Neuro Flashcards

Question

Temporal Lobe: Vasculature

Answer 1

* Arterial supply: * Anterior choroidal * Middle cerebral * Basilar * Venous drainage: * Superficial middle cerebral vein * Inferior anastomotic vein of Labbe * Posterior choroidal vein

Answer 2

Wernicke’s area can be on either side, most commonly the left

Answer 3

The frontal lobe is by far the largest of the four lobes of the cerebrum (along with the parietal lobe, temporal lobe, and occipital lobe), and is responsible for many of the functions which produce voluntary and purposeful action.

Answer 4

The frontal lobe is the largest lobe accounting for 41% of the total neocortical volume. The frontal lobe resides largely in the anterior cranial fossa. Its most anterior part is known as the frontal pole, and extends posteriorly to the central (Rolandic) sulcus which separates it from the parietal lobe. Posteroinferiorly it is separated from the temporal lobe by the lateral sulcus (sylvian fissure), although not seen from the surface is the insular cortex which is hidden deep to the lateral sulcus The interhemispheric fissure separates its medial surface from the contralateral frontal lobe. The frontal lobe is roughly pyramidal in shape, with three cortical surfaces: * Lateral surface (largest) * Medial (inter-hemispheric) surface * Inferior surface

Answer 5

* Gyri: * superior frontal gyrus * middle frontal gyrus * inferior frontal gyrus * precentral gyrus (primary motor area) * Sulci: * superior frontal sulcus * inferior frontal sulcus * precentral sulcus

Answer 6

The medial surface of the frontal lobe, abutting the falx in the midline, is primarily divided by the curving cingulate sulcus, which parallels the outer outline of the corpus callosum. Above the cingulate sulcus is the medial continuation of the superior frontal gyrus which is usually divided into two parts by a short ascending branch from the cingulate sulcus. * medial frontal gyrus * paracentral lobule

Answer 7

Gyrus recti medially Orbital gyri arranged in a H configuration (Medial, lateral, anterior and posterior orbital gyri)

Answer 8

* anterior: frontal bone * superiorly: frontal bone (anteriorly), coronal suture, and parietal bone (posteriorly) * posterior: central sulcus and parietal lobe * inferolaterally: lateral sulcus and temporal lobes * inferior: floor of anterior cranial fossa

Answer 9

* middle cerebral artery (MCA): lateral frontal lobe * anterior cerebral artery (ACA): medial frontal lobe

Answer 10

The occipital lobe is the smallest of the four lobes of the brain. Location: Posterior to the temporal and parietal lobes, sitting on top of the tentorium Function: Primary and secondary visual cortex

Answer 11

* Triangular in shape * Separated from the parietal and temporal lobes by the parieto-occipital sulcus and the parietotemporal line * Medially it is devided into hemisphere by the longitudinal fissure * The calcarine sulcus runs horizontally across with the cuneus above and the lingual gyrus below

Answer 12

* Primary visual cortex – primary visual processing * Secondary visual cortex – visual association

Answer 13

* Anterior: parietal and temporal lobes * Posterior: occipital bone * Superior: Parietal lobe and parietal bone * Inferior: tentorium cerebelli * Medial: transverse sinuses, confluence of sinuses, straight sinus

Answer 14

* Arterial supply: * Branches of the posterior cerebral artery * Venous: * Straight sinus * Superior sagittal sinus * Transverse sinuses

Answer 15

The parietal lobe is one of the four lobes of the brain located between the frontal and occipital lobes. Function: Sensory processing, communication, proprioception

Answer 16

* Lobe extends from the central sulcus anteriorly to the parieto-occipital fissure posteriorly. * The lateral sulcus corresponds to its inferolateral boundary, separating it from the temporal lobe. Divided by the medial longitudinal fissure Gyri: * postcentral gyrus (primary sensory area) * superior parietal lobule * inferior parietal lobule (Wernicke's area)

Answer 17

* Anterior: frontal lobe * Posterior: occipital lobe * Superior: parietal bone * Inferior: temporal lobe

Answer 18

* Blood supply: * middle cerebral artery (MCA) * anterior cerebral artery (ACA): medial parietal lobe * posterior cerebral artery (PCA): posterior medial parietal lobe * Venous: * Superior sagittal sinus * Straight sinus * Inferior superficial cerebral vein (Labbe)

Answer 19

Small deep paired lobe of the brain, covered by the frontal, parietal and temporal opercula (lids). Function: * The insula has a number of disparate functions, serving as the primary gustatory cortex, as well as having important connections to language and visual-vestibular integration. Additionally, it also has important autonomic function, particularly sympathetic tone from the right insula; damage to this area has been associated with cardiac arrhythmias.

Answer 20

* Deep to the lateral sulcus (Sylvain fissure) * The insula is shaped like a irregular pyramid, with its trapezoid base facing medially. * The base is circumscribed by the circular sulcus, although, more precisely, it is bounded by four peri-insular sulci: anterior, inferior, superior, and posterior 3-4. * The apex points laterally into the Sylvian fissure. * The insular cortex is divided into two lobules, anterior and posterior, by the central sulcus of the insula, which passes obliquely from posterosuperior to anteroinferior.

Answer 21

The insula is supplied by perforating branches from the middle cerebral artery (MCA), usually from the M2 segment.

