Prótesis colónicas en el tratamiento paliativo del cáncer colónico. Nuestra evaluación tras 10 años de experiencia / Self-expanding metal stents in the palliative treatmentof coloncancer. Results of 10 years of experience

Introducción: la colocación de prótesis metálicas autoexpansibles (PAE) por vía endoscópica surge como opción terapéutica para la obstrucción colónica neoplásica en dos situaciones: como tratamiento paliativo y como puente a la cirugía curativa. Este procedimiento evita cirugías en dos tiempos y disminuye la probabilidad de colostomía definitiva y sus complicaciones con el consecuente deterioro de la calidad de vida. Objetivo: comunicar nuestra experiencia en la colocación de PAE para el tratamiento paliativo de la obstrucción colorrectal neoplásica. Diseño: retrospectivo, longitudinal, descriptivo y observacional. Material y métodos: se incluyeron todos los pacientes a quienes el mismo grupo de endoscopistas les colocó PAE con intención paliativa por cáncer colorrectal avanzado entre agosto de 2008 y diciembre de 2019. Fueron analizadas las variables demográficas y clínicas, el éxito técnico y clínico, las complicaciones tempranas y tardías y la supervivencia. Resultados: se colocó PAE en 54 pacientes. La media de edad fue 71 años. El 85% de las lesiones se localizó en el colon izquierdo. En el 57% de los pacientes se realizó en forma ambulatoria. El éxito técnico y clínico fue del 92 y 90%, respectivamente y la supervivencia media de 209 días. La tasa de complicaciones fue del 29,6%, incluyendo un 14,8% de obstrucción y un 5,6% de migración. La mortalidad tardía atribuible al procedimiento fue del 5,6%, ocasionada por 3 perforaciones tardías: 2 abiertas y 1 microperforación con formación de absceso localizado. Conclusiones: la colocación de PAE como tratamiento paliativo de la obstrucción neoplásica colónica es factible, eficaz y segura. Permitió el manejo ambulatorio o con internación breve y la realimentación temprana, mejorando las condiciones para afrontar un eventual tratamiento quimioterápico paliativo. Las mayoría de las complicaciones fueron tardías y resueltas endoscópicamente en forma ambulatoria. (AU)

Introduction: endoscopic placement of self-expanding metal stents (SEMS) emerges as a therapeutic option for neoplastic obstruction of the colon in two situations: as palliative treatment and as a bridge to curative surgery. This procedure avoids two-stage surgeries and reduces the probability of permanent colostomy and its complications with the consequent deterioration in quality of life. Objective: to report our experience in the placement of SEMS as palliative treatment in neoplastic colorectal obstruction. Design: retrospective, longitudinal, descriptive and observational study. Methods: all patients in whom the same group of endoscopists performed SEMS placement with palliative intent for advanced colorectal cancer between August 2008 and December 2019 were analyzed. Data collected were demographic and clinical variables, technical and clinical success, early and late complications, and survival. Results: SEMS were placed in 54 patients. The average age was 71 years. Eighty-five percent were left-sided tumors. In 57% of the patients the procedure was performed on an outpatient basis. Technical and clinical success was 92 and 90%, respectively, and median survival was 209 days. The complication rate was 29.6%, including 14.8% obstruction and 5.6% migration. Late mortality attributable to the procedure was 5.6%, caused by 3 late perforations: 2 open and 1 microperforation with localized abscess formation. Conclusions: The placement of SEMS as a palliative treatment for neoplastic colonic obstruction is feasible, effective and safe. It allowed outpa-tient management or brief hospitalization and early refeeding, improving the conditions to face an eventual palliative chemotherapy treatment. Most complications were late and resolved endoscopically on an outpatient basis. (AU)

Uso de stent en estenosis colorrectal benigna / Stent utilization in benign colorectal stenosis

Introducción. La estenosis colorrectal benigna hace referencia a una condición anatómica caracterizada por una disminución del diámetro de la luz intestinal distal a la válvula ileocecal, ocasionando una serie de signos y síntomas de tipo obstructivo. Es una entidad poco frecuente, secundaria en la gran mayoría de veces a la realización de anastomosis intestinales al nivel descrito. El objetivo de esta investigación fue determinar la utilidad del stentcolónico en estenosis secundaria a patología colorrectal no neoplásica. Métodos. Estudio descriptivo de una cohorte de pacientes que desarrolló estenosis colorrectal de origen benigna confirmada por colonoscopía, en 3 hospitales de alta complejidad de la ciudad de Medellín, Colombia, entre los años 2007 y 2021. Resultados. Se incluyeron 34 pacientes con diagnóstico de estenosis colorrectal de origen benigno, manejados con stents metálicos autoexpandibles. La mediana de seguimiento fue de 19 meses y se obtuvo éxito clínico en el 73,5 % de los casos. La tasa de complicación fue del 41,2 %, dada principalmente por reobstrucción y migración del stent, y en menor medida por perforación secundaria a la colocación del dispositivo. Conclusión. Los stents metálicos autoexpandibles representan una opción terapéutica en pacientes con obstrucción colorrectal, con altas tasas de mejoría clínica en pacientes con patología estenosante no maligna. Cuando la derivación por medio de estoma no es una opción, este tipo de dispositivos están asociados a altas tasas de éxito clínico y mejoría de la calidad de vida de los pacientes

