Tiam Mana Saffari

73 OBJECTIVE EVALUATION OF ANGIOGENESIS USING MICRO CT AND PHOTOGRAPHY 4 This group was considered the gold standard for nerve repair. Rats survived for either 12 or 16 weeks. At the time of the sacrifice, the nerve vasculature was preserved to obtain the vascular volume and vascular surface area measurements. Surgical procedure After anesthesia in an isoflurane chamber, rats were shaved, prepped and positioned in the nosecone to maintain anesthesia throughout the procedure. Preoperatively the following were administrated subcutaneously; infection prophylaxis provided by Enrofloxacin (Baytril, Bayer, Germany, 10mg/kg), 5 ml of NaCl 0.9% solution to prevent dehydration and Buprenorphine SR (Buprenorphine SR-LAB, ZooPharm pharmacy, 0.6mg/kg) for pain control. During surgery, body temperature was maintained at 37°C with a heating pad. The sciatic nerve was fully exposed proximally from the inferior margin of the piriformis muscle to approximately 5 mm distal to the bifurcation, under an operating microscope (Zeiss OpMi 6, Carl Zeiss Surgica, Oberkochen, Germany). A 10mm segment of the sciatic nerve was excised by sharp transection with microsurgical scissors. The nerve graft was reversed and reconstructed with six 10-0 nylon (Ethilon, Ethicon Inc., Sommerville, NJ, USA), epineural interrupted sutures on either side of the anastomosis. Wounds were closed in layers, approximating muscle with two 5-0 absorbable interrupted sutures (5-0 Vicryl Rapide, Ethicon Inc., Sommerville, NJ, USA). The skin was closed subcutaneously, using the same suture. Postoperatively, the rats were kept warmwith towels. The rats were observed weekly until completion of the experiment. Perfusion of contrast Twelve and 16 weeks postoperatively, rats were sacrificed. Access for aortic infusion catheter placement was achieved via the abdomen. A large midline incision was made in the abdomen to expose the aorta and vena cava. A small retractor was used to retract the digestive organs providing stable exposure of the aorta and vena cava throughout the experiment. The fat surrounding the thoracic aorta and vena cava was cleaned using cotton tip applicators taking care not to harm the vascular structures. The thoracic aorta and vena cava were ligated proximally with a 5-0 Vicryl suture (5-0 Vicryl Rapide, Ethicon Inc., Sommerville, NJ, USA) which was kept long to act as grip