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Dive into the research topics where Nicholas Rieger is active.

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Featured researches published by Nicholas Rieger.


Annals of Surgery | 2008

Short-term outcomes of the Australasian Randomized Clinical Study comparing laparoscopic and conventional open surgical treatments for colon cancer The ALCCaS Trial

Peter Hewett; Randall A. Allardyce; Philip F. Bagshaw; Chris Frampton; Francis A. Frizelle; Nicholas Rieger; J. Shona Smith; Michael J. Solomon; Jacqueline H. Stephens; Andrew R. L. Stevenson

Background:Laparoscopy has revolutionized many abdominal surgical procedures. Laparoscopic colectomy has become increasingly popular. The short- and long-term benefits and satisfactory surgical oncological treatment of colorectal cancer by laparoscopic-assisted resection remain topical. The long-term outcomes of all international randomized controlled trials are still awaited, and short-term outcomes are important in the interim. Methods:Between January 1998 and April 2005, a multicenter, prospective, randomized clinical trial in patients with colon cancer was conducted. Six hundred and one eligible patients were recruited by 33 surgeons from 31 Australian and New Zealand centers. Patients were allocated to colectomy by either laparoscopic-assisted surgery (n = 294) or open surgery (n = 298). Patient demographics and secondary end-points, such as operative and postoperative complications, length of hospital stay, and histopathological data, will be presented in this article. Analysis was by intention-to-treat. Survival will be reported only as the study matures. Results:Histopathological parameters were similar between the two groups, except in regard to distal resection margins. There was no statistically significant difference found in postoperative complications, reoperation rate, or perioperative mortality. Statistically significant differences in quicker return of gastrointestinal function and shorter hospital stay were identified in favor of laparoscopic-assisted resection. A statistically significant increased rate of infective complications was seen in cases converted from laparoscopic-assisted to open procedures but with no difference in reoperation or in-hospital mortality. Conclusions:Laparoscopic-assisted colonic resection gives significant improvements in return of gastrointestinal function and length of stay, with an increased operative time and no difference in the postoperative complication rate.


Clinical Cancer Research | 2006

Identification of Early-Stage Colorectal Cancer Patients at Risk of Relapse Post-Resection by Immunobead Reverse Transcription-PCR Analysis of Peritoneal Lavage Fluid for Malignant Cells

Julia M. Lloyd; Cassandra M. McIver; Sally-Anne Stephenson; Peter Hewett; Nicholas Rieger; Jennifer E. Hardingham

Purpose: Colorectal cancer patients diagnosed with stage I or II disease are not routinely offered adjuvant chemotherapy following resection of the primary tumor. However, up to 10% of stage I and 30% of stage II patients relapse within 5 years of surgery from recurrent or metastatic disease. The aim of this study was to determine if tumor-associated markers could detect disseminated malignant cells and so identify a subgroup of patients with early-stage colorectal cancer that were at risk of relapse. Experimental Design: We recruited consecutive patients undergoing curative resection for early-stage colorectal cancer. Immunobead reverse transcription-PCR of five tumor-associated markers (carcinoembryonic antigen, laminin γ2, ephrin B4, matrilysin, and cytokeratin 20) was used to detect the presence of colon tumor cells in peripheral blood and within the peritoneal cavity of colon cancer patients perioperatively. Clinicopathologic variables were tested for their effect on survival outcomes in univariate analyses using the Kaplan-Meier method. A multivariate Cox proportional hazards regression analysis was done to determine whether detection of tumor cells was an independent prognostic marker for disease relapse. Results: Overall, 41 of 125 (32.8%) early-stage patients were positive for disseminated tumor cells. Patients who were marker positive for disseminated cells in post-resection lavage samples showed a significantly poorer prognosis (hazard ratio, 6.2; 95% confidence interval, 1.9-19.6; P = 0.002), and this was independent of other risk factors. Conclusion: The markers used in this study identified a subgroup of early-stage patients at increased risk of relapse post-resection for primary colorectal cancer. This method may be considered as a new diagnostic tool to improve the staging and management of colorectal cancer.


Annals of Surgery | 2012

Long-term outcomes of the Australasian randomized clinical trial comparing laparoscopic and conventional open surgical treatments for colon cancer: The Australasian Laparoscopic Colon Cancer Study Trial

Philip F. Bagshaw; Randall A. Allardyce; Chris Frampton; Frank A. Frizelle; Peter Hewett; Paul McMurrick; Nicholas Rieger; Jason Smith; Michael J. Solomon; Andrew R. L. Stevenson

