S1: Cranial Nerves (I, II, III, IV, VI) Flashcards
Course of Olfactory Nerve
Lesions in Olfactory Nerve Cause …..
- Anosmia
- Parosmia
Def of Anosmia
Loss of smell
Causes of Anosmia
- Congenital
- Acquired
Causes of Anosmia
- Congenital
….
Causes of Anosmia
- Acquired
- Local Infection in nose
- Lesion in olfactory tract
- Lesion in olfactory Cortex
Acquired Causes of Anosmia
- Lesions of the olfactory tract
Acquired Causes of Anosmia
- Lesions of the olfactory cortex
Unilateral Anosmia = ……
Bilateral Anosmia = ………
- Neurological
- ENT
Def of Parosmia
- abnormal unpleasant smell with or without a persistent unpleasant olfactory hallucination.
Causes of Parosmia
- Head injury
- Depressive illness
What does Optic Nerve represent?
- The optic nerve are the axons of the ganglion cells of the retina.
Course of Optic Nerve
- Decussation
(Fibres from the temporal half of The retina pass without crossing, while fibres from the nasal half of the retina decussate to the opposite side)
Course of Optic Nerve
- Clinical Significance for Light Reflex
—-> The Lateral Geniculate Body
- (where the majority of fibres terminate and a small portion subserving the light reflex, bypass the geniculate body to reach the Edinger Westphal nucleus on both sides and pass to ciliary ganglia and from there a new set of fibres extend to the sphincter pupillae muscles).
Course of Optic Nerve
- The main arterial supply of the visual cortex is the …..
PCA
Course of Optic Nerve
- The Macula receives additional supply from the ……
MCA
Lesions in Optic Nerve
Lesions in Optic Nerve
- 1
Lesions in Optic Nerve
- 2
Lesions in Optic Nerve
- 3
Lesions in Optic Nerve
- 4
Lesions in Optic Nerve
- 5
Lesions in Optic Nerve
- 6
Muscles supplied by Occulomotor Nerve
- All muscles supplied by 3 except SO4 & LR6
Course of Occulomotor Nerve
Occulomotor Nerve
- CP of 3rd Nerve Palsy
Course in Trochlear Nerve
Supply by Trochlear Nerve
- It enters orbit through the SOF, It terminates on the superior oblique muscle of the opposite side to the nucleus of origin.
Lesions of Trochlear Nerve
4th Nerve Palsy
Course of Abducent Nerve
Muscles innervated by Abducent Nerve
Lateral Rectus
Lesion in Abducent Nerve
- Paralysis of the lateral rectus muscle.
- Convergent squint.
- Diplopia apparent on abduction.
6th Nerve Palsy
- Paralysis of the lateral rectus muscle.
- Convergent squint.
- Diplopia apparent on abduction.