Development and validation of a photonumeric grading scale for assessing lip volume and thickness

BACKGROUND: Currently, there is the need of a validated grading scale for assessing lip volume/thickness. OBJECTIVE: The aim of this study was to assist clinicians in managing individuals seeking lip rejuvenation and to provide an objective method for evaluating the efficacy and longevity of such treatments. METHODS: Using accepted criteria for the development of dermatological grading scales, we have developed and validated a photographic grading scale for assessing lip volume and thickness based on digital parallel-polarized light imaging. RESULTS: The photographic grading scale was shown to be a valid and reliable instrument for assessing lip volume and thickness, with good inter- and intra-grader consistency. The validity of the scale was demonstrated by its correlation with clinical evaluation and 3-dimensional measurements. CONCLUSIONS: This validated lip-volume/thickness grading scale should prove helpful in clinical trial settings to standardize clinical evaluations and to quantify results and measure the longevity of dermal fillers and other procedures for lip rejuvenation.