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Dive into the research topics where Manuel Valero is active.

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Featured researches published by Manuel Valero.


Endoscopy | 2018

Reliability and accuracy of a novel classification system using peroral cholangioscopy for the diagnosis of bile duct lesions

Carlos Robles-Medranda; Manuel Valero; Miguel Soria-Alcivar; Miguel Puga-Tejada; Roberto Oleas; Jesenia Ospina-Arboleda; Haydee Alvarado-Escobar; Jorge Baquerizo-Burgos; Carlos Robles-Jara; Hannah Pitanga-Lukashok

BACKGROUND The aim of this study was to propose a novel, comprehensive, macroscopic classification for bile duct lesions. METHODS A two-stage protocol was designed. In Stage I, a retrospective study (September 2013 to September 2015) of patients with bile duct lesions detected by peroral cholangioscopy (POCS) was performed. A total of 315 images with at least 6 months of follow-up were recorded, analyzed, and correlated to histology, and were classified as non-neoplastic (one of three types, 1 - 3) or neoplastic (one of four types, 1 - 4) based on morphological and vascular patterns. In Stage II, a prospective, nonrandomized, double-blind study was performed from December 2015 to December 2016 to validate the proposed classification. Sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), and positive and negative likelihood ratios (LR + and LR - , respectively) were calculated (gold standard: 6-month follow-up). Inter- and intraobserver agreement (kappa value, κ) among experts and non-experts were calculated. RESULTS 171 patients were included (65 retrospective; 106 prospective). In Stage I, 28/65 cases were neoplastic and 37 /65 were non-neoplastic, according to the final diagnosis. In Stage II, 56/106 were neoplastic with a sensitivity, specificity, PPV, NPV, LR + , and LR - for neoplastic diagnosis of 96.3 %, 92.3 %, 92.9 %, 96 %, 12.52, and 0.04, respectively. The proposed classification presented high reproducibility among observers, for both neoplastic and subtypes categories. However, it was better for experts (κ > 80 %) than non-experts (κ 64.7 % - 81.9 %). CONCLUSION The novel classification system could help physicians to distinguish non-neoplastic from neoplastic bile duct lesions.


World Journal of Gastrointestinal Endoscopy | 2017

Endoscopic ultrasound in oncology: An update of clinical applications in the gastrointestinal tract

Manuel Valero; Carlos Robles-Medranda

An accurate staging is necessary to select the best treatment and evaluate prognosis in oncology. Staging usually begins with noninvasive imaging such as computed tomography, magnetic resonance imaging or positron emission tomography. In the absence of distant metastases, endoscopic ultrasound plays an important role in the diagnosis and staging of gastrointestinal tumors, being the most accurate modality for local-regional staging. Its use for tumor and nodal involvement in pre-surgical evaluation has proven to reduce unnecessary surgeries. The aim of this article is to review the current role of endoscopic ultrasound in the diagnosis and staging of esophageal, gastric and colorectal cancer.


World Journal of Gastrointestinal Endoscopy | 2017

Clinical impact of confocal laser endomicroscopy in the management of gastrointestinal lesions with an uncertain diagnosis.

Carlos Robles-Medranda; Maria Vargas; Jesenia Ospina; Miguel Puga-Tejada; Manuel Valero; Miguel Soria; Gladys Bravo; Carlos Robles-Jara; Hannah P. Lukashok

AIM To evaluate the clinical impact of confocal laser endomicroscopy (CLE) in the diagnosis and management of patients with an uncertain diagnosis. METHODS A retrospective chart review was performed. Patients who underwent CLE between November 2013 and October 2015 and exhibited a poor correlation between endoscopic and histological findings were included. Baseline characteristics, indications, previous diagnostic studies, findings at the time of CLE, clinical management and histological results were analyzed. Interventions based on CLE findings were also analyzed. We compared the diagnostic accuracy of CLE and target biopsies of surgical specimens. RESULTS A total of 144 patients were included. Of these, 51% (74/144) were female. The mean age was 51 years old. In all, 41/144 (28.4%) lesions were neoplastic (13 bile duct, 10 gastric, 8 esophageal, 6 colonic, 1 duodenal, 1 rectal, 1 ampulloma and 1 pancreatic). The sensitivity, specificity, positive predictive value, negative predictive value, and observed agreement when CLE was used to detect N-lesions were 85.37%, 87.38%, 72.92%, 93.75% and 86.81%, respectively. Cohen’s Kappa was 69.20%, thus indicating good agreement. Changes in management were observed in 54% of the cases. CONCLUSION CLE is a new diagnostic tool that has a significant clinical impact on the diagnosis and treatment of patients with uncertain diagnosis.


