Measuring outcomes in facial palsy treatment: adding extra dimensions to a complex matter.

The human face is crucial in social interaction and demonstrates cues of health, trustworthiness, emotions, and much more. A peripheral facial palsy (PFP) refers to a lower motor neuron lesion of the facial nerve and, due to its anatomy, could have many etiologies, such as traumatic, idiopathic, infectious, and oncological. Approximately 30% are left with long-term sequelae and 4% with severe dysfunction. For facial plastic surgeons, a PFP represents a great reconstructive challenge. It is a debilitating condition with functional (corneal exposure, epiphora, oral incompetence, and nasal obstruction, among others) and aesthetic sequelae that often result in physical, psychosocial, communicative, and quality-of-life losses. It remains the question how we measure the effects of the treatment of patients with a facial palsy, since there are many variety in cosmetic appreciation, surgical goals, patients' needs, and measuring tools. The aims of this narrative review are: 1) to give an overview of conservative measuring and classification tools, 2) clinician-graded instruments versus patient-graded instruments, and 3) which domains should be considered when assessing effects of our treatment. Level of evidence: Not gradable. [ABSTRACT FROM AUTHOR]