An objective, markerless videosystem for staging facial palsy

Abstract

Purpose To 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. Methods Patients 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. Results For each HB grade, specific asymmetry index ranges were identified with a positive correlation for shift differences and negative correlation for asymmetry indexes. Conclusions The 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.

Toward an application of automatic evaluation system for central facial palsy using two simple evaluation indices in emergency medicine

“…Previous studies on the automatic evaluation of facial palsy using video or image analysis can be divided into those that focus on central facial palsy (CFP) 9 , 10 and those that do not distinguish between CFP and peripheral facial palsy (PFP) 11 – 25 . For CFP, palsy presents on the lower face, whereas for PFP, palsy presents on the entire face.…”

“…Various methods for automatically evaluating peripheral or overall facial palsy have been proposed 11 – 25 . These methods can be divided into those that use facial landmarks and those that do not.…”

“…Moreover, methods that use static images, not videos, may fail to identify mild palsy. Monini et al 25 performed a video analysis to classify unilateral PFP, focusing on two facial movements (forehead frowning and smiling). They suggested that the landmark-based method (markerless objective method) may be useful for implementing conventional clinical classifications.…”

Facial nerve palsy: Narrative review on the importance of the eye and its assessment

“…Grading systems for evaluating FNP FDI 20 FaCE 21 Psychosocial scale of facial appearance 22 FACE-Q 23 House-Brackmann 3 Sunnybrook 4 Yanagihara facial nerve grading system 24 FNGS 2.0 25 eFACE 26 Glasgow facial palsy scale 27 Facogram 28 The Nottingham system 29 Moiré topography index 30 Computerized facial analyses 7,[31][32][33][34][35][36][37][38][39] Manual measurement of facial points [40][41][42] Abbreviations: FaCE, facial clinimetric evaluation scale; FDI, facial disability index; FNGS, facial nerve grading system; FNP, facial nerve palsy.…”