What is the workup for empty sella syndrome?

Workup for Empty Sella Syndrome

MRI with high-resolution pituitary protocol is the gold standard imaging modality for diagnosing empty sella syndrome, followed by comprehensive hormonal assessment to detect potential pituitary dysfunction that occurs in up to 40% of cases. 1, 2

Diagnostic Imaging

Primary Imaging

• MRI of the sella:
  • High-resolution pituitary protocol is preferred
  • Can characterize empty sella even without IV contrast
  • Visualizes pituitary gland flattening against sellar floor
  • Assesses pituitary stalk and optic chiasm
  • Detects herniation of subarachnoid space into sella turcica 1, 2

Alternative Imaging (if MRI contraindicated)

• CT scan of the sella:
  • Less sensitive than MRI for pituitary abnormalities
  • Useful for evaluating bony structures of the sella
  • May show sellar enlargement or bony erosion 1

Hormonal Assessment

Empty sella requires comprehensive hormonal evaluation as up to 40% of patients may have at least one hormone deficiency 2. The following should be assessed:

• Anterior pituitary function:

  • Growth hormone (GH) and IGF-1 levels
  • Thyroid function tests (TSH, free T4)
  • Adrenal function (morning cortisol, ACTH)
  • Gonadal hormones (FSH, LH, testosterone in men, estradiol in women)
  • Prolactin levels 2, 3

• Dynamic testing (if baseline results are abnormal):

  • Insulin tolerance test (ITT) for GH and cortisol reserve
  • TRH stimulation test
  • LHRH/GnRH stimulation test 4

Clinical Evaluation

• Visual field testing: To assess for potential compression of optic chiasm
• Blood pressure measurement: Hypertension is a common finding 5
• Assessment for symptoms of hormone deficiencies:
  • Fatigue, weakness
  • Headaches
  • Menstrual irregularities in women
  • Sexual dysfunction 6, 7

Differential Diagnosis

• Primary vs. Secondary Empty Sella:
  • Review history for previous pituitary surgery, radiation therapy, or medical treatment
  • Assess for history of pituitary apoplexy, trauma, or autoimmune disease 7

Common Pitfalls to Avoid

1. Assuming empty sella is always a benign incidental finding - Up to 30% of patients may have clinically significant hypopituitarism requiring treatment 2

2. Missing primary hypothyroidism - While central hypothyroidism is more common, primary hypothyroidism can coexist with empty sella syndrome and requires different management 4

3. Failure to distinguish between primary and secondary empty sella - Secondary empty sella requires management of the underlying cause 2, 7

4. Overlooking asymptomatic hormonal deficiencies - Some patients may have biochemical abnormalities without obvious clinical manifestations 5

By following this systematic approach to the workup of empty sella syndrome, clinicians can ensure appropriate diagnosis and management of this condition that extends beyond being a mere incidental finding.