Hydradermabrasion through the lens of Line-Field Confocal Optical Coherence Tomography.

BACKGROUND: Hydradermabrasion, also known as "HydraFacial," is an exfoliative cosmetic procedure for skin rejuvenation that has gained popularity. Despite its increasing popularity, clinical studies validating its efficacy with non-invasive assessment of histological changes to the skin, are scarce. In this study, we used Line-Field Confocal Optical Coherence Tomography (LC-OCT), an optical imaging device, to non-invasively visualize microscopic changes to skin anatomy after hydradermabrasion treatment. MATERIALS/METHODS: Eight volunteers (Fitzpatrick skin types II-V) were recruited for this study. Images, using LC-OCT (DeepLive, DAMAE medical) were obtained before and after hydradermabrasion and at 2 weeks post-treatment. A commercially available hydradermabrasion device was utilized to perform the dermabrasion. RESULTS: In the epidermis, initially, a decrease in the average thickness of the stratum corneum, from 9.42 to 6.67 µm was visualized in LC-OCT images after hydradermabrasion. However, at 2 weeks of follow-up, the average stratum corneum thickness was 9.75 µm, resulting in an overall increase in the average thickness after treatment. Improved homogenization of the stratum corneum and decreased number of undulations in the epidermis post-treatment were also visualized. In all the subjects, the superficial dermis appeared stretched, which returned to baseline by the 2-week follow-up. At the 2-week follow-up, there were no visible differences in the quality and quantity of collagen fibers in the dermis. CONCLUSION: In our study, LC-OCT images of the epidermis and dermis demonstrated microscopic features of skin rejuvenation when treated with hydradermabrasion. Thus, not only highlighting the efficacy of hydradermabrasion but also the potential of LC-OCT to serve as a tool for visualizing the microscopic effects of cosmetic procedures on skin anatomy.

In vivo assessment of early effects of diamond-tipped microdermabrasion through the lens of line-field confocal optical coherence tomography.

BACKGROUND: Microdermabrasion is a cosmetic procedure that has gained popularity for skin rejuvenation by causing repetitive intraepidermal injury to stimulate the proliferation of fibroblasts and collagen production. Various clinical studies have demonstrated microdermabrasion's effectiveness in skin rejuvenation; however, most of these studies rely on clinical observation and scoring by observers rather than histologic or microscopic analysis. In our single-center prospective study, we used line-field confocal optical coherence tomography (LC-OCT), to non-invasively visualize the early effects of one microdermabrasion treatment on the facial epidermal and dermal structure. AIM: Using LC-OCT, this study aims to elucidate the microscopic and histological effects of microdermabrasion on epidermal and dermal structures, including epidermal thickness, as well as collagen and vascular patterns. PATIENTS/METHODS: Eight volunteers (Fitzpatrick skin types II-V) underwent one treatment of microdermabrasion. LC-OCT and VISIA imaging were performed before and 10 min after microdermabrasion, and at 48-h follow-up. Subjective evaluations of skin texture and adverse reactions were assessed 1 week posttreatment via a telephone call. RESULTS: Compared to LC-OCT images before treatment, images captured after one treatment of microdermabrasion showed a decrease in thickness and number of undulations in the stratum corneum. In the superficial dermis, enhancement in fibrillar collagen, as demonstrated by an increased prominence of crisscrossing hyper-refractile strands, was visualized. This was consistent with subjective and objective improvement in facial rhytids calculated by VISIA skin analysis. CONCLUSIONS: Treatment monitoring with LC-OCT demonstrated consistent histopathological changes with clinical visual improvement. Therefore, LC-OCT, has the potential to enable long-term histopathological monitoring of microdermabrasion and other cosmetic procedures without biopsy.

Ex vivo confocal microscopy features of common benign lesions that mimic non-melanoma skin cancers: Towards clinical integration.

