Inteligencia artificial en la colonoscopia de tamizaje y la disminución del error.

Artificial Intelligence (AI) has the potential to change many aspects of healthcare practice. Image discrimination and classification has many applications within medicine. Machine learning algorithms and complicated neural networks have been developed to train a computer to differentiate between normal and abnormal areas. Machine learning is a form of AI that allows the platform to improve without being programmed. Computer Assisted Diagnosis (CAD) is based on latency, which is the time between the captured image and when it is displayed on the screen. AI-assisted endoscopy can increase the detection rate by identifying missed lesions. An AI CAD system must be responsive, specific, with easy-to-use interfaces, and provide fast results without substantially prolonging procedures. AI has the potential to help both, trained and trainee endoscopists. Rather than being a substitute for high-quality technique, it should serve as a complement to good practice. AI has been evaluated in three clinical scenarios in colonic neoplasms: the detection of polyps, their characterization (adenomatous vs. non-adenomatous) and the prediction of invasive cancer within a polypoid lesion.

La inteligencia artificial (IA) tiene el potencial de cambiar muchos aspectos de la práctica sanitaria. La discriminación y la clasificación de imágenes tiene muchas aplicaciones dentro de la medicina. Se han desarrollado algoritmos de aprendizaje automático y redes neuronales complicadas para entrenar a una computadora a diferenciar las áreas normales de las anormales. El aprendizaje automático es una forma de IA que permite que la plataforma mejore sin ser programada. El diagnóstico asistido por computadora (CAD) se basa en latencia, que es el tiempo entre la imagen capturada y cuando es mostrada en la pantalla. La endoscopia asistida por IA puede incrementar la tasa de detección al identificar lesiones obviadas. Un sistema CAD de IA debe ser sensible, específico, con interfaces fáciles de usar, y proporcionar resultados rápidos sin prolongar sustancialmente los procedimientos. La IA tiene el potencial de ayudar tanto a endoscopistas entrenados como a los que están en entrenamiento. En vez de ser un sustituto para una técnica de alta calidad, deberá servir como un complemento de las buenas prácticas. La IA ha sido evaluada en tres escenarios clínicos en las neoplasias colónicas: la detección de pólipos, su caracterización (adenomatosos vs. no adenomatosos) y la predicción de cáncer invasor dentro de una lesión polipoide.

Gastric variceal bleeding treated through endoscopic ultrasound-guided coiling and N-butyl-2-cyanoacrylate application.

OBJECTIVE: To evaluate efficacy and safety between dual angiotherapy (endocoil plus N-butyl-cyanoacrylate) guided by endoscopic ultrasound) versus N-butyl-cyanoacrylate in the secondary prophylaxis of gastroesophageal varices (GOV). METHOD: Prospective non-inferiority study comparing two gastric variceal eradication techniques. We evaluated technical and clinical success, GOV occlusion and eradication, rebleeding, reoperation, GOV-free period, complications, and mortality. Chi square for categorical variables and Student's t for numerical variables with a significance level of 0.05. RESULTS: There were 68 patients (average age 55.5 ± 10 years, women 44 (64.7%) and average body mass index 25.7 ± 3.5 kg/m2). The most frequent cause was alcoholic steatohepatitis (58%). Dual therapy had greater technical (100% vs. 94.3%) and clinical (100% vs. 85%) success. Obliteration was faster (100 vs. 79.2%). This group only required one session. The GOV size was 24 ± 14 mm and 1-2 endocoils were placed. The median follow-up was 221 days. The reoperation-free rate was high (100% vs. 94%; p = 0.9). CONCLUSIONS: Dual angiotherapy guided by endoscopic ultrasound and cyanoacrylate injection are effective for the eradication of GOV without differences in adverse event rates.

