Three-Dimensional Facial Imaging: A Comparative Assessment of the Clinical Applicability of State-of-the-Art...

Objective: To compare the clinical applicability in terms of observer perception, patient perception, and clinical usability of stereophotogrammetry (SPG) and both static and portable structured light (SL) three-dimensional (3D) face scanners. This comparison was based on the perception of medical observers, nonmedical observers, and patients themselves, using two-dimensional (2D) photographs as clinical reference. Material and Methods: Facial images of 20 patients (12 females and eight males) were obtained using a professional camera (clinical reference) and three facial scanners: Vectra H1 (SPG), RAYFace RFS200 (static SL), and iReal 2E (portable SL). Instant similarity rank (ISR) and similarity score (SS) were evaluated by seven medical and six nonmedical observers, and intra- and interobserver reliability were calculated. Patients rated the overall SS (OSS) and comfort. Scanning time, processing time, need for image retake, and user-friendliness were rated by two operators who captured the images. Results: SPG obtained the best ISR, followed by static and portable SL. All scanners showed overall good SS and OSS. Static SL was the fastest, whereas SPG and portable SL recorded same total time. Retake rates for SPG, static SL, and portable SL were 10%, 15%, and 35%, respectively. User-friendliness and comfort ranged from moderate to good for all scanners. Conclusion: All tested scanners show a good clinical applicability, even though each scanner came with specific advantages and drawbacks for clinical use. SPG excelled in instant similarity, but had slower processing times. Static SL offered a balance of speed, comfort, and user-friendliness, though not always the best in similarity. Portable SL had higher retake rates and moderate comfort and user-friendliness. Similarity perception across scanners was comparable for both medical and non-medical observers, highlighting the need for clinicians to consider all scanner features to best meet clinical requirements.