BRAIN—AN OVERVIEW
Structure | Description | Significance |
---|---|---|
Forebrain | Prosencephalon | Comprised of: telencephalon or cerebral hemispheres and diencephalon; site of termination of cranial nerves I and II; contains lateral and third ventricles |
Midbrain | Mesencephalon | Connects forebrain and hindbrain; site of origin of cranial nerves III and IV; contains cerebral aqueduct |
Hindbrain | Rhombencephalon | Comprised of: metencephalon or pons and cerebellum and myelencephalon or medulla oblongata; site of origin for cranial nerves V-XII (except spinal part of accessory nerve); contains fourth ventricle |
Telencephalon | Rostral part of forebrain | Comprised of: cerebral hemispheres and basal ganglia; contains lateral ventricles |
Diencephalon | Caudal portion of forebrain | Comprised of: thalamus, metathalamus, subthalamus, epithalamus; contains third ventricle |
Mesencephalon | Midbrain | Contains the corpora quadrigemina |
Metencephalon | Rostral part of rhombencephalon | Comprised of: pons and cerebellum |
Myelencephalon | Caudal part of rhombencephalon | Comprised of: medulla oblongata; medulla becomes continuous with the spinal cord at the level of the foramen magnum |
FEATURES OF THE BRAIN—LATERAL VIEW
Structure | Description | Significance |
---|---|---|
Cerebral hemispheres | Telencephalon | Comprised of: cortex featuring gyri, sulci, fissures and lobes; commissures connecting parts; basal ganglia; contains lateral ventricles; termination of the olfactory tract |
Longitudinal fissure | Midline, sagittal cleft separating the paired cerebral hemispheres | Contains the falx cerebri |
Frontal pole | The most anterior part of the cerebral hemisphere | Frontal pole is part of the frontal lobe |
Temporal pole | The most anterior part of the temporal lobe | |
Occipital pole | The most posterior part of the cerebral hemisphere | Occipital pole is part of the occipital lobe; composedof primary visual cortex |
Central sulcus | Separates frontal and parietal lobes | Separates the precentral gyrus (motor) from the postcentral gyrus (sensory) |
Frontal lobe | Rostral to central sulcus | Contains prefrontal (emotions, personality) and precentral (primary and secondary motor) areas |
Parietal lobe | Separated from the frontal lobe by the central sulcus, separated from occipital lobe by line through parieto occipital sulcus | Contains the primary and secondary somatosensory areas |
Temporal lobe | Separated from the frontal lobe by the lateral sulcus | Primarily concerned with hearing and memory/ learning |
Occipital lobe | Posterior to an imaginary line through parieto-occipital sulcus | Contains the primary and secondary visual cortex |
Precentral gyrus | Most caudal gyrus of the frontal lobe; it lies rostral to the central sulcus | Contains the primary motor cortex |
Postcentral gyrus | Most rostral gyrus of the parietal lobe; it lies caudal to the central sulcus | Contains the primary sensory cortex |
Superior temporal gyrus | Gyrus between the lateral sulcus and the superior temporal sulcus | Contains the primary auditory cortex |
Middle temporal gyrus | Gyrus between the superior and inferior temporal sulci | |
Inferior temporal gyrus | Gyrus between the inferior temporal sulcus and the inferior margin of the temporal lobe | |
Insula | Portion of the cerebrum located deeply within the lateral sulcus | Also known as the island of Reil |
Straight gyrus | Gyrus located on the medial side of the olfactory tract | Also known as: gyrus rectus |
Uncus | Portion of the cerebral cortex on the medial side of the parahippocampal gyrus and overlying the amygdala; located near the free edge of the tentorium cerebelli | Contains olfactory cortex |
Longitudinal sulcus | Midline, sagittal cleft separating the paired cerebral hemispheres | Also known as: longitudinal fissure |
Precentral sulcus | The sulcus anterior to the precentral gyrus | In conjunction with the central sulcus, it defines the precentral gyrus (motor) |
Postcentral sulcus | The sulcus posterior to the postcentral gyrus | In conjunction with the central sulcus, it defines the postcentral gyrus (sensory) |