Answer 22

The circle of Willis is an arterial polygon that supplies the brain Location: Suprasellar cistern around the pituitary infundibulum Function: Anastomotic supply of oxygenated blood to the brain

Answer 23

Dividable into anterior and posterior circulations

Answer 24

Supplied by the internal carotid arteries Branches: * Middle cerebral arteries * Anterior cerebral arteries * Anterior communicating artery

Answer 25

There cerebral meninges are the coverings of the brain **Function:** Protect the brain, circulation of CSF, venous return

Answer 26

3 layers in total: * Dura mater – outer most, has outer endosteal layers and inner meningeal layers, folds of the dura mater make the dural venous sinuses, also known as the pachymeninges * Arachnoid mater – diffuse fibrous middle layer, CSF space is deep to the arachnoid mater, does not extend in the sulci * Pie mater – closely adhered to the brain very thin, extends into the sulci

Answer 27

**Arterial supply:** * Anterior meningeal arteries * Middle meningeal arteries * Posterior meningeal arteries **Venous drainage:** * Multiple unnamed veins into the dural venous sinuses **Dural venous sinuses:** * Superior and inferior sagittal sinuses * Straight sinus * Transverse sinuses * Sigmoid sinuses * Sphenoparietal sinus * Superior and inferior petrosal sinuses * Cavernous and anterior and posterior intercavernous sinues **Innervation:** Meningeal nerves branches of the: * Trigeminal nerves * Glossopharyngeal nerves * Vagus nerves **Lymphatics:** Deep cervical

Answer 28

* Mega cisterna magna * Absence of the confluence of sinuses * Arachnoid cysts * Dural calcifications

Answer 29

The cerebral ventricular system is a system of cerebraospinal fluid spaces connected by formaminae. **Function:** Circulation of cerebrospinal fluid

Answer 30

Contains 20-25ml of CSF in normal adult 2 lateral ventricles, 3^rd ventricle and a forth ventricle

Answer 31

* One in each cerebral hemisphere * Each has a frontal horn, body, temporal horn and an occipital horn * Each communicates with the third ventricle by means of an interventricular foramen (of Munro) at the junction of the anterior horn and body * Contains the choroid plexus which produces CSF * Frontal horn relations * roof: corpus callosum (rostrum / genu) * lateral: caudate nucleus * medial: septum pellucidum * Body relations * roof: corpus callosum body * medial: septum pellucidum * floor: thalamus * Temporal horn relations * lateral: tapetum of the corpus callosum * roof: tail of caudate nucleus, amygdaloid nucleus * floor: hippocampus * Occipital horn relations * lateral: tapetum of corpus callosum * floor: collateral sulcus

Answer 32

* The third ventricle is a slit-like cavity between the thalami * Sometimes the thalami are connected to each other, forming the interthalamic adhesion * Relations * lateral: thalamus * floor: hypothalamus * roof: anterior commissure, body of fornix * anterior: lamina terminalis * Has several recesses: * supra-optic recess (above the optic chiasm) * infundibular recess (above the pituitary stalk) * posteriorly there is a pineal and suprapineal recesses * Choroid plexuses of the third ventricle invaginates the roof of the ventricle * Cerebral aqueduct is the narrow channel in the midbrain that connects the third and fourth ventricles

Answer 33

* Extends from the cerebral aqueduct (of Sylvius) to the obex and is filled with CSF * Relations: * roof: cerebellum * floor (ventrally): rhomboid fossa (formed by the back of the pons and medulla oblongata) * lateral walls: cerebellar peduncles * CSF enters the ventricle via the cerebral aqueduct and leaves via one of four routes: * via the obex and into the central spinal canal * via the median aperture (of Magendie) into the cisterna magna * via ones of the two lateral apertures (of Luschka) into the cerebellopontine cistern

Answer 34

Small vascular organs located in all ventricles except the anterior and occipital horns of the lateral ventricles, produce CSF, arterial supply anterior and posterior coroidal arteries

Answer 35

* Cavum septum pellicidum * Cavum vergae * Cavum veli interpositi * Interthalamic adhesion may not be present

Answer 36

The pituitary gland is the main exocrine interface between the central nervous system and the rest of the body

Answer 37

Location: with the sella turcica Dividable into anterior and poster components:

Answer 38

The anterior pituitary is surrounded by a thin fibrous capsule with thin septa extending into the gland Parts: * Pars distalis – arises from the anterior wall of the Rathke’s pouch * Pars tuberalis – surrounds the anterior aspect of the infundibular stalk * Pars intermedia – thin epithelial layer between the pars distalis and the neurohypophysis **Hormones produced** – GH, FSH, TSH, ACTH, LH, FSH, Prolactin **Blood supply:** Portal system supplied by the superior hypophyseal artery (ophthalmic portion of the internal carotid artery)

Answer 39

Direct extension from the hypothalamus Does not synthesise but releases ADH and oxytocin which has travelled down the stalk via herring bodies from the supraoptic and paraventricular nucleus of the hypothalamus The infundibular stalk is considered part of the posterior pituitary Blood supply: Inferior hypophyseal network primary supplied by the inferior hypophyseal artery (from the meningohypophyseal trunk)

Answer 40

* Inferior – sphenoid sinus * Anterior – clinoid process and anterior intercavenous sinus * Laterally – the cavernous sinuses * Superior – the diaphragma sellae and the suprasellar cistern * Posterior – posterior intercavernous sinus and dorsum sellae

Answer 41

* Hypoplasia * Empty sella * Duplication

Answer 42

The pons is the middle of the three parts of the brainstem, sitting above the medulla and below the midbrain. It acts as a relay between the cerebellum and cerebral hemispheres.

Answer 43

The pons has a bulbous shape and has two main components - the ventral pons and the dorsal tegmentum.

Answer 44

The ventral pons consists of white matter tracts (corticospinal, corticobulbar and corticopontine tracts) with transverse fibres contributing to the bulk of the pons.

