Optimization of 3D autologous chondrocyte-seeded polyglycolic acid scaffolds to mimic human ear cartilage.

Auricular reconstruction in children with microtia is one of the more complex procedures in plastic surgery. Obtaining sufficient native material to build an ear requires harvesting large fragments of rib cartilage in children. Herein, we investigated how to optimize autologous chondrocyte isolation, expansion and re-implantation using polyglycolic acid (PGA) scaffolds for generating enough cartilage to recapitulate a whole ear starting from a small ear biopsy. Ear chondrocytes isolated from human microtia subjects grew slower than microtia rib or healthy ear chondrocytes and displayed a phenotypic shift due to the passage number. Rabbit ear chondrocytes co-cultured with mesenchymal stem cells (MSC) at a 50 : 50 ratio recapitulated the cartilage biological properties in vitro. However, PGA scaffolds with different proportions of rabbit chondrocytes and MSC did not grow substantially in two months when subcutaneously implanted in immunosuppressed mice. In contrast, rabbit chondrocyte-seeded PGA scaffolds implanted in immunocompetent rabbits formed a cartilage 10 times larger than the original PGA scaffold. This cartilage mimicked the biofunctional and mechanical properties of an ear cartilage. These results indicate that autologous chondrocyte-seeded PGA scaffolds fabricated following our optimized procedure have immense potential as a solution for obtaining enough cartilage for auricular reconstruction and opens new avenues to redefine autologous cartilage replacement.

Comparison of First-Pass Effect in Aspiration vs. Stent-Retriever for Acute Intracranial ICA Occlusion.

The purpose of this study is to evaluate the best endovascular approach (aspiration or stent-retriever) and the impact of stent retriever size and length on clinical and angiographic outcomes in patients with acute intracranial ICA occlusion. We conducted a retrospective analysis of a prospective database of consecutive patients with acute intracranial ICA occlusion undergoing endovascular treatment in four Comprehensive Stroke Center between June-2019 and December-2020. We include 121 patients; Stent-retriever (SR) was used as first technical approach in 107 patients (88.4%) and aspiration was used in 14 patients (11.6%). SR group had higher rate of FPE compared to aspiration group (29 vs. 0%, p = 0.02). In SR subgroup, treatment highlighted higher FPE in the 6 × 50 SR (37.7%), than in the rest of the SR which are 21.2% (4-5 mm size and 20-50 mm length SR) and 19% (6 mm size and 25-40 mm length SR), but it was not found to be statistically significant. There were no other significant differences across the groups regarding primary angiographic or clinical outcomes. In our intracranial ICA occlusion series, stent retrievers were superior to direct aspiration in obtaining FPEs and mFPEs, and longer devices achieved better results with no statistically significant difference. Further studies evaluating the effects of different ICA clot removal approaches are warranted to confirm these results.