Line-field confocal optical coherence tomography: A new in vivo assessment tool for cutaneous mycosis fungoides

Line-Field Confocal Optical Coherence Tomography Imaging of Psoriasis With Histopathology Correlation

Line-field confocal optical coherence tomography (LC-OCT) is a novel imaging technique for in vivo examination of the skin that has recently been introduced in the dermatologic armamentarium of non-invasive diagnostic tools. Its usefulness in the diagnosis and treatment monitoring of some neoplastic, inflammatory, and infectious skin conditions has been demonstrated. The aim of this study was to evaluate the LC-OCT features of psoriasis in a large number of psoriatic plaques along with their histopathologic correlation. In this retrospective study, the LC-OCT and the corresponding histopathologic images of 100 psoriatic plaques of the trunk, upper and lower arms from 60 patients that underwent both procedures were evaluated and correlated. The following microscopic findings, typical of plaque psoriasis, were observed at both LC-OCT and histopathology: hyperkeratosis, parakeratosis, acanthosis, papillomatosis and vascular changes, Munro microabscesses, and pustules of Kogoj. The LC-OCT findings perfectly matched with histopathology. Our study confirms the usefulness of this new imaging technique in the non-invasive visualization of the common diagnostic clues of psoriasis.

Line-Field Confocal Optical Coherence Tomography: A New Skin Imaging Technique Reproducing a "Virtual Biopsy" with Evolving Clinical Applications in Dermatology

BACKGROUND

Line-field confocal optical coherence tomography is a novel technology able to reproduce a "virtual biopsy" of the skin. The aim of this review is to explore the application of line-field confocal optical coherence tomography (LC-OCT) in various skin diseases, covering skin cancers, inflammatory and infectious skin diseases, genetic diseases, cosmetic procedures, and less common disorders.

METHODS

Study selection was conducted based on LC-OCT and using pertinent MeSh terms, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines from inception to March 2024; to evaluate the quality and risk of bias of studies, Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was used.

RESULTS

the search retrieved 154 papers according to the selection criteria; after removing publications by one or more of the exclusion criteria, a total of 96 studies were found to be suitable for the analysis.

CONCLUSIONS

Increasing evidence supports the use of LC-OCT as an adjunctive diagnostic tool for the in vivo diagnosis of a variety of skin tumors. As this device can be considered a "bridge" between dermoscopy and histopathology, widening applications in numerous fields of clinical dermatology, including inflammatory skin disease treatment, presurgical mapping, cosmetic procedures, and monitoring of non-invasive therapies, have been explored.

Preliminary Experience in Ultra-High Frequency Ultrasound Assessment of Cutaneous Primary Lymphomas: An Innovative Classification

BACKGROUND

Primary cutaneous lymphoma (PCL) is a rare form of extranodal non-Hodgkin's lymphoma characterized by malignant lymphocytes confined to the skin. Accurate diagnosis and staging are crucial for optimal management, yet radiological literature on imaging PCL remains limited. This study aims to delineate the imaging characteristics of PCLs using high and ultra-high frequency ultrasound (UHFUS) and proposes a classification system based on ultrasound findings.

METHODS

A cohort of 88 individuals with suspected PCL underwent high-resolution ultrasound (HRUS) and color Doppler examination of lesions. Lesions were categorized based on sonographic appearance, and subsequent histopathological assessment confirmed the diagnosis.

RESULTS

Ultrasound imaging revealed distinct patterns for primary cutaneous T-cell lymphomas (PCTCL) and primary cutaneous B-cell lymphomas (PCBCL), with characteristic features such as hypoechoic nodules, pseudonodular lesions, and dermal infiltration. Histopathological analysis confirmed the ultrasound findings, supporting the proposed classification system.

CONCLUSIONS

Ultrasonography, particularly UHFUS, offers valuable insights into the imaging characteristics of primary cutaneous lymphomas, aiding the accurate diagnosis and assessment of treatment response. The proposed classification system based on ultrasound findings enhances the diagnostic approach to PCLs, and paves the way for improved patient care and management strategies.

Features of tattoo-associated cutaneous lymphoid hyperplasia on reflectance confocal microscopy and line-field confocal optical coherence tomography

The popularity of tattoos has led to an increase in associated skin reactions, including complications such as infection, allergic reactions and rare conditions such as tattoo-induced cutaneous lymphoid hyperplasia (CLH). CLH is a benign lymphoproliferative reaction with clinical features resembling malignant cutaneous lymphomas. Non-invasive diagnostic tools like reflectance confocal microscopy (RCM) and the new line-field confocal optical coherence tomography (LC-OCT) are being studied in dermatology better to understand the morphological patterns of many dermatological diseases. Between September 2021 and May 2023, patients with suspicious lesions for tattoo-related CLH were analysed using RCM and LC-OCT before confirming the diagnosis of CLH through skin biopsy and histopathological examination. The study included five cases of CLH. It focused on the analysis of high-quality LC-OCT images/videos and RCM images to investigate the features of CLH in tattooed individuals. Most (80%) cases exhibited a mixed T and B lymphocyte infiltration subtype, while 20% showed a predominant T infiltration subtype. RCM and LC-OCT revealed characteristic features, including architectural disarray, fibrosis, lymphoid infiltrates, and pigment deposits in the epidermis and dermis. Non-invasive tools such as RCM and LC-OCT are valuable in diagnosing tattoo-related CLH. While skin biopsy remains the current standard for diagnosis, RCM and LC-OCT can serve as helpful adjuncts in identifying the most representative area for biopsy. They may potentially become alternative diagnostic options in the future, offering benefits in terms of cost, diagnostic efficiency, aesthetics and patient satisfaction as the prevalence of tattoo-related adverse reactions continues to rise.