This document provides information about the trigeminal, glossopharyngeal, and hypoglossal cranial nerves. It begins with an overview of the cranial nerves and their classifications. It then discusses the trigeminal nerve in depth, including its embryology, nuclei, pathways, ganglia, and clinical implications such as trigeminal neuralgia. The glossopharyngeal nerve is then summarized, covering its nuclei, course, branches and clinical tests. Finally, the hypoglossal nerve is outlined, with details on its nucleus, segments, branches, examining techniques, and causes of hypoglossal palsy. In total, the document comprehensively reviews the anatomy and clinical relevance of these three cranial

1. TRIGEMINAL,
GLOSSOPHARYNGEAL
AND HYPOGLOSSAL NERVES
PRESENTED BY
MANTHRU NAIK
1ST YEAR PG
GUIDED BY
Dr. K. SUREKHA MDS
PROF. & HEAD
Dr. G. SUDHAKAR MDS
ASST. PROF.

2. NERVEINORDER
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
CLASSIFICATION OF CRANIAL NERVES
Sensory cranial nerves(special sensory fibers ): I, II, VIII
Motor cranial nerves(somatic efferent nerves ): III, IV, VI, XI, XII
Mixed nerves (branchiomeric nerves ): V, VII, IX, X
FUNCTIONAL COMPONENTS OF
NERVES
1) General Somatic Afferent (GSA)
2) General Visceral Afferent (GVA)
3) General Visceral Efferent (GVE)
4) General Somatic Efferent (GSE)
5) Special Somatic Afferents (SSA)
6) Special Visceral Afferents (SVA)
7) Special Visceral Efferents (SVE)
INTRODUCTION

3. ELEMENTARYSTRUCTUREOFA TYPICALNEURON

4. TYPES OF NEURON
1-UNIPOLAR
2-BIPOLAR
3-MULTIPOLAR
4-PSEUDOUNIPOLAR

5. TRIGEMINALNERVE

6. EMBRYOLOGYOFTRIGEMINALNERVE
Trigeminal nerve is derived from 1st pharyngeal arch

7. NUCLEI OFTRIGEMINALNERVE
1) Mesencephalic nuclei
2) Main sensory nuclei
3) Spinal nuclei
4) Motor nuclei
sensory

9. FUNCTIONAL PATHWAYS OFTRIGEMINAL NERVE

10. TOUCH PATHWAYFROM THE HEAD

11. PAIN & TEMPERATURE PATHWAY

12. ATTACHMENT OFTRIGEMINAL
NERVE TO BRAIN

13. TRIGEMINAL GANGLION

15. RELATIONS OF TRIGEMINAL GANGLION
Foramen lacerum

16. Medial relations

17. TRIGEMINAL NERVE

18. THE OPHTHALMIC DIVISION
COURSE

19. BRANCHES

22. GANGLIAASSOCIATEDWITH THE TRIGEMINALNERVE
CILIARY GANGLION
a- occulomotor nerve
b- internal carotid plexus
c- nasociliary nerve
n- inferior oblique muscle

