Intraoral Ultra-High Frequency Ultrasound study of oral lichen planus: A pictorial review

Background: Ultra-High Frequency Ultrasound (UHFUS) is a recently introduced diagnostic technique involving the use of higher frequencies compared to conventional ultrasound. Among the several fields of application, intraoral usage of UHFUS appears still limited. We report the intraoral evaluation of Oral Lichen Planus (OLP) by means of UHFUS and describe typical UHFUS aspect of different forms of presentation of OLP. Materials and Methods: Patients with clinical and histological diagnosis of OLP were enrolled in the study. OLP lesions were evaluated by means of intraoral UHFUS performed at 70 MHz, using B-mode and C-mode, in order to characterize the echostructure of each form of presentation. Results: Fifty patients in total were enrolled, and UHFUS features were described for different OLP forms. All the lesions showed a thick, hypoechoic superficial layer in the mucosal stratum, suggesting that such UHFUS alteration can be pathognomonic of OLP. Conclusion: Ultra-High Frequency Ultrasound was able to differentiate superficial alterations of the oral mucosa, giving insight on possible applications of UHFUS in the study of OLP beyond clinical and histological investigations. Due to a limited study sample, we cannot draw firm conclusions. However, it is reasonable to think that UHFUS evaluation of OLP may provide useful information to the clinician