Evaluation of mastoid volume and dimensions in unilateral microtia patients: retrospective study using High Resolution Computed Tomography (HRCT).

OBJECTIVE: The aim of this study is to evaluate mastoid volume and dimensions in patients with unilateral microtia using High-Resolution Computed Tomography (HRCT) to enhance the precision of reconstructive surgical planning. METHODS: A retrospective analysis of HRCT mastoid scans from patients with unilateral microtia was carried out at Cipto Mangunkusumo General Hospital between May 2020 and August 2022. Parameters such as mastoid volume, height, and surface area were measured at the ear canal, Superior Semicircular Canal (SCC), and lateral SCC levels. RESULTS: The analysis revealed statistically significant decreases in median mastoid air cell volume and mastoid bone volume in the affected ears compared to contralateral ears (p =  0.0312 and p =  0.02, respectively). Additionally, decreased mastoid height and surface areas at the ear canal and superior SCC levels were identified in affected ears (p <  0.05). CONCLUSIONS: Patients with unilateral microtia have diminished mastoid bone volumetric parameters and dimensions on the affected side. These findings offer critical data for surgeons in preoperative planning, enabling the selection of appropriate reconstructive techniques and providing comprehensive patient counselling. LEVEL OF EVIDENCE: Level 4.

Reconstrucción auricular con implantes mastoideos utilizando el sistema Novaloc / Implant supported auricular reconstruction using the Novaloc system

La microtia es un padecimiento congénito de etiología desconocida que se puede presentar asociado a síndromes, su frecuencia es mayor en hombres, tiene predilección por el oído derecho. Se han propuesto distintas alternativas de tratamiento tanto estéticas como funcionales que disminuyan riesgos y aumenten la calidad de vida de los pacientes. Entre los tratamientos más comunes se encuentra el injerto costocondral, siendo una alternativa viable, aunque de mayor riesgo y que puede necesitar varios procedimientos quirúrgicos con el fin de lograr el mejor resultado estético; por lo mismo, uno de los tratamientos más realizados actualmente, es la reconstrucción auricular con implantes osteointegrados que se colocan en la región mastoidea y soportan una prótesis auricular. Se presenta el caso de un paciente masculino quien fue rehabilitado con implantes mastoideos ostoeintegrados para reconstrucción auricular implantosoportada. Las prótesis implantosoportadas reducen la necesidad de realizar cirugías correctivas y posibilitan la buena higiene de la prótesis al ser ésta removible, pero sin sacrificar su estabilidad. Los sistemas más utilizados son los mismos que se emplean en sobredentaduras, ya que el diseño del aditamento transmucoso, se adapta perfectamente al grosor del epitelio en la región mastoidea, por lo que es una excelente alternativa de tratamiento (AU)

Microtia is a congenital condition of unknown etiology that can occur associated with syndromes. Its frequency is greater in men and has a predilection for the right ear. Different treatment alternatives, both aesthetic and functional, have been proposed that reduce risks and increase the quality of life of patients. Among the most common treatments can be found the costochondral graft being a good alternative although greater risk of failure and the probability of several surgeries to get the best aesthetic result. Because of that one of the most used treatments is the placement of osseointegrated implants that can hold a prosthetic ear. Here is a case of a male patient who was rehabilitated with osseointegrated mastoid implants for ear reconstruction. Implant-supported prostheses significantly reduce the number of surgeries that must be performed and is a good option to maintain excellent hygiene as the prosthetic ear is removable, without compromising stability. The most common system is the same as those used in overdentures since the design of the transmucosal attachment fits perfectly to the thickness of epithelium in mastoid region (AU)

Clinical profiling of pediatric microtia patients: A cross-sectional analysis at a leading pediatric hospital in Ecuador (2015-2022).