23. OPHTHALMIC NERVE NUT
SHELL

24. SUPRAORBITAL
SUPRATROCHLEAR
LACRIMAL
REGION OF
NASOCILLIARY
AREA OF DISTRIBUTION

25. COURSE
MAXILLARY DIVISION

26. CRANIUM
PTERYGOPALATINE
FOSSA
INFRAORBITAL
CANAL
FACE
BRANCHES

28. SUPERIORALVEOLAR NERVES

29. PTERYGOPALATINEGANGLION
ROOTS

30. BRANCHES

31. NASOPALTINE AND GREATER PALATINE NERVES
2) Nasopalatine nerve 4) Greater palatine nerve
5) Lesser palatine nerve

32. ZYGOMATIC
REGION
SUPERIOR
ALVELOLAR
REGION
INFRAORBITAL
REGION
AREA OF DISTRIBUTION

33. MAXILLARY NERVE NUT SHELL

34. COURSE
MANDIBULAR DIVISION

35. BRANCHES OF MAIN TRUNK
(2)

36. BRANCHES OF ANTERIOR DIVISION

38. BRANCHES OF POSTERIOR DIVISION
(2 )

39. LINGUALNERVE

41. INFERIOR ALVEOLAR NERVE
INFERIORALVEOLAR
NERVE
LINGUAL NERVE
INFERIORALVEOLAR
ARTERY
SPHENOMANDIBULAR
LIGAMENT

42. BRANCHES
Mylohyoid nerve

43. OTIC GANGLION

45. Preganglionic
parasympathetic fibers
Inferior salivatory nucleus
in medulla
glossopharyngeal N.jugular foramen
Glossopharyngeal n. tympanic branch of
IX
tympanic plexus
lesser petrosal nerveotic ganglion
postganglionic
parasympathetic fibers otic ganglion
auriculotemporal branch
(CN V)parotid gland

46. SUBMANDIBULAR GANGLION

47. SECRETOMOTOR PATHWAYTO SUBMANDIBULAR
AND SUBLINGUALGLAND

48. AREA OF DISTRIBUTION
AURICULO-
TEMPORAL
BRANCHESOF
BUCCAL
INFERIOR ALVEOLAR AND
MENTAL

49. MOTOR ROOT OF TRIGEMINALNERVE

50. MANDIBULAR NERVE NUT SHELL

51. OVERALLDISTRIBUTION OF TRIGEMINALNERVE

52. EXAMINATION OF TRIGEMINAL NERVE
SENSORY FUNCTION
MOTOR FUNCTION
V1
V2 V3
BULK OF MASSETER STRENGTH OF JAW OPENING

53. TRIGEMINAL REFLEXES
CORNEAL REFLEX JAW JERK REFLEX

54. CLINICAL APPLICATIONS OFTRIGEMINAL NERVE
TRIGEMINAL GANGLION
Trigeminal neuralgia (tic douloureux)
The paratrigeminal syndrome
Wallenberg syndrome

55. TRIGEMINAL NEURALGIA
PAIN
sudden ,usually ,unilateral ,severe ,
brief ,stabbing , lancinating ,
stereotyped and recurring pain

56. SYMPTOMS

57. TRIGGER POINTS

58. TYPES OF TRIGEMINAL NEURALGIA
CLASSI TN
SYMPTOMATIC TN

59. AETIOLOGY
Usually idiopathic
Other etiological factors include

60. COMMON PATTERNS OF VASCULAR
COMPRESSION OF TRIGEMINALNERVE
(JANNETA, 1967)

61. Intra cranial tumors - cerebellopontine angle
tumors
Postherpetic neuralgia
Multiple sclerosis (MS)
Infections

62. PATHOGENESIS
Demyelination
Hyperactivity or abnormal discharge of impluses
(ignition hypothesis - Devor et al )
Ephaptic cross- talk between fibres

63. Ephaptic cross- talk between fibres
Touching trigger points causes pain

64. DIAGNOSIS
Sweet diagnostic criteria
1. Pain is paroxysmal
2. The pain may be provoked by light touch to the face
(trigger zones)
3. The pain is confined to the trigeminal distribution
4. The pain is unilateral
5. The clinical sensory examination is normal
DIAGNOSTIC MRI SCANNING

65. DIFFERENTIAL DIAGNOSIS

66. Differentiation from atypical facial pain

67. TREATMENT
Medical treatment
Surgical treatment
Peripheral injections(anaesthetic agent or
95% absolute alcohol)
Peripheral neurectomy
Cryotherapy
Peripheral radiofrequency
Neurolysis(thermocoagulation)
Gasserian ganglion procedures