Introduction. Benign colorectal stenosis refers to an anatomical condition characterized by a decrease in the diameter of the intestinal lumen distal to the ileocecal valve, which might cause a series of obstructive signs and symptoms. It is a rare entity, caused in the vast majority of cases due to intestinal anastomosis at the described level. The purpose of this study is to determine the performance of colonic stents in the management of non-malignant colorectal strictures. Methods. Descriptive study of a cohort of patients who developed a benign colorectal stenosis confirmed by colonoscopy in three high-complexity hospitals in the city of Medellín, Colombia, between 2007 and 2021. Results. Thirty-four patients diagnosed with benign colorectal stenosis managed with self-expanding metal stents were included in the study. Median follow-up was 19 months, obtaining clinical success in 73.5% of cases, with a complication rate of 41.2%, mainly due to reobstruction and migration of the stent, and to a lesser extent due to perforation secondary to device placement.Conclusion. Self-expanding metallic stents represent a therapeutic option in patients with colorectal obstruction caused by non-malignant stenosing pathology. When diversion through a stoma is not an option, this type of device is associated with high rates of clinical success and improvement in the patients' quality of life

Treatment of obstructive colorectal cancer / 中华胃肠外科杂志

Obstructive colorectal cancer is a common malignant bowel obstruction. Colostomy or colostomy following tumor resection may be the first choice for emergency surgery. The intestinal and systemic conditions of patients undergoing emergency surgery are often poor, and patients need to undergo multiple operations, which increase the surgical risk and economic burden and reduce the quality of life of patients. Poor intraoperative visualization may also affect the radical operation of emergency surgery. Transanal decompression tube (TDT) can rapidly decompress and drain the obstructed bowel, effectively relieve obstruction symptoms, and improve the success rate of primary radical resection. The TDT squeeze the tumor lightly, causing no spread of tumor cells, and is cheap, but the cavity of transanal decompression tube is small and easily blocked, and requires tedious flushing or regular replacement. Self-expanding metallic stents (SEMS) can relieve intestinal obstruction effectively, provide sufficient preparation time for preoperative examination and improvement of nutritional status. By improving patient's tolerance to radical surgery, SEMS might be used as an important treatment strategy choice for obstructive colorectal cancer. However, SEMS may squeeze the tumor, leading to the spread of tumor cells, increase the recurrence rate and metastasis rate, and reduce the survival rate. Moreover, intestinal wall edema still existed during the operation following SEMS, and the rate of ostomy after anastomosis was as high as 34%. We hypothesized that prolonging the interval between stent insertion and surgery to 2 months, with neoadjuvant chemotherapy administered during this interval (SEMS-neoadjuvant chemotherapy strategy), would help improve outcomes. The SEMS-neoadjuvant chemotherapy strategy is a safe, effective, and well tolerated treatment approach with a high laparoscopic resection rate, low stoma formation rate and improvement in the overall survival for patients with left-sided colon cancer obstruction. The patient physical status is improved, the primary tumor is downstaged, and intestinal wall edema is relieved during the relatively longer interval between SEMS placement and surgery. The SEMS-neoadjuvant chemotherapy strategy may be a preferred therapeutic strategy for obstructive left colon cancer.

Tratamiento endoscópico de una fístula aguda tras gastrectomía vertical laparoscópica / Endoscopic treatment of an acute fistula after laparoscopic sleeve gastrectomy / Tratamento endoscópico de uma fístula aguda após gastrectomia vertical laparoscópica

La fístula gástrica aguda es una de las principales complicaciones vinculadas a la gastrectomía vertical laparoscópica (GVL). Existen múltiples opciones terapéuticas para su resolución, siendo el tratamiento endoscópico mediante colocación de clips o stents uno de los más importantes. La aplicabilidad de cada método va a depender del tipo de fístula y del estado del paciente. Presentamos el caso de una mujer de 35 años, que desarrolla una fístula aguda posterior a una GVL. Se realiza tratamiento endoscópico con colocaciónn del sistema "over-the-scope clip" (Ovesco®) a nivel del orificio fistuloso, con posterior colocaciónn de stent metálico auto expandible.

Acute gastric fistula is one of the main complications associated with laparoscopic vertical gastrectomy (LVG). There are multiple therapeutic options for its resolution, being endoscopic treatment by placing clips or stents one of the most important. The applicability of each method will depend on the type of fistula and the patient's condition. We present the case of a 35-year-old woman who developed an acute fistula after LGV. Endoscopic treatment is performed with placement of the over-the-scope clip system (Ovesco®) at the level of the fistulous orifice, with subsequent placement of a self-expanding metal stent.

A fístula gástrica aguda é uma das principais complicações associadas à gastrectomia vertical laparoscópica (GVL). Existem múltiplas opções terapêuticas para a sua resolução, sendo o tratamento endoscópico com colocação de clipes ou stents uma das mais importantes. A aplicabilidade de cada método dependerá do tipo de fístula e do estado do paciente. Apresentamos o caso de uma mulher de 35 anos que apresentou uma fístula aguda após GVL. O tratamento endoscópico foi realizado com a colocação do sistema de clipe over-the-scope (Ovesco®) no nível do orifício fistuloso, com posterior colocação de stent metálico autoexpansível.

