dermoscopy

Dermoscopy, also known as dermatoscopy, is a noninvasive skin imaging technique that allows in vivo visualization of subsurface skin structures by using a handheld dermatoscope. By reducing surface glare and enhancing contrast between light and pigment, it improves diagnostic accuracy for pigmented lesions and assists clinicians in distinguishing benign from malignant findings, thereby guiding management alongside standard clinical examination.

Modern dermoscopy employs either non-polarized light with direct contact using immersion fluid or polarized light, which can be used with or without contact. Non-polarized dermoscopy tends to reveal superficial architectural features, while polarized illumination can reveal deeper structures such as vascular patterns. Magnification is typically around 10 times, though higher magnification devices exist.

Applications include evaluation of pigmented lesions for melanoma risk, guiding biopsy decisions, and monitoring changes over time. Dermoscopy is also used in the assessment of nonpigmented skin tumors and in some inflammatory dermatoses, as well as in vascular patterns. Interpretation relies on standardized dermoscopic criteria and patterns, such as pigment network, streaks, dots and globules, blue-white veil, negative networks, and special structures, integrated within diagnostic algorithms to estimate likelihood of malignancy.

Training and experience influence accuracy, and dermoscopy is not infallible. Limitations include variability among examiners, potential artifacts from contact fluids, and the possibility of false negatives in amelanotic or subtle lesions. Histopathology remains the definitive diagnosis when cancer is suspected. Dermoscopy is a widely used adjunct in dermatology and primary care, with ongoing advances including digital imaging and teledermoscopy.