OBJETIVO: Evaluar la eficacia y la seguridad de la angioterapia dual (endo-coil más N-butil-cianoacrilato) guiada por ultrasonido endoscópico) frente a N-butil-cianoacrilato solo en la profilaxis secundaria de várices gásctricas. MÉTODO: Estudio prospectivo de no inferioridad comparando dos técnicas de erradicación de várices gástricas. Se evalúan el éxito técnico y clínico, la oclusión y la erradicación de GOV, el resangrado, la reintervención, el período libre de GOV, las complicaciones y la mortalidad. Análisis estadístico mediante prueba de χ2 para variables categóricas y t de Student para las numéricas, con nivel de significancia de 0.05. RESULTADOS: Fueron 68 pacientes (edad promedio 55.5 ± 10 años, mujeres 44 (64.7%) e índice de masa corporal promedio 25.7 ± 3.5 kg/m2). La causa más frecuente fue esteatohepatitis alcohólica (58%). La terapia dual tuvo mayor éxito técnico (100% vs. 94.3%) y clínico (100% vs. 85%), y la obliteración fue más rápida (100 vs. 79.2%); este grupo solo requirió una sesión. El tamaño de las GOV fue de 24 ± 14 mm y se colocaron uno o dos endo-coils. La mediana de seguimiento fue de 221 días. La tasa de libres de reintervención fue alta (100% vs. 94%; p = 0.9). CONCLUSIONES: La angioterapia dual guiada por ultrasonido y la inyección de cianoacrilato son efectivas para la erradicación de las GOV, sin diferencias en las tasas de eventos adversos.

Usefulness of optical enhancement endoscopy combined with magnification to improve detection of intestinal metaplasia in the stomach.

Background and study aims The light blue crest observed in narrow band imaging endoscopy has high diagnostic accuracy for diagnosis of gastric intestinal metaplasia (GIM). The objective of this prospective study was to evaluate the diagnostic accuracy of magnifying i-scan optical enhancement (OE) imaging for diagnosing the LBC sign in patients with different levels of risk for gastric cancer in a Mexican clinical practice. Patients and methods Patients with a history of peptic ulcer and symptoms of dyspepsia or gastroesophageal reflux disease were enrolled. Diagnosis of GIM was made at the predetermined anatomical location and white light endoscopy and i-scan OE Mode 1 were captured at the two predetermined biopsy sites (antrum and pyloric regions). Results A total of 328 patients were enrolled in this study. Overall GIM prevalence was 33.8 %. The GIM distribution was 95.4 % in the antrum and 40.5 % in the corpus. According to the Operative Link on Gastritis/Intestinal-Metaplasia Assessment staging system, only two patients (1.9 %) were classified with high-risk stage disease. Sensitivity, specificity, positive​ and negative predictive values, positive and negative likelihood ratios, and accuracy of both methods (95 % C. I.) were 0.50 (0.41-0.60), 0.55 (0.48-0.62), 0.36 (0.31-0.42), 0.68 (0.63-0.73), 1.12 (0.9-1.4), 0.9 (0.7-1.1), and 0.53 (0.43-0.60) for WLE, and 0.96 (0.90-0.99), 0.91 (0.86-0.94), 0.84 (0.78-0.89), 0.98 (0.94-0.99), 10.4 (6.8-16), 0.05 (0.02-0.12), and 0.93 (0.89-0.95), respectively. The kappa concordance was 0.67 and the reliability coefficient was 0.7407 for interobserver variability. Conclusions Our study demonstrated the high performance of magnifying i-scan OE imaging for endoscopic diagnosis of GIM in Mexican patients.

Results of the fecal immunochemical test in a colorectal cancer screening program in Mexico.

BACKGROUND: Colorectal cancer (CRC) is one of the main five causes of morbidity and mortality by oncologic diseases in our country and worldwide. Recently, fecal immunochemical test (FIT) has proven to be a noninvasive screening test that allows to select patients most likely to have a pre-malign lesion in order to perform a colonoscopy. OBJECTIVE: To report the findings of a CRC screening program using FIT in our country population. METHOD: A multicentric study was performed, by inviting open population older than 50 years to participate in a CRC screening. Quantitative FIT specific for human hemoglobin was used, with a cut point of 100 ng/ml or higher to consider as positive. Those patients with positive results were asked to undergo a colonoscopy. In the cases where polypoid lesions were found, biopsies were performed. RESULTS: In total, 751 FIT were processed, and 51 (6.8) of those were positive, with a rate of 15.9 premalign lesions for 1,000 individuals, and 1.3 patients with CRC for every 1,000. CONCLUSIONS: The present study matches worldwide reports, supporting the initiative of establishing a formal and standardized CRC screening program in the public health sector.

