ĐẶT VẤN ĐỀ Thiểu sản vành tai (TSVT) là bệnh lý bẩm sinh do sự phát triển bất thường của vành tai trong thời kỳ bào thai với các mức độ khác nhau, từ nhẹ là bất thường một phần cấu trúc của vành tai đến nặng là hoàn toàn không có vành tai. TSVT làm ảnh hưởng lớn đến vấn đề thẩm mỹ thậm chí có thể dẫn đến sự mặc cảm do bị người xung quanh kỳ thị, xa lánh. Do vậy những trẻ này cần được chỉnh hình vành tai sớm để giúp trẻ hòa nhập và nâng cao chất lượng cuộc sống. Hiện tại trên thế giới có các phương pháp tạo hình vành tai chủ yếu là: tạo hình bằng sụn sườn tự thân, tạo hình bằng vật liệu nhân tạo hoặc lắp vành tai giả. Trong đó tạo hình vành tai bằng sụn sườn tự thân vẫn là phương pháp tin cậy, mang lại kết quả thẩm mỹ lâu dài. Tuy nhiên ở Việt nam vẫn chưa có nhiều đề tài nghiên cứu về phương pháp này. Vì vậy chúng tôi thực hiện nghiên cứu đề tài “Nghiên cứu kết quả phẫu thuật tạo hình thiểu sản vành tai nặng theo kỹ thuật Nagata” này nhằm mục tiêu: Đánh giá kết quả phẫu thuật tạo hình thiểu sản vành tai nặng theo kỹ thuật Nagata 1. Tính cấp thiết Ở bệnh viện Tai Mũi Họng trung ương hàng ngày đều có tiếp nhận BN TSVT đến khám, tư vấn và mong muốn được phẫu thuật vì vậy nhu cầu THVT là rất lớn. Trong các phương pháp THVT hiện nay trên thế giới thì tạo hình bằng vật liệu nhân tạo mới bắt đầu tiến hành ở Việt Nam và lắp tai giả chưa được tiến hành ở Việt Nam. Tuy nhiên 2 phương pháp này giá thành còn cao so với người dân Việt Nam và cũng có nhiều nhược điểm. Chỉ còn phương pháp tạo hình bằng sụn sườn tự thân là thích hợp nhất với ưu điểm: sụn sườn tự thân nên không có nguy cơ thải ghép, kết quả phẫu thuật ổn định lâu dài, tính thẩm mỹ tương đối cao. Chúng tôi lựa chọn kỹ thuật Nagata vì kỹ thuật này có những ưu điểm: thời gian và số lần phẫu thuật được rút ngắn, vành tai tạo hình trông tự nhiên hơn. Vì THVT là 1 kỹ thuật vô cùng phức tạp và tinh tế, đòi hỏi PTV được đào tạo bài bản và được phẫu thuật thường xuyên. Chúng tôi cũng hy vọng rằng khi tiến hành đề tài này trước hết giúp các bác sỹ Việt Nam có thể làm chủ được kỹ thuật, phẫu thuật một cách thường xuyên liên tục để hoàn thiện kỹ thuật, giảm bớt biến chứng, giúp BN có kết quả tốt về mặt thẩm mỹ, cải thiện tâm lý cũng như sự tự tin trong cuộc sống. 2. Những đóng góp mới của luận án - Đã mô tả được đặc điểm lâm sàng của bệnh nhân thiểu sản vành tai mức độ nặng và một số bệnh lí liên quan. - Ứng dụng được phương pháp tạo hình vành tai theo kỹ thuật Nagata có cải biên (sử dụng cân sau tai thay cho cân thái dương đỉnh) cho bệnh nhân thiểu sản vành tai mức độ nặng nên phẫu thuật phù hợp với người Việt nam, đạt kết quả cao và ít biến chứng. 3. Bố cục của luận án - Luận án được trình bày 111 trang bao gồm: đặt vấn đề 02 trang, tổng quan 30 trang, đối tượng và phương pháp nghiên cứu 21 trang, kết quả nghiên cứu 27 trang, bàn luận 27 trang, kết luận 1 trang, kiến nghị 1 trang - Luận án có 33 bảng, 03 biểu đồ, 12 hình, gồm 89 tài liệu tham khảo được xếp theo thứ tự xuất hiện trong luận án.
1 INTRODUCTION Microtia is a congenital condition caused by the abnormal development of the auricle during pregnancy to varying degrees, from mildly abnormal structural part of the ear to severe Microtia greatly affects the aesthetic issue, which can even lead to inferiority complex due to being stigmatized and shunned by people around them Therefore, these children need to get their ears corrected early to help them integrate and improve their quality of life Currently in the world, there are some methods of ear reconstruction: forming by autologous rib cartilage, shaping by artificial materials or installing artificial ear canal In that, forming ear flaps with rib cartilage itself is still a reliable method, bringing long-lasting aesthetic results However, in Vietnam, there are still not many researches on this method Therefore, we carry out this research project "Research on the results of ear reconstruction surgery by Nagata technique" to: Evaluate the results of ear reconstruction surgery by Nagata technique The urgency At the ENT hospital, every day there are microtia patients to visit, consult and desire surgery so the need for ear reconstruction is great In the current methods in the world, the making of artificial materials has just begun in Vietnam and