Gross Anatomy Flashcards
Mandible
Largest and strongest none of face
Consists of body, rami, coronoid process (temporalis muscle), and condyle
Mandibular foramen
Located on medial side of ramus under the lingula
IA nerve, artery, and vein
Mental foramen
Located below second premolars
Mental nerve (skin and mucous membrane)
Incisive nerve (pulp chambers of anterior teeth)
Scalp
S: skin (epidermis, dermis) C: connective tissue (superficial fascia) A: aponeurosis L: loose connective tissue P: periosteum
Dura mater
Arachnoid
Subarachnoid space
Cerebrum
What attaches to the lingula?
The sphenomandibular ligament
Epidural space
Potential space between periosteum and dura mater
Contains middle meningeal artery
Epidural hematoma = middle meningeal
Dura mater
Membranous outermost meninge that forms venous sinuses
Endosteal layer on periosteum side
Meningeal layer on brain side
Subdural space
Between dura and arachnoid
Contains bridging veins and venous sinuses
Subdural hematoma= bridging vein
Arachnoid
Weblike lattices between dura and pia
Subarachnoid space
Between arachnoid and pia
Filled with CSF
Contains Circle of Willis
Space entered with lumbar puncture
Vertical dura mater folds
Falx cerebri: separates left and right cerebral hemispheres; contains superiors and inferior sagittal sinuses
Falx cerebelli: separates cerebellum; contains occipital sinus
Horizontal dura mater folds
Tentorium cerebelli: separates cerebrum from cerebellum; contains straight, transverse, and superior petrosal sinuses
Uncus: medial parahippocampal gyrus
Diaphragma sella: roof of sella turcica
Dural sinuses
Superior sagittal Inferior sagittal Straight sinus Cavernous sinus (2) Superior petrosal sinus (2) Inferior petrosal sinus (2) Occipital sinus Transverse sinus (2) Confluence of sinuses Sigmoid
Tributaries of dural sinuses
Emissary veins: drain scalp to dural sinuses
Diploic veins: drain diploe of skull to dural sinuses
Meningeal veins: drain meninges into dural sinuses
What major vessel drains the head and neck?
Internal jugular vein
Cavernous sinuses
Anterior: superior and inferior ophthalmic veins, pterygoid plexus
CNs 3, 6, V1, V2
Posterior: superior and inferior petrosal, intercavernous sinus
CN 6, ICA
What sinus connects the cavernous and sigmoid sinuses?
The superior petrosal sinus
Which nerve is the smallest and most medial in the cavernous sinus and will be the first affected by an infection or laterally expanding pituitary tumor?
CN VI
CV III and IV are also in this area
Pterygoid plexus of veins
Located in infratemporal fossa
Surrounds maxillary artery
Drains maxillary vein posteriorly and deep facial vein anteriorly (connects with anterior facial vein)
Ventricular system of brain
Ependymal cells line and produce CSF
Lateral ventricle near caudate nucleus
Inferior horn near hippocampus
Third ventricle near hypothalamus
Fourth ventricle near pons
Choroid plexus and ventricular system regulate intracranial pressure
CSF circulation
- Lateral ventricles
- Foramen of Monro
- Third ventricle
- Cerebral aqueduct
- Fourth ventricle
- Foramina of Magendie (medial) and Luschka (lateral)
- Bathes cisterns in subarachnoid space
- Arachnoid granulations into superior sagittal sinus to empty CSF into venous circulation
Where is CSF made?
Choroid plexus
Ependymal cells can also make CSF
Blood brain barrier
- Blood CSF barrier: tight junctions in choroid plexus epithelial cells allow selective passage
- Vascular endothelial barrier: tight junctions between endothelial cells
- arachnoid barrier: arachnoid cells form a barrier to present substances from dural vessel from diffusing toward brain
Circle of Willis
Posterior cerebral artery Posterior communicating artery Internal carotid artery Anterior cerebral artery Anterior communicating artery
2 vertebral arteries and 2 carotid arteries
What arteries supply medial aspect of frontal and parietal lobes?
Right and left internal carotid arteries
Branch to anterior cerebral artery and middle cerebral artery
What supplies occipital cortex?
Basilar artery (convergence of left and right vertebral arteries)
Branches to posterior cerebral artery
Does the internal carotid artery have branches in the neck?
No
Vertebral arteries branch off of what?