ANTECEDENTES: El cáncer colorrectal (CCR) es una de las cinco primeras causas de morbimortalidad por cáncer en nuestro país y en todo el mundo. La prueba inmunoquímica fecal (FIT, fecal immunochemical test) es una herramienta de tamizaje no invasiva que permite seleccionar a los sujetos con mayor probabilidad de lesión premaligna en la colonoscopia. OBJETIVO: Reportar los resultados del programa de escrutinio para CCR mediante FIT en población abierta en México. MÉTODO: Estudio multicéntrico nacional en población abierta mayor de 50 años a través de medios de difusión masiva para participar en un programa de escrutinio de CCR. Se utilizó FIT cuantitativa específica para detectar hemoglobina humana con un punto de corte de 100 ng/ml (prueba positiva). Se realizó colonoscopia a los positivos. Se tomaron biopsias dirigidas de las lesiones premalignas/cáncer para análisis histopatológico. RESULTADOS: Se procesaron 751 FIT, de las cuales 51 (6.8%) fueron positivas, con una tasa de 15.9 lesiones premalignas por cada 1,000 sujetos evaluados, y 1.3 pacientes con CCR por cada 1,000 pacientes. CONCLUSIONES: Nuestro estudio concuerda con lo reportado en la literatura mundial, apoyando así la iniciativa de fomentar el establecimiento de un tamizaje formal y estandarizado dentro del sector de salud pública.

Experimental model standardizing polyvinyl alcohol hydrogel to simulate endoscopic ultrasound and endoscopic ultrasound-elastography.

BACKGROUND: Endoscopic ultrasound (EUS) and endoscopic ultrasound elastography (EUS-E) simulation lessens the learning curve; however, models lack realism, diminishing competitiveness. AIM: To standardize the mechanical properties of polyvinyl alcohol (PVA) hydrogel for simulating organs and digestive lesions. METHODS: PVA hydrogel (Sigma Aldrich, degree of hydrolysis 99%) for simulating EUS/EUS-E lesions was investigated in Unidad de Investigación y Desarrollo Tecnológico at Hospital General de México "Dr. Eduardo Liceaga", Mexico City. We evaluated physical, contrast, elasticity and deformation coefficient characteristics in lesions, applying Kappa's concordance and satisfaction questionnaire (Likert 4-points). RESULTS: PVA hydrogel showed stable mechanical properties. Density depended on molecular weight (MW) and concentration (C). PVA bblocks with the greatest density showed lowest tensile strength (r = -0.8, P = 0.01). Lesions were EUS-graphically visible. Homogeneous and heterogeneous examples were created from PVA blocks or PVA phantoms, exceeding (MW2 = 146000-186000, C9 = 15% and C10 = 20%) with a density under (MW1 = 85000-124000, C1 = 7% and C2 = 9%). We calculated elasticity and deformation parameters of solid (blue) areas, contrasting with the norm (Kappa = 0.8; high degree of satisfaction). CONCLUSION: PVA hydrogels were appropriate for simulating organs and digestive lesions using EUS/EUS-E, facilitating practice and reducing risk. Repetition amplified skills, while reducing the learning curve.

Acute dysphagia presentation and its association with esophagitis dissecans and concomitant diseases. A diagnostic challenge.

Esophagitis dissecans (ESD) is an uncommon disease that is associated with eosinophilic esophagitis (EoE), candidiasis and/or drugs. We aim to characterize the clinical, endoscopic and histological damage of the mucosal in subjects with dysphagia, its relation to concomitant entities and the treatment response. This is a retrospective observational study in patients with dysphagia and esophageal mucosal damage We included 23 patients (mean age = 55 years) who had GERD symptoms, dysphagia and/or odynophagia. There were 10, 9 and 4 cases of esophagitis dissecans, desquamative/esfacelante (ESD/ES) and fibrostenotic, respectively. ESD/SE is a rare entity with variable clinical, endoscopic and histological spectrum. The association with GERD was frequent.

La esofagitis disecante (ESD) es una enfermedad rara que puede asociarse a esofagitis eosinofílica, candidiásica o medicamentos. Se analizaron las características clinico-endoscópicas e histopatológicas en sujetos con disfagia de corta evolución asociada a afecciones concurrentes. Estudio observacional de cohorte retrospectiva con disfagia y daño mucoso. Se ingresaron 23 pacientes con edad media de 55 años. Todos tuvieron síntomas de reflujo gastroesofágico (ERGE), disfagia y odinofagia. Fueron 10, 9 y 4 casos de ESD, descamativa/esfacelante (ESD/ES) y fibroestenosis, respectivamente. La ESD/SE es una afección rara, con un espectro clínico, endoscópico e histológico variable.

Proton pump inhibitors in gastroesophageal reflux disease: "a custom-tailored therapeutic regimen".

