Thin Amelanotic and Hypomelanotic Melanoma: Clinicopathological and Dermoscopic Features.

Background and Objectives: Amelanotic/hypomelanotic melanomas (AHMs) account for 2-8% of all cutaneous melanomas. Due to their clinical appearance and the lack of specific dermoscopic indicators, AHMs are challenging to diagnose, particularly in thinner cutaneous lesions. The aim of our study was to evaluate the clinicopathological and dermoscopic features of thin AHMs. Identifying the baseline clinical-pathological features and dermoscopic aspects of thin AHMs is crucial to better understand this entity. Materials and Methods: We divided the AHM cohort into two groups based on Breslow thickness: thin (≤1.00 mm) and thick (>1.00 mm). This stratification helped identify any significant clinicopathological differences between the groups. For dermoscopic analysis, we employed the "pattern analysis" approach, which involves a simultaneous and subjective assessment of different criteria. Results: Out of the 2.800 melanomas analyzed for Breslow thickness, 153 were identified as AHMs. Among these, 65 patients presented with thin AHMs and 88 with thick AHMs. Red hair color and phototype II were more prevalent in patients with thin AHMs. The trunk was the most common anatomic site for thin AHMs. Patients with thin AHMs showed a higher number of multiple melanomas. Dermoscopic analysis revealed no significant difference between thin AHMs and thick AHMs, except for a more frequent occurrence of residual reticulum in thin AHMs. Conclusions: Thin AHMs typically affect individuals with lower phototypes and red hair color. These aspects can be related to the higher presence of pheomelanin, which provides limited protection against sun damage. This also correlates with the fact that the trunk, a site commonly exposed to intermittent sun exposure, is the primary anatomical location for thin AHMs. Multiple primary melanomas are more common in patients with thin AHMs, likely due to an intrinsic predisposition as well as greater periodic dermatologic follow-ups in this class of patients. Apart from the presence of residual reticulum, no other significant dermoscopic differences were observed, complicating the differential diagnosis between thin and thick AHMs based on dermoscopy alone.

Role of reflectance confocal microscopy for in vivo investigation of oral disorders: White, red and pigmented lesions.

In vivo reflectance confocal microscopy (RCM) is poorly investigated in oral pathology due to the peculiar anatomical and topographical oral mucosa features. A dedicated handheld confocal microscope with an intra-oral probe was developed for oral mucosa imaging. The main objective was to describe the healthy oral mucosa and the cytoarchitectural findings detectable in different oral disorders by means of the newly designed handheld confocal microscope. Secondary aim was to identify the main RCM criteria that differentiate oral lesions in order to provide algorithm for a rapid non-invasive evaluation. This observational retrospective study included all consecutive patients with oral disorders and volunteers with healthy oral mucosa who underwent RCM examination in our outpatient clinic from September 2018 to December 2021. Three different investigators examined together the RCM images to detect the key features and secondary criteria for each type of oral lesion collected. The study population included 110 patients affected by oral lesions and seven volunteers with healthy oral mucosae. A total of 15 oral disorders were imaged and divided in three main groups: white, red and pigmented lesions. Key features and secondary criteria were identified for every single type of oral disease. RCM permits a cytoarchitectural evaluation of the oral mucosae affected by inflammatory, dysplastic and neoplastic diseases, thus orienting the clinicians towards non-invasive diagnosis and enhancing the diagnostic management. The "tree diagrams" proposed allow a schematic and simplified view of confocal features for each type of oral disease, thus drastically reducing the diagnostic timing.

Topical chlormethine gel in the treatment of mycosis fungoides: A single-center real-life experience and systematic review of the literature.

