Craniofacial Vasculature Flashcards
What thin area of bone on the skull serves as a landmark overlying the midle meningeal a.?
Pterion
The pterion serves as a landmark overlying what major artery that can cause intracranial bleeding if head trauma occurs?
What muscle provides some protection of this area?
Middle meningeal a.
Some protection from temporalis m.
_____ ____ = 3 dense regular CT layers that separate the soft tissue of the brain from the bones of the cranium
Cranial meninges
Functions of cranial meninges
Enclose and protect blood vessels that supply the brain
Contain and circulate CSF
Form dural venous sinuses that drain blood from brain
Provide cushion and protection to brain
Cranial meninges from superficial to deep
Dura mater
Arachnoid mater
Pia mater
What 3 areas are drained by the dural venous sinuses?
Compartments containing CSF
Blood from brain
Blood from superficial face
Dura mater is a tough membrane composed of 2 fibrous layers. It is the strongest of the meninges. What are the 2 layers it is composed of?
Periosteal layer: more superficial, attaches to periosteum of cranial bones
Meningeal layer: lies deep to periosteal layer
The meningeal layer of dura mater is usually fused to the periosteal layer, except in specific areas where the two layers separate to form large, blood-filled spaces called _____
Dural venous sinuses
Arachnoid mater lies immediately internal to dura mater. It is partially composed of a delicate web of collagen and elastic fibers, termed the _____ ____
Arachnoid trabeculae
Between the arachnoid mater and overlying dura mater is the _____ ____
Immediately deep to the arachnoid is the ______ _____
Subdural space
Subarachnoid space
Thin layer of delicate CT that tightly adheres to brain and follows every contour of the brain surface
Pia mater
The meningeal layer of the dura mater extends as flat partitions deep into the cranial cavity at 4 locations called ____ ____ ___
Cranial dural septa
Membranous partitions separate specific parts of the brain and provide additional stabilization and support to the entire brain. What are the 4 primary membranous partitions?
Falx cerebri
Tentorium cerebelli
Falx cerebelli
Diaphragma sellae
In the septa are dural venous sinuses — what are some examples of these?
Superior and inferior sagittal sinuses
Straight sinus
Sigmoid sinus
Transverse sinus
What cranial dural septum separates the cerebrum from the cerebellum inferiorly?
Tentorium cerebelli
What cranial dural septum separates the hemispheres of the cerebellum at its isthmus?
Falx cerebelli
What cranial dural septum divides the two hemispheres of the brain?
Falx cerebri
What nerves provide innervation to the meninges?
Opthalmic nerve (CN V1)
Maxillary nerve (CN V2)
Mandibular nerve (CN V3)
Cervical spinal nerves (C2,C3) [distributed by CN XII and CN X]
Also meningeal branches of ethmoidal nerve
Drainage of superficial facial structures via the orbit occurs by way of what veins?
Superior and inferior opthalmic vein
What large dural venous sinus exists in close relation with the sella turcica?
Cavernous venous sinus
What nerves are in close proximity to the cavernous sinus and may be impinged in the case of a venous thrombus?
CN III
CN IV
CN V (1,2,3)
CN VI
Primary arterial supply to meninges
Middle meningeal a. (Anterior, middle, and posterior branches)
The middle meningeal a. arises from what artery?
Maxillary a. (Which branches from the external carotid a.)
The middle meningeal a. supplies the meninges after passing through what opening in the skull?
Foramen spinosum
CSF is a clear, colorless liquid that circulates in the _____ of the brain and the _____ space
Ventricles; subarachnoid
Important functions of CSF
Buoyancy
Protection
Environmental stability
CSF is formed by the _____ ____ in each ventricle, produced by secretion of a fluid from the _____ cells that originate from blood plasma
Choroid plexus; ependymal
CSF is similar to blood plasma but has greater amounts of what 3 ions?
Sodium
Hydrogen
Calcium
CSF is similar to blood plasma but has greater amounts of sodium, hydrogen, and calcium. It has less _____
Potassium
Drainage of CSF to DV sinuses occurs via _____ _____ which are outpocketings of arachnnoid mater within the dural venous sinsuses
Arachnoid granulations
The bulk of the venous drainage from the head and neck terminate in the _______ vein, which joins the subclavian vein to form the _______ vein posterior to the medial end of the clavicle
Internal jugular; brachiocephalic
Primary venous drainage of neck to thorax occurs via what vein?
Left brachiocephalic
Six levels of cervical lymph nodes
I = submental and submandibular
II-IV = deep cervical LNs distributed along IJV (upper lateral, middle lateral, and lower lateral groups)
V = posterior cervical triangle
VI = anterior cervical LNs
[so I, V, and VI are considered superficial LNs]
T/F: the superficial LNs of the head and neck receive lymph from the scalp, face, and neck. They are arranged in a ring shape, extending from inferior chin to posterior aspect of the head. They ultimately drain into deep LNs
True
The deep cervical lymph nodes can be divided into what 2 groups?
Superior and inferior deep cervical LNs
What are the 2 main sites in the neck where the cervical lymphatic pathways intersect?
Jugulofacial venous junction
Jugulosubclavian venous junction
Lymphatics from the head pass obliquely downward to this site, where the lymph is redirected vertically downward in the neck
Jugulofacial venous junction
The main lymphatic trunk, the thoracic duct, terminates at this location, where lymph collected for the left side of the head and neck region is comingled with lymph draining from the rest of the body
Jugulosubclavian venous junction
What is the difference in potential pathology if only peripheral nodal groups are affected vs. central groups (e.g., those at the venous junctions) in the cervical region?
Peripheral nodal groups suggest localized disease process
Central groups usually signify extensive disease process
Central lymph nodes can be obtained from diagnostic evaluation by ________ biopsy
Prescalene
The internal jugular vein receives blood from the brain, face, and neck. It emerges through the ____ ____ as a continuation of the _____ sinus, and descends posteriorly then lateral to the ________ _____ artery inside the carotid sheath
Jugular foramen; sigmoid; internal carotid
T/F: valves are not found in the internal jugular vein
False: valves are variably present in the IJV, defending against retrograde flow when coughing, etc.
What are the superior and inferior bulbs of the IJV?
Dilatations near the origin and termination of the vein
The inferior petrosal sinus assists in draining the ________ sinus
It leaves through the anterior part of the _______ foramen, joining the IJV below the superior bulb
Cavernous
Jugular
The _______ vein is formed by the union of superficial temporal and maxillary vein from the pterygoid plexus
Retromandibular
The retromandibular vein passes inferiorly in the substance of the ______ gland, emerging from its lower border and divides into 2 parts
Parotid
The anterior division of the retromandibular vein joins the _____ vein
The posterior division of the retromandibular vein pierces the deep fascia and joins the posterior auricular v. to form the _____ _____ v., eventually emptying into the _________v.
Facial
External jugular; subclavian
What vein communicates with the cavernous sinus via the superior and inferior ophtalmic veins?
Angular v.
Initial tributaries of angular v.
Supra-orbital v.
Supratrochlear v.
What vein commences lateral to the root of the nose, descending onto the face posterior to the corresponding artery, following along to the lower border of the mandible?
Facial vein