Application of chimeric flaps for complex orbitomaxillary reconstruction in sinonasal malignancy

Sinonasal malignancies are rare tumors, and a subset of these patients presents with involvement of the orbitomaxillary area, resulting in a complex maxillectomy defect, which warrants primary reconstruction. Complexity increases with globe preservation, which mandates structural support to the globe, ideally reconstructed using a vascularized osseous flap. Such complex defect reconstruction requires multiple components, which are titrated according to the complex three-dimensional defects.

This study aims to evaluate the outcomes of primary orbitomaxillary reconstruction in sinonasal malignancy using multicomponent chimeric flaps, which included osseous chimeric flaps for globe-preserving total maxillectomy and soft tissue chimeric flaps for the remaining orbitomaxillary defects.

A retrospective observational study was conducted between June 2024 and April 2026 at a tertiary referral center. The cohort included consecutive patients with modified Brown type 3 to 6 maxillectomy defects having sinonasal malignancy, which were primarily reconstructed with chimeric flaps. Data on the pathology, type of orbito maxillectomy defects, and types and components of chimeric flaps were collected. Outcomes were measured by flap survival, re-explorations, wound healing compromise, and delays in the start of adjuvant therapy. Specifically for orbital preservation patients, further assessment was made on the presence of diplopia or enophthalmos.

All 11 patients included in the study underwent a chimeric flap for orbitomaxillary defects. The most common pathology was squamous cell carcinoma. Seven (64%) were soft tissue chimeric flaps, and four (36%) were osseous chimeric flaps. All flaps survived completely. Satisfactory wound healing and contour restoration were achieved in all patients.

Chimeric flaps with their multiple components, which can be contoured according to the complex three-dimensional orbitomaxillary defects, achieves primary healing. For total maxillectomy with globe preservation, bone reconstruction is warranted. Orbital bone reconstruction use of 3D model for contouring the bone strut and the orbital floor mesh can achieve accurate reconstruction for such complex defects.