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Dive into the research topics where Neil Mortensen is active.

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Featured researches published by Neil Mortensen.


Annals of Surgery | 2017

Transanal Total Mesorectal Excision: International Registry Results of the First 720 Cases

Marta Penna; Roel Hompes; Steve Arnold; Greg Wynn; Ralph Austin; Janindra Warusavitarne; Brendan Moran; George B. Hanna; Neil Mortensen; Paris P. Tekkis

Objective: This study aims to report short-term clinical and oncological outcomes from the international transanal Total Mesorectal Excision (taTME) registry for benign and malignant rectal pathology. Background: TaTME is the latest minimally invasive transanal technique pioneered to facilitate difficult pelvic dissections. Outcomes have been published from small cohorts, but larger series can further assess the safety and efficacy of taTME in the wider surgical population. Methods: Data were analyzed from 66 registered units in 23 countries. The primary endpoint was “good-quality TME surgery.” Secondary endpoints were short-term adverse events. Univariate and multivariate regression analyses were used to identify independent predictors of poor specimen outcome. Results: A total of 720 consecutively registered cases were analyzed comprising 634 patients with rectal cancer and 86 with benign pathology. Approximately, 67% were males with mean BMI 26.5 kg/m2. Abdominal or perineal conversion was 6.3% and 2.8%, respectively. Intact TME specimens were achieved in 85%, with minor defects in 11% and major defects in 4%. R1 resection rate was 2.7%. Postoperative mortality and morbidity were 0.5% and 32.6% respectively. Risk factors for poor specimen outcome (suboptimal TME specimen, perforation, and/or R1 resection) on multivariate analysis were positive CRM on staging MRI, low rectal tumor <2 cm from anorectal junction, and laparoscopic transabdominal posterior dissection to <4 cm from anal verge. Conclusions: TaTME appears to be an oncologically safe and effective technique for distal mesorectal dissection with acceptable short-term patient outcomes and good specimen quality. Ongoing structured training and the upcoming randomized controlled trials are needed to assess the technique further.


Annals of Surgery | 2013

Waist Circumference and Waist/Hip Ratio Are Better Predictive Risk Factors for Mortality and Morbidity after Colorectal Surgery Than Body Mass Index and Body Surface Area

Alex Kartheuser; Daniel Léonard; Hugh Paterson; Dimitri Brandt; Christophe Remue; Céline Bugli; Eric J. Dozois; Neil Mortensen; Frédéric Ris; Emmanuel Tiret

Objectives:To determine whether body fat distribution, measured by waist circumference (WC) and waist/hip ratio (WHR), is a better predictor of mortality and morbidity after colorectal surgery than body mass index (BMI) or body surface area (BSA). Background:Obesity measured by BMI is not a consistent risk factor for postoperative mortality and morbidity after abdominal surgery. Studies in metabolic and cardiovascular diseases have shown WC and WHR to be better outcome predictors than BMI. Methods:A prospective multicenter international study was conducted among patients undergoing elective colorectal surgery. The WHR, BMI, and BSA were derived from body weight, height, and waist and hip circumferences measured preoperatively. Uni- and multivariate analyses were performed to identify risk factors for postoperative outcomes. Results:A total of 1349 patients (754 men) from 38 centers in 11 countries were included. Increasing WHR significantly increased the risk of conversion [odds ratio (OR) = 15.7, relative risk (RR) = 4.1], intraoperative complications (OR = 11.0, RR = 3.2), postoperative surgical complications (OR = 7.7, RR = 2.0), medical complications (OR = 13.2, RR = 2.5), anastomotic leak (OR = 13.7, RR = 3.3), reoperations (OR = 13.3, RR = 2.9), and death (OR = 653.1, RR = 21.8). Both BMI (OR = 39.5, RR = 1.1) and BSA (OR = 4.9, RR = 3.1) were associated with an increased risk of abdominal wound complication. In multivariate analysis, the WHR predicted intraoperative complications, conversion, medical complications, and reinterventions, whereas BMI was a risk factor only for abdominal wall complications; BSA did not reach significance for any outcome. Conclusions:The WHR is predictive of adverse events after elective colorectal surgery. It should be used in routine clinical practice and in future risk-estimating systems.


Colorectal Disease | 2013

Completion surgery following transanal endoscopic microsurgery: assessment of quality and short- and long-term outcome.

Roel Hompes; R. McDonald; C. Buskens; I. Lindsey; N. C. Armitage; Jonathan Hill; A. Scott; Neil Mortensen; C. Cunningham

Patients with unfavourable pathology after transanal endoscopic microsurgery (TEM) should be offered completion surgery (CS) if appropriate. The aim of this retrospective cohort study was to assess the short‐term outcome and long‐term oncological results of CS and identify factors compromising the quality of resection specimens.


Diseases of The Colon & Rectum | 1996

Nitrergic innervation and relaxant response of rectal circular smooth muscle.

