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Dive into the research topics where P. Ronan O’Connell is active.

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Featured researches published by P. Ronan O’Connell.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2000

Prospective study of the influence of parity and operative technique on the outcome of primary anal sphincter repair following obstetrical injury.

Myra Fitzpatrick; Michelle Fynes; Mary Cassidy; Michael Behan; P. Ronan O’Connell; Colm O’Herlihy

OBJECTIVE To determine the influence of parity and method of primary anal sphincter repair on outcome following obstetrical third degree perineal tear. STUDY DESIGN Prospective study of 154 women after primary repair following third degree tear conducted over 2 years. Postpartum evaluation included a continence questionnaire, anal manometry and endoanal ultrasound. RESULTS Third degree tears occurred in 1.6% primiparae and 0.6% multiparae during the study period; in 42/112 (38%) primiparae and 10/42 (24%) multiparae, these tears occurred at instrumental deliveries. Mean birthweight (3.8+/-0. 43 kg) was similar in both groups, but prolonged latent second stage of labour (P=0.003), use of epidural analgesia (P<0.0001) and episiotomy extension (P1 quadrant) anal sphincter defect. CONCLUSION Outcome of anal sphincter repair was not influenced by parity or mode of repair. Despite good symptomatic outcomes, ultrasound evidence of significant anal sphincter injury was found in one-third of patients.


Diseases of The Colon & Rectum | 2004

Randomized, clinical trial of bowel confinement vs. laxative use after primary repair of a third-degree obstetric anal sphincter tear.

Rhona Mahony; Michael Behan; Colm O’Herlihy; P. Ronan O’Connell

PURPOSE: Third-degree tears are generally managed by primary anal sphincter repair. Postoperatively, some physicians recommend laxative use, whereas others favor bowel confinement after anorectal reconstructive surgery. This randomized trial was designed to compare a laxative regimen with a constipating regimen in early postoperative management after primary obstetric anal sphincter repair. METHODS: A total of 105 females were randomized after primary repair of a third-degree tear to receive lactulose (laxative group) or codeine phosphate (constipated group) for three days postoperatively. Patients were reviewed at three days and at three months postpartum. Recorded outcome measures were symptomatic and functional outcome and early postoperative morbidity. RESULTS: Forty-nine patients were randomly assigned to the constipated group and 56 patients to the laxative group. The first postoperative bowel motion occurred at a median of four (mean, 4.5 (range, 1–9)) days in the constipated group and at two (mean, 2.5 (range, 1–7)) days in the laxative group (P < 0.001). Patients in the constipated group had a significantly more painful first evacuation compared with the laxative group (P < 0.001). The mean duration of hospital stay was 3.7 (range, 2–6) days in the constipated group and 3.05 days in the laxative group (range, 2–5; P = 0.001). Nine patients in the constipated group complained of troublesome postoperative constipation compared with three in the laxative group (P = 0.033). Continence scores, anal manometry, and endoanal ultrasound findings were similar in the two groups at three months postpartum. CONCLUSIONS: Patients in the laxative group had a significantly earlier and less painful bowel motion and earlier postnatal discharge. There was no difference in the symptomatic or functional outcome of repair between the two regimens.


