A novel method for engineering autologous non-thrombogenic in situ tissue-engineered blood vessels for arteriovenous grafting.

The durability of prosthetic arteriovenous (AV) grafts for hemodialysis access is low, predominantly due to stenotic lesions in the venous outflow tract and infectious complications. Tissue engineered blood vessels (TEBVs) might offer a tailor-made autologous alternative for prosthetic grafts. We have designed a method in which TEBVs are grown in vivo, by utilizing the foreign body response to subcutaneously implanted polymeric rods in goats, resulting in the formation of an autologous fibrocellular tissue capsule (TC). One month after implantation, the polymeric rod is extracted, whereupon TCs (length 6 cm, diameter 6.8 mm) were grafted as arteriovenous conduit between the carotid artery and jugular vein of the same goats. At time of grafting, the TCs were shown to have sufficient mechanical strength in terms of bursting pressure (2382 ±â€¯129 mmHg), and suture retention strength (SRS: 1.97 ±â€¯0.49 N). The AV grafts were harvested at 1 or 2 months after grafting. In an ex vivo whole blood perfusion system, the lumen of the vascular grafts was shown to be less thrombogenic compared to the initial TCs and ePTFE grafts. At 8 weeks after grafting, the entire graft was covered with an endothelial layer and abundant elastin expression was present throughout the graft. Patency at 1 and 2 months was comparable with ePTFE AV-grafts. In conclusion, we demonstrate the remodeling capacity of cellularized in vivo engineered TEBVs, and their potential as autologous alternative for prosthetic vascular grafts.

Results from craniocaudal carotid body tumor resection: should it be the standard surgical approach?

OBJECTIVES: To evaluate results after carotid body tumor (CBT) surgery using a novel dissection technique. METHODS: A retrospective analysis of all operated CBT in the last 6 years was carried out and results were compared with the current literature and our previous series, which reported another 111 cases operated on until 2005. RESULTS: Forty-five CBTs were removed in 41 (56% hereditary cases) patients (seven Shamblin I, 22 II, and 16 III). There were no cases of permanent cranial nerve injury or stroke. These pre- and postoperative results compare favorably with our previous series and are superior to, generally smaller, studies reported in the contemporary literature. CONCLUSIONS: This large series of surgically-treated CBTs supports craniocaudal dissection as the surgical technique of choice as it limits blood loss and facilitates safe CBT resection.