The Dermoscopic technique
The observation of pigmented skin lesions and early recognition of melanoma
The dermoscopic exam allows the clinician to observe the skin pigmented structures through a conctact lens.
On the skin surface under investigation a drop of immersion oil, or wateris placed in order to remove the light reflection.
Each skin lesion can be observed using a manual lens, a hand held microscope, a stereomicroscope or a video-computerized microscopy system.
The power of magnification range from 6 to 40 fold, and can occasionally reach 100 fold.
The common dermoscope has a 10 fold power of magnification, which is good for a detailed observation of the lesion under investigation.
The liquid placed between the skin and the glass eliminates the annoying component of light reflected from the stratum corneum, allowing the clear visualization of the skin pigmented structures, of the dermo-epidermic junction and of the outer derm.
A waste semiology for the study of pigmented skin lesions patterns exists.
The technique enables the operator to assess, at the same time, the dimension and morphology of vases of the superficial capillary plexus, which is found to be altered in many pathological conditions.