feature rich melanoma
To contrast with the last few examples of slightly odd looking but harmless lesions, here is a proven melanoma. It looks very wrong on naked eye inspection due to asymmetry, highly irregular borders, mixed colour and darkness.
Dermoscopy reveals a wealth of additional features which take the level of diagnostic confidence from highly probable to beyond doubt. Features include irregular dots and globules, multiple colours including red, white and grey (which are almost always bad in a mole, especially in combination), abnormal network, radial streaming and blue grey veil. A thin (0.5mm) lesion at excision, so an excellent prognosis.
PS if you magnify this image up (a left click or 2 will do this), the irregular scattered dots in particular become much more visible. There are also some linear irregular vessels in the red portion and maybe some slightly out of focus pseudopods around 10 o’clock.
A dermoscopy sceptic might smile at this and say ‘you don’t need a dermoscope to diagnose that’. Fair enough, but they are not all as obvious as this and while the dermoscopy here raises the level of certainty which was already over the bar (on other words, this lesion should be excised on visual alone anyway) in other cases the increased evidence from dermoscopy will take a ‘maybe OK’ lesion over the bar and lead to excision. Also, very often dermoscopy will enable a questionable lesion to be safely graded as harmless. Anyway, do have a look at the specific features.
AS I said before, although all these images are and remain my copyright, I have no objection to clinicians saving a copy for private study and using, with acknowledgement, for any honest educational use such as small group teaching. Pro bono.