Cerebro vascular lesions
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Transcript of Cerebro vascular lesions
Cerebro-vascular disease Cerebro-vascular disease
Brain Brain ImagingImaging
Dr. ABD ALLAH Dr. ABD ALLAH NAZEER. MD.NAZEER. MD.
Vallecula
4th Ventricle
Medulla Oblongata
Cisterna Magna
4th Ventricle Cerebellar Hemispheres Vermis
Post. Fossa level
Pones
Middle Cerbellar Peduncle
Prepontine Cistern
Ambean Cistern
Basilar Art.
Cerebellar Folia Quadrigeminal
Cistern
Midbrain
Aqueduct of Sylvius
Posterior fossa level
Pons
Medulla
Ventricular anatomy
Quadrigeminal Cistern
Occipital horn, Calc. pineal body
Quadrigeminal Cistern
Head of caudate Lentiform nucleus Thalamus
Internal Capsule
External Capsule
3rd Ventricle
Insula
Basal Ganglia
Vellum interpositum
Retro-thalamic Cistern
Retro-thalamic Cistern
Sup.cerebellar Cistern
Quadrigeminal Cistern
Pineal body
Inter. Cerebr. veins
Pineal bodyInter. Cerebr. veinsVein of
Galen
Retro-thalamic Cistern
Septum Pleusedum
Body of caudate
F
O
F
P
F
T
O
F
P
O
P
P
T T
F
O
Supra-ventricular level
P PP
F
CT Vascular Anatomy
ICA
ACA (a1)
ACA (a2)
MCA A. Communicating A.
Basilar A.
PCA
P. Comm. A.
Strong magnetic field andStrong magnetic field and
Radiofrequency (RF) coilsRadiofrequency (RF) coils
Imaging are created by the motion of hydrogen protons in Imaging are created by the motion of hydrogen protons in response to the applied radiofrequencyresponse to the applied radiofrequency
Multiplanar imaging [ Multiplanar imaging [ axial, sagittal, coronal axial, sagittal, coronal ]] Any MR examination should include T1 and T2 Weighted Any MR examination should include T1 and T2 Weighted
images images
BRAIN MRI
Cerebral lobesCerebral lobes
Sulci and gyriSulci and gyri
Brodmann AreasBrodmann Areas
Axial, Axial, Sagittal Sagittal and Coronal and Coronal MRI MRI AnatomyAnatomy
MRI Vascular Anatomy
Normal venous sinus anatomy
CT & MRI Terminology
Hypodense= Less dense = Hypointense on MRI.
Hyperdense= more dense= Hyperintense on MRI.
Isodense= of equal density= Isointense on MRI.
Infarction Hemorrhage ?!
Hypo dense Hyper dense Isodense
Hypo intense Hyperintense Isointense
CT density [HU](AV).Brain Parenchyma 30 - 40 HU
Hypo dense Normal brain 30-40 HU
CSF 0 -15 HU Brain edema 20 HU
Infarction 25 HU Cyst ? Content
Fat > -10 to -150 HU Air - 2oo HU
Infarction
SOL
Cyst
Infarction
Is a hypo dense lesion Is not a SOL Hyperacute, Acute , Subacute
or chronic Has a vascular territory Has a cortical distribution Account for 80 % of stroke
cases.
Infarction phase?!
Acute
subacute Chronic
Infarction with edema
Infarction with volume loss
Infarction phase?!
Acute
subacute Chronic
Infarction with edema
Infarction with volume loss
Hyperacute finding:Visualization of the clot within the vessel.
Hyperacute and acute finding:
Acute infarction
Acute infarction
Acute One Day Old Infarction Involving the Right Middle Cerebral Artery (MCA) Territory
Acute infarction
Acute infarction with left MCA occlusion
CT study of Brain shows faint low attenuation involving right insular cortex and adjacent basal ganglia - insular ribbon sign. Faint T2 hyperintensity seen on FLAIR. DW images show an obvious infarct with restricted diffusion, seems to be an acute infarct as changes are not marked on FLAIR and CT study. Area of involvement is larger on DW compared to FLAIR, a FLAIR - Diffusion Mismatch.
