Abstract
Background Scalp lesions encompass a diverse array of dermatological conditions, ranging from benign and transient issues to chronic, relapsing, or potentially scarring diseases. Accurate and timely diagnosis is crucial for appropriate management and prognostication. Traditional clinical examination, though essential, may not always suffice in differentiating between closely related scalp conditions. In this context, dermoscopy has emerged as a vital, non-invasive diagnostic adjunct. It provides enhanced visualization of subsurface skin and hair structures, aiding in pattern recognition and improving diagnostic accuracy for a variety of scalp disorders. Aim To evaluate and classify various scalp lesions based on clinical and trichoscopic features using a dermoscope. Methods A cross-sectional observational study was conducted over 20 months (August 2022 to March 2024) at a tertiary care centre. A total of 200 patients were enrolled. All patients underwent detailed clinical evaluation followed by trichoscopic examination using the DermLite DL4 dermoscope (10× magnification, polarized mode). Trichoscopic features were systematically recorded and correlated with clinical diagnoses and were grouped into major diagnostic categories and analyzed to identify characteristic patterns. Results A total of 200 were included in the study, with the highest prevalence observed in the 19- to 30-year age group. The most commonly reported symptoms were itching (64.5%) and hair loss (55%). The most frequent diagnostic categories were papulosquamous disorders (39%), alopecia (31.5%), infections and infestations (16%), autoimmune conditions (8.5%), and miscellaneous disorders (5%). Psoriasis (19%) and seborrheic dermatitis (17.5%) were the most prevalent individual diagnoses, while alopecia areata accounted for 12.5% of the cases. Trichoscopic examination in psoriasis patients revealed red dots as the most common feature (92.3%), followed by silvery-white scales (84.6%), nonspecific red areas (69.2%), and the "hidden hair" sign (61.5%). Abnormal vascular patterns (25.6%), yellow dots (20.5%), and perifollicular scaling (12.8%) were less frequent. In seborrheic dermatitis, the predominant trichoscopic feature was perifollicular scaling (65.7%), followed by atypical vascular patterns (42.8%, n=15), yellow dots and interfollicular scaling (40%) each, the "hidden hair" sign (37.1%), nonspecific red areas (34.2%), and red dots (8.5%). For alopecia areata, trichoscopic findings included black dots (84%), yellow dots (72%), vellus hairs (60%), broken hair shafts (44%), and the exclamation mark sign (28%). Conclusion Trichoscopy proved to be an invaluable, non-invasive diagnostic tool in the assessment of scalp lesions. It allowed rapid visualization of hallmark features, improving diagnostic accuracy and often reducing the need for invasive procedures such as scalp biopsies. The study demonstrates that distinct trichoscopic features serve as reliable markers for differentiating papulosquamous disorders and various forms of alopecia. Additionally, trichoscopy was effective in distinguishing between scarring and non-scarring alopecia, thereby enhancing diagnostic precision. Incorporating dermoscopy into routine dermatological evaluation improves diagnostic confidence and enables earlier, targeted interventions. Given its ease of use, reproducibility, and diagnostic value, trichoscopy should be considered an essential component in the evaluation of scalp dermatoses.