Craniopharyngioma

Diagnosis

After getting the patient's medical history, physicians at Mayo Clinic conduct a neurologic exam to help determine whether a patient has a craniopharyngioma. During this procedure a physician tests the patient's vision, hearing, balance, coordination, and reflexes. Patients may also be tested for any changes in hormone levels. Physicians may then order one or more of the following imaging studies.

• Computed tomography (CT) scan. A CT scan uses a sophisticated X-ray machine linked to a computer to produce detailed, two-dimensional images of the brain. Patients lie on a movable table that technicians guide into an enormous tube where images are taken. In some cases a special dye may be injected into the bloodstream to make tumors more visible on the images.
• Magnetic resonance imaging (MRI) scan. This technology uses magnetic fields and radio waves to generate images of the brain. MRI scans show the contour of soft tissues as well as bone. Occasionally radiologists use a special dye injected into the bloodstream to help distinguish tumors from healthy tissue.
• Angiogram. A special dye injected into the bloodstream helps locate blood vessels in and around the craniopharyngioma on an X-ray.
• Other brain scans. Other tests help doctors gauge brain activity by studying brain metabolism and chemistry and blood flow within the brain. Some tests include magnetic resonance spectroscopy (MRS), single-photon emission computerized tomography (SPECT), and positron emission tomography (PET) scanning. These scans can be combined with MRIs to help doctors understand the effects of the tumor on brain activity and function.

Sometimes a needle biopsy may be used to get a sample of the tumor tissue prior to surgery. Experienced pathologists examine the tissue in highly equipped laboratories.