T2WI
DWI
Subacute infarcts 3 weeks after stoke
Chronic infarction Hypodense lesion Loss of volume ( gliosis) negative mass effect on the ventricle and sulci [Evacuee dilatation]
Porencephaly
Hemorrhagic infarction
Venous thrombosis Arterial embolism
Infarction with hemorrhagic foci
Two main causes :
Hemorrhagic infarction
Chronic white matter leukoencephalopathy Chronic white matter leukoencephalopathy (low grade ischemia)(low grade ischemia) White matter ischemic changes diffuse hypo density Hypertensive, diabetic patients
White matter leukoencephalopathy
Lacunar infarctions , Lacunar infarctions , 2 CasesCases
Young age
Close to the ventricles
Perpendicular to the ventricle
High signal in PD or FLAIR
Enhancement of active lesions
Clinical picture
MS PLAQUES
MS PLAQUES with active stage
Calvarial bones
epidural
Subdural
Subarachnoid
Intra-cerebral
Intra-ventricular
Account of 20 % of strokes.
Acute hematoma ( Hyperdense)
Subacute hematoma ( Isodense)
Chronic hematoma ( Hypodense)
Intracranial Intracranial hemorrhagehemorrhage
Anatomic Anatomic localizationlocalization
Extra axial hematoma = blood extending along the inner skull table = hemorrhage outside the brain parenchyma
Extra axial hemorrhage ( epidural or subdural) Subarachnoid hemorrhage
Intra axial hematoma = hemorrhage inside the brain parenchyma
Subarachnoid Hemorrhage
Rupture of an anterior Communicating artery Rupture of an anterior Communicating artery aneurysmaneurysm
Subarachnoid Hemorrhage
Bilateral subarachnoid Hemorrhage
Subarachnoid Hemorrhage at MRI FLAIR images
Subarachnoid Hemorrhage at MRI images
Subdural hematoma Concave inner margin Do not cross midline
Can be acute, sub acute or chronic.Can cross the sutures.
Epidural hematoma
Convex inner marginCan cross midline
Almost always acute.Cannot cross sutures.
Epidural HematomaEpidural Hematoma
Convex inner margin Almost always acute
Post traumatic
Epidural Epidural HematomaHematoma
Epidural Epidural HematomaHematoma
Subacute epidural Subacute epidural HematomaHematoma
Subdural Subdural HematomaHematoma
Concave inner margin Can be acute , subacute or chronic Usually seen in elderly patient History of minor trauma Can occur in the interhemispheric fissure
AcuteAcuteChroniChronic c
SubacutSubacutee
Subacute hematoma Subacute hematoma with sedimentation, with sedimentation, upper hypodensity and upper hypodensity and lower hyperdensitylower hyperdensity
Subacute hematoma with Subacute hematoma with re-bleeding, with hypo and re-bleeding, with hypo and hyperdensity blood hyperdensity blood component component
Subacute subdural Subacute subdural HematomaHematoma
Subacute subdural Subacute subdural HematomaHematoma
Intracerebral hematomaIntracerebral hematoma
Post-traumatic
Hemorrhagic Contusion
Right intra-cerebral hematoma
Figure 1: MRI brain (a) and (b) Axial clear T1WI and T2WI showing a large right temporal hetero-intense lesion which is predominantly isointense on T1WI and T2WI and it has a peripheral zone that is hyperintense on T1WI and T2WI suggestive of acute clot. (c) MRI with GADO showing enhancement of the dural-based lesion along the temporal convexity
Intracerebral Intracerebral hematomahematoma
Intra-cerebral and intra-ventricular Intra-cerebral and intra-ventricular hematomahematoma
Acute Hematoma [Deoxy – Hb]Low signal T1 WI More low signal in T2 WIs
CT
Subacute Hematoma [Met – Hb]High signal T1 WIs High signal in T2 WIs
Intracerebral hematoma Intracerebral hematoma subacutesubacute
Hyper-acute Hematoma
Intra-cerebral and intra-ventricular Intra-cerebral and intra-ventricular hematomahematoma
Cerebral Cerebral contusioncontusion
Diffuse axonal Diffuse axonal injuryinjury
Dural sinus thrombosis
Dural sinus thrombosis
Dural sinus thrombosis
Q1, Case. M. EN. Q1, Case. M. EN. PP
Q2, Case. Q2, Case. EPHEPH
Q3, Case. SDH e cal.Q3, Case. SDH e cal.