Annals of Surgery | 2000

Stricture Formation in Crohn’s Disease: The Role of Intestinal Fibroblasts

Mark C. Regan; Brian M. Flavin; John M. Fitzpatrick; P. Ronan O’Connell

OBJECTIVE To determine whether intestinal fibroblasts in patients with Crohns disease (CD) have an enhanced capacity to reorganize collagen and thus cause stricture formation. SUMMARY BACKGROUND DATA Stricture formation is a characteristic feature of CD that may distinguish it from other forms of inflammatory bowel disease. Methods Fibroblasts were obtained at surgery from the colon and ileum of patients with CD and ulcerative colitis (UC) and control patients. Primary fibroblast cultures were obtained by explant technique. Fibroblast contractile activity was measured using fibroblast-populated collagen lattices (FPCLs), in which the cultured fibroblasts were seeded in free-floating collagen gel matrices that they reorganize and contract. Fibroblast contractile activity was measured as the reduction of surface area (mm2) of collagen gel matrix at 24-hour intervals for 1 week. RESULTS Fibroblasts from patients with CD displayed enhanced capacity to contract FPCL when compared to UC and control fibroblasts. This activity was maximal in fibroblasts recovered from strictured regions in CD. Fibroblasts from patients with UC had a contractile capacity similar to that of controls. Hydrocortisone inhibited this in vitro contractile activity in a dose-dependent manner. CONCLUSIONS Intestinal fibroblasts in CD possess enhanced capacity for collagen reorganization and contractile activity in vitro. This activity may be responsible for stricture formation in CD.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2002

Experience with an obstetric perineal clinic

Myra Fitzpatrick; Mary Cassidy; P. Ronan O’Connell; Colm O’Herlihy

OBJECTIVE To review the characteristics of patients attending a dedicated perineal clinic in a maternity hospital. METHODS Case-note review of all new referrals over 2 years 1998 and 1999. RESULTS A total of 399 women were referred with mean age of 34 years (range 18-77), parity of 1.7 (range 1-13) and duration of symptoms of 14 (range 1-156) months. A total of 213 (53%) women were assessed following a recognized third degree perineal tear, 78 (20%) because of fecal incontinence, 45 (11%) for determination of future mode of delivery following a previous perineal injury, 37 (9%) women for treatment of perineal pain and 26 (7%) for other miscellaneous complaints. A total of 83 (21%) required physiotherapy, 42 (11%) received dietetic manipulation, 29 (7%) were treated for perineal pain and 12 (3%) underwent vaginal surgery. A total of 24 (6%) women were referred for consideration of secondary anal sphincter repair and 11 (3%) for specialist gastroenterological investigation. CONCLUSIONS The perineal clinic provides a valuable resource for investigation and treatment of postpartum perineal injury.


Annals of Surgery | 2002

Increased Adhesion Molecule Expression in Serosal Fibroblasts Isolated From Patients with Inflammatory Bowel Disease is Secondary to Inflammation

Ann E. Brannigan; R. William G. Watson; D. Beddy; Hilary Hurley; John M. Fitzpatrick; P. Ronan O’Connell

ObjectiveTo examine the expression of adhesion molecules by serosal and dermal fibroblasts in patients with inflammatory bowel disease. Summary Background DataThe pathophysiologic process that leads to stricture formation in Crohn’s disease (CD) is unknown. Serosal fibroblasts in these patients have an enhanced ability to contract collagen. This property may be reflected in fibroblast adhesion molecule expression, which in turn may be constitutive or secondary to the inflammatory process in patients with CD. MethodsFibroblasts were isolated from inflamed and macroscopically normal serosa of patients with CD or ulcerative colitis (UC) and from normal serosa of patients with colon cancer. Dermal fibroblasts were also isolated from the wound edge. Cell surface and whole cell expression of ICAM-1 were evaluated by flow cytometry and Western blot analysis, respectively. NF&kgr;B was measured by mobility shift assay in parallel experiments. Interleukin 1&bgr; was added to the culture medium. ResultsExpression of ICAM-1 and NF&kgr;B, increased in patients with both CD and UC, was unaltered by interleukin 1&bgr;. The whole cell concentration of ICAM-1 was greater in patients with CD than in patients with UC. Dermal fibroblasts did not display these features. ConclusionsPatients with inflammatory bowel disease display enhanced ICAM-1 expression in serosal fibroblasts but not dermal fibroblasts, indicating a secondary response to inflammation.


Diseases of The Colon & Rectum | 2003

Urinary tract involvement by colorectal cancer.

