Optical Coherence Tomography in Nail Research and Diagnosis

Optical coherence tomography (OCT) is a noninvasive and in vivo real-time diagnostic approach that allows for the visualization of skin architecture and cutaneous blood vessels. OCT provides a quick and useful diagnostic imaging technique for a number of nail disorders including psoriasis, glomus tumors, and subungual myxoid cysts and is a valuable addition to other noninvasive imaging tools such as dermoscopy and high-frequency ultrasound

Vascular Tests for Dermatologists

Dermatologists encounter patients with a variety of lower extremity ulcers including those related to venous insufficiency and peripheral arterial disease. Vascular studies, including ankle brachial pressure index, toe pressure, toe brachial index, Doppler arterial waveform, Duplex ultrasonography, and angiography, play an essential role in the prevention, diagnosis, and management of vascular diseases. In fact, dermatologists are often the first medical providers to see patients with complex vascular conditions. Knowledge of the appropriate indications, interpretations, limitations, and advantages of the various vascular studies is critical to the successful and swift management of each patient presenting with a lower extremity ulcer. This study reviews the most commonly ordered arterial and venous studies and discusses the appropriate indications and interpretation of these studies

Evaluation of positive patch test reactions using optical coherence tomography: A pilot study

Patch testing is the gold standard for evaluating allergic contact dermatitis (ACD), yet current interpretation methods are limited by their subjectivity and possible variability between observers. Optical coherence tomography (OCT) imaging enables noninvasive in vivo skin visualization and holds promise as an objective method of patch test interpretation. To evaluate the micromorphological changes of patch test reactions and identify objective, quantitative OCT markers that correlate with clinically graded patch test reactions. A total of 25 patch test reactions (7 grade-0, 4 grade-1+, 14 grade-2+) from 7 patients underwent OCT evaluation. Increased epidermal thickness and density was qualitatively observed in grade 1+ and grade 2+ allergic reactions while well-demarcated, signal-free cavities were observed in all grade 2+ reactions. Attenuation coefficients significantly increased across the three reaction grades (2.58 ± 0.092, 2.96 ± 0.121, 3.05 ± 0.065; P < 0.01). Cutaneous blood flow at 0.35 mm monotonically increased with reaction grade severity and blood measurements significantly differed across the three reaction grades (0.053 ± 0.011 mm/s, 0.078 ± 0.015 mm/s, and 0.121 ± 0.008 mm/s; P < 0.01). Attenuation coefficient and cutaneous blood flow at 0.35 mm correlate with clinically graded patch test reactions and hold promise as objective, quantitative markers. OCT may help dermatologists differentiate clinical scoring of allergic reactions in patch test and thereby improve their diagnostic accuracy and interpretation of patch test reactions