The cranial nerves are 12 pairs of nerves that emerge from the brain and are responsible for providing motor and sensory functions. They are among the most delicate nerves in the human nervous system and require experts who specialize in their normal and abnormal presentations.
Cranial nerve issues can affect a motor nerve, called cranial nerve palsy, or affect a sensory nerve, causing pain or diminished sensation. Individuals with a cranial nerve disorder may suffer from symptoms that include intense pain, vertigo, hearing loss, weakness or paralysis. These disorders can also affect smell, taste, facial expression, speech, swallowing, and muscles of the neck.
Cranial Nerve Conditions
Trigeminal neuralgia, or Tic Douloureux, is a disorder of the fifth cranial nerve, the trigeminal nerve, a large nerve that carries sensation from the face to the brain. Pain associated with the trigeminal nerve can be severe and intense, usually only on one side of the face, often around the eye, cheek, and lower part of the face. Pain may be triggered by touch or sounds and can occur while a person is brushing their teeth, eating, drinking, or shaving.
This disorder can be caused by a tumor, or multiple sclerosis, or when blood vessels press on the root of the trigeminal nerve. Trigeminal neuralgia is initially treated the same as atypical facial pain (e.g. medications). If medications fail, however, then it can be treated with neurosurgical intervention.
Trigeminal neuralgia is diagnosed based on clinical presentation. Ancillary tests such as blood tests, dental examinations, and magnetic resonance imaging (MRI) scans are used primarily to rule out other possible diagnosis.
A hemifacial spasm is a neurological disorder in which blood vessels constrict the seventh cranial nerve, causing muscles on one side of the face to twitch or 'tic' involuntarily. Hemifacial spasm can be caused by several factors: facial nerve injury, a blood vessel touching a facial nerve, or a tumor. Although these twitches are uncomfortable, they are usually not life-threatening.
As the disorder progresses, you may experience spasms in the muscles of the lower face which may affect your mouth to be slightly pulled to the side. You may start to experience discomfort and pain. If left untreated, a hemifacial spasm can cause all muscles of the face to twitch and spasm.
Hemifacial spasm is diagnosed based on clinical presentation--the characteristic twitch or tic is the best evidence of the condition. However, additional tests including the detection of a brain tumor, will need to be performed to confirm a hemifacial spasm.
Glossopharyngeal neuralgia is a compression of the ninth cranial nerve and causes brief but excruciating pain at the base of the tongue which can radiate to the ear and neck. The pain can last for a few seconds to a few minutes and may return multiple times in a day or once every few weeks. Typical triggers often include eating, drinking, swallowing, speaking, sneezing, or coughing. Glossopharyngeal can also occur in people with throat or neck cancer.
If left untreated, glossopharyngeal neuralgia can worsen, causing longer, frequent attacks of excruciating pain.
Diagnosis is based on clinical presentation. If glossopharyngeal neuralgia is suspected, the doctor may request an MRI, MRA, or CT scan. The doctor may also attempt to trigger an episode by touching the back of the mouth or tonsils. If that causes pain, a topical anesthetic is applied to the back of the mouth and the test repeated. If pain is not triggered after topical anesthetic is applied, glossopharyngeal neuralgia is diagnosed.
Skull Base Tumors
Many skull base tumors, also know as cranial base tumors. These tumors involve cranial nerves and cause double vision, vision loss, hearing loss, and/or dizziness. Examples of tumors that affect cranial nerves and are tackled by skull base surgery include: acoustic neuroma, pituitary adenoma, meningioma, craniopharyngioma, hemangiopericytoma, chordoma, and chondrosarcoma. Patients may have subtle symptoms for a long period of time before the tumor is diagnosed.
A diagnosis is made with advanced imaging such as a CT scan or an MRI scan. We work closely with our colleagues in ENT to craft the appropriate surgical procedure to remove the tumor and restore cranial nerve function.
When to See a Penn Neurosurgeon
Typically patients with cranial nerve disorders see a neurosurgeon after they have seen a neurologist. These patients have either failed medical management or cannot tolerate the side effects of medications.
A consultation with a neurologist who specializes in treating cranial nerves is beneficial because there are medications which may be useful in relieving the pain associated with these conditions. A thorough neurological examination, including various testing options, can be performed to properly identify and diagnose a cranial nerve disorder.
If medical management is not effective, then neurosurgical options can be discussed. If you have been diagnosed with a cranial nerve disorder and would like a second opinion, please call 800-789-7366 (PENN).
Second Opinion for Cranial Nerve Disorders
Many individuals seek a second opinion from Penn's neurosurgeons to help decide what the best treatment might be for their cranial nerve disorder. During a second opinion, a Penn neurosurgeon will review your medical history, current diagnosis and any images that have been taken. It is very important to bring all images, regardless of how long ago they were taken.