Lateral sulcus | Separates frontal lobe and temporal lobe | The insula lies in the floor of this sulcus |
Superior temporal sulcus | Sulcus between the superior and middle temporal gyri | Used to define the superior and middle temproal gyri |
Inferior temporal sulcus | Sulcus between thIe middle and inferior temporal gyri | Used to define the middle and inferior temporal gyri |
Parieto-occipital sulcus | Sulcus between the parietal and occipital lobes | Landmark used to define the borders of the parietal and occipital lobes when viewing the cerebral hemisphere from a medial perspective |
Preoccipital sulcus | A shallow notch in the inferior surface of the cortex (superior to the cerebellum) as seen in lateral view | A surface landmark for defining the border between the parietal and occipital lobes |
Brainstem | Comprised of: midbrain, pons and medulla oblongata | Origin of most of the cranial nerves |
Midbrain | Mesencephalon | Connects forebrain and hindbrain; the site of origin of cranial nerves III and IV; contains cerebral aqueduct |
Pons | Anterior portion of the metencephalon | The site of origin of cranial nerves V, VI, VII and VIII; forms part of the anterior wall of the fourth ventricle |
Medulla oblongata | Also known as: myelencephalon; most caudal portion of the brainstem | It 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), and XII |
FEATURES OF THE BRAIN—INFERIOR VIEW
Structure | Description | Significance |
---|---|---|
Cerebral hemispheres | Telencephalon | Comprised of: cortex featuring gyri, sulci, fissures and lobes; commissures connecting parts; basal ganglia; contains lateral ventricles; termination of the olfactory tract (cranial nerve I) |
Longitudinal fissure | Midline, sagittal cleft separating the paired cerebral hemispheres | Longitudinal sulcus |
Frontal pole | The most anterior part of the cerebral hemisphere | Frontal pole is part of the frontal lobe |
Temporal pole | The most anterior part of the temporal lobe | |
Occipital pole | The most posterior part of the cerebral hemisphere | Occipital pole is part of the occipital lobe; composed of primary visual cortex |
Frontal pole | Rostral to central sulcus | Contains prefrontal (emotions, personality) and precentral (primary motor) areas |
Temporal lobe | Separated from the frontal lobe by the lateral sulcus | Primarily concerned with hearing and memory/learning |
Occipital lobe | Posterior to an imaginary line through parieto-occipital sulcus | Contains the primarily visual cortex |
Limbic lobe | Structures on the medial surface of the cerebral hemisphere which surround the rostral brainstem; includes the subcallosal gyrus, cingulate gyrus and parahippocampal gyrus | Primarily concerned with emotions and memory |
Parahippocam-pal, gyrus | Gyrus on the inferior surface of the temporal lobe that lies lateral to the midbrain | The uncus is a medial projection of the parahippocampal gyrus |
Straight gyrus | Gyrus located on the medial side of the olfactory tract | Gyrus rectus |
Lingual gyrus | Gyrus lying inferior to the calcarine sulcus | Contains primary visual cortex |
Uncus | Portion of the cerebral cortex on the medial side of the parahippocampal gyrus and overlying the amygdala; located near the free edge of the tentorium cerebelli | Contains olfactory cortex |
Apex of cuneus | Portion of the cuneus seen in an inferior view of the cerebral hemisphere | Contains part of the visual cortex |
Longitudinal sulcus | Midline, sagittal cleft separating the paired cerebral hemispheres | Longitudinal fissure |
Olfactory sulcus | Sulcus that defines the lateral margin of the straight gyrus | Contains the olfactory bulb and tract |
Mamillary body | Part of the hypothalamus; a small spherical projection on the inferior surface of the floor of the third ventricle posterior to the hypophysis | Involved with memory and learning |
Brainstem | Comprised of: midbrain, pons and medulla oblongata | Origin of most of the cranial nerves |
