Microscopic and functional changes observed with dynamic optical coherence tomography for severe refractory atopic dermatitis treated with dupilumab

Eosinophils and tissue remodeling: Relevance to airway disease

The ability of human tissue to reorganize and restore its existing structure underlies tissue homeostasis in the healthy airways, but in disease can persist without normal resolution, leading to an altered airway structure. Eosinophils play a cardinal role in airway remodeling both in health and disease, driving epithelial homeostasis and extracellular matrix turnover. Physiological consequences associated with eosinophil-driven remodeling include impaired lung function and reduced bronchodilator reversibility in asthma, and obstructed airflow in chronic rhinosinusitis with nasal polyps. Given the contribution of airway remodeling to the development and persistence of symptoms in airways disease, targeting remodeling is an important therapeutic consideration. Indeed, there is early evidence that eosinophil attenuation may reduce remodeling and disease progression in asthma. This review provides an overview of tissue remodeling in both health and airway disease with a particular focus on eosinophilic asthma and chronic rhinosinusitis with nasal polyps, as well as the role of eosinophils in these processes and the implications for therapeutic interventions. Areas for future research are also noted, to help improve our understanding of the homeostatic and pathological roles of eosinophils in tissue remodeling, which should aid the development of targeted and effective treatments for eosinophilic diseases of the airways.

Multimodal OCT Control for Early Histological Signs of Vulvar Lichen Sclerosus Recurrence after Systemic PDT: Pilot Study

Photodynamic therapy (PDT) is a modern treatment for severe or treatment-resistant vulvar lichen sclerosus (VLS). The chronic and recurrent nature of VLS requires control of recurrences at an early stage. In this paper, a non-invasive multimodal optical coherence tomography (OCT) method was used to control for early histological signs of VLS recurrence after systemic PDT using Photodithazine®. To interpret the OCT data, a histological examination was performed before PDT and 3 months after PDT. Two groups of patients were identified: with early histological signs of VLS recurrence (Group I, n = 5) and without histological signs of VLS recurrence (Group II, n = 6). We use structural OCT, OCT angiography, and OCT lymphangiography throughout 6 months after PDT to visually assess the skin components and to quantitatively assess the dermis by calculating the depth-resolved attenuation coefficient and the density of blood and lymphatic vessels. The OCT data assessment showed a statistically significant difference between the patient groups 3 months after PDT. In Group II, all the studied OCT parameters reached maximum values by the 3rd month after PDT, which indicated recovery of the skin structure. At the same time, in Group I, the values of OCT parameters did not approach the values those in Group II even after 6 months. The obtained results of multimodal OCT can be used for non-invasive control of early histological recurrence of VLS after systemic PDT and for adjusting treatment tactics in advance, without waiting for new clinical manifestations of the disease.

Characterization of Acne-Prone Skin with Reflectance Confocal Microscopy and Optical Coherence Tomography and Modifications Induced by Topical Treatment and Probiotic Supplementation

The evaluation of acne-prone skin and absent-to-mild acne is difficult because this condition is not associated with a clinically definable situation. Previous studies showed that apparently healthy skin in patients with previous episodes of acne shows microcomedos and infundibular hyperkeratosis upon reflectance confocal microscopy (RCM) evaluation. Our aim was to characterize the subclinical and microscopic characteristics of acne-prone skin by means of RCM and dynamic optical coherence tomography (D-OCT) and evaluate microscopic changes induced by treatment. A group of 20 patients received a daily combined treatment over a period of 3 months, consisting of probiotic supplementation with three strains of 10⁹ colony-forming units of Lactobacillus (Lactobacillus reuteri, Lactobacillus casei subsp. rhamnosus, Lactobacillus plantarum) and a combined topical product of azelaic and hydroxypinacolone retinoate (HPR). Clinical evaluations and non-invasive imaging acquisitions using VISIA^® System, RCM, and D-OCT were performed at baseline, and after 4 and 12 weeks. The total number of clinically evident non-inflammatory lesions decreased during treatment from 11.5 to 7.3 (p < 0.05). There was also an evident reduction in microscopic acne features at RCM and D-OCT, such as the number of small bright follicles, large bright follicles and vascular threshold density at 300 μm and 500 μm depths. The types and extent of microscopic alterations in acne-prone skin patients may not be evident by clinical scores. Patients with low investigator global assessment (IGA) grades are a heterogeneous population, characterized by different microscopic skin features. Acne-prone skin is susceptible to treatment, and RCM and D-OCT imaging are sensitive tools to objectively monitor subclinical skin changes.

