7-blood supply of the cns · •motor & somatosensory cortex (lower limb & perineum)...
TRANSCRIPT
![Page 1: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/1.jpg)
Blood Supply of the CNS
![Page 2: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/2.jpg)
Lecture Objectives
• Describe the four arteries supplying the CNS.• Follow up each artery to its destination. • Describe the circle of Willis and its branches.• Discuss the principle of end artery type of circulation.• Describe venous drainage of the brain.
![Page 3: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/3.jpg)
Vertebral Artery• Branch of the 1st part of the subclavian a.
• Ascends the neck through the upper sex transverse vertebrae
• Inters the skull through foramen magnum
• Both sides unit to form the basilar a.
![Page 4: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/4.jpg)
Vertebral Artery
• Branches• Meningeal aa.• Anterior spinal a. • Posterior spinal aa.• Posterior inferior cerebellar a.• Medullary aa.
![Page 5: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/5.jpg)
Basilar Artery
• Ascend in front of pons • Participate in forming circle of Willis
• Branches • Anterior inferior cerebellar aa.• Pontine aa.• Superior cerebellar aa.• Posterior cerebral aa. (end branches)• Inferior & posterior parts of cerebrum
![Page 6: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/6.jpg)
Blood Supply to CortexCircle of Willis
![Page 7: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/7.jpg)
Blood Supply to CortexVascular Territories
![Page 8: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/8.jpg)
Blood Supply to CortexVascular Territories
![Page 9: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/9.jpg)
Blood Supply to CortexVascular Territories
![Page 10: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/10.jpg)
Blood Supply to Deep Structures
![Page 11: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/11.jpg)
Internal Carotid Artery
• Ophthalmic a.• Posterior communicating a.• Anterior choroidal a.• Anterior cerebral a.• Middle cerebral a.
![Page 12: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/12.jpg)
Middle Cerebral Artery
• Language areas (left MCA in most people)• Motor & somatosensory cortex (except‐ lower limb & perineum)• Auditory cortex• Lenticulostriate arteries‐ basal gangila & internal capsule (genu)
![Page 13: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/13.jpg)
Middle Cerebral Artery
![Page 14: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/14.jpg)
Middle Cerebral Artery
![Page 15: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/15.jpg)
Anterior Choroidal Artery
• Hippocampus, uncus & amygdala• Choroid plexus (temporal horn of lateral ventricle• Globus pallidus, putamen, part of thalamus• Internal capsule (posterior limb)
![Page 16: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/16.jpg)
Anterior Choroidal Artery
![Page 17: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/17.jpg)
Anterior Cerebral Artery
• Motor & somatosensory cortex (lower limb & perineum)• Corpus callosum (except‐ splenium)• Olfactory bulb & tract• Recurrent artery of Heubnar
• Head of caudate (ventral part) and adjacent putamen• Internal capsule (anterior limb)
![Page 18: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/18.jpg)
Anterior Cerebral Artery
![Page 19: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/19.jpg)
Posterior Cerebral Artery
• Hippocampus• Parahippocampal gyrus• Calcarine branch‐ all primary & some association cortex for vision• Posterior choroidal artery
• Choroid plexus (lateral & 3rd ventricles)• Thalamus (posterior part)• Fornix• Tectum
![Page 20: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/20.jpg)
Posterior Cerebral Artery
![Page 21: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/21.jpg)
Blood Supply to SC• One anterior spinal a.
• Vertebral aa.• Two posterior spinal aa.
• Vertebral aa. 25%• PICA 75%
• Anterior & posterior radicular aa.• Arise at every spinal level• Serve their respective roots & ganglia
![Page 22: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/22.jpg)
Blood Supply to SC
• Anterior & posterior spinal medullary aa.• Arise at intermittent levels• Serve to augment the BS to SC
• Artery of Adamkierwicz• Unusually large spinal medullary a.
• Usually on the left• In low thoracic or upper lumber levels
![Page 23: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/23.jpg)
Blood Supply to SC• Spinal cord Ischemia• Anterior spinal a.
• Small & tenuous• Occlusion produces bilateral damage (below lesion)
• Affects• Corticospinal tracts
• Paraplegia below lesion• Spinothalamic tracts
• Thermoanesthesia and analgesia
• Descending autonomic tracts• Loss of bladder & bowel
control• Anterior gray horn
• Near enlargement – weakness of limb muscles
![Page 24: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/24.jpg)
Veins of the BrainSuperior cerebral veins → SSS
Superficial middle cerebral veins → cavernous sinus
Deep middle cerebral veinAnterior cerebralStriate veins
basal vein
Thalamostriate veinChoroid vein
Internal cerebral vein
Great cerebral vein↓
straight sinus
External cerebral veins Internal cerebral veins
![Page 25: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/25.jpg)
Veins of the Brain
![Page 26: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/26.jpg)
Veins of the Brain
![Page 27: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/27.jpg)
Dural Venous Sinuses
LocationDrains …..Fate• Superior sagittal sinus
• Venous lacunae• Inferior sagittal sinus• Straight sinus• Occipital sinus• Transverse sinus• Sigmoid sinus• Cavernous sinuses• Superior and inferior petrosal sinuses
![Page 28: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/28.jpg)
Dural Venous Sinuses
![Page 29: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/29.jpg)
Blood Brain Barrier
• protects cells from some toxins and pathogens• proteins & antibiotics can not pass but alcohol & anesthetics do
• Structure• tight junctions seal together epithelial cells
• continuous basement membrane• astrocyte processes covering capillaries
![Page 30: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/30.jpg)
Blood Brain Barrier
• Areas without BBB• Area postrema in the floor of the fourth ventricle
• Areas in the hypothalamus
• Structure• Endothelial fenestrations
![Page 31: 7-Blood Supply of the CNS · •Motor & somatosensory cortex (lower limb & perineum) •Corpus callosum (except‐splenium) •Olfactory bulb & tract •Recurrent artery of Heubnar](https://reader033.vdocuments.mx/reader033/viewer/2022041807/5e5571658a039528ab5d4079/html5/thumbnails/31.jpg)
Blood Cerebrospinal Fluid Barrier
• Structure• Endothelial cells• BM of endothelial cells• Pale cells• BM of choroidal epithelial cells• Tight junctions seal the choroidalepithelial cells