THE CLINICAL SYNDROME

• Trigeminal neuralgia is a painful condition that affects many patients and is caused by the constriction of the trigeminal root as it emerges from the brainstem by convoluted blood vessels.

• Compression of the nerve can also be caused by conditions such as acoustic neuromas, cholesteatomas, aneurysms, angiomas, and anomalies in the bone.

• The pain that is caused by trigeminal neuralgia is second only to the pain that is caused by cluster headaches in terms of its severity.

• Suicide has been linked to uncontrolled pain, and as a result, this condition needs to be taken seriously and handled as an emergency.

• Daily actions that involve touch with the face, such as brushing one's teeth, shaving, or washing one's face, have the potential to set off an attack. In most people, medication can be used to successfully manage their pain.

• Multiple sclerosis is present in around 2% to 3% of patients who have been diagnosed with trigeminal neuralgia. There is another name for trigeminal neuralgia, which is tic douloureux.

SIGNS AND SYMPTOMS

• Trigeminal neuralgia causes recurring facial pain.

• The discomfort affects the same nerve on both sides in 97% of patients. Most patients are affected by the second or third nerve division, although fewer than 5% are affected by the first. 57% of single-sided facial pain cases start on the right side. Pain waves feel like electric shocks and last from a few seconds to two minutes. The effect starts and peaks almost instantly.

• Trigeminal neuralgia patients avoid triggers at all costs.

• Many people with facial pain, such as temporomandibular joint dysfunction, rub the bothersome area or administer heat or cold.

• Hospitalization is needed to quickly control trigeminal neuralgia. Patients report less pain between attacks.

• If the intense pain diminishes but the dull aching persists, a structural lesion may be squeezing the nerve.

• Multiple sclerosis is rarely diagnosed in those under 30.

TESTING

• When a new patient is diagnosed with trigeminal neuralgia, they should all undergo magnetic resonance imaging (MRI) of the brain and brainstem, both with and without gadolinium contrast medium, in order to rule out the possibility of posterior fossa or brainstem lesions as well as demyelinating disease.

• In addition, magnetic resonance angiography can be of assistance in determining whether or not the trigeminal nerve is being compressed by abnormal blood vessels.

• If there is a chance that the patient has occult or concurrent sinus disease, then further imaging of the sinuses should be considered.

• If the first division of the trigeminal nerve is affected, then it is suggested to have an ophthalmologic evaluation to evaluate the intraocular pressure and to rule out the possibility of intraocular disease.

• If the diagnosis of trigeminal neuralgia is uncertain, screening laboratory tests, which include a complete blood count, erythrocyte sedimentation rate, and automated blood chemistry, should be conducted.

• Before beginning treatment with carbamazepine, a full blood count is necessary so that baseline comparisons can be made.

DIFFERENTIAL DIAGNOSIS

• Trigeminal neuralgia is typically an easy clinical diagnosis that can be made on the basis of a focused history and physical examination.

• This is because trigeminal neuralgia is a condition that affects the trigeminal nerve.

• Trigeminal neuralgia can be confused with other conditions that can affect the eyes, ears, nose, throat, and teeth. These conditions can coexist and make the diagnosis more difficult.

• It is possible to differentiate between atypical facial pain and trigeminal neuralgia based on the quality of the pain experienced.

• A typical facial pain is described as a dull and aching sensation, but the pain associated with trigeminal neuralgia is described as being acute and neuritic.

• In addition, the pain that is associated with trigeminal neuralgia occurs in the distribution of the divisions of the trigeminal nerve, whereas the pain that is associated with atypical face pain does not follow any particular nerve distribution.

• When a patient presents with trigeminal neuralgia in their first four decades of life, a diagnosis of multiple sclerosis should be investigated for that patient.

TREATMENT

Drug Therapy Carbamazepine

• It is generally agreed that carbamazepine is the best therapy option for trigeminal neuralgia.

• In point of fact, a speedy response to this medication serves as virtually irrefutable evidence of the clinical diagnosis.

• In spite of the fact that carbamazepine is a safe and effective medication, there has been some uncertainty and worry around its use. This medicine, which may be the patient's greatest chance for pain control, is sometimes withdrawn because of laboratory abnormalities that are incorrectly attributed to it. This is unfortunate because the medication could have been the patient's only hope for pain relief.

• Before beginning treatment with the medication, it is necessary to do baseline measurements, which include a full blood count, a blood chemistry profile generated by an automated system, and a urinalysis.

Gabapentin

• In the extremely unlikely case that carbamazepine does not provide enough pain control for a patient, gabapentin may be considered as an alternative treatment option.

