Polarization Sensitive Optical Coherence Tomography: A Review of Technology and Applications

Abstract

Polarization sensitive optical coherence tomography (PS-OCT) is an imaging technique based on light scattering. PS-OCT performs rapid two-and three-dimensional imaging of transparent and translucent samples with micrometer scale resolution. PS-OCT provides image contrast based on the polarization state of backscattered light and has been applied in many biomedical fields as well as in non-medical fields. Thereby, the polarimetric approach enabled imaging with enhanced contrast compared to standard OCT and the quantitative assessment of sample polarization properties. In this article, the basic methodological principles, the state of the art of PS-OCT technologies, and important applications of the technique are reviewed in a concise yet comprehensive way.

Detection of carious lesions utilizing depolarization imaging by polarization sensitive optical coherence tomography

“…6,11,15 On the other hand, the utilization of the DOPU algorithm in combination with PS-OCT is an established concept in ophthalmologic research. 8,16,18 To the best of our knowledge, this is the first time that the DOPU algorithm is applied for the detection of carious lesions in dentistry. We consider it as a promising method for the identification and delimitation of early carious lesions in particular but also the assessment of the severity of an undermining caries and a cavity.…”

“…This includes polarization sensitive imaging and the consequent measurement of depthresolved birefringence, which until now has been applied in many biomedical as well as nonmedical fields. 8,9 In terms of hard dental tissue and caries detection, first polarization sensitive OCT (PS-OCT) measurements confirmed the birefringent properties of enamel and dentin, 4,10 and it was determined that demineralization, accompanying carious infections, results in depolarization of light. 11 Since then, several studies have shown the potential of PS-OCT to observe the internal structure and the remineralization of lesions, as well as an early detection of variously located caries.…”

In vivo imaging of human oral hard and soft tissues by polarization-sensitive optical coherence tomography

“…8 Today, this method is referred to as PS OCT with single circular input state, which provides quantitative polarization contrast for all possible optic axis orientations of the sample. 9 Beyond the technical advancements in terms of light sources and fast detection units, PS OCT was evolved by different detection schemes with multiple input states as well as improved data processing. Initially, 7,8 the reflectivity and retardation of a sample were measured for the determination of birefringence as a function of the depth.…”

“…[10][11][12] An additional relevant parameter, the degree of polarization uniformity (DOPU), is based on averaged Stokes vector elements and proposed for imaging and segmentation of local variations of the polarization state 13,14 also known as depolarization or rather polarization scrambling as an intrinsic tissue property. 15 Equipped with these advancements, PS OCT is increasingly applied for medical diagnosis mainly in ophthalmology 9,[16][17][18] followed by dentistry, 19,20 cardiology, 6,21,22 and dermatology [23][24][25] with regard to the frequency of publications over the last years. 9 Although PS OCT has successfully shown to provide additional contrast for distinguishing pathological lesions from normal tissues, it has not been used much in the oral cavity.…”

“…15 Equipped with these advancements, PS OCT is increasingly applied for medical diagnosis mainly in ophthalmology 9,[16][17][18] followed by dentistry, 19,20 cardiology, 6,21,22 and dermatology [23][24][25] with regard to the frequency of publications over the last years. 9 Although PS OCT has successfully shown to provide additional contrast for distinguishing pathological lesions from normal tissues, it has not been used much in the oral cavity. While the measurement of the birefringent behavior of hard dental tissues by PS OCT is already addressed in biomedical research, [26][27][28] the polarization properties of oral soft tissue ex vivo and in vivo are investigated only by a few studies, [29][30][31][32] although the presented results show that it is worthwhile for quantitative imaging.…”