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.

[Surgeon's role in CT-based preoperative determination of inferior mesenteric artery anatomy in colorectal cancer treatment]. / Rol' khirurga v opredelenii anatomii nizhnei bryzheechnoi arterii po dannym komp'yuternoi tomografii pri lechenii kolorektal'nogo raka.

BACKGROUND: The inferior mesenteric artery (IMA) is a blood vessel of great importance in left colon and rectal cancer surgery. We aimed to determine the role of surgeons in computed tomography (CT) based vascular anatomy interpretation. METHOD: Patients with left colon and rectal cancer treated surgically with D3 lymph node dissection and selective vascular ligation were included in this study. All patients (n=250) underwent preoperative CT with intravenous contrast. The IMA anatomy was schematically depicted by surgeon based on CT interpretation. Intraoperatively anatomy was defined by skeletonisation of the IMA. All patients had segmental resection with selective vascular ligation. The concurrence of prospectively obtained results were evaluated by intraclass correlation and Kendall's tau-b test. Misinterpretation of IMA anatomy was analysed by CT-specialist. RESULTS: The preoperative and intraoperative IMA anatomy features were correctly interpreted in 237 cases (in 94.8%) within skeletonisation extent, which is supported by high level of agreement and concordance of preoperative data regards to intraoperative findings (K=0.926; p<0.001; CC=0.912; p<0.001). As a result of the CT-based evaluation of the IMA, E, K, and H types of branching patterns were proposed. IMV position was mistakenly identified in 2.6% of cases. CONCLUSION: Surgeons are able to evaluate the IMA anatomy accurately with CT and use it in routine preoperative planning. The E, K, and H branching types may be used when defining approach to skeletonisation and level of vascular ligation.

Distance measurements and origin levels of the coeliac trunk, superior mesenteric artery, and inferior mesenteric artery by multiple-detector computed tomography angiography.

The aim of this study is to determine vertebral levels of the coeliac trunk, the superior mesenteric artery, and the inferior mesenteric artery originated from the abdominal aorta and to calculate the distance measurements between these arteries and between these arteries and the aortic bifurcation by multidetector computed tomography angiography technique. It was determined that the nine different vertebral levels of the coeliac trunk, the nine different vertebral levels of the superior mesenteric artery, and the eleven different vertebral levels of the inferior mesenteric artery. The distance measurements between the coeliac trunk and the superior mesenteric artery, the inferior mesenteric artery, the aortic bifurcation were found significant between female and male. In this study, it was determined more different levels than the levels described in classical anatomy. The preoperative information of these morphological variations can contribute to the reduction of surgical time and perioperative vascular complications especially for anterior lumbar interbody fusion and defining the location of the primary lymphatic drainage site for gastrointestinal malignancies.

[Reappraisal of the lateral rectal structure].

Colorectal surgeons have focused on the lateral structure of rectum for a long time and lateral ligament is the common term to depict this structure. A better understanding of lateral rectal structure could be beneficial to performing the total mesorectum excision (TME) procedure and protecting patients' urinary, sexual and defecation function. The main controversies focus on two aspects: (1) Does the lateral ligament exist? (2) What dose it contain? Does the middle rectal artery exist? Up to now, anatomic studies have failed to reach consensus on the lateral rectal structure. However, surgeons do find the lateral rectal ligament during surgery and it may be the pathway for lateral lymph node metastasis in rectal cancer. The lateral rectal structure contains the middle rectal artery, nerve branches, lymphatics and adipose fibrous tissue around them. We summarize our clinical experience and conclude that the middle rectal artery appears in lateral ligament constantly but some of them are too small to be easily observed. Therefore, regarding the perspective of membrane anatomy, embryology and surgery, this structure may be more appropriate to be called the "lateral mesorectum". We propose this new term based on the previous literature and our own experience for the readers' reference.

[Laparoscopic radical resection of rectal cancer with preservation of the left colic artery: anatomical basis and surgical experience].

In order to increase the blood supply of anastomosis, surgeons choose to preserve the left colon artery (LCA) during the laparoscopic radical resection of rectal cancer. However, surgeons are always ailed by hemorrhage and incompletely dissection of No. 253 lymph nodes. One reason is the shortage of understanding the relationship between inferior mesenteric artery (IMA), LCA, and inferior mesenteric vein before surgery. Another reason is that surgeon always remove the lymph nodes around LCA, while don't normatively resect No. 253 lymph nodes, which affect the overall survival rate. Therefore, the "medial-to-lateral approach" for laparoscopic preservation with LCA radical resection in rectal cancer was suggested in this article. The CT technique could be used to analyze the IMA classification, which contribuated to the standard conservation of LCA. Laparoscopic radical resection of rectal cancer could be completed of high quality, through accurate definition and exactly dissection of the No. 235 lymph nodes.

