dermatoscopy

Dermoscopy, also called dermatoscopy, is a noninvasive imaging technique that uses a handheld dermoscope to magnify and illuminate skin lesions, revealing subsurface structures not visible to the naked eye. By visualizing pigment networks, vascular patterns, and other features, dermoscopy assists in distinguishing benign from malignant lesions. It can be performed with non-polarized light in contact mode or with polarized light in non-contact mode, sometimes using a gel interface.

Equipment and technique: A dermoscope typically provides 10 to 20x magnification and a bright, uniform light source. Contact dermoscopy uses gel or oil to improve visualization and reduce surface reflections; non-contact, often with polarized light, minimizes skin contact. Many devices connect to cameras or smartphones for documentation and teledermatology.

Features and interpretation: Dermoscopy reveals patterns such as pigment networks, dots and globules, streaks, and blue-white veils, along with vascular structures and areas of regression. Pattern analysis and checklists guide assessment, though final diagnosis usually requires histopathology when indicated. Experience influences accuracy.

Applications and impact: Dermoscopy is an important tool in dermatology for screening pigmented lesions, guiding biopsies, and monitoring lesions over time. When performed by trained clinicians, it can reduce unnecessary excisions and improve diagnostic confidence.

Limitations and training: Adequate training is required to interpret dermoscopic patterns reliably. Limitations include variable quality of images, overlap between benign and malignant patterns, and reduced utility in inflamed or crusted lesions. It complements clinical examination and history rather than replacing biopsy.

History: Modern dermoscopy gained widespread use in the late 20th century with the development of polarized and non-polarized devices, advancing noninvasive assessment of skin tumors.