Category: Dermatology

Noninvasive diagnostic tools, such as Trichoscan®, reflectance confocal microscopy (RCM), and optical coherence tomography (OCT), are efficient methods of hair shaft and growth evaluation. The aim of this study was to carry out a comparative assessment of these three medical procedures by measuring the hair shaft and hair growth after hair removal for a defined period of five days. The application of these techniques was demonstrated by measuring hair growth on the lower leg of six female volunteers. After removal of the hair shaft with a shaving system, the hair follicle infundibula and the length of the growing hairs were ...

Background  Optical coherence tomography (OCT) allows real-time, in vivo examination of basal cell carcinoma (BCC). A new high definition OCT with high lateral and axial resolution in a horizontal (en-face) and vertical (slice) imaging mode offers additional information in the diagnosis of BCC and may potentially replace invasive diagnostic biopsies. Objectives  To define the characteristic morphologic features of BCC by using high definition optical coherence tomography (HD-OCT) compared to conventional histology. Methods  A total of 22 BCCs were examined preoperatively by HD-OCT in the en-face and slice imaging mode and characteristic features were evaluated in comparison to the histopathological findings ...

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 ...

New bioengineering techniques provide noninvasive opportunities to evaluate clinically the application of various products on the skin. The skin barrier function and its integrity can be studied by transepidermal water loss, stratum corneum water content, transcutaneous flux of carbon dioxide and oxygen, and transepidermal movement of ions, particularly chloride, potassium, and hydrogen ions. The benefits of noninvasive techniques are due not only to their lack of skin barrier destruction but also to their potential for early detection of any subclinical effects not detected by the naked eyes

Background/Aims: Full-field optical coherence tomography (FFOCT) is a new imaging technology that can provide 3D micron-level resolution and is suited for high-resolution imaging of biological tissue. The aim of this study was to evaluate its capacity and potential for imaging human epidermis and dermis and various skin pathologies in ex vivo and in vivo conditions. Methods: Non-fixed and fixed samples of normal and pathological skin and normal in vivo skin were imaged with a FFOCT system and compared to histological slides. Results: The epidermis and adnexae, the collagen bundles of the dermis and the hypodermis could be identified through ...

Background/Aims : Full-field optical coherence tomography (FFOCT) is a new imaging technology that can provide 3D micron-level resolution and is suited for high resolution imaging of biological tissue. The aim of this study is to evaluate its capacity and potential for imaging human epidermis and dermis and various skin pathologies in ex- and in-vivo conditions. Methods : Non fixed and fixed samples of normal and pathological skin and normal in-vivo skin were imaged with a FFOCT system and compared to histological slides. Results: The epidermis and adnexae, the collagen bundles of the dermis and the hypodermis could be identified through architectural ...

Abstract  In this study, a swept-source optical coherence tomography (SS-OCT) system with a Fourier domain mode locking (FDML) laser is proposed for a dermatology study. The homemade FDML laser is one kind of frequency-sweeping light source, which can provide output power of >20 mW and an output spectrum of 65 nm in bandwidth centered at 1300 nm, enabling imaging with an axial resolution of 12 μm in the OCT system. To eliminate the forward scans from the laser output and insert the delayed backward scans, a Mach-Zehnder configuration is implemented. Compared with conventional frequency-sweeping light sources, the FDML laser can ...

We have investigated depth-resolved cellular structures of unmodified fresh human scalp hairs with ultrahigh-resolution full-field optical coherence tomography (FF-OCT). The Linnik-type white light interference microscope has been home-implemented to observe the micro-internal layers of human hairs in their natural environment. In hair shafts, FF-OCT has qualitatively revealed the cellular hair compartments of cuticle and cortex layers involved in keratin filaments and melanin granules. No significant difference between black and white hair shafts was observed except for absence of only the melanin granules in the white hair, reflecting that the density of the melanin granules directly affects the hair color. Anatomical ...

In this paper, the features of the intensity-based Doppler variance (IBDV) method were analyzed systemically with a flow phantom. The effects of beam scanning density, flow rate and the time interval between neighboring A-lines on the performance of this method were investigated. The IBDV method can be used to quantify the flow rate and its sensitivity can be improved by increasing the time interval between the neighboring A-lines. A higher sensitivity IBDV method that applies the algorithm along the slower scan direction was proposed. In comparison to laser speckle imaging maps of blood flow, we demonstrated the ability of the ...

The investigators will obtain human skin specimen (sized approximately 1 cm x 1 cm) for dermatological surgical patients in National Taiwan University Hospital, after informed consent was obtained. Human skin keratinocytes, fibroblasts, and melanocytes will be cultured from the human skin specimen. The three dimensional images of these cultured cells will be observed by a ultra-high resolution 3-dimensional optical coherence tomography.

Abstract  The characteristics of skins in different aging processes were obtained by optical coherence tomography (OCT) single scattering model, and their optical parameters were analyzed quantitatively. Significant differences were found in epidermis thickness and attenuation coefficients in chronological aging skins and photonaging skins. These parameters can be served as indicators of skin type as well as the progress of aging. These results are valuable to the study of aging skin, and they could further help to understand the mechanism of aging.

Michelson Diagnostics (‘Michelson’) has announced an investment of £607k by shareholders Octopus Investments (‘Octopus’), Catapult Venture Managers (‘Catapult’) and individual investors, especially London Business Angels. The investment, which was an extension to the £1.92M investment in October 2011, will be used to further expand sales & support infrastructure in both USA and Europe, as Michelson’s installed base of ‘VivoSight’ skin cancer laser scanners continues to expand. The Company’s first product based on its patented multi‐beam optical coherence tomography (OCT) technology, the VivoSight scanner, is expected to revolutionise the market for the non‐invasive diagnosis and treatment of ...

Cutaneous aging is a complicated biological process affecting different constituents of skin, which can be divided into two types: the chronological aging and the photo-aging. The two cutaneous aging processes often co-exist accompanying with each other. The effects are often overlapped including changes in epithelium and dermis. The degeneration of collagen is a major factor in dermal alteration with aging. In this study, multiphoton microscopy (MPM) with its high resolution imaging and optical coherence tomography (OCT) with its depth resolved imaging were used to study the anti-aging dermatology in vivo. It was attempted to make the optical parameter and texture ...

The incidence of melanoma is on the rise, and early detection of disease is imperative to reduce mortality. Dermatologists are key players in the early detection of melanoma; however, some clinicians rely on their clinical examination without any additional diagnostic tools to make this important diagnosis. Certain patients, such as atypical nevus patients, have more complicated mole examinations, making the diagnosis of melanoma difficult, whereas some melanomas, such as amelanotic melanomas, can be diagnostically challenging. The goal of the clinician is to detect melanoma with the highest accuracy, while avoiding unnecessary biopsies. Using diagnostic melanoma tools as an adjunct to ...

An integrated multimodal optical microscope is demonstrated for high-resolution, structural and functional imaging of engineered and natural skin. This microscope incorporates multiple imaging modalities including optical coherence (OCM), multi-photon (MPM), and fluorescence lifetime imaging microscopy (FLIM), enabling simultaneous visualization of multiple contrast sources and mechanisms from cells and tissues. Spatially co-registered OCM/MPM/FLIM images of multi-layered skin tissues are obtained, which are formed based on complementary information provided by different modalities, i.e., scattering information from OCM, molecular information from MPM, and functional cellular metabolism states from FLIM. Cellular structures in both the dermis and epidermis, especially different morphological ...