Tridimensional-volumetric analysis of free flaps in head and neck surgery and functional assessment: towards a quantitative planning of reconstruction in the oral cavity.

Reconstruction with free flaps represents the cornerstone of head and neck surgery following extensive resections. Despite advances in flap harvesting and microvascular techniques, challenges remain due to the anatomical and functional complexity of this region. Flap’s remodeling over time poses a significant challenge in the pre-operative planning, being a key element related to functionality and thus patient’s quality of life. Although studies addressing the problem are available in literature, none has provided a combined analysis of flap tridimensional changes and functional assessment over time. This study aims to (1) quantitatively analyze the volumetric and morphological evolution of free flaps used in oral cavity reconstruction, and (2) correlate these changes with functional outcomes (i.e. swallowing, speech, and chewing) , likewise considering relevant patient’s clinical variables (e.g. BMI, diabetes). This is a retrospective and prospective study including 22 patients who underwent total, subtotal, or hemi-glossectomy with free flap reconstruction at the University of Padua from 2020 to 2024. Inclusion criteria comprise availability of high-quality postoperative imaging (CT, MRI, or PET-CT/PET-MRI), surgical report, and at least 6 months follow-up with no evidence of local recurrence. Flap’s dimensional parameters (volume, thickness, and surface area) will be analyzed using 3D reconstruction software (Mimics and 3-Matic, Materialise, Leuven, Belgium). Functional outcomes will be assessed via objective tests (videofluoroscopy and fiberoptic endoscopic evaluation of swallowing reported with standardized scale [Donzelli]), and patient-reported outcome measures (MDADI, SHI, EORTC H&N35, PSS-HN). This study aims to identify patterns of flap remodeling over time and determine morpho-functional predictors to consider during pre-surgical planning. By combining volumetric 3D analysis with functional evaluation, the results may offer new insights for planning and optimization of free flap reconstruction in head and neck surgery, ultimately contributing to an improved quality of life. In conclusion, the integration of quantitative imaging and functional assessment could lead to a more precise and tailored approach to oral cavity reconstruction.