Modular Component Assembly Approach to Microtia Reconstruction.

Background Current methods of microtia reconstruction include carving an auricular framework from the costal synchondrosis. This requires considerable skill and may create a substantial defect at the donor site. Objective To present a modular component assembly (MCA) approach that minimizes the procedural difficulty with microtia repair and reduces the amount of cartilage to a single rib. Design, Setting, and Participants Ex vivo study and survey. A single porcine rib was sectioned into multiple slices using a cartilage guillotine, cut into components outlined by 3-dimensional printed templates, and assembled into an auricular scaffold. Electromechanical reshaping was used to bend cartilage slices for creation of the helical rim. Chondrocyte viability was confirmed using confocal imaging. Ten surgeons reviewed the scaffold constructed with the MCA approach to evaluate aesthetics, stability, and clinical feasibility. The study was conducted from June 5 to December 18, 2014. Main Outcomes and Measures The primary outcome was creation of a modular component assembly method that decreases the total amount of rib needed for scaffold construction, as well as overall scaffold acceptability. The surgeons provided their assessments through a Likert-scale survey, with responses ranging from 1 (disagree with the statement) to 5 (agree with the statement). Thus, a higher score represents that the surgeon agrees that the scaffold is structurally and aesthetically acceptable and feasible. Results An auricular framework with projection and curvature was fashioned from 1 rib. The 10 surgeons who participated in the survey indicated that the MCA scaffold would meet minimal aesthetic and anatomic acceptability. When embedded under a covering, the region of the helix and antihelix of the scaffold scored significantly higher on the assessment survey than that of an embedded alloplast implant (mean [SD], 4.6 [0.97] vs 3.5 [1.27]; P  = .007). Otherwise, no significant difference was found between the embedded MCA and alloplast implants (4.42 [0.48] vs 3.87 [0.41]; P  = .13). Cartilage prepared with electromechanical reshaping was viable. Conclusions and Relevance This study demonstrates that 1 rib can be used to create an aesthetic and durable framework for microtia repair. Precise assembly and the ability to obtain thin, uniform slices of cartilage were essential. This cartilage-sparing MCA approach may be an alternative to classic techniques. Level of Evidence NA.