Gastrointestinal Endoscopy | 2018

Su1373 UTILITY OF LIVER AND SPLEEN EUS-ELASTOGRAPHY AS A DIAGNOSTIC TOOL FOR PREDICTING LIVER CIRRHOSIS AND PORTAL HYPERTENSION: A CASE-CONTROL DIAGNOSTIC TRIAL

Carlos Robles-Medranda; Manuel Valero; Miguel Puga-Tejada; Roberto Oleas; Joao A. Nebel; Sylon R. De Britto; Jesenia Ospina; Miguel Soria ALcívar; Haydee Alvarado; Raquel S. Del Valle; Hannah P. Lukashok


Gastrointestinal Endoscopy | 2018

1036 COILS + CYANOACRYLATE VS. COILS ALONE IN THE ENDOSCOPIC ULTRASOUND-GUIDED MANAGEMENT OF GASTRIC VARICES [GOV II AND IGV I]: A RANDOMIZED, CONTROLLED THERAPEUTIC TRIAL.

Carlos Robles-Medranda; Manuel Valero; Miguel Soria ALcívar; Miguel Puga-Tejada; Roberto Oleas; Sylon R. De Britto; Joao A. Nebel; Jesenia Ospina; Haydee Alvarado; Raquel S. Del Valle; Hannah P. Lukashok


Gastroenterology | 2018

Tu1722 - First Spanish Validated Translation of a Single Health-Related Quality of Life Survey for Broad use Across Different Chronic Esophageal Diseases: A Psychometric Evaluation of the Neqol Survey in an Ecuadorian Population

Roberto Oleas; Hannah P. Lukashok; Miguel Puga-Tejada; Manuel Valero; Maria Sanchez-Carriel; Andrea Acosta-Crow; Jesenia Ospina; Guillermo Muñoz Jurado; Haydee Alvarado; Miguel Soria ALcívar; Raquel S. Del Valle; Rocio Canola-Cortez; Carlos Robles-Medranda


Pancreatology | 2017

Critical analysis of strain ratio cut-off value in diagnostic perfomance of EUS-Elastography defining malignant pancreatic lesions and lymph nodes

Manuel Valero; Miguel Puga-Tejada; Jesenia Ospina Arboleda; Raquel del Valle Zabala; Gladys Bravo Velez; Miguel Soria ALcívar; Hannah P. Lukashok; Carlos Robles-Medranda


Gastrointestinal Endoscopy | 2017

1139 Management of Complicated Variceal Bleeding When Standard Endoscopic Techniques Have Failed: Clips, Stents?

Carlos Robles-Medranda; Manuel Valero; Miguel Soria ALcívar; Miguel Puga-Tejada; Haydee Alvarado; Jesenia Ospina; Hannah P. Lukashok


Gastrointestinal Endoscopy | 2017

Tu1429 Association of Obesity With IBD Disease Location, Severity, and Treatment Course: A Single-Center Cohort Study

Carlos Robles-Medranda; Miguel Soria ALcívar; Miguel Puga-Tejada; Jesenia Ospina; Manuel Valero; Haydee Alvarado; Hannah P. Lukashok


Gastrointestinal Endoscopy | 2017

1109 The Use of Angiography as a Modification of the Eus-Guided Injection of Cyanoacrylate With Coils Technique for Gastric Varices Treatment

Carlos Robles-Medranda; Manuel Valero; Miguel Puga-Tejada; Miguel Soria ALcívar; Guillermo Muñoz Jurado; Jesenia Ospina; Hannah P. Lukashok

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Carlos Robles-Medranda

Federal University of Rio de Janeiro

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Hannah P. Lukashok

Federal University of Rio de Janeiro

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Miguel Puga-Tejada

Catholic University of Santiago de Guayaquil

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Roberto Gugig

University of California

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