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Antecedentes: La esterilización tubárica se realiza en un número importante de pacientes jóvenes que por diferentes motivos desean posteriormente un nuevo embarazo, porcentaje que varía entre el 1,3-15%. Hasta ahora la cirugía ha sido la primera alternativa de tratamiento y gracias a la evolución de la técnica y el desarrollo de material quirúrgico, es posible de realizar por vía laparoscópica. Objetivos: Hacer una síntesis de la historia y técnicas utilizadas en la reanastomosis tubárica, los criterios de selección, el estudio preoperatorio, los factores pronósticos y comparar los resultados de la laparotomía y la laparoscopia. Métodos: Se realiza búsqueda en base de datos Medline PubMed usando las palabras clave: tubal anastomosis, reversal of esterilization, infertility, microsurgery, tubal esterilization; se seleccionan todas aquellas publicaciones tipo review de reanastomosis tubárica con microcirugía abierta y todas aquellas de reanastomosis por vía laparoscópica. Resultados: La reanastomosis tubárica por laparotomía con técnica microquirúrgica tiene un éxito entre 60 y 90% de tasas de embarazo. Las primeras publicaciones de la técnica laparoscópica no presentan resultados satisfactorios, sin embargo casuísticas más numerosas y especialmente las que muestran la técnica microlaparoscópica tienen resultados similares con todas las ventajas de la laparoscopia. Conclusión: La recanalización tubaria por vía laparoscopica es una técnica factible, probada y exitosa, alternativa a la laparotomía, sin embargo, para su implementación con resultados satisfactorios es necesario contar con equipamiento apropiado, experiencia previa en cirugía abierta y entrenamiento en cirugía endoscópicaBackground: Tubal ligation is used in a large number of young patients, who frequently want a new pregnancy, the percentage rate ranges from 1.3 to 15%. Until now the standard treatment has been the microsurgical tubal anastomosis through laparotomy, however, the development of new techniques and instruments allowed a laparoscopic approach for this surgery. Objectives: to make a synthesis of the hystory and operatory technics in laparoscopic tubal anastomosis to evaluate the inclusions criteria, the preoperative work-up, the factors of prognosis and to make a comparison between laparotomy and laparoscopy. Methods: We make a search in medline database (PubMed), with the key words: tubal anastomosis, reversal of sterilization, infertility, microsurgery, tubal sterilization, and selecting all of the review publications in microsurgical tubal reanastomosis by laparotomy and all of publications of the laparoscopic technic. Results: The microsurgical tubal anastomosis through laparotomy has a pregnancy rate ranging from 70% to 80%. The first publications whith the laparoscopic technic show dissapointed results, however, papers with bigger casuistics and with the microlaparoscopic technic show the same results that the open technic with all of the advantages of the laparoscopy. Conclusion: Laparoscopic tubal reversal is a feasible, tested and successful alternative to the traditional surgery performed by laparotomy, however, to achieve a successful outcome it is necessary a meticulous surgical technique, adequate equipment and extensive experience with tubal anastomosis by laparotomy and advances laparoscopic techniques

We investigate the electrical asymmetry effect (EAE) and the current dynamics in a geometrically asymmetric capacitively coupled radio frequency plasma driven by multiple consecutive harmonics based on a nonlinear global model. The discharge symmetry is controlled via the EAE, i.e., by varying the total number of harmonics and tuning the phase shifts ( θ k ) between them. Here, we systematically study the EAE in a low pressure (4 Pa) argon discharge with different geometrical asymmetries driven by a multifrequency rf source consisting of 13.56 MHz and its harmonics. We find that the geometrical asymmetry strongly affects the absolute value of the DC self-bias voltage, but its functional dependence on θ k is similar at different values of the geometrical asymmetry. Also, the values of the DC self-bias are enhanced by adding more consecutive harmonics. The voltage drop across the sheath at the powered and grounded electrode is found to increase/decrease, respectively, with the increase in the number of harmonics of the fundamental frequency. For the purpose of validating the model, its outputs are compared with the results obtained in a geometrically and electrically asymmetric 2f capacitively coupled plasmas experiment conducted by Schuengel et al. [J. Appl. Phys. 112, 053302 (2012)]. Finally, we study the self-excitation of nonlinear plasma series resonance oscillations and its dependence on the geometrical asymmetry as well as the phase angles between the driving frequencies. [ABSTRACT FROM AUTHOR]