BACKGROUND: Microtia is a frequent congenital deformity of the pinna, often with hearing loss. This study reviews the clinical profiles of microtia pediatric patients treated at a referral hospital in Quito, Ecuador, from 2015 to 2022. METHODS: A cross-sectional descriptive study was carried out based on the analysis of medical records of pediatric patients with microtia treated between January 2015 and December 2022 at the Hospital Pediátrico Baca Ortiz in Quito, Ecuador. Descriptive statistics were used, and the Chi-square test assessed associations between categorical variables. RESULTS: Of the 235 patients evaluated, 59.6% were male, 83.4% lived at high altitudes (2500-3500 m), and 19.1% had a family history of microtia. Grade III microtia was diagnosed in 63.8%, predominantly on the right side. Nearly all (99.1%) had hearing loss. Other anatomical alterations were observed in 27.7%, primarily the preauricular appendage. Bone vibrator implantation was a common treatment for 24.3%. Altitude did not show a significant correlation with microtia characteristics. CONCLUSIONS: Most patients had grade III microtia with associated hearing loss. Despite the high prevalence at elevated altitudes, no significant altitude-disease correlation was found. The study highlights the need for further research on microtia in regions like Ecuador.

Remaining microtia tissue as a source for 3D bioprinted elastic cartilage tissue constructs, potential use for surgical microtia reconstruction.

The absence of ears in children is a global problem. An implant made of costal cartilage is the standard procedure for ear reconstruction; however, side effects such as pneumothorax, loss of thoracic cage shape, and respiratory complications have been documented. Three-dimensional (3D) printing allows the generation of biocompatible scaffolds that mimic the shape, mechanical strength, and architecture of the native extracellular matrix necessary to promote new elastic cartilage formation. We report the potential use of a 3D-bioprinted poly-ε-caprolactone (3D-PCL) auricle-shaped framework seeded with remaining human microtia chondrocytes for the development of elastic cartilage for autologous microtia ear reconstruction. An in vivo assay of the neo-tissue formed revealed the generation of a 3D pinna-shaped neo-tissue, and confirmed the formation of elastic cartilage by the presence of type II collagen and elastin with histological features and a protein composition consistent with normal elastic cartilage. According to our results, a combination of 3D-PCL auricle frameworks and autologous microtia remnant tissue generates a suitable pinna structure for autologous ear reconstruction.

A Hollow Tridimensional Silicone Template for Microtia Reconstruction and Postoperative Scar Compression.

Microtia poses a great challenge in auricular reconstruction, due to a great number of anatomical details on the anterior aspect, and its tridimensional shape. Numerous techniques have been described in an attempt to optimize results. We have designed a hollow tridimensional silicon template to serve as an intrasurgical guide for ear's anatomy, size and projection, according to the normal side, which allows better results of auricular reconstruction. It also can be used as a customized post-operative compression method. We believe it could be a valuable tool for microtia reconstruction surgery. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Efectividad de la reconstrucción de la oreja con cartílago costal en el tratamiento de microtias / Effectiveness of Auricle Reconstruction with Costal Cartilage for the Treatment of Microtias

Introducción: La reconstrucción de la oreja en la actualidad es un problema difícil de solucionar. Se han propuesto varias técnicas quirúrgicas y solo las que se basan en el uso de cartílago costal autólogo son las que se aceptan a nivel mundial. Objetivo: Evaluar la efectividad de la técnica de reconstrucción del pabellón auricular descrita por Burt Brent. Métodos: Se realizó un estudio cuantitativo con diseño descriptivo de corte transversal con 41 pacientes que presentaron microtia congénita o perdida adquirida de la oreja; a quienes se les realizó reconstrucción auricular con cartílago costal autólogo tratados en el Hospital "William Soler", el Centro de Investigaciones Médico-Quirúrgica y Clínica Central "Cira García" en el Servicio de Cirugía Plástica desde 1994 hasta 2019. Se describió y se documentó la técnica empleada descrita por Burt Brent. Se utilizó una escala de 10 puntos que se basó en la anatomía auricular normal para la valoración de los resultados. Resultados: Se encontraron 32 pacientes portadores de microtia congénitas (78,04 %) y 9 pérdidas traumáticas (21,95 %), predominó el sexo femenino (56,09 %). La incidencia fue mayor en el lado derecho (68,75 %) en pacientes con microtia congénita. En el 95 % de los casos se alcanzaron resultados favorables y satisfactorios. Conclusiones: La reconstrucción del pabellón auricular requiere el empleo de un fragmento de cartílago costal de suficiente tamaño, forma y proyección. La clave consiste en esculpir un marco cartilaginoso de la oreja y mantener estos detalles a través de la piel lo más semejante a la oreja normal. Para un resultado satisfactorio se requiere una alta especialización.

