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There are many disorders of hair and scalp including
psoriasis, sebhorric dermatitis, alopecia areata,
androgenetic alopecia, chronic telogen, effluvium,
trichotillomania, and primary cicatrical alopecia.
The traditional methods used for detection of these
disorders are simple clinical examination and hair
pull tests, but often scalp biopsies become a must
- particularly in suspected cases of cicatrical alopecia,
alopecia areata incognita and telogen effluvium. However,
even pathological scalp biopsies do not always give
accurate results. Therefore, newer methods employing
superior detection devices such as dermoscopy becomes
essential in improving diagnostic accuracy in this
category of disorders.
Use of Dermoscopy for Evaluation
The use of dermoscopy has brought about considerable
improvement in the detection of melanoma. The handheld
dermoscope has revolutionized the manner in which
pigmented lesions are classified accurately for appropriate
therapy. It has also been seen that these useful instruments
can bring about a marked improvement in the manner
in which hair and scalp disorders are evaluated and
diagnosed.
Particular features, like wide range hair caliber
diversity in disorders like androgenetic alopecia
(AGA), are better observed with dermoscopy than with
the naked eye examination method. Moreover, dermoscopy
has made it possible to reveal newer features of the
disease like peripilar atropy in patients of AGA which
are vitally significant pathologically as well as
clinically.
What is Videodermoscopy?
This is an innovation and modification on the traditional
hand held dermoscopy. Videodermoscopy enables dermatologists
to view the scalp or skin surface at a rapid and higher
resolution and up to several times more magnified.
With this is the added ability of digitally recording
the viewed images and storing them for posterity.
Using videodermoscopy, a wide range of non-tumoral
scalp and hair conditions can be examined and certain
recognizable patterns can be readily identified.
The images in videodermoscopy are usually obtained
by computerized polarized light using lenses with
20 to 70 factors of magnification with x10 increments.
Alcohol is usually used as the interface liquid and
both epiluminescent as well as non epiluminescent
methods can be used. The digital images can be viewed
on a high-resolution monitor and important images,
which can be used later are stored.
The Features and Patterns revealed by Videodermoscopy
Vascular features are best observed employing the
epiluminescent method. There are three vascular features
noticeable. Interfollicular simple lasso shaped loops
are observed in isolation, interfollicular twisted
red loops are seen, which determine the presence of
psoriasis and sebhorric dermatitis giving rise to
the idea that vascular defects play an integral role
in the development of psoriasis. Red lines having
higher caliber than loops are also seen confirming
that it relates to subpapillary plexus. An even honey-comb
like pattern of pigment made up of brown rings is
observed in the areas where hair is thin or non existent
pointing to the problems of persistent and progressive
alopecia areata, AGA, lichen planopilaris, folliculitis
decalvans, chronic telogen effluvium or trichotillomania
and can be attributed to excessive exposure to the
sun.
With epiluminescent videodermoscopy, two peripilar
patterns of yellow dots and white dots were clearly
distinguishable. The yellow dots represent the distention
of affected follicles with keratinous material and
sebum, white dots determine sites of follicular degeneration
and define primary cicatrical alopecia.
Videodermoscopy as a Compelling Device
Currently videodermoscopy is not an economical method,
but as costs come down it will be a much-used instrument
in every clinic. This is due to the fact that several
patterns in the hair and scalp disorders have been
readily identified that are significant in determining
particular conditions opening new possibilities in
detection and subsequent therapy. Finding of determining
features of the two most commonly occurring hair and
scalp disorders of psoriasis and alopecia areata confirm
the fact that videodermoscopy is an inevitable detecting
instrument.
Though twisted loops are not found solely in cases
of psoriasis alone, a profusion of this feature at
a low magnification determines the diagnosis of this
disorder, as this feature is present in all cases
of psoriasis unlike in sebhorric dermatitis and DLE.
The presence or absence of twisted loops facilitates
the diagnosis in cases that are mild and partially
treated. Yellow dots are helpful in determining clinically
difficult cases and are determining features of alopecia
areata and advanced AGA. Only with the presence of
yellow dots can alopecia areata be confirmed and differentiated
from trichotillomania or telogen effluvium. Once determined
through videodermoscopy, the need for biopsy may be
reduced and is a boon especially in case of children
for whom biopsy can lead to trauma.
Apart from this, videodermoscopy can help by monitoring
the results of treatment, tracking of the development
of the disease and correlating prognostic determinants,
pathology and pathogenic factors with subsurface features.
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