Anatomía quirúrgica para hernioplastias inguinales transabdominales preperitoneales (TAPP) (video)

Introducción  El abordaje laparoscópico para hernioplastias inguinales requiere un conocimiento exhaustivo de la anatomía posterior de la región, distinto al utilizado para los procedimientos por vía anterior. Esto supone un desafío para los cirujanos.  Descripción de contenidos  En el video se presenta la correlación entre el modelo cadavérico y el procedimiento laparoscópico de la hernioplastia transabdominal preperitoneal (TAPP), identificando las estructuras que permiten la realización de un procedimiento seguro. Se presenta el concepto de  visión crítica de seguridad del orificio miopectíneo de Fruchaud y la técnica utilizada en nuestro servicio.  Observaciones y comentarios  La reparación laparoscópica de las hernias inguinales es técnicamente más demandante que el procedimiento de Lichtenstein (hasta ahora gold standard) con una curva de aprendizaje más larga y mayor número de complicaciones. Por lo tanto resulta fundamental la utilización de recursos a que favorezcan la familiarización con la anatomía y técnica quirúrgica, entre ellos el material cadavérico

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

CONDUCTO BILIAR SUBVESICULAR: HALLAZGO QUIRÚRGICO Y COLANGIOGRÁFICO. Sub-gallbladder bile duct: Surgical and colangiographic findings

Las variaciones de la vía biliar son frecuentes y pueden provocar complicaciones en el curso de una colecistectomía. Por esta razón el cirujano debe estar interiorizado en la anatomía habitual así como en las posibles variantes. Presentamos un caso de un conducto biliar subvesicular encontrando durante una colecistectomía. Se trató de un conducto que se originaba en el conducto hepático derecho y terminaba en la vesícula biliar. Se procedió a la ligadura del mismo y su posterior sección. El paciente tuvo una buena evolución y fue dado de alta a las 48 horas del posoperatorio. En vistas a este hallazgo se discuten la anatomía y las implicancias quirúrgicas de esta variante. Variations in the biliary tract are frequent and may cause complications during a cholecyst-ectomy. Thus, the surgeon must have a deep knowledge of the usual configuration of the biliary tract as well as its variations. We report a case of a subvesical bile duct found during a cholec-ystectomy. It consisted of a bile duct which originated from the right hepatic duct and ended in the gallbladder. The duct was clipped and cut, the patient had good evolution and was discharged 48 hours after surgery. The anatomy and surgical implications of this variation are discussed

Cirugía del Control de Daños. Fundamentos y Resultados. Revisión de 4 años en un hospital público de Uruguay

El trauma es la pandemia del nuevo milenio y la tercera causa de muerte en Uruguay siendo la principal causa de muerte en menores de 40 años. La cirugía de control de daños surge con el afán de mejorar los pobres resultados obtenidos con los abordajes quirúrgicos tradicionales en traumatismos abdominales exanguinantes. Esta nueva estrategia ha demostrado obtener mejoras de la sobrevida. Realizamos un estudio descriptivo, retrospectivo, observacional, tipo serie de casos en el Hospital Maciel, Montevideo, Uruguay, mediante revisión de historias clínicas, descripciones operatorias y datos de internación en Centro de Cuidados Intensivos de todos los pacientes traumatizados o heridos a los cuales se realizó cirugía de control de daños abdominal desde el marzo de 2010 a julio 2014. Obtuvimos datos de 15 pacientes en los que se indicó cirugía de control de daños: 12 hombres (80%), y 3 mujeres (20%). La media de edad de presentación fue de 30,2 años. Todos presentaban inestabilidad hemodinámica al llegar a emergencia y fueron politransfundidos durante la cirugía. El cierre parietal se logró en 11 pacientes. El promedio de días en laparostomía fue de 12,6 días. La mortalidad global de la serie fue de 46,66%. La principal causa de muerte fue shock refractario y disfunción orgánica múltiple mantenido mientras que en 2 pacientes en los cuales se logró el cierre parietal, la mortalidad se debió a traumatismo encéfalo craneano grave asociado y sepsis mantenida por falla de sutura

DRENAJE QUIRÚRGICO EXTRAPERITONEAL DE ABSCESO DEL PSOAS: FUNDAMENTO ANATÓMICO. Drenaje quirúrgico extraperitoneal de absceso del psoas: Fundamento anatómico

