P1.057: Topical Lidocaine or not for laser follicle ablation in pilonidal disease: a prospective, randomized, double-blinded trial

Background: Laser follicle ablation is a significant component of the care in pilonidal disease but may be uncomfortable secondary to absorption of the light energy by pigment present in the underlying skin. Multiple methods have been proposed to ameliorate the discomfort, including the pre-procedure application of topical lidocaine creams, however, little data exists as to the efficacy of the creams, which must be applied 30 to 40 minutes prior to laser treatment. We studied the efficacy of a topical local anesthetic cream (LMX; lidocaine 4%) for this purpose.

Methods: A prospective, double-blinded randomized controlled trial was conducted and included patients presenting to the pilonidal care clinic for laser follicle ablation. Power calculation was based on a superiority design where a sample size of 20 participants had 80% power to detect a standardized difference of 0.67 in pain scores between treatments (difference in means = 2 and standard deviation = 3) using a paired-test with 5% alpha. Patients were randomized assigned to receive topical anesthetic cream or placebo and crossed over between study arms to serve as their own control for their subsequent laser follicle ablation, 6 to 8 weeks later. The topical cream remained applied to each patients’ gluteal crease for 30 to 40 minutes prior to laser follicle ablation after which the cream was removed and the patient was asked their level of discomfort with the laser follicle ablation using cold air on a 0-10 Likert pain scale.

Results: Twenty-two patients were recruited to participate, 2 of whom did not return for their next clinic visit, 1 secondary to a snowstorm and the other secondary to insurance issues, leaving 20 patients for analysis. The mean age was 20 years (range: 15 to 32), including 11 males (55%). The mean pain score with LMX was 2.25 (SD 1.94), placebo 1.78 (SD 1.15) (p = 0.18; figure 1). There were no noted complications.

Conclusion: Application of topical anesthetic cream adds significant time to a patient’s clinic visit and does not appear to improve pain control when compared to placebo for gluteal laser follicle ablation for pilonidal disease.