Software-based video analysis of functional outcomes of face transplantation

Quantification of Facial Allograft Edema During Acute Rejection: A Software-Based 3-Dimensional Analysis

BACKGROUND

Acute rejection (AR) is a common complication in facial transplant (FT) patients associated with allograft edema and erythema. Our study aims to demonstrate the feasibility of using software-based 3-dimensional (3D) facial analysis to quantify edema as it resolves during/after AR treatment in an FT patient.

METHODS

Our patient is a 23-year-old man who underwent a face and bilateral hand allotransplant in August 2020. The Vectra H1 (Canfield, Fairfield, NJ) portable scanner was used to capture 3D facial images at 8 time points between postoperative day (POD) 392 and 539. The images were analyzed with the Vectra Software using a rejection-free image (POD 539) as a control.

RESULTS

Edema increased in the periorbital, lower third, and submandibular regions before AR treatment (POD 392-415). At POD 448, total facial edema was reduced to near baseline values in response to plasmapheresis and thymoglobulin (+156.94 to +28.2 mL). The fastest and most notable response to treatment was seen in the periorbital region, while some edema remained in the submandibular (+19.79 mL) and right lower third (+8.65 mL) regions. On POD 465, after the initial improvement, the edema increased but was resolved with steroid use. Facial edema did not correlate with the histopathological evaluation in our patient.

CONCLUSIONS

We demonstrated the feasibility of analyzing 3D facial images to quantify edema during/after AR treatment in an FT patient. Our analysis detected edema changes consistent with AR followed by an improvement after treatment. This technology shows promise for noninvasive monitoring of FT patients.

Software-based Detection of Acute Rejection Changes in Face Transplant

BACKGROUND

 An objective, non-invasive method for redness detection during acute allograft rejection in face transplantation (FT) is lacking.

METHODS

 A retrospective cohort study was performed with 688 images of 7 patients with face transplant (range, 1 to 108 months post-transplant). Healthy controls were matched to donor age, sex, and had no prior facial procedures. Rejection state was confirmed via tissue biopsy. An image-analysis software developed alongside VicarVision (Amsterdam, Netherlands) was used to produce R, a measure of differences between detectable color and absolute red. R is inversely proportional to redness, where lower R values correspond to increased redness. Linear mixed models were used to study fixed effect of rejection state on R values. Estimated marginal means of fitted models were calculated for pairwise comparisons.

RESULTS

 Of 688 images, 175, 170, 202, and 141 images were attributable to Banff Grade 0,1,2, and 3, respectively. Estimated change in R value of facial allografts decreased with increasing Banff Grade (p = 0.0001). The mean R value of clinical rejection (Banff Grade ⅔) (16.67, 95% Confidence Interval [CI] 14.79-18.58) was lower (p = 0.005) than non-rejection (Banff Grade 0/1) (19.38, 95%CI 17.43-21.33). Both clinical and non-rejection mean R values were lower (p = 0.0001) than healthy controls (24.12, 95%CI 20.96-27.28).

CONCLUSION

 This proof-of-concept study demonstrates that software-based analysis can detect and monitor acute rejection changes in FT. Future studies should expand on this tool's potential application in telehealth and as a screening tool for allograft rejection.

Vascularized Composite Allotransplantation in Burn Reconstruction: Systematic Review and Meta-analysis

Vascularized composite allotransplantation has been successfully employed for burn reconstruction since 2003. However, its safety in this population has been questioned due to high levels of alloimmunization from burn care-related tissue exposures. To investigate this, a systematic review of vascularized composite allotransplantation employed for burn reconstruction was conducted, evaluating literature from January 2000 to September 2019. Articles containing vascularized composite allotransplantation, composite tissue allotransplantation, and burn reconstructive surgery were included; articles without published outcomes were excluded. Observational meta-analysis of pooled mortality and acute rejection episodes relative to allograft type (face vs extremity) and reconstruction type (burn vs non-burn) was performed. Twenty-four of the 63 identified articles met the criteria for inclusion, with 5 more articles added after secondary review. To date, 152 allotransplantations have been performed in 117 patients: 45 face transplants and 107 extremity transplants. Of these, 34 (22%) were performed for burn reconstruction in 25 patients (21%) with an overall higher 1-year mortality rate (12.0% vs 1.1%, P  = .030). Of these deaths, 75% received three or more simultaneous allografts. Additionally, more episodes of acute rejection occurred compared to non-burn patients (4.4 vs 2.4, P  = .035). Vascularized composite allotransplantation performed for burn reconstruction was found to be associated with a greater risk of 1-year mortality and nearly twice the number of episodes of acute rejection. Future studies should seek to identify unique risk factors of burn patients undergoing this operation and evaluate the relationship between antigenic burden and surgical outcomes.

Speech Characteristics and Oromyofunctional Outcomes in Two Bimaxillary Face Transplantation Patients in Helsinki

OBJECTIVES/HYPOTHESIS

Facial functional restoration is one of the main goals in face transplantation. We report the oromyofacial function outcomes of two bimaxillary face transplantation (FT) patients in Helsinki.

STUDY DESIGN

Outcome Study.

METHODS

Two male patients, aged 34 and 59, had severe functional facial disabilities following self-inflicted gunshot injuries sustained to their mid and lower faces several years earlier. Both underwent tooth-bearing maxillomandibular face transplantation in 2016 and 2018. We collected data regarding speech, swallowing, sensory recovery, motor recovery, and olfaction prior to transplantation. Patient charts were reviewed from the follow-up period of 4 and 2 years, respectively.

