THE CLINICAL SYNDROME

• The term "atypical facial pain," which is synonymous with "atypical facial neuralgia," refers to a diverse set of pain syndromes that share the trait of having facial pain that does not fit the criteria for trigeminal neuralgia.

• Atypical facial pain is also known as "atypical facial neuralgia."

  • The pain is constant but can have varying degrees of severity.

  • Pain may be described as aching or cramping rather than the jolting, neuropathic pain that is typical with trigeminal neuralgia.

  • This condition nearly always affects only one side of the face.

  • The vast majority of individuals who report experiencing unusual face pain are female.

  • The pain can be localized to the area served by the trigeminal nerve, but it generally extends beyond the boundaries of the nerve's divisions.

• A headache is a common symptom of atypical facial pain and, from a clinical perspective, cannot be differentiated from tension-type headaches.

  • When it comes to the onset of atypical facial discomfort, stress is frequently a factor that either serves as a precipitating element or an exacerbating factor.

  • Many individuals also suffer from symptoms of depression as well as sleep disturbances.

  • In some individuals who are experiencing unusual facial pain, a history of facial trauma, infection, or malignancy of the head or neck may be elicited.

  • However, in the majority of cases, there is no identifiable precipitating event.

SIGNS AND SYMPTOMS

• In contrast to trigeminal neuralgia, which is characterized by abrupt paroxysms of pain similar to a neuritic shock, atypical face pain is continuous and has a dull, aching quality, but its intensity can vary.

• The pain associated with trigeminal neuralgia is usually contained within the confines of one division of the trigeminal nerve, whereas the pain associated with atypical face pain always extends beyond the boundaries of these divisions.

• Patients who suffer from atypical facial pain do not have the trigger sites that are typical of trigeminal neuralgia.

TESTING

• Patients who suffer from atypical facial discomfort typically have radiographs of the head that are within normal limits; however, radiographs of the head can be helpful in determining whether a tumor or bone abnormalities is present.

• An intracranial condition, such as a tumor, sinus illness, or infection, can be identified by a clinician with the assistance of magnetic resonance imaging (MRI) of the sinuses and the brain.

• In the event that inflammatory arthritis or temporal arteritis is suspected, it is important to conduct a complete blood count, an erythrocyte sedimentation rate test, and an antinuclear antibody test.

• The diagnostic procedure of injecting the patient's temporomandibular joint with a local anesthetic in very small amounts can be used to assess whether or not the temporomandibular joint is the cause of the patient's suffering.

• If the patient is also suffering considerable occipital or nuchal pain, an MRI of the cervical spine is another test that should be performed.

DIFFERENTIAL DIAGNOSIS

• It is possible for the clinical signs of atypical facial pain to be confused with pain that originates in the sinuses or the teeth, or they may even be incorrectly diagnosed as trigeminal neuralgia.

• The clinician can typically differentiate between these overlapping pain syndromes through careful questioning and assessment of the patient's physical state.

• It is possible for tumors of the zygoma and mandible, as well as tumors of the posterior fossa and retropharyngeal tissue, to produce ill-defined pain that is attributed to atypical facial pain.

  • These potentially life-threatening diseases need to be ruled out in any patient who is experiencing facial pain.

• Any patient who presents with facial discomfort that is not clearly characterized following an accident, an infection, or an injury to the central nervous system should also have reflex sympathetic dystrophy of the face evaluated.

• As was mentioned, atypical facial pain is characterized by a dull and aching sensation, whereas the pain that is associated with reflex sympathetic dystrophy of the face is described as being scorching in nature, and substantial allodynia is frequently present.

• The pain associated with reflex sympathetic dystrophy of the face reacts quickly to this sympathetic nerve block, however the pain associated with atypical facial pain does not respond in the same way.

  • This difference can be made clearer with the use of stellate ganglion block.

  • The pain of jaw claudication, which is related with temporal arteritis, needs to be differentiated from the atypical face discomfort that patients experience.

TREATMENT

• The combination of medication treatment with tricyclic antidepressants and physical modalities such as oral orthotic devices and physical therapy is the primary focus of treatment.

• This approach is considered to be the most effective.

  • A block of the trigeminal nerve and an intraarticular injection into the temporomandibular joint, both containing a steroid and a local anesthetic in very low doses, are two more potential treatments.

  • Antidepressants, like nortriptyline, taken as a single dose of 25 milligrams before going to bed will help reduce sleep disturbances and treat any myofascial pain syndrome that may be present.

• Patients who use orthotic devices are better able to prevent behaviors like clenching their jaws and grinding their teeth, both of which can make the clinical syndrome worse.

• The underlying depression and anxiety must also be managed in order to fulfill this need.

• Injections of botulinum toxin A into the muscle of mastication, in addition to the use of topical medications such as capsaicin, lidocaine, and a eutectic mixture of local anesthetics, may also be helpful in treating TMD.

• There is some evidence from case studies that a single inhalation of 25 mg of 9.4 tetrahydrocannabinol administered three times a day may help relieve neuropathic face discomfort.

COMPLICATIONS AND PITFALLS

• When treating patients who are assumed to be suffering from atypical facial pain, the most common mistake that can be made is to fail to recognize an underlying pathologic process that may be responsible for the patient's pain.

• This is the most common problem.

• Atypical face discomfort is primarily a diagnosis of exclusion rather than a specific condition.

• If a trigeminal nerve block or intraarticular injection of the temporomandibular joint is going to be a part of the treatment plan, the clinician needs to keep in mind that the region's vascularity and proximity to major blood vessels can lead to an increased incidence of postblock ecchymosis and hematoma formation, and the patient needs to be warned of this potential complication.

• If this is going to be a part of the treatment plan, the patient needs to be warned.