ABSTRACT
Conventional and advance technologies are available for laser hair removal. Complete and permanent hair reduction is not yet possible by treatment with lasers. Ideal patient for any conventional laser hair removal treatment is one who has thick, dark terminal hair, light skin and normal hormonal status. Factors that contribute to variable outcomes in laser hair removal can be broadly divided into patient related ones and the technology related ones. Skin type, hair color, thickness and density, degree of tan, hormonal dysfunction etc., constitute the patient related factors. The wavelength, fluence, spot size and pulse duration of the laser system are the technology related factors. There are some patients who respond variably, unpredictably or poorly to laser hair removal despite ensuring that indication for treatment is appropriate with adequate parameters of the laser system. This article reviews various patient related and technology related factors which lead to variable-to-poor outcomes in laser hair removal; and various challenges and limitations of laser hair removal technology in patients with dark skin types.
ABSTRACT
Background: Tracking of various parameters associated with laser hair removal is tedious and time consuming. The currently available mathematical models are not simple enough for physicians to be used as a treatment optimization and patient education tool. Aim: The aim of the study was to develop a mathematical model for laser hair removal using agent-based modeling and to make a user-friendly simulation environment. Methods: The model was created using NetLogo. The hairs were modeled as agents oscillating between anagen and telogen. The variables were assigned based on published data whenever possible and the various paths the agent could take were coded as conditional statements. The improvement was assessed using an arbitrary index which takes into account the mean diameter and pigmentation along with the number and length of hairs visible above the surface. Few of the commonly encountered scenarios were simulated using the model. Results: The model is made freely available online (http://www.gulfdoctor.net/model/lhr.htm). Limited number of simulations performed indicated that an eight-week gap between laser sessions may be more effective than a four-week gap. Conclusions: The simulation provides a reliable tool for treatment optimization and patient education as obtaining relevant clinical data is slow and labor-intensive. Its visual interface and online availability makes it useful for everyday use.