Gel formulation of chlormethine (CG) has gained a preeminent role among therapies available for mycosis fungoides (MF). To evaluate the frequency of use of CG for MF treatment and to determine the limits and potentialities of CG in a real-world setting. A systematic review of articles published prior to October 2021 was performed. Articles were included in the review if a full-text English version was available. MEDLINE (PubMed), Scopus, and Web of Science were each queried from their date of inception with the following terms: "mechlorethamine gel", "chlormethine gel", and "mycosis fungoides". The reference lists of the studies retrieved were searched manually. Moreover, this study included all consecutive patients with different stages of MF (from IA to IIB) who started treatment with CG gel between July 2020 and May 2021. Data of the literature were compared to our single-center real-life experience. Of the surveyed literature, 11 publications were included in the final analysis describing a total of 548 patients with MF. Eleven patients with a median (standard deviation) age of 66 years (15.1) were enrolled and followed up, receiving CG (0.02% chlormethine HCl). Response to treatment resulted higher (90.1%) in our study population than in other real-world experiences published in literature. This systematic review supports the role of CG for MF treatment, showing its limits and potentialities. Our single-center real-life experience revealed an elevated percentage of clinical response with high safety and tolerance, demonstrating its versatile use with dose and application rate adaptability.

Hidradenitis Suppurativa in a Large Cohort of Italian Patients: Evaluation of the Burden of Disease.

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, inflammatory, recurrent, debilitating skin disease of the hair follicle that usually occurs after puberty with painful, deep-seated, inflamed nodules and sinus tracts in the apocrine gland-bearing areas of the body, most commonly the axillae and inguinal and anogenital regions, with a relevant impact on patients' quality of life (QoL). OBJECTIVE: To evaluate how the burden of HS disease impacts on patient well-being and working activities in a large Italian population over a period of 9 months. METHODS: A multicenter, prospective, epidemiologic cohort study was conducted in adult Italian patients with HS. HS severity was assessed through Hurley stage and HS Physician's Global Assessment (HS-PGA), clinical improvement by HS Clinical Response (HiSCR) and partial response, and disease burden through QoL questionnaires (HIDRAdisk, Skindex-16, Dermatology Life Quality Index [DLQI]), and Work Productivity and Activity Impairment - General Health (WPAI:GH). RESULTS: A total of 308 patients (56.2% women; mean age 35.2 ± 12.9 years) were enrolled in 27 dermatologic clinics. Men were older (37.4 years vs. 33.5), more smoking addicted (74.1% vs. 60.1%), and alcohol consumer (34.1% vs. 13.9%), while more women were obese (34.10% vs. 22.22%). At baseline, most patients had a Hurley severity stage of 2 (43.9%), a moderate HS-PGA score (57.1%), and poor QoL (HIDRAdisk: 65.7 ± 23.3, Skindex-16: 60.3 ± 26.9, and DLQI: 10.8 ± 8.1). Patients with more severe disease showed worse QoL. Mean values for the variables related to HS severity decreased during the study period. The achievement of HiSCR and partial response increased during the study. CONCLUSION: This study offers insight into the disease burden of HS in an Italian population. Our results underline the impact of QoL evaluation, also with the use of the HIDRAdisk, in clinical routine as a support to validated severity clinical and instrumental indexes for a "360-degree" assessment of HS patient's burden of disease.

Assessing changes in facial skin quality using noninvasive in vivo clinical skin imaging techniques after use of a topical retinoid product in subjects with moderate-to-severe photodamage.

