DERMOSCOPY AND RECENTLY DEVELOPED IMAGING TECHNIQUES

Sep
2009
Vol. 28. No. 3

Introduction

The visual nature of dermatology has always lent itself perfectly to the plethora of available imaging techniques. The rapid expansion of visual technologies has provided further insight into the subtleties of our specialization. This issue of Seminars in Cutaneous Medicine and Surgery titled “Dermoscopy and Recently Developed Imaging Techniques” has been collated to demonstrate the broad scope of imaging techniques used within the field and their application in both clinical and research settings. As the title suggests, the core of this issue revolves around the art of dermoscopy and the relevance of its application in early detection of melanoma in addition to various other melanocytic and nonmelanocytic cutaneous neoplasms. Indeed, the morphologic classification based on dermoscopic features continues to evolve and enable more efficient monitoring, particularly of melanocytic lesions over time, in addition to refined aspects of clinico-pathologic correlation. The articles in this issue, all written by world-renowned experts in the field, outline the existing guidelines of dermoscopy in this regard as well as the current and future research focus of this technique. Perhaps one of the more recently conspicuous advances in dermoscopic evaluation has been the rise of teledermoscopy, which has facilitated the worldwide exchange of knowledge and expertise in dermatology and dermatopathology and provided the platform for second opinion. Technological advancement is perhaps most evident in regard to the imaging capacity of new generation cellular phones, which have quickly become almost ubiquitous among modern developed societies. Without a doubt, the potential feasibility of such an application is worth due consideration and an overview of its potential is also provided. While dermoscopy has cemented its place clinically in the superficial morphologic evaluation of pigmented lesions, the diagnostic standard remains to be histopathologic assessment requiring tissue biopsy for confirmation. A relatively new application in dermatology is confocal microscopy, a noninvasive instrument capable of generating horizontal planar sections of the epidermis and dermis in vivo. This tool, offering high-contrast cellular resolution images, will impact greatly on the current methods of clinical diagnosis of melanocytic lesions and nonmelanocytic skin cancers. The research and clinical applications of this exciting method will also be detailed presently. Other in vivo techniques, namely multiphoton laser scanning microscopy and optical coherence tomography, will also be outlined and help to complete the picture of the range of imaging techniques on the horizon within dermatology. While still in their early stages of potential application, the modern imaging techniques hold great potential within the field of dermatology. When combined with the current knowledge, morphologic evaluation may revolutionize the validity of diagnostic assessment. Furthermore, it is without a doubt that dermoscopy continues to provide dermatologists with a deepened insight into the many faces of pigmented skin lesions, strengthened by the continued refinement of techniques. It is with this spirit that this issue on dermoscopy and recently developed imaging techniques has been written.

Reflectance Confocal Microscopy in the Daily Practice

Alon Scope, MD | Harold S. Rabinovitz, MD | Margaret Oliviero, ARNP | Rainer Hofmann-Wellenhof, MD | Theresa Cao, DO | Verena Ahlgrimm-Siess, MD

Reflectance confocal microscopy (RCM) allows noninvasive imaging of the epidermis and
superficial dermis. Like dermoscopy, RCM acquires images in the horizontal plane (en
face), allowing assessment of tissue pathology underlying dermoscopic structures of
interest at a cellular-level resolution. Thus, clinicians using dermoscopy may find RCM to
be particularly useful. Our aim was to show the value of RCM for diagnosis and management
decisions related to pigmented and nonpigmented skin neoplasms seen in daily
practice. Six cases of clinically and dermoscopically equivocal skin lesions, for which RCM
facilitated making the correct diagnosis, are presented. Final diagnoses were made based
on histopathologic analysis. Three flat pigmented skin lesions with dermoscopic signs
of regression showed distinct RCM features that allowed their correct classification as
pigmented basal cell carcinoma, pigmented actinic keratosis, and melanoma on sundamaged
skin. A flat nonpigmented skin lesion on the face, which did not show distinct
clinical or dermoscopic features, was correctly diagnosed as basal cell carcinoma based on
RCM findings. In addition, the response of a pigmented actinic keratosis and a melanoma
in situ on sun-damaged skin to noninvasive topical treatment was monitored using RCM.
RCM is a promising and practical imaging tool for the diagnosis and follow-up of pigmented
and nonpigmented skin lesions.
Semin Cutan Med Surg 28:180-189 © 2009 Elsevier Inc. All rights reserved.