El espacio extraperitoneal se encuentra delimitado por el peritoneo parietal y las paredes de la cavidad abdómino-pélvica. Al igual que la cavidad peritoneal este espacio puede ser asiento de diversas colecciones, como ser hematomas, tumores y supuración. Con el advenimiento de las nuevas técnicas de imagen, se ha contribuido no solo al mejor diagnóstico de estas patologías sino también a su mejor manejo. El objetivo de este trabajo es mostrar la anatomía del abordaje extraperitoneal del comparti-miento del psoas y su aplicación al tratamiento de un paciente. Para esto se utilizaron 5 cadáveres adultos fijados previamente en solución en base a formol. Se realizó disección bilateral de la pared antero-lateral del abdomen reclinando la bolsa peritoneal para a continuación abordar el compartimiento del músculo psoas. Este conocimiento fue utilizado en el tratamiento quirúrgico de una paciente que consultó por un absceso del compartimiento del psoas derecho. En las preparaciones cadavéricas, se observó cómo al rebatir el peritoneo parietal se expone la totalidad del compartimiento muscular del psoas. Este procedi-miento fue realizado a la paciente consiguiendo el drenaje completo de la cavidad abscedada, quien tuvo una buena evolución y fue dada de alta a los 7 días. Los hallazgos demuestran una vez más como el conocimiento anatómico sigue estando vigente en la práctica clínica, siendo la comprensión del espacio extraperitoneal fundamental no solo para el anatomista sino también para el cirujano.  The retroperitoneal space is bounded by the parietal peritoneum and the posterior abdominal wall. Just like the peritoneal cavity, this region can host multiple effusions such as hematomas, tumors and suppuration. With the development of new radiological technics, both diagnosis and management of these conditions has improved. The purpose of this paper is to demonstrate the anatomy of the extraperitoneal approach of the psoas compartment and its application to a patient´s surgical treatment. For this purpose 5 formalin-fixed adult cadavers were used. Bilateral dissection of the antero-lateral abdominal wall was performed in every specimen. Once the parietal peritoneum was mobilized the psoas compartment was approached. This knowledge was used during the surgical treatment of a patient who attended to the emergency room with a right psoas compartment abscess. In the cadaveric specimens, the psoas muscular compartment was approached after mobilizing the parietal peritoneum medially. This procedure was carried out in the patient resulting in complete drainage of the purulent effusion. The patient had complete relief of the symptoms and was discharged 7 days after the procedure. These findings show that the anatomic knowledge is still important in clinical practice. Understanding the extraperitoneal space is crucial for both anatomists and surgeons. </jats:p

DRENAJE QUIRÚRGICO EXTRAPERITONEAL DE ABSCESO DEL PSOAS: FUNDAMENTO ANATÓMICO. Drenaje quirúrgico extraperitoneal de absceso del psoas: Fundamento anatómico

