How to Test for Neurofibromatosis

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Doctors diagnose neurofibromatosis based on a combination of findings, including having a family history of the disease. They also look for typical signs and symptoms of the disease, order and review imaging studies, and sometimes order genetic testing. Some of these tests confirm a diagnosis of NF, help doctors know which of the three main types of NF a patient has or rule out NF. Here are some of the testing and other methods used to diagnose neurofibromatosis:

• Physical Exam and Family Medical History
  • Examining the patient to detect physical characteristics of the disease
  • Using special lamps to detect café au lait spots and other skin conditions
• Neurofibromatosis Genetic Testing
  • Performed by direct gene mutation analysis or linkage analysis using blood samples from family members
  • Helpful when a clinical diagnosis is inconclusive
  • Helpful for patients lacking known family history
  • Can help to correctly diagnose those with NF 2 or Schwannomatosis
  • Can confirm the disease in other family members
  • Can confirm a diagnosis of other rare genetic diseases or mutations that are similar to neurofibromatosis
• Prenatal Genetic Testing
  • Helpful during pregnancy to prepare for a child with NF
  • May include genetic counseling for those deciding to become pregnant
  • Will not always identify Schwannomatosis since many genes may be involved
• Pathology and Biopsy
  • It may be necessary to remove a tumor or section of tumor and examine it under a microscope to confirm the diagnosis of Schwannomatosis
  • Tissue samples (neurofibroma pathology samples) may be required for those who are the first in their family to get NF through a gene mutation since the mutation may not be present in all the body’s cells
• Imaging Tests
  • Magnetic resonance imaging (MRI) – Uses a magnetic field and radio waves to produce detailed images of the brain and spinal cord. Can confirm the presence of schwannomas on peripheral nerves or tumors on the brain and spinal cord, especially very small tumors or optic gliomas
  • Computed tomography (CT) scan – Confirms bone abnormalities or the presence of tumors
  • Electromyography (EMG) – A nerve conduction study (NCS) that measures electrical pathways in the nerves
  • X-ray images – Confirms bone abnormalities
• Hearing and Auditory Tests
  • Hearing (audiometry, brainstem auditory evoked response) and other imaging tests to detect tumors in or near the auditory nerves, brain or spinal cord and assess function of the eighth cranial nerve
• Eye Exam
  • Confirms the presence of Lisch nodules
  • Confirms the presence of cataracts
  • Confirms vision loss
  • Electronystagmography test can record eye movements to detect balance issues

Ongoing Testing and Monitoring for Neurofibromatosis

Imaging tests can be used to monitor NF 1 and Schwannomatosis. Children with NF 1 should be checked regularly (at six- or twelve-month intervals) for physical developmental changes along with learning and behavioral changes. In addition, they should be checked for new or changing skin growths and spots. Any abnormalities noticed may indicate the need for further testing or treatment. Patients with NF 2 should have similar routine care with known growths monitored and checked for changes.

There are many ongoing and new studies being performed for NF genetic disorders. It is important to have a neurofibromatosis specialist evaluate you or your child in order to help prevent additional damage caused by enlarging tumors. Working with a specialist also ensures that patients have access to new medical findings and treatment options as they become available.

Please call our office to set up an appointment. Our experienced staff can explain all aspects of testing, diagnosis and treatment.