prosthetic implant fitting has not been conducted in Vietnam However, these two methods are still expensive compared to Vietnamese people and also have many disadvantages Only the method of using rib cartilage itself is most appropriate with the advantage: the rib cartilage itself should not have a risk of graft rejection, the results of long-term stable surgery, relatively high aesthetic We chose the Nagata technique because it has the advantages: the time and the number of surgeries are shortened, the reconstructed ear looks more natural Because ear reconstruction is an extremely complex and sophisticated technique, requires a well-trained and regularly operated surgeon We also hope that when conducting this topic, it will firstly help Vietnamese doctors to master the technique and surgery on a regular basis to improve the technique, reduce complications and help patients to have good results in terms of aesthetics, improved psychology as well as confidence in life New contributions of the thesis - Describe the clinical characteristics of patients with severe microtia and accompanied malformations - Apply the modified Nagata tehnique (using the posterior auricular fascia instead of the temporoparietal fascia flap) for patients with microtia, so the surgery is suitable for Vietnamese people, achieve high results and few complications The layout of the thesis: - The thesis is presented with 110 pages including: 02 page introduction, 31 pages overview, 20-page research objects and methods, 27-page research results, 27-page discussions, 1-page conclusions and 1-page proposal - The thesis has 33 tables, 03 charts, 12 pictures, including 89 references arranged in the order of appearance in the thesis CHAPTER 1: BACKGROUND 1.1 Embryology and anatomy of the auricle 1.1.1 Embryology The outer ear consists of the auricle and ear canal, developing from the mesenchymal layer of the first and second pharyngeal arch The auricle is made up of auricular hillocks of His At the 5th week of pregnancy, hillocks arise from the mandibular arch (His 1,2,3) and the remaining hillocks from the hyoid arch (His 4,5,6) opposite of the first pharyngeal arch Around the 12th week, auricular hillocks converge together to create a defined structure of the ear The aurilce is in the same shape as an adult by about the 18th week By years it reaches 85% of adult size and the ear cartilage is almost complete by years of age, although it continues to grow until about years old, it reaches adult size Microtia occurs when there is an abnormal problem during the development of the auricle in the embryonic period 1.1.2 Anatomy 1.1.2.1 Appearance: includes components: the helix, antihelix, tragus, antitragus, scapha, triangular fossa, concha and lobule 1.1.3 Auricular anthropometry The ears are located on either side of the head, related to the temporomandibular joint and the parotid gland in the front, the mastoid bone and the upper temporal region The auricle is like leaves with the free part opening behind, creating with the mastoid surface an angle of about 20 - 30º (auricular- mastoid angle) - Limit of normal auricle + Above: not higher than straight line crossing eyebrows + Lower: not lower than the straight line across the nose + The longitudinal axis of the auricle: is the straight line connecting the highest peak of the auricle to the lowest point of the lobule, this line is usually created with a vertical angle of 15 - 20º and parallel to the axis of the nose bridge + The anterior ear axis corresponds to the posterior edge of the branch on the mandibule - Size of ears: average length of about 65mm long, 35 mm wide, with length / width ratio ≈ 2/1 1.2 Pathology of microtia 1.2.1 Epidemiological characteristics - The incidence of microtia: ranges from 0.83 to 4.34 / 10,000 newborns, common among Asians, Pacific Islanders and Hispanic people (Spain and Portugal) - Microtia is predominant in men, right ear is more common than left ear - Microtia may be isolated, or in combination with other abnormalities, or may be part of the syndrome: OAVS system (OAVS: Oculo-Auriculo-Vertebral Spectrum) with the most classic manifestation is congenital Goldenhar syndrome or Klippel-Feil deformities 1.2.2 Morphology of microtia 1.2.2.1 