WIFI SPATIAL MAPPING OF IN-VIVO TATTOO SKIN OPTICAL PROPERTIES

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 曾经只有一小部分人在社会上纹身，现在纹身已经变得更加常见。最近的一项调查显示，四分之一的美国人至少有一个纹身。随之而来的是纹身实践的增长，激光纹身去除的需求也增加了。同一项调查估计，在有纹身的人中，有17%的人考虑过去除纹身。激光去除纹身的黄金标准程序包括使用四种调Q激光中的一种，或组合使用波长为532 nm、694 nm、755 nm和1064 nm的激光。虽然激光去除纹身很有效，但它往往是一个昂贵和耗时的过程。业余纹身通常需要四到六次纹身才能达到几乎完全消除的效果。专业纹身使用更坚固的颜料，通常在真皮中放置的浓度较高，平均需要8-12次处理。在这两种情况下，治疗需要间隔四到六周。并发症包括由于周围组织过度吸收激光能量而导致的皮肤结垢或起泡，色素沉着过少和过度，以及由于二氧化钛或三氧化二铁的存在而导致的自发纹身变黑。理想情况下，治疗必须以最少的治疗次数移除纹身，同时将这些并发症降至最低。目前，激光的选择以及其他参数，如通量，是由临床医生根据定性观察和先前的临床经验来选择的。 大多数关于激光纹身去除效果的文献都是基于治疗的临床案例研究；然而，与纹身相关的光学信息可以用来提高治疗的效率。在20世纪90年代中期，Haedersdal等人。测量纹身皮肤从300 nm到800 nm的光谱反射率，以确定几种颜色的最大吸收范围。这项研究包括了13个纹身，涉及14种不同的颜色，最常见的是红色和绿色。作者认为，光谱反射信息可以用来指导激光的选择，包括使用可调谐的固体激光来去除纹身。Baumler等人使用了波长从320 nm到1100 nm的分光光度计，测量了大量悬浮在溶剂中的商用颜料的吸收光谱。不幸的是，这不是一个实用的方法来指导激光纹身去除，因为有更多的染料可用。纹身中的颜色通常是由最初的纹身艺术家选择并仅为其所知的各种颜料的组合。此外，工作台光谱学不提供诸如降低的散射系数或底层皮肤的光学属性之类的信息。最近，O？Goshi等人使用共聚焦扫描激光显微镜来显示纹身的颗粒大小和密度。这项技术只在一个波长扫描，不能提供快速的广域光谱特性映射。在这个项目中，我们使用调制成像技术测量纹身的吸收和散射光谱，这是一种新的广域光谱成像方式。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Once practiced by a small portion of society, skin tattooing has become more common place. A recent survey suggests that 1 in 4 Americans has at least one tattoo. Following this growth in the practice of tattooing has been an increase in demand for laser tattoo removal. The same survey estimated that 17% of those with a tattoo had considered removing it. The gold standard procedure for laser tattoo removal involves the use of one of four, or a combination of, Q-switched lasers operating at wavelengths of 532nm, 694nm, 755nm, and 1064nm. While laser tattoo removal has been effective, it is often an expensive and time consuming process. Amateur tattoos often require four to six sessions to affect near complete erasure. Professional tattoos, which use more robust pigments and are generally placed at higher concentrations in the dermis, require an average of 8-12 treatments. In both cases treatments need to be spaced over four to six weeks. Complications include skin scaling or blistering due to excessive absorption of laser energy by the surrounding tissue, hypo and hyper pigmentation, and spontaneous tattoo darkening due to the presence of titanium oxide or ferric oxide. Ideally, treatment must remove the tattoo with the fewest number of treatments while minimizing these complications. Currently laser selection, as well as other parameters such as fluence, is chosen by the clinician based on qualitative observation and previous clinical experience. The majority of literature involving laser tattoo removal effectiveness has been based on clinical case studies of treatments; however, tattoo related optical information could be used to improve the efficiency of the treatment. In the mid 1990s, Haedersdal et al. measured the spectral reflectance of tattooed skin from 300nm to 800nm to establish ranges of maximum absorption for several colors. Thirteen tattoos involving fourteen different colors, the most common being red and green, were included in the study. The authors suggested that spectral reflectance information could be used to guide laser selection including the use of tunable solid state lasers for tattoo removal. Baumler et al used a spectrophotometer over the wavelength 320nm to 1100nm to measure the absorption spectra of a large number of commercially available pigments suspended in solvent. Unfortunately this is not a practical method for guiding laser tattoo removal because of the even larger number of dyes available. Colors in a tattoo are often a combination of pigments chosen by and known only to the original tattoo artist. Also, bench top spectroscopy does not provide information such as a reduced scattering coefficient or the optical properties of the underlying skin. Most recently, O¿¿"goshi et al used confocal scanning laser microscopy to visualize the particle size and density of a tattoo. This technology scans at a single wavelength and cannot provide rapid wide-field mapping of spectral properties. In this project we meausure absorption and scattering spectra for tattoos using Modulated Imaging, a new wide-field spectral imaging modality.