Confocal laser-scanning capillaroscopy: a novel approach to the analysis of skin capillariesin vivo

Nailfold capillary patterns correlate with age, gender, lifestyle habits, and fingertip temperature

Nailfold capillaroscopy is a simple and noninvasive imaging tool to visualize the pattern of capillaries. Microvascular abnormalities have been previously observed in autoimmune disease such as systemic sclerosis and diabetes. Thus, early detection of microvascular dysfunction or changes has promising way for the one of the disease preventions. In this study, for routine health checkups, we evaluated the relationship between the structure of nailfold capillaries and lifestyle habits in healthy participants. First, we analyzed the correlation of structural parameters of nailfold capillaries with values of responses to questions on their lifestyle habits in 224 participants. The results suggested that an unhealthy lifestyle, including poor sleeping habits, smoking, intense exercise, and drinking alcohol, causes a change in the pattern of nailfold capillaries. We then investigated whether the pattern of nailfold capillaries changed after a conscious improvement in lifestyle habits. One to two weeks after the self-improvement of lifestyle habits, the hairpin loops sharpened or straightened. In conclusion, this study is the first report indicating a correlation between the structure of nailfold capillaries and lifestyle habits in a non-clinical population. The simple, inexpensive, and noninvasive method using nailfold microscopy can be employed for routine health checkups everywhere even at a bedside.

The value of ultrahigh resolution OCT in dermatology - delineating the dermo-epidermal junction, capillaries in the dermal papillae and vellus hairs

Optical coherence tomography (OCT) imaging of the skin is gaining recognition and is increasingly applied to dermatological research. A key dermatological parameter inferred from an OCT image is the epidermal (Ep) thickness as a thickened Ep can be an indicator of a skin disease. Agreement in the literature on the signal characters of Ep and the subjacent skin layer, the dermis (D), is evident. Ambiguities of the OCT signal interpretation in the literature is however seen for the transition region between the Ep and D, which from histology is known as the dermo-epidermal junction (DEJ); a distinct junction comprised of the lower surface of a single cell layer in epidermis (the stratum basale) connected to an even thinner membrane (the basement membrane). The basement membrane is attached to the underlying dermis. In this work we investigate the impact of an improved axial and lateral resolution on the applicability of OCT for imaging of the skin. To this goal, OCT images are compared produced by a commercial OCT system (Vivosight from Michaelson Diagnostics) and by an in-house built ultrahigh resolution (UHR-) OCT system for dermatology. In 11 healthy volunteers, we investigate the DEJ signal characteristics. We perform a detailed analysis of the dark (low) signal band clearly seen for UHR-OCT in the DEJ region where we, by using a transition function, find the signal transition of axial sub-resolution character, which can be directly attributed to the exact location of DEJ, both in normal (thin/hairy) and glabrous (thick) skin. To our knowledge no detailed delineating of the DEJ in the UHR-OCT image has previously been reported, despite many publications within this field. For selected healthy volunteers, we investigate the dermal papillae and the vellus hairs and identify distinct features that only UHR-OCT can resolve. Differences are seen in tracing hairs of diameter below 20 μm, and in imaging the dermal papillae where, when utilising the UHR-OCT, capillary structures are identified in the hand palm, not previously reported in OCT studies and specifically for glabrous skin not reported in any other in vivo optical imaging studies.

Simultaneous dermal matrix and autologous split-thickness skin graft transplantation in a porcine wound model: a three-dimensional histological analysis of revascularization

Despite the popularity of a simultaneous application of dermal matrices and split-thickness skin grafts, scarce evidence exists about the process of revascularization involved. In this study, we aimed at analyzing the progression of revascularization by high-resolution episcopic microscopy (HREM) in a porcine excisional wound model. Following the surgical procedure creating 5 × 5 cm(2) full-thickness defects on the back, one area was covered with an autologous split-thickness skin graft alone (control group), the other with a collagen-elastin dermal matrix plus split-thickness skin graft (dermal matrix group). Two skin biopsies per each group and location were performed on day 5, 10, 15, and 28 postoperatively and separately processed for H&E as well as HREM. The dermal layer was thicker in the dermal matrix group vs. control on day 5 and 28. No differences were found for revascularization by conventional histology. In HREM, the dermal matrix did not appear to decelerate the revascularization process. The presence of the dermal matrix could be distinguished until day 15. By day 28, the structure of the dermal matrix could no longer be delineated and was replaced by autologous tissue. As assessed by conventional histology and confirmed by HREM, the revascularization process was comparable in both groups, notably with regard to the vertical ingrowth of sprouting vessels. The presented technique of HREM is a valuable addition for analyzing small vessel sprouting in dermal matrices in the future.

High-resolution episcopic microscopy (HREM): a tool for visualizing skin biopsies

We evaluate the usefulness of digital volume data produced with the high-resolution episcopic microscopy (HREM) method for visualizing the three-dimensional (3D) arrangement of components of human skin, and present protocols designed for processing skin biopsies for HREM data generation. A total of 328 biopsies collected from normally appearing skin and from a melanocytic nevus were processed. Cuboidal data volumes with side lengths of ~2×3×6 mm3 and voxel sizes of 1.07×1.07×1.5 µm3 were produced. HREM data fit ideally for visualizing the epidermis at large, and for producing highly detailed volume and surface-rendered 3D representations of the dermal and hypodermal components at a structural level. The architecture of the collagen fiber bundles and the spatial distribution of nevus cells can be easily visualized with volume-rendering algorithms. We conclude that HREM has great potential to serve as a routine tool for researching and diagnosing skin pathologies.

