R R Dozois

Mayo Clinic - Rochester, Rochester, Minnesota, United States

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Publications (193)890.91 Total impact

  • R.R. Dozois

    No preview · Article · Jul 2008 · Colorectal Disease
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    ABSTRACT: Ileal pouch-anal anastomosis (IPAA) is performed routinely for chronic ulcerative colitis. Using data from a prospective database and annual standardized questionnaires, functional outcome, complications and quality of life (QoL) after IPAA were assessed. Some 1885 IPAA operations were performed for chronic ulcerative colitis over a 20-year period (mean follow-up 11 years). The mean age at the time of IPAA was 34.1 years, increasing from 31.2 years (1981-1985) to 36.3 years (1996-2000). The overall rate of pouch success at 5, 10, 15 and 20 years was 96.3, 93.3, 92.4 and 92.1 per cent respectively. Mean daytime stool frequency increased from 5.7 at 1 year to 6.4 at 20 years (P < 0.001), and also increased at night (from 1.5 to 2.0; P < 0.001). The incidence of frequent daytime faecal incontinence increased from 5 to 11 per cent during the day (P < 0.001) and from 12 to 21 per cent at night (P < 0.001). QoL remained unchanged and 92 per cent remained in the same employment. Seventy-six patients were eventually diagnosed with indeterminate colitis and 47 with Crohn's disease. IPAA is a reliable surgical procedure for patients requiring proctocolectomy for chronic ulcerative colitis and indeterminate colitis. The clinical and functional outcomes are excellent and stable for 20 years after operation.
    No preview · Article · Mar 2007 · British Journal of Surgery
  • M Prudhomme · N Dehni · R R Dozois · E Tiret · R Parc
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    ABSTRACT: Pouch failure occurs in up to 10 per cent of patients after ileal pouch-anal anastomosis (IPAA). The aims of this study were to determine the reasons for pouch excision and to evaluate the outcome of the perineal wound after pouch excision. Between 1984 and 2002, 91 patients with severe ileal pouch dysfunction were treated. This was a retrospective analysis of data collected prospectively from 24 patients who underwent pouch excision. Patients were grouped according to the final histological diagnosis. Fourteen patients with Crohn's disease developed extensive fistulous disease and/or recurrent abscesses, of whom six had a persistent perineal sinus after pouch excision. Five patients had familial adenomatous polyposis, in three of whom desmoid tumours were the cause of failure. Three patients had chronic ulcerative colitis and developed recurrent pelvic sepsis. Finally, two patients with multiple colorectal adenocarcinoma developed recurrent cancer (one) or sepsis (one). Sepsis was the principal reason for pouch excision and was usually associated with recrudescent Crohn's disease in the pouch. Perineal wound healing was problematic after pouch excision for Crohn's disease.
    No preview · Article · Jan 2006 · British Journal of Surgery
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    ABSTRACT: Differences in conventional outcomes such as functional results and the rate of complications have caused a controversy about whether the ileal pouch anal anastomosis or the ileorectal anastomosis is the preferred surgical treatment for patients with familial adenomatous polyposis. We therefore sought to ascertain not only the surgical results but also the perceptions of patients about their outcomes. Between 1981 and 1998, 152 patients at our institution had an ileal pouch-anal anastomosis and 32 patients had an ileorectal anastomosis for familial adenomatous polyposis. Of these 184 patients, 173 were sent a study-specific quality-of-life questionnaire and the Short Form 36 health survey to determine their health-related quality of life. Ninety-four ileal pouch patients and 21 ileorectal patients returned the surveys. No difference was found in early postoperative complications, 5-year probability for complications, or functional results after either procedure. On the Short Form 36 health survey, the ileorectal patients had a lower mental health summary score compared with that of the ileal pouch patients but a similar physical health summary score. The study-specific questionnaire found both groups to have a comparable quality of life. Because ileal pouch-anal anastomosis has the advantage of removing as much at-risk tissue as possible with similar functional results and better mental health, it may be considered the preferred operation for most patients with familial adenomatous polyposis.