Deborah McNamara; John M. Fitzpatrick; P. Ronan O’Connell; James M. Church

Abstract PURPOSE: Involvement of the urinary tract by colorectal cancer is sufficiently rare to be encountered by an individual surgeon on an infrequent basis. The aim of this review is to highlight technical and oncologic issues that should be considered when dealing with complex colorectal cancer that involves the urinary tract. METHODS: The relevant literature from 1975 to 2001 was identified using the MEDLINE database of the U.S. National Library of Medicine and reviewed. Because of the diversity of forms of presentation of urologic involvement, few randomized, controlled trials are available, with most evidence derived from retrospective studies. RESULTS: Three distinct clinical situations in which the urinary tract may be affected by colorectal cancer were identified: involvement by primary colorectal cancer, involvement by recurrent cancer, and unexpected intraoperative findings of urinary tract involvement. Management strategies to identify and treat locally advanced primary or recurrent colorectal cancer involving the urinary tract improve survival with acceptable morbidity and mortality. Careful preoperative assessment of all patients with colorectal cancer will reduce unexpected identification of urinary tract invasion at the time of surgery. In patients in whom cure is not possible, endourologic techniques combined with judicious surgical resection can provide high-quality palliation. Optimal care of many of these conditions is facilitated by specialist urologic advice. CONCLUSIONS: The wide spectrum of possible urinary tract involvement by colorectal cancer requires individual patient-specific and disease-specific consideration. The literature offers important guidelines that aid decision making and improve management of these challenging problems.


Diseases of The Colon & Rectum | 2017

Systematic Review of Animal Models Used in Research of Origins and Treatments of Fecal Incontinence

J. Evers; James F. X. Jones; P. Ronan O’Connell

BACKGROUND: Fecal incontinence is a common disorder, but its pathophysiology is not completely understood. OBJECTIVE: The aim of this review is to present animal models that have a place in the study of fecal incontinence. DATA SOURCES: A literature review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines performed in August 2016 revealed 50 articles of interest. Search terms included fecal/faecal incontinence and animal model or specific species. STUDY SELECTION: Articles not describing an animal model, in vitro studies, veterinary literature, reviews, and non-English articles were excluded. MAIN OUTCOME MEASURES: The articles described models in rats (n = 31), dogs (n = 8), rabbits (n = 7), and pigs (n = 4). RESULTS: Different fecal incontinence etiologies were modeled, including anal sphincter lesions (33 articles) ranging from a single anal sphincter cut to destruction of 50% of the anal sphincter by sharp dissection, electrocautery, or diathermy. Neuropathic fecal incontinence (12 articles) was achieved by complete or incomplete pudendal, pelvic, or inferior rectal nerve damage. Mixed fecal incontinence (5 articles) was modeled either by the inflation of pelvic balloons or an array of several lesions including nervous and muscular damage. Anal fistulas (2 articles), anal sphincter resection (3 articles), and diabetic neuropathy (2 articles) were studied to a lesser extent. LIMITATIONS: Bias may have arisen from the authors’ own work on fecal incontinence and the absence of blinding to the origins of articles. CONCLUSIONS: Validated animal models representing the main etiologies of fecal incontinence exist, but no animal model to date represents the whole pathophysiology of fecal incontinence. Therefore, the individual research questions still dictate the choice of model and species.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2003

Anal sphincter disruption at vaginal delivery: is recurrence predictable?

Rosemary Harkin; Myra Fitzpatrick; P. Ronan O’Connell; Colm O’Herlihy


Journal of The American College of Surgeons | 2004

Critical involvement of stress-activated mitogen-activated protein kinases in the regulation of intracellular adhesion molecule-1 in serosal fibroblasts isolated from patients with Crohn's disease.

D. Beddy; William Watson; John M. Fitzpatrick; P. Ronan O’Connell


Diseases of The Colon & Rectum | 2012

Sacral Nerve Stimulation for Fecal Incontinence: At a Crossroad and Future Challenges

Yasuko Maeda; P. Ronan O’Connell; Klaus E. Matzel; Søren Laurberg

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Michael Behan

Mater Misericordiae Hospital

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D. Beddy

Mater Misericordiae Hospital

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Mary Cassidy

University College Dublin

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Ann E. Brannigan

Mater Misericordiae Hospital

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J. Evers

University College Dublin

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Mark C. Regan

Mater Misericordiae Hospital

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