CORRESPONDENCE CT Classification and Endovascular Management of Isolated Dissection of the Superior Mesenteric Artery with Anatomical Variations
J.Y. Luan, X. Li* Department of Interventional Radiology and Vascular Surgery, Peking University Third Hospital, Beijing, China
Dr Neale and colleagues described an interesting case with two so-called anatomical variations. However, the absence of the ileocolic branch might be caused by developmental variation or occlusion owing to extension of the dissection. Although the ileocolic artery was a constant branch of the SMA,1 the absence of the ileocolic branch was observed in 25% cases.2 According to our classification scheme,3 types C and D were defined with the dissections localized at the curved part of the SMA and extended distally without or with involved ileocolic or distal ileal branches. This did not concern whether there was variation with the ileocolic branch. So, if the absence of the ileocolic branch was caused by developmental variation, the dissection should be categorized as type C. However, if the absence of the ileocolic branch was owing to extension of the dissection, it should be categorized as type D. In addition, the previous three classification schemes were all based on whether the true lumen and false lumen were occluded or thrombosed, and our classification scheme was based on the location and length of the dissection. All four classification schemes did not concern jejunal branches. Thus, a large jejunal branch was present no matter which type the dissection was. As regards management of the patient described by Dr Neale and colleagues, we think that endovascular treatment should be effective. Recanalization of the overall true lumen of the dissecting part could be achieved by percutaneous transluminal angioplasty. Then a bare stent could be placed to cover the curved part of the SMA and the initial part of the dissection to exclude the entry and maintain patency of the true lumen. The large jejunal branch arising from the proximal true lumen could be covered by a bare stent and would not be occluded. It has been reported in literature that branch arteries covered by bare stents could maintain patency.4,5
*Corresponding author. X. Li, North Garden Road 49, Haidian District, Beijing 100191, China. Email-address:
[email protected] (X. Li)
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Available online 10 November 2013 Ó 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ejvs.2013.11.002 DOI of original article: http://dx.doi.org/10.1016/ j.ejvs.2013.10.027
Re. ‘Computed Tomography Imaging Features and Classification of Isolated Dissection of the Superior Mesenteric Artery’ We read with interest the article by Luan and Li classifying isolated dissections of the superior mesenteric artery (SMA).1 Having recently encountered a patient with a “Type C” dissection, we wish to highlight the decision process we undertook as a result of two anatomical variations that did not fall into their or others classifications.2 The first was the absence of an ileocolic branch of the SMA, which manifested as multiple small branches (jejunal/ ileal) arising from a single origin. This occurred immediately distal to the termination of the dissection. The second was the presence of a large jejunal branch arising from the proximal true lumen of the dissection. These two aberrations precluded endovascular surgery as a management option as the jejunal branch required reimplantation while there was no distal landing zone for a stent. The authors describe successful use of their grading system in the management of SMA dissection. However, we wish to emphasise that other anatomical factors must be considered prior to the decision on conservative, endovascular, or operative management. REFERENCES 1 Luan JY, Li X. Computed tomography imaging features and classification of isolated dissection of the superior mesenteric artery. Eur J Vasc Endovasc Surg 2013;46(2):232e5. 2 Sakamoto I, Ogawa Y, Sueyoshi E, Fukui K, Murakami T, Uetani M. Imaging appearances and management of isolated spontaneous dissection of the superior mesenteric artery. Eur J Radiol 2007;64(1):103e10.
E. Neale*, M. Wall, R. Downing Worcestershire Royal Hospital, Charles Hastings Way, Worcester WR5 1DD, UK