Trigeminal nerve maxillary nerve and clinical implication
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The document discusses the maxillary branch of the trigeminal nerve and its clinical implications. It begins by describing the basic anatomy of neurons, nerves and cranial nerves. It then focuses on the trigeminal nerve as the fifth cranial nerve, describing its nuclei, ganglion and three main branches - the ophthalmic, maxillary and mandibular nerves. Most of the document details the anatomy and branches of the maxillary nerve, including those in the pterygopalatine fossa, orbit, infraorbital canal and face. It concludes by discussing three clinical implications - trigeminal neuralgia, herpes zoster ophthalmicus and Wallenberg syndrome.
Trigeminal nerve maxillary nerve and clinical implication
- 1. MAXILLARY BRANCH OF TRIGEMINAL NERVE AND ITS CLINICAL IMPLICATION
- 2. REFERENCES • Churchill livingstone. Gray’s anatomy Anatomy of the human body 39th edition.2008 • Rajendran A & Sundaram S.Shafer’s textbook of oral pathology 7th edition
- 3. • The nervous system of man is made up of innumerable neurons which further constitute the nerve fibers Nerve : A bundle of fibers that uses chemical and electrical signals to transmit sensory and motor information from one body part of the body to another. Neurons : These are specialized cells that constitute the functional units of the nervous system and has a special property of being able to conduct impulses rapidly from one part of the body to another.
- 4. • The cranial nerves are composed of twelve pairs of nerves that emanate from the nervous tissue of the brain. In order to reach their targets they must ultimately exit/enter the cranium through openings in the skull. Hence, their name is derived from their association with the cranium.
- 5. NERVE IN ORDER • Cranial Nerve I - Olfactory Cranial Nerve II - Optic Cranial Nerve III - Occulomotor Cranial Nerve IV - Trochlear Cranial Nerve V - Trigeminal Cranial Nerve VI - Abducens Cranial Nerve VII - Facial Cranial Nerve VIII- Vestibulocochlear Cranial Nerve IX - Glossopharyngeal Cranial Nerve X - Vagus Cranial Nerve XI - Spinal Accessory Cranial Nerve XII - Hypoglossal
- 6. CLASSIFICATION OF CRANIAL NERVES • Sensory cranial nerves: contain only afferent (sensory) fibers • ⅠOlfactory nerve • ⅡOptic nerve • ⅧVestibulocochlear nerve • Motor cranial nerves: contain only efferent (motor) fibers • Ⅲ Oculomotor nerve • ⅣTrochlear nerve • ⅥAbducent nerve • Ⅺ Accessory nerv • Ⅻ Hypoglossal nerve • Mixed nerves: contain both sensory and motor fibers • ⅤTrigeminal nerve, • Ⅶ Facial nerve, • ⅨGlossopharyngeal nerve • ⅩVagus nerve
- 7. EMBRYOLOGY OF THE NERVE • During the development of embryo, the pharyngeal arches appear in the fourth and fifth week. It give rise to six pharyngeal arches, of which the 5th arch disappears. • Each arch is characterized by its own: muscular component nerve component arterial component skeletal component • Trigeminal nerve is derived from 1st pharyngeal arch
- 8. NUCLEI OF TRIGEMINAL NERVE:- • It has got 4 nuclei : 1) Mesencephalic nuclei 2) Spinal nuclei sensory 3) Main sensory nuclei 4) Motor nuclei
- 9. SENSORY NUCLEI : • 1.Mesencephalic nucleus. Situated in midbrain. First order sensory nucleus. Cell body of pseudounipolar neurons. Recieves general somatic afferent fibres. Relay proprioception from : -muscles of mastication -facial muscles -eye
- 10. 2.MAIN SENSORY NUCLEUS Situated in upper part of pons lateral to motor nucleus. Receives general somatic afferent fibers. Relays impulses of touch and pressure from skin and mucous membrane of facial region.
- 11. 3.THE SPINAL NUCLEUS: • it extends from caudal end of principal sensory nucleus in pons to 2nd or 3rd spinal segment where it continues with sub. Gelatinosa. Divided into three parts :- 1. Subnucleus oralis 2. Subnucleus interpolaris 3. Subnucleus caudalis It receives general somatic afferent fibres Relays the impulses of pain and temperature of face
- 12. 4.THE MOTOR NUCLUES :- • It is situated in upper pons medial to principal sensory nucleus. • Contains efferent fibres. • Innervates muscles of mastication and tensor tympani and tensor palatini.
