Photoacoustic Imaging of Tattoo Inks: Phantom and Clinical Evaluation

Abstract

Photoacoustic imaging (PAI) is a novel hybrid imaging modality that provides excellent optical contrast with the spatial resolution of ultrasound in vivo. The method is widely being investigated in the clinical setting for diagnostic applications in dermatology. In this report, we illustrate the utility of PAI as a non-invasive tool for imaging tattoos. Ten different samples of commercially available tattoo inks were examined for their optoacoustic properties in vitro. In vivo PAI of an intradermal tattoo on the wrist was performed in a healthy human volunteer. Black/gray, green, violet, and blue colored pigments provided higher levels of PA signal compared to white, orange, red, and yellow pigments in vitro. PAI provided excellent contrast and enabled accurate delineation of the extent of the tattoo in the dermis. Our results reveal the photoacoustic properties of tattoo inks and demonstrate the potential clinical utility of PAI for intradermal imaging of tattoos. PAI may be useful as a clinical adjunct for objective preoperative evaluation of tattoos and potentially to guide/monitor laser-based tattoo removal procedures.

Picosecond Q-Switched 1064/532 nm Laser in Tattoo Removal: Our Single Center Experience

“…However, these results may be biased because picosecond sources are often used for harder-to-treat tattoos, such as professional tattoos with mixed colors. Photoacoustic imaging may be useful as a clinical adjunct for the objective preoperative evaluation of tattoos and potentially as a guide/monitor for laser-based tattoo removal procedures [31].…”

Clinical noninvasive imaging and spectroscopic tools for dermatological applications: Review of recent progress

“…There are emerging dermatological applications which can benefit from PAI. For example, Bolookat et al demonstrated that tattoo inks are PA active and the delineation of the shape of an in vivo intradermal tattoo can be visualized by PAI [55]. PAI can potentially be exploited in the preoperative evaluation of tattoos before its laser removal process and in guiding the removal process by objectively visualizing remaining tattoo inks in the dermal region.…”

Diffused reflectance measurements to detect tattoo ink location in skin using the crossover point

“…In this paper, an introductory tattoo study was conducted on synthetic tattoos made on 2L tissue‐like PDMS phantoms. Tattoo ink absorbs the light and reflects the light [13], while DR measures the re‐emitted light. From this re‐emittance, we calculated the absorption coefficients of the 2L phantom based on the Cp.…”

“…Several imaging techniques, such as two‐photon microscopy [11], X‐ray computed tomography [12], photoacoustic imaging (PAI) [13], optical coherence tomography (OCT) [14], and Raman microscopy [15] are excellent for determining the chemical composition of tattoo ink. However, these methods are limited in penetration depth, because tattoo ink is mainly present in the dermal layer (~2.0 to 4 mm) of the skin [16].…”