House-Brackmann scale[17]House JW, Brackmann DE. Facial nerve grading system. Otolaryngol Head Neck Surg. 1985 Apr;93(2):146-7.
http://www.ncbi.nlm.nih.gov/pubmed/3921901?tool=bestpractice.com
The House-Brackmann scale is a grading tool developed by two neuro-otologists to assist with facial nerve evaluation after lateral skull base surgery.[17]House JW, Brackmann DE. Facial nerve grading system. Otolaryngol Head Neck Surg. 1985 Apr;93(2):146-7.
http://www.ncbi.nlm.nih.gov/pubmed/3921901?tool=bestpractice.com
The scale is used widely to determine the severity of facial paralysis; however, it does not account for different degrees of severity between regions of the face, and does not adequately assess changes in facial symmetry after interventions.[18]Dusseldorp JR, van Veen MM, Mohan S, et al. Outcome tracking in facial palsy. Otolaryngol Clin North Am. 2018 Dec;51(6):1033-50.
http://www.ncbi.nlm.nih.gov/pubmed/30172554?tool=bestpractice.com
Classification using the scale is as follows:[17]House JW, Brackmann DE. Facial nerve grading system. Otolaryngol Head Neck Surg. 1985 Apr;93(2):146-7.
http://www.ncbi.nlm.nih.gov/pubmed/3921901?tool=bestpractice.com
Grade I = normal
Grade II = slight weakness/asymmetry
Grade III = obvious weakness with movement but absence of disfigurement at rest; intact ability to close the eye
Grade IV = obvious weakness with movement and disfigurement at rest; inability to fully close the eye
Grade V = barely perceptible movement
Grade VI = no movement.
Sunnybrook facial grading system[19]Ross BG, Fradet G, Nedzelski JM. Development of a sensitive clinical facial grading system. Otolaryngol Head Neck Surg. 1996 Mar;114(3):380-6.
http://www.ncbi.nlm.nih.gov/pubmed/8649870?tool=bestpractice.com
The Sunnybrook facial grading system is slightly more nuanced grading tool than the House-Brackmann scale and is preferred by facial palsy researchers.[19]Ross BG, Fradet G, Nedzelski JM. Development of a sensitive clinical facial grading system. Otolaryngol Head Neck Surg. 1996 Mar;114(3):380-6.
http://www.ncbi.nlm.nih.gov/pubmed/8649870?tool=bestpractice.com
[20]Fattah AY, Gurusinghe ADR, Gavilan J, et al. Facial nerve grading instruments: systematic review of the literature and suggestion for uniformity. Plast Reconstr Surg. 2015 Feb;135(2):569-79.
http://www.ncbi.nlm.nih.gov/pubmed/25357164?tool=bestpractice.com
[21]Berner JE, Kamalathevan P, Kyriazidis I, et al. Facial synkinesis outcome measures: A systematic review of the available grading systems and a Delphi study to identify the steps towards a consensus. J Plast Reconstr Aesthet Surg. 2019 Jun;72(6):946-63.
http://www.ncbi.nlm.nih.gov/pubmed/30928304?tool=bestpractice.com
It consists of ordinal-scale scoring of multiple parameters within three domains:[19]Ross BG, Fradet G, Nedzelski JM. Development of a sensitive clinical facial grading system. Otolaryngol Head Neck Surg. 1996 Mar;114(3):380-6.
http://www.ncbi.nlm.nih.gov/pubmed/8649870?tool=bestpractice.com
Resting symmetry (eye, nasolabial fold, and mouth)
Symmetry of voluntary movement (brow elevation, gentle eye closure, open mouth smile, snarl, and lip pucker)
Synkinesis (same parameters as voluntary movement).
Sunnybrook facial grading system domain scores are combined to form a weighted composite score from 0 (complete flaccid paralysis) to 100 (normal function).[19]Ross BG, Fradet G, Nedzelski JM. Development of a sensitive clinical facial grading system. Otolaryngol Head Neck Surg. 1996 Mar;114(3):380-6.
http://www.ncbi.nlm.nih.gov/pubmed/8649870?tool=bestpractice.com
While the complexity of the grading scale typically requires use of a paper or digital form for scoring and documentation, its use permits tracking of clinical recovery with higher precision over time, making it better suited for research use compared with the House-Brackmann scale.[19]Ross BG, Fradet G, Nedzelski JM. Development of a sensitive clinical facial grading system. Otolaryngol Head Neck Surg. 1996 Mar;114(3):380-6.
http://www.ncbi.nlm.nih.gov/pubmed/8649870?tool=bestpractice.com
Electronic facial paralysis assessment (eFACE)[22]Banks CA, Bhama PK, Park J, et al. Clinician-graded electronic facial paralysis assessment: the eFACE. Plast Reconstr Surg. 2015 Aug;136(2):223e-230e.
http://www.ncbi.nlm.nih.gov/pubmed/26218397?tool=bestpractice.com
The eFACE is a grading system that allows for comparative scoring across time, and for high fidelity analysis by incorporating variation in paralysis between regions of the face.[22]Banks CA, Bhama PK, Park J, et al. Clinician-graded electronic facial paralysis assessment: the eFACE. Plast Reconstr Surg. 2015 Aug;136(2):223e-230e.
http://www.ncbi.nlm.nih.gov/pubmed/26218397?tool=bestpractice.com
It consists of clinician-graded continuous visual analogue scales within three domains:[22]Banks CA, Bhama PK, Park J, et al. Clinician-graded electronic facial paralysis assessment: the eFACE. Plast Reconstr Surg. 2015 Aug;136(2):223e-230e.
http://www.ncbi.nlm.nih.gov/pubmed/26218397?tool=bestpractice.com
Static symmetry (resting brow, resting palpebral fissure width, resting nasolabial fold depth, oral commissure resting position)
Dynamic symmetry (brow elevation, gentle and full eye closure, nasolabial fold depth and orientation with smile, oral commissure excursion with smile, lower lip movement with 'eeeee' [the photographer will ask the person to say 'eeeee' when capturing movement of the lower lip])
Synkinesis (ocular, midfacial, mentalis, platysmal).
The tool is available as a downloadable application with a graphical user interface that allows for touch-screen scoring and, when linked to a database, immediate graphical comparison to previous scores. This grading tool has also been validated for use with standardised patient photos and videos.[23]Malka R, Miller M, Guarin D, et al. Reliability between in-person and still photograph assessment of facial function in facial paralysis using the eFACE facial grading system. Facial Plast Surg Aesthet Med. 2021 Sep;23(5):344-9.
http://www.ncbi.nlm.nih.gov/pubmed/33325774?tool=bestpractice.com
[24]Banks CA, Jowett N, Hadlock TA. Test-retest reliability and agreement between in-person and video assessment of facial mimetic function using the eFACE facial grading system. JAMA Facial Plast Surg. 2017 May 1;19(3):206-11.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5815128
http://www.ncbi.nlm.nih.gov/pubmed/28006048?tool=bestpractice.com
One systematic review concluded that eFACE was the most comprehensive tool available for the assessment of blink function.[25]Zaidman M, Novak CB, Borschel GH, et al. Assessment of eye closure and blink with facial palsy: a systematic literature review. J Plast Reconstr Aesthet Surg. 2021 Jul;74(7):1436-45.
http://www.ncbi.nlm.nih.gov/pubmed/33952434?tool=bestpractice.com