Diagnostic Imaging and Testing
The ability to create images of the pituitary gland, which is located deep inside the skull, has led to tremendous advances in diagnosing and treating pituitary disorders.
Today, magnetic resonance imaging (MRI) scans are the state-of-the-art technique for diagnosing and following pituitary disorders. These can be used to explore possible causes of headaches, vision problems or hormone abnormalities. The information gained from them can be used by a surgeon in deciding his approach should surgery be necessary. Precise, detailed scans such as MRIs are also useful in monitoring the progress of a pituitary tumor or following up after surgery.
In addition, your endocrinologist may order other tests that are useful in diagnosing pituitary disorders including:
- Hormone testing
- Neuro-opthalmological evaluation, including a visual field exam. This involves looking at a screen with flashing lights and pressing a button when you see one of the lights. The pattern of which flashing lights you can or can't see maps areas of your vision affected by the tumor.
- Urinalysis. This involves collecting a sample of urine for chemical analysis. Because hormone levels naturally go up and down during the day and night, it may be necessary to do a 24-hour urine collection.
- Provocative / Suppressive lab tests. These are tests that are designed to cause or prevent hormones from being secreted to help identify the cause of a pituitary disorder. These include glucose tolerance tests to help diagnose acromegaly, arginine infusion tests to help detect growth hormone deficiency and dexamenthasone suppression tests and inferior petrosal sinus sampling to help diagnose Cushing's disease.