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BACKGROUND: Endoscopic resection (ER) with or without ablation is the first choice treatment for early Barrett's neoplasia. Adequate staging is important to assure a good oncological outcome. OBJECTIVE: The purpose of this study was to investigate the diagnostic accuracy of pre-operative biopsies in patients who undergo ER for high-grade dysplasia (HGD) or early adenocarcinoma (EAC) in Barrett's oesophagus (BE) and the cardia. METHODS: Between November 2005-May 2012, 142 ERs performed in 137 patients were obtained. Worst pre-ER and ER histology were compared. Upgrading/downgrading was defined as any more/less severe histological grading on the ER specimen. RESULTS: The accuracy of pre-ER biopsies in predicting final histology was 61%. ER changed the pre-treatment diagnosis in 55 of the 142 procedures (39%) with downgrading in 23 cases (16%) and upgrading from HGD to T1a or T1b in 32 cases (23%). In the majority of upgraded cases, a visible lesion according to the Paris classification could be detected (26/32, 81%). CONCLUSION: The diagnostic accuracy of oesophageal biopsies alone in predicting final pathology in Barrett's dysplasia is only 61%. The majority of upgraded lesions are detectable. When ablative therapy is considered in HGD Barrett's dysplasia a meticulous inspection for and removal of all small visible lesions is mandatory.
RESUMEN
The present experimental study is aimed at a combined uniaxial and biaxial mechanical characterization of the deformation behavior of two types of prosthetic meshes, SPMM (heavy-weight) and Gynemesh M (light-weight, partly absorbable), after integration in the host tissue. Explants from a full-thickness-abdominal-wall-defect-rabbit-model were tested in the two loading conditions. Corresponding protocols and data analysis procedures for biaxial inflation tests and uniaxial tensile tests were developed. Biaxial responses were observed to be by factor 2-4 stiffer compared to corresponding uniaxial experiments, depending on the material tested. In biaxial loading conditions, SPMM explants were stiffest. Gynemesh M explants and native tissue were similarly compliant at low membrane tensions (<5N/cm) (abdominal wall: 40±23N/cm, Gynemesh M: 59±44N/cm, SPMM: 145±36N/cm). At high membrane tensions (>5N/cm), there were distinct differences in the stiffness of the three groups, SPMM explants being the stiffest, followed by Gynemesh M explants and native tissue being the most compliant. In uniaxial loading conditions, the two explants were similarly stiff and distinctly stiffer than native tissue at low membrane tensions (<5N/cm) (abdominal wall: 9±1N/cm, Gynemesh M: 21±5N/cm, and SPMM: 24±5N/cm). At high membrane tension (>5N/cm), differences between all groups vanished. Biaxial and uniaxial tests yield different results with respect to the mechanical behavior of mesh explants. These findings demonstrate that an evaluation of the mechanical biocompatibility of prosthetic meshes should be based on an experimental configuration (uniaxial or biaxial tension) which reproduces the expected in vivo conditions of mechanical loading and deformation.
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Prótesis e Implantes , Textiles , Pared Abdominal , Animales , Fenómenos Biomecánicos , Dioxanos , Poliésteres , Polipropilenos , ConejosRESUMEN
OBJECTIVE: To determine whether anisotropy persisted after incorporation into the host, using a standardised rabbit model for abdominal wall reconstruction. DESIGN: Investigator-initiated prospective-controlled experimental study. SETTING: Centre for Surgical Technologies, Medical Faculty KU-Leuven. SAMPLE: Fifteen New Zealand White rabbits. METHODS: In each rabbit, four full thickness primarily repaired abdominal wall defects were covered by a 4 × 5-cm Prolift+M implant (Johnson & Johnson, Norderstedt, Germany), either with the stiffest (n = 6 rabbits) or most elastic (n = 6) direction parallel to the body axis. Prolift+M contains 32 g/m² polypropylene, reinforced with polyglecaprone fibres. Harvesting was performed after 30, 60 and 120 days (n = 2 each time-point). The abdominal wall of three unoperated rabbits was used as negative control. MAIN OUTCOME MEASURES: Contraction, compliance and maximal strain and stress determined by uniaxial tensiometry. RESULTS: Anisotropy properties persist at lower, more physiological displacements, but not at higher displacements. The stiffness of a mesh-augmented repair in the lower strain range remains above that of native tissue. Eventual mesh contraction was limited to 4.3%. CONCLUSIONS: Anisotropic properties of Prolift+M persist in vivo and shrinkage is minimal. Compliance of mesh-augmented repair remains less than that of native tissue. The functional consequences of this remain to be studied.
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Pared Abdominal/cirugía , Polipropilenos , Prótesis e Implantes , Mallas Quirúrgicas , Animales , Anisotropía , Fenómenos Biomecánicos , Conejos , Procedimientos de Cirugía Plástica , Estrés MecánicoRESUMEN
Laparoscopy offers great exposure and surgical detail, reduces blood loss and the need for excessive abdominal packing and bowel manipulation making it an excellent modality to perform pelvic floor surgery. Laparoscopic repair of level I or apical vaginal prolapse may be challenging, due to the need for extensive dissection and advanced suturing skills. However it offers the efficacy of open abdominal sacrocolpopexy, such as lower recurrence rates and less dyspareunia than sacrospinous fixation, as well as the reduced morbidity of a laparoscopic approach.
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Laparoscopía/métodos , Diafragma Pélvico/cirugía , Prolapso Uterino/cirugía , Femenino , Procedimientos Quirúrgicos Ginecológicos/métodos , HumanosRESUMEN
Laparoscopy offers great exposure and surgical detail, reduces blood loss and the need for excessive abdominal packing-- and bowel manipulation making it an excellent modality to perform pelvic floor surgery. Laparoscopic repair of level I or apical vaginal prolapse may be challenging, due to the need for extensive dissection and advanced suturing skills. However, it offers the efficacy of open abdominal sacrocolpopexy, such as lower recurrence rates and less dyspareunia-- than sacrospinous fixation, as well as the reduced morbidity of a laparoscopic approach.