Brachial Plexopathies: A Comprehensive Radiologic Method Integrating Ultrasound and MRI

Background: Brachial plexopathies comprise a diverse array of illnesses with multifactorial etiologies, including trauma, inflammation, neoplasia, and iatrogenic damage, frequently manifesting with nonspecific clinical symptoms. Precise and prompt imaging evaluation is essential for diagnosis, treatment planning, and monitoring. Objective: To equip radiologists with interpretative tools for a systematic assessment of the brachial plexus utilizing advanced imaging modalities, specifically ultrasound (US) and magnetic resonance imaging (MRI), while emphasizing techniques, indications, limitations, and critical radiologic signs for differential diagnosis. Imaging Techniques: This narrative review concentrates on US and MRI. High-frequency linear probes with multiplanar dynamic scans provide US visualization of trunks, cords, and terminal branches in superficial areas. Specialized MRI procedures (T1, T2, STIR, DWI, contrast-enhanced) provide comprehensive evaluation of spinal roots and deep tissues, differentiating preganglionic from postganglionic lesions. A combined US-MRI methodology can enhance diagnostic efficacy. Findings: Ultrasound is excellent for superficial and dynamic assessment, especially in post-traumatic and iatrogenic lesions, while MRI is the gold standard for deep structures and complex disorders. The integration of two modalities enhances lesion identification and treatment direction. Emerging methodologies further enhance diagnostic and prognostic capabilities. Conclusions: The synergistic application of US and MRI, emphasizing nerve injury patterns and muscle denervation indicators, facilitates precise and prompt diagnosis of brachial plexopathies. Standardizing imaging standards and incorporating modern techniques are essential for interdisciplinary, customized patient care.