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In its most basic configuration, a dermatoscope can
cost as little as $300 US. More complex dermatoscopes,
particularly those with digital imaging capabilities
can cost several thousand dollars. Which one is
right will depend on the dermatologist and the nature
of the dermatology clinic.
For a dermatology clinic
that caters to the general public on a small scale,
relatively cheap handheld dermatoscope devices may
fulfill all of the dermatologist’s requirements.
For larger clinics, particularly those involved
in research and clinical drug trials, a digital
dermatoscope may provide both diagnostic capabilities
and an excellent way to record skin lesions for
patient notes, research reports, or clinical trial
reports.
The price for a dermatoscope inevitably relates to
the functionality of the dermatoscope make and model.
The simplest, like a Heine Delta 10, provides the
bare basics, but a more expensive model may be easier
to use, give a better image, and enable more accurate
diagnosis.
Dermatoscope requirements
In
order to correctly evaluate skin lesions using a hand-held
dermoscope, it is essential to have adequate
magnification and illumination to allow the differential
structures to be clearly seen. At a minimum a 10x
optical magnification is required. Higher
magnifications are also available either by changing
the lens cluster or, with digital image taking dermatoscopes,
by using an optical zoom feature.
The optics in a dermoscope are worth considering.
Like cameras, the quality of lenses can be variable.
Lenses without blemishes are important to minimize
light scatter and improve image quality. While cheap
dermatoscope lenses can be obtained from the far east,
they may not give a superior result. German dermatoscopes
are well known for their good quality
lenses made
from
hardened
glass
or composites. Indeed, germany tends to lead the world
in lens quality in cameras and microscopes - albeit
closely followed by Japan.
Lighting is very important for effective use of a
dermatoscope. In the newer dermoscopes (for example
the Heine Delta 20, Dermogenius and Dermlite Foto)
the light sources are much improved compared to older
models. Now 6 or even 24 LEDs are employed to light
the field of view. The use of several LEDs is a significant
advance over the use of a single halogen light bulb
giving much better and more even lighting of the skin.
This
distinctly improves the image quality with regard
to color and visible differential structures compared
to older dermatoscopes (for example the Heine Delta
10). As such, a newer model with an LED light source
is a good investment, but somewhat more expensive
than the older, more basic models. Expect to pay $500-$1,000
for a handheld dermatoscope with good LED lighting
built in.
Digital dermatoscopes
Using a digital zoom (found on some modified camera
based dermatoscopes) is not suitable as this reduces
the resolution (number of pixels per unit area of
the image) of the image on the computer screen. A
digital zoom is actually just some software inside
the camera that takes a smaller proportion of the
original digital image and blows it up to the required
images size. So an image taken with a high digital
zoom magnification actually reduces the clarity of
an image and fails to provide any additional detail
in the image. In contrast, an optical zoom (found
on better quality digital camera based dermatoscopes
and specifically designed digital dermatoscopes) uses
lenses instead
of software to take a higher resolution image over
a smaller area of skin. An optical zoom ensures that
the number of pixels per unit area of an image stays
the same.
If
the dermatoscope is entirely digital and a computer
must be used to view the image (you cannot use your
own eyes to view the image directly through the dermatoscope
lens), then the resolution of the light sensing chip
becomes more
important.
Basically, the higher the number of pixels the better
the image quality. However, the more pixels involved,
the bigger
the images files produced and so the more powerful
the computer required to display the images. Correspondingly,
digital dermatoscopes with good imaging capabilities
can be a very expensive option. Some dedicated digital
dermatoscopes and their associated computer hardware
and software and easily amount to over $20,000.
If you don't need to take and store digital images,
a simple handheld dermatoscope is probably enough
for your needs. If you want to give your patients
more feedback, a digital dermatoscope attached to
a computer and printer can give them something to
take home - a surprisingly effective method of informing
patients as to their skin conditions. But of course
the cost is correspondingly more expensive. A cheaper
option than a dedicated digital dermatoscope (like
the Fotofinder range) is a modified digital camera
set up. Some (Like the Trichoscan system) are essentially
a good quality digital camera to which a hardened
glass close up lens extension and LED ring light
are attached with a screw thread that is put on some
digital
cameras.
The cost then is the cost of the digital camera ($200-400)
plus the close up lens extension ($200-$400) and an
LED ring light ($200). Buying a complete package
including image software runs to around $1,000.
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