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Background The endovascular technique has been recommended over the past few years to extracranial carotid dissection and pseudoaneurysm with promising results, especially after medical therapy failure. Flow-diverting stents are an alternative for complex cases. These stents have proven to be effective treatment devices for intracranial aneurysms. Methods The reference list of Pham’s systematic review, published in 2011, and Seward’s literature review, published in 2015, was considered, as well as all new articles with eligible features. Search was conducted on specific databases: MEDLINE and Literatura Latino-Americana e do Caribe em Ciencias da Saude. Results For carotid dissection and pseudoaneurysm, our review yielded 3 published articles including 12 patients. The technical success rate of flow-diverting stent was 100% with no procedural complication described. Mean clinical follow-up was 27.2 months (range 5–48), and in 5 months’ angiographic follow-up, all lesions had healed. No new neurological events were reported during the clinical follow-up. Conclusions Flow diverter stent use on intracranial and peripheral vascular surgery demonstrates satisfactory initial results, but it is still under investigation. There are very few cases treated till now and the initial results with flow-diverting stents to cervical carotid dissection are promising. In well-selected cases, where simple embolization or conventional stent is not appropriate, this technic may be considered.

The objective of this study was to identify the effect of two left renal vasculature occlusion strategies on the duplex ultrasound-assessed rheology and histology of the contralateral kidney.Pigs were randomly assigned to one of two groups: left renal artery-only clamping (A group, n = 8) or left renal artery and vein clamping (AV group, n = 9). Bilateral renal parenchymal biopsy specimens were taken every 10 minutes for 90 minutes. Duplex ultrasound resistive index (RI) and pulsatility index (PI) were measured. Mixed models with normal distribution and first-order autoregressive correlation structure and generalized estimating equation models were used. Results are presented as adjusted means with standard errors, estimated proportions with standard errors, and line plots with 95% confidence intervals.RI and PI increased in the nonischemic kidney. In A group animals, RI values increased significantly (P .01) after 30 minutes of ischemia and PI increased significantly (P .04) from 30 to 60 minutes of ischemia. The number of histologic abnormalities was higher in A group than in AV group biopsy specimens. The percentage of lesions increased significantly after 10 minutes in A group nonischemic kidneys (P .02) and between 50 and 80 minutes in AV group nonischemic kidneys (P .01).Nonischemic kidneys were acutely affected by contralateral ischemia. Their function was more adversely affected by unilateral renal artery occlusion with preserved renal vein patency (A group).

ObjectiveTo elucidate the histologic changes after stent graft oversizing in nonatherosclerotic aortas using an experimental porcine model. We previously reported that the diameter and angulation of the aorta in this model are similar to those in young individuals who undergo stent graft repair for blunt aortic injuries. The lack of commercially available stent grafts specific for repairing blunt aortic injuries, particularly for small and angulated aortas, may be related to the high rate of endograft complications in this population.MethodsTwenty-five pigs were randomized into one control group (without stent graft implantation) and four oversized groups (A: 10%-19%, B: 20%-29%, C: 30%-39%, and D: >40%). Three circumferential fragments were collected from the aorta for histologic and immunohistochemical studies. Morphometric analyzes were performed using an inflow system and image analysis software (Quantimet 500; Leica Cambridge Ltd, Cambridge, UK).ResultsCollagen expression in the aortic wall was not significantly different among the five groups (P = .5604). There were significantly fewer muscle fibers in the aortic wall in the oversized groups compared with the control group (P = .000198). The proportion of elastic fibers in the aortic wall was significantly smaller in the oversized groups compared with the control group (P = .0000001). Immunohistochemical analysis showed that α-actin expression in the aortic wall was significantly decreased in the oversized groups compared with the control group (P = .002031). There were no significant differences in either the number of muscle fibers or α-actin expression among the four oversized groups.ConclusionsHistologic and immunohistochemical studies confirmed the structural disarrangement of the aortic wall after insertion of an endoprosthesis, including reduced number of muscle and elastic fibers.Clinical RelevanceBlunt aortic injury is a catastrophic event that most commonly affects the descending thoracic aorta, and it is the second most common cause of death in trauma patients. Thoracic endovascular aortic repair is increasingly being used to treat such conditions. The prostheses available at the time we conducted the present study were not specifically designed to treat thoracic aortic trauma. Furthermore, few stent grafts had been designed for use in normal or healthy aortic tissue or in young patients with acute angulation of the thoracic aorta. To our knowledge, no large study has evaluated the optimal target level of oversizing in thoracic aortas, especially for nonatherosclerotic aortas. We have conducted an experimental study in which we evaluated the biomechanical changes associated with four levels of stent graft oversizing on a nonatherosclerotic aortic wall. In the present report, we describe the histologic and immunohistochemical results of that study.

Purpose This study aimed to study morphological and renal structural changes in relation to different ischemic times and types of renal vascular pedicle clamping. Methods Sixteen pigs were divided into two groups (n = 8): Group AV - unilateral clamping of the renal artery and vein and Group A - unilateral clamping of the renal artery only, both with the contralateral kidney used as control. Serial biopsies were performed at 0, 10, 20, 30, 40, 50, 60, 70, 80, and 90 minutes after clamping. Results there is a correlation between the occurrence of renal damage as a function of time (p