BACKGROUND: Studies utilizing reflectance confocal microscopy (RCM) and dynamic optical coherence tomography (D-OCT) to assess cosmetic skin changes are limited. METHODS: A 12-week, open-label study was conducted using RCM and D-OCT to evaluate the effects of a topical cosmetic retinol (RET05) on subjects with facial photodamage. Study endpoints included investigator grading, standardized (VISIA-CR) and 3D photography (Antera 3D), independent RCM (VivaScope1500) and D-OCT (VivoSight) image analysis, validated FACE-Q scales, and subject questionnaires. RESULTS: Twenty-three subjects, 45- to 68-year old, with Fitzpatrick skin types II-IV completed the study. After 12 weeks of repeated application, RET05 demonstrated significant corresponding cosmetic improvements for overall photodamage, skin tone unevenness, tactile roughness, fine lines/wrinkles (forehead, periocular, and perioral), and coarse lines/wrinkles (forehead, periocular, and cheeks), and Allergan Skin Roughness Scale. FACE-Q assessments also demonstrated significant improvements from baseline at week 12. RCM analysis showed decreases in all epidermis, less compact stratum corneum (SC), more non-compact SC, decreases in coarse/huddled dermal fibers, and increases in fibrillar dermal fibers, as compared to baseline. D-OCT analysis showed significant decreases in epidermal thickness (ET), reduction of moderate/many collagen fragments and collagen bundles, and significant increases in the stroma attenuation coefficient and collagen density. Moreover, the dermal-epidermal junction was more pronounced, and vascular abundance at 300 and 500 µm depth increased. Independent evaluation of RCM and D-OCT images showed similar decreases in ET and improvements in dermal fibers. CONCLUSION: This study was the first to utilize RCM and D-OCT to evaluate the cosmetic effects of a topical retinoid and further substantiate improvements in skin quality.

Dermoscopy, confocal microscopy and optical coherence tomography features of main inflammatory and autoimmune skin diseases: A systematic review.

BACKGROUND/OBJECTIVES: Non-invasive skin imaging features of main skin inflammatory and autoimmune diseases have been reported, although a comprehensive review of their correlation with histopathologic features is currently lacking. Therefore, the aim of this paper was to review the correlation of dermoscopic, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) criteria of main inflammatory and autoimmune skin diseases with their corresponding histopathologic criteria correlation. METHODS: Studies on human subjects affected by main inflammatory and autoimmune diseases, defining the correlation of dermoscopic, RCM or OCT with histopathologic criteria, were included in the review. Five groups of diseases were identified and described: psoriasiform, spongiotic and interface dermatitis, bullous diseases and scleroderma. RESULTS: Psoriasiform dermatitis was typified by white scales, corresponding to hyperkeratosis, and vessels, observed with RCM and OCT. Spongiosis, corresponding to dark areas within the epidermis with RCM and OCT, was the main feature of spongiotic dermatitis. Interface dermatitis was characterised by dermoepidermal junction obscuration. Blisters, typical of bullous diseases, were visualised as dark areas with RCM and OCT while scleroderma lesions were characterised by dermoscopic fibrotic beams, related to dermal thickness variations, with specific OCT and histopathologic correlations. CONCLUSIONS: Although the role of RCM and OCT has yet to be defined in clinical practice, non-invasive skin imaging shows promising results on inflammatory and autoimmune skin diseases, due to the correlation with histopathologic features.

Skin tags imaged by reflectance confocal microscopy, optical coherence tomography and multispectral optoacoustic tomography at the bedside.

BACKGROUND: Skin tags are common and mostly benign, but occasionally contain skin cancers. This study analysed skin tags by combining three advanced optical imaging technologies: reflectance confocal microscopy (RCM), optical coherence tomography (OCT) and multispectral optoacoustic imaging (MSOT) supplemented by dermoscopy MATERIALS AND METHODS: A prospective clinical study recruiting patients with skin tags from a university hospital clinic over a 2-week period. OCT, RCM and MSOT imaging were performed prior to excisional biopsies. Image features such as pigmentation, cell types and skin architecture, angiographic information demonstrating vascular pattern were captured, analysed, and compared to melanin and haemoglobin content in MSOT as well as histopathology. RESULTS: Six patients with dermal naevi (2); compound naevi (3); neurofibroma (1) were included. All skin tags except the neurofibroma were pigmented (5/6), with sparse (5/6) and dense (4/6) hyperreflective nests and band-like collagen in dermis in 6/6 lesions on RCM. Dermoscopy showed dots (5/6) and coiled vessels (5/6). Linear vertical vessels were present in all OCT images. MSOT images consisted of a compact shell-like superficial melanin area, same shape and size as the skin tag, dermal vessels were visible in 4/5 naevi, HbO2 signal clearly demarcated blood vessels located below the melanin signal. CONCLUSION: OCT showed linear vessels in all lesions. Pigmentation was identified by RCM as benign nests of melanocytes. MSOT supplemented with spatial distribution of melanin and HbO2 that indicated all skin tags were benign with no infiltration of vessels inside the melanin signal. Each advanced method proved indispensable for fast diagnosis. Larger studies are warranted for validation.

