit 2- oder 3-Feld Lymphknotendissektion. Andererseits kann auch im Rahmen einer transhiatalen Resektion eine Lymphknotendissektion des unteren posterioren Mediastinums bis zur Trachealbifurkation durchgefuhrt werden, so dass bei distaler Tumorlokalisation das transhiatale Vorgehen moglicherweise vertretbar erscheint. Ziel dieser Analyse des eigenen Krankenguts war es, den Langzeitverlauf der P…

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Influence of identification and preservation of pelvic autonomic nerves in rectal cancer surgery on bladder dysfunction after total mesorectal excision.

PURPOSE: Given the improvement in oncologic outcome after the introduction of total mesorectal excision for the treatment of rectal cancer, the objective of the present study was to determine the frequency of identification and preservation of the pelvic autonomic nerves and to identify a possible link between postoperative micturition disturbances and the extent of the radical resection. METHODS: Between March 1997 and December 2001, 150 patients with adenocarcinoma of the rectum (≤16 cm from the anal verge) underwent surgery, with sphincter preservation in 112 cases (74.7 percent). Sixty-three patients (42 percent) were classified as American Society of Anesthesiologists Stage III and two…

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Die Positronenemissionstomographie zur pr�operativen Lymphknotendiagnostik bei �sophaguskarzinom

Vorraussetzung fur Indikation und Wahl des geeigneten operativen Verfahrens bei Patienten mit Osophaguskarzinom ist ein genaues praoperatives Staging. Ziel der prospektiven Studie war es, zu klaren, ob eine Positronenemissionstomographie mit 18F-Fluoro-Deoxyglukose (FDG-PET) die Genauigkeit des praoperativen Lymphknotendiagnostik gegenuber der Computertomographie (CT) erhoht und die Wahl des operativen Zugangs zur Osophagusresektion beeinflusst. 58 Patienten, 46 Manner und 12 Frauen (Alter 61 Jahre im Mittel), erhielten bei histologisch gesichertem Osophaguskarzinom im Rahmen des Stagings ein FDG-PET von Hals, Thorax und Abdomen sowie ein CT von Thorax und Abdomen. Sensitivitat, Spezifitat …

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Translational development and pre-clinical evaluation of prototype gastrointestinal mock-up devices: only robotic placement of plastic?

Background: The aim of this study was to address the vision of wireless theranostic devices distributed along the gastrointestinal (GI) tract by defining design requirements, developing prototype mock-ups, and establishing a minimally invasive surgical approach for the implantation process. Methods: Questionnaires for contextual analysis and use case scenarios addressing the technical issues of an implantable GI device, a possible scenario for implantation, preparation and calibration of a device, and therapeutic usage by professionals and patients were completed and discussed by an interdisciplinary team of surgeons, engineers, and product designers. Two acute porcine experiments were cond…

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Chirurgische Anatomie und neurophysiologische Parameter zur intraoperativen Identifikation und Funktionsprüfung autonomer Beckennerven bei TME wegen Rektumkarzinom

Introduction The identification and preservation of parasympathetic and sympathetic pelvic nerves is required to avoid urogenital malfunctions after TME for rectal carcinoma. The objective was to determine the surgical topography of the nerves with regard to TME. Neurophysiologiecl parameters for the intraoperative stimulation of the detrusor muscle were assessed in order to establish a functional test for the intraoperative identification of the pelvic autonomic nerves.

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Technical Alternatives in Laparoscopic Placement of an Adjustable Gastric Band: Experience of Two German University Hospitals

Background: The technique of laparoscopic adjustable gastric banding (LAGB), although relatively well standardized, has some "weak points". Methods: We analysed the experience of 2 German university clinics in order to suggest technical alternatives that can be helpful in difficult situations. Results: Between April 1997 and May 2002 115 patients in Cologne (87 females, 28 males) with median BMI 49.5 kg/m2 and mean age 39 years (19-54), and 112 patients in Mainz (91 females, 21 males) with median BMI 48 kg/m2 and mean age 35 years (18-57) underwent LAGB, using the Lap-Band®. LAGB was performed through 5 ports (3 10-mm, 1 18-mm, and 1 5-mm in Cologne and 4 10-mm and 1 18-mm port in Mainz). T…

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Head-Mounted Mixed-Reality Technology During Robotic-Assisted Transanal Total Mesorectal Excision

INTRODUCTION Head-mounted mixed-reality technologies may enable advanced intraoperative visualization during visceral surgery. In this technical note, we describe an innovative use of real-time mixed reality during robotic-assisted transanal total mesorectal excision. TECHNIQUE Video signals from the robotic console and video endoscopic transanal approach were displayed on a virtual monitor using a head-up display. The surgeon, assistant, and a surgical trainee used this technique during abdominal and transanal robotic-assisted total mesorectal excision. We evaluated the feasibility and usability of this approach with the use of validated scales. RESULTS The technical feasibility of the rea…