Paliación endoscópica con stent duodenal en cáncer gástrico estadio IV complicado con estenosis gastroduodenal / Endoscopic stenting for palliation of Stage IV gastric cancer with malignant gastric outlet obstruction. A clinical case / Paliação endoscópica com stent duodenal em câncer gástrico estágio IV complicado por estenose gastroduodenal. Caso clínico

Resumen: Introducción: el cáncer gástrico es la quinta neoplasia en frecuencia a nivel mundial. Su diagnóstico suele ser tardío. La estenosis gastroduodenal es una complicación frecuente, que condiciona el pronóstico y el tratamiento. Contamos con varias modalidades en cuanto a la paliación de esta complicación. Destacamos el tratamiento quirúrgico mediante derivación digestiva (gastroenteroanastomosis), y el tratamiento endoscópico, mediante colocación de un stent o prótesis metalica autoexpandible (PMA). El objetivo es exponer el caso clínico de una paciente portadora de un cáncer gástrico avanzado complicado con estenosis gastroduodenal en la cual se optó por la colocación de una PMA. La bibliografía comparativa entre ambas técnicas es controvertida. Existen estudios importantes que recomiendan la técnica quirúrgica frente a la endoscópica, y viceversa. Con este fin se han realizado múltiples trabajos. Los posibles beneficios de la paliación endoscópica son: menor estadía hospitalaria, rápido reintegro a la vía oral. El caso clínico expuesto por el contrario no se benefició de la menor estadía hospitalaria, en parte, por ser necesaria su internación por comorbilidades médicas. No presentó complicaciones posteriores relacionadas al procedimiento. Conclusiones: la elección de la técnica a utilizar deberá ser individualizada, teniendo en cuenta el paciente, sus comorbilidades, recursos técnicos, experiencia del personal, y recursos económicos. Se necesitan más estudios para demostrar beneficio de la técnica paliativa más adecuada.

Abstract: Introduction: gastric cancer is the fifth neoplasm in terms of global incidence and its diagnosis often comes late. Gastric outlet obstruction is a frequent complication that influences prognosis and treatment. Among the various modalities available for palliation of this complication, we stand out two: surgical treatment by means of a digestive derivation: gastrojejunostomy and endoscopic treatment, by placing a stent or a steel mesh self-expanding endoprosthesis (EMP). The study aims to present the clinical case of a patient carrier of advanced gastric cancer with gastric outlet obstruction, who was treated by placing a self-expandable metallic stent. Comparative bibliography of both techniques is controversial. A number of important studies recomend the surgical technique instead of endoscopic treatment, and viceversa. For this reason, several studies have been conducted. The potential benefits of endoscopic palliation are the following: shorter hospital stay, fast return to oral intake. However the clinical case presented did not benefit from a shorter hospital stay, since it required longer hospitalization, partly due to medical comorbilities. There were no complications after the procedure. Conclusions: the specific technique to treat the condition needs to be chosen for each individual case, considering the particular patient and his or her comorbilities, technical resources, the experience of the medical staff and economic resources. More studies are necessary to prove the benefits of the most appropriate palliative technique.

Resumo: Introdução: o câncer gástrico é a quinta neoplasia em frequência no mundo. Seu diagnóstico costuma ser tardio. A estenose gastroduodenal é uma complicação frequente, que determina o prognóstico e o tratamento. Existem várias modalidades quanto à paliação desta complicação entre os quais destacamos o tratamento cirúrgico por derivação digestiva: gastro enteroanastomose e o tratamento endoscópico, com colocação de Stent ou Prótese Metálica Autoexpansível (PMA). O objetivo deste trabalho é apresentar o caso clínico de um paciente com câncer gástrico avançado complicado por estenose gastroduodenal em que se optou pela colocação de PMA. A bibliografia comparativa entre as duas técnicas é controversa. Existem estudos importantes que preconizam a técnica cirúrgica em detrimento da endoscópica e vice-versa. Para isso, vários trabalhos foram realizados. Os possíveis benefícios da paliação endoscópica são: menor tempo de internação, rápida reintrodução à via oral. Neste caso o paciente não se beneficiou do menor tempo de internação, em parte, porque a internação foi necessária por comorbidades médicas. Não foram observadas complicações subsequentes relacionadas ao procedimento. Conclusões: a escolha da técnica a ser utilizada deve ser individualizada, levando em consideração o paciente, suas comorbidades, os recursos técnicos, a experiência da equipe e os recursos econômicos. Mais estudos são necessários para demonstrar o benefício da técnica paliativa mais adequada.

