What type of Magnetic Resonance Imaging (MRI) is best for assessing headache with visual disturbance in a child?

MRI Head and Orbits with and without IV Contrast

For a child presenting with headache and visual disturbance, MRI of the head and orbits with and without IV contrast is the imaging modality of choice. 1, 2

Why This Specific Protocol

The combination of head and orbits imaging is essential because visual disturbances in children with headache can originate from multiple locations along the visual pathway:

• The orbits (including optic nerves) require dedicated imaging with fat-suppressed sequences to detect optic nerve pathology 1
• The brain parenchyma must be evaluated for lesions affecting the thalamus, optic radiations, or occipital lobes 1
• T1-weighted post-contrast images with fat suppression identify abnormal optic nerve enhancement in 95% of optic neuritis cases 1, 2
• Coronal fat-saturated T2-weighted sequences are specifically recommended to evaluate for dilatation of the optic nerve sheaths 1

Why Contrast is Critical

Contrast administration is non-negotiable in this clinical scenario:

• Detects meningeal infiltration and isodense tumors that would be missed on non-contrast imaging 1
• Identifies abnormal meningeal enhancement suggesting inflammatory or infiltrative processes 1
• Reveals enhancing lesions in demyelinating disorders, which are common causes of vision loss with headache in children 1, 2
• Differentiates active inflammatory lesions from chronic changes 1

Superiority Over Other Modalities

MRI is definitively superior to CT for this presentation:

• MRI reveals more details of intracranial structures without radiation exposure 1
• MRI has superior sensitivity for detecting early stroke changes, which can present with headache and visual symptoms 1
• MRI better evaluates for structural lesions, tumors, and parenchymal abnormalities 1
• CT may miss subtle posterior fossa lesions and optic pathway abnormalities that MRI readily detects 3

Critical Differential Diagnoses to Exclude

This imaging protocol addresses the most serious causes of headache with visual disturbance in children:

• Optic neuritis (most common cause of acute vision loss in children, often associated with headache) 1, 2
• Brain tumors affecting the visual pathway (94% of children with brain tumors have abnormal neurological findings at diagnosis) 4
• Acute infarct or hemorrhage involving the thalamus, optic radiations, or occipital lobes 1, 2
• Demyelinating disorders (multiple sclerosis, neuromyelitis optica spectrum disorders) 1, 2
• Increased intracranial pressure with papilledema 1

Additional Imaging Considerations

In specific clinical contexts, supplementary imaging may be warranted:

• Add MRV if pseudotumor cerebri (idiopathic intracranial hypertension) is suspected based on papilledema or other signs of venous sinus abnormalities 1
• Consider MRA if sickle cell disease is present or if arterial stroke is suspected 1
• MRI complete spine may be added if demyelinating disorder is suspected to assess disease burden 1, 2

Common Pitfalls to Avoid

Do not order MRI head alone without orbits—this misses intraorbital optic nerve pathology that frequently causes vision loss in children 1, 2

Do not order non-contrast MRI only—contrast is essential for detecting optic neuritis, meningeal disease, and enhancing tumors 1, 2

Do not assume migraine with visual aura without imaging when focal neurological findings are present—abnormal examination findings dramatically increase the likelihood of structural pathology 4

Be aware that meningeal enhancement can occur after lumbar puncture and should not be confused with pathology 1