Reflectance Confocal Microscopy, Optical Coherence Tomography, and Multiphoton Microscopy in Inflammatory Skin Disease Diagnosis.

BACKGROUND AND OBJECTIVES: Technological advances in medicine have brought about many novel skin imaging devices. This review aims to evaluate the scientific evidence supporting the use of noninvasive optical imaging techniques to aid in the diagnosis and prognosis of inflammatory skin diseases. STUDY DESIGN/MATERIALS AND METHODS: PubMed and Scopus were searched in September 2020 according to PRISMA guidelines for articles using reflectance confocal microscopy (RCM), optical coherence tomography (OCT), and multiphoton microscopy (MPM) in inflammatory skin diseases, excluding studies monitoring treatment efficacy. RESULTS: At the time of the study, there were 66 articles that addressed the utilization of noninvasive imaging in interface, spongiotic, psoriasiform, vesiculobullous, and fibrosing/sclerosing inflammatory skin dermatoses: RCM was utilized in 46, OCT in 16, and MPM in 5 articles. RCM was most investigated in psoriasiform dermatoses, whereas OCT and MPM were both most investigated in spongiotic dermatoses, including atopic dermatitis and allergic contact dermatitis. CONCLUSIONS: There is preliminary evidence to support the diagnostic potential of noninvasive optical imaging techniques in inflammatory skin diseases. Improvements in the devices and further correlation with histology will help broaden their utility. Additional studies are needed to determine the parameters for diagnostic features, disease differentiation, and staging of inflammatory skin conditions. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.

Towards data-driven quantification of skin ageing using reflectance confocal microscopy.

INTRODUCTION: Evaluation of skin ageing is a non-standardized, subjective process, with typical measures relying coarse, qualitatively defined features. Reflectance confocal microscopy depth stacks contain indicators of both chrono-ageing and photo-ageing. We hypothesize that an ageing scale could be constructed using machine learning and image analysis, creating a data-driven quantification of skin ageing without human assessment. METHODS: En-face sections of reflectance confocal microscopy depth stacks from the dorsal and volar forearm of 74 participants (36/18/20 training/testing/validation) were represented using a histogram of visual features learned using unsupervised clustering of small image patches. A logistic regression classifier was trained on these histograms to differentiate between stacks from 20- to 30-year-old and 50- to 70-year-old volunteers. The probabilistic output of the logistic regression was used as the fine-grained ageing score for that stack in the testing set ranging from 0 to 1. Evaluation was performed in two ways: on the test set, the AUC was collected for the binary classification problem as well as by statistical comparison of the scores for age and body site groups. Final validation was performed by assessing the accuracy of the ageing score measurement on 20 depth stacks not used for training or evaluating the classifier. RESULTS: The classifier effectively differentiated stacks from age groups with a test set AUC of 0.908. Mean scores were significantly different when comparing age groups (mean 0.70 vs. 0.44; t = -6.62, p = 0.0000) and also when comparing stacks from dorsal and volar body sites (mean 0.64 vs. 0.53; t = 3.12, p = 0.0062). On the final validation set, 17 out of 20 depth stacks were correctly labelled. DISCUSSION: Despite being limited to only coarse training information in the form of example stacks from two age groups, the trained classifier was still able to effectively discriminate between younger skin and older skin. Curiously, despite being only trained with chronological age, there was still evidence for measurable differences in age scores due to sun exposure-with marked differences in scores on sun-exposed dorsal sites of some volunteers compared with less sun-exposed volar sites. These results suggest that fine-grained data-driven quantification of skin ageing is achievable.