Ex vivo confocal microscope (EVCM) rapidly images freshly excised tissue at a histopathological resolution. EVCM features of keratinocyte skin cancers are well-established, but those of benign clinical mimickers remain scarce. We describe EVCM features of common benign lesions and compare them with their malignant differentials. EVCM was used to image 14 benign and 3 cancer tissues. We compared EVCM features of benign lesions with corresponding histopathology and with those of keratinocyte cancers. Key features of benign lesions were identified and differentiated from malignant lesions. Elastin and fat appeared prominent in EVCM; while koilocytes and melanin were difficult to identify. Visualization of entire epidermis was challenging due to difficulty of tissue flattening during imaging. Benign lesions can be differentiated from keratinocyte cancers with EVCM. Using EVCM, a rapid, bedside diagnosis and management of skin neoplasms is possible, especially in a remote location without a histopathology lab.

Dual contrastive learning based image-to-image translation of unstained skin tissue into virtually stained H&E images.

Staining is a crucial step in histopathology that prepares tissue sections for microscopic examination. Hematoxylin and eosin (H&E) staining, also known as basic or routine staining, is used in 80% of histopathology slides worldwide. To enhance the histopathology workflow, recent research has focused on integrating generative artificial intelligence and deep learning models. These models have the potential to improve staining accuracy, reduce staining time, and minimize the use of hazardous chemicals, making histopathology a safer and more efficient field. In this study, we introduce a novel three-stage, dual contrastive learning-based, image-to-image generative (DCLGAN) model for virtually applying an "H&E stain" to unstained skin tissue images. The proposed model utilizes a unique learning setting comprising two pairs of generators and discriminators. By employing contrastive learning, our model maximizes the mutual information between traditional H&E-stained and virtually stained H&E patches. Our dataset consists of pairs of unstained and H&E-stained images, scanned with a brightfield microscope at 20 × magnification, providing a comprehensive set of training and testing images for evaluating the efficacy of our proposed model. Two metrics, Fréchet Inception Distance (FID) and Kernel Inception Distance (KID), were used to quantitatively evaluate virtual stained slides. Our analysis revealed that the average FID score between virtually stained and H&E-stained images (80.47) was considerably lower than that between unstained and virtually stained slides (342.01), and unstained and H&E stained (320.4) indicating a similarity virtual and H&E stains. Similarly, the mean KID score between H&E stained and virtually stained images (0.022) was significantly lower than the mean KID score between unstained and H&E stained (0.28) or unstained and virtually stained (0.31) images. In addition, a group of experienced dermatopathologists evaluated traditional and virtually stained images and demonstrated an average agreement of 78.8% and 90.2% for paired and single virtual stained image evaluations, respectively. Our study demonstrates that the proposed three-stage dual contrastive learning-based image-to-image generative model is effective in generating virtual stained images, as indicated by quantified parameters and grader evaluations. In addition, our findings suggest that GAN models have the potential to replace traditional H&E staining, which can reduce both time and environmental impact. This study highlights the promise of virtual staining as a viable alternative to traditional staining techniques in histopathology.

A case study on the dermatoscopic findings of Darier's disease in skin type VI.

We present dermatoscopic findings of long-standing, untreated Darier's disease (DD) in skin type VI that differs from current findings in literature. Robust hyperkeratotic polygonal-shaped plugs without a surrounding white halo and classic vascular features were noted on the anterior scalp, neck, axilla, midline trunk, and extensors. Through this case, we aim to contribute to emerging literature in describing features of DD under dermatoscopy to augment diagnosis.

Cutaneous adverse effects associated with LAG-3 inhibitor use in cancer treatment: A systematic review.

Immunotherapy has become a mainstay of treatment for many cancers. Multiple immune checkpoint inhibitors have been used to treat malignancies, including anti-programed death-1 (PD1) and anti-cytotoxic T-lymphocyte-associated protein (anti-CTLA4). However, a significant percentage of patients develop resistance to these immunotherapy drugs. Therefore, novel strategies were developed to target other aspects of the immune response. Lymphocyte activation gene-3 (LAG-3) is a cell-surface molecule found on natural killer cells and activated T-cells which negatively regulates T-cell proliferation and function. LAG-3 inhibitors interact with LAG-3 ligands on the surface of T-cells to block T-regulatory (Treg) cell activity, suppress cytokine secretion and restore dysfunctional effector T-cells which subsequently attack and destroy cancer cells. This review reports the dermatologic side effects associated with LAG-3 inhibitors used in the treatment of melanomas. Using PRISMA 2022 guidelines, a comprehensive literature review of PubMed, Google Scholar, Embase, Cochrane, and Web of Science databases was conducted. Three studies were identified that demonstrated that the use of LAG-3 inhibitors, whether as a single agent or in combination with other immune checkpoint inhibitors, resulted in stomatitis, pruritus, rash, dry skin, erythema, and vitiligo. Further research is warranted to assess the cutaneous adverse events observed with LAG-3 inhibitors in treating melanoma and to identify populations most vulnerable to such side effects.

