Combining Virtual Surgical Planning, Intraoperative Navigation, and 3-Dimensional Printing in Prosthetic-Based Bilateral Microtia Reconstruction.

Reconstructing auricular deformities for bilateral microtia is a demanding challenge especially after failed autologous reconstruction. This case report presents a novel application of virtual surgical planning, computer-assisted design, and intraoperative surgical navigation to preplan and execute placement of custom-tailored silicone auricular prostheses and titanium osseointegrated implants for a bone-anchored hearing aid system in a patient with Treacher Collins syndrome in whom autologous reconstruction had previously failed. Through a collaborative approach between the reconstructive surgeon and anaplastologist, the implementation of advanced digital technologies may offer a superior esthetic and functional outcome to patients with previously failed reconstruction.

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.

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.