Dermolipectomía por lipodistrofia abdominal grave en obesidad mórbida / Dermolipectomy for severe abdominal lipodystrophy in morbid obesity

RESUMEN La obesidad y el sobrepeso se definen como una acumulación anormal o excesiva de grasa que puede ser perjudicial para la salud. Es una enfermedad crónica de origen multifactorial, que como consecuencia ocasiona problemas higiénicos, discapacidad funcional y alteración de la calidad de vida. La dermolipectomía abdominal es una técnica quirúrgica que constituye la única opción para el tratamiento de pacientes con panículo adiposo prominente; de esa forma se logra disminuir las complicaciones y se reintegra socialmente al paciente que, a causa del enorme faldón abdominal, estuvo limitado por muchos años. Presentamos el caso de una paciente de 53 años con lipodistrofia abdominal grave, que llegaba a ambos tobillos con afectación cutánea, y discapacidad para realizar actividades diarias, resuelta con dermolipectomía abdominal y resección de 29 kg de tejido dermograso. Se realizará, además, una revisión bibliográfica del tema.

ABSTRACT Overweight and obesity are defined as abnormal or excessive fat accumulation that presents a risk to health. It is a chronic disease caused by multiple factors, which results in hygienic issues, functional disability and impaired quality of life. Abdominal dermolipectomy is the only surgical option for the treatment of patients with prominent panniculus morbidus, thus reducing complications and providing social reintegration for the patient who has been limited for many years due to the enormous abdominal panniculus. We report the case of a 53-year-old female patient with severe abdominal lipodystrophy with coverage of both ankles, skin involvement, and disability to perform daily activities, that was managed with abdominal dermolipectomy and resection of 29 kg of dermo-adipose tissue. Bibliographic research is also presented.

Estudio complementario de la patología biliar complicada y el manejo de la litiasis coledociana en dos tiempos / Complementary evaluation of complicated gallstone disease and two-stage management of choledochal lithiasis

RESUMEN Antecedentes: la litiasis biliar tiene una prevalencia actual en Occidente del 10-20%. El 7-16% de los pacientes presentan también coledocolitiasis. El diagnóstico preoperatorio de coledocolitiasis es difícil de establecer. Objetivo: establecer nuestra experiencia en el estudio de la patología biliar complicada y el manejo de la coledocolitiasis en dos tiempos, como terapéutica de elección. Material y métodos: estudio prospectivo, observacional. Pacientes con patología biliar sometidos a procedimientos en el Servicio de Cirugía General del Hospital Vidal, desde el 30/06/2019 al 30/12/2019. Resultados: la ecografía hepato-bilio-pancreática (HPB) es específica, con exactitud del 80,9% y sensibilidad del 50%. La colangio resonancia magnética (CRNM) es 100% específica, tiene exactitud del 84,6% y sensibilidad de 67%. La colangio pancreatografía retrógrada endoscópica (ERCP -por sus siglas en inglés-), durante la primera colangiografía mostró en el 100% litiasis coledociana, pero, luego del tratamiento, la colangiografía de "control" muestra 0% de sensibilidad, 100% especificidad, con exactitud del 15,4%. En los hallazgos intraoperatorios, el cístico dilatado en asociación con alteraciones humorales ha demostrado una sensibilidad del 100%, especificidad del 90% y tasa de exactitud de 93,6%. Conclusión: la colangiografía intraoperatoria (CIO) es el procedimiento de referencia ("gold standard") en el abordaje de la patología biliar complicada, siendo su uso sistemático. La asociación entre alteraciones de parámetros humorales y el cístico dilatado resulta un parámetro con alto valor predictivo para la presencia de litiasis coledociana.

ABSTRACT Background: Nowadays, the prevalence of gallstones ranges between 10 and 20% in Western world, and 7-16% of the patients also present choledocholithiasis. The preoperative diagnosis of choledocholithiasis is difficult. Objective: To establish our experience in the evaluation of complicated gallstone disease and two-stage management of choledochal lithiasis as standard or care. Material and methods: This prospective and observational study included patients hospitalized with gallstone disease undergoing procedures in the Department of General Surgery of Hospital Vidal from June 30, 2019, to December 30, 2019. Results: Ultrasound of the liver, biliary tract and pancreas was specific, with accuracy of 80.9% and sensitivity of 50%. Magnetic resonance cholangiopancreatography (MRCP) had a sensitivity of 100%, accuracy of 84.6% and sensitivity of 67%. As for endoscopic retrograde cholangiopancreatography (ERCP), the diagnosis of choledocholithiasis was made in 100% of the cases during the first cholangiography while "control" cholangiography had a sensitivity of 0%, specificity of 100% and accuracy of 15.4%. The presence of a dilated cystic duct intraoperatively in association with abnormal biochemical parameters had a sensitivity of 100%, specificity of 90%, and accuracy of 93.6%. Conclusion: Intraoperative cholangiography (IOC) is the gold standard procedure for the management of complicated gallstone disease. The association of biochemical parameters and a dilated cystic duct has high predictive value for choledochal lithiasis.