Answer 45

The dorsal tegmentum is continuous with the tegmentum of the medulla and the midbrain. It contains multiple white matter tracts (medial longitudinal fasciculus, medial lemniscus, lateral lemniscus) and grey matter nuclei (cranial nerves). Within the dorsal tegmentum lie four cranial nerve nuclei: * trigeminal nerve (CN V): many motor, sensory and mesencephalic nuclei extending from the pons to the upper cervical cord * abducens nerve (CN VI): motor nucleus * facial nerve (CN VII): including superior salivary, motor and solitary tract nuclei * vestibulocochlear nerve (CN VIII): including vestibular and cochlear nuclei Posteriorly, the pons is connected to the cerebellum by the middle cerebellar peduncle.

Answer 46

* Anteriorly: prepontine cistern (contains CN V & VI) * Laterally: cerebellopontine angle cistern (contains CN VII & VIII) * Posteriorly: fourth ventricle (the pons makes up the anterior wall) * Superiorly: continuous with the midbrain * Inferiorly: continuous with the medulla

Answer 47

**Arterial:** * medial branches of the superior cerebellar artery * pontine branches of basilar artery **Venous:** * Lateral and transverse pontine veins

Answer 48

* Basilar artery fenestration * Pontine artery branches from the superior cerebellar artery or anterior inferior cerebellar artery

Answer 49

The thalamus is the largest structure of the diencephalon **Function:** Relay centre, consciousness, sleep and memory

Answer 50

* Composed of 2 symetrical egg shaped masses which are typically connected midline by the interthalamic adhesion. * The grey matter of the thalamus is divided by a y shaped layer of white matter called the internal medullary lamina. This divides the thalamus into anterior, medial and lateral parts. * The thalamus contains over 50 distinct nuclei.

Answer 51

* Superior: Body of the fornix and the head of the caudate * Lateral: posterior limb of the internal capsule * Medial: 3^rd ventricle and interthalmic adhesion * Inferior: Hypothalamus * Anterior: Interventricular foramen of Monroe * Posterior: Occipital horns of the lateral ventricle

Answer 52

**Arterial supply:** * Perforating vessels from the posterior cerebral, posterior communicating and basilar arteries **Venous drainage:** * Internal cerebral vein **Lymphatics:** * Via CSF

Answer 53

* Absence of the interthalmic adhesion * Artery of Percheron (single vessel from the PCA supplying the medial thalamus)

Answer 54

The visual pathways transmit visual information from the retina within the eyes to the primary visual cortex of the occipital lobe as well as the pre tectal nuclei and superior colliculi

Answer 55

* Bipolar neurons (first order) on the retina receive light signals and synapse with ganglion cells (second order) locally. * Axons from the ganglia exit via the optic disc to form the optic nerves * Each optic nerve carries the information from one eye, they are covered in meninges * They pass through the optic canals, with the ophthalmic arteries.

Answer 56

* The optic nerves continue posteriorly in the suprasella cistern * They converge at the optic chiasm anterior to the pituitary stalk * Fibres from the nasal side of the retina decussate at the optic chiasm, fibres from the temporal side do not * The optic tracts continue posteriorly from the optic chiasm terminating in the lateral geniculate nuclei of the thalamus (small fibres also enter the midbrain) * From the lateral geniculate nuclei third order neurons form the optic radiations * The optic radiation continues posteriorly to the primary visual cortex * The upper division contains information from the superior rentinal quadrants, it terminates in the upper bank of the calcraine fissure * The lower division contains information from the inferior rentinal quadrants, it terminates in the lower bank of the calcarine fissure

Answer 57

* Retina and distal 1/3 of optic nerve in orbit: central retinal artery * Proximal 2/3 of optic nerve in orbit: ophthalmic artery * Intracranial optic nerve and optic chiasma: anterior cerebral artery small branches and superior hypophyseal artery * Optic tract: small branches of the anterior choroidal artery and posterior communicating artery

Answer 58

The cerebellum is a specialised part of the brain located in the posterior cranial fossa **Function:** Computation of movement and proprioceptive data

Answer 59

* Superior cerebellar from the basilar –supplies the superior surface * Anterior inferior cerebellar from the basilar – anterior inferior * Posterior inferior cerebellar from the vertebral – posterior inferior

Answer 60

The basilar artery is a large artery of the posterior circulation of the brain.

Answer 61

**Origin:** Formed from the confluence of the vertebral arteries at the base of the pons. **Course:** Ascends parallel to the ventral pons in the central groove of the pons in the pre-pontine cistern **Branches:** Numerus small braches to the pons and cerebellum including the: * The anterior inferior cerebellar artery (AICA) * Labyrinthine arteries (normally from AICA) * Superior cerebellar arteries **Termination:** bifurcates to form the two posterior cerebral arteries at the upper pontine boarder

Answer 62

* Anterior: clivus * Posterior: Basilar pons * Superior: Posterior cerebral arteries * Inferior: vertebral arteries * Lateral: Origin; origin of the abducens nerve, termination: origin of the oculomotor nerve

Answer 63

* Persistent carotid-vertebrobasilar anastomoses (mnemonic: TOHP) * Basilar artery fenestration / Island formation * Basilar artery forms in caudal position * Basilar artery is continuation of only one vertebral artery * Two basilar arteries with otherwise normal branches * Anastomosing network instead of a basilar artery

Answer 64

Internal carotid arteries are the primary supply to the anterior circulation of the brain **Function:** supply oxygenated blood to the brain and meninges

Answer 65

Divides into the following segments (Bouthillier classification): * Cervical * Petrosal * Lacerum * Clinoid * Caverous * Ophthalmic * Communicating **Origin:** Bifurcation of the common carotid at the level ~C4 **Course:** ascending through the carotid space, enters the cranial cavity via the carotid canal **Termination:** Branches to for the anterior and middle cerebral arteries

