Validation of the objective assessment of facial movement with a new software-based system

Abstract

Background: Most used subjective Unilateral Peripheral Facial Palsy (UPFP) grading systems are characterized by high variability and low reproducibility and doesn’t allow a separate evaluation of single facial regions.

Objective: To assess the reliability of a new objective method for classification of UPFP, comparing it with House-Brackmann (HB) and Sunnybrook facial grading (SFGS) systems.

Method: Forty-seven patients affected by UPFP of different HB grade were included. Each patient underwent a blinded examination by three different operators, via the two subjective methods (HBGS and SFGS) and a newly proposed objective one, that was obtained from a digital video-analysis, named SMART FACIAL system. Results were converted by validated conversion scales into HBGS grades and statistically compared.

Results: In 87,23% (n° 41 pts) consistency was found between the grades obtained with all the three evaluation methods; in 10,41% (n°5 pts), between HBGS and SFGS grade and in 2,08% (n°1 pt) between HBGS grades and SMART-FACIAL system. Statistical analysis showed significant correlation among the three systems (p < .000).

Conclusions: The SMART FACIAL system presents high reliability also in comparison with the most frequently used subjective methods.

Significance: This method represents a fast, simple and thorough way to analyze UPFP, especially during physical rehabilitation.

Chinese abstract

背景：最常用的主观单侧周围性面神经麻痹（UPFP）分级系统的特点是高度可变性和低度重现性, 并且不能对单个面部区域分别进行评估。

目的：评估一种新的UPFP分类的客观方法的可靠性, 并与House-Brackmann（HB）和Sunnybrook面部分级（SFGS）系统进行比较。

方法：纳入47例不同HB级的UPFP患者。每位患者由三位操作者用两种主观方法（HBGS和SFGS）和一种新提出的客观方法进行盲法检查。新方法是通过数字视频分析（名为SMART FACIAL系统）而获得的。用认可的转换量表将检查结果转换为HBGS等级, 并对其进行统计学比较。

结果：在所有三种评估方法获得的等级之间发现87,23％（n°41 pts）的一致性；在HBGS和SFGS等级之间, 一致性为10,41％（n°5pts）；在HBGS等级和SMART-FACIAL系统之间, 一致性为2,08％（n°1pt）。统计分析显示, 三个系统之间存在显著相关性（p <.000）。

结论：与最常用的主观方法相比, SMART FACIAL系统同样具有高度可靠性。

意义：这种方法是一种快速、简单、全面的分析UPFP的方法, 用于身体康复期间, 尤其如此。

Keywords:

• Facial palsy
• grading system
• House–Brackmann grading system
• Sunnybrook grading system
• objective grading
• videotaping

Disclosure statement

No potential conlict of interest was reported by the authors.