INTRODUCTION: L'évaluation du vieillissement de la peau est un processus subjectif et non standardisé, dont les mesures typiques reposent sur des caractéristiques grossières et définies qualitativement. Les strates de profondeur observées grâce à la microscopie confocale par réflectance contiennent des indicateurs de chrono-vieillissement et de photo-vieillissement. Nous émettons l'hypothèse selon laquelle il serait possible d'établir une échelle de vieillissement à l'aide de l'apprentissage automatique et de l'analyse d'images, permettant la mise en place d'une quantification du vieillissement cutané fondée sur les données et sans évaluation humaine. MÉTHODES: À l'aide d'un histogramme des caractéristiques visuelles apprises à partir de petits ensembles d'images regroupées sans supervision, on a représenté des coupes faciales de strates de profondeur observées grâce à la microscopie confocale par réflectance et issues des faces dorsale et palmaire de l'avant-bras de 74 participants (36/18/20 entraînement/analyse/validation). Après un processus d'entraînement portant sur ces histogrammes, un classificateur de régression logistique a appris à différencier les strates prélevées sur des volontaires âgés de 20 à 30 ans et celles prélevées sur des volontaires âgés de 50 à 70 ans. Le résultat probabiliste de la régression logistique a été utilisé comme score du vieillissement de haute précision, allant de 0 à 1, pour cette strate dans l'ensemble d'analyse. L'évaluation a été effectuée de deux manières : dans l'ensemble d'analyse, l'aire sous la courbe (ASC) a été identifiée pour le problème de classification binaire ainsi que par comparaison statistique des scores selon les tranches d'âge et les catégories de site corporel. La validation finale est passée par une évaluation de l'exactitude de la mesure du score de vieillissement sur 20 strates de profondeur non utilisées dans le cadre du processus d'entraînement ou d'évaluation du classificateur. RÉSULTATS: Le classificateur différenciait efficacement les strates des tranches d'âge, avec une ASC dans l'ensemble d'analyse de 0,908. Les scores moyens affichaient des différences significatives lors de la comparaison entre les tranches d'âge (moyenne de 0,70 contre 0,44 ; t = 6,62 ; p = 0,0000) et lors de la comparaison entre les strates issues des faces dorsale et palmaire des sites corporels (moyenne de 0,64 contre 0,53 ; t = 3,12 ; p = 0,0062). Dans l'ensemble de validation finale, 17 strates sur 20 ont été correctement classées.

Dermoscopy and confocal microscopy for different chemotherapy-induced alopecia (CIA) phases characterization: Preliminary study.

BACKGROUND: Chemotherapy-induced alopecia (CIA) affects 65% of patients receiving chemotherapy regimens and is often identified with the massive hair loss stage. Reflectance confocal microscopy (RCM) is a noninvasive technique used in alopecia assessment for disease characterization and state of activity. OBJECTIVE: To describe RCM features of CIA in different timing and identify specific phases of alopecia development. METHODS: A total of 16 patients treated with chemotherapy underwent dermoscopy and RCM evaluations four times during the observation: 2 and 4-6 weeks after starting and 3 and 6 months after the end of chemotherapy. Ten examinations for each stage were performed. RESULTS: Four phases of CIA have been identified. Initial hair loss showed specific dots not previously described, named CIA dots. massive hair loss phase was characterized by black dots (10/10 pt), CIA dots (8/10 pt) and hair shaft abnormalities. Three months after the end of chemotherapy, during the partial regrowth phase, 10/10 patients showed thin hair in regrowth and 8/10 presented black and yellow dots. At 6 months, normal hair in regrowth appears in all patients (total regrowth phase). CONCLUSIONS: Chemotherapy-induced alopecia has to be considered as a dynamic process with specific phases characterized by distinctive dermoscopic and confocal features.

Clinical management of very small pigmented lesions: Improved clinical outcome through dermoscopy and reflectance confocal microscopy combination.