Answer 66

2^nd segment: * Caroticotympanic * Vidian 4^th segment: * Meningohypophyseal * Inferolateral trunk 6^th segment * Ophthalmic artery * Superior hypophyseal 7^th segment: * Posterior communicating artery * Anterior choroidal artery * Anterior communicating artery * Middle cerebral artery

Answer 67

* Anterior: External carotid artery * Lateral: internal jugular vein * Medial: larynx, oropharynx, nasopharynx * Superior: suprasellar cistern * Inferior: Carotid bulb

Answer 68

* Aberrant ICA course * Kissing carotids * Persistent carotid-vertebrobasilar anastomoses * Retropharyngeal ICA

Answer 69

**Origin:** Terminal bifurcation of the Internal carotid artery (the other branch is the anterior cerebral artery **Course:** **Divided into segments: (HIOC)** * M1 – the horizontal segment – from origin to bi/trifurcation * M2 – insular segment from bi/trifurcation to the circular sulcus of the insular lobe * M3 – Opercular branches – within the sylvian fissure * M4 – Cortical segment – branches emerging from the sylvian fissure

Answer 70

**Branches:** **M1: (PAUL)** * Medial and lateral lenticulostriate * Anterior temporal * Polar temporal * Uncal artery **M2:** * Superior and inferior trunks

Answer 71

**M1:** * Basal ganglia * External and internal capsule * Anterior third of the superior, middle and inferior temporal gyri * Polar Regions of the temporal lobe

Answer 72

* MCA duplication * Accessory MCA * MCA fenestration * Early branching of the MCA

Answer 73

The cavernous sinuses are paired dural venous sinuses lateral to the pituitary fossa and body of the sphenoid bone. **Function:** Return of deoxygenated blood from the basicerebrum to the systemic circulation

Answer 74

Formed from reflection of the dura mater Spans from the apex of the orbit to the apex of the petrous temporal bone Diaphragma sella, dural reflection slung between the clinoid processes

Answer 75

* Sphenoparietal sinuses * Intercavenous sinuses anterior and posterior * Superior and inferior ophthalmic veins (inferior ophthalmic vein may drain to the pterygoid plexus) * Superfical middle cerebral vein (of Sylvius) (however this may drain into the sphenoparietal sinus)

Answer 76

* Clival plexus * Paired superior petrosal sinus (to the transverse sinus) * Paired inferior petrosal sinus (to the jugular bulb) * Venous plexus of the internal carotid

Answer 77

Many important structures pass through the cavernous sinuses and there walls OTOM CAT Wall superior to inferior: * Oculomotor nerve * Trochlear nerve * Ophthalmic division of the trigeminal nerve * Maxillary division of the trigeminal nerve Within the sinus: * Abduces nerve laterally * Internal carotid medially

Answer 78

Anterior: apex of the orbit Posterior: cerebral peduncle Medial: pituitary fossa, pituitary gland, sella turcica, hypophseal arteries and veins Superior: suprasella cistern, optic chiasm Inferior: Sphenoid sinus Lateral: temporal lobes

Answer 79

* Inferior ophthalmic vein may not drain here * Septation * Absence * Empty sella

Answer 80

The cerebral venous sinus are venous system formed from folds of the meninges **Function:** return of deoxygentated blood from the brain to the system circulation

Answer 81

Folded dura form sinus which drain from veins to other sinuses or veins Valveless There are paired and unpaired cerebral venous sinuses

Answer 82

Transverse sinuses – from the confluence of sinuses to the sagittal sinuses, receives the superficial cerebral vein of labbe Sigmoid sinuses – from the transverse sinus s-shaped course draining into the jugular bulbs , also receives the sphenoparietal sinus and the superior petrosal sinus Superior and inferior petrosal sinuses – From the right and left cavernous sinuses to the sagittal and jugular bulb respectively Sphenoperietal sinus courses along the ridge of the greater wing of the sphenoid to the cavernous sinsus, also receives the middle superficial cerebral vein Caverous sinuses located either side of the sella, receives the ophthalmic veins (superior and inferior) connected by the anterior and posterior intercavernous sinsus, drains into the superior and inferior petrosal sinuses and basiclival plexus

Answer 83

Internal cavernous sinuses as noted earlier Superior sagittal sinus midline between the falx drains into the confluence of sinuses Inferior sagittal sinus runs in the over the corpus callosum drains into the straight sinus Straight sinus – from the vein of Galen to the confluence of sinuses Occipital sinus – from the occipital bone midline between the cerebellar hemispheres drains into the confluence of sinuses

Answer 84

No confluence – straight and superior sagittal sinuses drain into the right and left transverse sinuses separately No confluence – straight and superior sagittal sinuses fork prior to drain into the straight sinuses

Answer 85

The cerebral veins drain the brain parenchyma and are located in the subarachnoid space. They pierce the meninges and drain further into the cranial venous sinuses.

Answer 86

The cerebral veins lack muscular tissue and valves. The cerebral venous system can be divided into: * superficial (cortical) cerebral veins * deep (subependymal) cerebral veins

Answer 87

There are numerous unnamed superficial veins Large named veins include: * Superficial middle cerebral vein – Begins on the lateral surface, runs in the lateral sulcus, drains into the cavernous or sphenoparietal sinus * Superior anastomotic vein of Trolard – Runs over the lateral aspect of the brain, connects the superior sagittal sinus to the superficial middle cerebral vein * Inferior anastomotic vein of Labbe – Runs between the sylvian fissure and the transverse sinuses The unnamed veins are typically called cortical veins. They run in the sulci and drain the adjacent gyri.

