WHAT THE FOSSA????

Question 1

What in the Foramina of Cribiform Plate (anterior)?

Answer 1

CN I (Olfactory)

Question 2

What in the Optic Canal (middle)?

Answer 2

1. CN II (optic)

2. Opthalmic Artery

Question 3

What in the Superior Orbital Fissure (middle)?

Answer 3

1. Opthalmic Veins
2. CN III (oculomotor)
3. CN IV (trochlear)
4. CN V (1) (Opthalmic)
5. CN VI (Aducent)

Question 4

What in the Foramen Rotundum (middle)?

Answer 4

1. CN V (2) (Maxillary)

Question 5

What in the Foramen Ovale (middle)?

Answer 5

1. CN V (3) (Mandibular)
2. Accessory Menigeal a.
3. Lesser Petrosal n. (CN IX)

Question 6

What in the Carotid Canal (middle)?

Answer 6

1. Internal Carotid a.

2. Internal Carotid Nerve Plexus (Sympathetic)

Question 7

What in the Foramen Spinosum (middle)?

Answer 7

1. Middle Menigeal Vessels

Question 8

What in the Groove/Hiatus of Facial Canal (middle)?

Answer 8

1. Greater Petrosal n. (CN VII)

Question 9

What in the Groove/Hiatus of Lesser Petrosal Nerve (middle)?

Answer 9

1. Lesser Petrosal n. (CN IX)

Question 10

What in the Internal Auditory Meatus (posterior)?

Answer 10

1. Internal Auditory Vessels
2. CN VII (fascial)
3. CN VIII (Vestibulocochlear)

Question 11

What in the Jugular Foramen (posterior)?

Answer 11

1. Internal Jugular Vein
2. CN IX (Glossopharyngeal)
3. CN X (Vagus)
4. CN XI (Accessory)

Question 12

What in the Hypoglossal Canal (posterior)?

Answer 12

1. CN XII (Hypoglossal)

2. Emissary Vein

Question 13

What in the Foramen Magnum (posterior)?

Answer 13

1. Vertebral Arteries
2. CN XI (Accesory) nerve roots
3. **Caudal Brainstem/Spinal Cord
4. Anterior and Posterior Spinal Arteries

**Medulla Oblongata becomes continuous with spinal cord

Question 14

What in the Condyloid Canal (posterior)?

**DON’T Confuse with hypoglossal canal

Answer 14

1. Emissary Vein

Question 15

What in the Foramen Lacerum (middle)?

Answer 15

NOTHING - Closed to the exterior by cartilage

• Internal Carotid a. passes over f. lacerum as it enters cranial vault
• Greater petrosal nerve (VII) passes close as it heads to the pterygoid canal