(21) Skull Anatomy

Vocabulary based flashcards covering the anterior, lateral, and internal structures of the human skull, including cranial fossae and foramina.

Supraorbital margin

The upper edge of the orbit formed by the frontal bone.

Supraorbital notch/foramen

An opening that transmits the supraorbital nerve (a branch of $CN\,V_1$) and vessels.

Supraorbital nerve

A branch of $CN\,V_1$ transmitted via the supraorbital notch or foramen.

Infraorbital foramen

An opening in the maxilla that transmits the infraorbital nerve (a branch of $CN\,V_2$) and vessels.

Infraorbital nerve

A branch of $CN\,V_2$ transmitted via the infraorbital foramen.

Lateral boundary of the orbit

Formed by the zygomatic and frontal bones.

Inferior boundary of the orbit

Formed by the maxilla and zygomatic bones.

Medial boundary of the orbit

Formed by the maxilla, lacrimal, and frontal bones.

Frontal bone (orbit)

One of the six bones that form the orbit; also forms the supraorbital margin and part of the medial and lateral boundaries.

Ethmoid bone (orbit)

One of the bones located within the orbit.

Sphenoid bone (orbit)

A bone that contributes to the orbit and contains the superior orbital fissure and optic canal.

Lacrimal bone (orbit)

A bone within the orbit that contributes to the medial boundary.

Maxilla (orbit)

A bone within the orbit that forms part of the inferior and medial boundaries.

Zygomatic bone (orbit)

A bone within the orbit that forms part of the lateral and inferior boundaries.

Superior orbital fissure

An opening of the orbit located between the greater and lesser wings of the sphenoid bone.

Inferior orbital fissure

An opening located in the floor of the orbit.

Optic canal

An opening of the orbit that transmits the optic nerve ($CN\,II$) and the ophthalmic artery.

Zygomatic bone

Often called the cheek bone, it articulates with the maxilla, frontal, and temporal bones.

Zygomatic arch

Formed by the lateral articulation of the zygomatic bone with the temporal bone.

Nasal septum (anterior)

The forward portion of the bridge dividing the nostrils, composed of cartilage.

Nasal septum (posterior)

The back portion of the nasal bridge, composed of the ethmoid and vomer bones.

Piriform aperture

The anterior opening of the nasal cavity.

Body of the maxilla

The central part of the maxilla which contains the maxillary sinus.

Zygomatic process (maxilla)

The portion of the maxilla that articulates with the zygomatic bone.

Frontal process (maxilla)

The portion of the maxilla that extends upward to articulate with the frontal bone.

Palatine process

The horizontal process of the maxilla.

Alveolar process (maxilla)

The ridge of the maxilla that contains the sockets for the teeth.

Body of the mandible

The horizontal part of the lower jaw containing the mental foramen.

Mental foramen

An opening in the body of the mandible that transmits the mental nerve.

Mental nerve

A branch of $CN\,V_3$ that passes through the mental foramen.

Angle of the mandible

The corner where the body of the mandible meets the ramus.

Ramus of the mandible

The vertical portion of the mandible that extends upward from the angle.

Coronoid process

The anterior process located on the superior part of the mandibular ramus.

Condylar process

The posterior process on the superior part of the mandibular ramus that articulates with the skull.

Zygomatic process (temporal bone)

Joins with the temporal process of the zygomatic bone to form the zygomatic arch.

External acoustic (auditory) meatus

The canal in the temporal bone leading to the eardrum.

Styloid process

A slender projection of bone from the temporal bone.

Mastoid process

A prominent projection of the temporal bone located behind the ear.

Sagittal suture

The joint located between the two parietal bones.

Coronal suture

The joint between the frontal bone and the two parietal bones.

Lambdoid suture

The joint between the occipital bone and the two parietal bones.

Squamous suture

The joint between the two parietal bones and the two temporal bones.

Pterion

The landmark where the sphenoid, frontal, parietal, and temporal bones all come together.

Middle meningeal artery

An artery located in the epidural space, for which the pterion is an important landmark.

