Development and Validation of a Photonumeric Scale for Evaluation of Lip Fullness

March 2023 | Volume 22 | Issue 3 | 274 | Copyright © March 2023


Published online February 22, 2023

Jason D. Bloom MDa, Jonathan Kaplan MDb, Amit Verma DrPH MPHc, Ashlee W. Duncan MS PhDd

aPrivate practice, Bryn Mawr, PA
bPrivate practice, San Francisco, CA
cFormerly Global Clinical Development, Merz North America, Raleigh, NC (currently ABK Biomedical, Halifax, NS Canada)
dGlobal Clinical Development, Merz North America, Raleigh, NC

Abstract
Background: The shape, proportion, and fullness of one's lips are associated with overall facial beauty and attractiveness. Lip augmentation, due to personal preference or to reverse natural aging, has become a standard clinical procedure to improve lip volume or proportion. Several options are available to redefine the lips. To objectively evaluate treatment-related improvements in clinical practice and research, a validated photonumeric scale is needed.
Objective: To present scale-development methods for the Merz Lip Fullness Assessment Scale (MLFAS) and establish its reliability.
Methods: A 5-point photonumeric scale was developed to objectively assess loss of lip volume using male and female subjects of various ages and skin types. To establish intra- and interrater reliability, 8 board-certified dermatologists and plastic surgeons evaluated 64 subjects live in 2 sessions, 2 weeks apart.
Results: The weighted kappa for intra- and interrater agreement were ≥ 0.6 in all cases. Intrarater agreement between the 2 rating sessions was nearly perfect (median weighted kappa = 0.911 and 0.930 for the upper lip and lower lip, respectively). Substantial interrater agreement between each rater pair was also demonstrated for both rating sessions, and ratings of upper and lower lip fullness showed comparable reliability.
Conclusion: The MLFAS is a validated and reliable photonumeric scale for rating loss in lip volume. The scale maintains its reliability with reproducible results across a diverse group of males and females of various ages and Fitzpatrick skin types.

J Drugs Dermatol. 2023;22(3): doi:10.36849/JDD.7309

Citation: Bloom J, Kaplan J, Verma A, et al. Development and validation of a photonumeric scale for evaluation of lip fullness. J Drugs Dermatol. 2023;22(3):274-281. doi:10.36849/JDD.7309

INTRODUCTION

The lips are one part of an aesthetic unit that includes the teeth, gingiva, and bone structure of the face and contribute significantly to the overall impression of personal beauty.1-3 Specifically, fullness and delineation of the lips are associated with attractiveness, sensuality, and youth.2,4,5

Lip augmentation to correct volume deficits in the upper and/or lower lip has gained popularity, becoming a standard clinical procedure. Younger patients seeking lip augmentation may wish to add proportion and/or volume, while older patients may seek to reverse the lips' natural aging.6 Aging of the lips, attributed to breakdown of collagen support structures, is characterized by thinning of the upper and/or lower lip bodies; loss of delineated margins, projection, and color in the lips; lengthening of the upper lip; hanging or drooping corners of the mouth; and formation of the labiomental crease and wrinkles.5,7-10 Additional factors can intensify the changes associated with natural aging, including lifestyle, diet, genetics, smoking, stress, and exposure to the sun and pollution.1,5,9,11

Several noninvasive and minimally invasive techniques are available to increase lip volume and thickness, as well as correct surrounding wrinkles. Volume correction can be performed surgically via silicone implants, for example, or non-surgically. Among the available non-surgical procedures, dermal fillers are widely used and are highly suitable for lip augmentation and improvement of perioral wrinkles and lip contouring.5,12-14

Rising use of aesthetic facial fillers has driven the need for modern photonumeric scales to assess treatment response objectively and reproducibly by demonstrating aesthetic improvement from baseline. Concurrently, regulatory agencies have pressed for more robust validation measures of new aesthetic scales and established that these scales are fit-for-purpose in various clinical settings. Numerous facial-aging scales have been developed and validated over the past several years,15-27 and recent meta-analyses have compared over 100 such scales.28,29
Close Menu