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Dive into the research topics where Gregory L. Falk is active.

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Featured researches published by Gregory L. Falk.


Surgical Endoscopy and Other Interventional Techniques | 2005

Does routine intraoperative cholangiography prevent bile duct transection

E. Debru; Andrew H. Dawson; S. Leibman; M. Richardson; L. Glen; J. Hollinshead; Gregory L. Falk

BackgroundThe role of routine intraoperative cholangiography is controversial. The aim of this study was to assess the impact of routine intraoperative cholangiography on the incidence of common bile duct injuries, and to evaluate the operative outcome of laparoscopic cholecystectomy carried out in a major teaching hospital and review the literature.MethodsProspectively collected data on 3,145 laparoscopic cholecystectomies performed mainly by surgical trainees in the period 1990 to 2002 using routine intraoperative cholangiography with fluoroscopy were reviewed.ResultsThe mean age of the study sample (65.6% male, 34.4% female) was 54 years, and 16.9% of the patients had clinical acute cholecystitis. The conversion rate to open cholecystectomy was 4.3%. Intraoperative cholangiography was attempted for 90.7% of the patients with a 95.9% success rate. Five patients (0.16%) had common bile duct injuries. Four injuries had occurred in the first 5 years. One injury (0.06%) had occurred after 1995. This injury was identified intraoperatively and repaired laparoscopically. Routine intraoperative cholangiography prevented one definite common bile duct transection.ConclusionsIn this series using routine intraoperative cholangiography, there was a low rate and severity of common bile duct injuries, with a high intraoperative recognition rate. There was no bile duct transection or major injury requiring common bile duct reconstruction. Although intraoperative cholangiography helped in the immediate identification of injuries and the institution of appropriate therapy, injury was not completely prevented.


Journal of the American College of Cardiology | 2011

Left Atrial Compression and the Mechanism of Exercise Impairment in Patients With a Large Hiatal Hernia

Christopher Naoum; Gregory L. Falk; A. Ng; Tony Lu; Lloyd J Ridley; Alvin Ing; Leonard Kritharides; John Yiannikas

OBJECTIVES The purpose of this study was to determine the association between cardiac compression and exercise impairment in patients with a large hiatal hernia (HH). BACKGROUND Dyspnea and exercise impairment are common symptoms of a large HH with unknown pathophysiology. Studies evaluating the contribution of cardiac compression to the pathogenesis of these symptoms have not been performed. METHODS We collected clinical data from a consecutive series of 30 patients prospectively evaluated with resting and stress echocardiography, cardiac computed tomography, and respiratory function testing before and after laparoscopic HH repair. Left atrial (LA), inferior pulmonary vein, and coronary sinus compression was analyzed in relation to exercise capacity (metabolic equivalents [METs] achieved on Bruce treadmill protocol). RESULTS Exertional dyspnea was present in 25 of 30 patients (83%) despite normal mean baseline respiratory function. Moderate to severe LA compression was qualitatively present in 23 of 30 patients (77%) on computed tomography. Right and left inferior pulmonary vein and coronary sinus compression was present in 11 of 30 (37%), 12 of 30 (40%), and 26 of 30 (87%) patients, respectively. Post-operatively, New York Heart Association functional class and exercise capacity improved significantly (number of patients in New York Heart Association functional classes I, II, III, and IV: 6, 11, 11, and 2 vs. 26, 4, 0, and 0, respectively, p < 0.001; METs [percentage predicted]: 75 ± 24% vs. 112 ± 23%, p < 0.001) and resolution of cardiac compression was observed. Absolute change in LA diameter on the echocardiogram was the only independent cardiorespiratory predictor of exercise capacity improvement post-operatively (p = 0.006). CONCLUSIONS We demonstrate, for the first time, marked exercise impairment and cardiac compression in patients with a large HH and normal respiratory function. After HH repair, exercise capacity improves significantly and correlates with resolution of LA compression.