Introduction: Auricle reconstruction is, nowadays, a difficult problem to solve. Several surgical techniques have been proposed and only those based on the use of autologous costal cartilage are accepted worldwide. Objective: To evaluate the effectiveness of the auricle reconstruction technique described by Burt Brent. Methods: A quantitative study with a cross-sectional descriptive design was carried out with 41 patients who presented congenital microtia or acquired loss of the ear and who were performed auricle reconstruction with autologous costal cartilage in the plastic surgery service at Hospital "William Soler", Centro de Investigaciones Médico-Quirúrgicas and Clínica Central "Cira García", from 1994 to 2019. The used technique described by Burt Brent was, in turn, described and documented. A 10-point scale based on the normal atrial anatomy was used to assess the outcomes. Results: Thirty-two patients with congenital microtia (78.04 %) and nine traumatic losses (21.95 %) were found, with a predominance of the female sex (56.09 %). The incidence was higher on the right side (68.75 %) in patients with congenital microtia. Favorable and satisfactory outcomes were achieved in 95 % of cases. Conclusions: Auricle reconstruction requires the use of a costal cartilage piece of enough size, shape and projection. The key is to sculpt a cartilaginous framework of the ear and to maintain these details through the skin as close as possible to the normal ear. A high level of specialization is required for a satisfactory outcome.

The Enigmatic Etiology of Oculo-Auriculo-Vertebral Spectrum (OAVS): An Exploratory Gene Variant Interaction Approach in Candidate Genes.

The clinical diagnosis of oculo-auriculo-vertebral spectrum (OAVS) is established when microtia is present in association with hemifacial hypoplasia (HH) and/or ocular, vertebral, and/or renal malformations. Genetic and non-genetic factors have been associated with microtia/OAVS. Although the etiology remains unknown in most patients, some cases may have an autosomal dominant, autosomal recessive, or multifactorial inheritance. Among the possible genetic factors, gene−gene interactions may play important roles in the etiology of complex diseases, but the literature lacks related reports in OAVS patients. Therefore, we performed a gene−variant interaction analysis within five microtia/OAVS candidate genes (HOXA2, TCOF1, SALL1, EYA1 and TBX1) in 49 unrelated OAVS Mexican patients (25 familial and 24 sporadic cases). A statistically significant intergenic interaction (p-value < 0.001) was identified between variants p.(Pro1099Arg) TCOF1 (rs1136103) and p.(Leu858=) SALL1 (rs1965024). This intergenic interaction may suggest that the products of these genes could participate in pathways related to craniofacial alterations, such as the retinoic acid (RA) pathway. The absence of clearly pathogenic variants in any of the analyzed genes does not support a monogenic etiology for microtia/OAVS involving these genes in our patients. Our findings could suggest that in addition to high-throughput genomic approaches, future gene−gene interaction analyses could contribute to improving our understanding of the etiology of microtia/OAVS.

Proposed clinical approach and imaging studies in families with oculo-auriculo-vertebral spectrum to assess variable expressivity.

