Clinical Application Of The Remnant Auricle Of Microtia In Auricular Reconstruction

Objective:1.To classify the remnant auricle of microtia and describe the application of them in every stage of auricular reconstruction.2.To evaluate the difference between the effect of reconstructed auricle and the microtia type and the difference between the blood supply of expanded flap and two different treatment methods to larger DegreeⅠremnant auricle with higher location.To explore the value and necessity of applying remnant auricle in auricular reconstruction.Methods:1.Classifying the remnant auricle of 1930 ears of 1823 cases between 2000 and 2006 in external ear center of Plastic Surgical Hospital of Medical Sciences by comparing it's location and size with contralateral or normal ear.2.All cases were treated by expanded auricular reconstruction method.Different application was designed according to the remnant auricle type:In expander's implanting stage,the upper part of DegreeⅠremnant auricle with higher location was separated from the cranio wall.In auricular reconstructing,the remnant auricle of DegreeⅠmicrotia was utilized sufficiently combining with the rib cartilage frame.According to the shape and location of remnant auricle of DegreeⅢand three types of DegreeⅡ,different lobular flap was designed and transferred.In reconstructed auricle's repairing,the remained remnant auricle was used to reconstruct tragus,antitragus,crus of helix, concha cavtum;to relax the adhesion between the reconstructed auricle and cranio wall;to cover the wound surface which was resulted from repairing the reconstructed auricule.The skin tag of remnant auricle was transferred to plump the reconstructed lobule.The vestigal cartilage remnant was transferred under the basement of the costal cartilage frame to restore the cranio-auricular angle or to the preauricular subcutaneous to correct the facial local depression.3.To follow-up 273 cases more than 1 year postoperatively and evaluate their reconstructed auricle excluding the impacts induced by investigators and post-operative complications.To analyze the difference of reconstructed auricle effect in different types of microtia and the difference in two methods to manipulate the bigger DegreeⅠremnant auricle with higher location.Result:1.The remnant auricle of congenital microtia was classified into 3 degrees and the DegreeⅡwas classified into 3 types.2.In 1823 cases,in DegreeⅠ167 cases,the flap formed by remnant auricle encapsulated the frame with expanded flap.Among these cases,the upper part of remnant auricle was separated from the cranio wall in 40 cases;In DegreeⅡ1553 cases,the lobules of 1227 cases were transferred to the normal location,every lobular flap survived,no necrosis or other blood supply problem.In 1129 cases,the tragus,antitragus and concha cavtum was reconstructeded by remnant auricle.In 743 cases,helix crus flap was formed. Subcutaneous and cartilage flap was formed and transferred in 56 cases,and among them the flap was transferred under the basement of the frame to restore the cranio-auricular angle in 38 cases and was transferred to the preauricular subcutaneous to correct the facial local depression in 18 cases;In DegreeⅢ103 cases, the reconstructed tragus was formed in 51 cases,the skin flap was formed to repair the lobule in 37 cases,the cartilage flap was formed in 39 cases.All flaps talked above survived completely.3.The effect of reconstructed auricle followed-up was satisfied. The reconstructed auricle score of DegreeⅠ,ⅡA,ⅡB,ⅡC,Ⅲmicrotia was 7.02 0.91,6.51±0.97,6.50±1.12,6.47±1.08,and 5.68±0.99 by turns.Both the reconstructed auricle scores of DegreeⅠand DegreeⅢshowed significant statistic difference relative to the score of every type of DegreeⅡ(t=2.1374＞t_0.05,66,P＜0.05; t=2.290＞t_0.05,200,P＜0.05,and t=2.521＞t_0.05,40,P＜0.05,t=3.2399＞t_0.05,60,P＜0.05; t=3.2656＞t_0.05,200,P＜0.05,and t=2.410＞t_0.05,38,P＜0.05).The scores of every two types of DegreeⅡshowed no significant statistic difference(P＞0.05).The blood supply of expanded flap formed by two methods to upper part of bigger DegreeⅠwith higher location showed significant statistic diggerence(P＜0.05).Conclusion:1.Classification of remnant auricle provided the objective basis for clinical application.2.The effect was satisfied when the remnant auricle was used to reconstruct and repair the auricle in congenital microtia.3.The more the remnant auricle can be used,the better the postoperative effect was.The effect of every type of DegreeⅡwas same.The blood supply of expanded flap will be ensured by separating the upper part of bigger DegreeⅠramnant auricle from cranio wall.4.The remnant auricle of microtia is the third key factor following the cartilage frame and skin in auricular reconstruction.