[The angiographic anatomy of the inferior mesenteric artery in elder].

Objective: To examine the characteristics of the digital subtraction angiography of inferior mesenteric artery (IMA) in elderly Chinese patients over 65 years old. Methods: Totally 64 cases who underwent angiography of IMA were selected from the Department of General Surgery, Xuanwu Hospital of Capital Medical University, including 42 males and 22 females, aging (70.9±5.1) years (range: 60 to 88 years). The origin, diameter and trunk length of IMA were analyzed. The distribution of IMA branching and the relationship between LCA and IMV at the level of IMA opening position were revealed. Also, the range of IMA perfusion, Riolan arch and IMA occlusion were observed. Results: All 64 patients underwent IMA angiography successfully. The diameter of IMA was (3.2±0.5) mm (range: 2.6 to 4.4 mm), and the trunk length was (3.8±1.0) cm (range: 1.1 to 7.0 mm). According to IMA classification standard, there were 26 patients with type Ⅰ (40.6%), 24 patients with type Ⅱ (37.5%), 12 patients with type Ⅲ (18.8%), 2 patients with type Ⅳ(3.1%). The horizontal distance between IMV and LCA was less than 0.5 cm in 58 cases (90.6%) and more than 0.5 cm in 6 cases (9.4%). IMA perfusion was interrupted at the splenic flexure in elderly patients in 14 cases (21.9%), including 11 cases terminated at splenic flexure and 3 cases terminated at descending colon. Riolan arch was found in only 4 of 64 patients (6.2%). Two patients (3.1%) had IMA or its branch occlusion, the arterial perfusion were compensated by Drummond arch without Riolan arch. Conclusions: The anatomy of IMA should be taken attention seriously in laparoscopic left-colorectal cancer radical resection. IMA shape, type, blood supply range and the relationship between LCA and IMV could be considered by the angiography or other examination, which can help to determine the ligation position of blood vessels, which could optimize the operation strategy.

Inter-mesenteric connections between the superior and inferior mesenteric arteries for left colonic vascularization: implications for colorectal surgery.

PURPOSE: There is confusion regarding the names, the number, and the exact location of the colonic arterial arches which provide connections between the superior and inferior (IMA) mesenteric arteries at the level of the left colic angle. The aim of this review was to delineate the "true" colic arches arising in the meso of the left colic angle and to describe their surgical implications. METHODS: A systematic review of the literature was performed using the MEDLINE database. The search included only human studies between 1913 and 2018. All dissection, angiographic, arterial cast and corrosion studies were analyzed. RESULTS: The terms "Riolan arch", "marginal artery of Drummond", "meandering mesenteric artery" and "Villemin's arch" must no longer be used in the scientific literature. Three arterial arches were found at the level of the left colic angle, permitting the communication between the two arterial mesenteric systems: (1) the Marginal Artery (the most peripheral, found in 100% of cases); (2) the "V" termination of the ascending branch of the left colic artery (LCA), existing in more than 2/3 of cases; and (3) the inter-mesenteric trunk, found more centrally located and existing in less than 1/3 of cases. CONCLUSIONS: Three arterial arches exist at the level of the left colic angle: (1) the Marginal Artery, (2) the "V" termination of the ascending branch of the LCA, and (3) the inter-mesenteric trunk. The knowledge of this anatomy is essential for performing colorectal surgeries involving ligation of the IMA.

Vascular anatomy of inferior mesenteric artery in laparoscopic radical resection with the preservation of left colic artery for rectal cancer.