A diagnosis of oculo-auriculo-vertebral spectrum (OAVS) is established when microtia is present in association with hemifacial hypoplasia (HH) and/or ocular, vertebral, and/or renal malformations. There is no consensus on which imaging studies should be used to rule out variable expressivity and distinguish "sporadic" from "familial" patients. This observational and descriptive study was performed in a Mexican population of 51 patients (32 males, 19 females, 0-18 years old) with microtia/OAVS, and their available parents. A clinical history, genealogy, and physical examination were obtained from all included patients, as were a computed tomography (CT) scan of the ear, audiological evaluation, orthopantomography, complete spine radiography, and renal ultrasound. The same approach was completed in their available parents (51 mothers and 40 fathers), excluding the CT scan and audiological evaluation. By genealogy, 53% of patients were classified as "sporadic"; of the "familial" patients, at least 79.1% had suggestion of a multifactorial inheritance. In the available parents, orthopantomography, complete spine X-ray, and renal ultrasound identified the following OAVS-related manifestations: HH (16.2%, n = 14/86), vertebral alterations (10.9%, n = 10/91), and renal anomalies (2.2%, n = 2/90). Our evaluation of the parents allowed three patients to be reclassified from "sporadic" to "familial" (5.8%, n = 3/51). Our proposed clinical and imaging approach allowed the identification of variable expressivity that more clearly distinguished between "sporadic" and "familial" OAVS patients, which is of utmost importance in providing proper genetic counseling to these families.

Macrostomia congênita associada à microtia unilateral: um Relato de Caso / Congenital macrostomia associated with unilateral microtia: a case report

A macrostomia congênita, também denominada fissura facial transversa, horizontal ou lateral, constitui 1,5% de todas as fissuras. A expressão clínica variável envolve desde uma forma discreta até casos graves com malformações desfigurantes. Deformidades da orelha externa podem estar presentes, desde excesso de pele até ausência do pavilhão. A macrostomia congênita deve ser submetida a uma investigação sistemática clínica e de imagem para definir o âmbito das anomalias, uma vez que a doença é rara, complexa e manifesta-se fenotipicamente de maneiras distintas. Este presente artigo relata um caso de macrostomia congênita associada à microtia unilateral.

Congenital macrostomia, also called transverse, horizontal, or lateral facial cleft, constitutes 1.5% of all clefts. The variable clinical expression ranges from mild to severe cases with disfiguring malformations. External ear deformities can be present, from excess skin to the absence of the pinna. Congenital macrostomia must be submitted to a systematic clinical and imaging investigation to define the scope of the anomalies, since the disease is rare, complex and manifests itself phenotypically in different ways. This article reports a case of congenital macrostomia associated with unilateral microtia.

Frequency Modulation System and Bone Conduction Hearing Aid: Electroacoustic Verification.

Introduction A protocol has not yet been developed to perform electroacoustic measurements and behavioral tests to fit the frequency modulation (FM) system in bone conduction hearing aid (BCHA) users. Electroacoustic verification, with "FM transparency" achieved, ensures user audibility of FM transmitter and hearing aid signals. Objective To propose and validate a protocol for electroacoustic verification of the FM system coupled to the BCHA. Method Twenty-four sets of FM system and BCHA were submitted to electroacoustic verification, using a receiver and a plastic adapter to connect the BCHA to a 2cc coupler in the hearing instrument analyzer. The measurements were performed in the acoustic box, at 65 dB sound pressure level (SPL), with International Speech Test Signal (ISTS), first to the BCHA microphone and then to the FM system microphone, to determine the transparency, in which equivalent inputs for both microphones result in equivalent outputs. The FM gain or volume has been adjusted to try to gain transparency for the outputs of the two input devices. Results Transparency was achieved for all sets evaluated, but in some combinations, adjustments to the FM receiver gain over the manufacturer's default setting were required. Conclusion The proposed protocol proved to be effective for the electroacoustic verification of the FM system coupled to the BCHA.

One-Year Follow-Up in Children with Conductive Hearing Loss Using ADHEAR.

