Brain and Related Vasculature

Gross Anatomy


Gross Anatomy of the Brain and Related Vasculature



ASSIGNMENTS
Moore's Clinically Oriented Anatomy: 887-898

Grant's Dissector: None; A handout will be provided

Netter Atlas: Plates 99-103, 107-112, 130-137



HELPFUL HINTS
  1. Handle the brain carefully. If you use too much force when examining the lateral sulcus, you will fracture the temporal lobe.

  2. Locate the central sulcus first and use it as a major landmark for identification of the other features on the lateral surface of the brain.

  3. Be sure to correlate the surface features of the brain to the osseous features seen in the cranial cavity of the cadaver.

  4. Use the plastic brainstem models to see the brainstem features described in this exercise, then locate those features on the surface of the brainstem



WHEN YOU FINISH THIS SECTION, YOU SHOULD BE ABLE TO PERFORM THE FOLLOWING TASKS AND ANSWER THESE QUESTIONS
  1. What osseous structure(s) is(are) related to the frontal lobe of the brain? To the parietal lobe? To the occipital lobe? Make a chart that demonstrates the osseous relationships of all lobes listed in the outline below.

  2. Define gyrus. Define sulcus. How do these structures affect the surface area of the cerebral cortex?

  3. List the named gyri that you have studied to date. What is the primary function of each?

  4. Starting at the heart, trace a drop of blood to the cerebral arterial circle. Which of the vessels listed in the outline below carry blood to the cerebral cortex?

  5. Do the arteries that supply the cerebral cortex enter it from its superficial surface, its deep surface or both?

  6. Which vessels participate in the formation of the cerebral arterial circle? What would happen if one internal carotid artery were to become blocked?

  7. Is the middle meningeal artery a branch of the internal carotid artery or the external carotid artery?

  8. Name the veins that drain the cerebral cortex from its superior surface. Into which collecting vessel do these veins drain?

  9. List all venous structures encountered by a drop of blood that is passing from the great cerebral vein to the right atrium of the heart.

  10. What is contained within the ventricular system of the brain? How is this system related to the spinal cord and spinal meninges?

  11. List the parts of the brainstem.

  12. Make a list of the cranial nerves associated with the brainstem. Why are cranial nerves I and II not on your list?

  13. Describe the pattern of vascular suply to the brainstem.

  14. What would happen if a small artery to the brainstem were to become blocked?




PARTS OF THE BRAIN - NAMES AND LOCATION
SURFACE FEATURES OF THE BRAIN



FEATURES OF THE BRAIN SEEN ON MID-SAGITTAL SECTION
BLOOD SUPPLY TO THE BRAIN

ANATOMY TABLES FOR TODAY'S TOPIC

Parts of the Brain - An Overview

StructureDescriptionSignificance
forebrainalso known as: prosencephaloncomprised of: telencephalon or cerebral hemispheres and diencephalon; site of termination of cranial nerves I & II; contains lateral & third ventricles
midbrainalso known as: mesencephalonconnects forebrain & hindbrain; site of origin of cranial nerves III & IV; contains cerebral aqueduct
hindbrainalso known as: rhombencephaloncomprised of: metencephalon or pons & cerebellum and myelencephalon or medulla oblongata; site of origin for cranial nerves V-XII (except spinal part of accessory nerve); contains fourth ventricle
telencephalonrostral part of prosencephalon/forebraincomprised of: cerebral hemispheres & basal ganglia; contains lateral ventricles
diencephaloncaudal portion of prosencephalon/forebraincomprised of: thalamus, metathalamus, subthalamus, epithalmus; contains third ventricle
mesencephalonalso known as: midbraincontains the corpora quadrigemina
metencephalonrostral part of rhombencephaloncomprised of: pons & cerebellum
myelencephaloncaudal part of rhombencephaloncomprised of: medulla oblongata; medulla becomes continuous with the spinal cord at the level of the foramen magnum