AIM: To investigate the vascular anatomy of inferior mesenteric artery (IMA) in laparoscopic radical resection with the preservation of left colic artery (LCA) for rectal cancer. METHODS: A total of 110 patients with rectal cancer who underwent laparoscopic surgical resection with preservation of the LCA were retrospectively reviewed. A 3D vascular reconstruction was performed before each surgical procedure to assess the branches of the IMA. During surgery, the relationship among the IMA, LCA, sigmoid artery (SA) and superior rectal artery (SRA) was evaluated, and the length from the origin of the IMA to the point of branching into the LCA or common trunk of LCA and SA was measured. The relationship between inferior mesenteric vein (IMV) and LCA was also evaluated. RESULTS: Three vascular types were identified in this study. In type A, LCA arose independently from IMA (46.4%, n = 51); in type B, LCA and SA branched from a common trunk of the IMA (23.6%, n = 26); and in type C, LCA, SA, and SRA branched at the same location (30.0%, n = 33). The difference in the length from the origin of IMA to LCA was not statistically significant among the three types. LCA was located under the IMV in 61 cases and above the IMV in 49 cases. CONCLUSION: The vascular anatomy of the IMA and IMV is essential for laparoscopic radical resection with preservation of the LCA for rectal cancer. To recognize different branches of the IMA is necessary for the resection of lymph nodes and dissection of vessels.

Laparoscopic lymph node dissection around the inferior mesenteric artery for left-sided colon and rectal cancer.

Lymph node dissection is a critical part of surgery for colorectal cancer. Japanese D3 and complete mesocolic excision are two unique principles for lymph node dissection in colorectal cancer. Laparoscopic surgery magnifies the targets and provides insight about the micro-anatomy through high-quality, high-definition imaging, which benefits the surgeon. Although laparoscopic colorectal resection is feasible, there is no universal procedure. We describe in detail the anatomy viewed during lymph node dissection around the inferior mesenteric artery. Visual recognition of two folds on both sides of Landzert's fossa is the critical first step, as recognizing these structures allows laparoscopic procedures to be performed safely. Our findings suggest that this procedure is feasible and effective for the surgical treatment of patients with left-sided colon or rectal cancer.

Anatomic variations of inferior mesenteric artery and left colic artery evaluated by 3-dimensional CT angiography: Insights into rectal cancer surgery - A retrospective observational study.

OBJECTIVE: To demonstrate the clinical applicability of 3-dimensional CT angiography (3D-CTA) in evaluating the anatomic variations of inferior mesenteric artery (IMA) and left colic artery (LCA), to help make pre-operative strategies of rectal cancer surgery. METHODS: 188 patients with abdominal and pelvic contrast-enhanced CT scan were retrospectively enrolled and 3D-CTA was reconstructed. The origin and branching patterns of IMA, tracking patterns of LCA, intersectional patterns among IMA, LCA and inferior mesenteric vein (IMV) were examined, and their associations with clinical features were analyzed. RESULTS: The origin of IMA was located 42.1 ± 7.7 mm above iliac artery bifurcation, 64.4% within the area of the 3rd lumbar vertebra. 47.3% of LCA arose independently from IMA, 27.1% arose at the root of sigmoid artery (SA), 20.7% shared a common trunk with SA while 4.8% of LCA was absent. As for track of LCA before anastomosis with marginal artery, 53.2% went straight upward while medial to the inner border of left kidney (Type A), 27.1% traveled diagonally across left kidney (Type B) and14.9% went infero-laterally to the lower border of left kidney (Type C). Short IMA trunk was independently associated with type A LCA and lower site of IMA origin. At the horizontal level of IMA origin, 29% of the LCA went distant from IMV, while 71% (21% medial, 50% lateral) were mutually close, and the close type was independently associated with type A LCA. CONCLUSION: Preoperative understanding of the vascular variations and the mutual relationship among LCA, IMA and IMV could be obtained by 3D-CTA, which would further help surgeons to set detailed plans for laparoscopic rectal cancer surgery.

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.

Colectomy in patients with previous colectomy or occlusive vascular diseases: Pitfalls and precautions.

Two principal branches from the aorta provide the colonic blood supply: the superior and inferior mesenteric arteries. There are numerous anatomical variations, which the surgeon must fully understand before embarking on any colonic surgery. A good knowledge of these variations is particularly important when the patient has already undergone colectomy or presents with occlusive vascular disease. The aim of this review is to summarize the standard anatomy and the main variations of the colonic blood supply as they apply to colorectal surgery in this setting.

Is low tie ligation truly reproducible in colorectal cancer surgery? Anatomical study of the inferior mesenteric artery division branches.