Midbrain | Mesencephalon | Connects forebrain and hindbrain; the site of origin of cranial nerves III and IV; contains cerebral aqueduct |
Pons | Anterior portion of the metencephalon | The site of origin of cranial nerves V VI, VII and VIII; forms part of the anterior wall of the fourth ventricle |
Medulla oblongata | Myelencephalon; most caudal portion of the brainstem | It 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), and XII |
Olfactory bulb | Flattened, oval enlargement at the anterior tip of the olfactory tract | Contains 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 tract | Ribbon-like nerve tract that courses from the olfactory bulb to the cerebral cortex; it courses in the olfactory sulcus | Carries the sense of smell |
Optic chiasm | Crossover point for the nasal fibers of both retinas | Lateral visual fields (medial retinal fibers) project to the contralateral occipital lobe |
Hypophysis | Midline projection of neural and endocrine tissue attached to the floor of the diencephalon | Also known as: pituitary gland |
FEATURES OF THE BRAIN—MID-SAGITTAL VIEW
Structure | Description | Significance |
---|---|---|
Cerebral hemispheres | Telencephalon | Comprised of: cortex featuring gyri, sulci, fissures and lobes; commissures connecting parts; basal ganglia; contains lateral ventricles; termination of the olfactory tract (cranial nerve I) |
Longitudinal fissure | Midline, sagittal cleft separating the paired cerebral hemispheres | Longitudinal sulcus; contains the falx cerebri |
Frontal lobe | Rostral to central sulcus | Contains prefrontal (emotions, personality) and precentral (primary motor) areas |
Parietal lobe | Separated from the frontal lobe by the central sulcus, separated from occipital lobe by line through parieto-occipital sulcus | Contains the primary and secondary somatosensory areas |
Occipital lobe | Posterior to line through parieto-occipital sulcus | Contains the primary and secondary visual cortex |
Limbic lobe | A border (limbus = Latin for border) of cortical tissue surrounding the third ventricle; comprised of: cingulate gyrus, parahippo-campal gyrus, uncus and other small portions of the adjacent cortex | Part of the brain responsible for behavior and emotions |
Cingulate gyrus | The portion of the limbic lobe that lies superior to the corpus callosum | Cingulate gyrusis bounded by the callosal sulcus and the cingulate sulcus |
Straight gyrus | Gyrus located on the medial side of the olfactory tract | Gyrus rectus |
Lingual gyrus | The portion of the occipital lobe that lies inferior to the calcarine sulcus | Cortical projection of the upper half of the contralateral visual field |
Cingulate sulcus | The sulcus that lies superior to the cingulate gyrus | |
Central sulcus | Separates the frontal lobe from the parietal lobe; separates sensory cortex from motor cortex | Fissure of Rolando |
Parieto-occipital sulcus | Sulcus on the medial surface of the cerebral hemisphere that lies between the precuneus and the cuneus | Forms the boundary between the parietal lobe and the occipital lobe |
Calcarine sulcus | Sulcus between the lingual gyrus and the cuneus | Primary visual cortex is both superior and inferior to it |
Cuneus | Part of the cerebral cortex that forms the upper wall of the calcarine fissure | Cortical projection of the lower half of the contralateral visual field |
Pineal gland | Pineal body | Represents an endocrine gland attached to diencephalon |
Corpus callosum | Midline part of great cerebral commissure | Connects paired cerebral hemispheres |
Anterior commissure | A bundle of association fibers located anterior to the third ventricle | Connections between the left and right temporal lobes |
Posterior commissure | A bundle of association fibers located posterior to the third ventricle, just inferior to the pineal gland | Connections between various areas of the right and left sides of the midbrain |
Optic chiasm | Crossover point for the nasal fibers of both retinas | Lateral visual fields (medial retinal fibers) project to the contralateral occipital lobe |