BACKGROUND: The ADHEAR™ system (MED-EL, Innsbruck, Austria) is a nonsurgical bone conduction device (BCD) to treat conductive hearing loss (CHL) and single-sided deafness. In contrast to the nonsurgical alternatives on headbands or spectacle frames, the audio processor of ADHEAR is placed retroauricularly on an adhesive adapter. The published evidence on the performance of this system is limited to studies with a trial period of 2-8 weeks. OBJECTIVE: This study assesses audiological and subjective outcomes over a period of 12 months, on patients with congenital aural atresia (CAA) using the ADHEAR hearing system. METHOD: Fifteen children (mean age: 9.4 ± 4 years; range: 5-16 years) diagnosed with CAA (7 uni/8 bilateral) were included in this prospective, observational, repeated-measures study. Each subject used ADHEAR for 1 year, and the performance was evaluated after 1, 6, and 12 months. Free-field audiometry and speech discrimination tests were performed, and hearing-, general health- and device-specific questionnaires were used. RESULTS: The unaided sound field threshold improved from an average PTA4 of 63.6 ± 3.4 dB HL to an aided average PTA4 of 29.3 ± 3.0 dB HL after 1 month of device use. The word recognition score (WRS) improved from an average of 27.9 ± 15.9% unaided to an aided average WRS of 91.3 ± 4.4% (p = 0.0003) after 1 month, 92.0 ± 4.1% (p = 0.0002) after 6 months, and 92.7 ± 5.3% (p < 0.0001) after 12 months using the ADHEAR system compared to the unaided condition for all 3 time points. The improvements in the speech in noise at 1, 6, and 12 months were as well consistent over time. The average improvement at the signal to noise ratio (SNR) of +5 dB was 58% and 53% at the SNR of +0 dB. No complications were reported, and all patients continued to use the ADHEAR after the study end. The questionnaire results revealed high user satisfaction and an average wearing time of 12 h per day. CONCLUSION: This 12-month trial of the nonsurgical adhesive BCD in CAA patients showed sufficient and reliable audiological and subjective outcomes, long wearing time, and high acceptance. The ADHEAR can be considered a suitable option to treat children with CAA for the given indication, without the drawbacks of nonsurgical devices that use pressure for retention of the audio processor or the costs and possible complications involved with a surgical alternative.

Craniofacial microsomia: Reflections on diagnosis and severity assessment based on a series of cases.

This study aims to discuss diagnostic criteria and severity assessment for craniofacial microsomia (CFM). A series of 61 patients with diverse CFM phenotypes had their clinical data collected by experienced dysmorphologists using a single protocol. Genetic abnormalities were searched through karyotype and chromosomal microarray analysis. Sex ratio, prenatal risk factors, and recurrence rate corroborated the literature. Despite the wide variability of clinical findings, ear disruption was universal. Eight patients were assigned as syndromic, four of whom had demonstrable genetic alterations. The majority of patients (67.2%) fulfilled four known diagnostic criteria, while 9.8% fulfilled one of them. Data strengthened disruptions of the ear and deafness as a semiotically valuable sign in CFM. Facial impairment should consider asymmetry as a mild expression of microsomia. Spinal and cardiac anomalies, microcephaly, and developmental delay were prevalent among extra craniofacial features and should be screened before planning treatment and follow up. The severity index was able to recognize the less and the most affected patients. However, it was not useful to support therapeutic decisions and prognosis in the clinical scenario due to syndromic and non-syndromic phenotypes overlapping. These issues make contemporary the debate on diagnostic methods and disease severity assessment for CFM. They also impact care and etiopathogenetic studies.

Lattice Boltzmann simulation of swelling of an implant for microtia manufactured with IPN hydrogel.

The swelling characteristics of an implant for microtia treatment manufactured with IPN hydrogel was achieved using a three-dimensional lattice Boltzmann model. Dimensionless units of length and mass were employed. Comparisons between computational data and experimental values obtained by an adsorption isotherm test of a hydrogel implant immersed in Ringer's solution at a constant temperature of 310.15 K achieve coefficients of determination between 0.98782 and 0.99669. The results demonstrate that the thickness of the sample has a great impact on the time required to achieve thermodynamic equilibrium. The method presented here is suitable to simulate the swelling of hydrogels of arbitrary geometries.

Congenital Aural Atresia prevalence in the Argentinian population.

