Department of Bioartificial Organs, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
J Thorac Cardiovasc Surg. 2013 Mar;145(3):847-53. doi: 10.1016/j.jtcvs.2012.03.041. Epub 2012 Apr 12.
The surgical procedure for subglottic stenosis is technically challenging when the vocal cords are involved and concomitant management for glottic involvement is required. After total cricoidectomy and laryngotracheal anastomosis, T-tube placement for 3 to 6 months is recommended. Bone grafts might shorten this period. We report the histologic and endoscopic changes after total cricoidectomy with or without bone grafts in a canine model to suggest an appropriate period for T-tube placement and the necessity for bone grafts.
Ten dogs underwent total cricoidectomy and laryngotracheal anastomosis with or without bone grafts harvested from the ribs. Endoscopic examination was performed monthly, and 1 dog from both groups was humanely killed at 1, 2, 3, 6, and 12 months. The T-tube was removed before death in the dogs killed at 1, 2, and 3 months and at 3 and 6 months in those killed at 6 and 12 months, respectively.
Endoscopically, the glottic opening was in good condition in all dogs, except for 1 that had glottic stenosis. Histologically, active lymphocyte infiltration was observed in dense collagen fibers at the anastomosis at 1 month. At 2 and 3 months, fibroblasts were evident, suggesting active collagen fiber production. At 6 and 12 months, the collagen fibers had become looser. The bone grafts were intact and did not influence the surrounding tissue.
In the canine model, 6 months of T-tube placement is probably sufficient; however, 3 months of placement might not be. Additionally, no difference was found between the dogs with and without a bone graft.
当涉及声带时，声门下狭窄的手术具有挑战性，并且需要同时处理声门受累的情况。全环杓切除术和喉气管吻合术后，建议放置 T 型管 3 至 6 个月。骨移植物可能会缩短这一时期。我们在犬模型中报告了全环杓切除术和骨移植术或不骨移植术后的组织学和内镜变化，以提示放置 T 型管的适当时间和骨移植的必要性。
10 只狗接受了全环杓切除术和喉气管吻合术，其中一些狗还进行了取自肋骨的骨移植。每月进行内镜检查，每组有 1 只狗在 1、2、3、6 和 12 个月时被人道处死。在 1、2 和 3 个月以及 6 和 12 个月处死的狗中，在 1、2 和 3 个月以及 3 和 6 个月时分别取出 T 型管。
除 1 只狗出现声门狭窄外，所有狗的声门开口在镜下均状况良好。组织学上，1 个月时吻合处可见密集的胶原纤维中有活跃的淋巴细胞浸润。在 2 个月和 3 个月时，可见成纤维细胞，表明活跃的胶原纤维生成。在 6 个月和 12 个月时，胶原纤维变得更加疏松。骨移植物完整，不影响周围组织。
在犬模型中，放置 T 型管 6 个月可能是足够的；然而，3 个月的放置时间可能不够。此外，有无骨移植物的狗之间没有发现差异。
