Criteria to be assessed by dermoscopic examination

The dermoscopic diagnosis of pigmented skin lesions is based on various analytic approaches or algorithms that have been set forth in the last few years, namely, pattern analysis, ABCD rule and seven-point checklist to quote but a few. The common denominator of all these diagnostic methods are particular dermoscopic features or, better, dermoscopic criteria that represent the backbone for the morphologic diagnosis of pigmented skin lesions.

In the second step of this course several examples of all relevant dermoscopic criteria and their underlying histopathologic structures will be demonstrated in order to teach students of the subject the letters of the dermoscopic alphabet. These letters, at least in our estimation, represent a ‘conditio sine qua non’ for learning and understanding dermoscopy. Also, knowledge of dermoscopic criteria yields a basic source for further studies in this field and may help communicate the method of dermoscopy to the clinical dermatologist. In order to achieve this goal we will focus on already well established criteria while refining some not clearly elaborated ones. Further, some new dermocopic criteria such as exophytic papillary structures and central white patches are introduced.

By assessing dermoscopic images, basically two common groups, namely, global and local features, can be recognized. They will be displayed systematically in the following pages. 

  • First, we will focus on nine morphologically rather distinctive global features that allow a quick, albeit only preliminary categorization of a given pigmented skin lesion prior to more detailed assessment.

  • Second, we will turn to the various local features representing the letters of the dermoscopic alphabet.

References

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