Answer 88

* Medullary veins: * Numerous * Originate 1-2 cm below cortical gray matter * Pass through deep medullary white matter and drain into subependymal veins. * Arranged in a wedge-shaped manner and distributed at a right angle to subependymal veins. Subependymal veins: receive medullary veins and aggregate into greater tributaries, mainly into: Great vein of Galen: * Quadrigeminal cistern * Drains into the straight sinus * Connects to the internal cerebral veins and the basal veins of Rosenthal Internal cerebral veins: * Runs beneath the corpus callosum in the roof of the thord ventricle * Drains: Great vein of Galen Basal veins of Rosenthal * Runs: Medial temporal lobe surface lateral to midbrain through the ambient cistern * Drains: Great vein of Galen

Answer 89

The venous drainage of the orbit is the venous system to drain deoxygenated blood from the orbit to the systemic circulation.

Answer 90

**Origin:** confluence of multiple veins in the superior orbit **Course:** * Medially toward the trochlea between the optic nerve and the rectus muscle * Curves laterally in the posterior orbit * Exits through the fibromuscular cone to leave the orbit via the superior **Termination:** Drains directly into the cavernous sinus **Drains:** * Upper Globe * Upper extraoccular muscles * Lacrimal gland

Answer 91

**Origin:** Confluence of multiple small vessels in the anterior inferior orbit (including some small facial veins which means infection can be transmitted intracranially). **Course:** * Posteriorly within the intraconal space **Termination:** * Then exits the cone and forms 2 tributaries: * Branch through the superior orbital fissure to drain directly into the cavernous sinus * Branch drains through the inferior orbital fissure to drain into the pterygoid plexus **Drains:** * Lower globe * Lower extraocular muscle * Lower eyelid

Answer 92

The phrenic nerves are mixed sensory/motor nerves that course through the neck and thorax to innervate the diaphragm

Answer 93

**Origin:** ventral rami of C3, C4 and C5 **Course:** Passes of the anterior surface of scalenus anterior, over the dome of the apical pleura, entering the superior thoracic aperture posterior to the subclavian veins **Left:** Descends lateral to the left subclavian artery, passes anterior to the hilum, pierces the diaphragm directly to enter the abdominal cavity. **Right:** Descends with the superior and inferior vena cava. Enters the abdomen with the inferior vena cava through the caval hiatus at level T8 Within the abdomen the both divide in the anterior, lateral and posterior branches. Coursing out in a radial pattern. **Supply:** Sole motor supply to each hemidiaphragm, sensation to the central tendon * Diaphragm * Mediastinal pleura * Pericardium * Central diaphragmatic pleura

Answer 94

* Course anterior to subclavian vein * May pierce the anterior scalene muscle * Accessory phrenic nerve * Contribution form C2 or C6 * May supply branch to subclavius

Answer 95

The sympathetic chain is a component of the autonomic nervous system and is composed of general visceral afferent and efferent axons. ## Footnote **Function:** **'fight, fright or flight' (sympathoadrenal) response**

Answer 96

**Location** * The sympathetic chain is external to the spinal column, adjacent to the vertebral bodies and within the perivertebral space. It is comprised of paired, longitudinally arranged, sympathetic ganglia linked together by myelinated axons forming the sympathetic trunk. * It extends from the upper neck to the coccyx. 23 paired sympathetic ganglia and 1 unpaired coccygeal sympathetic ganglion **Origin** The sympathetic chain and ganglia are comprised of discrete sympathetic ganglia (containing neuronal cell bodies) which communicate with each ganglion via the sympathetic trunk (containing myelinated axons).

Answer 97

* Carotid plexus * superior, middle and inferior cardiac nerves form the superficial/deep cardiac plexus and pulmonary plexus - supplies the heart and bronchi * cardiac plexus * oesophageal plexus * thoracic aortic plexus * greater (T5-10) and lesser (T10-11) and least splanchnic (T12) nerves * Superior hypogastric plexus * Inferior hypogastric plexus * Sacral splanchinic nerves

Answer 98

* neck: ascending cervical artery and inferior thyroid artery * thorax: posterior intercostal arteries * abdomen: lumbar arteries * pelvis: lateral and median sacral arteries

Answer 99

* neck: deep cervical chain lymph nodes * thorax: posterior mediastinal lymph nodes * abdomen: para-aortic lymph nodes, cisterna chyli * pelvis: internal iliac lymph nodes

Answer 100

* absent stellate ganglion * doubled superior cervical ganglion * absent superior cardiac branch (usually on the right)

Answer 101

The pituitary fossa is a midline, dural lined structure in the sphenoid bone that houses the pituitary gland.

Answer 102

The anterior, posterior and inferior walls are bony, the lateral walls and roof are formed by dural slings between the anterior and posterior clinoid processes. There is a fenestration in the roof for the infundibulum. **There are four parts to the sellae:** * Anterior: tuberculum sellae * Posterior: dorsum sellae * Inferior: sella turcica * Superior: Diaphragma sellae

Answer 103

* Pituatary gland * Pituatary vessels * Anterior and posterior intercavernous sinuses * CSF * Hypophyseal cistern

Answer 104

* Ant/inf. – sphenoid sinus * Post – clivus, basilar artery, brainstem * Sup – suprasellar cistern, optic chiasm, infundibulum, hypothalamus * Lateral – cavernous sinus

Answer 105

* Empty sella * Pneumatisation of the dorsum sellae

Answer 106

The subarachnoid cisterns are discrete named spaces within the subarachnoid space where the pia mater and arachnoid membrane are not in close approximation. The subarachnoid tissue is not as abundant here as in the normal subarachnoid space and cerebrospinal fluid (CSF) gathers to form pools or cisterns (Latin: "box"). As they are interconnected, the patency is essential for CSF circulation. Being within the subarachnoid space, the cisterns may have vessels and/or cranial nerves passing through them.