    No preview · Article · Dec 2005 · Diseases of the Colon & Rectum
  • N Dehni · G Remacle · R R Dozois · F Banchini · E Tiret · R Parc
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    ABSTRACT: Surgical revision may be possible in patients with a poor outcome following ileal pouch-anal anastomosis (IPAA), using either a transanal approach or a combined abdominoperineal approach with pouch revision and reanastomosis. Sixty-four patients underwent revisional surgery. The indication for salvage was sepsis in 47 patients, mechanical dysfunction in ten, isolated complications of the residual glandular epithelial cuff in three and previous intraoperative difficulties in four patients. A transanal approach was used in 19 patients and a combined abdominoperineal procedure in 45. Six of the latter had pouch enlargement and 25 received a new pouch. During a mean(s.d.) follow-up of 30(25) months, three patients required pouch excision because of Crohn's disease. Two patients had poor continence after abdominoperineal surgery. At last follow-up 60 (94 per cent) of 64 patients had a functional pouch. Half of the patients experienced some degree of daytime and night-time incontinence, but it was frequent in only 15 per cent. Of 58 patients analysed, 27 of 40 who had an abdominoperineal procedure and 13 of 18 who had transanal surgery rated their satisfaction with the outcome as good to excellent. Surgical revision after failure of IPAA was possible in most patients, yielding an acceptable level of bowel function in two-thirds of patients.
    No preview · Article · Jun 2005 · British Journal of Surgery
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    ABSTRACT: To evaluate in what manner ageing affects functional outcome and quality of life (QoL) in patients with chronic ulcerative colitis (CUC) after ileal pouch-anal anastomosis (IPAA). Short-term function and QoL after IPAA is good. However, patients are usually young, and little is known about the influence of time and ageing on long-term outcomes after IPAA. Using a standardized questionnaire, functional outcome, QoL, and complications were assessed prospectively in a cohort of 409 patients followed annually for 15 years after IPAA. Follow-up was complete in the single cohort of 409 patients and functional and QoL outcomes summarized at 5, 10, and 15 years. Daytime stool frequency changed little (mean 6), while nighttime frequency increased from 1 stool to 2 stools. Incontinence for gas and stool increased from 1% to 10% during the day and from 2% to 24% at night over 15 years. The cumulative probability of pouchitis increased from 28% at 5 years to 38% at 10 years and to 47% at 15 years. Bowel obstruction and stricture were other principal long-term complications. At 15 years, 91% of patients had kept the same job. Work was not affected by the surgery in 83%, while social activities, sports, traveling, and sexual life all improved after surgery and did not deteriorate over time. These long-term results in a single cohort of 409 IPAA patients are unique and are likely a more accurate reflection of long-term outcome than has been previously reported. These data support the conclusion that IPAA is a durable operation for patients requiring proctocolectomy for CUC; functional and QoL outcomes are good, predictable, and stable for 15 years after operation.
    Full-text · Article · Nov 2004 · Annals of Surgery
