What type of imaging should be ordered for a patient with forehead and jaw pain and vision issues lasting 2-3 months?

Imaging for Forehead and Jaw Pain with Vision Issues

MRI of both the brain and orbits with contrast is the optimal initial imaging study for a patient with forehead and jaw pain and vision issues lasting 2-3 months. 1

Rationale for MRI as First-Line Imaging

MRI provides superior soft-tissue resolution for detecting pathology affecting:

• The visual pathways
• Cranial nerves (particularly trigeminal and facial nerves)
• Orbital structures
• Brain parenchyma

The combination of symptoms (forehead pain, jaw pain, and vision issues) suggests potential involvement of:

• Trigeminal nerve (CN V) - responsible for facial sensation including forehead and jaw
• Visual pathways - accounting for the vision issues
• Possible orbital pathology

Key MRI Protocol Elements

• MRI orbits without and with contrast - for evaluating the globe, optic nerve, and orbital structures 2
• MRI brain without and with contrast - to assess for intracranial pathology 2
• Dedicated orbital sequences - necessary for proper evaluation of orbital structures 1
• Thin-slice sequences through the pituitary and suprasellar region - particularly important for visual pathway evaluation 1

Alternative Imaging Options

CT Considerations

• CT of the head/orbits with contrast may be considered if:
  • MRI is contraindicated (pacemaker, metal implants, claustrophobia)
  • MRI is unavailable
  • Trauma is suspected as part of the etiology 2
  • Bony abnormalities are suspected 2

When to Consider Additional Imaging

• If initial MRI shows concerning findings that require further characterization
• If symptoms worsen or change despite normal initial imaging
• If vascular pathology is suspected, MRA or CTA may be warranted 2

Clinical Considerations Affecting Imaging Choice

Age Considerations

• For patients >50 years with these symptoms, evaluation for giant cell arteritis (GCA) is critical
• Laboratory tests including ESR and CRP should be obtained alongside imaging 1
• Jaw claudication specifically raises concern for GCA with a positive likelihood ratio of 4.90 1

Duration of Symptoms

• The 2-3 month duration suggests a subacute or chronic process rather than an acute emergency
• This timeframe makes certain diagnoses like acute stroke less likely but doesn't exclude neoplasm, demyelination, or inflammatory conditions 2

Specific Diagnostic Considerations

• Trigeminal neuralgia or neuropathy - MRI is superior for evaluating the trigeminal nerve 2
• Orbital inflammatory conditions - MRI provides better soft tissue characterization 2
• Intracranial pathology extending to orbit - MRI with contrast is optimal 2

Common Pitfalls to Avoid

1. Ordering standard brain MRI without orbital sequences - may miss pathology specific to the orbit or optic nerve 1

2. Relying on CT alone - while faster and more available, CT can miss subtle lesions affecting the visual pathways and cranial nerves 1

3. Overlooking giant cell arteritis in older patients - can result in permanent visual loss if treatment is delayed 1

4. Failing to include contrast - reduces sensitivity for detecting inflammatory and neoplastic conditions 2

5. Not considering the pattern of visual field loss to guide specific imaging focus:

   • Bitemporal hemianopia suggests chiasmatic lesion
   • Homonymous hemianopia suggests post-chiasmatic lesion
   • Monocular visual loss suggests pre-chiasmatic lesion 1

By obtaining MRI of both the brain and orbits with contrast as the initial imaging study, you maximize the likelihood of identifying the underlying cause of this patient's symptoms while minimizing the need for additional imaging studies.