• As is the case with carbamazepine, baseline blood tests need to be performed prior to initiating treatment, and the patient needs to be warned about the possibility of experiencing adverse effects such as dizziness, drowsiness, confusion, and rash.

• The recommended starting dose of gabapentin is 300 milligrams taken before going to bed for a period of two nights. The dose of the medication is then gradually increased by 300 milligrams over the course of two days, with each day's total dose being divided evenly into the previous day's dose. This process is repeated until either pain relief is achieved or a total dose of 2400 milligrams per day is attained.

• If at this stage the patient has only had partial pain reduction, blood values will be tested, and the drug will be carefully titrated upward using 100-mg tablets. If the patient has received complete pain relief, the process will end here. It is extremely rare for a daily dose to be necessary that is more than 3600 mg.

Baclofen

• Baclofen could be beneficial for some people who are not helped by the anticonvulsant medications carbamazepine or gabapentin.

• Before beginning therapy with baclofen, baseline laboratory tests should be done, and the patient should be advised about the same potential bad effects that are associated with those other medications.

• The patient begins treatment with a single dose of 10 milligrams before going to bed for two consecutive nights.

• After that, the patient's dosage of the medication is increased by 10 milligrams over the course of seven days, with each increase being given in equally divided doses.

• This continues until the patient experiences relief from their pain or the maximum daily dosage of 100 milligrams is reached.

• This medication is known to cause serious adverse effects on the liver and the central nervous system, including lethargy and sedation.

• When using baclofen, it is recommended that laboratory readings be carefully monitored, same like when using carbamazepine.

Invasive Therapy

Trigeminal Nerve Block

• In addition to taking medication, a trigeminal nerve block that combines a local anesthetic and steroid can be an effective treatment for trigeminal neuralgia.

• During the process of titrating drugs to their optimal levels, this approach provides quick pain relief.

• The initial block is performed using bupivacaine that does not include any preservatives in conjunction with methylprednisolone.

• The subsequent daily nerve blocks are carried out in a manner quite identical to the initial one, albeit with a reduced quantity of methylprednisolone. This method may also be utilized to control breakthrough pain.

Retrogasserian Injection of Glycerol

• Patients suffering with trigeminal neuralgia who have not reacted well to appropriate medication therapy may find long-term relief from their symptoms through the injection of modest volumes of glycerol into the region of the gasserian ganglion.

• This treatment has been shown to be effective. Only a physician who is familiar with the risks and complications connected with neurodestructive operations should carry out this procedure.

Balloon Compression of the Gasserian Ganglion

• It is a simple procedure to put a balloon into Meckel's cave using a needle that has been guided by radiological imaging.

• The foramen ovale is the opening through which the needle is inserted. In order to compress the gasserian ganglion, the balloon must first be brought into close contact to it before being inflated.

• It has been demonstrated that this method can offer relief from the neural pain associated with trigeminal dysfunction in certain patients for whom the management of their pain with medication has been unsuccessful and who are not candidates for more invasive procedures.

Microvascular Decompression of the Trigeminal Root

• This operation, which is also known as the Jannetta's procedure, is the primary neurosurgical treatment that is recommended for patients who have intractable trigeminal neuralgia.

• Compressive mononeuropathy is what is thought to be the underlying cause of trigeminal neuralgia, according to this theory.

• The operation involves locating the trigeminal root close to the brainstem and disconnecting the blood artery that is squeezing it. After this, a sponge is placed between the vessel and the nerve in order to reduce the amount of compression and, consequently, the amount of pain experienced.

Gamma Knife

• The gamma knife is a non-invasive outpatient procedure that eliminates the area anterior to the junction of the trigeminal nerve and the pons, the trigeminal nerve entry site immediately adjacent to the pons, the midposterior portion of the trigeminal nerve, or the cisternal segment of the trigeminal nerve.

• This is accomplished through the focused emission of gamma rays from a cobalt source.

• Facial numbness and sensory deficits are examples of complications that can arise.

COMPLICATIONS AND PITFALLS

• The pain caused by trigeminal neuralgia is excruciating and has been linked to suicidal thoughts in some patients. Because of this, we have no choice but to treat it as a true medical emergency, and patients in this predicament should be admitted to the nearest hospital as soon as possible.

• After the severe pain associated with trigeminal neuralgia has subsided, if the patient continues to have a dull aching, this is strongly suggestive of persistent compression of the nerve by a structural lesion such as a brainstem tumor or schwannoma.

• Patients less than 30 years old almost never exhibit symptoms of trigeminal neuralgia unless the condition is accompanied by multiple sclerosis.

• Patients in this age group should all get an MRI to rule out the presence of a demyelinating disease.