Journal of Thoracic Oncology | 2010

Ratio of Metastatic Lymph Nodes to Total Number of Nodes Resected is Prognostic for Survival in Esophageal Carcinoma

Clive J. Kelty; Catherine Kennedy; Gregory L. Falk

Introduction: The role of the number of metastatic nodes in esophageal cancer surgery is of interest. We assess predictors of survival after oesophagectomy for esophageal and gastroesophageal junction malignancy. Methods: Prospective data of consecutive patients undergoing oesophagectomy and systematic lymphadenectomy between 1991 and 2007. Results: Of 224 patients, 148 patients (66%) had adenocarcinoma, 70 (31%) squamous cell carcinoma, and 6 (2.6%) were other tumor types. Five-year survival was 43% with hospital mortality of 3.5%. Locoregional recurrence occurred in 14%. The total number of affected nodes significantly reduced survival (four or more metastatic nodes). Further analysis of the ratio of nodes affected to the total number resected showed a significant decrease in survival as the percentage of positive nodes increased (p < 0.001). Conclusions: Patients undergoing surgery for esophageal cancer should be staged according to a minimum total number of metastatic lymph nodes and ratios because this more accurately predicts survival than current staging systems.


Surgical Endoscopy and Other Interventional Techniques | 1999

In vitro assessment of back pressure on ventriculoperitoneal shunt valves. Is laparoscopy safe

M. L. Neale; Gregory L. Falk

AbstractBackground: Whereas there are case reports of laparoscopy in patients with ventriculoperitoneal shunts, there are no studies assessing the potential failure of shunt valves with the increased intra-abdominal pressure of laparoscopy. This study aims to assess this factor. Methods: An in vitro model was used to assess the potential for retrograde failure of ventriculoperitoneal shunt valves in a commonly used shunt. Nine shunts were subjected to graded increases in back pressure and observed for retrograde valve leak. Results: None of the shunts tested showed any signs of leak associated with the increased back pressure. However, disruption of shunt seals was noted in seven of the nine shunts, occurring at the minimal pressure of 80 mmHg. Conclusions: There appears to be minimal risk of retrograde failure of the valve system in the ventriculoperitoneal shunt tested. However, tests on different types of ventriculoperitoneal shunts would be needed to confirm these results if laparoscopy is to be considered safe in patients with ventriculoperitoneal shunts in situ.


Surgical Endoscopy and Other Interventional Techniques | 1998

Laparoscopically assisted massive splenectomy. A preliminary report of the technique of early hilar devascularization.

I. A. Nicholson; Gregory L. Falk; S. C. Mulligan

Abstract. Laparoscopic splenectomy has been safely performed for small spleens, but technical limitations have prevented massive splenectomy. We describe a technique of early hilar devascularization to enable massive splenectomy in three patients over the age of 80 years. Massive splenectomy was performed with minimal blood loss and minor morbidity. Early laparoscopic control of the splenic artery and vein will enable the safe removal of the massive spleen, without major laparotomy. Morbidity of splenectomy may be reduced by laparoscopy.


Surgical Endoscopy and Other Interventional Techniques | 2002

Laparoscopic excision of a Brunner’s gland hamartoma of the duodenum

H. G. Baladas; Thomas J. Borody; G. S. Smith; M. B. Dempsey; M. A. Richardson; Gregory L. Falk

Brunner’s gland hamartoma (adenoma) was first described in 1876. It is a rare hamartomatous lesion, with only ~100 cases reported in the world literature. Treatment has been by endoscopic snaring. Open surgical excision was reserved for cases where snaring had failed. We report a case of a Brunner’s gland hamartoma (2.4 cm) that was successfully resected by laparoscopic techniques. Postoperative hospital stay was brief (2 days), and there were no complications. This is the second reported case to be resected laparoscopically.


Journal of Laparoendoscopic & Advanced Surgical Techniques | 2010

Laparoscopic Duodenojejunostomy for the Treatment of Superior Mesenteric Artery (SMA) Syndrome: Case Series

Rebecca Wyten; Clive J. Kelty; Gregory L. Falk

Superior mesenteric artery (SMA) syndrome is an atypical, rare cause of both acute and chronic high intestinal obstruction. Identification of this syndrome can be a diagnostic dilemma and is frequently made by exclusion. The most characteristic symptoms are postprandial epigastric pain, eructation, fullness, and voluminous vomiting. Symptoms are caused by compression of the third portion of the duodenum against the posterior structures by a narrow-angled SMA. When nonsurgical management is not possible or the problem is refractory, surgical intervention is necessary. In this article, we report a case series of SMA syndrome in 3 patients with radiologic evaluation confirming compression of the third portion of the duodenum by the SMA with resultant proximal dilatation. The patients all successfully underwent laparoscopic duodenojejunal anastomosis.


