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

Combined Carbon Dioxide Laser with Photodynamic Therapy for Nodular Basal Cell Carcinoma Monitored by Reflectance Confocal Microscopy

Introduction: Basal cell carcinoma (BCC) represents around 80% of all malignant skin cancers worldwide, constituting a substantial burden on healthcare systems. Due to excellent clearance rates (around 95%), surgery is the current gold-standard treatment. However, surgery is not always possible or preferred by patients. Numerous non-surgical therapies, sometimes combined, have been associated with promising tumor free survival rates (80-90%) in non-melanoma skin cancers (NMSCs). Most research has enrolled superficial basal cell carcinomas (sBCCs), with limited recent studies also involving low-risk nodular BCCs (nBCCs). Given lower efficacy rates compared to surgery, close monitoring during the follow-up period is essential for patients treated with non-surgical therapies. Monitoring with dermoscopy is constrained by low sensitivity rates. Reflectance confocal microscopy (RCM) is more sensitive in monitoring non-surgically treated NMSCs. Case presentation: A 41-year-old woman with a single nBCC relapse following photodynamic therapy (PDT) located on the dorsum of the nose presented to our center. Given the aesthetically sensitive location of the lesion and the patient's preference for a non-surgical approach, a combined treatment of CO2 laser and PDT was prescribed. A superpulsed CO2 laser (power: 0.5-3 W, frequency: 10 Hz, spot size 2 mm) with two PDT sessions (2 weeks apart) were conducted. At 6 weeks follow-up, monitoring performed with RCM revealed a reduction but not eradication of basaloid tumor islands. Another 2 sessions of PDT were recommended. At 3, 12 and 30 months of follow-up, the nasal dorsum area of the previous nBBC lesion was noted to be slightly hypopigmented (observed clinically), with a mild erythematous background (observed by dermoscopy). RCM evaluation confirmed the absence of RCM BCC criteria. The cosmetic outcome was very much improved. Conclusions: Combined CO2 laser and PDT for the treatment of a localized nBCC on the dorsum of the nose of a 41-year-old proved to offer tumor free survival at 30-month follow-up, as monitored with RCM. RCM is useful for the evaluation of non-surgical therapies as it has comparably higher sensitivity than dermoscopy and is especially useful in cases of suspected late recurrence. Further studies are needed to validate ongoing tumor free survival following this combined nonsurgical approach in the treatment of nBCC.

The role of in vivo reflectance confocal microscopy for the management of acne: A systematic review

Acne diagnosis, severity assessment and treatment follow-up rely primarily on clinical examination. In vivo reflectance confocal microscopy (RCM) provides non-invasively, real-time images of skin lesions with a level of detail close to histopathology. This systematic literature review aims to provide an overview of RCM utility in acne and a summary of specific features with clinical application that may increase objectivity in evaluating this condition. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for reporting our results. We systematically searched three databases: PubMed, Clarivate and Google Scholar (January 2022). All included studies used RCM to investigate acne in human patients and reported the investigated skin area and type (acne lesions or clinically uninvolved skin), the substance used in the case of treatment. Our search identified 2184 records in the three databases investigated. After duplicate removal, 1608 records were screened, 35 were selected for full-text assessment, and 14 were included in this review. We used the QUADAS-2 tool to evaluate the risk of bias and applicability concerns. RCM was selected as the index test and clinical examination as the reference standard. The total number of patients from all studies was 291, with 216 acne patients and 60 healthy participants aged between 13 and 45 years. The 14 considered studies analysed 456 follicles from healthy participants, 1445 follicles from uninvolved skin in acne patients and 1472 acne lesions. Consistent RCM findings concerning follicles of acne patients reported across studies were increased follicular infundibulum size, thick, bright border, intrafollicular content and inflammation. Our analysis indicates that RCM is a promising tool for acne evaluation. Nevertheless, standardization, a unified terminology, consistent research methods and unitary reporting of RCM findings are necessary. PROSPERO registration number CRD42021266547.

Efficacy and safety of 1565-nm nonablative fractional laser combined with mucopolysaccharide polysulfate cream for erythematous acne scars

PURPOSE

To evaluate the efficacy and safety of 1565-nm nonablative fractional laser (NAFL) combined with mucopolysaccharide polysulfate (MPS) cream in the treatment of erythematous acne scars.

