USMLE Forum Archives - USMLE Step 3 - Trigeminal Neuralgia
Trigeminal Neuralgia
meduploader - 05-14-09 13:43
At surgery or autopsy, intracranial arterial and, less often, venous loops compressing the
trigeminal nerve root where it enters the brain stem have been found, suggesting that the tic is a
compressive neuropathy.
Pain lasts from few seconds to minutes.
“Electric” like in character. Can be spontaneous or triggered by light touch, talking or eating.
Distributed trigeminally (usually second or third divisions), either alone or in combination
First division pain around the eye or forehead occurs in 10%-20% of patients, often with pain in other parts of the face, usually mid-cheek and upper lip or teeth
Usually unilateral
Pain is relieved by carbamazepine or oxcarbazepine but not narcotics or milder analgesics à Consider using carbamazepine administration as a diagnostic maneuver
Refractory period of pain after stimulation of the trigger area (cannot elicit pain again by touching or pushing immediately after a painful attack) à Highly predictive of trigeminal neuralgia.
Neurological exam is usually normal à Note that abnormal neurological findings are indicative of diseases other than trigeminal neuralgia.
Rx: Avoid PAIN triggers à Stay away from the direct blast of an air conditioner , Cover the face before going out into a cold wind, using covers that do not touch the face or that are not tight fitting , Avoid foods that trigger the pain for an individual patient (e.g., hot or cold drinks, foods that require much chewing)
Mild, infrequent pain à no treatment
Drug of choice for Trigeminal neuralgia à Oxcarbazepine or Carbamazepine
If pain persists, add another drug, such as gabapentin, baclofen, lamotrigine, or pregabalin
If pain continues despite drug therapy à needs neurosurgical intervention à gamma knife radiosurgery or percutaneous balloon microcompression of trigeminal division that is causing symptoms.
meduploader - 05-14-09 13:43
At surgery or autopsy, intracranial arterial and, less often, venous loops compressing the
trigeminal nerve root where it enters the brain stem have been found, suggesting that the tic is a
compressive neuropathy.
Pain lasts from few seconds to minutes.
“Electric” like in character. Can be spontaneous or triggered by light touch, talking or eating.
Distributed trigeminally (usually second or third divisions), either alone or in combination
First division pain around the eye or forehead occurs in 10%-20% of patients, often with pain in other parts of the face, usually mid-cheek and upper lip or teeth
Usually unilateral
Pain is relieved by carbamazepine or oxcarbazepine but not narcotics or milder analgesics à Consider using carbamazepine administration as a diagnostic maneuver
Refractory period of pain after stimulation of the trigger area (cannot elicit pain again by touching or pushing immediately after a painful attack) à Highly predictive of trigeminal neuralgia.
Neurological exam is usually normal à Note that abnormal neurological findings are indicative of diseases other than trigeminal neuralgia.
Rx: Avoid PAIN triggers à Stay away from the direct blast of an air conditioner , Cover the face before going out into a cold wind, using covers that do not touch the face or that are not tight fitting , Avoid foods that trigger the pain for an individual patient (e.g., hot or cold drinks, foods that require much chewing)
Mild, infrequent pain à no treatment
Drug of choice for Trigeminal neuralgia à Oxcarbazepine or Carbamazepine
If pain persists, add another drug, such as gabapentin, baclofen, lamotrigine, or pregabalin
If pain continues despite drug therapy à needs neurosurgical intervention à gamma knife radiosurgery or percutaneous balloon microcompression of trigeminal division that is causing symptoms.
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#1
Re: Trigeminal Neuralgia mtniharika - 09-27-09 04:09 Also called as tic douloureux.
PATHOPHYSIOLOGY,CAUSES AND D/D.
Unfortunately, the symptoms of trigeminal neuralgia are often falsely attributed to a pathology of dental origin.he pain is originating in the trigeminal nerve itself - often in its roots - and not in an individual nerve of a tooth, but real tooth pain may be referred to the same areas of the face as that of trigeminal neuralgia. Because of this difficulty, many patients may go untreated for long periods of time before a correct diagnosis is made.
The trigeminal nerve is the fifth cranial nerve, a mixed cranial nerve responsible for sensory data such as tactition (pressure), thermoception (temperature), and nociception (pain) originating from the face above the jawline; it is also responsible for the motor function of the muscles of mastication, the muscles involved in chewing but not facial expression.
Several theories exist to explain the possible causes of this pain syndrome. Leading research indicates that it is a blood vessel - possibly the superior cerebellar artery - compressing the microvasculature of the trigeminal nerve near its connection with the pons. Such a compression can injure the nerve's protective myelin sheath and cause erratic and hyperactive functioning of the nerve. This can lead to pain attacks at the slightest stimulation of any area served by the nerve as well as hinder the nerve's ability to shut off the pain signals after the stimulation ends. This type of injury may rarely be caused by an aneurysm (an outpouching of a blood vessel); by a tumor; by an arachnoid cyst in the cerebellopontine angle; or by a traumatic event such as a car accident or even a tongue piercing.
Two to four percent of patients with TN,usually younger,have evidence of multiple sclerosis, which may damage either the trigeminal nerve or other related parts of the brain. It has been theorized that this is due to damage to the spinal trigeminal complex. Trigeminal pain has a similar presentation in patients with and without MS.
When there is no structural cause, the syndrome is called idiopathic. Postherpetic Neuralgia, which occurs after shingles, may cause similar symptoms if the trigeminal nerve is affected.
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