2. Non invasive diagnostic
tool which visualizes subtle
clinical patterns of skin
lesions and subsurface skin
structures not normally
visible to the naked eye
4. PRINCIPLE
Trans illumination and magnification
Visibility of subsurface structures improved by LINKAGE fluids
Immersion oil
Olive oil
Mineral oil
Water
Antiseptic solution
Glycerin
Liquid paraffin
5. BASIC DESIGN
Achromatic lens -10
Inbuilt illuminating system-
Halogen lamps
Power supply
Inbuilt photography system
6. TYPES
Instruments without image capturing facility
Image capturing facility
Analytical capability
Videodermatoscope:
Polarised or non polarised video probe that
transmits images to monitor
12. WHAT IS DERMOSCOPY IS USED FOR?
EVALUATING PIGMENTED SKIN LESIONS
EVALUATING NONPIGMENTED SKIN LESIONS
ENTODERMOSCOPY
TRICHOSCOPY
ONYCHOSCOPY
13. COLOUR
• Epidermis appears white
• Melanin
• Upper epidermis- Black
• DEJ- Light to dark brown
• Papillary dermis- Slate blue
• Reticular dermis- Steel blue
14. • White shades- Regression
melanoma, halo nevus, lichenoid keratosis, scars
• Red shades- Increased vascularisation, bleeding
16. PRIMARY CRITERIA
• Pigmented network lines and hypo pigmented holes
• Histologically- the length of rete ridges and to
distribution of melanin within keratinocytes of
epidermal rete ridges
• Hypo pigmented holes- supra papillary plates
PIGMENT NETWORK
17. MELANOCYTIC NAEVUS
• PN slightly pigmented
• Light brown network
• Thin lines and fade gradually at periphery
• Holes are regular and narrow
21. PSEUDOPIGMENT NETWORK
• Homogenous pigmentation interrupted by
hypopigmented hair follicles and sweat gland openings
• Uniform & symmetric in colour and pattern – Benign
• Nonuniform & asymmetric – Lentigo maligna
22.
23. RADIAL STREAMING AND PSEUDOPODS
• Histologically- confluent junctional nests of atypical
melanocytes
• Linear extension of pigment at the periphery of
lesion
• Curved finger like projections, dark brown or black
25. PIGMENTED GLOBULES
• Round or oval, dark brown or black >1 mm
• Histologically -nests of pigmented melanocytes at
the junction in papillary dermis
• Milky red globules- nests of melanoma cells with
increased vascularity
26.
27. Cobble stone pattern- Benign melanocytic lesion
Dark or slate blue irregularly distributed- MM
28. SECONDARY CRITERIA
PIGMENTED DOTS
• Small round or irregularly shaped structures
• Black or dark brown
• Focal accumulations of free melanin or no. of highly
pigmented melanocytes in cornified layers of
epidermis
31. BLUE- WHITE VEIL
• Ground glass area of
pigmentation
• Blue grey to white in
colour
• Compact orthokeratosis
and hypergranulosis
• Confluent nests of
heavily pigmented
melanocytes in dermis
• Melanoma and Spitz nevi
37. NEGATIVE PIGMENT NETWORK
• Lighter serpiginous lines making up
cords and darker areas resembling
elongated tubular or curved globular
like structures
• Thin elongated hypo pigmented rete
ridges accompanied by the presence
of large nests of heavily pigmented
melanocytic cells at dermal papillae
• Highly specific for melanoma
38. CHRYSALIS STRUCTURES
• Thick, short, bright, whitish
linear structures
• Orthogonally oriented
• Changes in composition
and orientation of collagen
• Melanoma, Spitz nevi,
Dermatofibroma ,BCC
42. RED- BLACK LAGOONS
• Small, well defined,
round or oval areas
• Thrombi within the
vascular spaces of
papillary dermis
• Hemangioma and
angiokeratoma
43. MAPLE LEAF- LIKE PIGMENTATION
Heavily pigmented
basaloid cells
BCC
59. PIGMENTED BCC
Negative feature: Absence of
pigment network + At least one
Linear and arborizing telangiectasis
Leaf-like or structure less areas on
the periphery
Multiple blue gray nodule
Large blue gray ovoid nests
Focal ulceration
Spoke wheel areas
60. SEBORRHEIC KERATOSIS
• Multiple milia like cysts
• Comedo-like openings
• Hyperkeratosis/ fissures/
ridges
• Light brown finger like
structures
• Hairpin blood vessels
• Cerebriform apperance
63. ACTINIC KERATOSIS
• Pink/ red pseudo network& erythema surrounding the
hair follicle
• White to yellow surface scales
• Linear or wavy vessels surrounding the hair follicle
• Hair follicle openings filled with yellowish keratotic
plugs
64. SEBACEOUS HYPERPLASIA
• Central follicular opening
&surrounding yellow
nodule
• Vessels may extend to the
centre of lesion
• Never arborizing
76. COMMON WART
• Multiple densely packed
papillae with a central dot
or loop, surrounded by
whitish halo
• Small red to black dots
PLANTAR WART
• Prominent haemorrhage
within yellowish papilliform
surface
77. PLANE WART
Regularly distributed red dots, light brown to
yellow background
GENITAL WART
Mosaic pattern, finger like or knob
like pattern, nonspecific pattern
78. MOLLUSCUM CONTAGIOSUM
• Central pore or
umbilication
• White to yellow
amorphous structures
• Peripheral linear or
branching vessels (red
corona)
80. RARE SKIN INFECTIONS
TUNGIASIS
Nodule with a central targetoid brownish ring, which in turn
surrounds a central, black, pore.
CUTANEOUS LARVA MIGRANS
Translucent brownish structure less areas in a segmental
arrangement, corresponding to the body of the larva
81. MYCOSES
TINEA NIGRA
Reticulated pattern , consisting of superficial fine, wispy,
light-brown strands or 'pigmented spicules’
ONYCHOMYCISIS
White to yellow streaks and homogeneous areas in the
distal nail plate.
102. • Examine the nail plate from above as well as end-on
• Pigment in the top of the nail plate - proximal matrix
• Pigment at the bottom of the nail plate - distal matrix or
nail bed.
103. Melanocytic naevus of the nail apparatus is
characterised by:
Regular parallel lines
Brown background
Granular inclusions
105. NAIL MATRIX MELANOMA
• Longitudinal brown to black parallel lines with irregular
colouration, spacing, or thickness
• Disruption of parallelism
• Brown background
• Hutchinson sign: pigmentation of cuticle
• Nail plate fissuring or destruction
111. Benefits
• Dermoscopy increases the sensitivity for the diagnosis of
melanoma without decreasing the specificity
• Dermoscopy reduces the number of unnecessary
biopsies.
• Dermoscopy allows digital surveillance and monitoring of
in patients with multiple atypical nevi.
• Dermoscopy is useful in the diagnosis and differentiation
of nonmelanocytic benign and malignant tumors
112. Limitations
• The diagnostic accuracy of dermoscopy- experience in the
interpretation of dermoscopy .
• May fail to recognize melanomas that lack specific dermoscopic
criteria (featureless melanomas) .
• Dermoscopy alone cannot establish the diagnosis of malignancy;
histopathologic examination remains the gold standard.