The Montreal Definition and Classification divides Gastroesophageal Reflux Disease (GERD) into esophageal symptomatic syndromes (and with mucosal damage) and extraesophageal syndromes (with acid established association and proposed association). In typical GERD symptoms, an 8-week treatment with PPIs is satisfactory in most cases (> 90%). Response rates to PPIs in GERD are highly variable, as they also rely on an appropriate clinical diagnosis of the disease; endoscopy differentiates the macroscopic GERD phenotype. The non-erosive variety (50-70% prevalence) has a different symptomatic response rate, as gastric acid is not the sole etiology of symptoms. The possible explanations of treatment failure include treatment adherence, PPI metabolism alterations and characteristics, and inadequate diagnosis. Refractory symptoms are related to gastric content neutralization by the chronic use of PPIs.Extraesophageal manifestations are associated with other pathophysiological mechanisms where an autonomic nervous system disturbance gives rise to symptoms. In these clinical entities, the relationship between symptoms and acid needs to be established in order to determine the use of PPIs, or consider other drugs. In other words, so as to "custom-tailor the best-fitting therapy" we need to answer the questions for whom, for what, how and for how long. Finally, PPI safety and tolerability are factors to be considered in elderly patients requiring chronic PPI use, who usually have chronic concomitant illnesses.

"Diseñando un traje a la medida": los inhibidores de la bomba de protones en la enfermedad por reflujo gastroesofágico / Proton pump inhibitors in gastroesophageal reflux disease: "a custom-tailored therapeutic regimen"

La Clasificación de Montreal divide la enfermedad por reflujo gastro-esofágico (ERGE) en síndromes esofágicos sintomáticos y con daño a la mucosa y en síndromes extraesofágicos con asociación establecida al ácido y asociación propuesta. En síntomas ERGE típicos el tratamiento con inhibidores de la bomba de protones (IBP) es satisfactorio (> 90%) a 8 semanas en la mayoría de los casos. Las tasas de respuesta a los IBP en la ERGE son muy variables; ya que también dependen de un adecuado diagnóstico clínico de la enfermedad; la endoscopia diferencia el fenotipo macroscópico de la ERGE. La variedad no erosiva (prevalencia 50-70%) tiene una tasa de respuesta sintomática diferente ya que el ácido no es causa suficiente para explicar los síntomas. Las posibles explicaciones a la falla al tratamiento son el apego al tratamiento, alteraciones en el metabolismo y características de IBP y diagnóstico inadecuado. Los síntomas refractarios se relacionan con neutralización del contenido por el uso crónico de IBP. Las manifestaciones extraesofágicas se asocian con otros mecanismos fisiopatológicos como la disfunción del sistema nervioso autónomo. En estas entidades es necesario establecer la relación o no con el ácido para determinar el uso con IBP o considerar otros fármacos. Es decir, necesitamos responder a las preguntas en quien, para qué, cómo y por cuánto tiempo, para diseñar un "traje a la medida". Por último, la seguridad y la tolerabilidad a IBP son factores a considerar en pacientes de edad avanzada que requieren su uso crónico y que generalmente tienen enfermedades crónicas concomitantes (AU)

The Montreal Definition and Classification divides Gastroesophageal Reflux Disease (GERD) into esophageal symptomatic syndromes (and with mucosal damage) and extraesophageal syndromes (with acid established association and proposed association). In typical GERD symptoms, an 8-week treatment with PPIs is satisfactory in most cases (> 90%). Response rates to PPIs in GERD are highly variable, as they also rely on an appropriate clinical diagnosis of the disease; endoscopy differentiates the macroscopic GERD phenotype. The non-erosive variety (50-70% prevalence) has a different symptomatic response rate, as gastric acid is not the sole etiology of symptoms. The possible explanations of treatment failure include treatment adherence, PPI metabolism alterations and characteristics, and inadequate diagnosis. Refractory symptoms are related to gastric content neutralization by the chronic use of PPIs. Extraesophageal manifestations are associated with other pathophysiological mechanisms where an autonomic nervous system disturbance gives rise to symptoms. In these clinical entities, the relationship between symptoms and acid needs to be established in order to determine the use of PPIs, or consider other drugs. In other words, so as to "custom-tailor the best-fitting therapy" we need to answer the questions for whom, for what, how and for how long. Finally, PPI safety and tolerability are factors to be considered in elderly patients requiring chronic PPI use, who usually have chronic concomitant illnesses (AU)