John F. Stebbing; Alison F. Brading; Neil Mortensen

PURPOSE: This study was designed to investigate whether nitric oxide mediates inhibitory innervation in human rectal circular smooth muscle. METHODS: Tissue was obtained from the midrectum of patients undergoing anterior resection for carcinoma. Adjacent strips of circular muscle were dissected and mounted in superfusion organ baths for isometric tension recording and initially loaded with 1 g of weight. Strips were continuously bathed with standard Krebs solution (37°C, bubbled with 97 percent O2/3 percent CO2) containing 3×10−6M guanethidine and 3×10−6M atropine sulfate to block adrenergic and muscarinic cholinergic neurotransmission. After equilibration, strips had no intrinsic tone, and reproducible and stable tension was, therefore, induced by the addition of 3×10−6M histamine for five-minute “test” periods, during which electrical field stimulation (EFS) and additional drugs were applied. RESULTS: EFS elicited frequency-dependent, neurogenic (tetrodotoxin-sensitive) relaxations of precontracted strips. Addition ofN-ω-nitro-l-arginine, a powerful competitive inhibitor of nitric oxide synthase, reduced the relaxant response to EFS in a dose-dependent fashion, an effect reversed by addition of 3×10−4Ml-arginine but not by D-arginine. Addition of exogenous nitric oxide (sodium nitroprusside) mimicked the relaxant response induced by EFS. CONCLUSIONS: Human rectal circular smooth muscle receives an intrinsic inhibitory innervation mediated by nitric oxide. The presence of a residual response following blockade of the enzyme nitric oxide synthase suggests the involvement of additional neurotransmitters.


Journal of Crohns & Colitis | 2013

Outcomes after ileal pouch anal anastomosis in patients with primary sclerosing cholangitis

Michael Pavlides; Jon Cleland; Monira Rahman; Annabel Christian; Jennifer Doyle; Robert E. Gaunt; Simon Travis; Neil Mortensen; Roger W. Chapman

BACKGROUND AND AIMS Outcomes after ileal pouch anal anastomosis (IPAA) are not well established in patients with primary sclerosing cholangitis (PSC). We conducted a comprehensive outcomes assessment in these patients. METHODS A retrospective case note review of complications in all PSC-IPAA (n=21) and matched ulcerative colitis patients with IPAA (UC-IPAA; n=79) after surgery in Oxford (1983-2012) was conducted, and functional outcomes (Öresland score) were evaluated (2012). Quality of life [Cleveland Global Quality of Life Questionnaire, Short Form-36 (SF-36)], and sexual function were also assessed (2012) including patients with PSC-associated UC without IPAA (PSC-UC; n=19). Sub-group analysis of patients with large duct (ld) PSC-IPAA (n=17) was also performed. RESULTS The 1-, 5-, 10- and 20-year risk of acute pouchitis for PSC-IPAA was 10%, 19%, 31% and 65% respectively, compared to 3%, 10%, 14% and 28% in UC-IPAA (p=0.03). More PSC-IPAA (36%) had poor nocturnal pouch function (vs 2% in UC-IPAA; p=0.0016). There were no differences in surgical complications, quality of life or sexual function between the 3 main groups. LdPSC-IPAA had poorer pouch function (Öresland score: 7.7 vs 5.4 in UC-IPAA; p=0.02), and worse quality of life [SF-36 Physical: 42 vs 50.5 in UC-IPAA; 47.7 in PSC-UC; p=0.03 and Mental Health summary scores: 41.6 vs 51.2 in UC-IPAA; 42.3 in PSC-UC; p=0.04]. CONCLUSIONS PSC-IPAA suffer more acute pouchitis and have worse functional outcomes than UC-IPAA. LdPSC-IPAA also have poorer quality of life.


Colorectal Disease | 2017

A collaborative review of the current concepts and challenges of anastomotic leaks in colorectal surgery.

A. Vallance; S. D. Wexner; Mariana Berho; Ronan A. Cahill; Mark G. Coleman; N. Haboubi; R. J. Heald; Robin H. Kennedy; B. Moran; Neil Mortensen; R. W. Motson; R. Novell; P. R. O'Connell; Frédéric Ris; T. A. Rockall; A. Senapati; A. Windsor; David Jayne

The reduction of the incidence, detection and treatment of anastomotic leakage (AL) continues to challenge the colorectal surgical community. AL is not consistently defined and reported in clinical studies, its occurrence is variably reported and its impact on longterm morbidity and health‐care resources has received relatively little attention. Controversy continues regarding the best strategies to reduce the risk. Diagnostic tests lack sensitivity and specificity, resulting in delayed diagnosis and increased morbidity. Intra‐operative fluorescence angiography has recently been introduced as a means of real‐time assessment of anastomotic perfusion and preliminary evidence suggests that it may reduce the rate of AL. In addition, concepts are emerging about the role of the rectal mucosal microbiome in AL and the possible role of new prophylactic therapies. In January 2016 a meeting of expert colorectal surgeons and pathologists was held in London, UK, to identify the ongoing controversies surrounding AL in colorectal surgery. The outcome of the meeting is presented in the form of research challenges that need to be addressed.


