Conventional pattern analysis with morphological terminology has been shown to be very accurate. But it’s complicated, and takes a long time to learn.
Modified pattern analysis described by Harald Kittler uses descriptive terminology and is easy to learn, but sometimes clumsy.
Compare "yellow dot surrounded by skin-coloured circle surrounded by unfocussed curved thick red lines and sometimes angulated brown lines" (descriptive method) with "strawberry pattern" (morphological method).
People who have learned both methods tend to use a combination of morphological and descriptive terms.
Modified pattern recognition
Skin lesions are made up of basic dermatoscopic elements.
The elements group together to form patterns.
These terms describe pigment/melanin and blood/blood vessels.
The 3 most basic elements are:
Structureless zones (no lines or clods)
Other elements are:
Dots (smaller than clods)
Circles (joined-up lines)
Pseudopods (clod on the end of a line)
Colours in dermatoscopy:
Melanin: black, dark brown, light brown/tan, grey, blue from superficial epidermis to deep dermis
Keratin: white, yellow
Blood: reddish black, red, purple, blue
Arrangements of lines include:
Network / reticular pattern
Curved parallel lines
Structures can be:
A benign skin lesion has symmetrical structures and patterns
Its shape may or may not be symmetrical
It is made up of elements forming 1, 2 or 3 patterns
It usually has only 1 or 2 colours
A malignant skin lesion rarely has symmetrical structures or patterns
It includes ≥ 2 elements / patterns, usually ≥ 3
These are distributed irregularly
Often there are ≥ 5 colours
Destructive lesions can lose lines and clods
Grey and white structures often represent regression and/or scarring