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Dive into the research topics where J. Evans is active.

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Featured researches published by J. Evans.


Digestive Surgery | 2003

Minimally Invasive Retroperitoneal Pancreatic Necrosectomy

Saxon Connor; Paula Ghaneh; Michael Raraty; Robert Sutton; E. Rosso; C. Garvey; M. Hughes; J. Evans; Peter Rowlands; John P. Neoptolemos

Introduction: Open surgery for pancreatic necrosis is associated with considerable morbidity and mortality. We report the results of a recently developed minimally invasive technique that we adopted in 1998. Methods: A descriptive explanation of the approach is given together with the results of a retrospective analysis of patients who underwent a minimally invasive retroperitoneal pancreatic necrosectomy (MIRP) between August 1998 and April 2002. Patients: There were 24 patients with a median (range) age of 61 (29–75) years. The initial median (range) APACHE II score was 8 (2–21). All patients had infected pancreatic necrosis with at least 50% pancreatic necrosis. In three patients it was not possible to complete the first MIRP because of technical reasons. Results: A total of 88 procedures were performed with a median (range) of 4 (0–8) per patient. Twenty-one (88%) patients developed 36 complications during the course of their illness. Five patients required an additional open procedure: 2 for subsequent distant collections, 2 for bleeding and 1 for persisting sepsis and a distant abscess. Six (25%) patients who had MIRP died. The median (range) post-operative hospital stay was 51 (5–200) days. Conclusions: MIRP is a new technique that has shown promising results, and could be preferable to open pancreatic necrosectomy in selected patients. However, unresolved issues remain to be overcome and the exact role of MIRP in the management of pancreatic necrosis has yet to be defined.


Digestive Surgery | 2003

Pancreatic Pseudocyst in Chronic Pancreatitis: Endoscopic and Surgical Treatment

Edoardo Rosso; Nicholas Alexakis; Paula Ghaneh; Martin Lombard; Howard Smart; J. Evans; John P. Neoptolemos

SurgeryIntroductionThe incidence and prevalence of chronic pancreatitisappear to be increasing [1–4]. Pancreatic pseudocyst is acommon complication of chronic as well as acute pancre-atitis that is unrelated to the underlying aetiology. Ad-vances in radiological techniques have in part led to anincrease in the diagnosis of pseudocyst and better charac-terization of associated complications. There is now a bet-ter understanding of the natural history of pseudocysts inrelation to the underlying disease. The introduction ofnew treatment modalities has also increased the optionsfor surgical management. Thus with better knowledge ofthe disease and with technical advances the indications,timing and methods to treat pancreatic pseudocysts haveundergone a marked evolutionary change.DefinitionA pancreatic pseudocyst is a localised collection ofpancreatic-enzyme-rich fluid, originating in or adjacent tothe pancreas and enclosed in a wall of granulation and/orfibrous tissue lacking an epithelial lining [5]. The princi-ple mechanism leading to pseudocyst formation is be-lieved to involve disruption of the main pancreatic ductand/or peripheral ductules causing leakage and activationof pancreatic enzymes, which in turn leads to localisedautodigestion and necrosis of pancreatic parenchyma.This evokes an inflammatory response with the formationof a distinct pseudocyst wall composed of granulation tis-sue and blood vessels that organizes with more connectivetissue and fibrosis [6–11].On-table pancreatography [12] and endoscopic retro-grade cholangiopancreatography (ERCP) have demon-strated a communication between the pseudocyst and thepancreatic ductal system in up to 80% of the patients [13,14], and peripheral or main pancreatic duct disruption isknown to be an early event in acute pancreatitis [15].Rarely disruption of a retention cyst [16] or trauma thatdisrupts the pancreatic ductal system may also lead to apseudocyst [17–19].


Scandinavian Journal of Surgery | 2005

Surgery in the Treatment of Acute Pancreatitis Minimal Access Pancreatic Necrosectomy

Saxon Connor; Michael Raraty; Nathan Howes; J. Evans; Paula Ghaneh; Robert Sutton; John P. Neoptolemos

Between 5% and 10% of patients with acute pancreatitis will develop infected pancreatic necrosis. Traditional open surgery for this condition carries a mortality rate of up to 50%, and therefore a number of less invasive techniques have been developed, including radiological drainage and a minimal access retroperitoneal approach. No randomised controlled trials have been published which compare these techniques. Indications for minimal access surgery are the same as for open surgery, i.e. infected pancreatic necrosis or failure to improve with extensive sterile necrosis. Access is obtained to the pancreatic necrosis via the left loin and necrosectomy performed using an operating nephroscope, and this often requires several procedures to remove all necrotic tissue. The cavity is continuously irrigated on the ward in between procedures. The results of this approach are encouraging, with less systemic upset to the patient, a lower incidence of post-operative organ failure when compared with open surgery, and a reduced requirement for ITU support. There is also a trend towards a lower mortality rate, although this does not reach statistical significance on the data published so far. Current evidence suggests that a minimal access approach to pancreatic necrosis is feasible, well tolerated and beneficial for the patient when compared with open surgery.


