Parotid Gland Magnetic Resonance Elastography Feasibility Study: Clinical Diagnostic Potential and Future...

Background/Objectives: Magnetic resonance elastography (MRE) is a noninvasive imaging technique that quantitatively characterizes tissue mechanical properties. This study aimed to establish and validate a feasible parotid MRE protocol using 3T MRI, with potential relevance for oral and maxillofacial surgery (OMFS) and otorhinolaryngology practice. Methods: This study included 21 healthy volunteers (18 women, 3 men; mean age, 49 years) examined between January and May 2024. MRE was performed using a 3.0 Tesla MRI system (Discovery MR750w, GE Healthcare, Waukesha, WI, USA) with a passive driver positioned over the parotid gland in a 16-channel head/neck coil. Two radiologists independently analyzed axial magnitude images drawing regions of interest (ROIs) encompassing the entire gland while excluding intraparotid lymph nodes and vascular structures. Mean and maximum stiffness values (kPa) were recorded for each gland. Interobserver agreement was assessed using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Results: Mean stiffness was 1.209 ± 0.240 kPa (Radiologist 1) and 1.146 ± 0.233 kPa (Radiologist 2); maximum stiffness was 1.595 ± 0.532 kPa and 1.563 ± 0.528 kPa, respectively. ICCs were 0.638 for mean stiffness and 0.918 for maximum stiffness, indicating moderate-to-excellent agreement. Conclusions: MRE is a technically feasible and reproducible method for evaluating parotid stiffness using standard imaging infrastructure. This feasibility study in healthy volunteers provides normative stiffness values for the parotid gland and supports MRE as a potential tool for "radiological palpation" to aid in the differentiation of salivary gland lesions and post-treatment assessment in OMFS and otorhinolaryngology practice.