Epidural space

The space underlying the pterion where the middle meningeal artery is located.

Anterior Cranial Fossa (neuroanatomy)

The cranial compartment that contains the frontal lobes (frontal poles) of the cerebral hemispheres.

Anterior Cranial Fossa (boundaries)

Formed by the frontal bone in front and the lesser wings of the sphenoid bone behind.

Crista galli

A median ridge of the ethmoid bone that divides the anterior cranial fossa medially.

Cribriform plates

Structures of the ethmoid bone that contain small openings for the olfactory nerves.

Anterior Cranial Fossa (floor)

This structure forms the roofs of the orbits.

Olfactory nerves

Structure transmitted through the cribriform plate in the anterior cranial fossa.

Middle Cranial Fossa (neuroanatomy)

The cranial compartment that contains the anterior parts of the temporal lobes.

Middle Cranial Fossa (boundaries)

Formed by the greater wings of the sphenoid bone in front and the temporal bone behind.

Sella turcica

The "Turkish saddle" located on the upper part of the sphenoid body which contains the pituitary gland.

Pituitary gland

The endocrine gland located within the sella turcica.

Petrous part of the temporal bone

Form of the middle cranial fossa floor that roofs the chambers of the middle and inner ear.

Basilar skull fractures

A type of injury for which the middle cranial fossa is a common site.

Optic nerve ($CN\,II$)

A nerve transmitted through the optic canal in the middle cranial fossa.

Ophthalmic artery

An artery transmitted through the optic canal alongside $CN\,II$.

Oculomotor nerve ($CN\,III$)

One of the nerves transmitted through the superior orbital fissure.

Trochlear nerve ($CN\,IV$)

One of the nerves transmitted through the superior orbital fissure.

Ophthalmic division of the trigeminal nerve ($CN\,V_1$)

One of the divisions of the trigeminal nerve transmitted through the superior orbital fissure.

Abducens nerve ($CN\,VI$)

One of the nerves transmitted through the superior orbital fissure.

Carotid groove

A groove in the middle cranial fossa that contains the internal carotid artery.

Foramen rotundum

An opening in the middle cranial fossa that transmits the maxillary division of the trigeminal nerve ($CN\,V_2$).

Foramen ovale

An opening in the middle cranial fossa that transmits the mandibular division of the trigeminal nerve ($CN\,V_3$).

Foramen spinosum

An opening in the middle cranial fossa that transmits the middle meningeal artery.

Epidural hematoma

A condition produced when the middle meningeal artery is torn during a temporal bone fracture.

Foramen lacerum

A cranial opening filled by cartilage in a living person but absent in a dried skull.

Posterior Cranial Fossa (neuroanatomy)

The cranial compartment containing the cerebellum, pons, and medulla.

Posterior Cranial Fossa (boundaries)

Formed by the temporal and sphenoid bones in front and the occipital bone behind.

Foramen magnum (division)

The large opening that medially divides the posterior cranial fossa.

Dural venous sinuses (fossae)

Structures that groove the floor and posterior walls of the posterior cranial fossa.

Internal acoustic (auditory) meatus

An opening in the posterior cranial fossa that transmits $CN\,VII$ and $CN\,VIII$.

Facial nerve ($CN\,VII$)

One of the nerves transmitted through the internal acoustic meatus.

Vestibulocochlear nerve ($CN\,VIII$)

One of the nerves transmitted through the internal acoustic meatus.

Foramen magnum (juncture)

The site of the juncture of the medulla with the spinal cord.

Spinal roots of accessory nerve ($CN\,XI$)

Nerves transmitted through the foramen magnum.

Spinal and vertebral arteries

Vessels transmitted through the foramen magnum.

Jugular foramen

Transmits the sigmoid sinus/internal jugular vein and cranial nerves $CN\,IX$, $CN\,X$, and $CN\,XI$.

Hypoglossal canal

An opening in the posterior cranial fossa that transmits the hypoglossal nerve ($CN\,XII$).