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Continuous intraoperative monitoring of pelvic autonomic nerves as a microtechnological navigation instrument

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Local excision for more advanced rectal tumors

Over the past 20 years, local excision (LE) of T1 rectal cancer was increasingly established and represents an oncologically established technique. In contrast, the situation for T2 tumors is less clear and has only been investigated in small patient collectives. LE for T2 tumors is thus discussed controversially.In addition to our own patients with T2 rectal cancer treated locally (n=40), we have analysed the local recurrence (LR) rates after LE alone (n=124), after immediate conventional radical reoperation (n=29), after adjuvant (chemo)-radiotherapy (n=294) and those after neoadjuvant chemoradiotherapy (nCRT) (n=269) using a PubMed search.LR rates of low-grade T2 tumors after R0 resectio…

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Die laterale Dissektion des Mesorektums ; ein Risiko für den Plexus hypogastricus inferior

Lateral mesorectal dissection may injure parasympathetic and sympathetic pelvic nerves and a partial or complete lesion of the autonomic pelvic nerves leads to urogenital dysfunctions affecting patient’s quality of life after rectum resection for rectal carcinoma. The aim of the present prospective study was to clarify the significance for nerve damage during lateral dissection based on standardized assessment parameters. 15 Patients underwent total mesorectal excision for rectal carcinoma (UICC I/II/III/IV: 1/5/3/6). Within the scope of the stanardized intraoperative data collection it was demonstrated, whether a complete preservation of the autonomie pelvic nerves was successful. In 11 pa…

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Laparoscopic assistance by operating room nurses: Results of a virtual-reality study

Abstract Background Laparoscopic assistance is often entrusted to a less experienced resident, medical student, or operating room nurse. Data regarding laparoscopic training for operating room nurses are not available. Objectives The aim of the study was to analyse the initial performance level and learning curves of operating room nurses in basic laparoscopic surgery compared with medical students and surgical residents to determine their ability to assist with this type of procedure. Design The study was designed to compare the initial virtual reality performance level and learning curves of user groups to analyse competence in laparoscopic assistance. Participants The study subjects were…

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Innervation der subperitonealen Beckenetage: Möglichkeiten zur Optimierung der Rektumchirurgie

Einleitung: Bei totaler mesorektaler Exzision (TME) soll die Rate postoperativer urogenitaler Funktionsstorungen durch genauere topographische Kenntnisse von Faszien- und Nervenverlaufen weiter abgesenkt werden. Methodik: An 10 anatomischen Korperspenden wurden makroskopische Praparationen, schnittanatomische Studien, histologische und immunhistochemische Untersuchungen sowie Morphometrien durchgefuhrt. Es wurden Faszienverhaltnisse und Nervenverlaufe analysiert. Ergebnisse: Die neurovaskularen Bundel zeigen als Auslaufer des Plexus hypo gastricus inferior die Hochste Dichte von Nervengewebe. Am lateralen Rand der Denonvilliers-Faszie treten sie unter der Fascia pelvis parietalis hervor. Za…

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Anterior partial fundoplication for gastroesophageal reflux disease.

This study examined the effect of anterior partial fundoplication on reflux symptoms and dysphagia in gastroesophageal reflux disease. Perioperative results in 249 patients were evaluated retrospectively for 93 conventional and prospectively for 156 laparoscopic procedures. The patients were followed up by standardized questionnaire. Median clinical follow-up period was 9 months (range 6–44) after laparoscopic and 88 months (range 15–194) following partial open fundoplication. The median operating time was 58 and 115 min for laparoscopic and open partial fundoplication. Intraoperative complications were rare (1%) for both approaches. After introduction of the laparoscopic procedure the morb…

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Management of Bleeding Complications in Virtual Reality Laparoscopy

The aim of this study was to compare the impact of induced bleeding complication training with regular training on a virtual reality laparoscopic (VRL) simulator. Although bleeding complications occur rarely during laparoscopic surgery, they usually arise without warning and may have severe consequences for the patient because complication management training is not currently widespread. Third-year medical students (n = 41) were randomly selected for 2 curricular courses on how to perform a bimanual task on a VRL simulator. Both the regular training group (RTG) and the induced bleeding complication training (ICT) group performed 2 regular training sessions and 9 training sessions. For the I…

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Differences in ano-neorectal physiology of ileoanal and coloanal reconstructions for restorative proctectomy