The role of reflectance confocal microscopy in the diagnosis and management of pigmentary disorders: A review.

BACKGROUND: Reflectance confocal microscopy (RCM) has quickly transitioned from a research tool to an adjunct diagnostic bedside tool, providing the opportunity for noninvasive evaluation of skin lesions with histologic resolution. RCM is an optical imaging technique that uses near-infrared excitation wavelengths and safe low-power lasers. En-face images of different skin layers (up to the superficial dermis) are acquired in grayscale based on the reflective indices of tissue components. Melanin has the highest reflective index (contrast) and appears bright on RCM. AIMS: We present a review of the current literature on the use of RCM in the diagnosis and management of pigmentary disorders. METHODS: We reviewed PubMed and Ovid Medline databases from January 2000 to June 2021, using MeSH key terms: "reflectance confocal microscopy, confocal laser scanning microscopy, pigmentary disorders, treatment, melasma, vitiligo, freckles, solar lentigo, lentigo, tattoo, complications, melanoma, skin cancers, pigmented lesions, post inflammatory, melanin, photoaging" to identify studies and review articles discussing the use of RCM in the diagnosis and management of pigmentary disorders. RESULTS: RCM findings of pigmentary disorders were divided into the following categories: (1) disorders of increased pigmentation (post-inflammatory hyperpigmentation, melasma, Riehl's melanosis, solar lentigines, ephelides, hori nevus, naevus of Ota, café-au-lait macules, melanocytic nevus, melanoma, nevus spilus, labial mucosal melanosis, and mucosal melanoma), (2) disorders of decreased pigmentation or depigmentation (post-inflammatory hypopigmentation, vitiligo, nevus depigmentosus, halo nevus), and (3) exogenous pigmentation (tattoo, ochronosis). CONCLUSION: RCM has been explored and proven valuable for the evaluation and management of pigmentary disorders including melasma, vitiligo, solar lentigines, tattoo, and tattoo-related complications.

Imaging Tools for Noninvasive Hair Assessment.

Trichology tools historically have been limited in their ability to provide noninvasive detailed assessments of the hair and scalp. Recent advances in diagnostic and treatment monitoring technologies have begun to fill this gap. Global photography previously relied on a film camera and stereotactic imaging equipment but has been simplified by the advent of cameras that use software analysis and provide adjustable outlines to match facial features for the capture of standardized views. Reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) both enable in vivo visualization of subcutaneous structures and provide new insight into the dynamic subclinical changes of alopecia. Recent efforts focus on training convolutional neural networks to quantify various hair parameters on OCT scans. When scalp biopsy is necessary, trichoscopy, RCM, and OCT can guide in selecting biopsy sites. Because of the growing clinical applications of these technologies, clinicians should be aware of the advantages and limitations of noninvasive hair-imaging tools.

Metastatic renal cell carcinoma presenting as multiple cutaneous lesions visualized through reflectance confocal microscopy.

We present the first case of metastatic renal cell carcinoma visualized via reflectance confocal microscopy (RCM). This case describes the RCM features of such a tumor, in an effort to improve noninvasive characterization of cutaneous metastases.

Double vision due to lateral rectus injury after cosmetic botulinum toxin injections.

Facial intramuscular injections of Botulinum toxin (BoNT) injections are among the most common cosmetic procedures in dermatology. Rarely, serious adverse reactions such as blepharoptosis, diplopia and periorbital hematoma may occur with improper administration technique. Here we report a case of painless diplopia 5 weeks post-BoNT injection for 'crow's feet' likely due to inadvertent BoNT diffusion into the lateral rectus muscle causing a temporary palsy. This case aims to raise awareness of proper cosmetic BoNT injection techniques in the periorbital area to avoid ophthalmic complications.

