L. Ramos

Clinical validation of the European Panel on the Appropriateness of Gastrointestinal Endoscopy (EPAGE) II criteria in an open-access unit: a prospective study.

BACKGROUND AND STUDY AIMS The European Panel on the Appropriateness of Gastrointestinal Endoscopy (EPAGE I) criteria were recently updated (EPAGE II), but no prospective studies have used these criteria in clinical practice. The aim of the current study was to validate the EPAGE II criteria in an open-access endoscopy unit. PATIENTS AND METHODS A prospective observational study was conducted in an open-access endoscopy unit at a tertiary care referral center. Consecutive outpatients (n = 1004; mean age 58.9 ± 13.1 years; 45 % men) were referred for diagnostic colonoscopy between September 2009 and February 2010. The appropriateness of colonoscopy was assessed based on EPAGE II criteria, and the relationship between appropriateness and both referral doctor and detection of significant lesions was examined. The effectiveness of EPAGE II criteria in assessing appropriateness was measured by means of sensitivity, specificity, and positive and negative predictive values for detecting significant lesions. RESULTS Colonoscopic cecal intubation was achieved in 956 patients (95.2 %). Most referral doctors were gastroenterologists (58.0 %) and the most common indication was colorectal cancer (CRC) screening (35.2 %). EPAGE II criteria were applicable in 968 patients (96.4 %); of these patients, the indication was appropriate in 778 (80.4 %), inappropriate in 102 (10.5 %), and uncertain in 88 (9.1 %). Patients with appropriate or uncertain indications based on EPAGE II criteria had more relevant endoscopic findings than those with inappropriate indications (38.8 % vs. 24.5 %; OR 1.95, 95 %CI 1.22 - 3.13; P < 0.005). Sensitivity and negative predictive value of EPAGE II criteria for detecting significant lesions were 93.1 % (95 %CI 90 % - 96 %) and 75.5 % (95 %CI 67 % - 84 %), respectively, whereas for advanced neoplastic lesions these values were 98.0 % (95 %CI 95 % - 100 %) and 98.0 % (95 % CI 95 % - 100 %), respectively. Adherence to EPAGE II recommendations was an independent predictor of finding a significant lesion (OR 1.93, 95 %CI 1.20 - 3.11; P = 0.007). CONCLUSIONS EPAGE II is a simple, valid score for detecting inappropriate colonoscopies in clinical practice.

Microstructural characterization of an eutectic Al-Si-Ni alloy treated by laser surface remelt

This work aims to analyze the effects of the Laser Surface Remelt Treatment (LSR) on Al-11%Si-5%Ni alloys microhardness and microstructure. The operational parameters of the laser involved in the treatment were scanning speed (V) and power (P). Fourteen tracks resulting from the combination of these parameters were analyzed by optical and scanning electronic microscopes (OM and SEM, respectively), observing the dimensions of the remelted pool and the change in the microstructure. Vickers microhardness tests were conducted to examine the effects of LSR on the surface and X-ray diffraction (XRD) was performed on treated and non-treated alloy samples to examine the present phases. The increase in P resulted in the increase in the pool dimensions, while the increase in V presented the opposite effect. The LSR was very effective in the refinement of α-Al dendrites and interdendritic eutectic region, with a minimum primary dendritic spacing of 0,86 μm. The Vickers microhardness increased up to 105% for sigle tracks and 76% for overlapped tracks, comparing to conventional casting.