Comparison of reflectance confocal microscopy and line‐field optical coherence tomography for the identification of keratinocyte skin tumours

Abstract

Background Reflectance confocal microscopy (RCM) and line‐field confocal optical coherence tomography (LC‐OCT) are non‐invasive imaging devices that can help in the clinical diagnosis of actinic keratosis (AK) and cutaneous squamous cell carcinoma (SCC). No studies are available on the comparison between these two technologies for the identification of the different features of keratinocyte skin tumours. Objectives To compare RCM and LC‐OCT findings in AK and SCC. Methods A retrospective multicenter study was conducted. Tumours were imaged with RCM and LC‐OCT devices before surgery, and the diagnosis was confirmed by histological examinations. LC‐OCT and RCM criteria for AK/SCC were identified, and their presence/absence was evaluated in all study lesions. Gwet AC1 concordance index was calculated to compare RCM and LC‐OCT. Results We included 52 patients with 33 AKs and 19 SCCs. Irregular epidermis was visible in most tumours and with a good degree of agreement between RCM and LC‐OCT (Gwet's AC1 0.74). Parakeratosis, dyskeratotic keratinocytes and both linear dilated and glomerular vessels were better visible at LC‐OCT than RCM (p < 0.001). Erosion/ulceration was identified with both methods in more than half of the cases with a good degree of agreement (Gwet AC1 0.62). Conclusions Our results suggest that both LC‐OCT and hand‐held RCM can help clinicians in the identification of AK and SCC, providing an in vivo and non‐invasive identification of an irregular epidermis. LC‐OCT proved to be more effective in identifying parakeratosis, dyskeratotic keratinocytes and vessels in this series.

Line‐field confocal optical coherence tomography: A new diagnostic method of lichen planopilaris

“…4,6 Line-field confocal optical coherence tomography (LC-OCT) is a new imaging technique that was recently developed to perform in vivo biopsy of the skin and mucosa with a resolution close to the histopathology examination. 7,8 LC-OCT combines the benefits of conventional optical coherence tomography (OCT) and reflectance confocal microscopy (RCM). It provides vertical images up to the depth of 5oo µm like conventional OCT.…”

“…LC-OCT permits to provide two-dimensional (2D) vertical and horizontal images as well as three-dimensional (3D) reconstructions. [7][8][9] Recent studies investigated the potential usefulness of reflectance confocal microscopy as a helpful diagnostic tool in lichen planopilaris. 10 Herein, we describe for the first time LC-OCT features of classic form of LPP.…”

Surgery after sonidegib treatment achieves complete response in locally advanced basal cell carcinoma of the face

“…At 12 months, line-field confocal optical coherence tomography (LC-OCT), a recently developed non-invasive imaging technique, was used to delinate the margins of the residual BCC. 7 The fact that the lesion was confined to a limited area allowed downstaging of the procedure from eye stage C to E, i.e., transfixing loss of substance of less than one quarter of the lower lid (Figure 1d). 4 The patient agreed to the excision of the residual BCC in the lateral canthus as it would not require surgical demolition and reconstruction of the lower tarsus.…”

Powell Lens-based Spectral Domain Line-Field Optical Coherence Tomography system for cellular resolution imaging of biological tissue

“…While the concept of LS-OCT was first proposed nearly two decades ago [5], it took more than a decade for suitable fast, 2D camera technology to be developed. Over the past ~10 years multiple research groups have developed LS-OCT for structural [6], vascular [7,8] and functional [9][10][11] imaging of the human retina, cellular resolution imaging of the human cornea and limbus [12], as well as cellular resolution imaging of human skin [13][14][15][16].…”