METHODS

A total of 28 subjects with erythematous acne scars from June 2021 to April 2022 were enrolled. One side of each subject's face was randomly assigned to be treated with 1565-nm NAFL (at 2 sessions with four-week intervals) combined with MPS cream (twice daily) for 8 weeks, and the other side with 1565-nm NAFL combined with placebo cream. CBS® images and parameters, dermoscopic images and the quantitative data processed by ImageJ software, and quantitative global scarring grading system (GSS) score were obtained at baseline and after treatment. Subjects' satisfaction assessment was performed after treatment. Adverse events were recorded during treatment.

RESULTS

In CBS® parameters, the red area, red area concentration, and smoothness were improved more significantly on the 1565-nm NAFL combined with MPS cream side than on the 1565-nm NAFL combined with placebo cream side after treatment (p = 0.015, p = 0.013, and p = 0.021). For dermoscopy, both scar area and scar redness achieved a significantly greater percentage of improvement on the side of 1565-nm NAFL combined with MPS cream than the side of 1565-nm NAFL combined with placebo cream after treatment (p = 0.005 and p = 0.041). The reduction of quantitative GSS score and Subjects' satisfaction assessment were similarly superior on the 1565-nm NAFL combined with MPS cream side. Temporary erythema was experienced by all subjects after each 1565-nm NAFL treatment. No subject reported intolerance or allergy to the cream during follow-up.

CONCLUSIONS

The combined application of 1565-nm NAFL and MPS cream could be an effective and safe treatment for erythematous acne scars. ImageJ software enables quantitative evaluation of dermoscopic images of acne scars.

The role of imaging technologies in the diagnosis of hidradenitis suppurativa

Hidradenitis suppurativa is a chronic, inflammatory, recurrent, and debilitating disease of the hair follicle. It presents with painful, deep-seated, inflamed lesions, such as nodules, abscesses, sinus tracts, and fistulas, generally located in the main folds. Clinical severity assessment alone can be reductive; noninvasive skin imaging technologies, such as ultrasound, magnetic resonance imaging, medical infrared thermography, computed tomography, and positron emission tomography, provide subclinical anatomical and functional details. These instrumental techniques confirm the clinical suspect, thus allowing an earlier diagnosis and improving patients' clinical evaluation, staging, and management. Finally, they might be helpful for preoperative mapping. In this contribution, we provide an overview of the current knowledge about noninvasive skin imaging techniques with a particular focus on ultrasonography, which is widely used thanks to its precision, versatility, and availability.

The Role of Reflectance Confocal Microscopy in the Diagnosis and Therapeutic Evaluation of Rare Disease Eosinophilic Pustular Folliculitis

Eosinophilic pustular folliculitis (EPF) is a rare skin disease for which the gold standard of diagnosis relies on the invasive examination of pathological tissue sections. However, due to its invasive nature, many patients tend to refuse this diagnostic test. In such situations, reflectance confocal microscopy (RCM) can be a valuable diagnosis tool. Reflectance confocal microscopy (RCM) can accurately identify the specific structures for biopsy and provide objective imaging data to evaluate clinical symptoms following treatment. Therefore, we present a case report demonstrating the utility of RCM in diagnosing and assessing the treatment of the rare disease EPF for reference.

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.

Reflectance Confocal Microscopy of Adult Periorificial Dermatitis: A Case Report

Periorificial dermatitis (PD) is an inflammatory disorder of the facial skin that mainly occurs around the mouth and manifests as erythema, papules, pustules, scales and other lesions. Special attention is needed in the clinical diagnosis of PD to distinguish it from acne, seborrheic dermatitis (SD), granulomatous rosacea (GR), sarcoidosis and childhood granulomatous periorificial dermatitis (CGPD). We used reflectance confocal microscopy (RCM) images of a patient with PD to assist in the diagnosis of PD. RCM of PD showed slight oedema of the spinous layer. Numerous dendritic cells, scattered hair follicular keratotic plugging and hair follicle dilatation were observed. The dilation and congestion of superficial dermis blood vessels, an increasing vascular density and accelerated blood flow, and a greater abundance of infiltrated inflammatory cells were also detected.

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.

Non-Invasive Diagnostic Techniques in Dermatology

The search to enhance the clinical diagnostic accuracy for identifying skin cancer has led to the development of non-invasive diagnostic techniques in dermatology including dermoscopy, reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) [...].