Thalamus | An egg-shaped collection of nuclei forming part of the lateral wall of the third ventricle | Distributes information to appropriate areas of the cerebral cortex |
Hypothalamus | A collection on nuclei forming the anterior portion of the lateral wall of the third ventricle | Controls visceral activity and elicits phenomena associated with the emotions |
Body of fornix | A group of nerve cell fibers arching beneath the corpus callosum | Main efferent fiber system of the hippocampal formation |
Hypophysis | Midline projection of neural and endocrine tissue attached to the floor of the diencephalon | Pituitary gland |
Brainstem | Comprised of: midbrain, pons and medulla oblongata | Origin of most of the cranial nerves |
Midbrain | Mesencephalon | Connects forebrain and hindbrain; the site of origin of cranial nerves III and IV; contains cerebral aqueduct |
Pons | Anterior portion of the metencephalon | The site of origin of cranial nerves V, VI, VII and VIII; forms part of the anterior wall of the fourth ventricle |
Medulla oblongata | Myelencephalon; most caudal portion of the brainstem | It 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), and XII |
Cerebellum | Posterior part of metencephalon | Largest part of hindbrain; important for coordination of movement |
FEATURES OF THE BRAINSTEM
Structure | Description | Significance |
---|---|---|
Midbrain | Mesencephalon | Connects forebrain and hindbrain; site of origin of cranial nerves III and IV; contains cerebral aqueduct |
Pons | Anterior portion of metencephalon | Site of origin of cranial nerves V, VI, VII and VIII; forms part of the anterior wall of the fourth ventricle |
Medulla oblongata | Myelencephalon; most caudal portion of brainstem | Continuous 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), and XII |
SURFACE FEATURES OF THE BRAINSTEM AS SEEN ON MID-SAGITTAL VIEW
Structure | Description | Significance |
---|---|---|
Midbrain | ||
Tectum | The roof of the midbrain, formed by the superior and inferior colliculi; located dorsal to the cerebral aqueduct | Also known as: quadrigeminal plate |
Superior colliculus | Paired elevations of midbrain tectum | Part of corpora quadrigemina; important for reflex movements of eye, head and neck |
Inferior colliculus | Paired elevations of midbrain tectum | Part of corpora quadrigemina; important for auditory reflexes |
Tegmentum | The collection of cells and nerve fibers located ventral to the ventricle system in the midbrain, pons and medulla | Gives rise to the middle cerebellar peduncle |
Cerebral aqueduct | Canal connecting third and fourth ventricles, passing through midbrain | Also known as: aqueduct of Sylvius |
Pons | ||
Fourth ventricle | Midline space between cerebellum posteriorly and pons and upper medulla anteriorly | Communicates anterosuperiorly with third ventricle via cerebral aqueduct; drains CSF via median aperature and lateral aperatures |
Central canal of spinal cord | Small opening in the center of the spinal cord | Continuous with the central canal of the medulla and, through it, with the fourth ventricle of the brain |
VENTRICULAR SYSTEM OF THE BRAIN
Structure | Description | Significance |
---|---|---|
Lateral ventricle | Paired spaces within cerebral hemispheres | They drain cerebrospinal fluid to the third ventricle via the interventricular foramina (of Monro) |
Third ventricle | Midline space within the diencephalon between the paired dorsal thalami and the hypothalamus | Communicates rostrolaterally with paired lateral ventricles via interventricular foramina, communicates posteroinferiorly with fourth ventricle via cerebral aqueduct |
Fourth ventricle | Midline space between cerebellum posteriorly and pons and upper medulla anteriorly | Communicates anterosuperiorly with third ventricle via cerebral aqueduct; drains CSF via median aperature and lateral aperatures |
Choroid plexus | Vascular membranes that occur within the ventricles | Production of cerebrospinal fluid |
Interventricular foramen | Communication between the lateral ventricle and the third ventricle; paired, one on each side | Also known as: foramina of Monro |