Stents metálicos autoexpandibles para el manejo endoscópico de las fístulas esofagogástricas / Self-expanding metal stents for endoscopic management of esophageal and gastric fistulas

Resumen Objetivos: mostrar la eficacia y seguridad de los stents metálicos autoexpandibles para el manejo endoscópico de las fístulas esofágicas. Materiales y métodos: se evalúo una serie de casos de manera retrospectiva entre el 2007 y el 2017, en los que se manejaron a 11 pacientes con un stent metálico autoexpandible para el manejo de fístula esofágica, en quienes se realizó el diagnóstico por clínica, endoscopia digestiva alta o estudios radiológicos en la unidad de gastroenterología del Hospital Universitario San Ignacio (HUSI) de Bogotá D. C., Colombia. Resultados: el principal síntoma inicial fue la disnea en 27,3 % de los casos, seguido por tos en un 18,2 %. El hallazgo más frecuentemente encontrado durante el seguimiento fue el derrame pleural en el 36,4 %, se realizó el diagnóstico de fístula en el 45,5 % con esofagograma y el tipo de lesión más reportada fue la fuga en la anastomosis esofagoentérica, con un 45,5 %, seguida de la esofagopleural, con un 36,4 %; y estos pacientes fueron manejados con un stent metálico autoexpandible. En el 100 % hubo éxito técnico y la resolución del defecto se evidenció en el 72,7 % de los casos. La única complicación reportada fue el desplazamiento del stent en el 27,3 %, y en un paciente se requirió el cambio del stent en 3 oportunidades. El promedio de estancia hospitalaria fue de 41,5 días. Conclusiones: el manejo endoscópico de las fístulas esofagogástricas con stents metálicos autoexpandibles es efectivo y seguro, con una baja tasa de complicaciones.

Abstract Objective: To demonstrate the efficacy and safety of self-expanding metal stents for endoscopic management of esophageal fistulas. Materials and methods: Retrospective case series between 2007 and 2017. A total of 11 patients were treated with self-expanding metal stents for esophageal fistula management, after being diagnosed based on symptoms, upper endoscopy, and/or radiological studies in the gastroenterology unit of the Hospital Universitario San Ignacio (HUSI) in Bogotá D.C, Colombia. Results: The most common initial symptom was dyspnea in 27.3% of cases, followed by cough in 18.2%. The most frequent finding during follow-up was pleural effusion in 36.4% of the cases, of which 45.5% received a diagnosis of fistula through esophagogram. The most reported lesion was esophagoenteric anastomotic leak with 45.5%, followed by esophagopleural injury with 36.4%; these patients were those who received self-expanding metal stent management. Technical success was achieved in 100% of the cases, and the defect was resolved in in 72.7% of them. The only complication reported was stent migration in 27.3%, requiring 3 changes in 1 patient. The average hospital stay was 41.5 days. Conclusions: Endoscopic management of esophagogastric fistulas with self-expanding metal stents is effective and safe, with a low complication rate.

Implantación endovascular urgente de stent en disección aórtica aguda tipo III de DeBakey / Emergency endovascular stent graft implantation for acute traumatic DeBakey type III aortic dissection

RESUMEN El tratamiento de las enfermedades de la aorta torácica con la implantación percutánea de stent se viene realizando desde su aplicación, por primera vez, a principios del siglo XX. Se presenta un paciente de 79 años de edad que fue llevado a urgencias con intenso dolor de espalda posterior a un accidente automovilístico, a quien se le realizó tomografía computarizada y se le diagnosticó una disección aórtica tipo III de DeBakey. Se le implantó un stent endovascular autoexpandible de nitinol (Talent Stent Graft, Medtronic) en la aorta descendente, donde comenzaba el segmento disecado. Este procedimiento es un método eficaz para prevenir la isquemia de órganos y la ruptura vascular en las enfermedades traumáticas de la aorta. Es menos invasivo, tiene menos complicaciones que el tratamiento quirúrgico, y es efectivo para restituir el flujo sanguíneo de forma rápida y segura.

ABSTRACT The applications of thoracic aorta pathologies with a stent graft percutaneously have been performed for the first time since the beginning of the 20th century. Computed tomography was performed on a 79-year-old patient who was brought to the emergency room due to an in-vehicle traffic accident with severe back pain, and DeBakey type III aortic dissection was determined. An endovascular self-expanding nitinol stent (Talent Stent Graft, Medtronic) was implanted in the descending aorta where the dissected segment begins. Stent graft implantation is an effective method in preventing organ ischemia and rupture in traumatic aortic pathologies. This procedure is less invasive and has less complication than surgical approach. It is effective in providing blood flow quickly and safely.

Perforación de sigma secundaria a migración de prótesis biliar / Sigma Perforation Secondary to Migration of Biliary Prosthesis

RESUMEN Introducción: La migración de una prótesis en la vía biliar es una complicación muy poco frecuente que normalmente se expulsa de forma natural, pero en raras ocasiones puede cursar con complicaciones severas. Objetivo: Describir una complicación rara por migración de una prótesis biliar. Caso clínico: Se presenta un paciente de sexo masculino de 75 años, portador de stent biliar que presenta una perforación de sigma secundaria a migración de la prótesis. Conclusiones: Las migraciones protésicas deben vigilarse y si no se eliminan de manera espontánea o el paciente presenta síntomas, se debe proceder a su retirada endoscópica o quirúrgica(AU)

ABSTRACT Introduction: Migration of a prosthesis in the bile duct is a very rare complication normally expelled in a natural way, but on rare occasions it can lead to severe complications. Objective: To describe a rare complication due to migration of biliary prosthesis. Clinical case: A case is presented of a 75-year-old male patient with a biliary stent who presented a sigmoid perforation secondary to migration of the prosthesis. Conclusions: Prosthetic migrations should be monitored and, if they are not eliminated spontaneously or the patient presents with symptoms, they should be removed endoscopically or surgically(AU)

