[Ear reconstruction after rupture of postauricular expanded flap].

OBJECTIVE: To summarize the principles of ear reconstruction after rupture of postauricular expanded flap. METHODS: The rupture of the postauricular expanded flap was graded as I-IV degree. For flap rupture of I and II degree, the ear reconstruction was performed immediately with autogenous cartilage framework. For flap rupture of III degree, topical and systemic treatment should be done to relieve the redness and swelling. Then the ear reconstruction was performed. For flap rupture of IV degree, the expanded postauricular flap was smoothened. Ear reconstruction was performed 3 months later. RESULTS: There were 67 cases with flap rupture, including 43 cases as I and II degree, 17 cases as III degree and 7 cases as IV degree. Ear reconstruction with autogenous cartilage framework was performed in 43 cases, with Medpor framework in 17 cases. Flap smoothing and secondary ear reconstruction with autogenous cartilage framework was performed in 7 cases. The results were satisfactory with complications in 4 cases (7%), which resolved after treatment. Primary healing was achieved in all the patients. CONCLUSIONS: Good result could be achieved in ear reconstruction, even after flap rupture. Proper treatment should be adopted according to the rupture degree.

[Experimental research on DNA methylation profile in congenital microtia].

OBJECTIVE: To screen for abnormal methylation in CpG islands and CpG sites through whole genome of congenital microtia to identify their associated genes. To discuss the relationship between abnormal methylation level of genes and the etiology of congenital microtia. METHODS: Residual ear cartilage of 50 patients with microtia was collected with ear cartilage of 34 patients without ear malformations as control. Nimblegen CpG promoter array was chosen to screen the 28,226 CpG islands in the whole genome of both experimental and control groups. The genes with differential methylated CpG islands were selected. SpectroCHIP array was chosen to detect the methylation level of each CpG site in abnormal methyletion CpG islands of both experimental and control groups. The CpG sites with differential methylation level were selected. RESULTS: There were 36 CpG islands with differential methylated level in whole genome between experimental group and control group, among which 29 CpG islands were connected with 29 named genes. In the abnormal methylated CpG islands of COL18A1, MYH14, RBMY1A1 and ZIC3, 6 differentially methylated CpG sites were found with statistical significance. The methylation level of these 6 CpG sites in experimental group and control group were COL18A1_2_CpG_170.9783 +/- 0.0235 and 0.9526 +/- 0.0589; MYH14_CpG_170.9600 +/- 0.0414 and 0.9284 +/- 0.0655; RBMY1A1_1_CpG_3.40.9966 +/- 0.0055 and 0.9914 +/- 0.0069; RBMY1A1_1_CpG_130.9648 +/- 0.0118 and 0.9757 +/- 0.0127; ZIC3_3_CpG_150.0867 +/- 0.0212 and 0.0543 +/- 0.0399; ZIC3_2_CpG_270.3775 +/- 0.1816 and 0.472 3 +/- 0.0439. CONCLUSIONS: The DNA methylation profile of the entire genome is initially established. The abnormal methylated CpG islands of COL18A1, MYH14, RBMY1A1 and ZIC3 might be related to the pathogenesis of microtia.

Induction of the chick columella and its integration with the inner ear.

BACKGROUND: The auditory complex of the chick, like that of humans, is made of intimate and highly ordered connections between the inner ear, the middle ear, and the outer ear. Unlike mammals, the middle ear of chick has only one ossicle, known as the columella. The independent lineages of the two suggest that some mechanism must exist that ensures the connectivity between the inner ear and the columella; however, the basis of integration is not known. RESULTS: Using quail-chick chimeras, we demonstrate that columella development depends on signaling interactions. Specifically, both pharyngeal endoderm and cranial paraxial mesoderm can alter the morphology of the columella. Only a discrete region of pharyngeal endoderm exerts this patterning activity, and this region is specified by the overlying paraxial mesoderm. CONCLUSIONS: Paraxial mesoderm is also used in the induction of the inner ear, thus we propose that this overlapping source of signalling cues in both middle and inner ear development may underlie the integration of these structures.

[Sectional anatomical analysis of auricular and middle ear malformation in patients with microtia].

