Hebel, Nathan SD

Purpose: Examining the outcomes and progression of face transplants has expanded to include the recent advancements in artificial intelligence. This novel methodology has allowed for the objective exploration of emotional expression. To our knowledge, this examined emotional expression has yet to be correlated to the hypothesized functioning of the allograft. We have combined the result of the AI software with a software analyzing smile excursion; demonstrating the progression of the allograft in our face transplant patient. This study helps illuminate the software possibilities for objective measures in transplant progression. Methods: Images were analyzed from our face transplant patient post-operatively at approximately 6-month intervals for four years. The still images for each time interval include both a neutral facial expression and a full-face smile with teeth. The images were taken from video clips of the patient and then analyzed using the FACEgram software (Hadlock & Urban, 2012). The measurements of the smile excursion were standardized based off of the pupil diameter and excursion was measured relative to the neutral expression of each time period. The emotional expression data was acquired using FaceReader AI software from Noldus Information Technology (Wageningen, The Netherlands). The emotional analysis was done on 2 second clips from clinical videos of the patient, the same videos used for the still images. This data was correlated with the smile excursion measurements. Results: The post-operative smile excursion analysis from 6 to 49 months demonstrated a near double in smile excursion from 3.58mm to 6.04mm. The smile excursion data has a squared correlation of 0.705; a strong upward linear trend of excursion. From 6 to 35 months, the happy emotion increased gradually from 0% to 15.8% (49-month data unavailable). Performed correlative analysis showed a positive correlation coefficient of 0.63. This moderate to strong correlation demonstrates the intuitive relationship of happy emotion and lip excursion during full face smiling. The findings also substantiate the AI software’s detection of increasing activity in the lip corner puller action unit from zero to 3/5 intensity over the same period. Conclusion: This study demonstrates the correlation of smile excursion to happy emotional expression in our face transplant patient. The correlation square of the lip excursion shows a trend of increased functioning of the allograft over time; substantiating the AI’s finding. This data provides evidence for the use of artificial intelligence as a measure of transplant strength progression. The conjoined analysis of patient images and videos has supported proof for the ability to analyze transplant healing progression and efficacy in an objective form. Hadlock, T. A., & Urban, L. S. (2012). Toward a Universal, Automated Facial Measurement Tool in Facial Reanimation. Archives of Facial Plastic Surgery,14(4). doi:10.1001/archfacial.2012.111

Purpose: Exceptional functional results can be obtained with toe to thumb transfers; however objective measures to evaluate the aesthetic outcome of a toe to thumb transfers remains elusive. Aesthetic evaluation of a reconstruction when performed by external raters or the patient, may be influenced by expert knowledge, emotional antecedent, or ethnic or regional bias. In this study, we were interested in determining the observers’ instantaneous, reflexive responses to the toe to thumb transfer as determined by eye-tracking analysis. Methods: 13 patients with unilateral great toe to thumb transfers were photographed using a standardized technique. None had undergone secondary procedures that changed the appearance of the transferred toe. Both hands were photographed side by side in each image. A dorsal and palmar image was taken, producing 26 photos in total. 40 observers (Average age 41.39, 14-65 yo, 18 males, 22 females), blinded to the procedure, were asked to evaluate each image for symmetry between the hands. An infrared eye-tracking camera continuously recorded their eye movements. Participants were allowed to evaluate each image for 6 seconds. Data was evaluated to determine the percent of time that was devoted to evaluating each portion of the photograph. The percent time spent in each of the lookzones was recorded. Results: i) Observers spent an average of 17.7% of their time evaluating the reconstructed thumb compared to the entire bilateral hand. This was on average 63% more time looking at the reconstructed thumb compared to the normal control thumb. (p value<0.01) ii) Observers spent 43.9% of the time looking at the reconstructed thumb compared to the entire hand of the same side. They spent 31.6% of the time looking at the normal control thumb compared to the entire hand of the same side (p value<0.01, mean 0.36 seconds on the abnormal thumb (SD 0.439)), vs. mean 0.22 seconds on normal control thumb (SD 0.305); mean 0.82 seconds on abnormal hand (SD 0.45), mean 0.69 seconds on normal contralateral hand (SD 0.423); mean 0.74 on entirely normal bilateral hand (SD 0.41)). iii) Areas of significant attention as visualized by heatmaps representing where observers focus their attention include abnormal nailbed and scar tissue at the junction between the toe and native hand skin. Conclusion: The technique described above may represent a novel and objective technique for quantifying observers’ gaze with respect to toe to thumb reconstructions and the un-altered contralateral thumb. It could be applied to other areas of hand reconstruction to help determine aesthetic outcomes. The present pilot suggests that symmetric nail size may be an area of importance for creating the sense of aesthetic success. Incorporation of this data into surgical counseling may assist the patient and medical team focus on surgical-decision making priorities.