Evaluation of the mesenteric arterial vasculature by computed tomography angiography and its implications for colorectal cancer surgery / Avaliação da vasculatura arterial mesentérica pela angiotomografia computadorizada e suas implicações na cirurgia do câncer colorretal

Abstract Objective: To determine the branching patterns of the inferior mesenteric artery (IMA) and to describe the clinical applicability of computed tomography (CT) angiography in the evaluation of these vessels to facilitate the planning of colorectal cancer surgery. Materials and Methods: We included 100 patients who underwent CT angiography of the abdomen and pelvis. The branching patterns of the IMA were examined and classified as type 1 (bifurcated), including 1A (sigmoid and left colic arteries arising from a common trunk), 1B (sigmoid and superior rectal arteries arising from a common trunk) and 1C (sigmoid arteries arising from both trunks); type 2 (trifurcated); and type 3 (no left colic branch). Results: Among the 100 patients evaluated, we found the variant to be type 1A in 9%, type 1B in 47%, type 1C in 24%, type 2 in 16%, and type 3 in 4%. Conclusion: Preoperative CT angiography for evaluating the IMA branching pattern could inform decisions regarding the surgical approach to colorectal cancer.

Resumo Objetivo: Determinar os padrões de ramificação da artéria mesentérica inferior (AMI) e descrever a aplicabilidade clínica da angiografia por tomografia computadorizada na avaliação desses vasos na elaboração das estratégias pré-operatórias de cirurgia de câncer colorretal. Materiais e Métodos: Foram incluídos 100 pacientes submetidos a angiografia por tomografia computadorizada abdominal e pélvica. Os padrões de ramificação da AMI foram examinados e classificados como tipo 1 (bifurcado), incluindo 1A (artérias sigmoide e cólica esquerda originando-se de um tronco comum), 1B (artérias sigmoide e retal superior originando-se de um tronco comum) e 1C (artérias sigmoide originando-se de ambos os troncos); tipo 2 (trifurcado); e tipo 3 (sem ramo cólico esquerdo). Resultados: Do total de participantes incluídos no estudo, a variante do tipo 1A foi observada em 9%, a do tipo 1B em 47%, e a do tipo 1C em 24%. Com relação à variante tipo 2, esta foi observada em 16% dos pacientes, e a do tipo 3, em 4% dos casos. Conclusão O uso da angiografia por tomografia computadorizada pré-operatória para avaliar o padrão de ramificação da AMI pode ajudar a escolher a abordagem cirúrgica no câncer colorretal.

Safety of preoperative branch embolization in patients undergoing evar / Segurança da embolização pré-operatória do ramo em pacientes submetidos a evar

Abstract The purpose of this systematic review is to evaluate the safety of pre-endovascular abdominal aortic aneurysm repair (EVAR) embolization of aortic side branches - the inferior mesenteric artery and lumbar arteries. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed. A search of MEDLINE and DIMENSION databases identified 9 studies published from 2011 to 2021 that satisfied the inclusion and exclusion criteria. These studies were analyzed to detect the incidence of embolization-related complications. A total of 482 patients underwent preoperative aortic side branch embolization, 30 (6.2%) of whom suffered some kind of minor complication. The only major complication observed was ischemic colitis in 4 (0.82%) patients, two (0.41%) of whom died after bowel resection surgery. Regarding these findings, aortic side branch embolization seems to be a safe procedure, with very low percentages of both minor and major complications.

Resumo O objetivo desta revisão sistemática foi avaliar a segurança da embolização de artéria mesentérica inferior (AMI) e artérias lombares (ALs) pré-correção endovascular de aneurisma da aorta abdominal. Foram realizadas pesquisas nas bases de dados MEDLINE e Dimensions. Foram encontrados 9 estudos publicados de 2011 a 2021 que atendiam aos critérios de inclusão e exclusão. Os estudos foram analisados ​​para definir a incidência de complicações relacionadas à embolização. No total, 482 pacientes foram submetidos a embolização de AMI e/ou ALs, dos quais 30 (6,2%) sofreram algum tipo de complicação menor. A única complicação importante observada foi colite isquêmica em 4 (0,82%) pacientes. Dois (0,41%) desses pacientes morreram após cirurgia de ressecção intestinal. Em relação a esses achados, a embolização de AMI e ALs parece ser um procedimento seguro, com um percentual muito baixo de complicações menores e importantes.

