17. Serial peripheral nerve ultrasound in Guillain–Barré syndrome

•Serial nerve ultrasound studies demonstrate gradual improvement in nerve cross-sectional area in Guillain–Barré syndrome.•The changes become significant after 12weeks of disease onset when patients are in the recovery phase.•In the acute phase, nerve ultrasound may not be able to differentiate between axonal and demyelinating subtypes based on nerve cross-sectional areas.