Gross Features of the Brain - as Seen from a Lateral View

StructureDescriptionSignificance
cerebral hemispheresalso known as: telencephaloncomprised of: cortex featuring gyri, sulci, fissures & lobes; commisures connecting parts; basal ganglia; contains lateral ventricles; termination of the olfactory tract (cranial nerve I)
longitudinal fissuremidline, sagittal cleft separating the paired cerebral hemispheresalso known as: longitudinal sulcus; contains the falx cerebri
pole, frontal the most anterior part of the cerebral hemisphere frontal pole is part of the frontal lobe
pole, temporal the most anterior part of the temporal lobe
pole, occipital the most posterior part of the cerebral hemisphere occipital pole is part of the occipital lobe; composed of primary visual cortex
sulcus, central separates frontal and parietal lobesseparates the precentral gyrus (motor) from the postcentral gyrus (sensory)
lobe, frontal rostral to central sulcuscontains prefrontal (emotions, personality) & precentral (primary and secondary motor) areas
lobe, parietal separated from the frontal lobe by the central sulcus, separated from occipital lobe by line through parieto-occipital sulcuscontains the primary and secondary somatosensory areas
lobe, temporalseparated from the frontal lobe by the lateral sulcusprimarily concerned with hearing and memory/learning
lobe, occipitalposterior to an imaginary line through parieto-occipital sulcuscontains the primarary and secondary visual cortex
gyrus, precentral most caudal gyrus of the frontal lobe; it lies rostral to the central sulcuscontains the primary motor cortex
gyrus, postcentralmost rostral gyrus of the parietal lobe; it lies caudal to the central sulcuscontains the primary sensory cortex
gyrus, superior temporalgyrus between the lateral sulcus and the superior temporal sulcuscontains the primary auditory cortex
gyrus, middle temporal gyrus between the superior and inferior temporal sulci
gyrus, inferior temporal gyrus between the inferior temporal sulcus and the inferior margin of the temporal lobe
insulaportion of the cerebrum located deeply within the lateral sulcusalso known as the island of Reil
gyrus, straightgyrus located on the medial side of the olfactory tractalso known as: gyrus rectus
uncusportion of the cerebral cortex on the medial side of the parahippocampal gyrus and overlying the amygdala; located near the free edge of the tentorium cerebellicontains olfactory cortex
sulcus, longitudinalmidline, sagittal cleft separating the paired cerebral hemispheresalso known as: longitudinal fissure
sulcus, precentral the sulcus anterior to the precentral gyrus in conjunction with the central sulcus, it defines the precentral gyrus (motor)
sulcus, postcentral the sulcus posterior to the postcentral gyrus in conjunction with the central sulcus, it defines the postcentral gyrus (sensory)
sulcus, lateralseparates frontal lobe and temporal lobethe insula lies in the floor of this sulcus
sulcus, superior temporal sulcus between the superior and middle temporal gyri used to define the superior and middle temproal gyri
sulcus, inferior temporal sulcus between the middle and inferior temporal gyri used to define the middle and inferior temporal gyri
sulcus, parieto-occipitalsulcus between the parietal and occipital lobeslandmark used to define the borders of the parietal and occipital lobes when viewing the cerebral hemisphere from a medial perspective
notch, preoccipitala shallow notch in the inferior surface of the cortex (superior to the cerebellum) as seen in lateral viewa surface landmark for defining the border between the parietal and occipital lobes
brain stemcomprised of: midbrain, pons & medulla oblongataorigin of most of the cranial nerves
midbrainalso known as: mesencephalonconnects forebrain & hindbrain; the site of origin of cranial nerves III & IV; contains cerebral aqueduct
ponsanterior portion of the metencephalonthe site of origin of cranial nerves V, VI, VII & VIII; forms part of the anterior wall of the fourth ventricle
medulla oblongataalso known as: myelencephalon; most caudal portion of the brainstemit is continuous with the spinal cord at the foramen magnum; upper portion forms the floor of the fourth ventricle; the site of origin for cranial nerves VIII, IX, X, XI (cranial root), & XII

