Occulomotor Nerve

Question 1

Functional component

Answer 1

General somatic efferent fibres- supply extraocular muscles except SO4 and LR6- somatic motor nucleus
General visceral efferent fibres- sphincter pupillae and ciliaris muscle- parasympathetic comp of occulomotor nucleus (Edinger Westphal nucleus)

Question 2

Course till division

Answer 2

Oculomotor sulcus- tentorial notch- middle cranial fossa- pierce dura- lateral wall of cavernous sinus- ant part of sinus divides into smaller upper and larger lower division- superior orbital fissure

Question 3

Course after division

Answer 3

Smaller upper, above optic nerve, superior rectum and levator palpebrae superioris
Larger lower- three branches- supply muscles.
Nerve to inf oblique gives parasym comp to ciliary ganglion.

Question 4

Lesions of oculomotor occur because of?

Answer 4

Aneurysm of post comm artery
Aneurysm of int carotid artery
Transtentorial uncal herniation

Question 5

Clinical features of damage

Answer 5

Ptosis 
Lateral strabismus
Dilated and fixed pupil
Loss of accommodation
Diplopia 
Proptosis