Abstract
PurposeTo propose a new objective, video recording method for the classification of unilateral peripheral facial palsy (UPFP) that relies on mathematical algorithms allowing the software to recognize numerical points on the two sides of the face surface that would be indicative of facial nerve impairment without positioning of markers on the face.MethodsPatients with UPFP of different House–Brackmann (HB) degrees ranging from II to V were evaluated after video recording during two selected facial movements (forehead frowning and smiling) using a software trained to recognize the face points as numbers. Numerical parameters in millimeters were obtained as indicative values of the shifting of the face points, of the shift differences of the two face sides and the shifting ratio between the healthy (denominator) and the affected side (numerator), i.e., the asymmetry index for the two movements.ResultsFor each HB grade, specific asymmetry index ranges were identified with a positive correlation for shift differences and negative correlation for asymmetry indexes.ConclusionsThe use of the present objective system enabled the identification of numerical ranges of asymmetry between the healthy and the affected side that were consistent with the outcome from the subjective methods currently in use.
Highlights
Objective systems for grading unilateral peripheral facial palsy (UPFP) started to be proposed with the aim to overcome the several flaws revealed by the traditional, subjective methods
In an attempt to elaborate an objective method for this purpose, an automatic software-based system has previously been reported and validated for the evaluation of UPFP via the analysis of shifting of markers preliminarily placed on specific face regions [15, 16]
The system was appropriate for most UPFP cases and consistent with the outcome from the subjective HB grading system, it is likely that marker placement may represent a biasing variable that is conditioned by the examiner’s experience and by the different physiognomic characteristics of some affected individuals presenting with a poorly defined eyelid region, especially during closure and opening of the eyes
Summary
Objective systems for grading unilateral peripheral facial palsy (UPFP) started to be proposed with the aim to overcome the several flaws revealed by the traditional, subjective methods. In an attempt to elaborate an objective method for this purpose, an automatic software-based system has previously been reported and validated for the evaluation of UPFP via the analysis of shifting of markers preliminarily placed on specific face regions [15, 16]. The purpose of the present study was to elaborate a video recording automatic system for grading patients with UPFP without using facial markers. In this regard, the study group was composed of subjects who were previously classified. European Archives of Oto-Rhino-Laryngology (2021) 278:3541–3550 and validated with another objective video recording system [15, 16]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