Experiencia inicial en nuestro centro con la embolización preventiva de la arteria mesentérica inferior en el tratamiento endovascular de los aneurismas de aorta abdominal / Early experience with preventive embolization of the inferior mesenteric artery in the endovascular treatment of abdominal aortic aneurysms

Introducción: la endofuga de tipo II (EFT2) es la más frecuente tras la reparación endovascular de aneurismas de aorta abdominal (EVAR). Objetivos: analizar la presencia de endofugas de tipo II durante el seguimiento, la regresión del saco aneurismático, la tasa de reintervención debido a EFT2, el análisis de los resultados en nuestra serie de casos tratados con embolización de la AMI antes del implante de la endoprótesis aórtica como método útil para disminuir las EFT2 durante el seguimiento. Material y métodos: análisis retrospectivo de los pacientes tratados en nuestro centro con embolización de la AMI previa al EVAR en el periodo 2019-2021. Los criterios utilizados para la embolización de la AMI fueron: diámetro > 3 mm y AL con diámetro > 2 mm o aneurismas aortoilíacos. Se incluyeron 7 pacientes varones (edad media: 72,1 años). El 42 % presentaba aneurismas aortoilíacos. En dos casos se llevó a cabo la embolización de la AMI en un primer tiempo y posteriormente el EVAR; en los restantes se realizó en el mismo procedimiento. El diámetro medio de la AMI fue 5,02 ± 0,9 mm. Todos los pacientes presentaban, al menos, dos AL enfrentadas al origen de la AMI con un diámetro > 2 mm. Resultados: el éxito técnico fue del 100 %. La mediana de seguimiento, 20,7 meses. En los angio TAC al mes y a los 12 meses se objetivó una correcta embolización de la AMI. No hubo fugas de tipo II durante el seguimiento. En todos los casos se visualizó una disminución en el diámetro del saco aneurismático (mediana de regresión: 5,08 mm). No hubo reintervenciones relacionadas con la patología aórtica. Conclusiones: la embolización de la AMI previa al EVAR en pacientes con un diámetro > 3 mm y al menos dos AL con diámetro > 2 mm o aneurismas aortoilíacos parece proteger frente al desarrollo de EFT2 a los 12 meses, a la espera de poder confirmar los resultados a medio y largo plazo. Alto éxito técnico y aceptable regresión del saco aneurismático.(AU)

Introduction: type II endoleak (T2EL), through the inferior mesenteric artery (IMA) or lumbar arteries (LA), is themost common endoleak after endovascular abdominal aortic aneurysm repair (EVAR). Objectives: the primary endpoint was the presence of type II endoleak at follow-up. Secondary endpoints includedaneurysm sac regression and reoperation rate due to T2EL, as well as the analysis of the results in our series of casestreated with IMA embolization prior to the endovascular procedure as a useful method to reduce T2EL at follow-up. Material and methods: this was a retrospective analysis of patients treated at our unit with IMA embolizationprior to EVAR from 2019 through 2021. The criteria used for IMA embolization were IMA diameter > 3 mm, presenceof LA with a diameter > 2 mm, or aortoiliac aneurysms. A total of 7 male patients were included with a mean age of72.1 years. A total of 42 % had aortoiliac aneurysms. In 2 of the cases, IMA embolization was performed initiallyfollowed by EVAR while in the remaining cases it was performed within the same procedure. The mean diameterof IMA was 5.02 mm ± 0.9 mm. All patients had at least 2 LAs facing the origin of the IMA with a diameter > 2 mm.Results: technical success was 100 %. The median follow-up was 20.7 months. In the CCTA performed 1 monthand 12 months postoperatively, correct IMA embolization was observed. There were no type II leaks at follow-up.In all cases, a decrease in the diameter of the aneurysmal sac was observed with a mean regression of 5.08 mm. There were no subsequent reinterventions associated with aortic valve disease. Conclusions: IMA embolization prior to EVAR in patients with a diameters > 3 mm and the presence of at least2 ALs with diameters > 2 mm and/or aortoiliac aneurysms seems to protect against the development of T2EL at12 months, waiting to be able to confirm the results in the mid- and long-term...(AU)