AIM: Curative surgery is the standard treatment for colorectal cancer. The ligation level of the inferior mesenteric artery (IMA) is still debated, as neither low tie (LT) nor high tie ligation (HT) has shown any benefit on the patients' overall survival. We examined whether LT is standardizable and easily reproducible from an anatomical point of view. METHOD: One hundred CT angiographies of healthy patients were analysed for the anatomy of the IMA and its division branches: left colic artery (LCA), sigmoid arteries trunk and superior rectal artery. Data analysed comprised angles between the IMA and the aorta, diameters of the IMA and its branches, repartition of the branches and distances between the origin of the branches and the origin of the IMA. RESULTS: IMA anatomy showed no variation. In contrast, its division branches showed important variability in terms of distance to the origin and repartition: in 19.9% of the patients, the IMA directly splits into three branches, and in 17.6% of the patients, the LCA originated at more than 5 cm from the origin of the IMA. These frequent variations led us to assume that the standardization of LT is very difficult in a context of neoplasm, where the quality of the lymphadenectomy is fundamental. CONCLUSION: The division branches of the IMA are extremely subject to interindividual variations, making it difficult if not impossible to reproduce identically a surgical procedure based on their anatomy. HT appears to us as the only relevant procedure for colorectal cancer.

Are there any surgical and radiological correlations to the level of ligation of the inferior mesenteric artery after sigmoidectomy for cancer?

INTRODUCTION: The Société Française de Chirurgie Digestive and the American Society of Colon and Rectal Surgeons recommend a ligation at the origin of the primary feeding vessel for sigmoid cancer to ensure optimal lymphadenectomy. We evaluated the correlation between the level of ligation defined by the surgeon and the real level of ligation visualized on postoperative CT scan. PATIENTS AND METHODS: From December 2004 to August 2010, in a series of 146 patients undergoing colectomy for sigmoid cancer, 51 (19 women) CT measurements (visualization of the left colonic artery (LCA), length of the arterial stump) were performed by a radiologist blinded to operative data. RESULTS: This series comprised 63% of men with a mean age of 69 years. A correlation was demonstrated between the level of ligation assessed by the surgeon and the real level of ligation demonstrated on postoperative CT scan in 41% of cases. No risk factors for absence of correlation were identified (laparoscopy, gender, BMI, emergency, and ASA score). In the "no correlation" group, the site of ligation was overestimated in 70% of cases. No significant difference was observed between the "correlation" and "no correlation" groups for lymphadenectomy (21.6 and 18 lymph nodes, p=0.5593) or 5-year overall survival (71.4 and 93.1 months, p=0.57). CONCLUSION: In conclusion, the surgical and radiological correlations are low as the intraoperative estimation of the level of IMA ligation was correlated with CT findings in less than 50% of cases. No risk factors for non-correlation were identified, and there was no impact on lymphadenectomy. Overestimation of the level of ligation was the most frequent situation but did not appear to have any impact on tumor staging or on patient management in this group of patients.

The abdominal aorta and its branches: anatomical variations and clinical implications.

BACKGROUND: Vascular variations regarding the branching pattern of the aorta are important in different laparoscopic surgeries, liver and kidney transplantation, oncologic resections, and various interventional radiological procedures in the abdominal region. The present work was undertaken on cadavers to examine the prevalence of vascular patterns of the important branches of the abdominal aorta. MATERIAL AND METHODS: A total of 50 properly embalmed and formalin fixed cadavers were dissected in the abdominal region, and viscera were mobilised to expose the origin of important branches of the abdominal aorta. Celiac trunk, superior mesenteric, inferior mesenteric, right and left renal, left and right gonadal arteries, and the division of the abdominal aorta into right and left common iliac arteries were observed regarding their level of origin and for presence of any anatomical variations. RESULTS: The celiac trunk origin was located at the level of the T12 vertebra in 64% of cadavers, superior mesenteric at L1 in 76%, inferior mesenteric at L3 in 68%, left and right renal at L1 in 82% and 80%, respectively, and left and right gonadal at L2 in 84% and 86%, respectively; whereas the aortic bifurcation was most common at the level of the L4 vertebra in 54% of cadavers. Important anatomical variations were photographed. CONCLUSIONS: Defective fusion of the vitelline arteries during the embryonic stage resulted in the aforementioned anatomical variations. Knowledge of aortic variations is useful for appropriate radio diagnostic interventions and is helpful to decrease complications like vascular bleeding while ligating and anastomosing blood vessels, which is an integral part of many abdominal surgeries.

[The lymph node of Mondor: myth or reality?]. / Le ganglion de Mondor : mythe ou réalité ?