Annals of The Royal College of Surgeons of England | 2015

Durability of giant hiatus hernia repair in 455 patients over 20 years

Pa Le Page; Ruelan Furtado; M Hayward; S Law; A Tan; Vivian Sj; H. Van der Wall; Gregory L. Falk

INTRODUCTION The surgical management of symptomatic giant hiatus hernia (GHH) aims to improve quality of life (QoL) and reduce the risk of life threatening complications. Previous reports are predominantly those with small sample sizes and short follow-up periods. The present study sought to assess a large cohort of patients for recurrence and QoL over a longer time period. METHODS This was a follow-up study of a prospectively collected database of 455 consecutive patients. Primary repair of GHH was evaluated by endoscopy/barium meal for recurrence and a standardised symptom questionnaire for QoL. Recurrence was assessed for size, elapsed time, oesophagitis and symptoms. RESULTS Objective and subjective review was achieved in 91.9% and 68.6% of patients. The median age was 69 years (range: 15-93 years) and 64% were female. Laparoscopic repair was completed in 95% (mesh in 6% and Collis gastroplasty in 7%). The 30-day mortality rate was 0.9%. The proportion of patients alive at five and ten years were 90% and 75% respectively. Postoperative QoL scores improved from a mean of 95 to 111 (p<0.01) and were stable over time (112 at 10 years). The overall recurrence rate was 35.6% (149/418) at 42 months; this was 11.5% (48/418) for hernias >2cm and 24.2% (101/418) for <2cm. The rate of new recurrence at 0-1 years was 13.7% (>2cm = 3.4%, <2cm = 10.3%), at 1-5 years it was 30.8% (>2cm = 9.5%, <2cm = 21.3%), at 5-10 years it was 40.1% (>2cm = 13.8%, <2cm = 26.3%) and at over 10 years it was 50.0% (>2cm = 25.0%, <2cm = 25.0%). Recurrence was associated with oesophagitis but not decreased QoL. Revision surgery was required in 4.8% of cases (14.8% with recurrence). There were no interval major GHH complications. CONCLUSIONS Surgery has provided sustained QoL improvements irrespective of recurrence. Recurrence occurred progressively over ten years and may predispose to oesophagitis.


Hpb Surgery | 1998

Lymphoepithelial Cyst of the Pancreas" Serum Markers do not Help

S. P. Chan; C. W. Hatton; Gregory L. Falk

We report a case of lymphoepithelial cyst of the pancreas with non-specific elevation of CA 19.9 and CEA. Pre-operative diagnosis by conventional means proved elusive, and only surgical resection and histopathology revealed the diagnosis. The origin and diagnosis are discussed by literature review.


Diseases of The Esophagus | 2008

Does systematic 2-field lymphadenectomy for esophageal malignancy offer a survival advantage? Results from 178 consecutive patients

David Martin; N. G. Church; Catherine Kennedy; Gregory L. Falk

More extensive resection for esophageal cancer has been reported to improve survival in several series. We compared results from an unselected consecutive cohort of patients undergoing radical esophagectomy, including removal of all periesophageal tissue with a 2-field abdominal and mediastinal lymphadenectomy for esophageal and gastroesophageal malignancy. A prospective electronic database was reviewed for patients with esophageal malignancy undergoing an open esophagectomy between 1991 and 2004. Data were analyzed on an SPSS file (version 12.0, Chicago, IL, USA) using chi(2) or Fishers exact test; odds ratio and 95% confidence interval; and the Kaplan-Meier method, log-rank test and Coxs proportional hazards regression for survival analysis. There were 178 patients with a median age of 65 years and a 70/30 male to female ratio. Median follow-up was 20.4 months. Pathology comprised adenocarcinoma in 64% of patients, squamous cell carcinoma 30%, and other malignancies 6%. Seventeen patients had neoadjuvant therapy. Hospital mortality was 3.3%. Complete resection was achieved in 87%. Local recurrence occurred at a median of 13 months in 6.7% of patients. Overall 5-year survival was 42%. For patients with invasive squamous cell carcinoma and adenocarcinoma the 5-year survival was 47% and 40.3%, respectively, and for patients without nodal involvement it was 71.5%, with one to four nodes involved, 23.5% and with >4 nodes, 5% (P < 0.001). Survival decreased with increasing direct tumor spread (P < 0.001) and pathological stage (P < 0.001). Esophageal resection with systematic 2-field lymphadenectomy can be performed with acceptable operative mortality and favorable survival.

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Christopher Naoum

University of British Columbia

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Ruelan Furtado

Concord Repatriation General Hospital

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Clive J. Kelty

Concord Repatriation General Hospital

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Oleksandr Khoma

Concord Repatriation General Hospital

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