68. TREATMENT ALGORITHAM

69. MEDICALTREATMENT

70. HOWADRUG FOR SEIZURES IS
USEFUL IN THE TREATMENT OF
NEUROPATHIC PAIN ?

71. MICROVASCULAR DECOMPRESSION
Craniotomy Vascular compression
Teflon sponge placed Fixation of Ti plate
SURGICAL TREATMENT

72. RHIZOTOMY PROCEDURES
Percutaneous glycerol rhizotomy Balloon compression rhizotomy

73. Stereotactic Radiosurgery (Gamma Knife)
Attachment of a frame Beams of cobalt radiation are precisely
focused

74. Percutaneous stereotactic radiofrequency
rhizotomy (PSR)
Preparation of the patient Insertion of electrode
Identification of site of pain Application of heat

75. Peripheral Rhizotomies Microsurgical Rhizotomy

77. Wallenberg syndrome

78. OPHTHALMIC DIVISION
Ethmoid tumours
Nasal fractures
Supraorbital injuries
Bilateral cleft lip and palate
Herpes zoster ophthalmicus
MAXILLARY DIVISION
Infraorbital injuries (malar fractures)
Maxillary antrum tumours
Maxillary sinus infections
Maxillary teeth abscesses
Anaesthetic nerve blocks
Sphenopalatine ganglioneuralgia( brain freeze)
Dendritic fluoresceine uptake from HZO

79. MANDIBULAR DIVISION
Lingual nerve
Inferior alveolar nerve
Mental nerve neuralgia
Mumps
Submandibular duct
Superficial temporal artery biopsy

80. THEAURICULOTEMPRAL NERVE
SYNDROME(FREYSYNDROME)
Mechanism of frey’s syndrome
Sweating and flushing in area supplied
by auriculotemporal nerve

81. GLOSSOPHARYNGEAL NERVE

82. Glossopharyngeal nerve nuclei
FUNCTIONAL MODALITIES: SVE, GVE, GVA, SVA, GSA
Am - Nucleus ambiguus I s - Inferior salivary nucleus
Sol - Nucleus tractus salitarius spT - Spinal tract ofV nerve

83. COURSE

84. BRANCHES

85. TYMPANIC BRANCH

86. OUTLINE OF GLOSSOPHARYNGEAL NERVE

87. Effects of Damage and Clinical Test
 Gag reflex
 Ask the patient to swallow or cough
 Test the posterior one-third of the tongue with
bitter and sour substances.

88. CLINICALIMPLICATIONS
GLOSSOPHARYNGEALNEURALGIA
DRUGS
TEGRETOL
NEURONTIN
(GABAPENTIN)DILANTIN
LIORESAL
(BACLOFEN)
Diagnostic test

89. HYPOGLOSSALNERVE

90. HYPOGLOSSALNUCLEUS

91. Segments of the hypoglossal nerve

92. Hypoglossal
nerve
Vertebral arteries
COURSE
Hypoglossal nucleus, medullary & cisternal segments

93. Suprahyoid carotid space segment

94. Sublingual segment

95. BRANCHES OFHYPOGLOSSALNERVE

96. Hypoglossal nerve nut shell

97. EXAMINING THE HYPOGLOSSAL NERVE

98. HYPOGLOSSALPALSY
 Unilateral palsy is merely troublesome, resulting
in difficulty with speech, tongue biting during
mastication of food, and difficulties in swallowing
for as long as four months postoperatively
 Bilateral palsy can pose a life-threatening
situation by producing upper airway obstruction
 Hypoglossal palsy can be due to iatrogenic
injuries to hypoglossal nerve or due to lesions
affecting it.

99. IATROGENIC INJURIES OFHYPOGLOSSALNERVE
During
 Dissection of floor of submandibular triangle
 Blind application of hemostats and monopolar
coagulation to ranine veins
 Dissection in level I and II during RND
 carotid endarterectomy
 High exposure of internal carotid artery

100.  The use of transverse neck incisions has probably
served to increase the number of injuries to the
hypoglossal nerve and the marginal mandibular
nerve.
 The incision is close to, and parallels, the course
of both nerves.