Gross Features of the Brain - as Seen from an Inferior View

StructureDescriptionSignificance
cerebral hemispheresalso known as: telencephaloncomprised of: cortex featuring gyri, sulci, fissures & lobes; commisures connecting parts; basal ganglia; contains lateral ventricles; termination of the olfactory tract (cranial nerve I)
longitudinal fissuremidline, sagittal cleft separating the paired cerebral hemispheresalso known as: longitudinal sulcus
pole, frontal the most anterior part of the cerebral hemisphere frontal pole is part of the frontal lobe
pole, temporal the most anterior part of the temporal lobe
pole, occipital the most posterior part of the cerebral hemisphere occipital pole is part of the occipital lobe; composed of primary visual cortex
lobe, frontal rostral to central sulcuscontains prefrontal (emotions, personality) & precentral (primary motor) areas
lobe, temporalseparated from the frontal lobe by the lateral sulcusprimarily concerned with hearing and memory/learning
lobe, occipitalposterior to an imaginary line through parieto-occipital sulcuscontains the primarily visual cortex
lobe, limbicstructures on the medial surface of the cerebral hemisphere which surround the rostral brainstem; includes the subcallosal gyrus, cingulate gyrus and parahippocampal gyrusprimarily concerned with emotions and memory
gyrus, parahippocampalgyrus on the inferior surface of the temporal lobe that lies lateral to the midbrainthe uncus is a medial projection of the parahippocampal gyrus
gyrus, straightgyrus located on the medial side of the olfactory tractalso known as: gyrus rectus
gyrus, lingualgyrus lying inferior to the calcarine sulcuscontains primary visual cortex
uncusportion of the cerebral cortex on the medial side of the parahippocampal gyrus and overlying the amygdala; located near the free edge of the tentorium cerebellicontains olfactory cortex
apex of cuneusportion of the cuneus seen in an inferior view of the cerebral hemispherecontains part of the visual cortex
sulcus, longitudinalmidline, sagittal cleft separating the paired cerebral hemispheresalso known as: longitudinal fissure
sulcus, olfactorysulcus that defines the lateral margin of the straight gyruscontains the olfactory bulb and tract
mamillary bodypart of the hypothalamus; a small spherical projection on the inferior surface of the floor of the third ventricle posterior to the hypophysisinvolved with memory and learning
brain stemcomprised of: midbrain, pons & medulla oblongataorigin of most of the cranial nerves
midbrainalso known as: mesencephalonconnects forebrain & hindbrain; the site of origin of cranial nerves III & IV; contains cerebral aqueduct
ponsanterior portion of the metencephalonthe site of origin of cranial nerves V, VI, VII & VIII; forms part of the anterior wall of the fourth ventricle
medulla oblongataalso known as: myelencephalon; most caudal portion of the brainstemit is continuous with the spinal cord at the foramen magnum; upper portion forms the floor of the fourth ventricle; the site of origin for cranial nerves VIII, IX, X, XI (cranial root), & XII
olfactory bulbflattened, oval enlargment at the anterior tip of the olfactory tractcontains the olfactory mitral cells which are the origin of the axons that course through the olfactory tract; the olfactory nerve begins at the bipolar olfactory cells in the nasal mucosa and courses through the cribriform plate to the olfactory bulb
olfactory tractribbon-like nerve tract that courses from the olfactory bulb to the cerebral cortex; it courses in the olfactory sulcuscarries the sense of smell
optic chiasmcrossover point for the nasal fibers of both retinaslateral visual fields (medial retinal fibers) project to the contralateral occipital lobe
hypophysismidline projection of neural and endocrine tissue attached to the floor of the diencephalonalso known as: pituitary gland