OBJECTIVE: To analyze the sectional anatomical features of auricular and middle ear malformation in patients with microtia so as to improve the clinical classification and the instruction of surgery. METHODS: From Jun. to Dec. 2009, 36 cases with microtia were selected in the center of auricular reconstruction in Plastic Surgery Hospital, including 22 cases of unilateral microtia and 14 cases of bilateral microtia. 22 patients with unilateral microtia were studied with the contralateral healthy ears as controls. Spiral CT was performed for high-resolution scan of the temporal bone. The coronal, sagittal and 3D reconstruction images were created with Mimic software. Several distances and degrees were measured. RESULTS: The patients were classified by Max classification. The anteroposterior diameter and the vertical diameter of tympanic cavity were (7.75 +/- 1.92) mm and (14.66 +/- 4.75) mm for type I; (6.17 +/- 2.56) mm and(14.35 +/- 5.12) mm for type II; (6.31 +/- 3.40) mm and (9.97 +/- 4.36) mm for type III (P = 0.001). The mastoid pneumatization degree for type I, II, III were 13.33%, 13.64%, 30.77% in sclerotic type, 13.33%, 18.18%, 7.69% in diploe type, 0, 9.09%, 38.46% in composite type, 73.33%, 59.09%, 23.08% in pneumatic type (chi2 = 24.11, P = 0.002). The cover of fenestra vestibuli by facial nerve was 21.43%, 47.62%, 54.55% (chi2 = 23.44, P = 0.002) for type I, II, III. There was a statistical difference between the microtia group and the control group. CONCLUSIONS: According to the Max classification, the middle ear malformation changed along the auricular malformation. The anatomical variations was complicated in type II microtia, which should be sub-classified.

[Application of bi-pedicled frontal expanded flap for cervical cicatricial contracture].

OBJECTIVE: To investigate the therapeutic effect of bi-pedicled frontal expanded flap for cervical cicatricial contracture. METHODS: Tissue expanders were implanted under frontal muscle. After expansion, the frontal flaps were designed based on bilateral superficial temporal vessels and were transferred to the neck wound. The cervical spine movement and the mento-cervical angle was measured and analyzed by SPSS16.0 and t test. RESULTS: From September 2006 to May 2010, 7 patients were treated by this method. The range of active cervical movement was improved in all direction. The mento-cervical angle decreased from (152.7 +/- 1.9) to (90.7 +/- 2.2) degrees after operation. The patients were followed up for 5 months to 3 years with satisfactory result and no contracture recurrence. CONCLUSIONS: The bi-pedicled expanded frontal flap has a reliable blood supply and is very suitable for cervical cicatricial contracture with good functional and esthetic results, leaving less morbidity at donor site.

[Application of quantitative tissue expansion in ear reconstruction].

OBJECTIVE: To explore the application of tissue expander in ear reconstruction and to deal with the complications. METHODS: 50 ml kidney-shape tissue expanders were implanted subcutaneously in the mastoid area. The drainage tube was removed 3 days after operation. The suture was removed 10 days later. Since 7 days after operation, 5 ml NS was injected into the expander every time, three times a week. The total injection volume was about 60 ml. After that, the expander was maintained for one month. RESULTS: From January 1992 to December 2006, 5,248 patients of microtia were treated with 6,252 expander. After the maintaining period, the expanded skin was thin and well-vascularized. The complication rate was 7.79%, including hematoma, malunion and infection. CONCLUSIONS: The quantitative tissue expansion is easily manipulated with few complications. It can provide hairless, thin skin with reliable blood supply for ear reconstruction.

[Fabrication and application of three-dimensional autogenous cartilage framework in auricular reconstruction].

OBJECTIVE: To explore the fabrication and application of three-dimensional autogenous cartilage framework in auricular reconstruction. METHODS: The process of fabrication of three-dimensional cartilage framework consisted of cartilage harvesting, carving and assembling the cartilage. The rib cartilage was harvested separately. The three-dimensional framework was composed of three main parts:the helix, the base and the pad, at different layer. The framework was fabricated according to the development of rib cartilage and contour and height of the reconstructed ear. RESULTS: From January 1992 to December 2006, 5,248 patients of microtia were treated with 6,252 autogenous cartilage frameworks. CONCLUSIONS: The three-dimensional framework is easily manipulated. The reconstructed ears look natural and had an erect contour. This method can effectively use the cartilage.

