[Preventing laryngeal anterior commissure adhesion after operation: a study in canines]

To explore the better operational methods by the laser surgery to treat diseases involving the laryngeal anterior commissure. It can excise the diseases as well as avoid anterior commissure adhesion, laryngostenosis and dyspnea after operations.

Twelve dogs were divided into 4 groups at random. There were three dogs in one group. A: excising experimental dog's anterior commissure by twice operations, the interval time was two weeks; B: excising experimental dog's anterior commissure in one time, at the same time suturing the silica gel sheet on the anterior commissure; C: excising experimental dog's anterior commissure in one time and then applying MMC on the wound of the anterior commissure; D: excising experimental dog's anterior commissure in one time, without any treatment.

All of the dog's surgery were completed successfully by laser. Four weeks later, we observed the raw surfaces. A: the neonatal membrane covered the wound, inflammatory reaction slight, we could not see obvious adhesion in the anterior commissure. B: the membrane covered the wound, appearing the dark chronic inflammation, we could see the adhesion in the anterior commissure slight. C: the membrane covered the wound, edematization, we could see the moderate adhesion in the anterior commissure. D: edematization, we could see the adhesion in the anterior commissure obviously. Four groups were all appeared hoarsenesses, the most slightly in group A, secondly in B and C, the worst in D. The analysis of vocal cord length of 4 groups, we used matched-pairs t-test, A, B, C groups' P>0.05, the vocal cord length didn't become shorter than before obviously. Group D's P<0.01, that meant the vocal cord length became shorter obviously. Between each group,we used reiterature-measurement analysis of variance (P<0.05), the change of vocal cord length had disparity in different groups. The comparison in two groups suggested that group A is the best. B and C are inferior ,but no disparity between them. The analysis of glottis area of 4 groups, as the same method above, A,B groups' P>0.05, the glottis area didn't shrink than before obviously. C and D groups' P<0.05, that meant having statistical significance and glottis area shrinked obviously. Between each group, we used reiterature-measurement analysis of variance (P>0.05), we could not think that the changes of four groups have disparity.

Excising the experimental dog's anterior commissure by laser, compared the 4 different operation methods, group A is the best method. B and C are inferior. The results are valuable in clinic when we perform operations by laser to treat the disease involving the anterior commissure.