Gross Features of the Brain - as Seen in Mid-Sagittal View

StructureDescriptionSignificance
cerebral hemispheresalso known as: telencephaloncomprised of: cortex featuring gyri, sulci, fissures & lobes; commisures connecting parts; basal ganglia; contains lateral ventricles; termination of the olfactory tract (cranial nerve I)
longitudinal fissuremidline, sagittal cleft separating the paired cerebral hemispheresalso known as: longitudinal sulcus; contains the falx cerebri
lobe, frontal rostral to central sulcuscontains prefrontal (emotions, personality) & precentral (primary motor) areas
lobe, parietal separated from the frontal lobe by the central sulcus, separated from occipital lobe by line through parieto-occipital sulcuscontains the primary and secondary somatosensory areas
lobe, occipitalposterior to line through parieto-occipital sulcuscontains the primary and secondary visual cortex
lobe, limbica border (limbus = Latin for border) of cortical tissue surrounding the third ventricle; comprised of: cingulate gyrus, parahippocampal gyrus, uncus and other small portions of the adjacent cortexpart of the brain responsible for behavior and emotions
gyrus, cingulate the portion of the limbic lobe that lies superior to the corpus callosum cingulate gyrus is bounded by the callosal sulcus and the cingulate sulcus
gyrus, straightgyrus located on the medial side of the olfactory tractalso known as: gyrus rectus
gyrus, lingualthe portion of the occipital lobe that lies inferior to the calcarine sulcuscortical projection of the upper half of the contralateral visual field
sulcus, cingulatethe sulcus that lies superior to the cingulate gyrus
sulcus, centralseparates the frontal lobe from the parietal lobe; separates sensory cortex from motor cortexalso known as: fissure of Rolando
sulcus, parieto-occipitalsulcus on the medial surface of the cerebral hemisphere that lies between the precuneus and the cuneusforms the boundary between the parietal lobe and the occipital lobe
sulcus, calcarinesulcus between the lingual gyrus and the cuneusprimary visual cortex is both superior and inferior to it
cuneuspart of the cerebral cortex that forms the upper wall of the calcarine fissurecortical projection of the lower half of the contralateral visual field
pineal glandalso known as: pineal bodyrepresents an endocrine gland attached to diencephalon
corpus callosummidline part of great cerebral commissureconnects paired cerebral hemispheres
commisure, anteriora bundle of association fibers located anterior to the third ventricleconnections between the left and right temporal lobes
commisure, posteriora bundle of association fibers located posterior to the third ventricle, just inferior to the pineal glandconnections between various areas of the right and left sides of the midbrain
optic chiasmcrossover point for the nasal fibers of both retinaslateral visual fields (medial retinal fibers) project to the contralateral occipital lobe
thalamusan egg-shaped collection of nuclei forming part of the lateral wall of the third ventricledistributes information to appropriate areas of the cerebral cortex
hypothalamusa collection on nuclei forming the anterior portion of the lateral wall of the third ventriclecontrols visceral activity and elicits phenomena associated with the emotions
body of fornixa group of nerve cell fibers arching beneath the corpus callosummain efferent fiber system of the hippocampal formation
hypophysismidline projection of neural and endocrine tissue attached to the floor of the diencephalonalso known as: pituitary gland
brain stemcomprised of: midbrain, pons & medulla oblongataorigin of most of the cranial nerves
midbrainalso known as: mesencephalonconnects forebrain & hindbrain; the site of origin of cranial nerves III & IV; contains cerebral aqueduct
ponsanterior portion of the metencephalonthe site of origin of cranial nerves V, VI, VII & VIII; forms part of the anterior wall of the fourth ventricle
medulla oblongataalso known as: myelencephalon; most caudal portion of the brainstemit is continuous with the spinal cord at the foramen magnum; upper portion forms the floor of the fourth ventricle; the site of origin for cranial nerves VIII, IX, X, XI (cranial root), & XII
cerebellumposterior part of metencephalonlargest part of hindbrain; important for coordination of movement

Gross Features of the Brainstem - General

StructureDescriptionSignificance
midbrainalso known as: mesencephalonconnects forebrain & hindbrain; site of origin of cranial nerves III & IV; contains cerebral aqueduct
ponsanterior portion of metencephalonsite of origin of cranial nerves V, VI, VII & VIII; forms part of the anterior wall of the fourth ventricle
medulla oblongataalso known as: myelencephalon; most caudal portion of brainstemcontinuous with the spinal cord at the foramen magnum; upper portion forms the floor of the fourth ventricle; site of origin for cranial nerves IX, X, XI (cranial root), & XII


