Which cranial nerve is involved in Tic Douloureux?
V CRANIAL NERVE (Trigeminal Nerve)
1). Sensory system – Ophthalmic div – forehead, nose.
Maxillary div – Malar region, upper lip
Mandibular div – Chin. lower lip
2). Motor system – Masseter ms. Q Temporalis ms. Q Pterygoid ms. Q
3). Reflexes –
a. Corneal reflex – Receptor → Free nerve ending (pain)
Aff → Trigeminal nerve Q Eff → Facial nerve Q
This reflex lost in any lesion involving this reflex arc. Also lost in lesion of parietal lobe.
b. Jaw Jerk– Exaggerated in pseudobulbar palsy.Q
c. Blink reflex/ glabellar reflex/ orbicularis oculi reflex.
Aff – Trigeminal nerve Q Eff – Facial nerve Q
CLINICAL FEATURES –
1). Nuclear lesion →
a. This occur due to diseases affecting pons, medulla and upper cervical cord upto C2
b. CAUSES -
Tumour, Demyelination, Vascular lesion, Syringomyelia, Syringobulbia.
2). Pontine lesion – Ipsilateral atrophy and weakness of the muscles of mastication along with ipsilateral facial sensory loss with C/L hemiplegia.
3). Lower medulla & upper cervical cord
a. Ipsilateral loss of pain and temp. over the face and C/L hemiplegia.
b. CAUSES – Tumour, abscess, Herpes zoster.
c. It is associated with a number of complications like pain, uveitis, keratitis and corneal perforation.
Reader’s paratrigeminal syndrome –
a. This results due to lesion close to the Gasserian ganglion.
b. Severe unilateral facial pain and headache in the distribution of the ophthalmic division of the trigeminal nerve in combination with ipsilateral oculosympathetic palsy or Horner syndrome without facial anhidrosis (as the sudomotor fibres to the face are not involved i.e. sweating is preserved on the side of the lesion.).
Post ganglionic lesions –
CAUSES – cavernous sinus lesion (III, IV, VI also)
Gradenigo’s syndrome (ophth + Max div. + VI + Retrobulbar pain)
Petrous apex Mastoiditis - Gradenigo’s syndrome = Deafness, diplopia, headache, Ipsilateral VI palsy
Cavernous sinus Thrombus III, IV, V, VI, N lesion
Trigeminal Neuralgia (Ref. Hari-18th ed., pg- 3361)
1). Paroxysm of intense pain in the distribution of fifth nerve usually Unilateral, mainly in the mandibular and maxillary area due to anomalous intracranial vessel and compressing trigeminal root.
2). Face screw up with pain (Dic douloureux) triggering factors are face wash, eating, shaving.
3). Patient are usually above 50 years
4). Secondary causes are aneurysm, tumor, multiple sclerosis
1). Drugs therapy
2). Surgical therapy. (Ref. Hari-18th ed., pg- 3361)
a. The most widely used method currently is microvascular decompression to relieve pressure on the trigeminal nerve as it exits the pons.
b. Gamma knife radiosurgery is also utilized for treatment and results in complete pain relief in more than two-thirds of patients
c. Another procedure, radiofrequency thermal rhizotomy, creates a heat lesion of the trigeminal (gasserian) ganglion or nerve.