Padraic Mac Mathuna
Mater Misericordiae University Hospital
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Featured researches published by Padraic Mac Mathuna.
Gastrointestinal Endoscopy | 1995
Padraic Mac Mathuna; Peggy White; Eileen Clarke; R. Merriman; John Lennon; John Crowe
BACKGROUND Because sphincterotomy accounts for a major portion of the morbidity and mortality associated with ERCP, we have proposed endoscopic balloon papillary dilation or sphincteroplasty as an alternative. METHODS We report the outcome in a series of 100 patients in whom balloon sphincteroplasty was attempted for bile duct stones up to 20 mm in diameter, with a median follow-up of 16 months (range 6 to 30). RESULTS During one ERCP session using sphincteroplasty alone, the bile duct was cleared in 78%, mechanical lithotripsy being required in 10% for stones greater than 12 mm in diameter. Incomplete duct clearance was achieved in a further 4%, all of whom underwent repeat ERCP with successful duct clearance without recourse to sphincterotomy. Failure to clear the bile duct with sphincteroplasty in the remaining 18% was primarily related to large stone size ( > 15 mm). Sphincterotomy was required to clear the duct in 7%. Another 6% comprised elderly high-risk patients with multiple large stones greater than 15 mm who were treated by stent insertion plus ursodeoxycholic acid. No papillary hemorrhage was observed; uncomplicated pancreatitis occurred in 5%. During a median follow-up of 16 months, 2% had recurrent symptomatic bile duct stones considered to have been unrecognized following the initial ERCP: these were removed after repeat sphincteroplasty. No clinical evidence of papillary stenosis was observed during follow-up. CONCLUSIONS Endoscopic balloon papillary dilation or sphincteroplasty is a safe and effective alternative to sphincterotomy in the management of bile duct stones less than 12 mm; larger stones may require mechanical lithotripsy to facilitate duct clearance.
Gastrointestinal Endoscopy | 1996
Padraic Mac Mathuna; David Siegenberg; David Gibbons; Daniel Gorin; Michael J. O'Brien; Nezem A. Afdhal; Ram Chuttani
BACKGROUND Balloon dilation or sphincteroplasty is emerging as a potentially safe and effective alternative to sphincterotomy in the management of bile duct stones. However, concerns related to the possible development of fibrosis or papillary stenosis led us to investigate the acute and long-term effects of balloon sphincteroplasty on papillary structure. METHODS Sixteen pigs (45 to 50 kg) underwent transduodenal cannulation of the bile duct while under general anesthesia. Balloon sphincteroplasty was performed in 10 pigs to a diameter of 8 mm at a pressure of 10 atm. Sphincterotomy was carried out in 3 pigs while 2 other untreated pigs acted as controls. Eleven animals were sacrificed at intervals from 15 to 120 minutes after balloon sphincteroplasty or sphincterotomy. The remaining 5 animals were sacrificed between 6 and 12 weeks later. Histologic sections through the papilla were assessed for evidence of morphologic changes. RESULTS When compared with controls, sections taken 15 to 120 minutes after balloon sphincteroplasty showed a progressive increase in acute inflammation extending transmurally. Intramucosal, but no transmural, hemorrhage was noted. No architectural distortion or smooth muscle disruption was observed in contrast to the transmural hemorrhage, smooth muscle disruption, and mucosal necrosis seen following sphincterotomy. After 6 to 12 weeks, mild chronic inflammation with follicular hyperplasia was present but no smooth muscle disruption or fibrosis was observed. CONCLUSION Balloon sphincteroplasty causes an acute transmural inflammatory response and chronic follicular hyperplasia but is not associated with fibrosis or altered papillary architecture.
Journal of Gastroenterology and Hepatology | 2000
Gerard Clarke; Eleanor Ryan; J.Conor O'Keane; John Crowe; Padraic Mac Mathuna
Background and Aims : In the absence of other metastatic disease, the presence of lymph node metastasis remains the most important determinant of survival in colorectal cancer (CRC). Cluster designation 44 variant 6 (CD44v6) over‐expression is associated with worse outcome in all stages of CRC. The CD44v6 is believed to confer metastatic potential through its facilitation of migration, extravasation and proliferation, although the specific means by which it conveys an adverse prognosis in CRC is unknown. The aim of the present study was to determine if CD44v6 over‐expression in Stage II CRC subjects was associated with the presence of lymph node micrometastases.
Journal of Clinical Oncology | 2016
Grainne M. O'Kane; Sarah A. McGarrigle; Nadia Rehill; Michael Farrell; Jacintha O'Sullivan; C. Muldoon; Padraic Mac Mathuna; Desmond N. Carney; David James Gallagher
582 Background: Lynch Syndrome (LS) is caused by germline mutations in mismatch repair genes (MMR) genes which are critical in maintaining cellular integrity. Failure of the MMR pathway in LS culminates in the hypermutable phenotype of Microsatellite Instability. LS confers an increased risk of malignancy of which colorectal cancer (CRC) is most common. Carriers exhibit significant phenotypic variation in the age of onset of malignancy which cannot be predicted. Telomere length attrition is considered an early step in carcinogenesis and may be accelerated by oxidative stress. We investigated an association between relative telomere length (RTL) and levels of DNA oxidative damage in LS affected carriers (AC), unaffected carriers (UAC) and in patients with MMR- proficient colorectal cancer (MPC). Methods: Peripheral blood mononuclear cells were isolated from patients within each group. DNA was extracted and RTL measured by quantitative polymerase chain reaction (PCR). Real-Time PCR was used to quantitate ex...
Journal of Clinical Oncology | 2017
Grainne M. O'Kane; Sarah A. McGarrigle; Simon Hooper; Michael Farrell; Jacinta O'Sullivan; C. Muldoon; Padraic Mac Mathuna; Desmond N. Carney; David James Gallagher
Journal of Clinical Oncology | 2017
Sarah A. McGarrigle; Grainne M. O'Kane; Simon Hooper; Nadia Rehill; Michael Farrell; Jacinta O'Sullivan; C. Muldoon; Padraic Mac Mathuna; Desmond N. Carney; David James Gallagher
Journal of Clinical Oncology | 2013
Michael Farrell; Tomas Lyons; Darragh S Gogarty; Naoise Maria Dorman; Loretto O' Brien; Padraic Mac Mathuna; David James Gallagher
Gastroenterology | 2013
Margaret Walshe; Michael Farrell; Tomas G. Lyons; Darragh S Gogarty; Naoise Maria Dorman; David Hughes; Loretta O'Brien; Jasmin Schmid; Philip S. Boonstra; Bhramar Mukherjee; David James Gallagher; Padraic Mac Mathuna
Gastroenterology | 2013
Anna E. Smyth; Ciaran F. Healy; Padraic Mac Mathuna; Helen M. Fenlon
Gastroenterology | 2012
Conor Lahiff; Niall Mulligan; Peter Doran; David W. Murray; Graham P. Pidgeon; John V. Reynolds; Padraic Mac Mathuna