Objective  Restorative proctectomy with straight coloanal anastomosis (CAA) and restorative proctocolectomy with ilealpouch-anal anastomosis (IPAA) are options for maintaining bowel integrity after rectal resection. The aim of this study was to compare clinical function and anorectal physiology in patients treated with CAA and IPAA. Method  Three-dimensional vector-manometry and neorectal volumetry were performed in straight CAA [53 patients (34 male)] and IPAA [61 patients (39 male)] for ulcerative colitis. Function was assessed using a 14 day incontinence diary. Results  Function was similar in both groups, but neorectal compliance and threshold volumes for sensation, urge and maximum tol…

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Total mesorectal excision with intraoperative assessment of internal anal sphincter innervation provides new insights into neurogenic incontinence

Background: The aim of this prospective study was to assess internal anal sphincter (IAS) innervation in patients undergoing total mesorectal excision (TME) by intraoperative neuromonitoring (IONM). Study Design: Fourteen patients underwent TME. IONM was carried out through pelvic splanchnic nerve stimulation under continuous electromyography of the IAS. Anorectal function was assessed with the digital rectal examination scoring system and a standardized questionnaire. Results: Nine of 11 patients who underwent low anterior resection had positive IONM results, with stimulation-induced increased IAS electromyographic amplitudes (median 0.23 V (interquartile range [IQR] 0.05, 0.56) vs median …

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Intraoperative Monitoring of Bladder and Internal Anal Sphincter Innervation: A Predictor of Erectile Function following Low Anterior Rectal Resection for Rectal Cancer? Results of a Prospective Clinical Study

<b><i>Background:</i></b> The objective was to investigate whether two-dimensional intraoperative neuromonitoring (IONM) of pelvic autonomic nerves has the potential to predict erectile function (EF) following surgery for rectal cancer. <b><i>Methods:</i></b> A consecutive series of 17 sexually active male rectal cancer patients undergoing IONM-based nerve-sparing low anterior rectal resection were evaluated prospectively. IONM was performed by electric stimulation of the pelvic splanchnic nerves with concomitant electromyography of the internal anal sphincter and cystomanometry. Sexual function was assessed using a validated questionnaire. &l…

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Prätherapeutische Selektion von Patienten mit Rektumkarzinom zur lokalen Excision

Ziel einer retrospektiven Analyse des eigenen Krankengutes war die Klarung der Frage, wie oft sich die Indikationsstellung zur lokalen Excsion von Rektumtumoren anhand des postoperativen pathohistologischen Befundes als adaquate Therapiemasnahme erweist und wie oft sie lediglich eine diagnostische Masnahme darstellt.

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Robotic Setup Promises Consistent Effects of Multilocular Gastrointestinal Electrical Stimulation: First Results of a Porcine Study

<b><i>Background:</i></b> Electrical stimulation (ES) of several gastrointestinal (GI) segments is a promising therapeutic option for multilocular GI dysmotility, but conventional surgical access by laparotomy involves a high degree of tissue trauma. We evaluated a minimally invasive surgical approach using a robotic surgical system to perform electromyographic (EMG) recordings and ES of several porcine GI segments, comparing these data to an open surgical approach by laparotomy. <b><i>Materials and Methods:</i></b> In 5 acute porcine experiments, we placed multiple electrodes on the stomach, duodenum, jejunum, ileum, and colon. Three experime…

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Identifikation und Schonung der autonomen Beckennerven bei TME durch selektive Nervenstimulation

Zur Vermeidung urologenitaler Funktionsstorungen nach Totaler Mesorektum Exzision (TME) bei Rektumkarzinom mussen die autonomen Beckennerven identifiziert und geschont (PANP) werden, was insbesondere fur die parasympathischen Anteile im tiefen Becken problematisch ist. In einer prospektiven Studie sollte gepruft werden, ob die intraoperative Stimulation der zur Blase ziehenden Aste bzw. des Plexus hypogastricus inferior geeignet ist autonome Beckennerven zu identifizieren und ihre Funktionsfahigkeit zu erhalten.

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Motility analysis by means of video tracked markers

Abstract The motility of the gastrointestinal tract is crucial for digestive activity and dysfunction can lead to severe disease pattern. A method for analysing the motility is needed when treatment approaches shall be evaluated. Therefore markers attached to different locations on the stomach and the bowel of pigs are video tracked in this research study. The markers are designed to provide a high contrast and have an adhesive side for fixation. Above the operation field a video camera has been placed to film the markers during the procedure. To analyse the video data a special algorithm has been implemented. The algorithm requires a registration process at the beginning of each recording …

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Anatomie und Schonung der autonomen Nerven im Becken

