Cranial cavity Flashcards
What is the bregma?
Meeting point of the coronal and sagittal sutures
What is the lambda?
Meeting point of the sagittal and lamdoid sutures
What are the granular foveole?
Pits on either side of the sagittal sulcus that house arachnoid granulations
What is the Pterion?
Thinnest part of the lateral wall of the skull
Marks the junction between the parietal, temporal, sphenoid, and frontal bones
What can occur with an injury over the pterion?
Epidural hemorrhage
Related to middle meningeal artery and vein
What are emissary veins?
Valveless veins that pass through skulll bones connecting the veins of the scalp to the venous sinuses inside the cranial cavity
What is the dangerous area of the scalp?
4th layer of loose CT
What are the 3 cranial fossae and there separations?
Anterior cranial fossa
Separation - lesser wing of sphenoid
Middle cranial fossa
Separation - petrous part of temporal bone
Posterior cranial fossa
What is the cristal galli?
Sharp upward projection of ethmoid bone in the anterior cranial fossa
Site of attachment for falx cerebri
Where does the olfactory nerve leave the cranial cavity?
Cribriform plate of ethmoid bone
What structures pass through the optic canal?
Optic N
Ophthalmic A branch of ICA
What structures pass through the superior orbital fissure?
Oculomotor N
Trochlear N
CN V1 - ophthalmic division of trigeminal N
Abducens N
Superior ophthalmic vein
What does the superior ophthalmic vein drain into?
Cavernous sinus
What passes through the foramen rotundum?
Maxillary branch of trigeminal N (CN V2)
What passes through the foramen ovale?
Mandibular branch of trigeminal N (CN V3)
What passes through the foramen spinosum?
Middle meningeal A
What is the sella turcica?
Hypophysial fossa
Accommodates pituitary gland
On sphenoid bone
What structures pass through the foramen magnum?
Medulla oblongata
Meninges
Vertebral A
Spinal roots of spinal accessory nerves
Where does the hypoglossal N leave the cranial cavity?
Hypoglossal N - CN XII
What structures pass through the jugular foramen?
Glossopharyngeal N
Vagus N
Spinal accessory N
Sigmoid and inferior petrosal sinuses
What structures pass through the internal acoustic meatus?
Facial N
Vestibulocochlear N
Labyrinthine A
What is scaphocephaly?
Premature fusion of sagittal suture
What is brachycephaly?
Premature fusion of the coronal and lamboidal sutures
What is plagiocephaly?
Premature fusion of the coronal and lambdoid sutures on one side of the skull
What will prevent fontanelles from fusing?
Vit D deficiency
When should the anterior fontanelle close by?
18 months
When should the posterior fontanelle close by?
1 year old
What are the layers of dura mater?
Endosteal layer - outer
Meningeal layer - inner
What is a characteristic of arachnoid mater?
Avascular
What are the dural folds?
Falx cerebri
Falx cerebelli
Tentorium cerebelli
Diaphragm sellae
What is the location of the cavernous sinus?
Either side of sella turcica
What are the tributaries of the cavernous sinus?
Superior ophthalmic V
Inferior ophthalmic V
Central V of retina
Sphenoparietal sinus
What does the cavernous sinus drain into?
Petrosal sinus to internal jugular V
What structures pass through the cavernous sinus?
Oculomotor N
Trochlear N
Ophthalmic N
Maxillary N (V2)
Abducent N
ICA
How can a tooth infection spread to the cavernous sinus?
Through pterygoid venous plexus
What artery is involved in an epidural hemorrhage?
Anterior branch of middle meningeal A
What is the characteristic shape of epidural hemorrhage?
Elliptical in shape and hyperdense
What type of hemorrhage can cross the midline?
Epidural hemorrhage
What artery is involved in a intracerebral hemorrhage?
Middle cerebral A
What are three things that can caused communicating hydrocephalus?
Arachnoiditis
Choroid plexus papilloma
Subarachnoid hemorrhage
What is filum terminale?
Delicate, glistening thread-like structure that extends from conus medullaris to first coccygeal vertebra
What are the two parts of the filum terminale?
Externum - outside dural sac - 5 cm
Internum - within dural sac - 15 cm
What structure is the filum terminale related to?
Pia mater
What is the subarachnoid septum?
Mid sagittal pial septum that connects dorsal surface of spinal cord with arachnoid mater
What is the linea splendens?
Pial septum into anterior medial fissure
What is the ligamentum denticulata?
Two transparent bands extending laterally between posterior and anterior nerve roots from pia mater that cover the cord