- 13. THE TRIGEMINAL GANGLION :- Also known as Gasserian ganglion or semilunar ganglion, is a sensory ganglion of the trigeminal nerve that occupies a cavity (Meckel’s cartilage) in the durameter, covering the trigeminal impression near the apex of the petrous part of the temporal bone.
- 14. • It is somewhat crescentic or semilunarin shape, with its convexity directed anteriomedialy. The three divisions of the trigeminal nerve emerges from this convexity. • Trigeminal nerve is the largest cranial nerve. • It is a mixed nerve. • Composed of a small motor root and a considerably larger sensory root. • The sensory root contains 170000 fibres and the motor root contains 7700 fibres.
- 17. THE MAXILLARY NERVE: It is intermediate division of trigeminal nerve. Wholly sensory. ORIGIN: It leaves the trigeminal ganglion between the ophthalmic and mandibular divisions as a flat plexiform band Passes slightly medial to lateral wall of cavernous sinus. Leaves the cranium through foraman rotandum, which is located in the greater wing of sphenoid bone.
- 18. • Once outside the cranium, it crosses the uppermost part of the pterygopalatine fossa, between the pterygoid plates of sphenoid bone and the palatine bone As it crosses the pterygopalatine fossa it gives of branches sphenopalatine ganglion zygomaticbranches posterior superior alveolar nerve
- 19. • It then angles laterally in a groove on the posterior surface of the maxilla, entering the orbit through the inferior orbital fissure • Within the orbit it occupies the infraorbital groove and becomes the infraorbital nerve,which courses anteriorly into the infraorbital canal • The maxillary division emerges on the anterior surface of face through the infraorbital foramen, where it divides into its terminal branches, supplying the skin of the face, nose, lower eyelid and upper lip
- 22. MENINGEAL NERVE: Also known as nervus meningeus medius. It lies within the cranium. It receives a ramus from the internal carotid sympathetic plexus and accompanies the middle meningeal artery to supply the duramater.
- 23. BRANCHES THROUGH PTERYGOPALATINE FOSSA: • ZYGOMATIC NERVE:- • Starts in the pterygopalatine fossa. Enters the orbit through the inferior orbital fissure. Divides into two branches. Zygomaticcotemporal: supplying sensory innervation to skin on the side of the forehead. Zygomaticofacial: supplying the skin on the prominence of the cheek.
- 24. • Before leaving the orbit the zygomatic nerve communicates with the lacrimal nerve of the ophthamic division which carries secretory fibres from pterygopalatine ganglion to lacrimal gland.
- 25. POSTERIOR SUPERIOR ALVEOLAR NERVE • It descends from the main trunk of the maxillary division in the ptergopalatine fossa. Through the pterygopalatine fossa,it reaches the inferior temporal surface of the maxilla. From here it enters maxilla through the psa canal
- 26. Travel down the posteriolateral wall of the maxillary sinus. Provides sensory innervation to the mucous membrane of the sinus. Continuing downward it provides sensory innervation to the alveoli,periodontal ligaments,and pulpal tissues of the maxillary 3rd ,2nd and 1st molar. Applied anatomy:-During a nerve block there is great risk of hematoma formation .
- 27. THE PTERYGOPALATINE NERVE: This nerve turns straight downward after it has left the trunk of the second division The pterygopalatine ganglion is attached to the medial side of the nerve.
- 28. • Branches of pterygopalatine nerve includes those that supply four areas:- orbit nose– a) superior posterior nasal medial lateral b) nasopalatine palate- a) greater (anterior) b)lesser (middle & posterior) pharynx The orbital branches supply the periosteum of the orbit.