Arterias sigmoideas: bases para una nueva clasificación / Sigmoid arteries: bases for a new classification

Las arterias sigmoideas son ramas de la arteria mesentérica inferior e irrigan al colon sigmoideo. Se originan del tronco de las arterias sigmoideas. Esta es la descripción más frecuente según los autores consultados. El objetivo fue analizar las variaciones en el origen y distribución de las arterias sigmoideas mediante disección. Se utilizaron 13 preparados cadavéricos formolizados al 10 %. Se disecó la cavidad abdominal para identificar a las arterias sigmoideas. Se evidenció su bifurcación paralela al colon sigmoideo. Se lo delimitó mediante reparos palpables. Patrón I: 4 casos (30,8 %). Variante de la arcada sigmoidea como rama colateral de la arteria mesentérica inferior. Tipo Ia: 1 caso (25 %). Sin asociaciones. Tipo Ib: 1 caso (25 %). Asociada al tronco sigmoideo. Tipo Ic: 2 casos (50 %). Asociada a arterias sigmoideas accesorias. Patrón II: 6 casos (46,2 %). Variante del tronco común entre arteria cólica izquierda y arterias destinadas al colon sigmoideo. Tipo IIa: 3 casos (50 %). Sin asociaciones. Tipo IIb: 2 casos (33,3 %). Asociado al tronco sigmoideo. Tipo IIc: 1 caso (16,7 %). Asociado a arterias sigmoideas accesorias. Patrón III: 3 casos (23 %). Variante clásica. Se definió por la ausencia del tronco común con la arteria cólica izquierda y de la arcada sigmoidea. Tipo IIIa: 2 casos (66,7 %). Un número variable de arterias sigmoideas nacen como ramas colaterales de la arteria mesentérica inferior, sin asociarse al tronco sigmoideo. Tipo IIIb: 1 caso (33,3 %). La arteria cólica izquierda emite como rama colateral la primera arteria sigmoidea y se asocia al tronco sigmoideo. 1. El patrón II es el prevalente en este trabajo (46,2 %). 2. La variante clásica no es la predominante en esta investigación (23 %). 3. La arcada sigmoidea tiene 53,8 % de incidencia.

SUMMARY: The sigmoid arteries are branches of the inferior mesenteric artery and supply the sigmoid colon. They originate from the trunk of the sigmoids. This is the most frequent description according to the consulted authors. The objective is to analyze the variations in the origin and distribution of the sigmoid arteries through dissection. 13 cadaveric preparations formalized at 10 % and instruments were used. The abdominal cavity was dissected to identify the sigmoid arteries. Its bifurcation parallel to the sigmoid colon is evident. It is delimited by palpable repairs. Pattern I: 4 cases (30.8 %). Variant of the sigmoid arcade as a collateral branch of the inferior mesenteric artery. Type Ia: 1 case (25 %). No associations. Type Ib: 1 case (25 %). Associated with the sigmoid trunk. Type Ic: 2 cases (50 %). Associated with accessory sigmoid arteries. Pattern II: 6 cases (46.2 %). Variant of the common trunk between the left colic artery and arteries destined for the sigmoid colon. Type IIa: 3 cases (50 %). No associations. Type IIb: 2 cases (33.3 %). Associated with the sigmoid trunk. Type IIc: 1 case (16.7 %). Associated with accessory sigmoid arteries. Pattern III: 3 cases (23 %). Classic variant. It was defined by the absence of the common trunk with the left colic artery and the sigmoid arcade. Type IIIa: 2 cases (66.7 %). A variable number of sigmoid arteries arise as collateral branches of the inferior mesenteric artery, without being associated with the sigmoid trunk. Type IIIb: 1 case (33.3 %). The left colic artery gives off the first sigmoid artery as a collateral branch and is associated with the sigmoid trunk. 1. Pattern II is the most prevalent in this study (46.2 %). 2. The classic variant is not the predominant one in this research (23 %). 3. The sigmoid arcade has a 53.8 % incidence.

