Trigeminal Neuralgia

Roderick Agbuya

Definition

Sudden, usually unilateral, severe brief stabbing pain in the distribution of one of more branches of the V nerve (IASP)

Anatomy of Trigeminal nerve

There are three divisions of V nerve: ▪ The ophthalmic (V1) supplies sensation to upper

face including eyes. ▪ The maxillary (V2) supplies sensation to middle

face including upper teeth. ▪ The mandibular (V3) supplies sensation to lower

jaw including anterior two-thirds of tongue. All divisions come from the trigeminal ganglion,

also known as Gasserian ganglion. From the gasserian ganglion, sensory input is

conducted to the trigeminal nuclear complex.

Anatomy of Trigeminal NerveAnatomy of Trigeminal Nerve

Anatomy of Trigeminal NerveAnatomy of Trigeminal Nerve

Anatomy of Trigeminal NerveAnatomy of Trigeminal Nerve

Etiology and Pathophysiology

TN may be idiopathic (primary) or symptomatic (secondary).

Most cases of idiopathic TN are the result of vascular compression of V nerve near its entry into the pons

Symptomatic causes include: multiple sclerosis, tumors, and basilar artery aneurysm or ectasia.

Pathophysiology is not fully elucidated. Demyelinative lesions of trigeminal fibers appear to set up ectopic generation of spontaneous nerve impulses and their ephaptic conduction to adjacent fibers. This may disinhibit pain pathways in the spinal trigeminal nucleus.

Normal Trigeminal NerveNormal Trigeminal Nerve

Vascular compression of V nerveVascular compression of V nerve

Vascular irritation of V NerveVascular irritation of V Nerve

Tumor of V NerveTumor of V Nerve

Diagnosis

TN remains a clinical diagnosis.A careful search for ipsilateral dental

pathology should be undertaken.Routine imaging is generally not

indicated.MRI and MRA can be performed if

there is suspicion of underlying pathology.

Treatment

Medical treatment

Invasive treatment

Medical Treatment of TNMedical Treatment of TN

Trigeminal Nerve Block

Mandibular Nerve BlockMandibular Nerve Block

Mandibular Nerve BlockMandibular Nerve Block

Maxillary Nerve BlockMaxillary Nerve Block

Maxillary Nerve BlockMaxillary Nerve Block

Peripheral Block of V nerve Peripheral Block of V nerve

Percutaneous Radiofrequency Rhizotomy (Gasserian Ganglion

Block)It is widely used technique for

treatment of TN.Needle is introduced percutaneously

and passed through the foramen ovale

Then RF lesion is applied (Heating or Pulsed lesion)

Success rate reported more than 75%.

Percutaneous Radiofrequency RhizotomyPercutaneous Radiofrequency Rhizotomy

Glycerol Rhizotomy

Injection of 0.1 - 0.2 ml of glycerol into the Meckel’s cave, through a percutaneous needle placement.

High success rate with low morbidity has been reported

This procedure has a relatively high recurrence rate

Percutaneous Glycerol RhizotomyPercutaneous Glycerol Rhizotomy

Microvascular Decompression

Involves a craniotomy via the posterior fossa

This presumes the demonstration of vascular compression by MRI/MRA

High long-term success rate (above 70%) has been reported

Morbidity includes facial dysaesthesia, cerebellar injuries and hearing loss.

Microvascular Decompression of V nerveMicrovascular Decompression of V nerve

Microvascular Decompression of V nerveMicrovascular Decompression of V nerve

Microvascular Decompression of V nerveMicrovascular Decompression of V nerve

Microvascular Decompression of V NerveMicrovascular Decompression of V Nerve

Microvascular Decompression of V nerveMicrovascular Decompression of V nerve

Gamma Knife

Single high dose radiotherapy delivered with exquisite precision to a radiographically defined target, at the junction of trigeminal nerve and brain stem.

Several series of small numbers of patients report high rates of pain relief, with low rates of morbidity, mostly facial numbness.

Gamma KnifeGamma Knife

Gamma KnifeGamma Knife

Balloon Compression of Trigeminal Ganglion

It is done by introduction of a balloon via the percutaneous route

The balloon is then inflated with small volumes 0.5-1 ml of contrast until it occupies Meckel’s cave

Compression times vary from 1 to 6 minutes

Success rate are not dissimilar to other techniques.

Balloon Compression of Trigeminal GanglionBalloon Compression of Trigeminal Ganglion

Balloon Compression of Trigeminal GanglionBalloon Compression of Trigeminal Ganglion

Nursing Diagnosis

FearRisk for injuryPainAltered nutrition, less than body

requirements

Nursing Interventions

Instruct the client to avoid factors that can trigger the attack and result in exhaustion and fatigue.

Avoid foods that are too cold or too hot.

Chew foods in the affected side.Use cotton pads gently, wash face

and for oral hygiene.Provide teaching to clients who have

sensory loss as a result of a treatment.

Inspection of the eye for foreign bodies, which the client will not be able to feel, should be done several times a day.

Warm normal saline irrigation of the affected eye two to three times a day is helpful in preventing corneal infection.

Dental check ups every 6 months is encouraged, since dental caries will not produce pain.

Explain to the client and his family the disease and its treatments.