Diagnostic Accuracy of Line-Field Confocal Optical Coherence Tomography for the Diagnosis of Skin Carcinomas
Line-field confocal optical coherence tomography (LC-OCT) is a new, noninvasive imaging technique for the diagnosis of skin cancers. A total of 243 benign (54%) and malignant (46%) skin lesions were consecutively enrolled from 27 August 2020, to 6 October 2021 at the Dermatology Department of the University Hospital of Siena, Italy. Dermoscopic- and LC-OCT-based diagnoses were given by an expert dermatologist and compared with the ground truth. Considering all types of malignant skin tumours (79 basal cell carcinomas (BCCs), 22 squamous cell carcinomas, and 10 melanomas), a statistically significant increase (p = 0.013) in specificity was observed from dermoscopy (0.73, CI 0.64–0.81) to LC-OCT (0.87, CI 0.79–0.93) while sensitivity was the same with the two imaging techniques (0.95 CI 0.89–0.98 for dermoscopy and 0.95 CI 0.90–0.99 for LC-OCT). The increase in specificity was mainly driven by the ability of LC-OCT to differentiate BCCs from other diagnoses. In conclusion, our real-li...
Diagnostics Using Non-Invasive Technologies in Dermatological Oncology
The growing incidence of skin cancer, with its associated mortality and morbidity, has in recent years led to the developing of new non-invasive technologies, which allow an earlier and more accurate diagnosis. Some of these, such as digital photography, 2D and 3D total-body photography and dermoscopy are now widely used and others, such as reflectance confocal microscopy and optical coherence tomography, are limited to a few academic and referral skin cancer centers because of their cost or the long training period required. Health care professionals involved in the treatment of patients with skin cancer need to know the implications and benefits of new non-invasive technologies for dermatological oncology. In this article we review the characteristics and usability of the main diagnostic imaging methods available today.
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Morphologic evaluation of melanocytic lesions with three-dimensional line-field confocal optical coherence tomography: correlation with histopathology and reflectance confocal microscopy. A pilot study
Background Line-field confocal optical coherence tomography (LC-OCT) is a new in vivo emerging technique which provides cellular resolution, imaging depth (400 μm) and produces real-time images in both the horizontal and vertical plane and in 3 dimensions (3D). No previous description of different subtypes of melanocytic lesions and their correlation with histopathology and reflectance confocal microscopy has been reported. Objectives We aimed to describe the features of melanocytic lesions by LC-OCT and their correlation with histopathology and reflectance confocal microscopy (RCM). Methods Selected melanocytic benign lesions and melanomas were imaged in vivo with RCM and LC-OCT at the Hospital Clinic of Barcelona. A minimum area of 4mm x 4mm (block image) at 4 depths (stratum granulosum, suprabasal, dermoepidermal-junction and upper dermis) were acquired with RCM and a minimum of 3 cubes with LC-OCT. Horizontal, vertical sections and 3D cubes of LC-OCT were matched with RCM Viv...
Non-invasive scoring of cellular atypia in keratinocyte cancers in 3D LC-OCT images using Deep Learning
Diagnosis based on histopathology for skin cancer detection is today's gold standard and relies on the presence or absence of biomarkers and cellular atypia. However it suffers drawbacks: it requires a strong expertise and is time-consuming. Moreover the notion of atypia or dysplasia of the visible cells used for diagnosis is very subjective, with poor inter-rater agreement reported in the literature. Lastly, histology requires a biopsy which is an invasive procedure and only captures a small sample of the lesion, which is insufficient in the context of large fields of cancerization. Here we demonstrate that the notion of cellular atypia can be objectively defined and quantified with a non-invasive in-vivo approach in three dimensions (3D). A Deep Learning (DL) algorithm is trained to segment keratinocyte (KC) nuclei from Line-field Confocal Optical Coherence Tomography (LC-OCT) 3D images. Based on these segmentations, a series of quantitative, reproducible and biologically relevant...
Line-field confocal optical coherence tomography of actinic keratosis: a case series
Line-field confocal optical coherence tomography (LC-OCT) is a non-invasive imaging technique that was recently developed, combining high penetration depth (up to 500-µm, approaching that of conventional OCT) with high isotropic resolution [lateral: 1.3 µm; axial: 1.1 µm - similar to that of reflectance confocal microscopy (RCM)]. 1 .
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Line-field confocal optical coherence tomography of sebaceous hyperplasia: a case series
Line-field confocal optical coherence tomography (LC-OCT) is a newly developed non-invasive imaging technique that combines high penetration depth (500 µm, similar to conventional OCT) with high isotropic resolution (lateral 1.3 µm, axial 1.1 µm, similar to reflectance confocal microscopy [RCM]). 1 Moreover, with its ability to produce images in both vertical and horizontal planes, it enables a tridimensional (3D) analysis of the skin, which can prove very useful for assessing physiological 2 as well as pathological skin.
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Line-field confocal optical coherence tomography for high-resolution noninvasive imaging of skin tumors
An optical technique called line-field confocal optical coherence tomography (LC-OCT) is introduced for high-resolution, noninvasive imaging of human skin in vivo . LC-OCT combines the principles of time-domain optical coherence tomography and confocal microscopy with line illumination and detection using a broadband laser and a line-scan camera. LC-OCT measures the echo-time delay and amplitude of light backscattered from cutaneous microstructures through low-coherence interferometry associated with confocal spatial filtering. Multiple A-scans are acquired simultaneously while dynamically adjusting the focus. The resulting cross-sectional B-scan image is produced in real time at 10 frame / s. With an isotropic spatial resolution of ∼1 μm, the LC-OCT images reveal a comprehensive structural mapping of skin at the cellular level down to a depth of ∼500 μm. LC-OCT has been applied to the imaging o...
Methods of Melanoma Detection
Detection and removal of melanoma, before it has metastasized, dramatically improves prognosis and survival. The purpose of this chapter is to (1) summarize current methods of melanoma detection and (2) review state-of-the-art detection methods and technologies that have the potential to reduce melanoma mortality. Current strategies for the detection of melanoma range from population-based educational campaigns and screening to the use of algorithm-driven imaging technologies and performance of assays that identify markers of transformation. This chapter will begin by describing state-of-the-art methods for educating and increasing awareness of at-risk individuals and for performing comprehensive screening examinations. Standard and advanced photographic methods designed to improve reliability and reproducibility of the clinical examination will also be reviewed. Devices that magnify and/or enhance malignant features of individual melanocytic lesions (and algorithms that are availab...
In Vivo Noninvasive Imaging of Healthy Lower Lip Mucosa: A Correlation Study between High-Definition Optical Coherence Tomography, Reflectance Confocal Microscopy, and Histology
In recent years, technology has allowed the development of new diagnostic techniques which allow real-time, in vivo , noninvasive evaluation of morphological changes in tissue. This study compares and correlates the images and findings obtained by high-definition optical coherence tomography (HD-OCT) and reflectance confocal microscopy (RCM) with histology in normal healthy oral mucosa. The healthy lip mucosa of ten adult volunteers was imaged with HD-OCT and RCM. Each volunteer was systematically evaluated by RCM starting in the uppermost part of the epithelium down to the lamina propia. Afterwards, volunteers were examined with a commercially available full-field HD-OCT system using both the “slice” and the “en-face” mode. A “punch” biopsy of the lower lip mucosa was obtained and prepared for conventional histology. The architectural overview offered by “slice” mode HD-OCT correlates with histologic findings at low magnification. In ...