Answer 107

* cisterna magna: the largest of the subarachnoid cisterns * prepontine cistern: anterior to the pons * suprasellar cistern: surrounding the infundibulum * interpeduncular cistern: between the cerebral crura * quadrigeminal cistern: superior cistern or cistern of the great cerebral vein * ambient cistern: surrounds the back of the midbrain * cerebellopontine cistern: at the cerebellopontine angle * premedullary cistern: anterior to the medulla * sylvian cistern: superficial to the insular cortex

Answer 108

The olfactory nerve (I) is the cranial nerve responsible for olfaction. It is the shortest of the cranial nerves. **Function:** Special sensory – olfaction **Location:** Roof of the nasal cavity

Answer 109

The olfactory nerve is a collection of nerves extending from the olfactory epithelium to the olfactory bulb via the dura mater and many small perforations of the cribriform plate (of the ethmoid bone). The olfactory bulb and tract are an extension of the central nervous system. It contains second order olfactory neurons. The olfactory bulb and tract pass posteriorly in the olfactory sulcus of the frontal lobe and the olfactory groove of the anterior cranial fossa. It divides into medial and lateral stria (anterior to the anterior perforated substance): * The lateral stria synapse at the primary olfactory cortex * The medial stria crosses the anterior commissure It is the only sensory modality which is not relayed to the thalamus prior to synapsing at the cortex.

Answer 110

**Arterial:** ACA **Venous:** Cavernous sinus

Answer 111

* Superior: olfactory sulcus, anterior frontal lobe * Inferior: cribiform plate, olfactory mucosa * Medial: crista galli/flax, gyrus rectus * Lateral: Medial orbital gyrus * Anterior: Frontal sinuses * Posterior: Suprasellar cistern

Answer 112

The optic nerve is the second cranial nerve. **Function:** Special sensory – vision, carries visual information from the retina to optic radiations

Answer 113

Extension of the CNS with associated extension of the dura and CSF space. Dividable into 4 segments: * Intraocular – within the retina * Intraorbital – within the orbit * Intracanalicular – exits through the tendinous ring runs through the optic canal superior to the ophthalmic artery * Intracranial – Runs the suprasellar cistern meeting at the optic chiasm Nasal fibres decussate at the optic chiasm, temporal fibres do not. 2 optic tracts leave the chiasm coursing around the cerebral peduncles to the lateral geniculate body of the thalamus. Superior (superior retina) and inferior (inferior retina) bundle arise from the lateral geniculate bodies. Superior bundle -\> superior calcarine sulcus. Inferior bundle to the inferior.

Answer 114

Ophthalmic artery (and central retinal artery) ACA and superior hypophyseal artery

Answer 115

Optic chiasm: Posterior: the pituitary infundibulum and mamillary bodies Superior: anterior perforated substance, hypothalmus Lateral: middle cerebral arteries Inferior: sella turcica, pituitary gland

Answer 116

1 – nerve adjacent to the sphenoidal sinus 2 – Nerve compresses the wall of the sphenoid sinus 3 – nerve courses through the sphenoid sinus 4 – lateral to the sphenoid and posterior ethmoid

Answer 117

The third cranial nerve. **Function:** motor to the extra-occular muscles except lateral rectus and superior oblique, parasympathetic to the ciliary ganglion. Motor to the levator palpebrae superioris.

Answer 118

**Origin:** Medial aspect of the cerebral peduncles, (from the oculomotor nucleus anterior to the periaqueductal grey and the Edinger-Westphal nucleus – parasymp to ciliary ganglion). In the basal/interpeduncular cistern. **Course:** * Between the posterior cerebral artery and the superior cerebellar artery * Enters the cavernous sinus (most superior structure) * Enters the orbit via the superior orbital fissure **Divides into:** * Superior division: runs above the optic nerve gives branches to SR and lavator palpabre superioris. * Inferior division: parasymp. To ciliary ganglion and the extraocular muscles except SO,LR,SR

Answer 119

**Arterial:** opthlamic artery **Venous:** Superior ophthalmic vein

Answer 120

Origin is superior to the pons Runs between the posterior cerebral and superior cerebellar arteries Most superior nerve in the lateral wall of the cavernous sinus, above trochlear Enters the orbit within the tendinous ring

Answer 121

Origin may vary Relation to arteries may vary

Answer 122

The fourth cranial nerve. **Function:** Motor to superior oblique

Answer 123

Smallest diameter cranial nerve Longest intracranial length Only nerve to emerge posteriorly **Divided into:** * Intraparenchymal portion * Cisternal portion * Cavernous portion * Orbital portion **Origin:** trochlear nucleus, decussates, exits below the inferior colliculus **Course:** * cisternal portion course through the ambient cistern, runs between the superior cerebellar artery and the posterior cerebral artery lateral to the oculomotor nerve * Cavernous portion pieces the dura posteriorly and courses through the lateral wall of the cavernous sinus * Enters the orbit through the superior orbital fissure outside of the tendinous ring * Orbital portion arches up and medially above superior rectus and superior levator palpebrae to innervate the superior oblique

Answer 124

**Arterial:** Ophthalmic artery **Venous:** Ophthalmic vein

Answer 125

* Origin inferior to the inferior colliculus * Runs between the superior cerebella and posterior cerebral arteries lateral to oculomotor * Runs beneath the oculomotor nerve and above the ophthalmic nerve in the wall of the cavernous sinus

Answer 126

The fifth cranial nerve **Function:** Sensory information from the face, head and 2/3 anterior tongue and motor to the muscle of mastication plus mylohyoid (chin/jaw to hyoid) and tensor palatini.

