A 4-year-old boy is evaluated in the pediatric clinic due to a 4-week history of increasing unsteadiness and frequent falls. His parents note that he was previously running and climbing without difficulty but has recently begun walking with his feet wide apart. He also complains of head pain upon waking in the mornings, accompanied by two recent episodes of non-bilious emesis. His developmental history was previously normal. On physical examination, his temperature is 37.0°C (98.6°F), blood pressure is 115/75 mm Hg, pulse is 80/min, and respirations are 20/min. Fundoscopic examination reveals blurred optic disc margins bilaterally. He exhibits truncal ataxia and nystagmus on lateral gaze. Which of the following is the most appropriate next step in the management of this patient?
- AReassurance and continued observation of gross motor milestones
- BLumbar puncture with measurement of opening pressure
- Magnetic resonance imaging of the brainCevap
- DAdministration of oral sumatriptan for migraine management
- EElectroencephalography to evaluate for subclinical seizures