INTRODUCTION: Congenital Aural Atresia (CAA) or microtia is a malformation that results in esthetic and functional problems. There is little information on prevalence, considering that Latin American is the most affected region in the world. OBJECTIVE: To determine the prevalence of microtia, considering the different ethnical structure of the population. METHODS: A retrospective analysis was performed of the clinical reports of newborn infants (public hospitals) in three different regions. RESULTS: The incidence of CAA in Argentina was 1 case per 7500 new births (i.e. 1.3/10,000). Marked differences were found per geographical area. The means were calculated per year by bilateral parametric estimation, according to the ethnical origins of the population. In the Caucasoid area: 02.47/10,000 (±1.2), in the Mestizo area: 03.99/10,000 (±0.0) and finally in the Amerindian area: 20.93/10,000 (±0.1). CONCLUSION: This study shows different incidences according to the demographic features of the population from 1.90/10,000 to 20.9/10,000. This data indicates that CAA is associated with a genetic problem (ethnic differences).

Cartilla de malformaciones craneofaciales congénitas: orientación e información para padres con hijos con microtia / Cartilla de malformaciones craneofaciales congénitas / Congenital craniofacial malformation card: guidance and information for parents with children with microtia

Las malformaciones congénitas pueden acarrear problemas emocionales tanto para la familia como para el paciente que tiene algún tipo de malformación congénita craneofacial, debido a factores psicosociales que intervienen en el afrontamiento de dicha patología, pues el nacimiento de un hijo con malformación implica para los padres y familiares cuidados especiales, interrogantes acerca del futuro, incertidumbre en cuanto a lo relacional y todo aquello que pueda generar frustración al paciente y a la familia. Así que es importante poder acompañar el proceso interdisciplinar, el rol del psicólogo es guiar al paciente y a su familia para afrontar y comprender que pasa y así lograr una exitosa rehabilitación y adaptación.

Characterization of pediatric microtia cartilage: a reservoir of chondrocytes for auricular reconstruction using tissue engineering strategies.

The external ear is composed of elastic cartilage. Microtia is a congenital malformation of the external ear that involves a small reduction in size or a complete absence. The aim of tissue engineering is to regenerate tissues and organs clinically implantable based on the utilization of cells and biomaterials. Remnants from microtia represent a source of cells for auricular reconstruction using tissue engineering. To examine the macromolecular architecture of microtia cartilage and behavior of chondrocytes, in order to enrich the knowledge of this type of cartilage as a cell reservoir. Auricular cartilage remnants were obtained from pediatric patients with microtia undergoing reconstructive procedures. Extracellular matrix composition was characterized using immunofluorescence and histological staining methods. Chondrocytes were isolated and expanded in vitro using a mechanical-enzymatic protocol. Chondrocyte phenotype was analyzed using qualitative PCR. Microtia cartilage preserves structural organization similar to healthy elastic cartilage. Extracellular matrix is composed of typical cartilage proteins such as type II collagen, elastin and proteoglycans. Chondrocytes displayed morphological features similar to chondrocytes derived from healthy cartilage, expressing SOX9, COL2 and ELN, thus preserving chondral phenotype. Cell viability was 94.6 % during in vitro expansion. Elastic cartilage from microtia has similar characteristics, both architectural and biochemical to healthy cartilage. We confirmed the suitability of microtia remnant as a reservoir of chondrocytes with potential to be expanded in vitro, maintaining phenotypical features and viability. Microtia remnants are an accessible source of autologous cells for auricular reconstruction using tissue engineering strategies.

Evaluación de zona dadora en reconstrucción auricular de microtia con técnica suprapericóndrica en la obtención de cartílago costal / Evaluation of donor site in auricular reconstruction of microtia with supraperichondrial costal cartilage harvest technique