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Multiphoton Laser Scanning Microscopy—A Novel Diagnostic Method for Superficial Skin Cancers

John Paoli, MD, PhD | Mari Smedh, MSc, PhD | Marica B. Ericson, MSc, PhD

The increasing incidence of skin cancer and the importance of early diagnosis is a
challenge, which requires the development of reliable, cost-effective, noninvasive, diagnostic
techniques. Several such methods based on optical imaging techniques are available
and currently being investigated. A novel method in this field is multiphoton laser
scanning microscopy (MPLSM). This technique is based on the nonlinear process of
2-photon excitation of endogenous fluorophores, which can be used to acquire horizontal
optical sectioning of intact biological tissue samples. When studying human skin, MPLSM
provides high-resolution fluorescence imaging, allowing visualization of cellular and subcellular
structures of the epidermis and upper dermis. This review covers the application of
MPLSM as a diagnostic tool for superficial skin cancers, such as basal cell carcinomas,
squamous cell carcinoma in situ, and melanomas. MPLSM has also been applied in other
research areas related to skin, which will be mentioned briefly. The morphologic features
observed in MPLSM images of skin tumors are comparable to traditional histopathology.
Safety issues, limitations, and further improvements are discussed. Although further investigations
are required to make MPLSM a mainstream clinical diagnostic tool, MPLSM
has the potential of becoming a noninvasive, bedside, histopathologic technique for the
diagnosis of superficial skin cancers.
Semin Cutan Med Surg 28:190-195 © 2009 Elsevier Inc. All rights reserved.

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Optical Coherence Tomography for Imaging of Skin and Skin Diseases

G.B.E. Jemec, MD, DMSci | L. Thrane, MSci, PhD | Mette Mogensen, MD, PhD | P.E. Anderson, MscEE, PhD | T.M. Joergensen, MscEE, PhD

Optical coherence tomography (OCT) is an emerging imaging technology based on light
reflection. It provides real-time images with up to 2-mm penetration into the skin and a
resolution of approximately 10 m. It is routinely used in ophthalmology. The normal skin
and its appendages have been studied, as have many diseases. The method can provide
accurate measures of epidermal and nail changes in normal tissue. Skin cancer and other
tumors, as well as inflammatory diseases, have been studied and good agreement found
between OCT images and histopathological architecture. OCT also allows noninvasive
monitoring of morphologic changes in skin diseases and may have a particular role in the
monitoring of medical treatment of nonmelanoma skin cancer. The technology is however
still evolving and continued technological development will necessitate an ongoing evaluation
of its diagnostic accuracy. Several technical solutions are being pursued to further
improve the quality of the images and the data provided, and OCT is being integrated in
multimodal imaging devices that would potentially be able to provide a quantum leap to the
imaging of skin in vivo.
Semin Cutan Med Surg 28:196-202 © 2009 Elsevier Inc. All rights reserved.

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Mobile Teledermoscopy—Melanoma Diagnosis by One Click?

Alexandra M.G. Brunasso, MD | Cesare Massone, MD | H. Peter Soyer | Terri M. Campbell

Mobile telemedicine integrates wireless communications for different telemedical applications,
such as mobile phones and personal digital assistants, and with the implementation of modern
wireless telecommunication, wireless local area network and satellite communication is a
reality. New generation cellular phones or personal digital assistants have overcome limitations
of image quality seen in older devices and, with dermatology being a visual profession, mobile
teledermatology is perhaps the most recent development in this field. Mobile teledermatology
may provide a triage service aimed toward management of patients with emergent skin disease
or for follow-up with patients requiring systemic treatment. Teledermoscopy enables rapid
transmission of dermoscopic images via e-mail or specific web-application and studies have
demonstrated a high, 91%, concordance between face-to-face diagnosis and remote diagnosis
of such images. Further to this, telediagnosis of melanocytic skin neoplasms achieved a
diagnostic accuracy of 83% versus the conventional histopathologic diagnosis. Mobile teledermoscopy
is the combination of such approaches enabling transfer of images captured with
cellular phones coupled with a pocket dermatoscope and preliminary studies have demonstrated
the feasibility and potential of its use in triage of pigmented lesions. Such applications
are of benefit to physicians in enabling easy storage of data for follow-up or referral of images
for expert second opinion and may facilitate a “person-centered health system” for patients
with numerous moles and pigmented skin lesions who could forward images for evaluation. The
incidence of skin cancers has reached epidemic proportions among whites and the trend is still
going upward. Mobile teledermatology and teledermoscopy may be implemented as a triage or
screening tool for malignant tumors to facilitate early detection and diagnosis, which is crucial
for improved patient outcomes. While the legal aspects concerning teleconsultations need to
be evaluated, the communications technologies provide a unique opportunity for physicians
and patients alike and we foresee a place for these tools in dermatology soon.
Semin Cutan Med Surg 28:203-205 © 2009 Elsevier Inc. All rights reserved.

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