[Category of facial symmetry perception after maxillary reconstruction using anterolateral thigh flap].

ABSTRACT

OBJECTIVE: To preliminarily establish a category of facial symmetry perception after maxillary reconstruction using anterolateral thigh flap (ALTF) by the methods of stereophotogrammetry and subjective assessment. METHODS: The patients underwent maxillectomy due to neoplasms invasion, and all the maxillary defects were reconstructed using ALTF.Three-dimensional (3D) photographs were captured from the patients with a stereophotogrammatrical camera set-up.In the Geomagic software, the mirror image was created by reflecting along an arbitrary plane outside of the face.After the registration, the postoperative side on the original 3D photograph was segmented into 6 areas.The 3D change of the facial soft-tissue was measured using surface-based color map.Twenty laypeople took part in the study as observers, and they were asked to rate the 3D photographs using 5 point Likert-type scale according to their own aesthetic standard.The soft tissue asymmetry was graded according to the score.The collected data were subjected to statistical analysis using the SPSS 24.0 software. RESULTS: In the study, 44 subjects were recruited (21 males and 23 females, age range from 19 to 79 years).The soft-tissue symmetry was graded into three levels according to the subjective scores.The grade Ⅰ was basically symmetrical.The grade Ⅱ was slightly asymmetrical.The grade Ⅲ was obviously asymmetrical.Statistically significant differences were found in the suborbital (P < 0.05) and zygomatic (P < 0.05) areas when comparing all grades of soft-tissue asymmetry, and in the buccal (P < 0.05) and superiolabial (P < 0.05) areas when comparing grades Ⅰ and Ⅲ.The extent of maxillary defect had significant impact on the symmetry of the midface soft-tissue after maxillary reconstruction. CONCLUSION: Varying extent maxillectomy would result in varying degrees of asymmetry, and cause different grades of symmetry perception even if they had been reconstructed using ALTF.The higher the grade, the worse the symmetry of facial soft-tissue.Suborbital and zygomatic areas were important aesthetic units that affected the facial symmetry perception, followed by buccal and superiolabial areas.The clinicians should pay attention to the soft-tissue support in these areas when reconstructing the maxillary defect, especially large defect with orbital floor involved.