Safety performance of self-expandable NiTi alloy stent / 生物医学工程学杂志

In order to evaluate the safety performance of self-expandable NiTi alloy stents systematically, the dynamic safety factor drawn up by International Organization for Standardization, was used to quantitatively reflect the safety performance of stents. Based on the constitutive model of super-elastic memory alloy material in Abaqus and uniaxial tensile test data of NiTi alloy tube, finite element method and experiments on accelerated fatigue life were carried out to simulate the self-expansion process and the shape change process under the action of high and low blood pressure for three -type stents of 8×30 mm, 10×30 mm, 12×30 mm. By analyzing the changes of stress and strain of self-expanding NiTi alloy stent, the maximum stress and strain, stress concentration position, fatigue strength and possible failure modes were studied, thus the dynamic safety factor of stent was calculated. The results showed that the maximum stress and plastic strain of the stent increased with the increase of grip pressure, but the maximum stress and strain distribution area of the stent had no significant change, which were all concentrated in the inner arc between the support and the connector. The dynamic safety factors of the three stents were 1.31, 1.23 and 1.14, respectively, which indicates that the three stents have better safety and reliability, and can meet the fatigue life requirements of more than 10 years, and safety performance of the three stents decreases with the increase of stent's original diameter.

A Rare Cause of Angina After Coronary Bypass Grafting; Left İnternal Mammary Artery to Pulmonary Artery Fistula and Successful Treatment with Transcatheter Coil Embolization / Uma Causa Rara de Angina Após Revascularização do Miocárdio: Fístula da Artéria Mamária Interna Esquerda para Artéria Pulmonar e Tratamento Bem-Sucedido com Embolização Transcateter com Molas

Abstract Fistula from left internal mammary artery (LIMA) to pulmonary artery (PA) is rarely encountered in daily practice. In recent years, endovascular therapy options have emerged for the treatment of fistula formations and replaced with surgery. A 53-year-old man admitted to our outpatient clinic with symptoms of typical angina and shortness of breath despite optimal medical therapy. In his relevant history, he had a coronary artery bypass graft (CABG) operation in 2009 in which his LIMA was anastomosed to left anterior descending (LAD) and ramus artery sequentially. Coronary angiography including selective imaging of LIMA demonstrated a fistula formation originating from the proximal portion of the LIMA and draining to PA. After successful closure of fistula with transcatheter coil embolization, the patient was discharged without any complication and symptom. In conclusion, although LIMA to PA fistula is an infrequent clinical condition, it should be considered as a potential cause of persistent angina after CABG operation. Treatment options include conservative medical therapy, surgical ligation and endovascular interventions. The best therapy should be individualised for each patient in respect to patient's symptoms, surgical compatibility and anatomy of fistula.

Resumo A fístula da artéria mamária interna esquerda (AMIE) para a artéria pulmonar (AP) é raramente encontrada na prática diária. Nos últimos anos, opções de terapia endovascular surgiram para o tratamento de formações de fístula e foram substituídas por cirurgia. Um homem de 53 anos de idade, internado em nosso ambulatório com sintomas de angina típica e falta de ar, apesar da terapia clínica ideal. Em seu histórico relevante, ele teve uma cirurgia de revascularização miocárdica (CRM) em 2009, na qual sua AMIE foi anastomosada à descendente anterior esquerda (DAE) e à artéria ramus sequencialmente. A angiografia coronária, incluindo imagens seletivas da AMIE, demonstrou uma formação de fístula proveniente da porção proximal da AMIE e drenando para AP. Após o fechamento bem-sucedido da fístula com embolização transcateter com mola, o paciente recebeu alta sem qualquer complicação e sintoma. Em conclusão, embora fístula entre AMIE e AP seja uma condição clínica pouco frequente, deve ser considerada como uma causa potencial de angina persistente após a operação de revascularização do miocárdio. As opções de tratamento incluem terapia médica conservadora, ligadura cirúrgica e intervenções endovasculares. A melhor terapia deve ser individualizada para cada paciente em relação aos sintomas do paciente, compatibilidade cirúrgica e anatomia da fístula.

Implantação de stent autoexpansível para tratamento de estenose uretral em cão: relato de caso / Implantation of self-expanding stent for treatment of urethral stenosis in dog - case report

O stent endovascular autoexpansível pode ser utilizado como forma de tratamento para estenose uretral em cães. O stent de nitinol é composto por uma liga de níquel e titânio que permite mudanças em suas estruturas sob a influência da temperatura corporal e tem excelente biocompatibilidade na uretra canina. Este estudo relata o caso de um cão, sem raça definida, 14 anos de idade, com histórico de disúria há duas semanas, diagnosticado com grande quantidade de cálculos e microcálculos na bexiga, no colo vesical e na uretra prostática, também cistite e hiperplasia prostática. Depois de tratamento para cistite, orquiectomia e cistotomia para retirada dos cálculos, porém sem melhora clínica após 30 dias de acompanhamento, com o paciente apresentando disúria, foi realizada uretrocistografia retrógrada, que evidenciou estenose da uretra prostática. Esse paciente foi encaminhado para procedimento de implantação de um stent de nitinol na uretra prostática. Imediatamente após o procedimento e até o presente momento, o paciente apresenta micção espontânea, sem qualquer sinal de disúria, sendo este o primeiro relato no Brasil do uso dessa técnica.(AU)

