Introduction: In Guillain-Barré Syndrome (GBS), an increased cross-sectional area (CSA) of the vagus nerve (VN) has been described as a diagnostic tool and as an indicator of autonomic dysfunction.
Methods and Objectives: With the presentation of a GBS case, we aim to describe the technique for assessing the CSA of the VN using ultrasound (US).
Results: The evaluation of the VN CSA by US is a diagnostic technique with several advantages for clinicians. CSA values greater than 3 mm² are associated with the demyelinating variant of GBS and a higher likelihood of autonomic dysfunction.
Conclusion: The assessment of VN CSA by US is a useful tool in the diagnostic approach to patients with suspected GBS.
