Background/Objectives: This study aimed to describe and quantify facial soft tissue changes in two patients who underwent radiotherapy (RT) for head and neck cancers, using three-dimensional (3D) stereophotogrammetry and surface deviation analysis. The aims were (i) to assess the progression of morphological alterations over time (ii) and to evaluate the clinical potential of 3D surface mapping in documenting RT-related aesthetic changes. Methods: Two patients with head and neck cancer undergoing RT were analyzed using three-dimensional stereophotogrammetry (3dMD Trio-system, Atlanta, GA, USA) at three timepoints: before RT (T0), 45 days after the start of RT (T1), and 6 months after the start of RT (T2). Facial 3D scans were processed using Geomagic Control 2014 software (v.3D Systems, Morrisville, NC, USA) to perform standardized alignments and calculate volumetric deviations, create colorimetric deviation maps, and conduct Root Mean Square (RMS) analysis. Results: Between T0 and T1, both patients showed soft tissue volume reduction, primarily in the mandibular and submental regions, likely reflecting acute treatment effects and weight loss. Between T0 and T2, an increase in soft tissue volume was observed, especially in the lower face and neck, consistent with late radiation effects such as lymphedema and post-treatment weight gain. RMS values ranged from 5.53 mm to 6.87 mm across patients and time points, indicating measurable morphological changes. The upper third of the face remained stable and served as a reliable reference region for alignment. Conclusions: RT may be associated with significant, region-specific changes in facial and cervical soft tissues in HNC patients, but these preliminary observations must always be correlated with weight loss and confirmed by further studies. 3D stereophotogrammetry is a reliable, non-invasive method for detecting and quantifying these alterations over time. This technique can offer valuable insights for clinical monitoring and could promote better patient counseling and potentially mitigate the psychological burden associated with facial changes.
Schiavelli et al. (Fri,) studied this question.