El espacio extraperitoneal se encuentra delimitado por el peritoneo parietal y las paredes de la cavidad abdómino-pélvica. Al igual que la cavidad peritoneal este espacio puede ser asiento de diversas colecciones, como ser hematomas, tumores y supuración. Con el advenimiento de las nuevas técnicas de imagen, se ha contribuido no solo al mejor diagnóstico de estas patologías sino también a su mejor manejo. El objetivo de este trabajo es mostrar la anatomía del abordaje extraperitoneal del comparti-miento del psoas y su aplicación al tratamiento de un paciente. Para esto se utilizaron 5 cadáveres adultos fijados previamente en solución en base a formol. Se realizó disección bilateral de la pared antero-lateral del abdomen reclinando la bolsa peritoneal para a continuación abordar el compartimiento del músculo psoas. Este conocimiento fue utilizado en el tratamiento quirúrgico de una paciente que consultó por un absceso del compartimiento del psoas derecho. En las preparaciones cadavéricas, se observó cómo al rebatir el peritoneo parietal se expone la totalidad del compartimiento muscular del psoas. Este procedi-miento fue realizado a la paciente consiguiendo el drenaje completo de la cavidad abscedada, quien tuvo una buena evolución y fue dada de alta a los 7 días. Los hallazgos demuestran una vez más como el conocimiento anatómico sigue estando vigente en la práctica clínica, siendo la comprensión del espacio extraperitoneal fundamental no solo para el anatomista sino también para el cirujano.  The retroperitoneal space is bounded by the parietal peritoneum and the posterior abdominal wall. Just like the peritoneal cavity, this region can host multiple effusions such as hematomas, tumors and suppuration. With the development of new radiological technics, both diagnosis and management of these conditions has improved. The purpose of this paper is to demonstrate the anatomy of the extraperitoneal approach of the psoas compartment and its application to a patient´s surgical treatment. For this purpose 5 formalin-fixed adult cadavers were used. Bilateral dissection of the antero-lateral abdominal wall was performed in every specimen. Once the parietal peritoneum was mobilized the psoas compartment was approached. This knowledge was used during the surgical treatment of a patient who attended to the emergency room with a right psoas compartment abscess. In the cadaveric specimens, the psoas muscular compartment was approached after mobilizing the parietal peritoneum medially. This procedure was carried out in the patient resulting in complete drainage of the purulent effusion. The patient had complete relief of the symptoms and was discharged 7 days after the procedure. These findings show that the anatomic knowledge is still important in clinical practice. Understanding the extraperitoneal space is crucial for both anatomists and surgeons.

Multiscale modeling of ultrafast melting phenomena

AbstractUltraviolet Nanosecond Laser Annealing (LA) is a powerful tool for both fundamental investigations of ultrafast, nonequilibrium phase-change phenomena and technological applications (e.g., the processing of 3D sequentially integrated nano-electronic devices) where strongly confined heating and melting is desirable. Optimizing the LA process along with the experimental design is challenging, especially when involving complex 3D-nanostructured systems with various shapes and phases. To this purpose, it is essential to model critical nanoscale physical LA-induced phenomena, such as shape changes or formation and evolution of point and extended defects. To date, LA simulators are based on continuum models, which cannot fully capture the microscopic kinetics of a solid–liquid interface. In this work a fully atomistic LA simulation methodology is presented, based on the parallel coupling of a continuum, finite elements, μm-scale electromagnetic-thermal solver with a super-lattice Kinetic Monte Carlo atomistic model for melting. Benchmarks against phase-field models and experimental data validate the approach. LA of a Si(001) surface is studied varying laser fluence and pulse shape, assuming both homogeneous and inhomogeneous nucleation, revealing how liquid Si nuclei generate, deform and coalesce during irradiation. The proposed methodology is applicable to any system where the atom kinetics is determined by a strongly space- and time-dependent field, such as temperature or strain.</jats:p

Multiscale modeling of ultrafast melting phenomena

Ultraviolet Nanosecond Laser Annealing (LA) is a powerful tool for both fundamental investigations of ultrafast, nonequilibrium phase-change phenomena and technological applications (e.g., the processing of 3D sequentially integrated nano-electronic devices) where strongly confined heating and melting is desirable. Optimizing the LA process along with the experimental design is challenging, especially when involving complex 3D-nanostructured systems with various shapes and phases. To this purpose, it is essential to model critical nanoscale physical LA-induced phenomena, such as shape changes or formation and evolution of point and extended defects. To date, LA simulators are based on continuum models, which cannot fully capture the microscopic kinetics of a solid-liquid interface. In this work a fully atomistic LA simulation methodology is presented, based on the parallel coupling of a continuum, finite elements, μm-scale electromagnetic-thermal solver with a super-lattice Kinetic Monte Carlo atomistic model for melting. Benchmarks against phase-field models and experimental data validate the approach. LA of a Si(001) surface is studied varying laser fluence and pulse shape, assuming both homogeneous and inhomogeneous nucleation, revealing how liquid Si nuclei generate, deform and coalesce during irradiation. The proposed methodology is applicable to any system where the atom kinetics is determined by a strongly space-and time-dependent field, such as temperature or strain

GANDALF: Generative ANsatz for DNA damage evALuation and Forecast. A neural network-based regression for estimating early DNA damage across micro-nano scales