- 29. • The superior posterior nasal branches are given off at the level of the ganglion. Enter the nasal cavity through the sphenopalatine foramen. Lateral branches of superior posterior nasal nerve supply upper and middle conchae. Medial branches of the nerve pass over the roof of the nasal cavity to the nasal septum, one of the medial branches is distinguished by its great length and by its diagonal course downward and forward along the nasal septum,it is called the nasopalatine nerve. The nasopalatine nerve gives off branches to the anterior part of the nasal septum and the floor of the nose
- 30. • Enters the incisive canal , passes into oral cavity via the incisive foramen, located in the midline of the palate about 1cm posterior to the maxillary central incisors. The right and left nasopalatine nerves emerge together through this foramen and provide sensation to the palatal mucosa in the region of premaxilla ( canine to central incisor)
- 31. GREATER PALATINE NERVE: Emerges on the hard palate through the greater palatine foramen (usually located about 1cm towards the palatal midline, just distal to the second molar) The nerve courses anteriorly supplying sensory innervation to the palatal soft tissues and bone as far as the first premolar, where it communicates with the terminal fibres of the nasopalatine nerve. It provides sensory innervation to some parts of soft palate
- 32. THE MIDDLE PALATINE NERVE: Emerges from the lesser palatine foramen along with the posterior palatine nerve . Provides sensory innervation to the mucous membrane of soft palate The posterior palatine nerve: Innervates the tonsillar region.
- 33. THE PHARYNGEAL BRANCH: It is a small nerve Passes through the pharyngeal canal and is distributed to the mucous membrane of the nasal part of the pharynx posterior to the auditory tube.
- 34. BRANCHES IN THE INFRAORBITAL CANAL: • The nerve enters the orbit through the inferior orbital fissure, and is then called the infra orbital nerve passing through the infra orbital canal. Within the canal it gives of two branches: middle superior anterior superior alveolar branch alveolar branch
- 35. THE MIDDLE SUPERIOR ALVEOLAR NERVE (MSA): • Arises from the infra orbital nerve. Provides sensory innervation to two maxillary premolars and perhaps to the mesiobuccal root of the first molar and the periodontal tissues, buccal soft tissues and bone in the premolar region. Traditionally it has being stated that the MSA nerve is absent in 30% to 54% of individuals. In its absence the usual innervations are provided by either the PSA or the ASA nerve, most frequently the latter.
- 37. THE ANTERIOR SUPERIOR ALVEOLAR NERVE (ASA): It is a relatively larger branch Given off from the infraorbital nerve at approximately 6 to 10mm before the latter exit from the infraorbital foramen It provides pulpal innervation to the: central and lateral incisors canine periodontal tissues buccal bone mucous membrane of these teeth.
- 38. BRANCHES ON THE FACE: The infraorbital emerges through the infraorbital foramen onto the face to divide into its terminal branches: 1) the inferior palpebral:- supplying the skin of the lower eyelid 2) the external nasal branch:- providing sensory innervation to skin of lateral part of the nose 3) the superior labial branch:- supplying the skin and mucous membrane of the upper lip.
- 39. APPLIED ANATOMY :- • 1.Trigeminal neuralgia. 2. Herpes zoster ophthalmicus. 3.Wallenberg Syndrome.
- 40. TRIGEMINAL NEURALGIA:- also known as Fothergill’s disease Tic douloureux (painful jerking) it is defined sudden, usually, unilateral, severesuas , brief, stabbing , lancinating, recurring pain in the distribution of one or more branches of trigeminal nerve. Mean age: 50 y onwards Female predominance (male : female = 1:2 ~2:3)
- 41. PATHOGENESIS OF TRIGEMINAL NEURALGIA • It is usualy idiopathic. The probable etiologic factors are:- Intra cranial tumors:-Traumatic compression of the trigeminal nerve by neoplastic or vascular anomalies eg arteriovenous malformations Infections : infections involving 5th cranial nerve. • Intracranial vascular abnormalites
- 42. GENERAL CHARACTERISTICS Incidence:- seen in about 4 in 100000 persons Age of occurrence:- 5th to 6th decade Sex predilection:-female predisposition Side involved more frequently:-right side Division of trigeminal nerve involve; most commonly mandibular > maxillary >ophthalmic
- 43. CLINICAL CHARACTERISTICS:- Sudden Unilateral sharp shooting lancinating shock like pain elicted by slight touching superficial trigger points which radiates across the distribution of one or more branches of the trigeminal nerve pain rarely crosses the midline pain is of short duration and last for few seconds to minutes in extreme cases patient has a motionless face called the frozen or mask like face presence of intraoral or extraoral trigger points
- 44. TRIGGER ZONE
- 45. • Provocated by obvious stimuli like Touching face at particular site Chewing Speaking Brushing Shaving Washing the face The characteristic of the disorder being that the attacks do not occur during sleep.
