LANDMARKS IN DERMOSCOPY | Series introduction

From oil and glass to polarized light: eight milestones that shaped dermoscopy

Why is this paper important?
Modern dermoscopy did not emerge from a single invention. In this historical editorial, Ashfaq Marghoob traces eight milestones that transformed the examination of subsurface skin structures from an optical curiosity into an essential clinical technique.

The eight milestones

  1. Paul Gerson Unna demonstrated that oil and a glass plate could reduce surface reflection and make the skin more transparent.

  2. Otfried Müller and Carl Zeiss combined magnification with illumination to examine cutaneous capillaries.

  3. Johann Saphier introduced the term dermatoscopy and correlated visible structures with histopathology.

  4. Rona MacKie brought surface microscopy into the preoperative assessment of pigmented lesions.

  5. Pehamberger, Steiner and Wolff established pattern analysis as a systematic method for interpreting pigmented lesions.

  6. Portable handheld dermatoscopes made the technique practical for routine clinical use.

  7. Cross-polarized dermoscopy enabled examination without direct skin contact or immersion fluid.

  8. The International Dermoscopy Society helped standardise terminology, education and international collaboration.

Why does this matter today?
Many concepts we now take for granted—optical transparency, clinicopathological correlation, pattern recognition, portability, polarized light and shared terminology—represent distinct historical advances. Understanding this lineage helps explain why dermoscopy is both an imaging technology and an interpretative clinical discipline.

Important limitation
This is a single-author editorial narrative organised around eight selected milestones. It is not a systematic historical review or a diagnostic-accuracy study. It provides no patient cohort, comparator, reference standard or clinical-outcome data. The selection and relative importance of the milestones therefore reflect an expert historical perspective rather than a formally validated ranking.

My take
This article provides an excellent roadmap for a “Landmarks in Dermoscopy” series. Each milestone should now be revisited through its original publication: what was genuinely new, what changed practice and which ideas remain relevant today.

What do you think?

Which development most transformed everyday dermoscopy?

  • Pattern analysis

  • The handheld dermatoscope

  • Cross-polarized imaging

  • International consensus and education


Reference
Marghoob AA. A Window Beneath the Skin: The History of Dermoscopy from Curiosity to Clinical Cornerstone. Dermatol Pract Concept. 2026;16(1):7121. Published January 2026.
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