Morphological characteristics About 70-90% of cases of microtia occur on one side with the prominence in men and more often in the right ear than the left Bilateral microtia: relatively rare with the ratio of about 0.05 ‰ 1.2.2.2 Classification of microtia: There are many ways to classify microtia but the most popular classification is Marx's (1926) He divided microtia into three categories: + Type I: the ear is smaller than normal and still has most of its normal structures (still with external ear canal) + Type II: the ear is missing 1-2 anatomical units of the ear canal (without earlobe or helix), the external ear canal is blocked or narrow 4 + Type III: the ear structure is only a small part of peanut,, without external ear canal Later, Marx added Type IV: anotia: no auricle In this thesis, we classify III and IV as severe microtia which require total ear reconstruction 1.3 Ear reconstruction surgery - Using autologous rib cartilage: featured with techniques of Brent and Nagata - Using artificial rib cartilage (MEDPOR or polyethylene) - Prosthetic implant 1.3.1 Ear reconstruction with autologous rib cartilage: a gold standard surgery 1.3.1.1 Age of the patient Brent thinks the age suitable for surgery is years old According to Nagata, the appropriate age is 10 years or older, or when the chest circumference> 60 cm 1.3.1.2 Four- stage technique of Brent: - Stage 1: Haversting of rib cartilage, constructing the framework, and inserting the framework in the pocket subcutaneously at the reconstructed ear location - Stage 2: Lobule transposition - Stage 3: Elevation of the reconstructed ear with a skin graft to create the auriculocephalic sulcus - Stage 4: Tragal construction, conchal excavation, and simultaneous contralateral otoplasty 1.3.1.3 Two- stage technique of Nagata: Stage 1: harvesting of the costal cartilages, fabrication of the threedimensional cartilage framework (3-D frame) and the grafting of the 3D frame to its proper anatomical location + Step 1: Creating an auricle template (similar to Brent technique) + Step 2: Haversting the ipsilateral rib cartilage Perichondrium is preserved to avoid chest deformity after surgery The cartilage pieces are sewn together with a special type of steel thread + Step 3: Implanting the framework in the pocket subcutaneously at the reconstructed ear location + Step 4: Lobule transposition and tragus reconstruction 5 Stage 2: At least months after stage - Get the additional piece of cartilage (banked under the thoracic skin during the first stage) - Take a free flap from groin with an appropriate size - Elevate the framework - Place the semilunar cartilage, fixed by the posterior auricular fascia - Using a thickness skin graft to cover posterior auricular area * Advantages: The time and the number of surgeries are shortened The reconstructed ears look more natural * Defect: The risk of lobule necrosis is higher (due to the lack of blood vessels) The chest is weak (due to the large number of cartilage taken) The risk of hair loss on the scalp 1.3.1.4 Symptoms - Complications at the chest * Early complications - Perforation of the pleura: - Pneumothorax: - Hematoma: caused by occlusion, slipping drainage in the chest * Late complications - Thoracic deformity: - Bad scars, keloid scars, hypertrophic scars: - Complications at the ear * Early complications - Necrosis of skin flap covered with framework - Hematoma, condensation: caused by occlusion, closed drainage - Infection: - Cartilage inflammation: causing necrosis, deformed framework , affecting aesthetic results – Ischemia when lobule transposition * Late complications - Bad scars, hypertrophic scars, keloid scars - Changes in the morphology of the cartilage framework: + Errors in the position (right) of the ear, + Changes in skin color + Change in the size of the framework + Loss of the anatomy details CHAPTER 2: SUBJECTS AND METHODS OF THE STUDY 2.1 Subjects 2.1.1 Selection criteria: - Patients diagnosed with congenital severe microtia (type III, IV according to Marx) underwent ear reconstruction by Nagata technique at ENT Hospital - Patient has full participation in stages of surgery - Having complete medical records - Follow- up after 2nd stage at least months - Agree to join the research 2.1.2 