- 47. DIAGNOSIS:- CLINICAL EXAMINATION with HISTORY is mandatory Response to treatment with tablet of carbamazepine is univeral Injections of local anaesthetic agents into patients trigger zone gives temporarily relief from pain.
- 48. TREATMENT • Medical treatment • Surgical treatment:- • Peripheral injections • Peripheral neurectomy • Cryotherapy • Peripheral radiofrequency • Neurolysis(thermocoagulation) • Carbamazapine and phenytoin are the traditional anticonvulsants given primarilary. The dosage of the drug used intially should be kept small to minimum especialy in elderly patients to avoid nausea, vomiting and gastric irritation.
- 49. THE ALCOHOLIC INJECTIONS:- • 95% ABSOLUTE alcohol in small quantites 0.5 to 2 ml is given in peripheral branches of trigeminal nerve. Side effect:- Repeated injections may cause Local tissue toxicity Inflammation Fibrosis
- 50. HERPES ZOSTER OPHTHALMICUS:- • Caused by Varicella zoster Predilection for nasociliary branch of ophthalmic division of the trigeminal nerve CLINICAL FEATURES:- Cutaneous lesions:- Rash Vesicle Pustule crust permanent scar
- 51. OCULAR LESIONS:- Eyelid:- Perorbital pain Oedema Hyperasthesia Conjunctivitis Corneal scarring
- 52. TREATMENT:- • Acyclovir 800mg 5 times /day within 4 days of onset of rash Analgesics Antibiotic ointments Systemic steroids 60mg/day Corneal grafting
- 53. THANK YOU
Editor's Notes
- #10: 1.The first order sensory neurons are in the dorsal root ganglia or the sensory ganglia of cranial nerves. 2. The second order sensory neurons are in the dorsal gray column or various sensory nuclei of the brainstem. 3. The third order sensory neurons are in the thalamic nuclei. The long ascending sensory tracts found in the spinal cord or the brainstem are formed by either the first or the second order neurons. EXAMPLE: Typically, the perception of pain travels through three orders of neurons. The first-order neurons carry signals from the periphery to the spinal cord; the second-order neurons relay this information from the spinal cord to the thalamus; and the third-order neurons transmit the information from the thalamus to the primary sensory cortex, where the information is processed, resulting in the "feeling" of pain
- #11: The nerves responsible for sensing a stimulus and sending information about the stimulus to your central nervous system are called afferent neurons. The nerves that carry signals away from the central nervous system in order to initiate an action are called efferent neurons.
- #42: Intra cranial tumors:-Traumatic compression of the trigeminal nerve by neoplastic (cerebellopontine angle tumor) or vascular anomalies eg arteriovenous malformations Infections :- granulomatous and non granulomatous infections involving 5th cranial nerve. Postherpetic neuralgia Demyelinating conditions Multipleasclerosis (MS) Petrous ridge compression
- #48: PERIPHERAL RADIOFREQUENCY NEUROLYSIS THERMOCOAGULATION:- Radiofrequency electrode that has the capacity to destroy the pain fibres is used in this procedure. Temperature being 65 to 75 degree C for 1 to 2 minutes. Shown to induce pain remissions in 20%of cases. .
- #49: Peripheral neurectomy (nerve avulsion):- Oldest and the most effective procedure Simple Direct application of cryotherapy probe (nitrous oxide probe) Temperature colder than -60 degree C,for 2-3 minutes Reapeated three times Produces WALLERIAN degeneration without destroying the nerve sheath Relatively reliable Indicated in patients in whom craniotomy is contraindicated due to age,debility,limited life expectancy Acts by interrupting the flow of a significant number of afferent impulses to central trigeminal apparatus. Performed mostly on infraorbital,inferior alveolar,mental and rarely lingual nerve. CRYOTHERAPY FOR PERIPHERAL NERVE:-
- #53: Wallenberg syndrome:- a stroke which causes loss of pain/temperature sensation from one side of the face and the other side of the body. ETIOLOGY:- In the medulla, the Ascending Spinothalamic Tract (which carries pain/temperature information from the opposite side of the body) is adjacent to the Descending Spinal Tract of the fifth nerve (which carries pain /temperature information from the same side of the face) A stroke cuts off the blood supply to this area Destroys both tracts simultaneously. Results in loss of pain/temperature sensation in a unique “checkerboard” pattern (ipsilateral face, contralateral body) Characteristic diagnostic feature.