The endovascular stent is used for treatment of urethral stricture in dogs. The nitinol stent is composed by nickel and titanium alloy that allows changes in its structures under the influence of body temperature and has excellent biocompatibility in the canine urethra. This study aims to report a case of a 14 - year - old male dog without defined breed with dysuria for two weeks. Ultrasonographic evaluation revealed microcalculi and calculi in bladder, prostatic urethral obstruction and prostatic hyperplasia. Cystotomy was performed to remove uroliths, but after 30 days of hospitalization there was no clinical improvement. A double-contrast retrograde urethrocystography was performed and showed persistence of prostatic urethral obstruction. The pacient was submitted to a new surgery to place a self-expanding nitinol stent and presented spontaneous urination after the procedure. This is the first report of this technique in Brazil.(AU)

Seguridad y eficacia del uso de prótesis metálicas autoexpandibles en el manejo de estenosis malignas de la vía biliar irresecables / Safety and efficacy of the use of self-expanding metal stents in the management of unresectable malignant biliary stenosis

Antecedentes: En los últimos años se ha producido un incremento del uso de prótesis metálicas autoexpandibles (SEMS) en pacientes con estenosis malignas irresecables de la vía biliar. Sin embargo, en Perú no se cuentan con reportes sobre la seguridad y eficacia de este procedimiento. Objetivo: Evaluar la seguridad y eficacia del uso de las SEMS en el manejo paliativo de las estenosis malignas de la vía biliar. Materiales y métodos: Cohorte retrospectiva. Se incluyeron a todos los pacientes referidos para colocación de SEMS biliar como parte de un tratamiento paliativo entre enero del 2016 y agosto del 2018. Se obtuvieron las tasas de colocación exitosa de las SEMS, de paliación adecuada de la obstrucción y de complicaciones asociadas al procedimiento. Se evaluó la patencia de la prótesis durante el seguimiento. Se determinó la supervivencia luego de la colocación de la prótesis. Resultados: Se incluyeron 32 pacientes con indicación de manejo paliativo debido a una estenosis maligna irresecable de la vía biliar. El cáncer de páncreas (56,25%) seguido del colangiocarcinoma (31,25%) fueron las etiologías más frecuentes. Se alcanzó una tasa de colocación exitosa en primera intención de 96,97%. La paliación adecuada de la obstrucción biliar se alcanzó en el 100% de los pacientes (p<0,05). Dos SEMStc migraron durante el seguimiento (6,25%) siendo manejados con la colocación de una nueva SEMSnc. Conclusiones: La colocación de SEMS constituye una estrategia segura, con alta tasa de éxito terapéutico en el manejo paliativo de los pacientes con obstrucción maligna de la vía biliar.

Background: In recent years there has been an increase in the use of self-expanding metallic stents (SEMS) in patients with unresectable malignant stenosis of the bile duct. However, in Peru there are no reports on the safety and efficacy of this procedure. Objective: To evaluate the safety and efficacy of the use of SEMS in the palliative management of malignant stenosis of the bile duct. Materials and methods: Retrospective cohort. All patients referred for placement of biliary SEMS as part of a palliative treatment between January 2016 and August 2018 were included. Rates of successful placement of SEMS, adequate palliation of the obstruction, and complications associated with the procedure were obtained. The patency of the prosthesis was evaluated during follow-up. Survival was determined after placement of the prosthesis. Results: We included 32 patients with indication of palliative management due to an unresectable malignant stenosis of the bile duct. Pancreatic cancer (56.25%) followed by cholangiocarcinoma (31.25%) were the most frequent etiologies. A successful first-time placement rate of 96.97% was achieved. Adequate palliation of biliary obstruction was achieved in 100% of patients (p<0.05). Two SEMStc migrated during follow-up (6.25%) being managed with the placement of a new SEMSuc. Conclusions: The placement of SEMS is a safe and effective therapeutic strategy in the palliative management of patients with malignant obstruction of the biliary tract.

Safety Evaluation of Paclitaxel-Eluting Biliary Metal Stent with Sodium Caprate in Porcine Biliary Tract

BACKGROUND/AIMS: Metallic stents designed to relieve malignant biliary obstruction are susceptible to occlusive tumor ingrowth or overgrowth. In a previous report, we described metallic stents covered with paclitaxel-incorporated membrane (MSCPM-I, II) to prevent occlusion from tumor ingrowth via antitumor effect. This new generation paclitaxel-eluting biliary stent is further endowed with sodium caprate (MSCPM-III) for enhanced drug delivery. The purpose of this study is to examine the safety of its drug delivery system in the porcine biliary tract. METHODS: MSCPM-III (10% [wt/vol] paclitaxel) and covered metal stents (CMSs) were endoscopically inserted in porcine bile ducts in vivo. Histologic biliary changes, levels of paclitaxel released, and various serum analytes (albumin, alkaline phosphate, aspartate transaminase, alanine transaminase, total protein, total bilirubin, and direct bilirubin) were assessed. RESULTS: Based on the intensity of reactive inflammation and fibrosis, changes in porcine biliary epithelium secondary to implanted MSCPM-III were deemed acceptable (i.e., safe). Histologic features in the MSCPM-III and CMS groups did not differ significantly. In a related serum analysis, paclitaxel release from MSCPM-III stents was below the limit of detection for 28 days. Biochemical analyses were also similar for the two groups, and no evidence of hepatic or renal toxicity was found in animals receiving MSCPM-III stents. CONCLUSIONS: In a prototypic porcine trial, this newly devised metal biliary stent incorporating both paclitaxel and sodium caprate appears to be safe in the porcine bile duct.

