Standardization of flap design for oropharyngeal reconstruction after cancer ablation surgery

A variety of residual defects containing many sulci and fossae in the oropharyngeal cavity make it extremely difficult to achieve an adequate flap design as well as the functional reconstruction of the complex defects after ablation surgery for oropharyngeal tumors. This study attempted to standardize flap design for the different types of defects in order to produce a better functional reconstruction of intra-oral defects. The oropharyngeal defects were classified into 6 Zones. When the defect involves only the mouth floor, it was classified as Zone 1. A hemi tongue was classified as Zone 2. A defect involving the mouth floor and a part of the tongue was classified as Zone 3. A defect involving the mouth floor, a part of the tongue and the tonsil was classified as Zone 4. A defect involving the mouth floor, a part of the tongue, tonsil and soft palate was classified as Zone 5. A defect involving the pharyngeal wall was classified as Zone 6. The following four types of forearm free flap designs were applied to each defective Zone accordingly: Type I flap design - an unilobed design for reconstructing Zone 1, 2 and 6 defects, Type II design - bilobed design for reconstructing Zone 3 defects, Type III design - trilobed design for reconstructing Zone 4 defects and Type IV design for reconstructing Zone 5 defects. During 1999 to 2002, 91 patients with oropharyngeal defects underwent a reconstruction using these standardized forearm free flap designs. The Type I design was used in 41 cases, the Type II design in 18 cases, the Type III design in 10 cases and the Type IV design in 22 cases. In all patients, the decannulation was successful, and the swallowing and deglutination functions were within the normal parameters. There was less nasal escape of the voice and the regurgitation of food than that observed using the conventional flap design method. Effective and functional reconstructions with minimal morbidities are possible with the application of the standardized forearm free flap design in oropharyngeal defects.