Cranial Nerve V trigeminal nerve

Question 1

describe the corneal innervation?

Answer 1

epithelium, anterior and mid stroma are highly innervated

Question 2

are there nerves in the posterior stroma of the cornea?

Answer 2

NO

Question 3

when do corneal nerves become myelinated?

Answer 3

in the last 2mm of cornea

Question 4

what happens to corneal nerves after refractive surgery?

Answer 4

because of the corneal flap created the corneal nerves are cut up and a common symptom is dry eye . this is due to lack of input from the brain that the eyes are dry and this reduces blinking. the nerves do eventually heal

Question 5

V1 & V2 innervate the eyelids and palpebral conjunctiva, which nerves specifically?

Answer 5

V1 = Supraorbital nerve, supratrochlear nerve, infratrochlear nerve, lacrimal nerve

V2 innervates inferior eyelid specifically = infraorbital nerve , zygomatico- facial nerve

Question 6

what are the V1 dermatome areas?

Answer 6

sensation carried by trigeminal nerve 5

Question 7

Zygomatico temporal nerve innervates?

Answer 7

Sensory fibers from lateral forehead through
zygomaticotemporal foramen to orbit

Question 7

what is ophthalmic division V1 orbital exit? which are outside the common tendinous ring and which within?

Answer 7

branches exit orbit through SOF
outside= lacrimal nerve , frontal nerve

within= nasociliary nerve

Question 8

what are the V3 dermatome areas?

Answer 8

-AURICULOTEMPORAL
-BUCCAL
- INF. ALVEOLAR MENTAL

Question 9

Zygomaticofacial nerves innervates?

Answer 9

Fibers from lateral aspect of cheek and lower eyelid through zygomaticofacial foramen to orbit

Question 10

Infraorbital nerve innervates?

Answer 10

i) Sup. Labial: cheek, upper lip
ii) Inf. Palpebral: lower eyelid
iii) Nasal: side of nose

Question 11

Superior Alveolar nerves innervate?

Answer 11

-upper teeth & gums
- Ant. alveolar connects oral cavity to orbit as it connects directly to the infraorbital nerve inside the maxilla

Question 12

Pterygopalatine nerves innervate?

Answer 12

-hard & soft palate, tonsils, mucosa nasopharynx

Question 13

what are positive Hutchinsons signs? and what does it mean?

Answer 13

1. Presence of vesicles on nose tip = (+ sign)
   Increased chance of corneal involvement since
   distance from ganglion to nose tip is greater than distance from ganglion to cornea
   High chance of ocular complications with positive sign

Question 14

Herpes Zoster Ophthalmicus is caused by?

Answer 14

Reactivation of latent varicella-zoster virus
(VZV) in trigeminal ganglion

Question 15

Herpes Zoster Ophthalmicus is usually

Answer 15

unilateral and midline respecting
May result in reduced corneal sensation
May involve 1-3 adjacent dermatomes