Aim: To assess the presence of donor site sequel of patients undergoing ear reconstruction with costal cartilage harvest, using supraperichondrial technique. methods: Cross-sectional study; patients under 15 years. The cartilages were harvested with perichondrium. Three observers performed donor site assessment; they were independent to this study (validated Strasser score: deformity, asymmetry, contour and scar). Children and their mothers were applied satisfaction survey. Analysis of the association between variables: nonparametric tests. Results: 19 reconstructions, 18 patients, age 8 (6-15) years, follow-up 50 (14-96) months; number of rib cartilage harvested 3 (2-4) units. Expert assessment: excellent in 2 (10.5%) cases, good in 10 (52.6%), regular in 7 (36.8%). Most mothers and patients rated the result as good. There was no significant difference in the score, with respect to the number of harvested costal cartilages. To separate them by age, poorer results were obtained at surgery before 10 years of age than in older (p < 0.03). Conclusion: Ear reconstruction and supraperichondrial technique for costal cartilage allows obtain good results in donor site. There is high satisfaction when evaluated by the patient and his mother, as well as observers. The result is not dependent on the number of harvested cartilage, but is related to age at surgery, best results were obtained in patients operated over 10 years of age.

Objetivo: Evaluar presencia de secuela en zona dadora de pacientes sometidos a reconstrucción auricular con cartílago costal con técnica suprapericóndrica. material y método: Corte transversal; pacientes menores de 15 años. Cartílagos fueron levantados con pericondrio. Evaluación de zona dadora fue realizada por tres observadores independientes (escala validada de Strasser: deformidad, asimetría, contorno y cicatriz). A niños y madres se les aplicó encuesta de satisfacción. En el análisis de la asociación entre variables se utilizan pruebas no paramétricas. Resultados: 19 reconstrucciones, 18 pacientes, mediana edad 8 (6-15) años, seguimiento 50 (14-96) meses, número de cartílagos costales obtenidos 3 (2-4) unidades. Evaluación de expertos: excelente en 2 (10,5%) casos, bueno en 10 (52,6%) y regular en 7 (36,8%). La mayoría de las madres y pacientes calificó como bueno el resultado. No hubo diferencia significativa en el puntaje con respecto al número de cartílagos costales cosechados. Al separarlos por edad se obtuvo peores resultados en los intervenidos antes de los 10 años que en mayores (p < 0,03). Conclusión: La reconstrucción auricular con cartílago costal y técnica suprapericóndrica, permite obtener buenos resultados en zona dadora. Existe alta satisfacción al ser evaluada por el paciente y su madre, así como por los observadores. El resultado no es dependiente del número de cartílagos; sí en relación a la edad de la cirugía: mejores resultados en pacientes operados sobre los 10 años de edad, lo que concuerda con otros estudios.

Microtia: definición, clasificación y tratamiento: revisión de la literatura / Microtia: definition, classification and treatment: Literature review

El pabellón auricular es una importante unidad estética en el ser humano. Existe un grado variable de malformaciones, en Chile tiene una incidencia de 1 por cada 5600 nacidos vivos. Anatómicamente el pabellón auricular está compuesto por tres estructuras principales: complejo hélix antihélix, concha y lóbulo. Es según la anomalía que se presente en la anatomía externa la forma en que se clasificará, existiendo diversos sistemas para esto, algunos de ellos con utilidad anátomo quirúrgica.El eje principal del tratamiento de estas anomalías es la reconstrucción quirúrgica, teniendo disponible en la literatura variadas técnicas, como son el uso de implantes, reconstrucción protésica y la reconstrucción con injerto autólogo de cartílago costal, entre otras. Reinisch ha sido pionero en el uso de implantes para la reconstrucción, mientras que diversos autores han mostrado resultados satisfactorios con el uso de prótesis osteointegradas. Sin embargo, la técnica más aceptada y utilizada es la reconstrucción con injerto autólogo de cartílago costal, la cual fue descrita en sus inicios por Tanzer, Walton y Beahm, siendo perfeccionada posteriormente por Brent, quien propuso las bases para su desarrollo moderno. En la actualidad los métodos quirúrgicos más aceptados y utilizados son los descritos por Nagata y Firmin, ambos con excelentes resultados.