The role and safety of UVA and UVB in UV-induced skin erythema

Background

Different wavelengths of ultraviolet (UV) light cause skin damage through different mechanisms. Minimal erythema dose (MED) is usually used to clinically evaluate skin sensitivity to ultraviolet radiation by inducing skin erythema using ultraviolet B (UVB) or ultraviolet A (UVA) + UVB.

Aims

In this study, we detected changes in the blood flow at the MED erythema caused by UVB and UVA + UVB radiation through optical coherence tomography (OCT) to explain the role of different bands of ultraviolet rays in erythema induction.

Methods

Two MED irradiation areas on the subjects' back were irradiated with UVB alone or UVA + UVB (UVA: UVB = 8:1). The absolute energy of UVB remained the same in UVB and UVA+UVB. At 24 h after the irradiation, the changes in the blood flow in the MED area were detected using OCT.

Results

Compared with the blank control, the maximum blood flow depth, blood flow peak, and total blood flow of UVB-MED and UVA+UVB-MED were significantly increased. Notably, the maximum blood flow depth and blood flow peak of UVB-MED were higher than UVA+UVB-MED. There was no significant difference in total blood perfusion between UVA+UVB-MED and UVB-MED. Under the same UVB energy, the skin erythema caused by UVA + UVB was weaker than UVB alone.

Conclusions

The analysis of local blood flow by OCT showed that the peak and maximum depth of local blood flow caused by UVB alone were significantly higher than UVA + UVB.

Improve the dupilumab therapy evaluation with dermoscopy and high-frequency ultrasound in moderate-to-severe atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory disease. Monoclonal antibody dupilumab was approved to treat moderate-to-severe AD in recent years. An objective assessment of treatment response by skin imaging modality is adjuvant for clinical evaluations. This study aimed to explore the value of dermoscopy and high-frequency ultrasound (HFUS) imaging characteristics in treatment evaluation for moderate-to-severe AD patients treated with dupilumab.

METHODS

Moderate-to-severe AD patients refractory to conventional therapy were enrolled in the study. All patients went through at least a 16-week standardized treatment of dupilumab. Clinical scores (eczema area scoring index [EASI], SCOARD, numerical rating scale of pruritus, dermatology life quality index), dermoscopy, and HFUS examinations were conducted at 0, 2, 4, 8, 12, and 16 weeks of treatment. Erythema, scales, erosion, and pigmentation under dermoscopy were scored, and subepidermal low-echogenic band (SLEB) thickness under HFUS was measured as quantitative indexes. Descriptive analysis and mixed effect linear regression models were used for statistical analysis.

RESULTS

Sixteen patients were enrolled in the study and their average age was 45.63 ± 18.18 years. All clinical scores decreased with significant difference after 16-week treatment compared with baseline. All patients achieved EASI 50 (EASI score decreased by 50% or more), and 9/16 patients reached EASI 75 after 16-week treatment. Dermoscopy evaluation of erythema, scales and erosion scores were decreased, and the sign of pigmentation score was increased after treatment. For HFUS, the mean SLEB value was 0.51 ± 0.29 mm and decreased to 0.27 ± 0.15 mm after 16-week treatment (p < 0.01). SLEB value decreased linearly with treatment time and correlated with clinical scores. However, SLEB values of two patients were 0.57 and 0.68 mm at week 16, respectively, which were higher than the average, and one of the patients showed EASI 75.

CONCLUSION

Dermoscopy and HFUS were able to reveal deeper inflammation response than clinical scores in AD and can be an effective method to evaluate and monitor clinical improvement during dupilumab treatment for AD patients. The preliminary value of imaging methods for predicting the treatment endpoint of dupilumab remains to be verified.

