Handheld optical coherence tomography-reflectance confocal microscopy probe for detection of basal cell carcinoma and delineation of margins.

Nicusor Iftimia,Aditi Sahu,Gopi Maguluri,Oriol Yélamos,Milind Rajadhyaksha,Christi Alessi-Fox,Chih-Shan J Chen,Miguel A Cordova,Jesung Park,William Fox

doi:10.1117/1.jbo.22.7.076006

Abstract

.We present a hand-held implementation and preliminary evaluation of a combined optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) probe for detecting and delineating the margins of basal cell carcinomas (BCCs) in human skin in vivo. A standard OCT approach (spectrometer-based) with a central wavelength of 1310 nm and 0.11 numerical aperture (NA) was combined with a standard RCM approach (830-nm wavelength and 0.9 NA) into a common path hand-held probe. Cross-sectional OCT images and enface RCM images are simultaneously displayed, allowing for three-dimensional microscopic assessment of tumor morphology in real time. Depending on the subtype and depth of the BCC tumor and surrounding skin conditions, OCT and RCM imaging are able to complement each other, the strengths of each helping overcome the limitations of the other. Four representative cases are summarized, out of the 15 investigated in a preliminary pilot study, demonstrating how OCT and RCM imaging may be synergistically combined to more accurately detect BCCs and more completely delineate margins. Our preliminary results highlight the potential benefits of combining the two technologies within a single probe to potentially guide diagnosis as well as treatment of BCCs.

Highlights

Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) are well-established optical imaging technologies, and their use, individually and independently, for the noninvasive diagnosis of nonmelanoma skin cancers (NMSCs) has been reported in several studies.[1,2,3,4] OCT imaging is similar to ultrasound but with much higher resolution, with 5 to 10 μm optical sectioning and to depths of at least 1 mm.[5]
RCM imaging provides 1 to 3 μm optical sectioning and 0.5 to 1.0 μm lateral resolution, which is on par with that of conventional pathology, but the depth of imaging is limited to about 200 μm.[6]
Out of the 12 basal cell carcinomas (BCCs) positive cases, both RCM and OCT clearly identified BCCs in nine cases, whereas in two cases, RCM identified BCCs, which was suspected but not clearly evident with OCT, and in one case, RCM was suspicious for a BCC that was unequivocally identified in the OCT mode

Summary

Introduction

Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) are well-established optical imaging technologies, and their use, individually and independently, for the noninvasive diagnosis of nonmelanoma skin cancers (NMSCs) has been reported in several studies.[1,2,3,4] OCT imaging is similar to ultrasound but with much higher (micron scale) resolution, with 5 to 10 μm optical sectioning and to depths of at least 1 mm.[5]. NMSCs are the most common skin malignancies in USA and in other areas of the world. Among NMSCs, basal cell carcinomas (BCCs) in particular, occur with the highest incidence rates and account for about 70% to 80% of the total NMSCs.[7,8] Not surprisingly, several OCT and RCM imaging studies have focused on noninvasive detection of BCCs, as a possible adjunct to clinical and dermoscopic examination and pathology. Studies report sensitivities and specificities in the range 80% to 95% and 70% to 90%, respectively, for both OCT and RCM.[1,2,3,4] Other studies have reported the ability of OCT and RCM imaging to delineate lateral margins of BCCs.[9,10,11] studies have reported the ability of OCT to reliably detect the depth

Methods

Results

Conclusion