A Novel High-Visibility Radiopaque Tantalum Marker for Biliary Self-Expandable Metal Stents

BACKGROUND/AIMS: Radiopaque metal markers are required to improve X-ray absorption by self-expandable metal stents (SEMSs) to enable precise stent placement. A new tantalum radiopaque marker was recently developed using an ultrasonic spray technique. The aim of the present study was to evaluate the safety and visibility of tantalum markers. METHODS: A total of three beagle dogs were used for a gastrointestinal tract absorption test. Five tantalum markers were placed in the stomach of each dog endoscopically. Excreted tantalum markers were collected, and their weights were compared to the original weights. In radiopacity tests, marker radiopacities on X-ray images were quantified using ImageJ software and compared with those of commercially available metal markers. Finally, the radiographic images of six patients who underwent biliary SEMS placement using tantalum marker Nitinol SEMSs (n=3) or gold marker Nitinol SEMSs (n=3) were compared with respect to marker brightness on fluoroscopic images. RESULTS: Absorption testing showed that the marker structures and weights were unaffected. Radiopacity tests showed that the mean brightness and total brightness scores were greater for tantalum markers (226.22 and 757, respectively) than for gold (A, 209 and 355, respectively; B, 204.96 and 394, respectively; C, 194.34 and 281, respectively) or platinum markers (D, 203.6 and 98, respectively). On fluoroscopic images, tantalum markers had higher brightness and total brightness scores (41.47 and 497.67, respectively) in human bile ducts than gold markers (28.37 and 227, respectively). CONCLUSIONS: Tantalum markers were found to be more visible than other commercially available markers in X-ray images and to be resistant to gastrointestinal absorption.

Experiencia con los stents metálicos autoexpandibles para el manejo de cáncer gástrico distal / Auto-expandable metal stent in the management of distal stomach cancer

Objetivos: Establecer la eficacia y seguridad de los stents metálicos antroduodenales para el tratamiento del síndrome pilórico en pacientes con cáncer gástrico distal. Materiales y métodos: Se obtuvo datos de 31 pacientes mayores de 18 años que tenían diagnóstico de cáncer gástrico distal entre el año 2009 y el año 2017, quienes presentaban síndrome pilórico asociado a estenosis antroduodenal documentada por endoscopia o radiografía de vías digestivas altas, siendo manejados con stent metálico autoexpandible antroduodenal en la unidad de gastroenterología del Hospital Universitario San Ignacio (HUSI) de Bogotá D.C, Colombia. Resultados: El principal síntoma documentado que motivó a consultar fue la presencia de vómito en el 45,1%, seguido por pérdida de peso 16,13% y hemorragia de vías digestivas altas 19,35%, realizándose el diagnóstico en el 74,19% de los casos con endoscopia de vías digestivas altas. El 96,7% de los pacientes presentaban metástasis al momento del diagnóstico de síndrome pilórico. El 100% de los pacientes tuvo éxito técnico en relación al implante del stent con posterior resolución de síntomas en el 96,77%, siendo la complicación más frecuente el desplazamiento en un 16,13%. Conclusiones: Los stents metálicos autoexpandibles para el manejo de la obstrucción al tracto de salida gástrico secundario a cáncer gástrico distal es un método seguro y eficaz como tratamiento paliativo, mejorando la morbilidad y mortalidad en comparación con el manejo quirúrgico.

Objectives: To establish the efficacy and safety of antroduodenal metal stents for the treatment of pyloric syndrome in patients with distal gastric cancer. Materials and methods: Data were obtained from 31 patients older than 18 years who had a diagnosis of distal gastric cancer between 2009 and 2017, who presented pyloric syndrome associated with antroduodenal stenosis documented by endoscopy or X-ray of upper digestive tract, being managed with an antroduodenal auto-expandable metal stent in the gastroenterology unit of the San Ignacio University Hospital (HUSI) in Bogotá DC, Colombia. Results: The main documented symptom that led to consultation was the presence of vomiting in 45.1%, followed by weight loss 16.13% and upper digestive tract bleeding 19.35%, the diagnosis being made in 74.19 % of cases with endoscopy of upper digestive tract. 96.7% of the patients presented metastases at the time of diagnosis of pyloric syndrome. 100% of patients had technical success in relation to stenting with subsequent resolution of symptoms in 96.77%, the most frequent complication being displacement in 16.13%. Conclusions: Auto-expandable metal stents for the management of gastric outlet tract obstruction secondary to distal gastric cancer is a safe and effective method as a palliative treatment, improving morbidity and mortality compared to surgical management.