Exclusion criteria - Patient had surgery at another hospital; Patients were operated without Nagata technique- Patient was not followed-up at least once after nd stage of surgery for months Patients not agree to participate in the research 2.1.3 Sample size: Because microtia is a rare disease, we selected a convenient sample size In fact, in the years from 2016 to 2019, we screened all 32 eligible patients for the study In which, 15 patients were retrospective and 17 patients were prospective 2.2 Methods 2.2.1 Study design: clinical intervention study, before-after control 2.2.3 Research location: Esthetic and Plastic Surgery Department ENT Hospital Research period: within years from 2016 to 2019 2.2.4 The main evaluation parameters 2.2.4.1 Before surgery: age and gender - Family history: - The position of microtia: or sides, left or right - External ear canal: narrow or completely blocked - Accompanied malformations: - Features of normal ear: Length, width, the distance between helix-lateral canthus, the distance of ear from mastoid bone, the auricular- mastoid angle - Number of surgeries: - Hospital stay of each time: - Time between stages: 2.2.4.2 After surgery - Early and late complications of st stage at the chest, at the location of the reconstructed ear - Managing complications - Aesthetic results of the ear in various aspects: were evaluated after follow-up times: times after stage 1, times after stage 2; Each visit is at least months apart + Location: position, the distance between helix-lateral canthus, the distance helix- mastoid, the auricular- mastoid angle, the ear axis + Size: length, width + Shape (13 anatomical details) + Other characteristics: ear thickness, skin color, unwanted hair, scar - Satisfaction level of the patient: 2.3 Steps to proceed 2.3.1 Designing samples of research records, collecting data Develop a sample medical record to collect data - Select patients according to the set criteria - Explain the patient agrees to participate in the study and sign a commitment to agree to participate in the study - Condut patient information collection according to the sample case: - Administrative part: recording full name, age, gender, address, phone contact, hospital registration number, research record number to contact and evaluate after surgery - For retrospective patients: retest according to the information in the sample medical records at the beginning of the study All retrospective patients have only completed stage of the surgery, so we proceeded to conduct research at stage - For prospective patients: pre-surgery clinical examination: fully record in detail the morphological characteristics of the microtia ear 2.3.2 Planning the surgery: - Use a piece of X-ray film to draw hightlights key structure of the normal ear: For patients with bilateral microtia, we use a sample ear that matches the face of the patient (sample ears have sizes: big, medium and small) - Locate the reconstructed ear: - Draw the shape and size of the ear canal to prepare for reconstruct at the position of the microtia ear, mark with an indelible marker pen or pump methylene blue pole at the top and bottom of the ear, the ear axis - Locate the donor site at the ipsilateral chest - Photographing patients before surgery 2.3.3 Ear reconstruction by Nagata: includes stages: 2.3.3.1 Stage 1: Create a 3D cartilage framework with the ipsilateral rib cartilage, lobule transposition and tragus reconstruction Step 1: Take rib cartilage: Often use rib cartilage 6, 7, 8, to sculpting cartilage framework Specifically: take a block of rib cartilage 6, to create the basic frame, take the whole rib cartilage 8.9 to the adjacent section with the rib, preserve the perichondrium Bury the excess cartilage pieces under the chest skin for nd stage Sculpte the rib cartilage into the details of the normal ear, stitching to fix the details with steel thread Step 3: Create a skin pocket: Redefine the ear landmarks: ear axis, highest and lowest points Create skin pockets by undermining postauricular scalp area to a specified size, not too wide, not too tight Control the bleeding carefully Step 4: Implant the cartilage framework into the skin pocket: Implant the cartilage framework beneath the skin corresponding to the