[An experimental study of mucociliary clearance of trachea reconstructed with free jejunum].

OBJECTIVE: To investigate tracheal mucociliary transport change after reconstructed with free jejunum. METHODS: Twelve canine models of extensive circumferential tracheal defects reconstructed with revascularized jejuno combined with Ni-Ti alloy mesh tube were established. Every canine model was marked in cervical skin projecting the lower resected margin of trachea lumen and was injected 50% barium sulfate mucilage as a tracer into the trachea lumen under bronchoscopy. Record the time from tracer injected into trachea lumen to its arriving glottis (mucociliary transit time, MTT) and the length from tracer injected into trachea lumen to glottis (mucociliary transport length, MTL). Mucociliary transit rate (MTR), as MTL/ MTT, was calculated. The same procedure was performed at preoperative and postoperative 7th day, 1 month, 3 months and 6 months. RESULTS: There were statistical significance between preoperative MTR and 1 month postoperative MTR (P < 0.05). There were no differences between preoperative MTR and postoperative MTR at the 7th day, 1 month, 3 months and 6 months. There were also no differences between postoperative MTR at the 7th day and 1 month, 3 months and 6 months. CONCLUSION: In new tracheal tract reconstructed with free jejunum, MTR becomes normal at 3 months postoperatively.

[Experimental reconstruction of the canine trachea with shape-memory titanium-nickel alloy stent coupled with free jejunal graft].

OBJECTIVE: To explore the reconstruction method of extensive circumferential tracheal defects longer than 6.0 cm and evaluate the influence on pulmonary function from jejunal secretion. METHODS: Jejunal secretion model without extraneous nerve were established. 10 mongrel dogs were randomly divided into two groups. In group A, the nude stent made by shape-memory titanium-nickel alloy (SMA stent) was placed in the interior of the intestinal lumen. In group B, the SMA stent with silicone membrane was placed in the interior of the intestinal lumen. The secretion and histological chance of these jejunal were observed regularly. The cervical tracheal segment (6.5 cm) was replaced by the intestinal graft. In group C (6 mongrel dogs), the nude stent made by SMA stent was placed in the interior of the intestinal lumen. In group D (6 mongrel dogs and 6 Beagle dogs), the SMA stent with silicone membrane was placed in the interior of the intestinal lumen, the nude "C-shaped" SMA stent was placed out of the intestinal lumen, and the silicone stent was removed the fourth week after operation. In group C and group D, endoscopic and histological examinations were performed between the first week and eighth month. RESULTS: The secretory peak of Jejunal secretion model without extraneous nerve ranged from the first day to seventh day after operation. The jejunal secretion reduced gradually from 7th days after operation. The jejunal secretion remained steady after postoperative two months. In group C, endoscopic examination showed heavy proliferation of granulation in the tracheo-intestinal anastomosis. 4 dogs died between seventh day to second month. In group D, one dog died from ileus third month after operation. The other all survived operation. Gentle pneumonia happened to some dogs during 1-2 months after operation by X-ray examination. No one died of pneumonia result from hypersecretion. CONCLUSIONS: Reconstruction of the canine trachea with SMA stent with silicone membrane placed in the interior of the intestinal lumen together with the nude "C-shaped" SMA stent placed out of the intestinal lumen achieve satisfactory effect, the reconstructed trachea remain unblocked and this method of tracheal reconstruction may be relatively perfect and be expected for clinical application in future. The jejunal secretion didn't have severe influence on pulmonary function of experimental canine and couldn't cause experimental canine death.

[Modified type I thyroplasty for treating unilateral vocal cord paralysis].

OBJECTIVE: To explore a new surgical approach for treating unilateral vocal cord paralysis. METHODS: Five cases of unilateral vocal cord paralysis due to various causes were treated with modified type I thyroplasty. Laryngostroboscopy and electroglottography were performed before and after the operations. RESULTS: The vocal cords were shifted very close to the median line in all the 5 cases postoperatively as shown by laryngostroboscopy and electroglottography. Complete closure of the glottis was achieved. The patients had almost normal results of electroglottography, and the vocal sound nearly recovered normal or was significantly improved. CONCLUSION: Modified type I thyroplasty is effective, safe and easy in treating unilateral vocal cord paralysis.