Neuroimaging Flashcards
How to classify intracerebral hemorrhage?
Primary hemorrhage: hypertensive hemorrhage, lobar hemorrhage secondary to cerebral amyloid angiopathy
Secondary hemorrhages: ischemic stroke, cerebral venous thrombosis, vascular malformation, tumor (primary or secondary)
What CT features can predict the likelihood of intracerebral hemorrhage expansion?
- Hemorrhage size
- Hemorrhage shape: regular or irregular
- Hemorrhage density: hypodense/isodense regions within the hyperdense intracerebral hemorrhage represent active bleeding and is called swirl sign. When swirl sign is encapsualted it is termed black hole sign. Presence of relatively hypodense area adjacent to a hyperdense area is termed the blend sign
- Intraventricular hemorrhagic extension: due to compression of the hemorrhage into the low resistance ventricular system, thus; haematomas located in the thalamus, caudate nucleus or pons are more prone to intraventricular extension than lobar haematomas
What points should be included in CT report of intracerebral hemorrhage?
- Location
- Size/volume: ABC/2 formula
- Shape (irregular vs regular)
- Density (homogenous vs heterogenous)
- Presence/absence of subsantial surrounding edema that may indicate an underlying tumor
- Presence/absence of intraventricular hemorrhage
- Presence/absence of hydrocephalus
- When CT angiography is performed, the presence/absence of the CTA spot sign or a vascular malformation
dx?
Vascular lesion causing these hemorrhages?
What is the common underlying cause of these types of hemorrhage?
Non-contrast CT of the brain demonstrates an acute intracerebral haemorrhage centred in the basal ganglia of the left hemisphere. There is extension into the left lateral ventricle (intraventricular haemorrhage), with blood-forming a cast of the lateral ventricle, and passing into the third ventricle. There is no hydrocephalus at this stage.
Basal ganglia hemorrhage
Charcot Bouchard microaneurysms
Chronic poorly controlled hypertension?
What complications?
How to manage patient?
What are the indications for surgical intervention?
Cerebellar hemorrhages are often complicated by hydrocepahlus, brainstem compression, and/or cerebellar herniation
* Surgical craniotomy +/- extraventricular drain (if needed for hydrocepahlus) is often recommended
Indications for surgical intervention
* Neurological deterioration
* Brainstem compression
* Obstructive hydrocephalus
* Cerebellar ICH volume >15ml
Large right frontal lobe hyperdense lesion with marked mass effect with extension into the right frontal horn which is displaced across the midline. Sulcal effacement on right hemisphere.
What classical CT sign seen below?
This is the swirl sign. It represents unclotted fresh blood which is of lower attenuation than the clotted blood which surrounds it.
Very large left-sided extradural haematoma which underlies the parietal bone and the occipital bone with fracture diastasis of the left lambdoid suture. There is marked midline shift to the right and compression of the midbrain due to uncal herniation. Left cerebellar tonsil descends through the foramen magnum without causing compression of the cervicomedullary junction.
Petrous temporal fracture accounts for locules of intracranial gas within the haematoma.
This is the black hole sign. Centrally within the hyperdense haematoma is a well defined area of hypoattenuation not connected with the surrounding brain parenchyma. It represents acute extravasation of blood into a haematoma.
Perihaematomal white matter edema + haematoma causing mass effect –> midline shift and sulcal effacement.
A right-sided parietal fracture with underlying bi-convex (lentiform) extradural haematoma.
Dx
Management
Crescentic hyperdense lesion over the right hemishere.
Initial resuscitation, systemematic assessment
Warfarin reversal with vit K and clotting factors
What is seen?
Hypodense lesion in the territory of left MCA without hemorrhagic transformation and no significant mass effect