RESULTS

Speech intelligibility, acceptability, and articulation continued to improve during follow-up for both patients. Voice quality and resonance were mainly normal at last follow-up. Swallowing improved once lip occlusion was regained, with only minor aspiration evident on videofluorography. Both patients had significant improvement in facial mimic muscle function after FT. The first patient who only had buccal sensory nerves connected has only recovered protective facial sensation, whereas our second patient with buccal, infraorbital, and alveolar nerves connected has almost complete facial two-point discrimination.

CONCLUSION

Both patients have regained satisfactory facial sensory and motor function. Sensory recovery seems to be faster and more precise if multiple sensory nerve coaptations are performed. Swallowing and speech have continued to improve over time although not reaching the level of the normal population. We demonstrate how speech-corrective surgery can safely be performed in a FT patient and can improve speech recovery.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Enzymatic debridement for burn wound care: Interrater-reliability and impact of experience in post-intervention therapy decision

INTRODUCTION

Enzymatic debridement (ED) has become a reliable tool for eschar removal. Although ED application is simple, wound bed evaluation and therapy decision post-intervention are prone to subjectivity and failure. Experience in ED might be the key, but this has not been proven yet. Aim of this study was to assess interrater reliability (IR) in post-intervention wound bed evaluation and therapy decision as well as the impact of experience. In addition, the authors introduce video assessment as a valuable tool for post-ED decision making and education.

MATERIAL AND METHODS

A video-based survey was conducted among physicians with various experience in ED. The survey involved multiple choice and 5-point Likert scale questions about professional status, experience in ED, confidence in post-ED wound bed evaluation and therapy decision. Subsequently, videos of 15 mixed pattern to full thickness burns immediately after removal of the enzyme complex were demonstrated. Participants were asked for evaluation of each burn wound, including bleeding pattern and consequent therapy decision. IR ≥80% was considered as a consensus. Responses were stratified according to participants' experience in applying ED (<10; 10-19; 20-49; ≥50 applications). IR was assessed by Chi^2-test (raw agreement (RA); ≥80% was considered as a consensus) and by Krippendorff's Alpha-test. In addition, expert consensus for therapy decision was compared to the actual clinical course of each shown patient. Last, participants were asked for their opinion on video as an assessment tool for post-ED wound bed evaluation, decision making and training.

RESULTS

31 physicians from 11 burn centers participated in the survey. Overall consensus (RA≥80%) in post-ED wound bed evaluation and therapy decision was achieved in 20 and 40%, respectively. Krippendorff's Alpha are given by 0.32 (95% CI: 0.15,0.49) and 0.31 (95% CI: 0.16,0.47), respectively. Subgroup analysis revealed that physicians with high experience in ED achieved significantly more consensus in post-intervention wound bed evaluation and therapy decision compared to physicians with moderate experience (60% vs. 13.3%; p=0.02 and 86.7 vs. 33.3%; p=0.04, respectively). Video analysis was considered a feasible (90.3%) and beneficial (93.5%) tool for post-intervention wound bed evaluation and therapy decision as well as useful for training purposes (100%).

CONCLUSION

Reliability of wound bed evaluation and therapy decision after ED depends on the experience of the rating physician. Video analysis is deemed to be a valuable tool for ED evaluation, decision making and user training.

Recognizing Emotional Expression as an Outcome Measure After Face Transplant

IMPORTANCE

Limited quantitative data exist on the restoration of nonverbal communication via facial emotional expression after face transplant. Objective and noninvasive methods for measuring outcomes and tracking rehabilitation after face transplant are lacking.

OBJECTIVE

To measure emotional expression as an indicator of functional outcomes and rehabilitation after face transplant via objective, noninvasive, and nonobtrusive software-based video analysis.

DESIGN, SETTING, AND PARTICIPANTS

This single-center case-control study analyzed videos with commercially available video analysis software capable of detecting emotional expression. The study participants were 6 patients who underwent face transplant at Brigham and Women's Hospital between April 2009 and March 2014. They were matched by age, race/ethnicity, culture, and sex to 6 healthy controls with no prior facial surgical procedures. Participants were asked to perform either emotional expressions (direct evaluation) or standardized facial movements (indirect evaluation). Videos were obtained in a clinical setting, except for direct evaluation videos of 3 patients that were recorded at the patients' residences. Data analysis was performed from June 2018 to November 2018.

MAIN OUTCOMES AND MEASURES

The possibility of detecting the emotional expressions of happiness, sadness, anger, fear, surprise, and disgust was evaluated using intensity score values between 0 and 1, representing expressions that are absent or fully present, respectively.

RESULTS

Six patients underwent face transplant (4 men; mean [SD] age, 42 [14] years). Four underwent full face transplants, and 2 underwent partial face transplants of the middle and lower two-thirds of the face. In healthy controls, happiness was the only emotion reliably recognized in both indirect (mean [SD] intensity score, 0.92 [0.05]) and direct (mean [SD] intensity score, 0.91 [0.04]) evaluation. Indirect evaluation showed that expression of happiness significantly improved 1 year after transplant (0.04 point per year; 95% CI, 0.02 to 0.06 point per year; P = .002). Expression of happiness was restored to a mean of 43% (range, 14% to 75%) of that of healthy controls after face transplant. The expression of sadness showed a significant change only during the first year after transplant (-0.53 point per year; 95% CI, -0.82 to -0.24 point per year; P = .005). All other emotions were detectable with no significant change after transplant. Nearly all emotions were detectable in long-term direct evaluation of 3 patients, with expression of happiness restored to a mean of 26% (range, 5% to 59%) of that of healthy controls.

CONCLUSIONS AND RELEVANCE

Partial restoration of facial emotional expression is possible after face transplant. Video analysis software may provide useful clinical information and aid rehabilitation after face transplant.