location of the reconstructed ear that was located in step Turn the earlobes into position and reconstruct the tragus Step 5: Closed drainage - close the skin pocket - wound bandage: Put closed drains, apply antibiotic- light compress Follow up after surgery: + At the chest: Bleeding, hematoma: drainage usually withdrawn after 24 hours; pneumothorax + At the location of the ear: Keep negative pressure of drains Evaluate skin color: pink or hematoma, purple, black, necrotic Observe if the main anatomical details are clear, whether the new ear in right place 2.3.3.2 Stage 2: Elevate the cartilage framework: after st stage at least months Take a piece of cartilage waiting at st stage Take a thickness skin graft in the groin area Cut the skin behind on the cartilage framework 5mm from the atrial edge of the cartilage, all the way to the scales behind the ears Elevate the cartilage framework up and forward, reposition the ear if needed Place the semilunar cartilage padding on the cartilage frame, cover and fix by posterior auricular fascia, collating so that it is proportional to the opposite side Fixed stitching of skin grafts on the back of the framework Fixation with bolster Follow up after surgery: - After surgery, patients are given antibiotics, analgesic, anti- imflamation - Examining to detect and handle complications: infections, skin flap, regular observation of flap color - Bolster is removed after 5-7 days 9 2.3.4 The corrective surgery After 2nd stage surgery, depending on the surgical results on the shape, size and position of the reconstructed ear, there may be corrective surgery for perfection: - Correction of hypertrophic or keloid scars - Edit unclear anatomical details, misalignment - Edit the auricular- mastoid angle 2.3.4.1 Evaluate general results after surgery - Assessing the results of st stage surgery: with the following criteria: + At the chest: points: for each of the following criteria: Bleeding requires intervention after surgery; drainage of pleura, necrotic infection with necrotic, non-healing scar point: for each of the following criteria: Bleeding must intervene during surgery; pleural suture, edema, no infection points: for each criterion: No bleeding; no punctured pleura, good scars + At the ear: point for each criterion: Closed drainage is lost, open to be sewn or continuous aspiration; hematoma; infected surgical incisions, scarred necrosis; skin flap necrosis > 1cm; chondritis cartilage destruction point for each criterion: leaked drains must be applied with antibiotic grease; Hematoma requires no intervention; wound without infection, no necrosis; skin flap necrosis 10mm; auricular- mastoid angle > 20o; distance between helix- mastoid> 10mm; distance between helix- lateral canthus > 10mm point for each criterion: Length, width 5-10mm; ear axis less deviated; auricular- mastoid angle 10 ͦ -20o; distance between helixmastoid 5- 10mm; distance between helix- lateral canthus 5- 10mm points for each of the following criteria: Length, width 55 cm 4.1.2 Sex All studies of microtia is male predomiant disease except for one study by Zhu (2000) that found no difference between the sexes, it is not explained in detail 4.1.4 Location Microtia is mainly on the right, accounting for 62.5%, only 34.4% has left ear and patient has on both sides This is also consistent with the clinical characteristics of microtia more commonly on the right than on the left According to Ly Xuan Quang, among 38 patients with 50% had right ear, 47.4% had left ear and there was patient with both ears, according to Brent, a total of 1200 cases was 58.2% had right ear , 32.4% had left ear and 9.4% had both ears, according to Kawanabe this rate is 65.2% and 34.8 respectively However, the reason why microtia is more common on the right is that no studies have mentioned it 4.1.6 The malformation and accompanied syndrome There were 19 patients with hemifacial microsomia, accounting for 57.6%, higher than Brent's study of 36.5%, Zhang's study was 44% Thus, the majority of patients with hemifacial microsomia This problem poses the need plastic surgegy so that the face is symmetric so that the reconstructed ear can become more balanced The surgery helps to symmetry the face for 18 better results This is the