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DEFINITION
 Trigeminal
neuralgia (TN), or
Tic Douloureux,
(also known as
prosopalgia ) is a neuropathic disorder of the trigeminal
nerve that causes episodes of intense pain in the eyes,
lips, nose, scalp, forehead, and/or jaw. Trigeminal neuralgia
is considered by many to be among the most painful
of conditions. An estimated 1 in 15,000 people
suffers from trigeminal neuralgia, although numbers
may be significantly higher due to frequent misdiagnosis.
It usually develops after the age of 40, although there
have been cases with patients being as young as three
years of age.
SYMPTOMS
The episodes of pain occur paroxysmally, or suddenly.
To describe the pain sensation, patients describe a
trigger area on the face, so sensitive that touching
or even air currents can trigger an episode of pain.
It affects lifestyle as it can be triggered by common
activities in a patient's daily life, such as toothbrushing.
Breezes, whether cold or warm, wintry weather or even
light touching such as a kiss can set off an attack.
The attacks are said to feel like stabbing electric
shocks or shooting pain that becomes intractable. Individual
attacks affect one side of the face at a time, last
several seconds or longer, and repeat up to hundreds
of times throughout the day. The pain also tends to
occur in cycles with complete remissions lasting months
or even years. 3-5% of cases are bilateral, or occurring
on both sides. This normally indicates problems with
both trigeminal nerves since one serves strictly the
left side of the face and the other serves the right
side. Pain attacks typically worsen in frequency or
severity over time. A great deal of patients develop
the pain in one branch, then over years the pain will
travel through the other nerve branches.
Although trigeminal neuralgia
is not fatal, successive recurrences may be incapacitating,
and the fear of provoking an attack may make sufferers
reluctant to engage in normal activities.
There is a variant of trigeminal neuralgia called
"atypical trigeminal neuralgia". In some
cases of atypical trigeminal neuralgia, the sufferer
experiences a severe, relentless underlying pain similar
to a migraine in addition to the stabbing pains. In other cases, the pain is stabbing and intense,
but may feel like burning or prickling, rather than
a shock. Sometimes, the pain is a combination of shock-like
sensations, migraine-like pain, and burning or prickling
pain. It can also feel as if a boring piercing pain
is unrelenting.
CAUSE
Trigeminal neuralgia is usually caused by a small blood vessel compressing the trigeminal nerve as it exits the brainstem. It can also be caused by multiple sclerosis (MS). MS patients who get trigeminal neuralgia are more likely to be younger at presentation, have bilateral symptoms at some point, and have atypical features. In rare cases trigeminal neuralgia can be caused by a mass against the trigeminal nerve such as a brain tumor. Work-up for suspected trigeminal neuralgia includes an MRI of the brain or CAT scan if the patient has a pacemaker or otherwise cannot get an MRI. Sometimes a special sequence MRI that focuses on the trigeminal nerve can also be helpful.
Treatments
Dr. Michael H. Brisman, Dr. Jeffrey A. Brown, and Dr. Alan Mechanic specialize in trigeminal neuralgia. Together, they are able to offer the full range of medical and surgical accepted options for the treatment of complex facial pain syndromes including trigeminal neuralgia.
Treatments for trigeminal neuralgia include medication and five different procedures (Microvascular decompression, radiofrequency rhizotomy, glycerol rhizotomy, balloon rhizotomy, and stereotactic radiosurgery). Atypical trigeminal neuralgia can also respond to the same treatments as “classic” trigeminal, though success rates are slightly lower. Medications used for trigeminal neuralgia are usually anti-seizure medicines, in particular “tegretol”, “trileptal”, neurontin” and “lyrica.” If medication is not helping or patients are experiencing side effects from the medication, then a procedure can be considered.
Surgery may be recommended, either to relieve the pressure on the nerve or to selectively damage it in such a way as to disrupt pain signals from getting through to the brain. In trained hands, surgical success rates have been reported at better than 90 percent.
Of the five surgical options, the microvascular decompression (MVD) is the only one aimed at fixing the presumed cause of the pain. In this procedure, the surgeon enters the skull through a 25mm (one-inch) hole behind the ear. The nerve is then explored for an offending blood vessel, and when one is found, the vessel and nerve are separated or “decompressed” with a small pad. When successful, MVD procedures can give permanent pain relief with little to no facial numbness.
“Nerve-Injuring” techniques can also be very effective in treating trigeminal neuralgia. These methods of nerve injury include “percutaneous” that is, through a needle, and “radiosurgery” i.e., with the use of super-focused radiation beams. These nerve injuring procedures are useful for patients who are elderly, have significant medical problems, have failed MVD, or have multiple sclerosis (in whom blood vessel compression is not felt to be the cause of the trigeminal neuralgia). The nerve-injuring techniques are minimally invasive, out-patient procedures. The main disadvantages to these techniques are first, some risk of producing numbness or dysthesias (abnormal feelings) in the face, and second, a higher chance of recurrence with time (because the nerve can regrow.)
Percutaneous trigeminal nerve injuring procedures, also known as “rhizotomies,” use needles or catheters that enter through the face into the opening where the nerve first splits into its three divisions. Excellent success rates using these “percutaneous” surgical procedures have been reported.These techniques include “radiofrequency”, glycerol” and “balloon” methods. In a radiofrequency rhizotomy, a surgeon uses an electrode to heat the selected division or divisions of the nerve. Done well, this procedure can target the exact regions of the errant pain triggers and disable them. This technique is particularly useful for patients with pain in the cheek or jaw, or the lower portions of the face. Glycerol rhizotomy involves injecting glycerol, an alcohol like substance, into the cavern that bathes the nerve. This liquid can injure the nerve just enough to disrupt the pain signals. Balloon compression involves compressing the nerve against the skull, again, just enough to stop the passage of pain signals. The balloon technique is particularly useful for patients with ophthalmic division pain, that is, pain in the forehead or eye.
Another procedure for treating trigeminal is stereotactic radiosurgery. In this technique, super-focused radiation beams are aimed at the nerve, to disrupt the pain signals. This procedure is a one day, minimally invasive, out-patient procedure, that does not require anesthesia. The procedure is done with only the most advances stereotactic radiosurgery devices such as the Gamma Knife, or specialized linear accelerators such as the Cyberknife. No incisions are involved in this procedure. Radiation is used to bombard the nerve root, targeting the same point where vessel compression is normally found. This procedure is particularly favorable for patients who are older, have serious medical problems, or who have to stay on blood thinners.
Doctors Brisman, Brown, and Mechanic have successfully treated hundreds of patients with trigeminal neuralgia, and combined have one of the largest trigeminal neuralgia practices in the New York Metropolitan Region.
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OUR TRIGEMINAL
NEURALGIA TEAM
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