Dermatoscopy

Looking through a DERMOSCOPE

Dr.Yogesh KalyanpadMumbai

DermatoscopySynonyms: Surface microscopy, epiluminescent microscopy, capillary microscopyTo magnify the surface features of the skinBeing non-invasive can be repeatedImages can be stored and studied laterUsed for decades for early diagnosis of melanomaCan be used for diagnosis of other disorders

IntroductionThe term dermatoscopy was coined by Saphier in 1920Pioneered in USA by Goldman in 1950s for diagnosis and follow up of melanocytic nevi and cutaneous melanomasTerminology defined by Bahmer in 1990 with Delta 10Enhances the most basic of fundamentals in clinical dermatology the visual inspectionNon-invasive and repeatableRecordable in standardized conditions for monitoring

Traditional Dermoscope

Hand-held deviceLight sourceContact plateLinkage fluid

Light sourceWhite lightHalogen lampWhite light multiple LEDsPolarizing LEDs

Comparison of dermoscopesVideodermoscopeHandheld dermocsopeComputer connection neededViewing easy as image is enlargedCapture device not neededVideo real time easyStorage, cataloguing and analysis easyCheck resolutionCheck light source

Computer not needed Viewing not easy Capture device neededContact plate and linkage fluid needed

Handheld videodermoscopeHandyGets used more frequentlyLooks attractiveUser friendlyGood magnificationLow resolutionNo polarized light

Hand-held Dermatoscope Hiene Delta 10 (Magnification 10X (can be variable)Dermaphot imaging system

Video Dermatoscope

Hiene Delta 20Contact platesBetter illumination and resolution

Historical background1663: Johan KohlhausStudied nail fold vessels with a microscope1920: Saphier ICoined Dermatoskopie 1933: Hinselmanninvented colposcopeStudied cutaneous ulcers & tumors1951: Goldman L invented monocular dermoscopeStudied nevi & melanomas 1987: Pehamberger HIntroduced Pattern Analysis for pigmented lesions1990: Bahmer FA et alCoined terminologies in dermoscopy with invention of Delta 10

What do I expect?Not what you see through a magnifying lensMagnification is much more than a lensUnexpected morphologic featuresJust like you go directly to high power of microscope

Pigment networkTrunk & extremities Represent melanin pigment in keratinocytes, or in melanocytes along the DE junctionReticulation = rete ridge patternHypomelanotic holes= tips of dermal papillae

Pseudonetwork FaceDue to interruption of lighter uniform pigment by follicular pattern

NORMAL PIGMENT NETWORK

PSEUDO NETWORK ON FACE

Dots/ Granules small round structures (< 0.1mm in dia.)

Black-pigment in str. corneum & upper epidermis

Brown-focal melanin accumulation at DE jn.

Gray blue (peppering)- tiny melanin granules in papillary dermis

Steel blue or blue melanophages in deep papillary or reticular dermis

Globules Globules are large dotsCorrespond to nests of melanocytes, melanin &/or melanophages on both sides of DEjunction

Blotches Abrown-black poorly circumscribed area

Melasma types

In individuals with dark-brown skin, examination with a Wood s light does not localize pigment, and these patients are thus classified as indeterminate

Role of Dermoscopy in Melasma

Differentiating from LPP, Nevus of Ota, ochronosis etc.

Identifying early cases (speckled) that look like freckles

Deciding depth of melasma especially in dark skinned individuals where Woods lamp is of little help

Monitor efficacy of therapy standardized photos

Pick up complications early e.g. atrophy, depigmentation, telangiectasia, exogenous ochronosis, steroid dermatitis etc.

Speckled melasma scattered islands of reticular network of light brown or tan color with dark brown fine granules scattered on the surface

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Large patches of melasma >2 cm - diffuse reticular pigmentation , - arcuate, star-like, annular & granular dark brown structures in perifollicular regions but sparing the follicles

Scabies burrowLinear borrow with scaling under white light and polarizing light

Do I really need to do this?Doctors are committed to delivering a continually improving standard of careStandard of care begins with standard of diagnosisDermoscope can be a dermatologists sthethoscope

Thank You

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