Experimental study of replacement of an esophageal segment with an nitinol alloy composite artificial esophagus / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the feasibility of a segment thoracic esophagus replaced by using a nitinol alloy composite artificial esophagus.</p><p><b>METHODS</b>A nitinol alloy composite artificial esophagus was made of a nitinol tube coated with a silicone membrane with a dacron flange 1 cm proximal to each end. There were ten pigs for the models of experimental animal. The models of experimental animal were established by excised a segment of 7 cm long thoracic esophagus and replaced with the graft. In accordance with the different anastomosis connective way 10 pigs were divided into group I and group II, every group had 5 pigs. In group I monolayer end-to-end anastomosis was used with this prosthesis. In group II monolayer end-to-end anastomosis was used with this prosthesis and above the site of anastomosis adding dacron strip fixed. After operation the operate animals were observed for eating and health. Esophagography and flexible esophagoscopy were performed once a month at the first, second, and third postoperatively month. Three pigs of the grafted prostheses sloughed out spontaneously at different postoperatively period were killed for autopsy and pathologic examination of the neoesophagus.</p><p><b>RESULTS</b>All pigs had no leakage at the site of anastomosis and survived over 6 months. The longest survival was 20 months. Seven of 10 pigs the grafted prostheses sloughed out spontaneously at 2 to 6 months after the operation (4 in group I and 3 in group II). The grafted prostheses sloughed out spontaneously less than 3 months after operation, marked neoesophageal stenosis in the grafted portion was recognized (3 in group I). They displayed serious difficulty in eating. But the prostheses sloughed out spontaneously more than 3 months after operation, neoesophageal stenosis was increased slightly and the stenosis was only temporary and gradually resolved. (1 in group I, 3 in group II) They lived in good health and without difficulty in eating. Three of 10 pigs the grafted prosthesis still stayed in the grafted place over 10 months (1 in group I, 2 in group II). The neoesophageal had no stenosis. They were perfectly well in eating.</p><p><b>CONCLUSIONS</b>A segment excised pig esophagus replaced with a nitinol alloy composite artificial esophagus is feasible and takes a better result.</p>

The value of three-phase pulmonary helical CT in diagnosing peripheral pulmonary cancer (diameter

<p><b>OBJECTIVE</b>To evaluate the value of three-phase pulmonary helical CT in diagnosing peripheral pulmonary cancer (diameter </= 3 cm).</p><p><b>METHODS</b>Serial single-slice dynamic scans were obtained with helical CT before and after injection of 100 ml contrast material in 60 patients with solitary pulmonary nodules (SPNs, diameter <or= 3 cm). The three-phase pulmonary helical CT was established by analyzing enhancement feature of thoracic aorta and pulmonary artery, and then the enhancement feature of three-phase pulmonary helical CT was analyzed.</p><p><b>RESULTS</b>The delayed times of three-phase pulmonary helical CT were pulmonary artery phase (15 second), bronchial artery phase (36 second), equilibrium phase (90 second) respectively. The prevalence model of density change for three-phase pulmonary helical CT: no enhancement, marked enhancement, moderate-enhancement in pulmonary cancer; slight or moderate-enhancement, marked-enhancement, marked-enhancement in inflammatory nodules; no enhancement or light-enhancement in tuberculoma and metastatic nodules. The enhanced branch and small spot vessels were demonstrated by bronchial artery phase in 82.9% of pulmonary cancer nodules.</p><p><b>CONCLUSION</b>The three-phase pulmonary helical CT could reflect the enhancement feature, blood supply of bronchial artery in peripheral pulmonary cancer (diameter </= 3 cm), it is helpful in early diagnosis and differentiation.</p>