Answer 127

**Origin:** Three sensory and one motor nuclei of the trigeminal nerve within the brain stem Exits at the lateral aspect of the pons **Course:** Anterior through the pre-pontine cistern Enters Meckel’s cave forming the trigeminal ganglion **Dividing into:** * Ophthalmic division * Maxillary division * Mandibular division

Answer 128

**Course:** * Through the lateral wall of the cavernous sinus * Branches through the superior orbital fissure **Branches:** * Fronatal * Lacrimal * Nasociliary **Supplies:** Sensation to the upper 1/3 of the face and cornea

Answer 129

**Course:** * Through the lateral wall of the cavernous sinus * Through the foramen rotundum into the pterygopalatine fossa **Branches:** * Zygomatic * Infraorbital * Greater and lesser palatine **Supplies:** Sensation to the middle 1/3 of the face

Answer 130

**Course:** * Through the foramen ovale **Branches:** Anterior and posterior divisions **Supplies:** * Muscles of mastication * Sensation to the lower 1/3 of the face and TMJ

Answer 131

The abducens nerve is the 6^th cranial nerve. **Function:** motor to the lateral rectus

Answer 132

**Divided into 4 parts:** * Intraparynchymal * Cisternal * Cavernous * Orbital **Origin:** Abducens nucleus, exits at the pontomedullary junction medial to the facial nerve **Course:** * Ascending in the pre-pontine cistern between the pons and the clivus * Through Dorello’s canal * Pierces the dura inferior to the posterior clinoid process * Cavenous portion runs within the cavernous sinus between the internal carotid and the lateral wall * Enters the orbit through the superior orbital fissure within the tendinous ring **Terminates:** Lateral rectus

Answer 133

**Artery:** Ophthalmic artery **Vein:** Opthalmic vein

Answer 134

* Origin is medial to the facial nerve origin * Runs in the cavernous sinus between the internal carotid is medial and the trochlear nerve is lateral * Enters the orbit within the tendinous ring

Answer 135

The facial nerve is the seventh cranial nerve **Function:** Motor to the muscles of facial expression, stapedius, taste to the anterior 2/3 of the tongue and parasympathetic to lacrimal, sublingual and submandibular glands.

Answer 136

**Nuclei:** Facial nerve nucleus, superior salivary nucleus, solitary nucleus **Origin:** emerges from the pontomedullary junction lateral to the abducens nerve **Segments (I must learn to make expressions):** * Intracranial – joined by nervus intermedius, travels in the cerebellopontine angle cistern * Meatal – Anterior superior quadrant of the internal auditory canal, above the falciform crest and anterior to Bill’s bar * Labyrinthine – courses superior to and between the cochlear and vestibule in the fallopian canal, terminates at the geniculate ganglion at the anterior genu * Tympanic – Passes posterior from the genu in the medial wall of the middle ear. Second genu posterior to the pyramidal eminence passing down into the mastoid segment * Mastoid – descending in the medial wall of the aditus ad antrum of the mastoid in the fallopian canal exiting via the stylomastoid foramen. Chorda tympani arises here (taste and secretomotor). * Extracranial: * Passes between the posterior belly of the digastric muscle and the stylohyoid muscle * Enters the parotid gland between the deep and superficial lobes, dividing into 5 branches

Answer 137

* Temporal * Zygomatic * Buccal * Mandibular * Cervical

Answer 138

* Labyrinthine * Superficial petrosal * Stylomastoid arteries

Answer 139

The eight cranial nerve. **Function:** Innervation to the cochlea (hearing) to the vestibule (acceleration)

Answer 140

**Origin:** Most lateral of the pontomedullary junction nerves **Course:** Passes lateral through the cerebellopontine angle to the internal acoustic meatus **Divides into:** * Cochlear nerve * Superior and inferior divisions of the vestibular nerve * Nerve from the posterior semicircular canal Divided in the internal acoustic meatus by Bill’s bar and the falciform crest Cochlear nerve – sensory from the spiral ganglion **Vestibular nerve:** * Superior div. – sensory from the superior and lateral semicircular canals and the urticle * Inferior div. – sensory from the saccule * Nerve from the posterior semicircular canal – as the name suggests

Answer 141

Origin is lateral to the origin of nervus intermedius and the facial nerve

Answer 142

**Arterial supply:** Labyrinthine artery **Venous drainage:** Labyrinthine vein

Answer 143

The ninth cranial nerve **Function:** * Sensory to the tonsils, pharynx, middle ear and posterior third of the tongue * Taste from the posterior third of the tongue * Sensory from the carotid bodies * Parasympathetic to the parotid gland via the otic ganglion * Motor to stylopharyngeus

Answer 144

**Origin:** lateral medulla from the post olivary sulcus **Nuclei:** * Inferior salivary nucleus * Solitary nucleus * Glossopharyngeal nucleus **Course:** * laterally across the flocculus * Leaves the skull through the pars nevosa of the jugular foramen * Presents two ganglia superior and inferior * Passes between the internal jugular vein and internal carotid artery * Descends anterior to the internal carotid artery beneath the styloid process * At the lower border of stylopharyngeus it turns forward and forms an arch on the middle pharyngeal constrictor muscle * Passes under hyoglossus * Terminates at the palatine tonsils

Answer 145

Too many cats please train (the) little shits * Tympanic * Muscular * Carotid * Pharyngeal * Tonsillar * Lingual * Sinus

Answer 146

* Origin is superior to the vagus origin * Pars nervosa is the anterior part of the jugular foramen

Answer 147

The 10^th cranial nerve. Latin for wandering nerve due to its long wandering course. From brain to the abdomen. **Function:** Bulk of the parasympathetic to the gastrointestinal system and heart. Complex mixed sensory, motor and parasympathetic nerve.