Role of VivaScope 2500 ex vivo confocal microscopy in skin pathology: Advantages, limitations, and future prospects.

BACKGROUND: Vivascope 2500 ex vivo confocal microscopy (EVCM) is an emerging optical imaging device that allows nuclear level resolution of freshly excised tissues. EVCM provides, rapid real-time pathological examination in many subspecialties of pathology including skin, prostate, breast, liver, etc. In contrast to traditional time-consuming frozen sectioning and histological analysis. AIMS: To evaluate the current state of EVCM utilization. MATERIALS AND METHODS: This study highlights the advantages, limitations, and prospects of EVCM in skin pathology. RESULTS: Our findings demonstrate that EVCM is a promising adjunctive tool to assess margins in Mohs surgery and to provide rapid, accurate diagnosis of cutaneous tumors, infectious and inflammatory diseases. CONCLUSION: EVCM is a revolutionary device that can be used as an adjunct to paraffin-fixed, hematoxylin and eosin-stained slides and frozen sectioning. Additional refinements are required before EVCM can be used as an alternative to frozen sectioning or traditional tissue processing.

Demystifying the mechanism of action of professional facial peeling: In-vivo visualization and quantification of changes in inflammation, melanin and collagen using Vivascope® and ConfoScan®.

Professional peeling using chemicals (chemical peeling) is a popular non-surgical procedure commonly used for the treatment for photoaging, pigmentary disorders, scarring, fine lines, and wrinkles. The objective of our case study was to elucidate the mechanism of action of professional peels/peeling. For proof-of-concept, we used a commercial blended peel containing trichloroacetic acid and lactic acid. The facial peeling was performed by a physician on four subjects. These subjects were followed over time in the clinic to take clinical pictures and monitor surface and anatomical changes in inflammation, melanin, and collagen at regular intervals post-peel (5 min, 48 h, and day 9). Dermoscope and Vivascope® were used to image surface and subsurface anatomical changes, respectively, and ConfoScan® was used to quantify aforementioned anatomical changes. Based on Vivascope and ConfoScan analysis, we could see clear visual clinical evidence of controlled injury-healing mechanism of peel's action: immediate but transient onset of inflammation within 5 min (indicate injury response by skin), followed by melanin redistribution evident at 48 h (indicate activation of skin's defense system), and remodeled fibrous collagen network without any inflammatory cells on day 9 (healing response). To our knowledge, this is the first ever clinical study to deconvolute the mysterious mechanism of action of peels, in-vivo.

Applications of Reflectance Confocal Microscopy in the Diagnosis of Fungal Infections: A Systematic Review.

Cutaneous and adnexal fungal infections are typically diagnosed with potassium hydroxide (KOH) skin scrapings, fungal cultures, and Periodic acid-Schiff (PAS) biopsy staining. All three current methods of fungal diagnosis require sample processing and turnover time which leads to a delay in diagnosis. Reflectance confocal microscopy (RCM) is a non-invasive, in vivo skin imaging technology that provides real-time dermatologic diagnoses. We present an updated systematic review of the applications of RCM in diagnosing fungal infections in an effort to explore the utility of RCM as an adjunct clinical tool in detecting cutaneous and adnexal fungi We systematically searched the MEDLINE (via PubMed) for studies published from January 2000 to October 2022 that described the utility of RCM in the setting of fungal infections. Of the 25 studies that met the inclusion criteria, 202 patients were included. The following information on the application of RCM in the setting of fungal infections was extracted from each study, if reported: study type, year published, number of patients included, diagnosis/diagnostic methods, and RCM description. Concordant within all included studies, fungal infections presented on RCM as bright, linear, branching, filamentous structures at the level of stratum corneum. A limitation of this review is that 11 of 25 studies were case reports (n = 1). Larger scale studies should be conducted to explore the utility of RCM in diagnosing fungal infections and to enrich the RCM descriptions of specific fungal conditions.