HERSHEY – Facial pain can have many causes, but trigeminal neuralgia or tic douloureaux can be particularly severe and often sends patients on a desperate search for a clinician who can help. Those suffering from trigeminal neuralgia often describe it as a severe lancinating or electric pain that usually involves only one side of the face. The pain is often restricted to a region of the face on that side, such as the jaw or eye. Though the pain is usually intermittent in nature, it is often severe, and attacks can last for an extended period of time. These attacks can often be triggered by stimulation of the face or mouth. Such innocent stimuli as a breeze on the face, brushing teeth, shaving or eating cold foods can bring on a sudden and severe episode of this excruciating pain. This disorder most commonly affects people over the age of 50, though it can be seen in younger patients as well.
Even though it is a fairly common disorder, it is not uncommon for patients suffering from trigeminal neuralgia to see a variety of specialists before a definitive diagnosis can be made, because it can mimic other disorders. Temporomandibular joint pain and dental pain can both be similar in nature. Trigeminal neuralgia will not respond to treatments for these other disorders because it is a disorder of the trigeminal nerve. This is the nerve that transmits sensory information from the face to the brain and is frequently compressed by a blood vessel, usually an artery in trigeminal neuralgia.
Treatment of trigeminal neuralgia usually starts with medical management. The symptoms almost always respond to the anti-epileptic medication carbemazepine. Unfortunately, the relief is sometimes incomplete or the side effects are not well tolerated. If that is the case, there are a variety of other medications that also can be used, and any medication that controls the pain with little or no side effects is certainly an acceptable and appropriate treatment.
In situations where medical management does not provide satisfactory pain relief, or causes unacceptable side effects, there are surgical options available. The goal of these treatments is to control the pain — with or without medication. There are several surgical approaches available. An open surgical procedure known as microvascular decompression often offers the most long-term relief. This procedure involves a traditional operation with general anesthesia. The trigeminal nerve is exposed where it exits the brainstem, and the offending vessel is moved away from the nerve. The nerve is then usually padded with a Teflon pad. Though this usually offers the best long-term relief, it comes with significant risk and recovery. For older patients, the vessel itself can be so hard and twisted from atherosclerosis that it can be difficult to move. As a result, this procedure is often not the best choice for older patients. For them, lesioning procedures are often a better option. In these procedures, the goal is to injure the nerve in order to prevent it from conducting these abnormal pain signals.
One class of lesioning procedures involves introducing a needle through the face to where the trigeminal nerve exits the skull. There, using heat, alcohol or compression, the nerve can be injured. Usually after this procedure the patient experiences good pain relief almost immediately. Unfortunately, these procedures are almost never a permanent cure to the problem, though they can be repeated if the pain recurs.
Another option is Gamma Knife radiosurgery. Here the goal is still to injure the nerve, but the technique is entirely different. Here the nerve is injured with radiation, which is a largely painless process. The most dramatic part of this procedure is the attachment of a stereotactic frame to head. This frame is a localization device that allows for the meticulous accuracy required for this procedure. It is affixed to the skull with four aluminum pins, which are placed with a local anesthetic. The patient then has an MRI study, which allows the surgeon to localize the nerve. A plan is then developed to target the nerve and treat it with large doses of radiation.
The Gamma Knife is a focused radiation technique which means that multiple low dose beams are aimed at the same point. As a result, even though radiation goes through everything in the head, the only place where the radiation is high enough to cause damage is at the point where the beams meet. This is where the nerve is positioned, through the use of the stereotactice frame. Patients usually tolerate the painless delivery of radiation without difficulty and go home the same day after the frame is removed. The biggest drawback to radiation is that it works over time. It can take two weeks to several months for the lesion to fully mature. Nevertheless, the long-term pain relief is very good. For patients who have infrequent attacks, or whose attacks are partially controlled by medication are often excellent candidates for Gamma Knife radiosurgery. Arguably, radiosurgery is the best tolerated of all of these procedures and, like the other lesioning procedures, it also can be repeated.