Case report: Optical coherence tomography for monitoring biologic therapy in psoriasis and atopic dermatitis

Biologic therapies are increasingly used to treat chronic inflammatory skin diseases such as psoriasis and atopic dermatitis. In clinical practice, scores based on evaluation of objective and subjective symptoms are used to assess disease severity, leading to evaluation of treatment goals with clinical decisions on treatment initiation, switch to another treatment modality or to discontinue current treatment. However, this visual-based scoring is relatively subjective and inaccurate due to inter- and intraobserver reliability. Optical coherence tomography (OCT) is a fast, high-resolution, in vivo imaging modality that enables the visualization of skin structure and vasculature. We evaluated the use of OCT for quantification and monitoring of skin inflammation to improve objective assessment of disease activity in patients with psoriasis and atopic dermatitis. We assessed the following imaging parameters including epidermal thickness, vascular density, plexus depth, vessel diameter, and vessel count. A total of four patients with psoriasis or atopic dermatitis were treated with biologic agents according to current treatment guidelines. OCT was used to monitor their individual treatment response in a target lesion representing disease activity for 52 weeks. Psoriatic and eczema lesions exhibited higher epidermal thickness, increased vascular density, and higher vessel count compared to uninvolved skin. An upward shift of the superficial vascular plexus accompanied by smaller vessel diameters was seen in psoriasis in contrast to atopic dermatitis, where larger vessels were observed. A response to biologic therapy was characterized by normalization of the imaging parameters in the target lesions in comparison to uninvolved skin during the observation period of 52 weeks. Optical coherence tomography potentially serves as an instrument to monitor biologic therapy in inflammatory skin diseases. Imaging parameters may enable objective quantification of inflammation in psoriasis or atopic dermatitis in selected representative skin areas. OCT may reveal persistent subclinical inflammation in atopic dermatitis beyond clinical remission.

Riehl’s Melanosis: A Multimodality, In Vivo, Real-Time Skin Imaging Study with Cellular Resolution Optical Coherence Tomography and Advanced Skin Diagnosis System in a Tertiary Medical Center

Background: Riehl’s melanosis is a psychologically devastating hyperpigmentary disorder that typically occurs on the face and neck. The study of Riehl’s melanosis is limited due to its rarity, variable morphology, and lack of noninvasive diagnostic tools. Recent advances in skin imaging analysis and diagnostic systems improve diagnostic accuracy and enable the noninvasive, real-time evaluation of pigmentary disease. A comprehensive study of Riehl’s melanosis clinical morphology with multimodality and in vivo skin imaging systems has yet to be reported. Objectives: To investigate the clinical features and in vivo advanced skin imaging findings of Riehl’s melanosis. Methods: We retrospectively investigated the clinical characteristics, dermoscopic, and histopathological features of Riehl’s melanosis. We further utilized multimodality skin imaging analysis systems, including a cellular resolution optical coherence tomography (OCT) and new skin diagnosis system, to investigate the features of Riehl’s melanosis. In addition, we compared OCT findings with histopathological features and clinical assessment. Results: We evaluated 30 patients with Riehl’s melanosis at a tertiary medical center from 2010 to 2022. The average age was 47.7 ± 12.3 (mean ± SD) years, predominantly female patients (female: n = 23; male: n = 7). Cellular resolution OCT imaging from lesion skin shows increased melanocyte capping, disrupted basement membrane, telangiectatic blood vessels, and melanophages in the dermis. The advanced skin diagnosis system captured subclinical erythema of the skin, highlighting the inflammatory nature of the disease. The results correlated well with histopathological findings. Limitations: This is a single-center, cross-sectional study. Conclusions: We highlight the features of Riehl’s melanosis through a novel cellular resolution OCT and photographic skin diagnosis system. A multimodality skin diagnosis system can serve as a real-time, in vivo, noninvasive method for evaluating pigmentary disorders.

