Cutaneous Effects of Cryogen Spray Cooling on In Vivo Human Skin

Abstract

BACKGROUND Despite widespread clinical use of cryogen spray cooling (CSC) in conjunction with laser dermatologic surgery, in vivo cutaneous effects have not been systematically evaluated. OBJECTIVE The authors characterize the in vivo cutaneous effects for Fitzpatrick skin types I through VI after CSC exposures of varying spurt durations and spurt delivery patterns (single vs. multiple spurts). METHODS AND MATERIALS Twenty-seven normal human subjects were exposed to single cryogen spurts from 10 to 80 milliseconds, and multiple spurt patterns consisting of two 20-millisecond spurts, four 10-millisecond spurts, and eight 5-millisecond spurts. Subjects were evaluated by clinical observation and photography at 1 hour, 1 day, and 1, 4, 8, and 12 weeks after CSC exposure.

Complications of Vascular Laser Treatment

“…When used during laser treatment, cooling has multiple benefits including decreasing procedure related pain, allowing use of higher fluences, greater clinical effectiveness, safer use in patients with darker skin types, and decreased pigmentary changes, erythema, blistering, scarring, and purpura [3,10,11,18,19]. Three methods have been developed for epidermal cooling: contact, cooled air, and cryogen spray cooling.…”

“…Other errors can be made if there is misalignment of the laser/cryo-gen spray combination. Additionally, if the handpiece is not held perpendicular to the area to be treated, adequate cooling may not be achieved and crescent-shaped burn patterns may result [11,18]. Humidity in the air can lead to formation of an epidermal ice layer, which can attenuate the fluence by as much as 35% and produce backward scatter off of the ice surface [11].…”

Cryogen‐induced arcuate shaped hyperpigmentation by dynamic cooling device

“…Selective photothermolysis has revolutionized laser technology, and recently, lasers have been designed to deliver set wavelengths aimed at destroying targets with greater specificity and decreasing complications of scarring and pigmentary changes 1 . In addition, several cooling devices have been developed to reduce potential side effects 2–4 …”

“…A dynamic cooling device (DCD) is a safe and effective modality of selectively cooling the epidermis. Aerosol spurt application of liquid cryogen (1,1,1,2‐tetrafluoroethane, also known as R‐134a, Genetron 134a, or HFC‐134a) at the skin surface during or between laser pulse can minimize thermal injuries, decrease procedural‐associated pain, and allow the use of higher fluences 3,4 . However, even with recently developed laser treatments, there is always a risk of post‐inflammatory pigmentary alteration following any type of skin injuries, which is an especially important concern for patients with darker skin 3 .…”

“…The authors estimated the pigmentary complication rate to be from 0.5% to 3%, and among the seven mentioned patients, DCD caused ring or linear shaped dyspigmentation in four patients whose conditions resolved completely in 2 weeks to 5 months. Datrice et al 4 . described the results of a unique experiment on in vivo human skin with DCD to evaluate its potential cutaneous effects.…”