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    ABSTRACT: This study was designed to evaluate pregnancy, delivery, and functional outcome in females before and after ileal pouch-anal anastomosis for chronic ulcerative colitis. From a prospective database of 1,454 patients who underwent ileal pouch-anal anastomosis for chronic ulcerative colitis between 1981 and 1995, a standardized questionnaire was sent to all female patients aged 40 years or younger at the time of ileal pouch-anal anastomosis (n = 544). The response rate was 83 percent (450/544) with a mean follow-up after ileal pouch-anal anastomosis of 13 years. A total of 141 females were pregnant after the chronic ulcerative colitis diagnosis, but before ileal pouch-anal anastomosis (236 pregnancies; mean, 1.7) and 87 percent delivered vaginally. A mean of five (range, 1-16) years after ileal pouch-anal anastomosis, 135 females were pregnant (232 pregnancies; mean, 1.7). Comparison of pregnancy and delivery before and after ileal pouch-anal anastomosis in the same females (n = 37) showed no difference in birth weight, duration of labor, pregnancy/delivery complications, vaginal delivery rates (59 percent before vs. 54 percent after ileal pouch-anal anastomosis), and unplanned cesarean section (19 vs.14 percent). Planned cesareans occurred only after ileal pouch-anal anastomosis and were prompted by obstetrical concerns in only one of eight. Pouch function at first follow-up after delivery (mean, 7 months) was similar to pregravida function. After ileal pouch-anal anastomosis, daytime stool frequency was the same after delivery as pregravida (5.4 vs. 5.4, not significant) but was increased at the time of last follow-up (68 months after delivery; 5.4 vs. 6.4; P < 0.001). The rate of occasional fecal incontinence also was higher (20 percent after ileal pouch-anal anastomosis and 21 percent pregravida vs. 36 percent at last follow-up; P = 0.01). No difference in functional outcome was noted compared with females who were never pregnant after ileal pouch-anal anastomosis (n = 307). Age and becoming pregnant did not affect the probability of pouch-related complications, such as stricture, pouchitis, and obstruction. Successful pregnancy and vaginal delivery occur routinely in females with chronic ulcerative colitis before and after ileal pouch-anal anastomosis. The method of delivery should be dictated by obstetrical considerations. Pouch function and the incidence of complications in females with pregnancies seem largely unaffected long-term.
    No preview · Article · Jul 2004 · Diseases of the Colon & Rectum
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    ABSTRACT: Restorative proctocolectomy (RPC) eliminates the risk of colorectal adenocarcinoma in familial adenomatous polyposis (FAP) patients, but desmoid tumors, duodenal, and ileal adenomas can still develop. Our aim was to assess the long-term outcome of FAP patients after RPC. FAP patients who had RPC between 1983 and 1990 were contacted for interview and upper gastrointestinal (GI) and ileal pouch endoscopy. Sixty-two males and 48 females had undergone hand-sewn RPC during this period. One patient died postoperatively (0.9%). Among 96 patients available for a minimal follow-up of 11 years, 7 patients died: 3 from causes unrelated to FAP, 2 from metastatic colorectal cancer, and 2 from mesenteric desmoid tumor (MDT). Thirteen patients had a symptomatic MDT (13.5%). Of 73 patients who had an upper GI endoscopy, 52 developed duodenal and/or ampullary adenomas. Four patients required surgical treatment of their duodenal lesions. Among 54 patients who underwent ileal pouch endoscopy, pouch adenomas were noted in 29. No invasive duodenal or ileal pouch carcinoma were detected. Functional results of RPC were significantly worse in MDT patients. RPC eliminates the risk of colorectal cancer, and close upper GI surveillance may help prevent duodenal malignancy. MDTs are the principal cause of death, once colorectal cancer has been prevented, and the main reason for worsening functional results.
    Preview · Article · Apr 2004 · Annals of Surgery

