Cranial Nerves - Olfactory Optic Oculomotor Abducent Trochlear - examination bed side clinical disease abnormality

1. SHORT TOPIC – CRANIAL
NERVES I, II, III, IV, VI
CHAIR PERSON – DR. KALINGA B.E
STUDENT – DR. SALMAN M.B

3. OLFACTORY NERVE

5. CAUSES OF SMELL LOSS
 ELDERLY
 NASAL CAUSES
 TOXINS, PESTICIDES, HEAVY METALS
 TRAUMA
 OLFACTORY GROVE MENINGIOMA
 FRONTAL LOBE TUMOUR

6.  PARKINSONS DISEASE
 ALZHIEMERS DISEASE
 KALLMANS SYNDROME
 CONGENITAL ANOSMIA
 LOBECTOMY
 IATROGENIC CAUSES

7. OPTIC NERVE

17. II CRANIAL NERVE
EXAMINATION
 VISUAL ACUITY
 FIELD OF VISION
 COLOUR VISION
 FUNDOSCOPY

18. VISUAL ACUITY
 SNELLENS CHART

19.  JAEGERS CHART

20. COLOUR VISION

22. VISUAL FIELD TESTING
 CONFRONTATION TESTING
 AMSLER GRID
 PERIMETRY
 CAMPIMETRY
 HUMPHREY’S VISUAL FIELD ANALYSER
 GOLDMANS PERIMETRY

25. NORMAL VISUAL FIELD

26. FUNDOSCOPY
 DIRECT FUNDOSCOPY

27. NORMAL FUNDUS

28. LOCALIZATION OF BASED ON
DISORDER OF VISUAL
FUNCTION
 PRECHIASMAL
 CHAISMAL
 RETROCHAISMAL

29. PRECHAISMAL
 MACULA
 OPTIC DISC
 OPTIC NERVE

30. LOCALIZATION OF OPTIC
NERVE LESION

33. CRANIAL NERVES III, IV, VI

34. OCCULOMOTOR NERVE

36. SUB NUCLEI
 Each oculomotor nucleus consists of multiple
adjacent subnuclei that innervate specific
ocular muscles
 The neurons are somatic motor (general
somatic efferent).
 The paired lateral nuclei are the largest and
are situated anterior and lateral to the others;
their medial portions are fused into an
unpaired mass.

37.  The lateral subnucleus innervates the
ipsilateral inferior oblique, ipsilateral inferior
rectus and medial rectus.
 This forms the inferior division of the third
nerve

38.  Superior rectus is innervated by contralateral
medial subnucleus.
 Central caudal nucleus supplies LPS on both
sides.
 EW nucleus provides the parasympathetic supply
to the eyes
 These three form the superior division of the third
nerve

40.  So the filaments forming the third nerve are
1. Ipsilateral lateral subnucleus
2. Contralateral medial subnucleus
3. Central caudal nucleus
4. EW nucleus

42.  Through the nerve’s subarachnoid course, the
parasympathetic fibers lie superficially on the
dorsomedial surface. The location of these
fibers influences whether a third nerve palsy
will or will not involve the pupil, an important
differential diagnostic point

44. TROCHLEAR NERVE

46. ABDUCENS NERVE

49. SUPRANUCLEAR CONTROL OF
GAZE
 HORIZONTAL GAZE CENTER – PPRF
 VERTICAL GAZE CENTER – ROSTRAL
MIDBRAIN

50.  SACCADES
 PURSUITS
 VERGENCE
 FIXATION
 OPTOKINETIC
 VESTIBULO-OCULAR

51. SACCADES

53.  PPRF WITH BURST AND PAUSE NEURONS
 STEP CELLS IN PERIHYPOGLOSSI AREA

54.  DORSOLATERAL PREFRONTAL CORTICAL
AREA
 ANTI SACCADES

55. PURSUITS

57. VERTICAL GAZE
 ROSTRAL INTERSTITIAL NUCLEUS OF MLF
 LATERAL PORTION ( DORSAL ) – UPGAZE
 MEDIAL PORTION (VENTRAL) –
DOWNGAZE
 CAUDAL INTERSTITIAL CELLS OF CAJAL

58. THE MEDIAL LONGITUDINAL
FASICULUS
 MLF, an extensive and prominent fiber tract
that runs in the midline in the dorsal
tegmentum of the brainstem.
 It coordinates lateral gaze by connecting the
sixth nerve nucleus on one side with the third
and fourth nerve nucleus of the opposite side,
allowing the two eyes to move synchronously.