Pancreatology | 2004

Hereditary pancreatic endocrine tumours

N. Alexakis; Saxon Connor; Paula Ghaneh; Martin Lombard; Howard Smart; J. Evans; M. Hughes; C. Garvey; J Vora; Sobhan Vinjamuri; Robert Sutton; John P. Neoptolemos

The two main types of hereditary pancreatic neuroendocrine tumours are found in multiple endocrine neoplasia type 1 (MEN-1) and von Hippel-Lindau disease (VHL), but also in the rarer disorders of neurofibromatosis type 1 and tuberous sclerosis. This review considers the major advances that have been made in genetic diagnosis, tumour localization, medical and surgical treatment and palliation with systemic chemotherapy and radionuclides. With the exception of the insulinoma syndrome, all of the various hormone excess syndromes of MEN-1 can be treated medically. The role of surgery however remains controversial ranging from no intervention (except enucleation for insulinoma), intervening for tumours diagnosed only by biochemical criteria, intervening in those tumours only detected radiologically (1–2 cm in diameter) or intervening only if the tumour diameter is >3 cm in diameter. The extent of surgery is also controversial, although radical lymphadenectomy is generally recommended. Pancreatic tumours associated with VHL are usually non-functioning and tumours of at least 2 cm in diameter should be resected. Practice guidelines recommend that screening in patients with MEN-1 should commence at the age of 5 years for insulinoma and at the age of 20 years for other pancreatic neuroendocrine tumours and variously at 10–20 years of age for pancreatic tumours in patients with VHL. The evidence is increasing that the life span of patients may be significantly improved with surgical intervention, mandating the widespread use of tumour surveillance and multidisciplinary team management.


Digestive Surgery | 2005

Positron emission tomography does not add to computed tomography for the diagnosis and staging of pancreatic cancer.

D. Lytras; Saxon Connor; L. Bosonnet; R. Jayan; J. Evans; M. Hughes; C. Garvey; Paula Ghaneh; Robert Sutton; Sobhan Vinjamuri; John P. Neoptolemos

Background: Positron emission tomography (PET) has been proposed for pancreatic cancer diagnosis and staging. Methods: 112 patients with suspected pancreatic cancer underwent 18F-fluoro-2-deoxy-D-glucose gamma camera PET and computed tomography (CT), of whom 62 also had laparoscopic ultrasonography and 70 underwent abdominal exploration for potential resection. The final diagnosis was malignancy in 78 and benign disease in 34 patients (25 with chronic pancreatitis). Results: The diagnostic sensitivity and specificity for PET were 73 and 60% compared to 89 and 65% for CT respectively (Cohen’s ĸ = 0.59). In 30 patients CT was equivocal with cancer in 14 and benign disease in 16. PET correctly diagnosed 13 of these patients (cancer in 6 and benign disease in 7), interpreted 4 as equivocal (cancer in 3 and benign disease in 1) but was incorrect in the remaining 13 patients (cancer in 5 and benign disease in 8). The sensitivity and specificity for detecting small volume metastatic disease were 20 and 94% for CT and 22 and 91% for PET, respectively. Conclusion: PET had a similar accuracy to that of CT for imaging pancreatic cancer but it did not provide any additional information in patients with equivocal CT findings and currently would seem of little benefit for the staging of pancreatic cancer.


British Journal of Surgery | 2003

Increasing age and APACHE II scores are the main determinants of outcome from pancreatic necrosectomy

Saxon Connor; Paula Ghaneh; Michael Raraty; E. Rosso; Mark Hartley; C. Garvey; M. Hughes; Richard G. McWilliams; J. Evans; Peter Rowlands; Robert Sutton; John P. Neoptolemos

The aim of this study was to identify factors associated with death after surgery in patients with extensive pancreatic necrosis.


Surgery | 2008

The platelet-lymphocyte ratio improves the predictive value of serum CA19-9 levels in determining patient selection for staging laparoscopy in suspected periampullary cancer.

Richard A. Smith; L. Bosonnet; Paula Ghaneh; Robert Sutton; J. Evans; Priya Healey; Connall Garvey; M. Hughes; Michael Raraty; Fiona Campbell; John P. Neoptolemos

BACKGROUND The objective of this study was to identify whether the preoperative platelet-lymphocyte (P/L) ratio might improve the predictive value of CA19-9 levels in stratifying a patient group with suspected periampullary malignancy who do not require staging laparoscopy. METHODS Patients with suspected periampullary cancer were identified from a prospectively maintained 10-year database. Only patients with resectable disease who underwent staging laparoscopy and subsequent laparotomy were included. Low-risk groups were stratified using a CA19-9 cutoff value of < or = 150 kU/l (or < or = 300 kU/l in patients with a concurrent bilirubin concentration > 35 micromol/l) and a P/L ratio value of < or = 150. RESULTS From 263 patients, preoperative CA19-9 levels and P/L ratios were available in 216 and 225 patients, respectively. The positive and negative predictive values for resectability, sensitivity, and specificity for CA19-9 levels < or = 150 kU/l were 83%, 36%, 51%, and 73%, respectively. For P/L ratios < or = 150, these levels were 81%, 38%, 51%, and 72%, respectively. When combining the requirement for both CA19-9 levels and P/L ratios to be < or = 150 (n = 38 out of 183), both positive predictive value (95%) and specificity (96%) were improved (Fisher exact test, P =.065 and P < .001, respectively); 21% of laparoscopies were avoidable when using these criteria. Increasing T stage (P = .005), vascular invasion (P < .001), perineural invasion (P = .008), and resection margin involvement (P < .001) were all associated with greater preoperative P/L ratios in resected periampullary adenocarcinoma (n = 204). CONCLUSIONS The preoperative P/L ratio reflects an index of tumor invasiveness and merits prospective evaluation as an adjunct to CA19-9 in determining the requirement for laparoscopic staging in patients with potentially resectable periampullary malignancy.


