Pneumatic skin flattening (PSF): A novel technology for marked pain reduction in hair removal with high energy density lasers and IPLs

Abstract

PSF significantly reduces pain in all patients, even when higher (+30%) treatment energy levels are applied. Skin is well protected thermally by the conductive sapphire window. Post erythema and edema is considerably reduced, as well. Hair removal efficacy is preserved or enhanced. Treatment is faster and is uninterrupted by pain, without the necessity to apply topical anesthetic over a large area. Blood expulsion resulting from flattening the skin has also enabled the treatment of thin hair in light-skinned patients, using yellow and green wavelengths (540 nm cut-off filter) and short pulse durations with a higher efficacy than with the 650 nm cut-off filter.

Pneumatic skin flattening reduces pain during laser hair reduction

“…These authors also demonstrated decreased erythema posttreatment when using PSF, and reported that PSF resulted in equivalent or greater hair reduction than was noted without PSF use when evaluated post-treatment [16]. The likelihood that activating pressure receptors reduces the sensation of pain is supported by the fact that devices that produce pressure on the skin by vibration, but without suction, also reduce the sensation of pain felt during a procedure [15].…”

“…Lask et al [16] reported substantial pain reduction when using the PSF device and achieving 500 mm HG of negative pressure, and using the device with an IPL, 810 nm diode laser, and a 755 nm alexandrite laser for hair reduction. These authors also demonstrated decreased erythema posttreatment when using PSF, and reported that PSF resulted in equivalent or greater hair reduction than was noted without PSF use when evaluated post-treatment [16].…”

“…A relatively strong vacuum ensures more efficient compression of pressure receptors. Lask et al [16] previously demonstrated that the compression level should be above 400 millibars to achieve maximal pain reduction. The vacuum chamber consists of a plastic box covered with an optically coated sapphire window.…”

“…Sites were randomized as to which axilla received treatment using either the PSF device, or conventional treatment using the dynamic cooling device. Pain scores were based on a McGill Pain Questionnaire, which is commonly used in pain evaluation [13][14][15][16]. Using this scale, subjects graded pain according to a ten point scale with: 0-1 corresponding to the patient barely feeling the treatment pulses; 2-3 corresponding to the patient feeling Fig.…”

“…This device produces a pressure sensation on the skin thereby blocking the sensation of pain. This ability to substitute the sensation of pressure in the brain for pain is referred to as the gate theory of pain control [13][14][15][16][17]. The current study investigates the ability of the PSF device to affect pain during laser hair reduction, and its effect upon posttreatment side-effects and overall efficacy.…”