INTRODUCTION: Small-sized pigmented lesions (SSPL) <3 mm in diameter are common pitfall in the daily dermatology practice. Dermoscopy alone is hampered by the lack of specific features inversely proportional to the diameter of the lesions and its performance is highly operator-dependent. Reflectance confocal microscopy (RCM) has been demonstrated to be effective in the diagnosis of several difficult lesions where dermoscopy lacks to provide conclusive information. MATERIALS AND METHODS: A total of 179 lesions with uncertain or equivocal clinical and dermoscopy appearance were selected. Dermoscopist has been requested to express a diagnostic suspect when possible. Equivocal lesions underwent RCM performed by expert for second-level evaluation before surgical excision for histological diagnosis. Results have been later statistically analysed. RESULTS: Dermoscopy was not diagnostic in large number of lesions with low concordance histology (39.1%) instead of a much high concordance when combined with RCM (93.9%). CONCLUSIONS: Small-sized pigmented lesions were more likely to be located on the face area. Diagnosis of pigmented BCC was relatively easy on dermoscopy and also in the case of small lesions showing typical signs of BCC. LM and MM have been seen to be particularly difficult to be diagnosed using only dermoscopy. The combination of digital dermoscopy and RCM represents the correct approach of SSPL.

Concordance among in vivo reflectance confocal microscopy, trichoscopy, and histopathology in the evaluation of scalp discoid lupus.

BACKGROUND: Reflectance confocal microscopy (RCM) has been used for the evaluation of several inflammatory skin conditions, including skin discoid lupus erythematosus (DLE), and has been correlated with conventional histopathology (HP). However, RCM is not being widely used in trichology. Few reports and just preliminary data suggest the use of RCM as a complementary tool in alopecias. OBJECTIVES: To correlate the major RCM features of scalp DLE with trichoscopy and HP findings of biopsy specimens obtained from the same lesions. METHODS: This is an observational, analytical, and cross-sectional study involving 12 patients with a clinically established diagnosis of scalp DLE. Patients underwent global clinical photograph, trichoscopy, and RCM examination in the same site followed by two 4-mm punch biopsy specimens for HP analysis. Inter-methods agreement among RCM imaging, trichoscopy, and horizontal histopathology sections (HHS) were calculated using Cohen Kappa (k) statistics. RESULTS: Statistical analysis of the agreement between RCM and HP features disclosed an overall agreement similar to skin DLE. Seven of the eleven features evaluated had agreement superior to 75%. We also evaluated RCM features associated with three of their corresponding trichoscopic findings for further investigation of their agreement with HP. Statistical analysis showed an enhancement with agreement of 86% when the non-invasive techniques are used together. CONCLUSION: Consistent correlation between RCM and HP observed in our study supports the reliability of RCM in the diagnosis of scalp DLE. RCM may be considered a promising tool for scalp DLE microscopic evaluation and presents similar RCM features to DLE in other body sites. By associating clinical, trichoscopic and RCM evaluation, dermatologists will have a non-invasive arsenal for the assessment of hair and scalp disorders, benefiting patients.

In Vivo Reflectance Confocal Microscopy of Gold Microparticles Deposited in the Skin. A Case Report on Cutaneous Chrysiasis.

Cutaneous chrysiasis is gold deposition in the dermis, described after parenteral administration of gold salts or after topical exposure to gold-containing materials. Gold microparticles (GMPs) have versatile therapeutic effects and are increasingly used in medicine. This case report describes the development of a blue-gray macule following the facial application of GMPs and laser treatment of acne vulgaris. Dermoscopy showed a nonspecific homogenous blue-gray pattern, gradually fading over an 8-month-period. Reflectance confocal microscopy (RCM) detected hyperreflective, subcellular particles in the papillary dermis, localized around hair follicles, eccrine glands, and inside macrophages. Histopathological evaluation, darkfield illumination with hyperspectral imaging, and neutron activation analysis confirmed the presence of GMPs in the dermis. RCM allowed non-invasive fast visualization of aggregates of hyperreflective particles in the dermis and can potentially be used for monitoring localized cutaneous chrysiasis and other metal deposition conditions over time. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Reflectance confocal microscopy as a new diagnostic tool in transformed mycosis fungoides.