Surface Features of the Brainstem

StructureDescriptionSignificance
midbrain
CN II (optic)the portion of the visual pathway between the retina and the optic chiasm; it passes through the optic canal to enter the cranial cavityvision
optic tractthe portion of the visual pathway between the optic chiasm and the brainvision
optic chiasmcrossover point for the nasal fibers of both retinaslateral visual fields (medial retinal fibers) project to the contralateral occipital lobe
infundibulummidline stalk of the pituitary gland attached to the floor of the diencephaloninvolved in regulating hormone release from the anterior pituitary
StructureDescriptionSignificance
cerebral pedunclelargest part of midbrain; also known as: crus cerebriconnects forebrain with hindbrain; contains axons that control voluntary movement
CN III (oculomotor)emerges from the ventral surface of the brainstem near the midline at the caudal end of the midbrain; courses through the lateral wall of the cavernous sinus and exits the middle cranial fossa by passing through the superior orbital fissuremotor supply to skeletal mm.: levator palpebrae superioris, superior rectus, medial rectus, inferior rectus, inferior oblique; preganglionic parasympathetic to ciliary ganglion, postganglionic parasympathetic via short ciliary nn.to: ciliary m. & sphincter pupillae m.
superior colliculuselevation of midbrain tectum; pairedpart of corpora quadrigemina; important for reflex movements of eye, head & neck
StructureDescriptionSignificance
inferior colliculuselevation of midbrain tectum; pairedpart of corpora quadrigemina; important for auditory reflexes
CN IV (trochlear)emerges from the dorsal surface of the midbrain near the midline, just caudal to the inferior colliculus; courses through the lateral wall of the cavernous sinus and exits the middle cranial fossa by passing through the superior orbital fissuremotor supply for the superior oblique muscle of the eye; only cranial nerve to cross the midline of the brainstem - this crossover happens inside of the brainstem
pons
cerebellar peduncle, middleconnects cerebellum to pons
CN V (trigeminal)large sensory nerve arising from the ventral surface of the pons, also contains a motor component; courses to the middle cranial fossa where it separates into three divisions at the trigeminal ganglion: ophthalmic division passes out of cranial cavity by passing through superior orbital fissure, maxillary division passes through foramen rotundum, mandibular division passes through foramen ovale; ophthalmic and maxillary divisions course through the lateral wall of the cavernous sinusmotor to the muscles of branchial arch origin: temporalis, masseter, lateral & medial pterygoid, anterior belly of digastric, mylohyoid, tensor veli palatini, tensor tympani; three divisions supply sensory innervation the to skin of the face, mucosa of the nasal & oral cavities, mucosa of the anterior 2/3rds of tongue (general sense only)
StructureDescriptionSignificance
CN VI (abducens)small cranial nerve arising from the caudal end of the pons; emerges from the junction of the pons and medulla; courses anteriorly through the cavernous sinus lateral to the internal carotid artery, then exits the middle cranial fossa by passing through the superior orbital fissuremotor innervation of the lateral rectus muscle of the eye
CN VII (facial)cranial nerve arising from the caudal end of the pons; emerges from the junction of the pons and medulla just lateral to the abducens nerve; courses laterally to exit the posterior cranial fossa by entering the internal acoustic meatusmotor to muscles of facial expression; special sensory (taste) to anterior 2/3 of the tongue; secretomotor (parasympathetic) to: lacrimal, submandibular, sublingual, and mucous glands of nasal & oral cavities
CN VIII (vestibulocochlear)cranial nerve arising from the caudal end of the pons; emerges from the junction of the pons and medulla just lateral to the facial nerve; courses laterally to exit the posterior cranial fossa by entering the internal acoustic meatus; divides within the temporal bone into vestibular and cochlear partsvestibular portion: balance/proprioception; cochlear portion: hearing
StructureDescriptionSignificance
medulla oblongata
anterior median fissuremidline fissure on anterior surface of spinal cord & medullacontinuous with the anterior median fissure of the spinal cord; anterior spinal artery courses on the superficial surface of the spinal cord in this fissure
olivespaired elevations lateral to pyramids of medullacontain the inferior olivary nuclei
pyramidspaired paramedian elevations on anterior surface of medulla; separated by anterior median fissurecontain pyramidal tracts
pyramidal decussationpoint of crossover of 80% the fibers of the corticospinal tracts; located at lower levels of the medullavoluntary muscles of one side of the body are under the control of the contralateral cerebral cortex
StructureDescriptionSignificance
CN IX (glossopharyngeal)cranial nerve emerging from the rostral end of the ventral surface of the medulla lateral to the olive; it emerges rostral to the vagus nerve and caudal to the vestibulocochlear nerve; it courses inferiorly to exit the posterior cranial fossa by passing through the jugular foramen in company with the vagus and accessory nn.motor to the stylopharyngeus m.; secretomotor to the parotid gland (preganglionic parasympathetic via lesser petrosal n. to otic ganglion, postganglionic parasympathetic via auriculotemporal n.); taste to posterior 1/3 of the tongue; sensory to middle ear and auditory tube
CN X (vagus)cranial nerve emerging from the ventral surface of the medulla lateral to the olive and just caudal to the glossopharyngeal nerve; it courses inferiorly to exit the posterior cranial fossa by passing through the jugular foramen in company with the glossopharyngeal and accessory nn.the primary parasympathetic nerve to the organs of the neck, thorax and abdomen; motor supply to intrinsic muscles of the larynx, pharynx (except stylopharyngeus), and palate (except tensor veli palatini); brings back visceral sensations from the thoracic and abdominal organs
StructureDescriptionSignificance
CN XI (accessory)cranial nerve emerging from the ventral surface of the medulla lateral and inferior to the olive and just caudal to the vagus nerve and from the ventral surface of the cervical spinal cord; its cranial root joins the vagus nerve; its spinal root arises from upper levels of the cervical spinal cord and courses superiorly to enter the posterior cranial cavity by passing through the foramen magnum; the spinal portion courses inferiorly to exit the posterior cranial fossa by passing through the jugular foramen in company with the glossopharyngeal and vagus nn.motor innervation to the sternocleidomastoid and trapezius mm.
CN XII (hypoglossal)cranial nerve arising from the ventral surface of the medulla in the sulcus between the pyramid and the olive; it courses anteriorly to exit the posterior cranial fossa by passing through the hypoglossal canalmotor innervation of the intrinsic and extrinsic muscles of the tongue
posterior median sulcusmidline furrow on posterior surface of spinal cord and medullastarts at the obex and is continuous with the dorsal median sulcus of the spinal cord
StructureDescriptionSignificance


