Cranial Nerve Palsy - V : Trigeminal Nerve

Question 1

Anatomical Course of Trigeminal Nerve.

Answer 1

1. Originates from 3 Sensory Nuclei and 1 Motor Nucleus Between Midbrain and Medulla.
2. Sensory Nuclei merge at Pons Level to form Sensory Root.
3. Sensory Root expands into Trigeminal Ganglion.
4. Motor Root passes inferior to Sensory Root along floor of Trigeminal Cave to reach Mandibular Division only.

Question 2

Where is the Trigeminal Ganglion found?

Answer 2

Trigeminal Cave : Lateral to Cavernous Sinus (Depression of Temporal Bone).

Question 3

Branches of the Trigeminal Nerve (3).

Answer 3

1. V1 - Ophthalmic.
2. V2 - Maxillary.
3. V3 - Mandibular.

Question 4

Entries of the Branches of the Trigeminal Nerve (3).

Answer 4

1. Ophthalmic - Superior Orbital Fissure.
2. Maxillary - Foramen Rotundum.
3. Mandibular - Foramen Ovale.

Question 5

Ophthalmic Nerve Sensory Function.

Answer 5

Skin and mucous membranes of frontonasal prominence e.g. forehead to dorsal of nose.

Question 6

Ophthalmic Nerve Parasympathetic Function.

Answer 6

Lacrimal Gland.

Question 7

Corneal Reflex.

Answer 7

1. Afferent Limb : Ophthalmic Nerve.

2. Efferent Limb - Facial Nerve (Orbicularis Oculi).

Question 8

What is HZO?

Answer 8

Herpes Zoster Ophthalmic - reactivation of VZV in Ophthalmic Nerve : vesicular rash around eye and Hutchinson’s Sign.
Give oral antivirals for 7-10 days.

Question 9

What is Hutchinson’s Sign?

Answer 9

Rash on the tip or side of the nose : nasociliary involvement and ocular involvement.

Question 10

Maxillary Nerve Sensory Function.

Answer 10

Skin, Mucous Membranes and Sinuses of Maxillary Prominence.

Question 11

Maxillary Nerve Parasympathetic Function.

Answer 11

1. Lacrimal Gland.

2. Nasal Gland.

Question 12

Mandibular Nerve Sensory Function.

Answer 12

Skin, mucous membranes of floor of mandibular prominence - oral cavity floor, external ear, lower lip, chin, anterior 2/3 tongue general sensation and teeth.

Question 13

Mandibular Nerve Branches.

Answer 13

1. Buccal Nerve.
2. Inferior Alveolar Nerve.
3. Auriculotemporal Nerve.
4. Lingual Nerve.

Question 14

Mandibular nerve Parasympathetic Functions (3).

Answer 14

1. Submandibular Glands.
2. Sublingual Glands.
3. Parotid Glands.

Question 15

Significance of Mandibular Nerve.

Answer 15

Local Anaesthetic in Dental Procedures to Inferior Alveolar Nerve.