Validation of a New Graphic Facial Nerve Grading System: FAME Scale.

BACKGROUND AND OBJECTIVE

Most of the existing qualitative facial nerve grading systems are very subjective while the quantitative grading systems are more complex, require longer data input time and specific software. There is a need for having a scoring system with graphic criteria to improve the subjectivity, reliability and convenience. We aimed to develop and validate such a reliable graphic scale for use in Bell's palsy.

METHODS

Face videos of patients with unilateral facial paralysis were recorded using smartphones and analyzed for six items including five voluntary facial movements apart from complications of facial palsy (synkinesis, hyperkinesis, and contracture). 15 videos were used for pilot study, 75 for the development of scale and 110 for its validation. Each video was rated on two separate occasions by 3 independent raters, a score of 0-4 was assigned to each item using the graphic scoring criteria, and a composite score was obtained (range 0-24). Five disease severity categories: normal (score 0), mild (score 1-6), moderate (score 7-12), severe (score: 13-18) and profound facial weakness (score: 19-24).

RESULTS

The proposed scale and its component items had high inter-rater and intra-rater reliability (Kappa >0.7). Good correlation (Pearson co-efficient >0.7) was seen among the voluntary movements. The proposed scale is a valid tool to score motor deficits and complications of facial palsy.

CONCLUSIONS

The proposed scale is a valid and reliable graphic scale to describe facial motor dysfunction and its secondary defects.