MRI of Brain and Spine is the Next Step
This patient requires urgent MRI of the brain and spine to evaluate for demyelinating disease, particularly multiple sclerosis, given the recurrent neurological episodes with focal findings (dysmetria, hypertonicity) and slurred speech lasting hours. 1
Clinical Reasoning
This 39-year-old woman presents with a critical constellation of features that mandate neuroimaging:
- Recurrent episodes of neurological dysfunction (current episode at 6 hours, previous episode resolved in <12 hours) 1
- Focal neurological signs including dysmetria (cerebellar dysfunction) and leg hypertonicity (upper motor neuron involvement) 1
- Dysarthria (slurred speech) as a focal neurologic symptom 1
- Young adult female in the typical demographic for multiple sclerosis 1
The American Academy of Otolaryngology-Head and Neck Surgery guidelines specifically identify "focal neurologic symptoms or signs, such as headache, confusion, diplopia, dysarthria, focal weakness, focal numbness, ataxia" as indicators of serious underlying causes requiring immediate investigation. 1
Why MRI Brain and Spine?
MRI is the diagnostic modality of choice because:
- Multiple sclerosis characteristically shows white matter changes most easily visualized on FLAIR sequences 1
- The combination of brain and spine imaging is essential because MS lesions can occur in either location, and spinal cord involvement may explain the leg hypertonicity 1
- MRI can identify structural lesions causing recurrent neurological deficits 1
- The recurrent, self-limited nature of symptoms with focal findings strongly suggests demyelinating disease requiring visualization of CNS lesions 1
Why Not the Other Options?
CSF oligoclonal bands are premature at this stage—while they support MS diagnosis, they should follow MRI findings, not precede them. MRI provides the structural diagnosis first. 1
EEG would be appropriate if seizures were suspected, but this patient has persistent focal deficits without the episodic nature, loss of consciousness, or post-ictal features typical of seizures. 1
No further testing is inappropriate given the presence of focal neurological signs and recurrent episodes—these are red flags for serious underlying pathology that could lead to permanent disability if untreated. 1
Common Pitfalls
- Do not dismiss recurrent neurological symptoms in young adults as functional or benign without imaging—early MS diagnosis and treatment significantly impacts long-term disability 1
- Do not wait for symptoms to worsen before obtaining imaging—the guidelines emphasize that focal neurologic findings warrant immediate visualization regardless of symptom duration 1
- Do not assume normal vital signs exclude serious pathology—demyelinating diseases and structural CNS lesions typically present with normal vital signs 1