正常颅脑CT及MRI影像表课件

正常正常颅脑CT及及MRI影像影像表表正常颅脑CT及MRI影像表正常颅脑CT及MRI影像表正常颅脑1NORMAL ANATOMY OF BRAINBrain is separated from calvarium by three meninges-dura mater,arachnoid membrane and pia mater.Divided into supra tentorial and infra tentorial compartments containing:-Supratentorium:Cerebral hemispheres diencephalonInfratentorium:Brain stem structures cerebellum Each cerebral hemisphere is further divided in to Frontal,Parietal,Temporal and Occipital lobes by fissures NORMAL ANATOMY OF BRAINBrain i2BRAIN ANATOMYBRAIN ANATOMY3Sagittal surfaceLat vent GenuFornixPituitary gland Mid brainPonsMedullaCingulate gyrusQuadrigeminalcisternSpleniumColliculi4th ventCerebellumThalamusSagittal surfaceLat vent GenuF4Sagittal surfacei.Pineal glandii.Inf.Colliculiiii.Aqueduct of sylviusiv.Midbrainv.Cerebellumvi.4th ventriclevii.Ponsviii.Oculomotor nix.Inter thalamic commissure109Sagittal surfacePineal gland105Inferior surfaceInterhemispheric fissureTemporal lobe Mammillary bodies Frontal lobeOlfactory tractOptic tractPit.stalkponsMedulla oblongataCerebellumVermisInferior surfaceInterhemispher6Brain stem structuresMid brain:divided into Cerebral peduncles and colliculi.Sup colliculi attached to med.Geniculate&Inf to lateral Geniculate bodySurrounded by Peri-mesencephalic cistern.Pons:divided in to tectum and tegmentum Connects mid brain to medullaMedulla:continues as spinal cordContains ascending and descending Spinal tractsBrain stem structuresMid brain7CerebellumDivided into two hemispheres by falx cerebelliConnected in the midline by a worm like structure-VermisDivided into I.Anterior lobeii.Middle lobeIii.Flocculo-nodular lobeCerebellumDivided into two hem8Ventricles of brainLateral ventricle:-C shaped cavity with body in the parietal lobe and extensions in the frontal temporal,occipital lobesConnected to third ventricle by foramen of monro.Third ventricle:-lies b/w two thalami.connected to fourth ventricle by cerebral aqueduct.Fourth ventricle:-lies in the cerebellumCSF Flow:-Lat.vent-foramen of monro-3rd vent-cerebral aqueduct-4th vent-foramen of magindie and luschka-sub arachnoid space finally absorbed by the arachnoid granulationsVentricles of brainLateral ven9Ventricles of brainVentricles of brain10Blood supply of the brainBlood supply of the brain11Blood supply of the brain By Internal Carotid and Vertebral A Internal carotid A:Middle cerebral A Ant cerebral A Pmunicating A Ant.Choroidal A Vertebral As:-two Vertebral as join to form Basilar A Branches:Ant inf cerebellar A Sup cerebellar A Pontine As&labyrinthine As Post cerebral ABlood supply of the brain By I12Contd.Divides into cortical and perforating APerforating As supply Basal ganglia,Thalami,internal capsuleThalamus:-Perforating br of PCAInternal cap:-Med&lat striate br of MCA,recurrent br of ACA,Ant choroidal AMid brain:-Post.cerebral and Sup cerebellar APons:-Pontine br of Basilar ACerebellum:-cerebellar A,Post inf cerebellar AMedulla:-Ant&Post spinal A,PICAContd.Divides into cortical a13Blood supply of the brainRed:-MCABlue:-ACAGreen:PCABlood supply of the brainRed:-14Circle of willisCircle of willis15Venous sinuses of brainStraight sinusTorculaherophiliOccipital sinusTransverse sinusSup.Sagittal sinusInf.SagittalsinusVenous sinuses of brainStraigh16Venous sinuses.Transverse sinusStraightsinussigmoidsinusPitutiary glandICA3rd CN4th CN6th CNSphenoid boneVi Vii br Of 5th CNVenous sinuses.Transverse sin17Axial sectionCingulategyrusCaudateheadPineal glandCorpus callosumLentiform nucleustrigoneSup.cerebellar cisternThalamusAxial sectionCingulateCaudateh18Coronal sectionCoronal section19CT TechniquePatient is kept in supine position and head is placed in the gantry under the cursors.Axial sections are taken at an angle of 10-13 degree