Dupilumab Improves Skin Barrier Function in Adults with Atopic Dermatitis: A Prospective Observational Study

Epidermal barrier dysfunction plays an important role in atopic dermatitis (AD). The difficulty of objectively assessing AD severity and the introduction of new biologicals into clinical practice highlight the need to find parameters to monitor clinical outcomes. The aim of this study is to evaluate the impact of dupilumab on skin barrier function and compare it with other treatments in patients with AD. A prospective observational study was conducted in adults with AD treated with topical corticosteroids (TCS), cyclosporine, or dupilumab. The main outcome measures after 16 weeks of treatment were Eczema Area and Severity (EASI)-50 (50% improvement in EASI), and transepidermal water loss (TEWL)-50 (50% improvement in TEWL). Forty-six patients with AD were included in the study. The proportion of patients who achieved EASI-50 at week 16 was significantly higher in patients receiving dupilumab (81.8% vs. 28.6% vs. 40%, p = 0.004). In eczematous lesions, TEWL decreased in patients receiving dupilumab (31.02 vs. 12.10 g·h−1·m−2, p < 0.001) and TCS (25.30 vs. 14.88 g·h−1·m−2, p = 0.047). The proportion of patients who achieved TEWL-50 at week 16 was higher for dupilumab than for cyclosporine or TCS. Temperature only decreased in the dupilumab group. Stratum corneum hydration increased in eczematous lesions and non-involved skin only in patients with dupilumab. In conclusion, dupilumab improves skin barrier function in patients with AD better than TCS or cyclosporine, both in eczematous lesions and in non-lesioned skin.

Line-field confocal optical coherence tomography of psoriasis, eczema and lichen planus: a case series with histopathological correlation

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.

Dermoscopy, Reflectance Confocal Microscopy and Optical Coherence Tomography Features of Acne: A Systematic Review

Noninvasive imaging techniques have recently outlined precise microscopic features of acne elementary lesions and accurate quantifications for disease severity staging and therapeutical efficacy follow-up. The aim of this review is to systematically describe current applications of dermoscopy, reflectance confocal microscopy (RCM), and optical coherence tomography (OCT) in acne vulgaris assessment and management. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. We included studies conducted on human subjects with elementary lesions of acne vulgaris, reporting assessment of the lesions with dermoscopy, RCM, and/or OCT. At present there are few large studies regarding acne and noninvasive imaging techniques, representing the main limitation of this review. Clinical examination represents the first line in acne diagnosis and treatment. However, dermoscopy, RCM, and OCT are further tools that can improve acne classification, monitoring of treatment, and pathophysiologic characterization. In the near future, dermoscopy, RCM, and OCT could become routinely used for the evaluation of acne vulgaris to provide a deeper knowledge of the disease and to guide the clinician in the prescription of tailored treatment protocols based on each patient’s characteristics.

Hidradenitis Suppurativa: morphologic and vascular study of nodular inflammatory lesions by means of optical coherence tomography

BACKGROUND

Hidradenitis Suppurativa (HS) is an inflammatory disease characterized by a recurrent-remission trend and clinical lesions that range from asymptomatic to inflamed, deep-seated nodules with scarring and suppuration.

OBJECTIVE

To identify morphologic and vascular features of HS nodules by means of dynamic optical coherence tomography (D-OCT) and to define if they are correlated to patient endotype and risk of disease progression.

METHODS

A set of standardized clinical pictures and D-OCT images were acquired from 57 inflammatory nodules of 40 patients affected by HS. A set of 20 clinical and D-OCT images were acquired from 20 healthy volunteers as a control group. The comparison of D-OCT features among HS and control group was analyzed. The correlation between HS patient endotype and D-OCT features of the lesions was calculated.

RESULTS

D-OCT enabled to identify vascular and morphological aspects characterizing HS nodular inflammatory lesions. In addition, several D-OCT features were significantly different among distinct disease endotypes.

CONCLUSION

The characterization of HS nodular inflammatory lesions through D-OCT, corresponding to blood vessel dilation and inflammatory associated hyper-vascularization, may have important clinical consequences in the assessment of HS risk of progression, therapeutic decisions and treatment efficacy monitoring.