  • No preview · Article · Jan 2004 · Transactions of the Meeting of the American Surgical Association

  • No preview · Article · Apr 2003 · Gastroenterology
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    ABSTRACT: This study was designed to define the different types of strictures, the factors favoring their occurrence, and their treatment after ileal pouch-anal anastomosis. Between January 1981 and June 1996, 1,884 ileal pouch-anal anastomoses were constructed at the Mayo Clinic in Rochester, Minnesota. Data were collected prospectively and included age, gender, type of underlying diseases (chronic ulcerative colitis familial adenomatous polyposis), proctologic antecedents, technique of anastomosis, intraoperative difficulties, and postsurgical complications. Strictures were categorized as nonfibrotic and fibrotic on the basis of the presence or absence of a fibrotic segment at the anal canal anastomosis that was responsible for pouch-outlet obstruction requiring at least one dilation. Strictures occurred in 213 patients (11.2 percent; 11 percent for chronic ulcerative colitis and 12 percent for familial adenomatous polyposis; P = not significant). Strictures were nonfibrotic in 86.4 percent of patients and fibrotic in 13.6 percent. A greater number of strictures were observed after a handsewn anastomosis (12 percent) than after a stapled anastomosis (4 percent; P = 0.03). Intraoperative technical difficulties were associated with 13 percent of all strictures regardless of the type of stricture (fibrotic, 7.5 percent; nonfibrotic, 14 percent; P = 0.4). Postoperative complications such as abscess, fistula, and pouch retraction were found in 13 percent of cases and were primarily associated with fibrotic strictures. Treatment included dilation, which was successful in 95 percent of nonfibrotic strictures but in only 45 percent of fibrotic strictures (P = 0.0001). Surgical treatment was required in 25 strictures (12 percent), including excision of the strictured segment with mucosal advancement flap (5 patients), excision of the pouch with permanent ileostomy (9 patients), or redo pouch (3 patients). With one exception, all excised pouches were associated with other perianastomotic complications, such as abscess, fistula, and pouch retraction. The remaining eight patients had other surgical procedures because of abscess (n = 3), division of an obstructive bridge (n = 2), and débridement and curettage of a fistula (n = 3) with dilation for associated strictures. Strictures were observed in 11.2 percent of the patients in this study. Nonfibrotic strictures responded well to anal dilation, whereas fibrotic strictures were more commonly associated with intraoperative or postoperative complications, often necessitated surgical therapy to salvage pouch function, and were eventually responsible for pouch failure in nine patients.
    No preview · Article · Feb 2003 · Diseases of the Colon & Rectum
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    ABSTRACT: Klippel-Trenaunay syndrome (KTS) is a congenital vascular anomaly characterized by limb hypertrophy, cutaneous hemangiomas, and varicosities. GI hemorrhage is a potentially serious complication secondary to diffuse hemangiomatous involvement of the gut. We report on three patients with KTS who presented with transfusion-dependent anemia and life-threatening bleeding due to extensive cavernous hemangiomas involving the rectum. Two patients were treated by proctocolectomy and coloanal anastomosis, which preserved anal function while controlling bleeding. The third patient required an abdominoperineal resection because of extensive rectal, perianal, and perineal angiomatosis. The literature on the evaluation and management of GI hemorrhage in KTS, particularly of colorectal origin, is reviewed.
    No preview · Article · Oct 2001 · The American Journal of Gastroenterology
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    ABSTRACT: Information in the literature regarding salvage treatment for patients with locally recurrent colorectal cancer who have previously been treated with high or moderate dose external beam irradiation (EBRT) is scarce. A retrospective review was therefore performed in our institution to determine disease control, survival, and tolerance in patients treated aggressively with surgical resection and intraoperative electron irradiation (IOERT) +/- additional EBRT and chemotherapy. From 1981 through 1994, 51 previously irradiated patients with recurrent locally advanced colorectal cancer without evidence of distant metastatic disease were treated at Mayo Clinic Rochester with surgical resection and IOERT +/- additional EBRT. An attempt was made to achieve a gross total resection before IOERT if it could be safely accomplished. The median IOERT dose was 20 Gy (range, 10--30 Gy). Thirty-seven patients received additional EBRT either pre- or postoperatively with doses ranging from 5 to 50.4 Gy (median 25.2 Gy). Twenty patients received 5-fluorouracil +/- leucovorin during EBRT. Three patients received additional cycles of 5-fluorouracil +/- leucovorin as maintenance chemotherapy. Thirty males and 21 females with a median age of 55 years (range 31--73 years) were treated. Thirty-four patients have died; the median follow-up in surviving patients is 21 months. The median, 2-yr, and 5-yr actuarial overall survivals are 23 months, 48% and 12%, respectively. The 2-yr actuarial central control (within IOERT field) is 72%. Local control at 2 years has been maintained in 60% of patients. There is a trend toward improved local control in patients who received > or =30 Gy EBRT in addition to IOERT as compared to those who received no EBRT or <30 Gy with 2-yr local control rates of 81% vs. 54%. Distant metastatic disease has developed in 25 patients, and the actuarial rate of distant progression at 2 and 4 years is 56% and 76%, respectively. Peripheral neuropathy was the main IOERT-related toxicity; 16 (32%) patients developed neuropathies (7 mild, 5 moderate, 4 severe). Ureteral narrowing or obstruction occurred in seven patients. All but one patient with neuropathy or ureter fibrosis received IOERT doses > or =20 Gy. Long-term local control can be obtained in a substantial proportion of patients with aggressive combined modality therapy, but long-term survival is poor due to the high rate of distant metastasis. Re-irradiation with EBRT in addition to IOERT appears to improve local control. Strategies to improve survival in these poor-risk patients may include the more routine use of conventional systemic chemotherapy or the addition of novel systemic therapies.
    No preview · Article · Apr 2001 · International Journal of Radiation OncologyBiologyPhysics