Patients with mycosis fungoides typically experience an indolent disease. In some cases, the disease undergoes a process of large cell transformation which often heralds a more aggressive course with shortened overall survival. In order to rule out large cell transformation, biopsy specimens are often collected from patients with established disease who develop new papules, plaques or tumours. In some cases, multiple biopsies are needed and scar, infection and sampling error can occur. Our aim was to evaluate lesions suggestive of large cell transformation using in vivo reflectance confocal microscopy and to correlate confocal features with histopathologic findings in three patients with biopsy-proven mycosis fungoides who developed new lesions during follow-up. A total of six lesions, two lesions per patient, were examined. Reflectance confocal microscopy demonstrated large bright roundish pleomorphic cells in the epidermis, dermoepidermal junction, dermis and hair follicle in 5 of 6 lesions. The same 5 lesions were confirmed as large cell transformation by histopathology. Dermoepidermal junction obscuration, Pautrier microabscesses, epidermal disarray, spongiosis and dendritic cells were also detected by reflectance confocal microscopy and correlated to histopathology. In conclusion, reflectance confocal microscopy is useful in identifying large cell transformation within mycosis fungoides lesions. Reflectance confocal microscopy can therefore be of value in targeting the biopsy site, thereby reducing the chance of a false-negative histopathological finding.

Feasibility of a Video-Mosaicking Approach to Extend the Field-of-View For Reflectance Confocal Microscopy in the Oral Cavity In Vivo.

BACKGROUND: Reflectance confocal microscopy (RCM) is a developing approach for noninvasive detection of oral lesions with label-free contrast and cellular-level resolution. For access into the oral cavity, confocal microscopes are being configured with small-diameter telescopic probes and small objective lenses. However, a small probe and objective lens allows for a rather small field-of-view relative to the large areas of tissue that must be examined for diagnosis. To extend the field-of-view for intraoral RCM imaging, we are investigating a video-mosaicking approach. METHODS: A relay telescope and objective lens were adapted to an existing confocal microscope for access into the oral cavity. Imaging was performed using metal three-dimensional-printed objective lens front-end caps with coverslip windows to contact and stabilize the tissue and set depth. Four healthy volunteers (normal oral mucosa), one patient (with an amalgam tattoo) in a clinical setting, and 20 anesthetized patients (with oral squamous cell carcinoma [OSCC]) in a surgical setting were imaged. Instead of the usual still RCM images, videos were recorded and then processed into video-mosaics. Thirty video-mosaics were read and qualitatively assessed by an expert reader of RCM images of the oral mucosa. RESULTS: Whereas the objective lens' native field-of-view is 0.75 mm × 0.75 mm, the video-mosaics display larger areas, ranging from 2 mm × 2 mm to 4 mm × 2 mm, with resolution, morphologic detail, and image quality that is preserved relative to that observed in the original videos (individual images). Video-mosaics in healthy volunteers' and the patients' images showed cellular morphologic patterns in the lower epithelium and at the epithelial junction, and connective tissue along with capillary loops and blood flow in the deeper lamina propria. In OSCC, tumor nests could be observed along with normal looking mucosa in margin areas. CONCLUSIONS: Video-mosaicking is a reasonably quick and efficient approach for extending the field-of-view of RCM imaging, which can, to some extent, overcome the inherent limitation of an intraoral probe's small field-of-view. Reading video-mosaics can mimic the procedure for examining pathology: initial visualization of the spatial cellular and morphologic patterns of the tumor and the spread of tumor margins over larger areas of the lesion, followed by digitally zooming (magnifying) for closer inspection of suspicious areas. However, faster processing of videos into video-mosaics will be necessary, to allow examination of video-mosaics in real-time at the bedside. Lasers Surg. Med. 51:439-451, 2019. © 2019 Wiley Periodicals, Inc.

Acne vulgaris severity graded by in vivo reflectance confocal microscopy and optical coherence tomography.

