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Dr Jane Grant discusses new and
emerging technologies in dermatology
Jane Grant-Kels MD, is Director of
Dermatopathology and Chair of
the Melanoma Signature Program
at the University of Connecticut
Health Center, and an Advisory
Board Member of
PracticeUpdate
Dermatology
.
SYM S035 – New and emerging technologies in dermatology.
Jane Grant-Kels
This session reviewed current and evolving technologies available to help us differentiate
benign from malignant lesions without performing a biopsy.
Reflectance confocal microscopy
In vivo reflectance confocal microscopy (RCM) is a noninvasive optical imaging technique
that provides a high-resolution image of the skin to a depth of 200 to 300 μm (0.2–0.3 mm).
RCM relies on a low-power laser that emits near infrared light projected through a lens system.
To obtain an image of skin, RCM uses the different reflection indices of various structures to
produce a horizontally sectioned (ie, sections parallel to the skin surface) black-and-white image.
The resulting images are comparable to histopathology images but are obtained in vivo, without
performing a biopsy. I reviewed clinical applications of the VivaScope 1500, or the wideprode
traditional RCM that has recently been awarded CPT codes and can be used to evaluate 8 mm
x 8 mm areas on the skin. Dr Harold Rabinovitz from the University of Miami reported on the
handheld VivaScope 3000, which provides stacks of images through the skin that are only 1
mm x 1 mm in size. The handheld adaptor is most applicable to evaluate tumours on the eyes,
periorbital skin, mucosal surfaces, and curved surfaces of the face, which are difficult to capture
with the larger head of the VivaScope 1500. Both I and Dr Rabinovitz gave many examples of
how this technology can spare our patients unnecessary biopsies and improve our malignant to
benign biopsy ratio.
Electrical impedance spectroscopy
Dr Peter Mohr from Buxtehude, Germany, reviewed his data on the use of electrical impedance
spectroscopy (EIS) to differentiate benign from malignant lesions of the skin without biopsy.
EIS measures the overall resistance within tissue at alternating currents of various frequencies.
The resulting different measurements detect changes in cellular structure, cellular orientation,
cell sizes, and cell types. The ultimate score is calculated by the computer and reflects the
degree of atypia, helping to establish the difference between a benign nevus and melanoma
with a sensitivity of 97% and specificity of 35% and without a painful procedure. Of interest
is that the sensitivity for dermatopathology was 85% and the sensitivity for dermoscopy was
71% on the same lesions. Dr Mohr suggested that this new technology would be particularly
helpful in those melanomas that defy clinical and dermatoscopic diagnosis. The use of EIS in
dermatology clinics in Europe has been shown to reduce excisions by 40% to 50%.
Raman spectroscopy and photoacoustic tomography
Dr Eric Tkaczyk from Vanderbilt University reviewed the exciting future roles for Raman
spectroscopy and photoacoustic tomography. Raman spectroscopy is a technique that measures
inelastic scattering of monochromatic light. The light interacts with molecular vibrations that
result in a “fingerprint” of the biochemical compo-
sition of the tissue. Clinical applications include
imaging of topical drug delivery. Photoacoustic
tomography allows deep detection of melanin, hae-
moglobin, and oxygenation. Three-dimensional im-
aging of tissue results from light that is absorbed by
biological tissue and converted to transient heating,
which is then converted into ultrasonic waves. De-
tection of the ultrasonic waves yields a tomographic
image based on the photoacoustic effect. Dr Tkaczyk
demonstrated how photoacoustic microscopy could
identify melanoma metastases in lymph nodes in
lieu of sentinel lymph node biopsies! This new and
exciting technology is still only in the research lab
but someday will be applied in the clinic to reduce
procedures and enhance accuracy in early diagnosis.
© 2016 AMERICAN ACADEMY OF DERMATOLOGY
DECEMBER 2016
AAD 2016
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