In-vivo imaging of psoriatic lesions with polarization multispectral dermoscopy and multiphoton microscopy

Psoriasis is a skin autoimmune disease characterized by hyperkeratosis, hyperproliferation of the epidermis and dilatation of dermal papillary blood vessels. Healthy skin (5 volunteers) and psoriatic lesions (3 patients) were visualized in vivo, with high contrast and resolution, with a Polarization Multispectral Dermoscope and a Multiphoton Microscope. Psoriatic features were identified and quantified. The effective diameter of the superficial blood vessels was measured at 35.2 ± 7.2 μm and the elongated dermal papillae had an effective diameter of 64.2 ± 22.6 μm. The methodologies developed could be employed for quantitative diagnostic purposes and furthermore serve as a monitoring method of the effect of personalized treatments.

Clinical Trial Study in the Treatment of Nail Psoriasis with Pulsed Dye Laser

Abstract Objective: The treatment options for nail psoriasis have been limited, and the management of nail psoriasis has been challenging for physicians. This study aimed at evaluating the effect of different pulse durations in the treatment of nail psoriasis with the 595-nm PDL to determine the optimal pulse duration. Methods: Forty patients with bilateral fingernail psoriasis were recruited and completed a 6-month trial. PDL was applied on the proximal and lateral nailfolds based on random assignment. Eghity nails were treated with 6-millisecond pulse duration and 9 J/cm(2) whereas 80 nails were treated with 0.45-millisecond pulse duration and 6 J/cm(2). Nail Psoriasis Severity Index (NAPSI) was used to assess the clinical outcome from pretreatment and posttreatment photographs. Results: After 6 months of first treatment, there was a significant reduction in overall NAPSI, nail matrix NAPSI, and nail bed NAPSI scores from baseline in both groups; however, no significant difference was found between the two pulse duration groups. Side effects were mild including transient petechiae and hyperpigmentation. Conclusion: Both the longer 6-millisecond and shorter 0.45-millisecond pulses of PDL (595 nm) have been clinically proven to be effective for the treatment of nail matrix and nail bed psoriasis.

Noninvasive in vivo detection and quantification of Demodex mites by confocal laser scanning microscopy

BACKGROUND

In many Demodex-associated skin diseases Demodex mites are present in abundance and seem to be at least partially pathogenic. So far all diagnostic approaches such as scraping or standardized superficial skin biopsy are (semi-)invasive and may cause discomfort to the patient.

OBJECTIVES

To see whether confocal laser scanning microscopy (CLSM) - a noninvasive method for the visualization of superficial skin layers - is able to detect and quantify D. folliculorum in facial skin of patients with rosacea.

METHODS

Twenty-five patients (34-72 years of age) with facial rosacea and 25 age- and sex-matched normal controls were examined by CLSM. Mosaics of 8 × 8 mm and 5 × 5 mm were created by scanning horizontal layers of lesional skin and quantification of mites per follicle and per area as well as follicles per area was performed.

RESULTS

In all patients D. folliculorum could be detected by CLSM and presented as roundish or lengthy cone-shaped structures. CLSM allowed the quantification of Demodex mites and revealed significant differences (P < 0·0001): the mean number of mites was 165·4 per 8 × 8 mm area and 94·2 per 5 × 5 mm area in the patients compared with 34·7 and 22·4, respectively, in the controls. The corresponding mean number of mites per follicle was 0·7 and 0·8, respectively, in the patients and 0·1 and 0·2, respectively, in the controls.

CONCLUSIONS

With the help of CLSM it is possible to detect, image and quantify Demodex mites noninvasively in facial skin of patients with rosacea.

Confocal laser scanning microscopy as a new valuable tool in the diagnosis of onychomycosis - comparison of six diagnostic methods

Onychomycosis is common and can mimic several different nail disorders. Accurate diagnosis is essential to choose the optimum antifungal therapy. The aim of this study was to evaluate the use of confocal laser scanning microscopy (CLSM) and optical coherence tomography (OCT) as new non-invasive diagnostic tools in onychomycosis and to compare them with the established techniques. In a prospective trial, 50 patients with suspected onychomycosis and 10 controls were examined by CLSM and OCT. Parallel KOH preparation, culture, PAS-staining and PCR were performed. PCR showed the highest sensitivity, followed by CLSM, PAS and KOH preparation. OCT offered the second best sensitivity but displayed the lowest specificity. CLSM and KOH preparation showed a high specificity and CLSM offered the best positive predictive value, similar to KOH preparation and OCT. Fungal culture showed the lowest sensitivity and the worst negative predictive value, yet culture and PCR are the only techniques able to identify genus and species. In summary, CLSM was comparable to PAS staining and superior to KOH preparation. Due to the low specificity we assess OCT not as appropriate. In the differentiation of species PCR outplays the fungal culture in terms of time and sensitivity.