World Journal of Gastrointestinal Surgery | 2015

Natural history of uncomplicated sigmoid diverticulitis

Nicolas Buchs; Neil Mortensen; Frédéric Ris; Philippe Morel; Pascal Gervaz

While diverticular disease is extremely common, the natural history (NH) of its most frequent presentation (i.e., sigmoid diverticulitis) is poorly investigated. Relevant information is mostly restricted to population-based or retrospective studies. This comprehensive review aimed to evaluate the NH of simple sigmoid diverticulitis. While there is a clear lack of uniformity in terminology, which results in difficulties interpreting and comparing findings between studies, this review demonstrates the benign nature of simple sigmoid diverticulitis. The overall recurrence rate is relatively low, ranging from 13% to 47%, depending on the definition used by the authors. Among different risk factors for recurrence, patients with C-reactive protein > 240 mg/L are three times more likely to recur. Other risk factors include: Young age, a history of several episodes of acute diverticulitis, medical vs surgical management, male patients, radiological signs of complicated first episode, higher comorbidity index, family history of diverticulitis, and length of involved colon > 5 cm. The risk of developing a complicated second episode (and its corollary to require an emergency operation) is less than 2%-5%. In fact, the old rationale for elective surgery as a preventive treatment, based mainly on concerns that recurrence would result in a progressively increased risk of sepsis or the need for a colostomy, is not upheld by the current evidence.


Gut | 2017

Acute lower GI bleeding in the UK: patient characteristics, interventions and outcomes in the first nationwide audit

Kathryn Oakland; Richard H. Guy; Raman Uberoi; Rachel Hogg; Neil Mortensen; Michael F. Murphy; Vipul Jairath

Objective Lower GI bleeding (LGIB) is a common reason for emergency hospital admission, although there is paucity of data on presentations, interventions and outcomes. In this nationwide UK audit, we describe patient characteristics, interventions including endoscopy, radiology and surgery as well as clinical outcomes. Design Multicentre audit of adults presenting with LGIB to UK hospitals over 2 months in 2015. Consecutive cases were prospectively enrolled by clinical teams and followed for 28 days. Results Data on 2528 cases of LGIB were provided by 143 hospitals. Most were elderly (median age 74 years) with major comorbidities, 29.4% taking antiplatelets and 15.9% anticoagulants. Shock was uncommon (58/2528, 2.3%), but 666 (26.3%) received a red cell transfusion. Flexible sigmoidoscopy was the most common investigation (21.5%) but only 2.1% received endoscopic haemostasis. Use of embolisation or surgery was rare, used in 19 (0.8%) and 6 (0.2%) cases, respectively. 48% patients underwent no inpatient investigations. The most common diagnoses were diverticular bleeding (26.4%) and benign anorectal conditions (16.7%). Median length of stay was 3 days, 13.6% patients rebled during admission and 4.4% were readmitted with bleeding within 28 days. In-hospital mortality was 85/2528 (3.4%) and was highest in established inpatients (17.8%, p<0.0001) and in patients experiencing rebleeding (7.1%, p<0.0001). Conclusions Patients with LGIB have a high burden of comorbidity and frequent antiplatelet or anticoagulant use. Red cell transfusion was common but most patients were not shocked and required no endoscopic, radiological or surgical treatment. Nearly half were not investigated. In-hospital mortality was related to comorbidity, not severe haemorrhage.


Colorectal Disease | 2015

Technique for a stapled anastomosis following transanal total mesorectal excision for rectal cancer

E. Bracey; J. Knol; Nicolas Buchs; Oliver M. Jones; C. Cunningham; Richard H. Guy; Neil Mortensen; Roel Hompes

Transanal total mesorectal excision (taTME) is an emerging and exciting new technique in rectal cancer surgery. As with all novel techniques, new challenges arise, requiring small modifications of the technique. Here we present a simple technique that we have devised to facilitate a stapled anastomosis using standard circular staplers following a taTME.


Colorectal Disease | 2015

Fluorescence angiography in laparoscopic low rectal and anorectal anastomoses with pinpoint perfusion imaging--a critical appraisal with specific focus on leak risk reduction.

D. R. C. James; Frédéric Ris; Trevor M. Yeung; Rebecca Kraus; Nicolas Buchs; Neil Mortensen; Roel Hompes

Anastomotic dehiscence is one of the most feared complications in colorectal surgery leading to significant morbidity and mortality. Progressively lower anastomoses are associated with a greater leak rate. One of the key factors is the perfusion of the bowel to be joined. Presently, surgeons rely on a variety subjective measures to determine anastomotic perfusion and mechanical integrity however these have shortcomings. The aim of this paper is to appraise the literature on the use of fluorescence angiography (FA) in laparoscopic rectal surgery.

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