Cerebral aqueduct | Canal connecting third and fourth ventricles, passing through midbrain | Also known as: aqueduct of Sylvius |
Median aperature | Midline, irregular foramen draining fourth ventricle posteroinferiorly into cerebellomedullary cistern | Also known as: foramen of Magendie |
Lateral aperature | Paired foramina draining fourth ventricle laterally into cerebellomedullary cistern | Also known as: foramina of Luschka |
Central canal of spinal cord | Small opening in the center of the spinal cord | Continuous 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 ambiguous, spinal accessory nucleus and hypoglossal nucleus) | Anterior spinal artery anastomoses with the nterior radicular brs. of the spinal rami of the vertebral, posterior intercostal, subcostal, lumbar and lateral sacral artery |
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 ambiguous) | 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 |
Middle cerebral | 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. |
Posterior cerebral | 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. |
Anterior communicating | 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 |
Posterior communicating | 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 |
Anterior spin | 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 ambiguous, 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. |
VENOUS DRAINAGE OF THE BRAIN
Vein | Tributaries | Drains into | Regions Drained | Notes |
---|---|---|---|---|
Great cerebral | 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 |
Inferior cerebral | Tributaries are unnamed | Cavernous sinus, transverse sinus, superior petrosal sinus | Inferior aspect of the cerebral hemispheres | Inferior cerebral vv. are numerous |
Superiorc cerebral | 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 | Confluence 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 |
- Frontal sinus
- Crista galli
- Cribriform plate
- Lesser wing of sphenoid
- Superior orbital fissure
- Superior border of petrous part of temporal bone
- Dense shadow of petrous part of temporal bone
- Perpendicular plate of the ethmoid
- Vomer
- Maxillary sinus
- Inferior concha
- Ramus of mandible
- Frontal sinus
- Ethmoidal sinus
- Sphenoidal sinus
- Maxillary sinus
- Anterior clinoid processes
- Hypophyseal fossa
- Posterior clinoid processes
- Clivus
- Great density of the petrous part of the temporal bone
- External acoustic meatus
- Mastoid cells
- Nasopharynx
- Angle of mandible
- Anterior arch of the atlas
- Dens of axis
- Posterior arch of the atlas
- Internal occipital protuberance
- Coronal suture
- Lambdoid suture
AXIAL ANATOMY—BRAIN
NAMED GYRI AND SULCI
AnG | angular gyrus cerebellum |
FP | frontal pole |
IFG | inferior frontal gyrus |
IOG | inferior occipital gyrus |
ITG | inferior temporal gyrus |
LOG | lateral occipital gyrus |
MFG | middle frontal gyrus |
MTG | middle temporal gyrus |
OG | orbital gyrus pons |
oper | pars opercularis (IFG) |
orb | pars orbitalis (IFG) |
tri | pars triangularis (IFG) |
poCG | postcentral gyrus |
preCG | precentral gyrus |
SFG | superior frontal gyrus |
SOG | superior occipital gyrus |
SPL | superior parietal lobe |
STG | superior temporal gyrus |
SmG | supramarginal gyrus |
TP | temporal pole |
cs | central sulcus (Rolandic) |
hr | horizontal ramus |
ifs | inferior frontal sulcus |
ios | inferior occipital sulcus |
ips | intraparietal sulcus |
syl | lateral fissure (Sylvian) |
los | lateral occipital sulcus |
ls | lunate sulcus |
pof | parieto-occipital fissure |
pocs | postcentral sulcus |
precs | precentral sulcus |
sfs | superior frontal sulcus |
tos | transoccipital sulcus |
vr | vertical ramus |
ac | anterior commissure |
cals | calcarine sulcus |
cings | cingulate sulcus |
CingG | cingulate gyrus |
ccb | corpus callosum (body) |
ccg | corpus callosum (genu) |
ccs | corpus callosum (splenium) |
cuneus | |
fornix | |
lingual | lingual gyrus |
mb | mamillary bodies |
PL | paracentral lobule precuneus |
q | quadrigeminal plate |