Surface Features of the Brainstem as seen on Mid-sagittal View

StructureDescriptionSignificance
midbrain
tectumthe roof of the midbrain, formed by the superior and inferior colliculi; located dorsal to the cerebral aqueductalso known as: quadrigeminal plate
superior colliculuspaired elevations of midbrain tectumpart of corpora quadrigemina; important for reflex movements of eye, head & neck
inferior colliculuspaired elevations of midbrain tectumpart of corpora quadrigemina; important for auditory reflexes
tegmentumthe collection of cells and nerve fibers located ventral to the ventricle system in the midbrain, pons and medullagives rise to the middle cerebellar peduncle
cerebral aqueductcanal connecting third and fourth ventricles, passing through midbrainalso known as: aqueduct of Sylvius
pons
ventricle, fourthmidline space between cerebellum posteriorly and pons and upper medulla anteriorlycommunicates anterosuperiorly with third ventricle via cerebral aqueduct; drains CSF via median aperature and lateral aperatures
StructureDescriptionSignificance
medulla oblongata
ventricle, fourthmidline space between cerebellum posteriorly and pons and upper medulla anteriorlycommunicates anterosuperiorly with third ventricle via cerebral aqueduct; drains CSF via median aperature and lateral aperatures
central canal of spinal cordsmall opening in the center of the spinal cordcontinuous with the central canal of the medulla and, through it, with the fourth ventricle of the brain

Ventricular System of the Brain

StructureDescriptionSignificance
ventricle, lateralpaired spaces within cerebral hemispheresthey drain cerebrospinal fluid to the third ventricle via the interventricular foramina (of Monroe)
ventricle, thirdmidline space within the diencephalon between the paired dorsal thalami and the hypothalamuscommunicates rostrolaterally with paired lateral ventricles via interventricular foramina, communicates posteroinferiorly with fourth ventricle via cerebral aqueduct
ventricle, fourthmidline space between cerebellum posteriorly and pons and upper medulla anteriorlycommunicates anterosuperiorly with third ventricle via cerebral aqueduct; drains CSF via median aperature and lateral aperatures
choroid plexusvascular membranes that occur within the ventriclesproduction of cerebrospinal fluid
interventricular foramencommunication between the lateral ventricle and the third ventricle; paired, one on each sidealso known as: foramina of Monro
cerebral aqueductcanal connecting third and fourth ventricles, passing through midbrainalso known as: aqueduct of Sylvius
median aperaturemidline, irregular foramen draining fourth ventricle posteroinferiorly into cerebellomedullary cisternalso known as: foramen of Magendie
lateral aperaturepaired foramina draining fourth ventricle laterally into cerebellomedullary cisternalso known as: foramina of Luschka
central canal of spinal cordsmall opening in the center of the spinal cordcontinuous with the central canal of the medulla and, through it, with the fourth ventricle of the brain