Lesión quirúrgica de la vía biliar: experiencia en el Hospital José Ramón Vidal de Corrientes / Bile duct injury after cholecystectomy: the experience of Hospital José Ramón Vidal de Corrientes

RESUMEN Antecedentes: la lesión quirúrgica de la vía biliar representa un gran problema de salud y puede surgir ante cualquier cirujano que realice una colecistectomía. Objetivos: el objetivo del trabajo fue presentar nuestra experiencia en reparación de la vía biliar, ana lizando la morbimortalidad y la incidencia de dicha patología en nuestro Servicio. Material y métodos: estudio retrospectivo descriptivo; se tomaron las variables de las historias clínicas de los pacientes en un período de 8 años, de enero de 2011 a julio de 2019 donde fueron admitidos 19 pacientes que presentaron lesión quirúrgica de la vía biliar en el Hospital José Ramón Vidal de la provincia de Corrientes, Argentina. Resultados: 12 pacientes fueron tratados quirúrgicamente mediante hepático-yeyuno anastomosis, 2 por bihepático-yeyuno anastomosis y dos mediante sutura término-terminal bilio-biliar sobre tubo de Kehr. Tres pacientes fueron tratados mediante colocación de stent y dilatación posterior mediante colangiopancreatografia retrógrada endoscópica. Conclusión: los cirujanos deben entrenarse para disminuir al mínimo la posibilidad de una lesión. El objetivo de una colecistectomía debería ser no lesionar la vía biliar.

ABSTRACT Background: Bile duct injury represents a serious health problem and can occur after any cholecystectomy. Objectives: The aim of this study was to report our experience in repairing bile duct injuries analyzing morbidity, mortality and its incidence in our department. Material and Methods: We conducted a retrospective and descriptive study. The information was retrieved form the medical records of 19 patients with bile duct injury hospitalized at the Hospital José Ramón Vidal, Corrientes, Argentina, between January 2011 and July 2019. Results: A Roux-en-Y hepaticojejunostomy was performed in 12 patients, double hepaticojejunostomy in two patients, and two patients were treated with end-to-end ductal anastomosis with suture over a T tube. Three patients underwent endoscopic retrograde cholangiopancreatography with stent placement and dilation. Conclusion: Surgeons should be trained to avoid the possibility of bile duct injury. The main goal of cholecystectomy should be to avoid this complication.

Slender-body theory for plasmonic resonance.

We develop a slender-body theory for plasmonic resonance of slender metallic nanoparticles, focusing on a general class of axisymmetric geometries with locally paraboloidal tips. We adopt a modal approach where one first solves the plasmonic eigenvalue problem, a geometric spectral problem which governs the surface-plasmon modes of the particle; then, the latter modes are used, in conjunction with spectral-decomposition, to analyse localized-surface-plasmon resonance in the quasi-static limit. We show that the permittivity eigenvalues of the axisymmetric modes are strongly singular in the slenderness parameter, implying widely tunable, high-quality-factor, resonances in the near-infrared regime. For that family of modes, we use matched asymptotics to derive an effective eigenvalue problem, a singular non-local Sturm-Liouville problem, where the lumped one-dimensional eigenfunctions represent axial voltage profiles (or charge line densities). We solve the effective eigenvalue problem in closed form for a prolate spheroid and numerically, by expanding the eigenfunctions in Legendre polynomials, for arbitrarily shaped particles. We apply the theory to plane-wave illumination in order to elucidate the excitation of multiple resonances in the case of non-spheroidal particles.

Mathematical and numerical framework for metasurfaces using thin layers of periodically distributed plasmonic nanoparticles.

In this paper, we derive an impedance boundary condition to approximate the optical scattering effect of an array of plasmonic nanoparticles mounted on a perfectly conducting plate. We show that at some resonant frequencies the impedance blows up, allowing for a significant reduction of the scattering from the plate. Using the spectral properties of a Neumann-Poincaré type operator, we investigate the dependency of the impedance with respect to changes in the nanoparticle geometry and configuration.