International audiencePurpose: This study aims to develop a comprehensive simulation framework to connect radiation effects from the microscopic to the nanoscopic scale.Method: The process begins with a Geant4-DNA simulation based on the example ”molecularDNA”, producing a dataset of twelve different types of early DNA damages within an Escherichia coli (E. coli) bacterium, generated by proton irradiation at different kinetic energies, giving a nano-scale view of the particle–matter interaction. Then we pass to the micro-scale with a Geant4 simulation, based on the example ”radiobiology”, providing a microscopic view of proton interactions with matter through the Linear Energy Transfer (LET). Then GANDALF (Generative ANsatz for DNA damage evALuation and Forecast) Machine Learning (ML) toolkit, a Neural Network (NN)-based regression system, is employed to correlate the micro-scale LET data with the nano-scale occurrences of DNA damages in the E. coli bacterium.Results: The trained ML algorithm provides a practical tool to convert LET curves versus depth in a water phantom into DNA damage curves for twelve distinct types of DNA damage. To assess the performance, we evaluated the choice and optimization of the regression system based on its interpolation and extrapolation capabilities, ensuring the model could reliably predict DNA damage under various conditions.Conclusions: Through the synergistic integration of Geant4, Geant4-DNA and ML, the study provides a tool to easily convert the results at the micro-scale of Geant4 to those at the nano-scale of Geant4-DNA without having to deal with the high CPU time requirements of the latter

Results of a Geant4 benchmarking study for bio‐medical applications, performed with the G4‐Med system

International audienceBackgroundGeant4, a Monte Carlo Simulation Toolkit extensively used in bio‐medical physics, is in continuous evolution to include newest research findings to improve its accuracy and to respond to the evolving needs of a very diverse user community. In 2014, the G4‐Med benchmarking system was born from the effort of the Geant4 Medical Simulation Benchmarking Group, to benchmark and monitor the evolution of Geant4 for medical physics applications. The G4‐Med system was first described in our Medical Physics Special Report published in 2021. Results of the tests were reported for Geant4 10.5. PurposeIn this work, we describe the evolution of the G4‐Med benchmarking system.Methods The G4‐Med benchmarking suite currently includes 23 tests, which benchmark Geant4 from the calculation of basic physical quantities to the simulation of more clinically relevant set‐ups. New tests concern the benchmarking of Geant4‐DNA physics and chemistry components for regression testing purposes, dosimetry for brachytherapy with a source, dosimetry for external x‐ray and electron FLASH radiotherapy, experimental microdosimetry for proton therapy, and in vivo PET for carbon and oxygen beams. Regression testing has been performed between Geant4 10.5 and 11.1. Finally, a simple Geant4 simulation has been developed and used to compare Geant4 EM physics constructors and physics lists in terms of execution times. ResultsIn summary, our EM tests show that the parameters of the multiple scattering in the Geant4 EM constructor G4EmStandardPhysics_option3 in Geant4 11.1, while improving the modeling of the electron backscattering in high atomic number targets, are not adequate for dosimetry for clinical x‐ray and electron beams. Therefore, these parameters have been reverted back to those of Geant4 10.5 in Geant4 11.2.1. The x‐ray radiotherapy test shows significant differences in the modeling of the bremsstrahlung process, especially between G4EmPenelopePhysics and the other constructors under study ( G4EmLivermorePhysics , G4EmStandardPhysics_option3 , and G4EmStandardPhysics_option4 ). These differences will be studied in an in‐depth investigation within our Group. Improvement in Geant4 11.1 has been observed for the modeling of the proton and carbon ion Bragg peak with energies of clinical interest, thanks to the adoption of ICRU90 to calculate the low energy proton stopping powers in water and of the Linhard–Sorensen ion model, available in Geant4 since version 11.0. Nuclear fragmentation tests of interest for carbon ion therapy show differences between Geant4 10.5 and 11.1 in terms of fragment yields. In particular, a higher production of boron fragments is observed with Geant4 11.1, leading to a better agreement with reference data for this fragment.ConclusionsBased on the overall results of our tests, we recommend to use G4EmStandardPhysics_option4 as EM constructor and QGSP_BIC_HP with G4EmStandardPhysics_option4 , for hadrontherapy applications. The Geant4‐DNA physics lists report differences in modeling electron interactions in water, however, the tests have a pure regression testing purpose so no recommendation can be formulated