Evaluation of Device-Based Cutaneous Channels Using Optical Coherence Tomography: Impact for Topical Drug Delivery

Topical medications play a large role in the management of cutaneous diseases, but penetration is limited. Device-assisted drug delivery using mechanical destruction, lasers, and other energy-based modalities can increase penetration and absorption through creation of transcutaneous channels.

To examine real-time, in vivo cutaneous changes in response to various devices used to improve topical drug delivery through optical coherence tomography (OCT) imaging.

Treatment was performed with 8 medical devices, including mechanical destruction, lasers, and other energy-based modalities. Optical coherence tomography was used for real-time, noninvasive, in vivo imaging.

Using OCT, microneedling and radiofrequency microneedling demonstrated no cutaneous channels. Both low-energy, low-density, fractional nonablative lasers produced transient channels, which closed within hours. The fractional nonablative 1,927-nm thulium fiber and 1,550-nm erbium fiber lasers created channels with epidermal debris within, which were still closing at 24 hours. The fractional thermomechanical ablative device and the fractional ablative CO2 laser produced channels that were still open at 24 hours. CO2 laser channels had thick rims of coagulated tissue and remained open for longer.

Demonstrable differences among the devices were seen, and only some can produce observable channels, the characteristics of which vary with each technology.