  • No preview · Article · Apr 2001 · Gastroenterology
  • E Radice · Roger R. Dozois
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    ABSTRACT: Local recurrence (LR) varies from less than 4% to greater than 50%; several tumor factors and operative techniques may influence rate of LR. Of greatest interest has been the considerable inter-surgeon variation, even within the same institution. An LR rate of less than 10% has been consistently reported by those who use total mesorectal excision even without any form of adjuvant therapy, either preoperatively or postoperatively. These findings raise important questions about surgical technique, subspecialty teaching, place of adjuvant therapy and quality assurance. The management of LR by a multispecialty team and multimodality treatment including preoperative chemoradiation, surgical resection and intraoperative radiotherapy provides encouraging results in terms of better local control and prolonged survivorship in carefully selected patients. These uncontrolled results justify further evaluation of these salvage operations in a more controlled manner that should include repercussions on the quality of life of the patients.
    No preview · Article · Feb 2001 · Digestive Surgery
  • P Goudet · Roger R. Dozois · K.A. Kelly · D.M. Ilstrup · S.F. Phillips
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    ABSTRACT: Describe the characteristics of extraintestinal manifestations complicating ulcerative colitis present preoperatively and determine their evolution after surgery. Between 1976 and 1986, 281 patients with ulcerative colitis exhibiting one or more extraintestinal manifestations (EIM) before either IPAA (n = 147), Brooke ileostomy (n = 71), Kock pouch (n = 48) or ileorectostomy (n = 15) were assessed retrospectively. The clinical evolution of each manifestation was classified as having disappeared, improved, remained unchanged or aggravated postoperatively. An efficacy index was designed to assess the ratio of the number of cases cured or improved over the number of cases unchanged or aggravated. The relationship between EIM and gender, age, duration of disease and the type of surgery was also ascertained. 433 EIM were observed in 281 patients. The most common were arthralgias of the large joints (n = 146), of the sacroiliac joint (n = 59) and the small joints (n = 51). In comparison to patients without EIM having received the same operation during the same period of time, EIM were seen more often in women, younger patients, than those with longer duration of disease and the ileoanal anastomosis group. 60% had only one EIM at a time. Based on the efficacy index, thromboembolic accidents and erythema nodosum were the most commonly cured or improved. Ocular manifestations and primary sclerosing cholangitis were unaffected. The other EIM responded favorably but variably with improvement in two thirds of patients. The presence of a rectal remnant (IRA) or ileal reservoir did not affect the evolution of the EIM. Thromboembolic complications which are life-threatening, erythema nodosum and arthralgia of the small and large joints which impair quality of life, benefited the most from proctocolectomy. Those conditions may be considered preoperatively when making the decision for surgery.
    No preview · Article · Feb 2001 · Digestive Surgery
  • I E Gecim · B G Wolff · J H Pemberton · R M Devine · R R Dozois
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    ABSTRACT: This study examines the risk factors for developing perianal abscess or fistula formation after ileal pouch-anal anastomosis procedure for chronic ulcerative colitis or familial adenomatous polyposis. A total of 1,457 patients with J-pouch, 1,304 (89.5 percent) with chronic ulcerative colitis and 153 (10.5 percent) with familial adenomatous polyposis who had a two-stage procedure without any evidence of previous perianal disease were included in the study. The effect of pouch-to-anal anastomosis type on perianal abscess or fistula formation was evaluated. A total of 108 patients (7.4 percent) had a perianal abscess or fistula after the ileal pouch-anal anastomosis procedure after at least one year of follow-up. No statistically significant difference was identified in fistula formation regarding the age and gender of the patients (P > 0.05), nor did the risk of fistula formation differ significantly between the patients with handsewn vs. stapled anastomoses (P > 0.05). However, patients with a diagnosis of chronic ulcerative colitis, compared with patients with familial adenomatous polyposis, had a statistically higher risk of developing abscess or fistula (P = 0.012). The most important risk factor in developing perianal sepsis in long-term patients with ileal pouch-anal anastomosis is the initial disease type. After excluding patients without Crohn's disease, the risk of developing an abscess or fistula was found to be significantly greater in patients with chronic ulcerative colitis compared with patients with familial adenomatous polyposis, and this risk is independent of anastomotic technique.