Vor dem Hintergrund der verbesserten Prognose nach kurativ intendierter Behandlung von Patienten mit primarem Rektumkarzinom rucken in der modernen Chirurgie konsequenterweise funktionelle, die Lebensqualitat bestimmende Aspekte in den Fokus. So sollen mit einer sogenannten nervenschonenden Operation uber das autonome Nervensystem gesteuerte urogenitale und anorektale Funktionen in hoherem Mase erhalten werden. Fachpublikationen, Leitlinien, standardisierte Aufklarungsbogen, Krankenkassen, Selbsthilfegruppen, die mediale Offentlichkeit aber auch Fachanwalte und Gutachter greifen diesen Themenkomplex, seiner Bedeutung fur die Patienten entsprechend, auf. In diesem Kapitel wird aus operativer…

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Surface Electromyography Reliably Records Electrophysiologically Evoked Internal Anal Sphincter Activity: A More Minimally Invasive Approach for Monitoring Extrinsic Innervation.

<b><i>Background:</i></b> Even in the case of minimally invasive pelvic surgery, sparing of the autonomic nerve supply is a prerequisite for maintaining anal sphincter function. Internal anal sphincter (IAS) innervation could be electrophysiologically identified based on processed electromyographic (EMG) recordings with conventional bipolar needle electrodes (NE). This experimental study aimed for the development of a minimally invasive approach via intra-anal surface EMG for recordings of evoked IAS activity. <b><i>Methods:</i></b> Six male pigs underwent nerve-sparing low anterior rectal resection. Electric autonomic nerve stimulations were …

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Artificial Versus Video-Based Immersive Virtual Surroundings: Analysis of Performance and User's Preference.

Introduction. Immersive virtual reality (VR) laparoscopy simulation connects VR simulation with head-mounted displays to increase presence during VR training. The goal of the present study was the comparison of 2 different surroundings according to performance and users’ preference. Methods. With a custom immersive virtual reality laparoscopy simulator, an artificially created VR operating room (AVR) and a highly immersive VR operating room (IVR) were compared. Participants (n = 30) performed 3 tasks (peg transfer, fine dissection, and cholecystectomy) in AVR and IVR in a crossover study design. Results. No overall difference in virtual laparoscopic performance was obtained when comparing …

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Robot-assisted minimally invasive esophagectomy (RAMIE) compared to conventional minimally invasive esophagectomy (MIE) for esophageal cancer: a propensity-matched analysis.

SUMMARY Robot-assisted minimally invasive esophagectomy (RAMIE) is increasingly being applied as treatment for esophageal cancer. In this study, the results of 50 RAMIE procedures were compared with 50 conventional minimally invasive esophagectomy (MIE) operations, which had been the standard treatment for esophageal cancer prior to the robotic era. Between April 2016 and March 2018, data of 100 consecutive patients with esophageal carcinoma undergoing modified Ivor Lewis esophagectomy were prospectively collected. All operations were performed by the same surgeon using an identical intrathoracic anastomotic reconstruction technique with the same perioperative management and pain control re…

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Residual urine volume after total mesorectal excision: an indicator of pelvic autonomic nerve preservation? Results of a case-control study.

Objective  The rate of bladder dysfunctions after total mesorectal excision (TME) for rectal cancer can be decreased by bilateral pelvic autonomic nerve preservation (PANP). However, it is not clear yet, how often partial nerve impairment may lead to bladder dysfunction. It was the aim of a case-control study, to examine the residual urine volume in patients before and after TME with and without complete PANP, in order to clarify, whether this parameter allows conclusions on the quality of PANP. Patients and methods  Regarding bladder function, a case group (n = 26) without complete PANP was compared with a control group (n = 26) with complete identification and nerve preservation according…

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Postprocessing algorithm for automated analysis of pelvic intraoperative neuromonitoring signals

Abstract Two dimensional pelvic intraoperative neuromonitoring (pIONM®) is based on electric stimulation of autonomic nerves under observation of electromyography of internal anal sphincter (IAS) and manometry of urinary bladder. The method provides nerve identification and verification of its’ functional integrity. Currently pIONM® is gaining increased attention in times where preservation of function is becoming more and more important. Ongoing technical and methodological developments in experimental and clinical settings require further analysis of the obtained signals. This work describes a postprocessing algorithm for pIONM® signals, developed for automated analysis of huge amount of …

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Translational development and pre-clinical evaluation of prototype gastrointestinal mock-up devices: only robotic placement of plastic?

Background: The aim of this study was to address the vision of wireless theranostic devices distributed along the gastrointestinal (GI) tract by defining design requirements, developing prototype mock-ups, and establishing a minimally invasive surgical approach for the implantation process. Methods: Questionnaires for contextual analysis and use case scenarios addressing the technical issues of an implantable GI device, a possible scenario for implantation, preparation and calibration of a device, and therapeutic usage by professionals and patients were completed and discussed by an interdisciplinary team of surgeons, engineers, and product designers. Two acute porcine experiments were cond…

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