Answer 148

**Origin:** Multiple rootlets from the posterolateral sulcus of the medulla **Nuclei:** * Nucelus ambiguous * Dorsal vagal nucleus * Solitary tract * Spinal trigeminal nucleus

Answer 149

* Travels around the medulla * Exits the skull via the pars vascularis of the jugular foramen * Presents superior and inferior ganglia * Descends in the carotid sheath between the internal jugular vein and internal/common carotid * Passes anterior to the subclavian arteries to enter the superior thoracic outlet * Both sides descend in the lateral aspects of the mediastinum posterior to the hilum of the lungs * Both nerve enter the abdomen through the oesophageal hiatus * The left nerve becomes the anterior vagal plexus * The right nerve becomes the posterior vagal plexus

Answer 150

* Auricular nerve * Pharyngeal nerve * Carotid body branches * Superior and recurrent laryngeal nerves * Superior and inferior cardiac nerves * Anterior and posterior bronchial nerves * Oesopheal, coeliac and hepatic plexi

Answer 151

* Origin is below the origin of the glossopharyngeal nerve * The pars vascularis is the posterior part of the jugular foramen * Runs anterior to scalenus anterior and posterior to sternocleidomastoid

Answer 152

The spinal accessory nerve, also called accessory nerve, is the eleventh cranial nerve (CN XI) and is composed of two parts, the cranial part and the spinal part. **Function:** motor to trapezius and sternocleidomastoid

Answer 153

**Cranial part:** * Fibre arise from cells of the nucleus ambiguous and emerge from either side of the medulla below the Vagus nerve * It runs anterior and joins the spinal portion * Passes through the jugular foramen * Separates from the spinal portion and joins the Vagus at the ganglia nodusum * Probably contributes to innervation of the uvula and levator vei palatine

Answer 154

* Fibre arise from the ventral horn between C1 to C5 forming a trunk * The trunk ascends entering the skull through the foramen magnum join the cerebral part to exit via the jugular foramen * Leaves the cranial part * Descends behind SCM * Pierces SCM giving innervation * In the posterior triangle it forms a plexus with the cervical nerves innervating the trapezius

Answer 155

**Arterial:** Branches of the vertebral arteries Ascending cervical Dorsal scapula **Venous drainage:** Clival venous plexus Internal jugular Dorsal scapula

Answer 156

The 12^th cranial nerve. Paired bilateral motor nerves. **Function:** * Meningeal branches innervate the dura of the posterior cranial fossa * Supply motor to all the muscle of the tongue except for palatoglossus (supplied by vagus).

Answer 157

**Origin:** Emerges from the medulla laterally between the pyramid and olive as a number of rootlets **Course:** * Rootlets join to form two roots on each side * The two roots leave the cranial fossa passing anteriorly through the hypoglossal canal located between the occipital condyle and the jugular tubercle of the occipital bone * The roots join to for a single nerve within the canal on each side * C1 branches join with the nerve at this point * Passes between the internal jugular and the internal carotid artery * The occipital artery loops around it * It then runs anterior, lateral to the lingual artery * Gives of branches when it reaches hyoglossus

Answer 158

**Arterial supply:** * Lingual artery **Venous drainage** * Internal jugular vein * Lingual veins

Answer 159

* Origin is between the olive and the pyramid, inferior to the vagus origin and superior to the spinal accessory origin * The hypoglossal canal is superior to the occipital condyles * Nerve runs anteriorly lateral to the lingual artery

Answer 160

* Medulla oblongata is the most caudal part of the brainstem and is between the pons inferiorly and spinal cord superiorly * Contains the vital autonomic cardiovascular and respiratory centers controlling heart rate, blood pressure, and breathing * Medulla is separated into two main parts: * ventral medulla which contains the olive, pyramidal tracts, and CN 9-12 rootlets * tegmentum (dorsal) medulla which contain the CN nuclei and white matter tracts * Ventral medulla * pyramids are paired structures located at the medial aspect of ventral medulla and flank the anterior median fissure * contains the the corticospinal tracts * corticospinal tracts decussate * olivary bodies are paired structures located at lateral aspect of ventral medulla * separated from the pyramids by an anterolateral sulcus * also a post-olivary sulcus lateral to the olivary bodies * olivary bodies contain the superior and inferior olivary nuclei * anteriorly there is an anterior median fissure * Dorsal medulla * posterior median sulcus and more lateral posterolateral sulcus * between these sulci are the fasciculus gracilis and nuclei forming gracilis tubercle at the midline * fasciculus cuneatus and nuclei forming cuneate tubercle more laterally * superior dorsal aspect of medulla forms the floor of the inferior 4th ventricle * inferior cerebellar peduncle * inferiorly surrounded by the cisterna magna * Embryology: myelencephalon aspect of the rhombencephalon (or hindbrain) becomes the medulla

Answer 161

Anterior: basilar part of the occipital bone Posterior: 4th ventricle, cerebellum, cisterna magna Hypoglossal nerve rootlets arise anterior to the olive Glossopharyngeal, vagus and accessory nerve fibres emerge posterior to the olives CN 6-8 arise between pons and medulla

Answer 162

Arterial supply: * Anterior: vertebral arteries, anterior spinal artery * Posterior: PICA Venous drainage: * Anterior: inferior petrosal sinus * Posterior: occipital sinus

Neuro Flashcards

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