[Application of the remnant in repairing the reconstructed ear in microtia].

OBJECTIVE: To explore the application of the remnant in repairing the reconstructed ear in microtia. METHODS: From October 2000 to July 2006, 1,823 patients with reconstructed ear underwent the second operation for repairing. The remnants were used to reconstruct tragus, antitragus, crus of helix, concha cavum, or relax the adhesion between the reconstructed auricle and cranio wall, or insert into the reconstructed lobule or 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. RESULTS: In 1,823 cases, the tragus, antitragus and concha cavum was reconstructeded by remnant auricle in 1,180 cases; helix crus was repaired by remnant auricle in 743 cases; the wound was repaired by remnant auricle flap resulted from relaxing the adhesion between the reconstructed auricle and cranial wall in 68 cases; Subcutaneous and cartilage flap was formed and transferred in 95 cases, and among them the flap was transferred under the basement of the frame to restore the cranio-auricular angle in 77 cases and was transferred to the preauricular subcutaneous to correct the facial local depression in 18 cases; the skin flap was formed by remnant auricle to repair the lobule in 37 cases. All flaps survived completely. The appearance of reconstructed ear was satisfied. CONCLUSION: The remnant is very useful in repairing the reconstructed ear in microtia. It should be preserved propriately in auricular reconstruction.

[Surgical treatment and etiological analysis of polyotia].

OBJECTIVE: To explore the surgical treatment and pathologic mechanism of polyotia. METHODS: The operative methods for polyotia were flexible. The main procedures were aimed at the remodeling of tragus with the redundant tissue. Tissue transplantation was used to correct the depression deformity. Compound auricular tissue transplantation and Z-plasty were used for correction of the malformation at the posterior part of polyotia. RESULTS: From 2003 to 2008, 9 patients with polyotia were treated. The tragus was reconstructed after resection of redundant tissue. The depression deformity was corrected with tissue infilling in 6 cases. The compound auricular tissue transplantation was performed in 4 cases. Z-plasty at the lower ear lobe was performed in 2 cases. The appearance and the location of the reconstructed ears looked symmetric to the healthy ear. CONCLUSIONS: Natural and symmetric appearance of reconstructed ear can be achieved in polyotia. The abnormal migration of neural crest cell might be the pathologic mechanism of polyotia.

[Study of methylation of promoter of EYA1 gene in microtia].

OBJECTIVE: To explore the methylation of CpG islands in promoter of eye absent gene 1 (EYA1) in microtia. METHODS: The methylation of CpG islands in EYA1 gene in 64 microtias and 36 healthy controls were measured using the technique of matrix-assisted laser desorption/ionization-time of flight. RESULTS: The methylation of CpG_Unit3 and CpG_Unit5 of EYA1 gene in microtia were 0.09258 +/- 0.033846 and 0.0922 +/- 0.02379, respectively, which were significantly lower than those in control. CONCLUSIONS: Hypomethylation in microtia may be related to the pathogenesis of the disease.

[Design and application of the expanded transposition flaps in the treatment of cheek skin defects].

OBJECTIVE: To introduce the design and application of the expanded transposition skin flap in the treatment of cheek skin defects. METHODS: The expanded transposition flaps were divided into three types: the regular expanded transposition flap (ERT flap), the expanded transposition-advancement-transposition flap (TAT flap) and the expanded rotation-advancement-transposition flap (RAT flap). 135 cases of cheek skin defects resulted from hemangioma, scar and naevi were treated with these three types of flaps. Delay surgery was needed when the ratio of length to width was bigger than 2 : 1. RESULTS: There were 139 expanded transposition flaps, including 17 ERT flaps, 69 TAT flaps, 53 RAT flaps. Blood supply disturbance was happened at the end of the flaps in 6 cases, including 2 ERT flaps and 4 other flaps. Other flaps had no complication. The results were satisfactory. CONCLUSIONS: The expanded transposition skin flap is a reliable method to repair the cheek skin defect. The preoperative flap design is very important for successful reconstruction.

[Repairing traumatic partial helical defect with postauricular tube flap].