59.  Lesions affecting MLF – INTER NUCLEAR
OPTHALMOPLEGIA (INO)

62. CLINICAL EXAMINATION
 EXOPTHALMOS
 ENOPTHALMOS
 PDEUDO PROPTOSIS
 PULSATILE PROPTOSIS

63. PTOSIS
 EXAMINATION
 BILATERAL PTOSIS
 UNILATERAL PTOSIS
 SEESAW PTOSIS, CURTAIN SIGN
 CENTRAL PTOSIS
 SENILE INVOLUTIONAL PTOSIS
 PSEUDOPTOSIS

66. LID RETRACTION
 LID LAG IN PRIMARY GAZE
 LID LAG IN DOWNWARD GAZE

67. PUPILS
 NORMAL SIZE
 MIOSIS
 MYDRIASIS
 SHAPE
 EQUALITY

68. DISORDERS OF THE PUPIL
 LARGE PUPILS
1. III NERVE PALSY
2. UNCAL HERNIATION
3. ANEURSYMS
4. ADIES TONIC PUPIL
5. TECTAL PUPILS
6. PHARMACOLOGICAL

69.  SMALL PUPILS
1. PHARMACOLOGICAL
2. OPIATES
3. NEUROSYPHILIS
4. OP POISONING

71. THE PUPILLARY REFLEXES
 THE LIGHT RESPONSE
 THE NEAR RESPONSE
 CILIOSPINAL REFLEX
 OCULOPUPILLARY REFLEX
 COCHLEOPUPILLARY REFLEX
 VESTIBULOPUPILLARY REFLEX
 PSYCHIC REFLEX

72. LIGHT REFLEX PATHWAY

73.  HORNERS SYNDROME
 ARGYLL ROBERTSON PUPIL
 AFFERNT PUPILLARY DEFECT
 AMAUROTIC PUPIL

74. EYE MOVEMENTS
 DUCTION
 VERSION
 VERGENCE
 3 AXIS
 FIXATION POINT
 SHERRINGTON’S LAW
 HERING’S LAW

75. DIPLOPIA
 MONOCULAR / BINOCULAR
 HORIZONTAL / VERTICAL
 NEAR / FAR
 TRANSIENT / PROLONGED
 COMPENSATORY MECHANISMS

76. EXAMINATION OF THE EYE
MOVEMENTS
 9 CARDINAL POINTS
 PURSUITS (IPSILATERAL PATIETO
OCCIPITAL PATHWAY)
 SACCADES

77. EVALUATION OF OCULAR
MALALIGNMENT
 SUBJECTIVE TESTS
1. RED LENS TEST
2. MADDOX ROD TEST
 OBJECTIVE TESTS
1. CORNEAL LIGHT REFLEX TESTS
2. COVER TESTS

79. OPTOKINETIC NYSTAGMUS
 IPSILATERAL PURSUITS
 CONTRALATERAL SACCEDES
 COGAN’S RULE

81. DISORDERS OF OCULAR
MOTILITY
 PERPHERAL
 CENTRAL
1. SUPRANUCLEAR
2. INTERNUCLEAR

82. INDIVIDUAL NERVE PALSIES

83. OCCULOMOTOR NERVE
 INTERNAL OPTHALMOPLEGIA
 EXTERNAL OPTHALMOPLEGIA
 COMPLETE OPTHALMOPLEGIA
 COMPLETE III NERVE PALSY (33%)
 INCOMPLETE III NERVE PALSY (67%)

84. LOCALIZATION OF THE III
NERVE PALSY

86. LOCALIZATION OF THE IV
NERVE PALSY

88. LOCALIZATION OF THE VI
NERVE PALSY

89. REFERENCES
 DeJong’s The Neurologic Examination, 7TH
EDITION
 Localization clinical neurology, 6th edition –
PAUL W BRAZIS

90. THANK YOU