    No preview · Article · Oct 2000 · Diseases of the Colon & Rectum
  • Y R Parc · G Moslein · R R Dozois · J H Pemberton · B G Wolff · J E King
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    ABSTRACT: Virtually all untreated patients with familial adenomatous polyposis develop colorectal carcinoma. Thus, prophylactic colectomy is indicated. Detractors of ileal pouch-anal anastomosis prefer ileorectal anastomosis for teenagers because of the potential negative impact of ileal pouch-anal anastomosis on quality of life. The aim of this study was to assess the effects on quality of life of ileal pouch-anal anastomosis in teenagers with familial adenomatous polyposis. Between 1981 and 1998, 48 teenagers underwent ileal pouch-anal anastomosis for familial adenomatous polyposis. One patient had proctectomy and ileal pouch-anal anastomosis after previous ileorectal anastomosis. A temporary diverting loop ileostomy was established in 42 patients (87.5 percent). One patient had colonic carcinoma diagnosed preoperatively. Two other patients were found to have unsuspected rectal cancer at surgery. Mean follow-up (+/- standard deviation) in 43 patients was 80.5 +/- 42 months. There was no immediate postoperative mortality. Postoperative complications included pelvic sepsis (3 patients; 1 requiring reoperation) and bleeding (1 patient; no surgery required). One patient died of metastatic colonic carcinoma. Ten patients required reoperation, seven had bowel obstruction, one had portal hypertension, and two required an ileostomy. The mean (+/- standard deviation) daytime and nighttime stool frequency was 4 +/- 1.5 and 1 +/- 1, respectively. One patient reported daytime and nighttime incontinence, and two patients reported nighttime incontinence only. No patient experienced impotence or retrograde ejaculation. Social, sexual, sport, housework, recreation, family, travel, and work activities were improved or unchanged in 82.5, 87, 80, 90, 80, 92.5, 77.5, and 89 percent of patients, respectively. Three male patients fathered children, and three female patients had a total of six children after normal pregnancies and deliveries. The impact of ileal pouch-anal anastomosis on quality of life was favorable in the majority of teenagers. The risk of rectal cancer should be the major consideration before proposing an operation to teenagers with familial adenomatous polyposis.
    No preview · Article · Aug 2000 · Diseases of the Colon & Rectum
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    ABSTRACT: To assess long-term outcomes after ileal pouch-anal anastomosis (IPAA) for chronic ulcerative colitis (CUC) with specific emphasis on patient sex, childbirth, and age. Childbirth and the process of aging affect pelvic floor and anal sphincter function independently. Early function after IPAA is good for most patients. Nonetheless, there are concerns about the impact of the aging process as well as pregnancy on long-term functional outcomes after IPAA. Functional outcomes using a standardized questionnaire were prospectively assessed for each patient on an annual basis. Of the 1,454 patients who underwent IPAA for CUC between 1981 and 1994, 1,386 were part of this study. Median age was 32 years. Median length of follow-up was 8 years. Pelvic sepsis was the primary cause of pouch failure irrespective of sex or age. Functional outcomes were comparable between men and women. Eighty-five women who became pregnant after IPAA had pouch function, which was comparable with women who did not have a child. Daytime and nocturnal incontinence affected older patients more frequently than younger ones. Incontinence became more common the longer the follow-up in older patients, but this was not found in younger patients. Poor anal function led to pouch excision in only 3 of 204 older patients. Incontinence rates were significantly higher in older patients after IPAA for CUC compared with younger patients. However, this did not contribute to a greater risk of pouch failure in these older patients. Patient sex and uncomplicated childbirth did not affect long-term functional outcomes.
    Full-text · Article · Jul 2000 · Annals of Surgery
  • YR Parc · RR Dozois · JH Pemberton · BG Wolff

    No preview · Article · Jul 2000 · Diseases of the Colon & Rectum

Publication Stats

10k Citations
890.91 Total Impact Points


  • 1977-2008
    • Mayo Clinic - Rochester
      • • Department of Colon & Rectal Surgery
      • • Department of Surgery
      Rochester, Minnesota, United States
  • 2005
    • Assistance Publique – Hôpitaux de Paris
      Lutetia Parisorum, Île-de-France, France
  • 1998
    • Heinrich-Heine-Universität Düsseldorf
      • Klinik für Unfall- und Handchirurgie
      Düsseldorf, North Rhine-Westphalia, Germany
  • 1991-1993
    • Rochester College
      Rochester, New York, United States
  • 1984
    • St. Joseph's Health Care London
      London, Ontario, Canada
  • 1979
    • University of Minnesota Rochester
      Rochester, Minnesota, United States