High resolution imaging and quantification of the nailfold microvasculature using optical coherence tomography angiography (OCTA) and capillaroscopy: a preliminary study in healthy subjects

BACKGROUND

A wide range of diseases, such as systemic sclerosis, can be diagnosed by imaging the nailfold microcirculation, which is conventionally performed using capillaroscopy. This study applied optical coherence tomography angiography (OCTA) as a novel high resolution imaging method for the qualitative and quantitative assessment of the nailfold microvasculature, and compared OCTA imaging with capillaroscopy.

METHODS

For qualitative assessment, high resolution OCTA imaging was used to achieve images that contained a wide field of view of the nailfold microvasculature through mosaic scanning. OCTA imaging was also used to observe the characteristic changes in the microvasculature under external compression of the upper arm. For quantitative evaluation, the capillary density and the capillary diameter of the nailfold microvasculature were assessed with both OCTA and capillaroscopy by repeated measurements over 2 days in 13 normal subjects. The results were analyzed using the intraclass correlation coefficient (ICC).

RESULTS

OCTA imaging showed the typical nailfold microvasculature pattern, part of which was not directly seen with the capillaroscopy. OCTA imaging revealed significant changes in the nailfold microvasculature when a large external pressure was applied via arm compression, but no significant changes were observed using capillaroscopy. The capillary density measured by OCTA and capillaroscopy was 6.8±1.5 and 7.0±1.2 loops/mm, respectively, which was not significantly different (P=0.51). However, the capillary diameter measured by OCTA was significantly larger than that measured using capillaroscopy (19.1±2.5 vs. 13.3±2.3 µm, P<0.001). The capillary diameter measurements using OCTA and capillaroscopy were highly reproducible (ICC =0.926 and 0.973, respectively). While the capillary diameter measured with OCTA was significantly larger, it was rather consistent with the diameter measured using capillaroscopy (ICC =0.705).

CONCLUSIONS

This study demonstrated that OCTA is a potentially viable and reproducible tool for the imaging and quantification of the capillaries in the nailfold microvasculature. The results of this study provide a solid basis for future applications of OCTA in qualitative and quantitative assessment of nailfold microcirculation in vivo.

[Advances in optical coherence tomography]

Optical coherence tomography (OCT) has been able to establish itself in recent years not only in academic-scientific, but also in everyday dermatological practice. Its focus lies on epithelial tumors of the skin, which can be diagnosed intuitively and within a few seconds. Thus, basal cell carcinomas, actinic keratoses, and different stages of field cancerization can be diagnosed and monitored for response to therapy or possible recurrence. This often helps to avoid invasive sample extraction. Recently, the field of OCT and its latest advancement, dynamic OCT (D-OCT), has been expanded to include non-oncologic dermatological diseases. This encompasses inflammatory dermatoses and the analysis of physiological skin parameters such as hydration. Thanks to automated vascular imaging and the measurement of objective parameters such as epidermal thickness, blood flow at depth, optical attenuation coefficient, and skin roughness, more and more characteristics of the skin can be studied in a noninvasive and standardized way. New potential areas of application are eczema, contact allergic dermatitis, psoriasis, rosacea, telangiectasia, acute and chronic wounds, melasma and nevus flammeus but also melanocytic lesions.

In vivo examination of healthy human skin after short-time treatment with moisturizers using confocal Raman spectroscopy and optical coherence tomography: Preliminary observations