to the canthomeatal line.Slice thickness:-Posterior fossa:-5mmSupra tentorial structures:-10mmPituitary gland and sellar region:-1-3mm(coronal sections)CONTRAST STUDIES:done by injecting 100 ml of 60%iodinated contrast CT TechniquePatient is kept in20 contd.Normal enhancement:Arterial&venous structures Dural structures:-falx,tentorium Choroid plexus Pituitary glandIndications of CECT:I.Infections:ring enhancing lesions eg tuberculoma,neurocysticercosis,Meningitis,Encephalitis ii.Tumours:astrocytomas,meningiomas iii.Vascular lesions:aneurysms,AV malformationsContraindications of CECT:I.history of allergy,renal failure ii.acute haemorrage ;contd.Normal enhancement:21Axial sections-TopogramFor CT Axial sections are taken at an angle of10-13degree to the Canthomeatal lineFor MRI sections are parallel to the reference lineAxial sections-TopogramFor CT 22CT Brain contdNormal HU values in NCCT brainGray matter:-+36-42 HUWhite matter:-+26-34 HUCSF:-+4-11HUBone:-+200 to+1000 HUCalcification:-+100 to+220 HUBlood:-+56-80CT Brain contdNormal HU value23MRI ImagingMultiplanar modlity so sections can be taken in axial,coronal and sagittal planesSlice thickness is same as CT imaging.Routinely applied sequences are T1 Weigheted spin echo T2 Weigheted spin echo Proton density imagesAnatomy of brain is better explained on T1W seq while pathologies are better studied on T2W and Proton density sequences.MRI ImagingMultiplanar modlity24TISSUE CHARACTERISTICSSeq Parameters CSF Gray M WhiteM FatT1W short TR Hypo iso hyper hyper short TE T2W short TR hyper iso hypo iso/long TE hypoProton long TR iso Iso iso/hypo hyperdensity short TE blood vessels appear signal void in all the sequences calcification and fibrous tissue appear hypointense in all sequences TISSUE CHARACTERISTICSSeq P25MRI Axial section above foramen magnumMaxillary sinusBasilar A.MedullaCerebellar hemisphereCisterna magnaTonsilsPetrous boneSphenoid sinusNasal cavityZygomatic archMRI Axial section above forame26CT Axial section above foramen magnumFrontal sinusSphenoid sinusTemporal lobeBasilar A.Mastoid cellsCerebellar hemisphereCisterna magnaMedullaOptic nervePituitarySphenoid boneTemporal boneCerebellar tonsilsCT Axial section above foramen27MRI Axial Section at 4th VentricleLensOptic nervePituitaryTemporal lobeMiddle cerebellar peduncle4th VentricleMedial rectusLateral rectusPonsPetrous temporal boneCerebellar hemisphereMRI Axial Section at 4th Ventr28CT Axial section at 4th ventricleFrontal sinusFrontal boneMid.cerebral ABasilar A.Pons4th ventcerebellumMid cerebellarpedunclePetrous boneTemporal hornAnt.cerebral aSella turcicaVermisCT Axial section at 4th ventri29MRI Axial Section above 4th ventricleSuperior oblique musclePituitary stalkUpper ponsSuperior cerebellar peduncleOptic chiasmaAmbient cisternCerebellar foliaMRI Axial Section above 4th ve30CECT Axial section above 4th ventricle Frontal lobe Ant cerebral A.4TH ventCerebellum Pons Temporal hornInfundibulum Post.cerebral A.Sphenoid boneFrontal boneFrontal sinusMid.cerebral ACECT Axial section above 4th v31MRI Axial section at midbrainFrontal lobeInterpeduncularcisterninferiVermisInferior colliculiConfluence of sinusesAmbient cistern UncusOptic tractMid cerebralACerebral peduncleAnt cerebral AMRI Axial section at midbrainF32MRI Axial section at 3rd ventricleGenu of corpuscallosum Caudate head Lentiform nuleusThalamusSplenium of corpus callosumFrontal hornsInsula3rd ventricleOccipital hornsOptic radiationMRI Axial section at 3rd ventr33CT Axial section at 3rd ventricleGenu of corpus callosumCaudate nucleus3rd ventriclePineal glandvermisOccipital lobeChoroid plexusThalamusLentiform nucleusFrontal hornPericallosal ACT Axial section at 3rd ventri34MRI Axial section at mid