AIM OF THE STUDY: Lymph node involvement is one of the most significant prognostic factors of patients with rectal cancer. Despite major advances in our understanding of the propagation of the rectal cancer, the lymphatic drainage of the rectum remains unclear. This study was designed to assess the number of lymph nodes located around the superior rectal artery and to assess the frequency of Mondor's lymph nodes. PATIENTS AND METHODS: Twenty-five anatomic subjects were studied. All resections were performed using total mesorectal excision. Lymph nodes were sought in the tissue surrounding the superior rectal artery up to 2 cm under the ending of the superior rectal artery by manual dissection and were submitted for histological examination. The correlation between the number of lymph nodes, and the volume and weight of the tissue surrounding the superior rectal artery was evaluated by non-parametric Spearman test. RESULTS: The mean number of lymph nodes per specimen was 2.7 +/- 1.4. The size of the lymph nodes varied between 1 and 7 mm. The lymph nodes were mostly smaller than 3 mm (56%). The number of lymph nodes in the superior rectal mesentery was independent of its volume and its weight. Seven subjects had a Mondor's lymph node. The mean size of Mondor's lymph node was 3.4 +/- 2.1 cm. CONCLUSIONS: The number of NL located around the superior rectal artery is small, varying between 1 and 5. The Mondor's lymph node is an inconstant rectal NL. Its only characteristic is its location in the bifurcation or trifurcation of the superior rectal artery.

Riolan's arch: confusing, misnomer, and obsolete. A literature survey of the connection(s) between the superior and inferior mesenteric arteries.

BACKGROUND: There are 2 interpretations of Riolan's arch: (1) Riolan's arch is identical to a central part of the marginal artery (MA), connecting the superior (SMA) and the inferior mesenteric (IMA) arteries; and (2) Riolan's arch represents a rare artery, connecting the SMA and the IMA. The current review aims to emphasize the clinical importance of the colon's vasculature and to show the feasibility of abolishing the terms "Riolan's arch" and "meandering mesenteric artery." METHODS: A literature survey was performed. RESULTS: It appears that no distinct identity can be ascribed to Riolan's arch and that the "meandering mesenteric artery" represents an angiographically hypertrophied MA and/or the ascending branch of the left colic artery. However, a rare, centrally located, communicating artery has been described. Generally, the MA is sufficient for left colic circulation after ligation of the IMA, but at the splenic flexure, patency of the ascending branch of the left colic artery can be primordial. CONCLUSION: As connections between the SMA and the IMA can be adequately described using structures mentioned in Terminologica Anatomica, the terms "Riolan's arch" and "meandering mesenteric artery" should be abolished.

Anatomical considerations on Sudeck's critical point and its relevance to colorectal surgery.

Sudeck's critical point at the rectosigmoid junction is described as the point of origin of the last sigmoid arterial branch, originating from the inferior mesenteric artery (IMA). There is controversy on the importance of Sudeck's point, and the frequency in which the anastomosis is found. Furthermore, the diameter of the anastomosis, if present, may also impact on the viability of the caudal stump. This study aimed to determine the frequency in which a macroscopic anastomosis occurs, between the superior rectal artery and the last sigmoidal branch, in a cadaver population; the diameter of this anastomosis and the distance from the origin of the IMA to Sudeck's point. Sixty-four cadavers were included in the study, excluding those with previous surgery to the rectosigmoid junction. Sudeck's point was carefully identified and dissected to establish the presence of an anastomosis. Subsequent measurements were performed using a digital caliper (accuracy = 0.01 mm). A macroscopic anatomosis was absent in three cases (4.7%). The mean diameter of the anastomosis when present was 1.9 mm (SD: 0.5 mm), and the distance from the origin of the IMA to Sudeck's point was 55.5 mm (SD: 14.6 mm). Although an anastomosis is present in the majority of cases, the vessel is very small in diameter, and may not be sufficient to meet the demands of the caudal stump. The distance from the origin of the IMA to Sudeck's point is sufficient enough to allow for ligation of the IMA proximal to Sudeck's point.

