The role of various immersion liquids at digital dermoscopy in structural analysis

Background: Dermoscopy is a useful method that allows dermal and epidermal structures to be easily analysed non-invasively.
Aim: In this study, immersion oil, which is widely used in dermoscopy, and ultrasound gel, which is less preferred, are evaluated comparatively in terms of displaying structural parameters and number of air bubbles in the image.
Methods: A total of 71 nevomelanocytic or non-melanocytic pigmented lesions were taken up for this study. Structural characteristics of the obtained images were assessed by an experienced observer who scored the images in terms of color, pigment network, globule, vascular structure, number of air bubbles and other pigmentation parameters.
Results: In the images obtained through immersion oil or ultrasound gel from all of the lesions, no statistical difference was found between the average values of air bubbles and in the evaluation of structural components (t=1.09, P=0.2). In the identification of pigment network in melanocytic lesions, immersion oil was observed to be more appropriate than ultrasound gel (t=0.01, P=0.02).
Conclusions: Ultrasound gel may be preferred in the assessment of mucosa and nail bed lesions. Ultrasound gel is a good alternative compared to immersion oil in pigmented skin lesions as it is cheap and easily removable.