Is Optical Coherence Tomography (OCT) indicated for empty sella suggesting high Intracranial Pressure (ICP)?

OCT is Not Indicated for Empty Sella Suggesting High ICP

Optical Coherence Tomography (OCT) is not indicated as a primary diagnostic tool for empty sella suggesting high intracranial pressure (ICP). MRI of the head and orbits is the most useful imaging modality for evaluating suspected elevated ICP, including cases where empty sella is present 1.

Diagnostic Approach for Empty Sella and Suspected High ICP

Primary Imaging Modality

• MRI of the head and orbits is the preferred diagnostic imaging modality for evaluation of the pituitary and sellar regions, including empty sella 1
• MRI can effectively characterize empty sella even without IV contrast 1
• MRI provides higher resolution of intracranial and intraorbital structures compared to CT, making it more useful for detecting signs of elevated ICP 1

Key Neuroimaging Findings in High ICP

• Empty sella or partially empty sella is a typical neuroimaging feature found in raised intracranial pressure 1
• Other neuroimaging findings suggestive of high ICP that are best assessed with MRI include:
  • Posterior globe flattening (56% sensitivity and 100% specificity) 1
  • Intraocular protrusion of the optic nerve (40% sensitivity and 100% specificity) 1
  • Horizontal tortuosity of the optic nerve (68% sensitivity and 83% specificity) 1
  • Enlarged optic nerve sheath compared to control groups 1
  • Flattened posterior globe/sclera 1

Clinical Context of Empty Sella

• Empty sella is typically an incidental finding on imaging studies performed for unrelated reasons 2
• Empty sella can reflect chronically elevated ICP, particularly in idiopathic intracranial hypertension (IIH) 3
• The significance of empty sella can be determined using a combination of clinical and imaging findings 3
• Empty sella has been observed in patients with lateral sinus stenosis presenting with isolated pulsatile tinnitus without signs of intracranial hypertension 4

Clinical Evaluation When Empty Sella is Found

Key Symptoms to Assess

• Headache (present in nearly 90% of patients with IIH) 5
• Visual disturbances, including transient visual obscurations 5
• Pulsatile tinnitus 5
• Diplopia, typically horizontal, often due to sixth nerve palsy 5
• Papilledema (a key diagnostic finding in pseudotumor cerebri syndrome) 1

Important Clinical Distinctions

• Pseudotumor cerebri predominantly affects overweight females of childbearing age 5
• In the absence of papilledema and sixth nerve palsy, diagnosis of pseudotumor cerebri can be suggested on neuroimaging based on findings including empty sella 1
• Empty sella is found in both patients with IIH and those with symptomatic lateral sinus stenosis 4

Management Considerations

When Further Evaluation is Needed

• Visual changes or papilledema in patients with empty sella should prompt further evaluation 2
• Signs of increased intracranial pressure, including headache, pulsatile tinnitus, or diplopia, should be evaluated further 2
• Basic hormonal screening may be necessary to rule out central hypothyroidism and assess adrenal axis in patients with empty sella 2

Treatment Approach

• Where there is evidence of declining visual function, the acute management to preserve vision is surgical 1
• Weight loss has been shown to be effective in putting IIH into remission in some patients 1
• After successful treatment of IIH, the appearance of the sellar contents may normalize 6

Common Pitfalls to Avoid

• Attributing unrelated symptoms directly to incidental empty sella findings without considering more common causes 2
• Ordering unnecessary urgent tests that won't change immediate management 2
• Failing to recognize when empty sella might be part of a more significant condition, such as pseudotumor cerebri 2

In conclusion, while empty sella may suggest high ICP, OCT is not indicated as the primary diagnostic tool. MRI remains the gold standard imaging modality for evaluating empty sella and other signs of elevated ICP.