Objective:We report a multicentered randomized controlled trial across Australia and New Zealand comparing laparoscopic-assisted colon resection (LCR) with open colon resection (OCR) for colon cancer. Background:Colon cancer is a significant worldwide health issue. This trial investigated whether the short-term benefits associated with LCR for colon cancer could be achieved safely, without survival disadvantages, in our region. Methods:A total of 601 patients with potentially curable colon cancer were randomized to receive LCR or OCR. Primary endpoints were 5-year overall survival, recurrence-free survival, and freedom from recurrence rates, compared using an intention-to-treat analysis. Results:On April 5, 2010, 587 eligible patients were followed for a median of 5.2 years (range, 1 week–11.4 years) with 5-year confirmed follow-up data for survival and recurrence on 567 (96.6%). Significant differences between the 2 trial groups were as follows: LCR patients were older at randomization, and their pathology specimens showed smaller distal resection margins; OCR patients had some worse pathology parameters, but there were no differences in disease stages. There were no significant differences between the LCR and OCR groups in 5-year follow-up of overall survival (77.7% vs 76.0%, P = 0.64), recurrence-free survival (72.7% vs 71.2%, P = 0.70), or freedom from recurrence (86.2% vs 85.6%, P = 0.85). Conclusions:In spite of some differences in short-term surrogate oncological markers, LCR was not inferior to OCR in direct measures of survival and disease recurrence. These findings emphasize the importance of long-term data in formulating evidence-based practice guidelines.


Diseases of The Colon & Rectum | 1997

Prospective trial of pelvic floor retraining in patients with fecal incontinence

Nicholas Rieger; David Wattchow; R. G. Sarre; S. J. Cooper; Caroline A. Rich; Gino T. P. Saccone; Ann C. Schloithe; James Toouli; John L. McCall

PURPOSE: Our aim was to prospectively evaluate pelvic floor retraining (PFR) in improving symptomatic fecal incontinence. METHODS: PFR was used to treat 30 patients with fecal incontinence (28 women; age range, 29–85 (median, 68) years). PFR was performed by a physiotherapist in the outpatient department according to a strict protocol and included biofeedback using an anal plug electromyometer. Manometry (24 patients), pudendal nerve terminal motor latency (PNTML, 16 patients), and anal ultrasound (14 patients) were done before commencing therapy. Independent assessment of symptoms was done at the commencement of therapy, at 6 weeks, and at 6 and 12 months posttherapy. RESULTS: Twenty patients (67 percent) had improved incontinence scores, with eight patients (27 percent) being completely or nearly free of symptoms. Of 28 patients followed up longer than six months, 14 achieved a 25 percent or greater improvement at six weeks, which was sustained in all cases. Fourteen had an initial improvement of less than 25 percent, with only four (29 percent) showing later improvement (P<0.0001). There was no relationship between results of the therapy and patient age, initial severity of symptoms, etiology of incontinence, and results of anal manometry, PNTML, and anal ultrasound. CONCLUSIONS: PFR is a physical therapy that should be considered as the initial treatment in patients with fecal incontinence. An improvement can be expected in up to 67 percent of patients. Initial good results can predict overall outcome.


Colorectal Disease | 2004

Parastomal hernia repair

Nicholas Rieger; James Moore; Peter Hewett; S. Lee; Jacqueline H. Stephens

Objective  The aim of this study was to audit the results of parastomal hernia repair.


Diseases of The Colon & Rectum | 2004

Open vs. Closed Lateral Internal Sphincterotomy for Idiopathic Fissure-in-Ano: A Prospective, Randomized, Controlled Trial

M. Wiley; P. Day; Nicholas Rieger; Jacqueline H. Stephens; James Moore

PURPOSE:Internal sphincterotomy remains the “gold standard” for treatment of anal fissure but is associated with a risk of imperfect continence. Recent studies have suggested that surgical technique (open vs. closed) may influence incontinence rates after sphincterotomy. This study was designed to assess the short-term and long-term incidence of incontinence after open and closed internal sphincterotomy.METHODS:Seventy-nine patients were randomly assigned to open or closed internal sphincterotomy, performed in standardized fashion by trainee staff. Standardized questionnaires assessing continence (modified Wexner score) were administered preoperatively and at 1, 6, and 52 weeks. Postoperative stay, pain scores, complications, and fissure healing were prospectively assessed by an independent observer.RESULTS:Three patients were lost to follow-up, leaving 36 closed (16 males; mean age, 45.1 years) and 40 open (21 males; mean age, 47.9 years) internal sphincterotomy patients for assessment. All operations were performed as day case procedures with no readmissions. At six weeks postoperative, 96 percent of fissures had healed. There were no significant differences in pain scores between closed and open internal sphincterotomy at Day 1 or Day 3 postoperative. New incontinence of any grade was seen in 6.8 percent of patients at 52-week follow-up. Three patients (4.1 percent, 1 closed, 2 open) suffered major incontinence at 52 weeks. There were no significant differences in continence at 1, 6, or 52 weeks, although more open patients experienced minor imperfections at 1 week.CONCLUSIONS:Incontinence after internal sphincterotomy is not insignificant. The technique (closed vs. open) does not seem to influence incontinence rates.


Diseases of The Colon & Rectum | 2003

Endosonographic imaging of anal sphincter injury: does the size of the tear correlate with the degree of dysfunction?