Digestive Surgery | 2004

Fungal Infection but Not Type of Bacterial Infection Is Associated with a High Mortality in Primary and Secondary Infected Pancreatic Necrosis

Saxon Connor; Nicholas Alexakis; T. Neal; Michael Raraty; Paula Ghaneh; J. Evans; M. Hughes; Peter Rowlands; C. Garvey; Robert Sutton; John P. Neoptolemos

Introduction: Knowledge of microbiology in the prognosis of patients with necrotizing pancreatitis is incomplete. Aim: This study compared outcomes based on primary and secondary infection after surgery for pancreatic necrosis. Method: From a limited prospective database of pancreatic necrosectomy, a retrospective case note review was performed (October 1996 to April 2003). Results: 55 of 73 patients had infected pancreatic necrosis at the first necrosectomy. 25 of 47 patients had resistant bacteria to prophylactic antibiotics (n = 21) or did not receive prophylactic antibiotics (n = 4), but this was not associated with a higher mortality (9 of 25) compared to those with sensitive organisms (4 of 22). Patients with fungal infection (n = 6) had a higher initial median (95% CI) APACHE II score compared to those without (11 (9–13) verus 8.5 (7–10), p = 0.027). Five of six patients with fungal infection died compared to 13 of 47 who did not (p = 0.014). With the inclusion of secondary infections 21 (32%) of 66 patients had fungal infection with 10 (48%) deaths compared to 11 (24%) of 45 patients without fungal infection (p = 0.047). Conclusion: Whether associated with primary or secondary infected pancreatic necrosis, fungal but not bacterial infection was associated with a high mortality.


Pancreatology | 2007

When is pancreatitis considered to be of biliary origin and what are the implications for management

N. Alexakis; Martin Lombard; Michael Raraty; Paula Ghaneh; Howard Smart; Ian Gilmore; J. Evans; M. Hughes; C. Garvey; Robert Sutton; John P. Neoptolemos

Acute pancreatitis is a disease caused by gallstones in 40–60% of patients. Identification of these patients is extremely important, since there are specific therapeutic interventions by endoscopic sphincterotomy and/or cholecystectomy. The combination of trans-abdominal ultrasound (stones in the gallbladder and/or main bile duct) and elevated serum alanine transaminase (circa >60 IU/l within 48 h of presentation) indicates gallstones as the cause in the majority of patients with acute pancreatitis. In the presence of a severe attack this is a strong indication for intervention by endoscopic sphincterotomy. The presence of a significant main bile duct dilatation is also strongly indicative of gallstones and should prompt the use of endoluminal ultrasonography: >8 mm diameter with gallbladder in situ, or >10 mm following cholecystectomy if aged <70 years and >12 mm, respectively, if ≧70 years. In mild pancreatitis surgically fit patients should be treated by cholecystectomy, and intra-operative cholangiography, as pre-operative biliary imaging is not efficient in this setting. Patients who are not fit for cholecystectomy should undergo prophylactic endoscopic sphincterotomy to prevent further attacks. In the post-acute-phase, pancreatitis patients in whom the aetiology is uncertain should undergo endoluminal ultrasonography. Thisis the most sensitive method for the detection of cholelithiasis and choledocholithiasis and may reveal alternative aetiological factors such as a small ampullary or pancreatic cancer. A number of recent studies have shown that bile crystal analysis, a marker for microlithiasis, increases the yield of positive results over and above endoluminal ultrasonography, and should be considered as part of the modern investigative algorithm.


British Journal of Surgery | 2004

Major resection for chronic pancreatitis in patients with vascular involvement is associated with increased postoperative mortality.

N. Alexakis; Robert Sutton; Michael Raraty; Saxon Connor; Paula Ghaneh; M. Hughes; C. Garvey; J. Evans; John P. Neoptolemos

The aim was to evaluate the outcome of major resection for chronic pancreatitis in patients with and without vascular involvement.

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Paula Ghaneh

University of Liverpool

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Michael Raraty

Royal Liverpool University Hospital

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M. Hughes

Royal Liverpool University Hospital

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C. Garvey

Royal Liverpool University Hospital

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Howard Smart

Royal Liverpool University Hospital

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Martin Lombard

Royal Liverpool University Hospital

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N. Alexakis

Royal Liverpool University Hospital

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