Neuromuscular Ultrasound Assessment of the Facial Nerve in Bell’s Palsy: A Narrative Review

Abstract

Facial palsy presents a diagnostic challenge, with most acute cases classified as idiopathic (Bell’s palsy). As a diagnosis of exclusion, it requires careful evaluation to rule out other treatable or serious causes. Conventional imaging modalities such as CT and MRI can identify underlying pathology; however, they are costly and not always readily available. High-resolution ultrasonography (HRUS) has emerged as a practical complementary tool, offering non-invasive, accessible, and radiation-free imaging that enables direct assessment of facial nerve morphology, pathological changes, and compressive lesions. This narrative review is evidence-based while also incorporating practical insights from recent clinical applications. It aims to provide clinicians with an accessible overview of HRUS in Bell’s palsy, with emphasis on sonographic techniques, procedural standards, characteristic findings, and their clinical implications for patient diagnosis and management.