expectation of many parents as well as patients, it also affects the level of satisfaction of the patient 4.1.7 Normal ear charateristics Our results are relatively consistent with Vietnamese results in terms of length and width There are currently no studies evaluating the angle auricular- mastoid, the distance between helix- lateral canthus, the distance auricular- mastoid 4.2 Reconstructed ear results 4.2.1 Number of surgeries The average number of surgeries per patient is 2.75 Most of the following surgeries are corrected for ear details or fistula surgery Although the Nagata technique consists of only stages of surgery, in fact it is only major surgeries In addition, after surgeries, there will be a number of small corrective surgeries According to Constatine, the average number of surgeries is 4.88 times, higher than our study According to the summary at the International Ear Reconstruction Congress in 2007, 61% of surgeon operated times, 29% of surgeon operated twice for ear reconstruction 4.2.3 The time between stages Over time we have mastered the technique and the first patients to be completely operated by Vietnamese surgeons who have had stage surgery are months According to Ly Xuan Quang, 71.8% of patients had the nd stage after 6-12 months According to the th International Ear Reconstruction Congress, 71% of patients had the 2nd stage after 6-12 months 4.2.4 Complications of surgery 4.2.4.1 Complications at the chest: - Early complications: There are cases of pleural perforation, of which most are holes avoids hematoma and congestion so it is necessary to close the skin incision Three out of 32 patients (9.4%) had a mild infection, which was characterized by a red, inflamed ear ring Patients who are exchanging or adding antibiotics are stable According to Firmin (2010) the infection rate was 6/930 cases (0.65%), the cause is usually from the outer ear canal caused by Pseudomonas bacteria According to Long (2013) this rate is 0.9% However, in our study, only patient had skin flap necrosis (3.0%), According to Firmin (1998), the rate was higher, 13.9% According to Long (2013), the rate is lower than 0.16% Learning from this complication, we see an important role in creating skin pockets at the location of the microtia Skin pockets should be removed not too thick to avoid seeing the anatomical details but not too thin, which will lead to malnutrition and skin necrosis - Late complications: After stages, patients had hypertropic scars and patients with keloid scars According to Cho (2007), out of 125 patients had keloids in the reconstructed ear So we can see the bad scarring rate of our study is much higher 20 4.2.4.3 Complications at the inguinal skin site - Early complications: No patients - Late complication: the rate of bad scars is relatively high although patients not have keloid scars Causes: the inguinal skin is the movement part of the body that makes it difficult for the scar to stabilize during the healing process and can easily lead to bad scars In addition, this may be related to racial factors, such as Wolfram and Yotsuyanagi's assessment of the risk of bad scars and keloids in which colored people are at higher risk than whites 4.2.5 Reconstructed ear characteristics The average length and width of the reconstructed ear are smaller than the normal side, but the difference is negligible, about 1-2mm The average angle of the auricular- mastoid is 16.7º, which is about 3-4º smaller than the average angle of the normal ear In addition, there are patients with different angles from 10-20º The cause of the reduction of the auricular- mastoid angle over time may be due to: - The semilunar cartilage is not thick enough to elevate the ear - The high rate of bad scars also causes the skin flap shrink over time To solve this problem we have options: - If the right side of the ear is large, the shape of the ear is not too small, you can proceed to adjust the shape of the good side to create a balance - Enhance the angle of the ear by strengthening the extra cartilage placed behind the cartilage framework 4.2.6 Compare these indicators with healthy ears through examinations 4.2.6.1 Difference in ear length compared to healthy side: In our study, 60.6% of cases had the difference