INTRODUCTION: Acne is an inflammatory disease of the pilosebaceous unit, which can be investigated in vivo using reflectance confocal microscopy (RCM) and optical coherence tomography (OCT). OBJECTIVES: By means of RCM and OCT to identify morphological characteristics of acne that may be associated with clinical acne severity. METHODS: Patients with mild to moderate facial acne (n = 14, Investigators Global Assessment scale, IGA 1-3), and healthy participants (n = 7, IGA 0) were included in this explorative study. A total of 108 RCM image blocks and 54 OCT scans (each RCM and OCT image measuring 6 × 6 mm) were captured from lesional-, perilesional, and lesion-free skin areas. Acne lesions, infundibular regions of follicles and inflammation degree were compared in acne patients and healthy participants. RESULTS: Combined use of RCM and OCT demonstrated infundibular morphology, acne lesions, and blood flow. RCM images of perilesional- and lesion-free skin in acne patients revealed follicle infundibula with hyperkeratinized borders and abundant keratin plugs, contrasting skin of healthy participants. Higher acne severity related to increased number of follicles with hyperkeratotic borders (P = 0.04) and keratin plugs (P = 0.006), increased infundibulum diameter (P < 0.001), increased density of inflammatory cells (P < 0.001), and blood flow (P = 0.03). Acne lesion morphology was not associated with acne severity. CONCLUSION: Combined use of RCM and OCT elucidated distinctive follicle infundibulum characteristics and inflammation degree that were associated with acne severity. Future trials may apply imaging techniques to support clinical acne grading, and monitor treatment efficacy. Lasers Surg. Med. 51:104-113, 2019. © 2018 Wiley Periodicals, Inc.

Handheld reflectance confocal microscopy for the diagnosis of molluscum contagiosum: Histopathology and dermoscopy correlation.

Handheld reflectance confocal microscopy may represent an adjunctive, fast, non-invasive tool for the diagnosis of molluscum contagiosum, revealing microscopic details closely related to histopathology, as demonstrated by this study evaluating 19 molluscum lesions in 11 patients. It permits the rapid examination of one or multiple skin lesions in real time and it is perfectly suitable for children.

In vivo reflectance confocal microscopy assessment of the therapeutic follow-up of cutaneous T-cell lymphomas causing scalp alopecia.

Cutaneous T-cell lymphomas involving the scalp and determining scarring alopecias are difficult to be followed up during treatment because of the peculiar anatomical site of onset. In vivo reflectance confocal microscopy has already been reported to be useful for cutaneous T-cell lymphoma evaluation and for therapeutic follow-up in inflammatory skin conditions. We describe a case of a 26-year-old man affected by cutaneous T-cell lymphoma affecting the scalp in which reflectance confocal microscopy demonstrated to be useful for in vivo evaluation of the therapeutic response to topical and systemic treatment.

Reflectance confocal microscopy features of seborrheic dermatitis for plaque psoriasis differentiation.

BACKGROUND: Plaque psoriasis (PP) and seborrheic dermatitis (SD) are chronic inflammatory skin diseases with similar clinical and pathological features. Differential diagnosis can be difficult, especially when particular skin areas of the face are involved. Reflectance confocal microscopy (RCM) has been demonstrated to be useful for 'real-time' diagnosis of skin inflammatory diseases. OBJECTIVE: To define distinctive confocal criteria of SD and to evaluate the usefulness of this technique for noninvasive differential diagnosis with PP. METHODS: A total of 40 patients affected by PP and 19 patients by SD involving the face were recruited and subjected to RCM evaluation. Univariate and adjusted odds ratios were calculated. Discriminant functions were used to plot ROC curves. RESULTS: The results disclosed specific patterns for SD and PP. The following distinctive confocal features for SD have been identified: spongiosis, dermal inflammation and horizontal orientation of dilated blood vessels. CONCLUSION: SD has a specific and easily recognizable confocal pattern supporting clinical differentiation with PP.