OBJECTIVE: To investigate the effect of postauricular tube flap for repairing traumatic partial helical defect. METHODS: The tube flaps were designed according to the site and size of helical defects. The length of tube flaps was 1.2 - 1.5 times as the length of the defects. The length-to-width ratio of tube flap was 3 - 4:1. The procedures required three stages for completion: (1) fabrication of tube flap; (2) 2 - 3 weeks later, division of one pedicle and insetting the flap; (3) 2 - 3 weeks later, complete division of pedicle and repairing the defects. RESULTS: From January 1998 to June 2006, 47 cases of traumatic partial helical defects were treated with postauricular tube flaps. All the tube flaps survived completely with no vascular disturbance, infection or necrosis. The patients were followed up for 2 months to five years with satisfactory results. CONCLUSIONS: Postauricular tube flap is a reliable and simple procedure for traumatic partial helical defects with good cosmetic result and less donor site morbidity.

[Clinical application of three methods for total ear reconstruction].

OBJECTIVE: To investigate the indication and results of three methods for total ear reconstruction. METHODS: 960 cases of total ear defect were treated with skin expansion and autogenous rib cartilage framework (n = 786), or skin expansion and Medpor framework (n = 150), or ear prosthesis (n = 24). The indication and results of the three methods were analysed. RESULTS: Good cosmetic results were achieved with all three methods. Autogenous rib cartilage framework was suitable for patients under 30 years old with unaffected skin at mastoid region. Medpor framework was good for grown-up, especially over 30 years old, or with mild infection at mastoid region. Patients with severe skin injury at mastoid region or unwilling to accept surgery should choose ear prosthesis. CONCLUSIONS: Satisfactory results can be achieved with suitable methods for total ear reconstruction.

[Biomechanical properties of the costal cartilage and its significance in the timing of ear reconstruction].

OBJECTIVE: To investigate the age-related change in biomechanical properties of the costal cartilage and its relevance to the timing of ear reconstruction with costal cartilage framework. METHODS: The patients of 5 to 25 years old were divided into three groups according to their age. The biomechanical properties of costal cartilage harvested from these patients during ear reconstruction were tested, including stree-strain relationship, stress relaxation and creep, tensile strength. All the results were analyzed statistically. RESULTS: The costal cartilage from children group had the best biomechanical properties, while the costal cartilage from the adolescent group had the worst. The difference had a statistically significance (P < 0.05). CONCLUSIONS: The biomechanical properties of costal cartilage are age-related. So it is recommended that ear reconstruction with costal cartilage framework should be performed in childhood when the costal cartilage has the best biomechanical properties.

[Histologic study and type II collagen expression in the rib cartilage of patients at different age].

OBJECTIVE: To study the difference of histologic examination and type II collagen expression in the rib cartilage of patients at different age. METHODS: The patients were divided into three groups, as children group (5 to 10 years old), teenager group (11 to 17 years old), and adult group (18 to 29 years old). Histologic examination of rib cartilage and quantitative analysis of type II collagen with immunohistochemical stain were carried out in the three groups. Motic Med 6.0 A system was used to quantitate immunohistochemical image through measurement of mean photodensity. The results were statistically analyzed. RESULTS: Among the three groups, the children's rib cartilage had the most blood vessels, the most chondrocytes, well-distributed stain of matrixes, and the type II collagen was expressed actively and highest in photodensity. The rib cartilage of teenager group had less blood vessels, unhomogeny distributed stain of matrixes, the enlarged and separated cartilage lacunae. The rib cartilage in adult group showed the least blood vessels, the least chondrocytes, the hyalinization of perichondrium, the most deposition of calcium salt, and the type II collagen was expressed at the lowest level in photodensity. Statistical analysis showed significant differences among the three groups (P < 0.01). CONCLUSIONS: Histologic structure in human rib cartilage changes during the aging process and the type II collagen is decreased with the increase of age.

[Clinical study of chest contour deformity after harvesting of costal cartilage for total ear reconstruction].