Tromboembolismo de la arteria mesentérica inferior con necrosis del territorio de la arteria rectal superior / Thromboembolism of the inferior mesenteric artery with necrosis of the territory of the superior rectal artery

RESUMEN Fundamento: la elevada mortalidad de la isquemia intestinal obliga a llevar a cabo un esfuerzo de coordinación a todos los niveles al actuar con celeridad. Las isquemias segmentarias son menos comunes y lo son, aún más, las del territorio de la arteria mesentérica inferior. Objetivo: exponer un caso poco frecuente de isquemia de la unión rectosigmoidea, provocado por un embolismo de la arteria mesentérica inferior y subsiguiente necrosis del territorio de la rectal superior. Presentación de caso: paciente femenina 76 años de edad ingresada desde hacía 31 días con diagnóstico de enfermedad cerebrovascular tipo infarto cerebral, que el día que se decide su egreso presenta un cuadro sincopal, presentando luego; dolor, distensión y contractura abdominal en cuadrante inferior izquierdo por lo que es intervenida quirúrgicamente, se encontró una necrosis del recto superior y sigmoides bajo (unión rectosigmoidea). Conclusiones: el embolismo de la arteria mesentérica inferior con necrosis segmentaria es una presentación muy rara de esta afección, en la literatura los casos reportados son escasos, esto se debe a las consideraciones anatómicas de las arterias y venas mesentéricas, cuando ocurre la oclusión de las arteria mesentérica inferior suele ser lenta y progresiva con revascularización o si es de forma abrupta la arteria mesentérica superior suple las necesidades de este territorio mediante la arteria de Drummont, lo cual ocurrió en esta paciente pero no con su arteria terminal (punto crítico de Sudeck) necrosándose el rectosigmoides.

ABSTRACT Background: the high mortality of intestinal ischemia requires an effort of coordination at all levels, requiring prompt action. Segmental ischemias are less common and, more so, those of the territory of the inferior mesenteric artery. Objective: to present a rare case of ischemia of the rectosigmoid junction, caused by an embolism of the inferior mesenteric artery and subsequent necrosis of the upper rectal territory. Case presentation: 76-year-old female patient admitted for 31 days with a diagnosis of cerebral infarction-type cerebrovascular disease, which on the day her discharge is decided presents a syncopal picture, presenting later; pain, abdominal distension and contracture in the lower left quadrant, so she undergoes a surgery finding a necrosis of the upper rectum and low sigmoid (recto-sigmoid union). Conclusions: the embolism of the inferior mesenteric artery with segmental necrosis is a very rare presentation of this affection, in the literature the cases reported are scarce, this is due to the anatomical considerations of the mesenteric arteries and veins, when occlusion of the inferior mesenteric artery occurs is usually slow and progressive with revascularization or if abruptly the superior mesenteric artery supplies the needs of this territory through the Drummont artery, which occurred in this patient but not with her terminal artery (Sudeck's critical point) recto-sigmoid necrosis.

Selective intra-arterial embolization to treat hemorrhoids. / Embolización intraarterial selectiva como tratamiento de la patología hemorroidal.

