Week 3: Station 5 - Floor of the Skull Flashcards
Which bone forms the posterior boundary of the anterior cranial fossa?
Sphenoid
Which bones form the
A) anterior boundary
B) floor
C) posterior boundary
of the middle cranial fossa?
A) Sphenoid
B) Sphenoid and temporal
C) Occipital
What is shown here and what 4 bones meet at this suture?
Pterion
- Frontal
- Temporal
- Parietal
- Sphenoid
Which bones form the anterior and posterior border of the posterior cranial fossa?
Anterior - temporal
Posterior - Occipital
- Cribriform plate
- Crista galli
- Anterior cranial fossa
- Optic canal
- Foramen rotundum
- Foramen ovale
- Foramen spinosum
- Foramen lacerum
- Sella turcica
- Foramen magnum
- Hypoglossal canal
- Jugular foramen
- Internal acoustic meatus
- Superior orbital fissure
- Incisive foramen
- Inferior orbital fissure
- Palantine foramen
- Pterygoid plate
- Condylar foramen
- Stylomastoid foramen
- Carotid canal
- Styloid process
- Zygomatic arch
- Mastoid process
- Occipital condyle
- Mandibular fossa
- External occipital protuberance
What passes through the cribriform plate?
Olfactory nerve
What passes through the optic foramen?
Optic nerve
Opthalmic artery
What passes through the superior orbital fissure?
Occulomotor nerve
Trochlear nerve
Opthalmic division (V1)
Abducens nerve
Opthalmic veins
What passes through the foramen rotundum?
Maxillary division (V2)
What passes through the foramen ovale?
Mandibular division (V3)
What passes through the foramen spinosum?
MMA
MMV
What passes through the foramen lacerum?
Greater petrosal nerve
What passes through the carotid canal?
ICA
What passes through the internal acoustic meatus?
Facial
Vestibulocochlear
Labyrinth artery
What passes through the jugular foramen?
Glossopharyngeal (IX)
Vagus (X)
Accessory (XI)
IJV
Posterior meningeal artery
What passes through the hypoglossal foramen?
Hypoglossal nerve
What passes through the foramen magnum?
Spinal cord
Vertebral arteries
Anterior spinal artery
Posterior spinal artery
Spinal part of accessory nerve (XI)
Between what layers are venous sinuses located?
The inner and outer layers of the dura
What vessel forms the groove that starts lateral to the foramen spinosum??
Middle Meningeal artery
What is significant about the course of the MMA?
It travels across the inner surface of the pterion
This makes it vunerable to damage from a blow to the head as the pterion is very weak
What is shown here?
Internal occipital protuberance
What structure makes this groove?
Transverse venous sinus
What forms this groove?
Sigmoid sinus
What does the sigmoid sinus drain into?
The IJV through the jugular foramen
What is this?
Sella turcica - “Turkish saddle”
A deep depression in the midline in the middle cranial fossa that houses the pituitary
Which bone is the sella turcica found in?
Sphenoid
What is shown here
Anterior clinoid process
What is shown here?
Posterior clinoid process
What do the anterior and posterior clinoid processes attach?
Tentorum cerebelli
What is housed in the groove either side of the sella turcica?
The cavernous sinus
What passes through the cavernous sinus to reach the superior orbital fissure?
All the structures that leave through the superior orbital fissure
What is shown here?
Pterygoid plates
What muscles attach to the lateral pterygoid plate?
Pterygoid muscles
What muscles attach to the medial pterygoid plate?
Superior constrictor