101. DISSECTION IN SUBMANDIBULAR TRIANGLE
First Surgical Plane: The Roof of the Submandibular Triangle
•Composed of skin, superficial fascia enclosing the platysma muscle and fat, and
the underlying mandibular and cervical branches of the facial nerve (VII)
The Roof of the Submandibular Triangle

102. Second Surgical Plane:The Contents of theSubmandibular
Triangle
 Structures of the second surgical plane, from superficial to deep,
are
facial (anterior facial) vein
retromandibular (posterior facial) vein
part of the facial (external maxillary) artery
submental branch of the facial artery
superficial layer of submaxillary fascia (deep cervical fascia)
lymph nodes
deep layer of submaxillary fascia (deep cervical fascia)
hypoglossal nerve (XII)

103. Contents of submandibular triangle

104. Third SurgicalPlane:The Floorof the SubmandibularTriangle
 Structures of the third surgical plane, from superficial to deep
mylohyoid muscle with its nerve
hyoglossus muscle
middle constrictor muscle covering the lower part of the superior
constrictor muscle
part of the styloglossus muscle

105. Fourth Surgical Plane: The Basement of the
SubmandibularTriangle
 Deep portion of the submandibular gland
 Submandibular (Wharton's) duct
 Lingual nerve
 Sublingual vein
 Sublingual gland
 Hypoglossal nerve (XII)
 Submandibular ganglion

106. The Basement of the Submandibular Triangle

107. RANINE VEIN
 Ranine vein is vena comitans of hypoglossal nerve which
begins below the tip of the tongue.
 Inadvertent clamping while controlling bleeding from
plexus posterior and inferior to the posterior belly of
digastric muscle can result in hypoglossal nerve injury

108. HIGHEXPOSURE OFINTERNALCAROTIDARTERY
DURING CAROTID ENDARTERECTOMY
 The hypoglossal nerve, because of its intimate relationship to the
internal carotid artery, may limit exposure since it crosses the internal
carotid artery at various levels in different individuals, from just above
the carotid bifurcation to as high as the level of the anterior belly of
the digastric muscle. It usually crosses the ICA and ECA
approximately 2 to 4 cm above the carotid bifurcation
 Frequently, in order to visualize the uppermost extent of carotid
bifurcation plaques, to deal with internal carotid kinks or internal
carotid aneurysms the hypoglossal nerve may be retracted, resulting in
temporary paralysis of one-half of the tongue
 Never attempt to separate the hypoglossal and vagus nerves if they
fuse together

109. STRUCTURESTETHERING HYPOGLOSSALNERVE
Sternocleidomastoid artery
and vein
Occipital artery
Descends hypoglossi
Digastric muscle
Stylohyoid muscle

110. METHODS OFATRAUMATIC MOBILISATION OF
HYPOGLOSSALNERVE
By dividing sternocleidomastoid artery

111. By dividing occipital artery, descendens hypoglossi, digastric muscle

112. By mandibular subluxation
A – orotracheal intubation
B - nasotracheal intubation
C – mandibular subluxation

113. CONDITIONSAFFECTING HYPOGLOSSAL
NERVE

114. REFERENCES
 GRAY’S ANATOMY- 39TH EDITION
 NETTER’S- COLOUR ATLAS OF ANATOMY
 B.D.CHAURASIA’S HUMAN ANATOMY- VOL 3
 CRANIAL NERVES – FUNCTIONAL ANATOMY, STANLEY
MONKHOUSE
 Handbook of LOCAL ANESTHESIA- Stanley F. Malamed
 Trigeminal neuralgia- Pathology & pathophysiology Seth Love &
Hugh b. Coakham
 Trigeminal nerve- Sashank prasad and Steven Galetta
 INTERNET SOURCES
 Vascular reconstructions : anatomy, exposures, and techniques amal J
Hoballah