Origem e distribuição da artéria mesentérica caudal em gatos sem raça definida / Origen y distribución de la arteria mesentérica caudal en gatos sin raza definida (felis catus, linnaeus 1758) / Origin and distribution of the caudal mesenteric artery in cats non-defined race (felis catus, linnaeus 1758)

Os dados da literatura especializada sobre a anatomia dos felinos são escassos e sempre relacionados aos cães. Este trabalho teve como finalidade estudar a origem e a distribuição da artéria mesentérica caudal em gatos, complementando a literatura e contribuindo para a cirurgia nessa espécie. Trabalhou-se com 31 gatos adultos, machos e fêmeas, sem raça definida, obtidos por meio de doações. No sistema arterial desses animais foi injetado Látex Altamira®, corado com pigmento específico, para análise da sistematização arterial da porção final do intestino. Notou-se que, em todos os casos, a artéria mesentérica caudal originou-se da aorta descendente abdominal e emitiu a artéria cólica esquerda e a artéria retal cranial. A artéria cólica esquerda irrigou a porção descendente do cólon, emitindo 2 ramos (3,22% dos casos), 3 (9,68%), 4 (22,58%), 5 (19,35%), 6 (19,35%), 7 (16,13%), 8 (6,45%) e 10 (3,22%). A artéria retal cranial apresentou ramos destinados ao cólon descendente em 90,32% das observações, enviando 1 ramo (32,26% dos animais), 2 (19,35%), 3 (9,64%), 4 (6,45%), 5 (12,90%), 6 (3,22%) e 8 (6,45%). Para o reto, a artéria retal cranial emitiu ramos em todos os gatos, que ocorreram em forma de 1 ramo em 3,22% das peças, 2 (9,68%), 3 (48,39%), 4 (12,90%), 5 (12,90%), 6 (6,45%) e 8 (6,45%)

Data from specialized literature on cat anatomy are scarce and they are always related to dogs. This paper studies the origin and distribution of the caudal mesenteric artery in cats, complementing the literature and contributing to surgery for such species. The project was carried out with 31 grown animals, male and female, without defined race, acquired by donations. Látex Altamira® was injected in the arterial system of these animals and colored with specific pigment for the analysis of the arterial systematization of the final portion of the intestine. It was noticed, in all cases, that the caudal mesenteric artery originated from the descending abdominal aorta and emitted the left colic artery and the cranial rectal artery. The left colic artery irrigated the descendent colon portion of all cats by emitting 2 branches (3.22% of cases), 3 (9.68%), 4 (22.58%), 5 (19.35%), 6 (19.35%), 7 (16.13%), 8 (6.45%), and 10 (3.22%). The cranial rectal artery presented branches towards the descendent colon in 90.32% of the observations, sending 1 branch (32.26% of animals), 2 (19.35%), 3 (9.64%), 4 (6.45%), 5 (12.90%), 6 (3.22%), and 8 (6.45%). Towards the rectum, the cranial rectal artery emitted branches in all cats, what occurred as 1 branch in 3.22% of the pieces, 2 (9.68%), 3 (48.39%), 4 (12.90%), 5 (12.90%), 6 (6.45%) and 8 (6.45%)

Los datos de la literatura especializada sobre la anatomía de los felinos son escasos y siempre relacionados a los perros. Esta investigación tuvo como objetivo estudiar el origen y la distribución de la arteria mesentérica caudal en gatos, complementando la literatura y contribuyendo para la cirugía en esa especie. Se trabajó con 31 gatos adultos, machos y hembras, sin raza definida, procedentes de donaciones. En los vasos arteriales de esos animales fue inyectado Látex Altamira®, teñido con coloraciones específicas, para análisis de la sistematización arterial de la porción final Del intestino. Fue observado que, en todos los casos, la arteria mesentérica caudal se originó de la aorta descendente abdominal y emitió a la arteria cólica izquierda y a la arteria rectal craneal. La arteria cólica izquierda irrigó la porción descendente del colon, emitiendo 2 ramales (3,22% de los casos), 3 (9,68%), 4 (22,58%), 5(19,35%), 6(19,35%), 7(16,13%), 8 (6,45%) y 10 (3,22%). La arteria rectal craneal presentó ramales destinados al colon descendente en 90,32% de las observaciones, emitiendo 1 (32,26% de los animales), 2 (19,35%), 3 (9,64%), 4 (6,45%), 5 (12,90%), 6 (3,22%) y 8 (6,45%). Para el recto, la arteria rectal craneal emitió ramales en todos los gatos, que ocurrieron en forma de 1 ramal en 3,22% de las piezas, 2 (9,68%), 3 (48,39%), 4 (12,90%), 5 (12,90%), 6 (6,45%) y 8 (6,45%)