Subclavian arteries
Middle cerebral artery
Largest branch of the ICA
Causes the most ischemic injury if blocked
Leticulostriate arteries, branches of MCA, are often involved in stroke and are thin walked and can rupture
Tongue Innervation
Motor: CN XII
Damage to CN XII causes tongue to deviate to the side damaged
Sensation: CN V3, IX, X
Taste: CN VII, IX, X
Even though the anterior 2/3, posterior 2/3 of tongue and epiglottis have different Innervation (CN VII, CN IX, and CN X respectively), where do their pathways converge?
Solitary tract to nucleus of solitary tract (gustatory nucleus)
Thalamic nucleus (VPM)
Chorda tympani nerve
Part of CN VII
Solitary tract nucleus, superior salivatory nucleus
Arises from geniculate ganglion, emerges from petrotympanic fissure, crosses tympanic membrane and joins lingual nerve (V3)
Taste to anterior 2/3 of tongue
Preganglionic parasympathetic synapse in submandibular ganglion
Inferior surface of tongue
Lingual frenulum: vertical fold in midline
Plica fimbriata: fold of mucous membrane lateral to frenulum
Wharton’s and Rivian ducts: openings to submandibular and sublingual salivary glands
Types of tastebuds
Filiform: rough, avascular, no tastebuds, rough texture of tongue
Fungiform: mushroom shaped, contain tastebuds
Circumvallate: large circular structures with tastebuds
Foliate: lateral surface of tongue, nonfunctional
Muscles controlling the tongue
Bony attachments: genial tubercles, styloid process, and hyoid bone
Innervation of tongue muscles = CN XII (except palatoglossus)
Blood supply = lingual artery
Genioglossus muscle
O: genial tubercles
I: hyoid (inferior) and tongue (superior)
A: protrudes tongue
N: XII
Hyoglossus muscle
O: hyoid
I: side of tongue medial to styloglossus
A: depress tongue, pulls down side
N: XII
Styloglossus muscle
O: styloid process
I: side of tongue
A: pulls tongue up and back
N: XII
Palatoglossus muscle
O: anterior soft palate
I: side and dorsum of tongue
A: pulls tongue up and back
N: X
Intrinsic tongue muscles
Longitudinal: shorten tongue, make dorsum convex (inferior) or concave (superior)
Transversus: narrow and elongate tongue
Verticalis: flattens and broadens the tongue
Speaking sounds:
“La la”
“Mi mi”
“Kuh kuh”
CN XII moved tongue against roof of mouth
CN VII moves lips
CN X raises palate
Hyoglossus muscle relationships
Medial to = lingual artery
Lateral to = lingual vein, nerve, submandibular duct, hypoglossal nerve
Palate nerve, blood supply
Motor Innervation: pharyngeal plexus
Sensory Innervation: V2 (greater palatine posteriorly, nasopalatine anteriorly)
Blood supply: third part of maxillary artery (branch of ECA)
Palatial salivary glands
Mostly mucous
Located beneath mucous membrane if hard and soft palate
Hard palate components
Maxillary bone (palatine processes)
Palatine bones (horizontal plates)
Covered with keratinized mucosa
Palatial salivary glands beneath mucosa
Soft palate components
Muscles: palatopharyngeus, palatoglossus, levator veli palatini, tensor veli palatini; uvular
Covered by non-keratinized mucosa
Anterior zone of sub mucosa contains fat
Posterior zone contains mucous glands
Palatal aponeurosis: fibrous connective tissue over muscles
Soft palate attachments
To the tongue: palatoglossus arches (anterior pillar)
Palatoglossus draws tongue and soft palate together, narrows isthmus of fauces
To the pharynx: palatopharyngeal arches (posterior pillar)
Palatopharyngeus elevated pharynx, closes nasopharynx and aids in swallowing
Uvula
Suspended from soft palate
Bifid uvula from incomplete fusion of palatine shelves
Unilateral damage to pharyngeal plexus causes uvula to deviate contralaterally (pulled to functional side)
Fauces
Fauces are between anterior and posterior pillars
House the palatine tonsils
Tonsils
Pharyngeal: located on nasopharynx and do not have lymph, sinuses not crypts
Palatine: located in isthmus if fauces and contain crypts and lymphoid follicles, but no sinuses
Lingual: located in dorsum of tongue and contain lymphoid follicles each with a single crypt