Blood Supply to the Brain

Artery Source Branches Supply to Notes
anterior spinal contributions received from several arteries (vertebral, posterior intercostal, subcostal, lumbar, lateral sacral aa.) pial arterial plexus meninges; spinal cord; medulla (dorsal motor nucleus of cranial nerve X, nucleus ambiguus, spinal accessory nucleus and hypoglossal nucleus) anterior spinal a. anastomoses with the anterior radicular brs. of the spinal rami of the vertebral, posterior intercostal, subcostal, lumbar and lateral sacral aa.
basilar formed by the joining of the two vertebral aa. pontine brs., anterior inferior cerebellar a., superior cerebellar a., two posterior cerebral aa. (terminal brs.) pons (motor nucleus of cranial nerve V, chief sensory nucleus of cranial nerve V, abducens nucleus, facial nucleus, superior salivatory nucleus); oculomotor nucleus; nucleus of Edinger-Westphal; cerebellum; posterior cerebrum basilar a. contributes blood to the cerebral arterial circle
cerebellar, anterior inferior basilar a. labyrinthine a. (usually) pons (motor nucleus of cranial nerve V, chief sensory nucleus of cranial nerve V, abducens nucleus, facial nucleus, superior salivatory nucleus); cerebellum; inner ear anterior inferior cerebella a. shares its region of supply with branches of the basilar a.
cerebellar, posterior inferior vertebral a. posterior spinal a. part of cerebellum; medulla (cochlear nucleus, vestibular nucleus, dorsal motor nucleus of cranial nerve X, nucleus ambiguus) posterior inferior cerebellar a. shares its region of supply with the vertebral a. and anterior spinal a. (watershed region)
cerebellar, superior basilar a. no named branches upper cerebellum; trochlear nucleus there may be more than one superior cerebellar a. arising from the basilar a. on each side
cerebral, anterior internal carotid a. anterior communicating a., medial frontobasal a., polar frontal a., callosomarginal a., precuneal a. medial and inferior portions of the frontal lobe; medial side of the parietal lobe; corpus callosum and part of the limbic lobe; olfactory bulb and tract; optic nerve, optic chiasm and optic tract the anterior communicating a. unites the two anterior cerebral aa. across the midline
cerebral arterial circle an anastomotic circle of blood vessels formed by portions of the following vessels: posterior cerebral aa. (2); posterior communicating aa. (2); internal carotid aa. (2); anterior cerebral aa. (2); anterior communicating a. this is an anastomotic loop; major named vessels connect here, but there are no named branches of the arterial circle brain and midbrain also known as: arterial circle of Willis
cerebral, middle internal carotid a. lateral frontobasal a.; prefrontal sulcal a.; precentral sulcal a.; central sulcal a.; anterior parietal a.; posterior parietal a.; anterior, middle and posterior temporal aa. frontal, parietal and temporal lobes, especially on their lateral surfaces the middle cerebral a. is the direct continuation of the internal carotid a.
cerebral, posterior basilar a. posterior cerebral a.; anterior and posterior temporal brs.; medial occipital a. part of the brainstem (oculomotor nucleus, nucleus of Edinger-Westphal, trochlear nucleus); medial and inferior portions of the temporal lobe; occipital lobe the two posterior cerebral aa. are the terminal brs. of the basilar a.
communicating, anterior anterior cerebral a. perforating aa. an anastomotic connection anterior communicating a. is a short vessel of anastomosis which crosses the midline to join the paired anterior cerebral aa.; it is part of the Circle of Willis
communicating, posterior internal carotid a. perforating aa. an anastomotic connection a vessel of anastomosis which connects the internal carotid a. to the posterior cerebral a.; part of the cerebral arterial circle (of Willis)
ophthalmic internal carotid a. central retinal a., lacrimal a., muscular brs., anterior ethmoidal a., posterior ethmoidal a., medial palpebral a., supraorbital a., supratrochlear a., dorsal nasal a. optic nerve, optic chiasm optic tract, retina, extraocular mm., eyelids, forehead, ethmoidal air cells, lateral nasal wall, dorsum of the nose ophthalmic a. provides the only artery to the retina (central retinal a.)
vertebral subclavian a.(1st part) spinal brs., muscular brs., anterior spinal a., posterior inferior cerebellar a., medullary brs., meningeal brs., basilar a. deep neck, cervical spinal cord, spinal cord; medulla (dorsal motor nucleus of cranial nerve X, nucleus ambiguus, spinal accessory nucleus and hypoglossal nucleus) vertebral a. anastomoses with the internal carotid a. in the cerebral arterial circle (of Willis); it courses through the transverse foramina of vertebrae C1-C6
spinal, anterior contributions received from several arteries (vertebral, posterior intercostal, subcostal, lumbar, lateral sacral aa.) pial arterial plexus meninges; spinal cord; medulla (dorsal motor nucleus of cranial nerve X, nucleus ambiguus, spinal accessory nucleus and hypoglossal nucleus) the anterior spinal a. anastomoses with the anterior radicular brs. of the spinal rami of the vertebral, posterior intercostal, subcostal, lumbar and lateral sacral aa.