Frank Voyvodic; Nicholas Rieger; Sarah Skinner; Ann C. Schloithe; Gino T. P. Saccone; Michael R. Sage; David Wattchow

AbstractPURPOSE: This study was designed to test the hypothesis that the extent of anal sphincter muscle injury as graded at endosonography correlates with the degree of functional impairment. METHODS: Three hundred and thirty adults presenting for evaluation of fecal incontinence were recruited. Ultrasound was performed with a 7.5-MHz radial rotating axial endoprobe in the left lateral position. Anal sphincter muscle tears were graded on the basis of the degree of circumferential involvement (< or >25 percent) and by an assessment of the superoinferior longitudinal extent of an external anal sphincter tear. Muscles that demonstrated multiple tears, poor visualization, or fragmentation were classed as fragmented. Sphincter injuries were correlated with basal and squeeze pressures at manometry, pudendal nerve terminal latencies, and the severity of symptoms using the Parks-Browning clinical score. RESULTS: Patients with an intact external anal sphincter had a higher squeeze pressure (mean, 162.6 cm H2O) than those with a partial- (mean, 125.7 cm H2O) or full-length tear (mean, 124.9 cm H2O; P < 0.0001). There was no significant difference in squeeze pressure between those with partial- vs. full-length external anal sphincter tears nor between circumference tears < or >25 percent. Basal pressure was significantly lower in those with a full-length external anal sphincter tear (47.8 cm H2O) vs. an intact external anal sphincter (65.7 cm H2O; P < 0.001). The basal pressure in those with an intact internal anal sphincter was not significantly different from those with clearly defined internal anal sphincter tears, and the degree of circumferential involvement was also not important in this regard. However, those with a fragmented internal anal sphincter had a significantly lower basal pressure than other subgroups of internal anal sphincter injuries (P < 0.001). There was no association between external or internal anal sphincter status and the mean pudendal nerve terminal motor latency, suggesting the patient groups were neurologically similar. There was no significant association between external or internal anal sphincter status and the severity of reported symptoms. CONCLUSION: Correlations between the presence or absence of muscle tears and reduced manometric function have been identified. Further grading of tears was of less importance. No relationship between muscle injuries and the severity of clinical symptoms could be elicited.


Diseases of The Colon & Rectum | 1996

Investigation of fecal incontinence with endoanal ultrasound

Nicholas Rieger; James L. Sweeney; D. C. Hoffmann; J. F. Young; A. Hunter

PURPOSE: This study was undertaken to audit the results of endoanal ultrasound in patients with fecal incontinence. METHODS: Endoanal ultrasound was used to investigate 53 patients with fecal incontinence. Data for endoanal ultrasound were collected prospectively. Results were compared with clinical and obstetric history, obtained retrospectively from case notes, and were compared with manometric and operative findings. RESULTS: Sphincter abnormalities were identified in 42 of 53 patients. A total of 28 anterior defects were thought to be obstetric in origin. Fourteen other defects were secondary to anal pathology or surgery. Patients with anterior external sphincter defects either had complete defects (4 patients; mean age, 31 years) or proximal defects (24 patients; mean age, 55 years). For patients with a proximal defect, 38 percent gave a history of obstetric tear, episiotomy, or forceps delivery, and the rest declared having had an apparently normal delivery. Only 50 percent had a sphincter weakness that was evident on clinical examination. Of those studied with manometry, only 21 percent had low squeeze pressures consistent with an external sphincter defect. CONCLUSIONS: Sphincter defects seen on ultrasound may not have a history of obstetric trauma or abnormal clinical and manometric findings. Endoanal ultrasound is recommended in all patients with fecal incontinence to detect occult sphincter defects.


Anz Journal of Surgery | 2005

Randomized prospective controlled trial of lateral internal sphincterotomy versus injection of botulinum toxin for the treatment of idiopathic fissure in ano

Harish Iswariah; Jacqueline H. Stephens; Nicholas Rieger; David Rodda; Peter Hewett

Background:  Chronic anal fissure is a significant cause of morbidity. Internal sphincterotomy has long been the operative treatment of choice. Concerns remain, however, on its effects on continence. Botulinum toxin has been used as an agent for chemical sphincterotomy, causing temporary alleviation of sphincter spasm and allowing the fissure to heal. The aim of the present study was to compare the results of sphincterotomy to botulinum toxin.


British Journal of Surgery | 2009

Australasian Laparoscopic Colon Cancer Study shows that elderly patients may benefit from lower postoperative complication rates following laparoscopic versus open resection

R. Allardyce; P.F. Bagshaw; Chris Frampton; Frank A. Frizelle; Peter Hewett; Nicholas Rieger; J. S. Smith; Michael J. Solomon; Andrew R. L. Stevenson

A retrospective analysis of age‐related postoperative morbidity in the Australia and New Zealand prospective randomized controlled trial comparing laparoscopic and open resection for right‐ and left‐sided colonic cancer is presented.

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Andrew R. L. Stevenson

Royal Brisbane and Women's Hospital

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Michael J. Solomon

Royal Prince Alfred Hospital

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K. Pittman

University of Adelaide

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