TOKYO criteria: Standardized reporting system for endoscopic biliary stent placement

Placement of a plastic or metal stent via endoscopic retrograde cholangiopancreatography (ERCP) currently serves as the first-line procedure for obstructive jaundice and acute cholangitis. Dysfunction of the biliary stent causes recurrence of symptoms and often requires reinterventions and hospitalizations. Therefore, duration of stent patency is commonly used as the primary endpoint in clinical studies of biliary stents. However, owing to considerable heterogeneity between studies in reporting of biliary stent patency, it has been difficult to compare and integrate results of independent studies. There has been between-study heterogeneity in definitions of stent patency, statistics reported for survival curves of stent patency, and methods to treat censored cases. In addition to stent occlusion, stent migration is a major cause of recurrent biliary obstruction after covered metal stent placement, which further complicates the reporting of stent patency. Reporting of functional success and adverse events has been also inconsistent between the studies. From the perspective of evidence-based medicine, the variations in the definitions of outcome variables potentially hinder robust meta-analyses. To overcome the issues due to the lack of outcome reporting guidelines on the topic, the TOKYO criteria 2014 for reporting outcomes associated with endoscopic transpapillary placement of biliary stents have been proposed. Due to their comprehensiveness, the TOKYO criteria can be readily utilized to evaluate various types of biliary stent placement using ERCP, irrespective of types of stents and location of biliary stricture. In this article, we review the TOKYO criteria as a standardized reporting system for endoscopically-placed biliary stents. We also discuss potential controversial issues in the application of the TOKYO criteria. Given that endoscopic ultrasound-guided biliary drainage is increasingly utilized for cases with failed ERCP or altered gastrointestinal anatomy, we further propose a potential application of the TOKYO criteria to reporting of outcomes of this procedure.

Which is better for unresectable malignant hilar biliary obstruction: Side-by-side versus stent-in-stent?

Biliary drainage is required for the management of unresectable malignant hilar biliary obstruction (UMHBO), and endoscopic transpapillary drainage is the first-line therapy because it is less invasive. Self-expandable metallic stents (SEMSs) are superior to plastic stents because they have longer stent patency and are more cost-effective. Endoscopic bilateral SEMS placement is technically challenging compared to unilateral placement. However, recent developments in devices and techniques have facilitated bilateral SEMS placement. There are two methods for bilateral hilar SEMS placement for UMHBO: side-by-side (SBS) and stent-in-stent (SIS). Sequential SBS was commonly conducted for bilateral hilar SEMS placement. In a new and thinner delivery system that was developed for SEM placement, two SEMSs could be simultaneously inserted and deployed through the working channel. This new bilateral stenting method enabled us to accomplish simultaneous SBS placement, which increased the success rate of SBS. Insertion of the guidewire and delivery of the second SEMS through the mesh of the first SEMS is challenging in SIS. Newly designed or modified SEMSs that are suitable for SIS have been developed to overcome this challenge, and these SEMSs have facilitated SIS. Uncovered SEMS has been commonly used for hilar SEMS placement, but covered SEMS (CSEMS) is another option for hilar SEMS placement, because CSEMS prevents tumor ingrowth and allows for removal of the stent for re-intervention. Therefore, CSEMS can be used for bilateral SEMS placement in SBS. There are many methods and kinds of SEMS available for bilateral SEMS placement. However, due to lack of evidence, there is no consensus on whether SBS or SIS is optimal for bilateral hilar SEMS placement. In this review, we compared various outcomes between SBS and SIS from previous studies, to clarify which method is better for bilateral SEMS placement for UMHBO.

The vanishing stent: Repeated fracture and dissolution of nitinol gastric stents in a long term cancer survivor

Nitinol self expandable metal stents are increasingly utilised for malignant obstruction in the proximal gastrointestinal tract. We describe a case in which repeated fracture of proximal duodenal stents with dissolution of the nitinol wire skeleton and covering membranes occurred in a long term cancer survivor. This necessitated placement of 4 stents for symptom control and to allow oral feeding until the patient's death 20 months after the initial stent was inserted. Fracture of gastric and duodenal stents has rarely been described previously, some incidences of which were considered due to mechanical causes. Dissolution of stent metal skeletons has not previously been recognised in gastroduodenal stents but has been described in an oesophageal stent subject to reflux of gastric content and a biochemical mechanism has been proposed. With modern oncological treatment the prospect of patients outliving their stents is increasing and the need for repeat procedures should form part of the consent process.

Covered Self-expandable Metallic Stent Insertion as a Rescue Procedure for Postoperative Leakage after Primary Repair of Perforated Duodenal Ulcer / 대한소화기학회지

Surgery has been the standard treatment for perforated duodenal ulcers, with mostly good results. However, the resolution of postoperative leakage after primary repair of perforated duodenal ulcer remains challenging. There are several choices for re-operation required in persistent leakage from perforated duodenal ulcers. However, many of these choices are complicated surgical procedures requiring prolonged general anesthesia that may increase the chances of morbidity and mortality. Several recent reports have demonstrated postoperative leakage after primary repair of a perforated duodenal ulcer treated with endoscopic insertion using a covered self-expandable metallic stent, with good clinical results. We report a case with postoperative leakage after primary repair of a perforated duodenal ulcer treated using a covered self-expandable metallic stent.