Inverse psoriasis represents a clinical variant of psoriasis that is sometimes difficult to diagnose due to its clinical similarity with other skin disorders involving the folds, mainly including mechanical intertrigo, fungal and bacterial infections, contact dermatitis, seborrheic dermatitis, and lichen planus. Dermoscopy represents a useful tool for an enhanced non-invasive diagnosis. The treatment of inverse psoriasis may be challenging and include topical corticosteroids, topical calcineurin inhibitors, vitamin D analogs, traditional oral systemic therapies such as cyclosporine and methotrexate, and biologic therapies.

Background: Line‐field confocal optical coherence tomography (LC‐OCT) is a novel, non‐invasive technique that provides in vivo, high‐resolution images in both vertical and horizontal sections.Objectives: The aim of the study was to evaluate LC‐OCT imaging in some inflammatory disorders and to correlate the resulting features with histopathology.Methods: The retrospective study included patients with histopathological confirmed diagnosis of plaque psoriasis, atopic eczema and lichen planus, who were imaged with LC‐OCT before the biopsy. LC‐OCT was performed with the commercially available LC‐OCT device.Results: A total of 15 adult patients with histopathologically proven plaque psoriasis (N: 5), atopic eczema (N: 5) and lichen planus (N: 5) were included. In all cases, LC‐OCT allowed the in vivo recognition of the main microscopic features of the examined inflammatory skin disease, with a strong correlation with histopathology.Conclusions: Although future studies on larger series of patients are necessary, LC‐OCT, based on these preliminary findings, may represent a promising tool in inflammatory skin disorders with potential applications including enhanced diagnosis, biopsy guidance, follow‐up and treatment monitoring.

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.

Line-field confocal optical coherence tomography (LC-OCT) is a novel, non-invasive technique for real-time skin imaging. Imiquimod (IQ) 5% cream is an immune response modifier currently approved for the treatment of small, superficial basal cell carcinoma (BCC). The aim of this study was to investigate if LC-OCT may be useful to enhance the treatment monitoring of BCC. Twenty superficial BCCs from 12 patients were treated with IQ 5% cream once daily, five days a week, for six weeks. Clinical and LC-OCT evaluations were performed at baseline and 4 weeks after the end of treatment. At the end of the study, 13 lesions showed a complete clinical and LC-OCT response, 4 lesions a partial clinical and LC-OCT response, and 3 lesions a complete clinical response but residual tumoral signs at LC-OCT. Our pilot study suggests that LC-OCT may represent a promising tool able to enhance the evaluation of the treatment response of BCCs to non-invasive treatments. In our case series, its use highlighted, through a detailed, fast, and complete examination of the treated area, three cases of residual BCC that otherwise would have gone undetected at clinical examination. Future studies on larger series of patients treated with different modalities and with a longer follow-up are advisable.