What is the next step in management for a patient with fullness in the sella (sella turcica) of the brain on a computed tomography (CT) scan?

Management of Fullness in the Sella on CT Scan

The next step is to obtain an MRI of the sella using high-resolution pituitary protocols, which is the gold standard for evaluating sellar pathology and far superior to CT for characterizing lesions in this region. 1, 2

Why MRI is Essential

CT is fundamentally inadequate for evaluating sellar pathology compared to MRI. Even with optimized technique, CT is insensitive for detecting pituitary lesions, particularly microadenomas and subtle abnormalities 1. The key advantages of MRI include:

• Superior tissue characterization - MRI directly visualizes the pituitary gland, infundibulum, optic chiasm, and vascular structures with high resolution 1
• Detection of microadenomas - Small hormone-secreting tumors (<10 mm) are reliably depicted, especially with contrast enhancement showing them as hypoenhancing lesions 1
• Characterization of empty sella - MRI can confirm empty sella syndrome even without IV contrast 1, 2
• Assessment of critical structures - Evaluates optic chiasm compression, cavernous sinus invasion, and suprasellar extension 1

Clinical Assessment While Awaiting MRI

Symptoms Suggesting Elevated Intracranial Pressure

Evaluate for these specific red flags that indicate urgent pathology:

• Headache patterns - Headaches awakening the patient from sleep, worsened by Valsalva maneuver, or rapidly increasing in frequency 2, 3
• Visual symptoms - Transient visual obscurations, diplopia (particularly horizontal from sixth nerve palsy), or any visual field defects 2
• Papilledema - This is the key diagnostic finding in pseudotumor cerebri syndrome 2
• Pulsatile tinnitus - Common in idiopathic intracranial hypertension 2

Symptoms Suggesting Pituitary Dysfunction

Screen for hormonal deficiencies:

• Hypothyroidism - Fatigue, cold intolerance 3
• Hypogonadism - Sexual dysfunction, loss of libido, amenorrhea in premenopausal females 1
• Hyperprolactinemia - Galactorrhea, amenorrhea 1
• Growth hormone excess - Acromegaly features 1

MRI Protocol Specifications

The MRI must include:

• High-resolution pituitary sequences with thin-section acquisition and focused field-of-view targeted for sellar and parasellar assessment 1
• Pre- and post-contrast T1-weighted sequences to increase conspicuity of adenomas 1, 4
• Coronal fat-saturated T2-weighted sequences to evaluate optic nerve sheaths if elevated ICP is suspected 2
• MR venography (MRV) if pseudotumor cerebri is suspected, to evaluate for venous outflow obstruction 2

Hormonal Screening

Obtain basic hormonal screening regardless of symptoms, as approximately 30% of patients with empty sella demonstrate hypopituitarism upon testing 2, 3:

• Thyroid function - TSH, free T4 (deficiencies seen in up to 48% of cases) 3
• Adrenal axis - Morning cortisol and ACTH 3
• Sex hormones - Testosterone in males, estradiol/FSH/LH in females 3
• Prolactin - Elevated in approximately 28% of cases 3
• Growth hormone/IGF-1 if acromegaly suspected 4

When to Expedite Evaluation

Urgent ophthalmology referral and expedited MRI are indicated if:

• Visual field defects or declining visual acuity are present (visual recovery is unlikely after the first post-operative month) 4
• Papilledema is identified on fundoscopic examination 2
• Symptoms suggest acute pituitary apoplexy (sudden severe headache, visual loss, altered mental status) 1

Common Pitfalls to Avoid

• Do not rely on CT alone - CT frequently misses microadenomas and cannot adequately characterize cystic lesions or soft tissue invasion 1
• Do not assume normal exam excludes pathology - Any abnormal neurological finding significantly increases likelihood of clinically significant intracranial pathology 2
• Do not attribute headaches directly to empty sella without considering more common headache etiologies and ruling out elevated ICP 3
• Do not skip hormonal screening even in asymptomatic patients, as subclinical deficiencies are common 3

Subsequent Management Based on MRI Findings

If Pituitary Adenoma Identified

• Endocrinology referral for all cases 3
• Neurosurgery referral for macroadenomas or symptomatic microadenomas 4
• Medical management with dopamine agonists for prolactinomas 1

If Empty Sella Confirmed

• Endocrinology referral if hormonal abnormalities detected 3
• Consider lumbar puncture if elevated ICP suspected (opening pressure >250 mm H₂O confirms idiopathic intracranial hypertension) 2

If Elevated ICP Signs Present

• Lumbar puncture with opening pressure measurement 2
• Weight loss counseling if appropriate (effective in putting IIH into remission) 2
• Neurosurgery consultation if medical therapy fails or visual function declining 2