OBJECTIVE: To investigate the chest contour deformities after harvesting of costal cartilage for total ear reconstruction, so as to prevent donor site morbidity. METHODS: 107 cases of microtia who underwent ear reconstruction with costal cartilage during the period from 1994 to 2003, were retrospectively studied. Both the chest depression deformity and the costal arch deformity were evaluated. The possible related factors to the chest contour deformities were analyzed statistically with Stata software. RESULTS: The incidence of chest depression was 54.55% (48/88), including 35 cases of mild depression (39.77%) and 13 cases of severe depression (14.77% ). The incidence of costal arch deformity was 52.77% (46/88), including 33 cases of mild deformity (37.50%) and 13 cases of severe deformity (14.77%). The incidence of both deformities was significantly different at different age (P < 0.01), but not at different follow-up period (P = 0.294 and P = 0.225, respectively). Gender was related to the incidence of chest depression (P < 0.01), but not to the costal arch contour deformity (P = 0.619). Comparing resection of the 6th and 7th rib cartilage with resection of 7th and 8th rib cartilage, the incidence of costal arch deformity was significantly different (P < 0.01), but the incidence of depression deformity was not (P = 0.657). CONCLUSIONS: The incidence of chest deformities increases with early operation time (< 13 years old). The male patients have higher incidence of depression deformity than female. The arch deformity is higher when the 6th and 7th rib cartilage were resected. The follow-up period is not related to the chest deformities.

[Clinical significance of vascular distribution type of the expanded skin in the mastoid region in congenital microtia].

OBJECTIVE: To classify the blood vessel distribution of the expanded skin in the mastoid region and its relevance to reasonable and reliable design of the expanded flap for auricular reconstruction in congenital microtia. METHODS: The blood vessel distribution of the expanded skin in the mastoid region was observed by light permeation test. The expanded flaps with different ratio of length to width were designed according to their blood vessel distribution types. RESULTS: The vascular distribution of the expanded skin in 403 cases was divided into five types. All the flaps survived completely. CONCLUSIONS: The blood vessel distribution type of the expanded skin in mastoid region has great significance for the design of post-auricular expanded flap in auricular reconstruction.

[The experimental study on the effect of CDMP-1 on proliferation of residual ear chondrocytes of microtia cultured in vitro].

OBJECTIVE: To investigate the alternation of biological characteristics of residual ear chondrocytes when proliferating in vitro, and study the effects of CDMP-1 on proliferation and differentiation of residual ear chondrocytes. METHODS: Residual ear chondrocytes were cultured in vitro. Then we observed the effect of CDMP-1 on differentiation by immunohistochemistry of collagen type II and dyeing with toluidine blue, investigated proliferation effects of CDMP-1 by method of MIT, and analysis cell cycle changes by flow cytometry. RESULTS: The quantity of GAG gradually decreased along with the increase of the doubling time of chondrocytes in vitro. The quantity of chondrocytes with positive expression of collagen type II were significantly more in the experimental group used with CDMP-1 than the contrast. And the most efficient concentration of CDMP-1 was 100 ng/ml. CONCLUSIONS: CDMP-1 had a good effect on proliferating and could maintain morphology of the residual ear chondrocytes of microtia cultured in vitro.

Satisfactory surgical option for congenital microtia with defects of external auditory meatus (EAM) and middle ear.

CONCLUSIONS: Improved appearance and hearing and increased efficiency are achievable for congenital microbia with defects of external auditory meatus (EAM) and middle ear. First the site of the external auditory meatus (EAM) orifice must be located according to the results of the temporal CT scan, then the auricle can be reconstructed employing the three-stage method. At the third stage, the EAM and middle ear can be reconstructed at the same time. OBJECTIVE: To select the best approach for reconstruction of congenital microtia with defects of the EAM and middle ear. PATIENTS AND METHODS: This study analyzed 498 cases (528 ears) of auricle reconstruction by the three-stage method and 77 cases (91 ears operation/120 ears) of EAM and middle ear reconstruction. RESULTS: For auricular reconstructions, the effects of reconstructed auricles were classified into four grades according to their structure verisimilitude and the bilateral symmetry. The majority of patients/families were satisfied. For 52 ears with normal movement of stapes, reconstructions of EAM and middle ear improved hearing by 15-50 dB, but long-term improvement was not ideal. In bilateral patients, 20 of 24 ears with reconstructed EAMs exhibited relapse of stenosis or atresia. For patients whose EAMs were reconstructed first, scar developed around the orifice and affected the skin flap and later auricle reconstruction, while reconstructing the auricle first sometimes resulted in the location of the EAM orifice deviating from an ideal position.