Skin is our barrier against environmental damage. Moisturizers are widely used to increase hydration and barrier integrity of the skin; however, there are contrasting observations on their in vivo effects in real-life settings. In cosmetic studies, corneometers and tewameters are traditionally used to assess skin hydration. In this study, two novel noninvasive diagnostic techniques, optical coherence tomography (OCT) and confocal Raman spectroscopy, were used to analyze stratum corneum and epidermal thickness (ET), water content, blood flow in function of depth, skin roughness, attenuation coefficient, natural moisturizing factor, ceramides and free fatty acids, cholesterol, urea, and lactates in 20 female subjects aged between 30 and 45 before and after 2 weeks application of a commercially available moisturizing lotion on one forearm. The untreated forearm served as control. A third measurement was conducted 1 week after cessation of moisturizing to verify whether the changes in the analyzed parameters persisted. We noticed a reduction in skin roughness, an increase in ceramides and free fatty acids and a not statistically significant increase in ET. As a conclusion, short time moisturizing appears insufficient to provide significant changes in skin morphology and composition, as assessed by OCT and RS. Novel noninvasive imaging methods are suitable for the evaluation of skin response to topical moisturizers. Further studies on larger sample size and longer treatment schedules are needed to analyze changes under treatment with moisturizers and to standardize the use of novel noninvasive diagnostic techniques.

Instrumental evaluation of skin barrier function and clinical outcomes during dupilumab treatment for atopic dermatitis: An observational study

BACKGROUND

Atopic dermatitis (AD) is a chronic, inflammatory skin disease characterized by pruritus, xerosis, and skin barrier dysfunction. Skin barrier alteration is associated with an increase in trans-epidermal water loss (TEWL) and reduction in skin hydration. Dupilumab is a monoclonal antibody targeting interleukin-13 modulating pro-inflammatory signal transduction, which has been approved for moderate to severe AD. The aim of this study is to evaluate the effects of Dupilumab on skin barrier functions, using non-invasive instruments and clinical evaluation.

MATERIALS AND METHODS

Thirty patients affected by moderate-severe AD, who had been administered dupilumab, were evaluated by clinical examination and through the instrumental measurements of TEWL and corneometry at the baseline (T0) and 8 weeks (T1) on lesional skin. The clinical evaluation was performed using the Eczema Area and Severity Index (EASI) score. Moreover, a Dermatology Life Quality Index (DLQI) and 7-day numeric rating scale (NRS) questionnaires were administered to each patient.

RESULTS

The instrumental parameters of skin barrier recovery confirmed the clinical improvement outcomes with a statistically significant reduction of TEWL at T1.

CONCLUSION

Our data confirm the clinical outcomes already reported in the literature and show that there was an inverse proportional correlation between TEWL levels and clinical severity after 8 weeks of treatment with dupilumab.

Applications and future directions for optical coherence tomography in dermatology

Optical coherence tomography (OCT) is a noninvasive optical imaging method that can generate high-resolution en face and cross-sectional images of the skin in vivo to a maximum depth of 2 mm. While OCT holds considerable potential for noninvasive diagnosis and disease monitoring, it is poorly understood by many dermatologists. Here we aim to equip the practising dermatologist with an understanding of the principles of skin OCT and the potential clinical indications. We begin with an introduction to the technology and discuss the different modalities of OCT including angiographic (dynamic) OCT, which can image cutaneous blood vessels at high resolution. Next we review clinical applications. OCT has been most extensively investigated in the diagnosis of keratinocyte carcinomas, particularly basal cell carcinoma. To date, OCT has not proven sufficiently accurate for the robust diagnosis of malignant melanoma; however, the evaluation of abnormal vasculature with angiographic OCT is an area of active investigation. OCT, and in particular angiographic OCT, also shows promise in monitoring the response to therapy of inflammatory dermatoses, such as psoriasis and connective tissues disease. We additionally discuss a potential role for artificial intelligence in improving the accuracy of interpretation of OCT imaging data.

Dupilumab use in atopic dermatitis and beyond in skin diseases

Atopic dermatitis (AD) is a chronic inflammatory condition that affects 5-10% of adults and 9-18% of children and its pathology is rooted in the Th-2-mediated immune response. Dupilumab is a fully human IgG4 monoclonal antibody that targets the IL-4 receptor alpha subunit that is endogenously bound by the Th-2 cytokines IL-4 and IL-13. Successful clinical trials of dupilumab showing marked improvements in clinical signs of AD, patient reported symptoms and quality of life measures led to its approval for clinical use for moderate-to-severe AD in 2017. This review details the current body of evidence on the drug's mechanism of action, pharmacology, clinical efficacy and safety as well as post market and real world use.