The ear is an important aesthetic unity in humans. There is a varying degree of malformations, Chile has an incidence of 1 per 5600 live births. Anatomically the pinna is composed of three main structures: helix antihelix complex, shell and lobe. It is according to the anomaly present in the external anatomy how it is classified, various systems exist for this, some of them with anatomic surgical utility. The main focus of treatment of these anomalies is the surgical reconstruction, taking various techniques available in the literature, such as the use of implants, prosthetic reconstruction and reconstruction with autologous rib cartilage graft, among others. Reinisch has pioneered the use of implants for reconstruction, while several authors have shown satisfactory results with the use of bone anchored prosthesis. However, the most accepted and used technique is the reconstruction with autologous rib cartilage graft, which was described at the beginning by Tanzer, Walton and Beahm and was later perfected by Brent, who proposed the foundation for modern development. Currently the most accepted and used surgical methods are described by Nagata and Firmin, both with excellent results.

Microtia-atresia: aspectos clínicos, genéticos y genómicos / Microtia-atresia: clinical, genetic and genomic aspects

En México, la microtia presenta una prevalencia de 7.37/10,000 recién nacidos, la cual es más alta que la reportada en otras poblaciones; por ejemplo, en Estados Unidos es de 2-3/10,000 recién nacidos. Se define como la malformación congénita del oído externo caracterizada por un pabellón auricular pequeño y con alteración en su forma. Se observa más frecuentemente de manera unilateral de lado derecho y en varones, y puede presentarse como defecto aislado o asociada con otras alteraciones como atresia y estenosis del conducto auditivo. Representa una de las principales causas de atención en la consulta externa del departamento de genética de instituciones de tercer nivel. Se considera como una malformación mayor con profundas repercusiones en la función auditiva, y que requiere de una atención multidisciplinaria. En una minoría de casos ha sido posible identificar una causa puramente genética o puramente ambiental, ya que en la mayoría la presentación es multifactorial. Debido a la importancia que representa esta alteración para los diferentes servicios de salud en México, es importante que se conozcan sus bases clínicas, moleculares y hereditarias.

Mexico has a prevalence of microtia of 7.37/10,000 (newborns), 3 times higher than the prevalence reported in other populations (USA 2-3/10,000). Microtia is defined as a congenital malformation of the external ear characterized by a small auricular lobe with an abnormal shape. It is more often unilateral and on the right side. Males are more frequently affected than females. It can occur as an isolated defect or can be associated with other abnormalities such as stenosis of the external auditory canal. In three of the main pediatric hospitals in Mexico, microtia is among the most important causes of attendance in the Genetics Department. Microtia-atresia must be considered as a major malformation with important repercussions in hearing function requiring multidisciplinary medical care in order to limit the disability associated and to provide genetic counseling. Its etiology is complex. Only in a minor number of cases it has been possible to identify a main genetic component (as in monogenic presentations) or a main environmental cause (as in fetal alcohol syndrome or pregestational diabetes). In most cases this malformation is multifactorial. Due to the relevance that the frequency of microtia atresia has in different health services in Mexico, it is important that all medical professionals are aware of its clinical, molecular and inherited characteristics.

[Microtia-atresia: clinical, genetic and genomic aspects]. / Microtia-atresia: aspectos clínicos, genéticos y genómicos.

Mexico has a prevalence of microtia of 7.37/10,000 (newborns), 3 times higher than the prevalence reported in other populations (USA 2-3/10,000). Microtia is defined as a congenital malformation of the external ear characterized by a small auricular lobe with an abnormal shape. It is more often unilateral and on the right side. Males are more frequently affected than females. It can occur as an isolated defect or can be associated with other abnormalities such as stenosis of the external auditory canal. In three of the main pediatric hospitals in Mexico, microtia is among the most important causes of attendance in the Genetics Department. Microtia-atresia must be considered as a major malformation with important repercussions in hearing function requiring multidisciplinary medical care in order to limit the disability associated and to provide genetic counseling. Its etiology is complex. Only in a minor number of cases it has been possible to identify a main genetic component (as in monogenic presentations) or a main environmental cause (as in fetal alcohol syndrome or pregestational diabetes). In most cases this malformation is multifactorial. Due to the relevance that the frequency of microtia atresia has in different health services in Mexico, it is important that all medical professionals are aware of its clinical, molecular and inherited characteristics.