Veinous Drainage of the Brain

Vein Tributaries Drains Into Regions Drained Notes
cerebral, great formed by the union of the paired internal cerebral vv. straight sinus deep portions of the cerebrum great cerebral v. is a very short vessel
cerebral, inferior tributaries are unnamed cavernous sinus, transverse sinus, superior petrosal sinus inferior aspect of the cerebral hemispheres inferior cerebral vv. are numerous
cerebral, superior tributaries are unnamed superior sagittal sinus superior aspect of the cerebral hemispheres superior cerebral vv. bleed into the subdural space when injured, resulting in a subdural hematoma; also known as: bridging vv.
inferior sagittal sinus unnamed tributaries from the falx cerebri and cerebral hemispheres unites with the great cerebral v. to form the straight sinus medial surfaces fo the cerebral hemispheres inferior sagittal sinus is directly superior to the corpus callosum in the free margin of falx cerebri
inferior petrosal sinus cavernous sinus sigmoid sinus, at its distal end all regions drained by the cavernous sinus, including the orbit and brain inferior petrosal sinus lies within the dura mater along the inferior portion of the petrous part of the temporal bone
occipital sinus no named tributaries confluens of sinuses cerebellum lies within the dura mater at the base of the falx cerebelli
superior petrosal sinus cavernous sinus sigmoid sinus, at its proximal end all regions drained by the cavernous sinus, including the orbit and brain superior petrosal sinus lies on the petrous ridge within the dura mater at the line of attachment of the tentorium cerebelli
superior sagittal sinus v. of the foramen cecum; superior cerebral vv. confluens of sinuses cerebral hemispheres superior sagittal sinus occupies the superior part of the falx cerebri; lateral lacunae receive grossly visible arachnoid granulations
straight sinus inferior sagittal sinus, great cerebral vein, superior cerebellar vv. confluens of sinuses deep parts of the cerebrum, cerebellum straight sinus lies within the junction of the falx cerebri and tentorium cerebelli; also known as: sinus rectus
transverse sinus confluens of sinuses, inferior cerebral vv. sigmoid sinus brain lies within the line of attachment of the tentorium cerebelli to the inner surface of the calvaria


Some of the material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest and Jaye Schlesinger
Published by ILOC, Inc., New York. Copyright 1995.

Content of tables edited for use in this course by Patrick W. Tank, Ph.D.
Copyright 2001, Department of Anatomy and Neurobiology, University of Arkansas for Medical Sciences.
Unauthorized use is prohibited.



COMPUTER ASSISTED INSTRUCTION

Anatomy Tables
Review Questions for Gross Anatomy: 12. Cranial Cavity, Meninges, Brain
Human Anatomy
Netter Interactive Atlas
A.D.A.M.



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