ventricleCingulate gyrusBody of lateralventricleCorpus callosumCentral sulcusCorpus callosumInter hemisphericfissureMRI Axial section at mid ventr35CT Axial section at mid ventriclesCingulate gyrusBody of lateral ventricleCorpus callosumFalx cerebriOccipital hornsParietal lobeCorona radiataFrontal hornsConfluence of Sinuses(torcula)CT Axial section at mid ventri36MRI Axial section at centrum semiovaleInter hemispheric fissureCentrum semiovaleOccipital lobeParietal lobeFrontal lobeMRI Axial section at centrum s37CT Axial section at centrum semiovaleFalx cerebriCentrum semiovaleOccipital lobeParietal lobeFrontal lobeCT Axial section at centrum se38MRI Coronal section at 3rd ventricleFrontal hornsFornix3rd ventricleClivusInterpeduncularcisternInsulaSylvian fissureTemporal lobeParotid glandOdontoid(dens)MRI Coronal section at 3rd ven39MRI Coronal section at suprasellar levelInter hemispheric fissureLat ventricleLat.Pterygoid MsNasopharynxMed.Pterygoid Ms.Sylvian fissureSphenoid sinusPituitary glandOptic chiasmAnt cerebral aMid cerebral AMRI Coronal section at suprase40MRI Coronal section at post.ventricleParietal lobeSplenium of corpus callosumSup.cerebellar cisternTentoriumChoroid plexusAtria of lateral ventricle 4th ventricleMRI Coronal section at post.v41MRI Sagittal sectionLat ventGenu3rd ventSphenoid sinusNasopharynxBody of CCSpleniumQuadrigeminal cisternPons4th ventMedullaCerebellumTonsilCingulate gyrusPrepontine cisternMRI Sagittal sectionLat ventGe42CT Coronal section for Pituitary glandPatient is kept in prone position in sub mento vertical position,in the head rest of CT tableTopogram is taken in this position and planning is done so that cut sections parallel to the line passing from frontal bone to mentis is takenFor pituitary 1-3mm thick sections are taken in the coronal plane starting from anterior to posterior.CT Coronal section for Pituita43CT Coronal section for Pituitary glandLateral ventAnt.cerebral APituitary glandOptic chiasmSphenoid sinusLat.pterygoid plateNasopharynxLat.Pterygoid msMid.cranial fossaCT Coronal section for Pituita44CT Coronal section for Pituitary glandLat pterygoid plateSphenoid sinusMid.cerebral aAnt.cerebral aFrontal sinusInternal carotid aNasopharynxPituitary glandCT Coronal section for Pituita45CT Axial section(bone window)Petrous boneMastoid air cellsCarotid canalForamen ovaleSphenoid sinusBase sphenoidEustachian tubeExt.acoustic canalLambdoid sutureOccipital boneCT Axial section(bone window)46CT Axial sections(bone window)Ear ossiclesMastoid air cellscochleaInt.acoustic meatusAditus to antrum boneFacial n canalEthmoidal sinusCT Axial sections(bone window)47CT Axial sections(bone window)Occipital boneJugular foramenBase sphenoidSphenoid sinusExt.acoustic CMastoid air cellsCarotid canalGreater wing of sphenoidCT Axial sections(bone window)48CT SCAN-Why do it?Advantages of CT:I.Useful in diagnosis of intracranial bleed in acute head injury ii.Better demarcation of bony pathology iii Easy availability iv.Cost effective v.Less time consuming vi.Easy interpretationsDisadvantages of CT I.Poor demarcation between gray matter and white matter ii.Less effective in very early and very late haemorrage and infarct iii.Radiation hazardCT SCAN-Why do it?Advantages o49MRI Why do itAdvantages:Multiplanar modalityBetter gray and white matter differentiation or better spatial resolutionBetter for evaluation of posterior fossa structuresNo radiation hazardDisadvantages:Contraindicated in patients with claustrophobiaContraindicated in patients having aneurysmal clips,metal fillings if these are not MRI compatibleNot useful in evaluation of bony pathologies,calcificationsMovement sensitiveMRI Why do itAdvantages:50THANK YOU51汇报完毕谢谢大家!请各位批评指正汇报完毕谢谢大家!请各位批评指正52