计算机辅助构建气管软骨环并行气管前壁缺损修复实验研究

目的探讨利用人工材料在计算机辅助下体外构建气管软骨环进行颈段气管缺损修复的可行性。方法用β-磷酸三钙(β-TCP)材料制造出气管环。12只成年杂种犬,雌犬4只,雄犬8只,犬龄约2岁,体质量11~13kg。随机均分为2组。行气管前壁3~5环全层缺损造模(缺损2cm×5cm),在气管切除部位形成一直径约2cm、长约5cm的皮管。实验组利用计算机辅助构建气管软骨环阴模,以β-TCP材料制作的内径约2cm的2个C形气管软骨环支架置于人工皮管外侧,外侧以肌肉覆盖,逐层缝合关闭术腔。对照组以相同方法行气管前壁全层缺损造模,并形成与实验组相同的人工皮管,但皮管外面不置β-TCP构建的软骨环支架。动物饲养至8周时处死取材,行大体解剖、纤维喉镜、CT及常规组织学检查。结果术后所有动物伤口局部未见明显感染征象。对照组1只皮下严重气肿,当日死亡;大体解剖可见修复部分气管前壁塌陷,管腔狭小;其余动物均存活至8周,术后1周出现气喘,术后2周出现进食呕吐及颈部活动受限;纤维喉镜检查,修复部位气管前壁已出现塌陷,有明显的反常呼吸运动。实验组动物均成活良好,未见上述症状。纤维喉镜检查:重建气道通畅。CT检查:植入物位置良好。组织学检查,支架材料已与周围组织融合为一体,组织已长入支架材料的孔隙中。结论实验应用计算机辅助技术,使修复支架制作达到个体化,β-TCP材料具有良好的生物相容性,且应用计算机辅助技术依个体需要快速塑型,能较好地修复气管缺损。

Experimental study on computer-aided construction of tracheal rings for anterior tracheal defect repair

Objective To explore the feasibility of computer-aided construction of tracheal rings using artificial materials for repairing cervical tracheal defect. Methods β-tricalcium phosphate（β-TCP） material was used to construct tracheal rings. Twelve adult mongrel dogs（8 males and 4 females, aged 2-year-old, with body weight of 11- 13 kg） were randomly divided into 2 groups,experimental group and control group. The anterior 3- 5 ring tracheal defect model（2 cm × 5 cm defect） was made to form a skin tube with diameter of about 2 cm and length of 5 cm in the tracheal resection site. In experimental group, two C-shaped tracheal rings with inside diameter about 2 cm were produced by computer-aided construction using β-TCP, placed outside of the artificial skin tube,and stitched with the skin tube by suspension suture. The cavity was closed by layer by layer suture and covered with lateral muscle.The control group underwent the same operation procedure except that without β-TCP cartilage ring was placed outside the skin tube. The animals were sacrificed after 8 weeks, and fiber laryngoscopy, CT and conventional histological examination were conducted. Results None of the animals showed infection after operation. In control group, one animal died at the operation day due to severe subcutaneous emphysema, and gross anatomic observation showed that the repaired anterior part of the trachea collapsed and the lumen narrowed. All the other animals in control group survived 8 weeks post operation, which showed asthma at 1 week after operation, and vomiting after eating with limited neck mobility at 2 weeks after operation. Fiber laryngoscopy showed that the repaired part of anterior wall was collapsed with obviously abnormal breathing exercise. All the animals in experimental group survived 8 weeks without any symptoms. Fiber laryngoscopy showed smooth reconstructed airways and CT examination showed good implantation position. Histological examination showed that the β-TCP scaffolds were integrated well with the