OBJECTIVE: To present our results and describe the technique used for the endovascular treatment of hemorrhoids. MATERIAL AND METHODS: We used right femoral artery or radial artery access to catheterize the inferior mesenteric artery, proceeding to the superior rectal artery with a 2.7F microcatheter to catheterize and embolize each distal branch distally with PVA particles (300-500µm) and proximally with coils (2-3mm). Patients were discharged 24hours after the procedure and clinically followed up at one month by anoscopy. RESULTS: We included 20 patients (4 women and 16 men; mean age, 61.85 years (27-81 years); mean follow-up, 10.6 months (28-2 months). Technical success was achieved in 18 (90%) patients and clinical success in 15 (83.4%); one patient required a second embolization of the medial rectal artery and two required surgery. Recovery was practically painless. At the one-month follow-up, all patients were very satisfied and anoscopy demonstrated marked improvement of the hemorrhoids. There were no complications secondary to embolization. CONCLUSIONS: Our initial results suggest that selective intra-arterial embolization is a safe and painless procedure that is well tolerated because it avoids rectal trauma and patients recover immediately.

An unusual case of colon vascularization by the inferior mesenteric artery / Um caso incomum de vascularização do cólon pela artéria mesentérica inferior

Abstract In this article we present a rare variant in which the large intestine was vascularized by the inferior mesenteric artery. It was encountered during macro and microscopic dissection of the cadaver of a 63-year-old woman at a university department of human anatomy. In this case, the ascending, transverse, descending, and sigmoid colon and rectum were vascularized by the inferior mesenteric artery, whereas the small intestine, cecum and appendix were supplied by the superior mesenteric artery.

Resumo Neste artigo apresentamos uma variação rara em que o intestino grosso era vascularizado pela artéria mesentérica inferior. A variação foi descoberta durante a dissecção macro e microscópia de um cadáver do sexo feminino, 63 anos de idade, em um departamento universitário de anatomia humana. Neste caso, o cólon ascendente, transverso, descendente e sigmoide e também o reto eram vascularizados pela artéria mesentérica inferior, ao passo que o intestino delgado, ceco e apêndice eram vascularizados pela artéria mesentéria superior.

Estudio anatómico de la arteria mesentérica inferior en el hombre / Anatomic study of the inferior mesenteric artery in man

En el presente trabajo se estudió la morfología de la arteria mesentérica inferior y sus ramas, así como su forma de distribución, grosor y cantidad de divisiones y arcadas en el hombre. Para ello se utilizó una muestra de 15 preparaciones anatómicas, obtenidas por el método de macro y macromicrodisección, se realizaron mediciones de los distintos elementos, y se procesaron luego estos datos estadísticos. El sistema de la arteria mesentérica inferior posee un esquema general que va de formas más simples a más complejas según el nivel de desarrollo. Tiene un vaso visceral impar que termina en el borde mesocólico del intestino grueso mediante vasos rectos. Las ramas terminales y las arcadas simples constituyen los elementos que hacen más complejo el árbol vascular intestinal de los mamíferos, pero que alcanzan su desarrollo más elevado en su representante superior: el hombre. Las ramas secundarias en los sitios de emergencia o dicotomización presentan grosores semejantes, así como los vasos rectos que penetran en la pared intestinal, lo que garantiza de esta forma una irrigación uniforme en el órgano.

In this work, morphology of the inferior mesenteric artery and its branches is studied as well as its distribution form, thickeness, and quantity of divisions and arches in man. For this, a sample of 15 anatomic preparations obtained for the microdisecction method, was used. Messurements of different elements were performed , and afterwards these statistical data were processed. The system of the level of developmen. It has and old visceral vessel which ends in the mesocholic border of the large bowel through direct vessels. Ending branches and simple arches are the elements which make more complex the intestinal vascular tree of mammals, but they reach their highest development in its superior representant:man Secondary branches in the emergency sites or dicotomization present similar thickeness, as well as disect vessels that penetrate into the intestinal wall which guarantees a uniform irrigation to the organ.