Neuroradiology Flashcards
Which vessels cause this
Bridging veins. Subdural haemorrhage assumes a crescent shape. Acute looks bright, chronic looks same as brain. Most commonly from bridging veins in origin
Headache with previous falls
Subacute suburals –On the right there is a right subacute subdural and a left chronic subdural
Headahce
Sagital sinus thrombosis
Headache
Sagital sinus thrombosis
In the sagittal T1-weighted image, the normal flow void (low signal) is replaced by intraluminal high signal related to thrombosed superior sagittal sinus. The signal intensity of the thrombus over time has the same evolution pattern as intracerebral hematomas
Confusion
Alzheimers - temporal parietal atrophy
Confusion
FTD atrophy (used multiple times)
Frontotemporal dementia is the correct response. Frontotemporal dementia often is familial. Frontal and temporal atrophy as seen in the patient images are supportive features for diagnosis of frontotemporal dementia, though absence of atrophy does not exclude the diagnosis. Frontotemporal dementia is characterized by a strong gradient of atrophy from anterior to posterior along the temporal lobe, as seen in the patient images. In Alzheimer disease, atrophy occurs throughout the temporal lobe. Binswanger disease is characterized by subcortical foci of patchy T2 hyperintensities in white matter, a finding not seen in the patient images. Infarction typically has an acute onset of neurologic deficit and on imaging there will be a focal cortical defect. This patient had gradual dementia onset and no focal full thickness cortical loss. Herpes encephalitis is an acute febrile illness. Common early symptoms include change in consciousness (confusion, then stupor, then coma), fever, headache, and seizures. Inferior frontal lobe and medial temporal lobe involvement with edema, restricted diffusion and contrast enhancement in the acute phase, and tissue destruction later are usual findings. These are not features of the patient and her images.
Falls
PSP with hummingbird sign
Parkinsonism
MSA - hot cross bun sign
MSA
Discussion:
The MRI findings show the “Hot Cross Bun” sign in the pons, as well as hyperintensity in the cerebellar peduncles. These findings are most suggestive of multiple system atrophy, a neurodegenerative disorder. Parkinson disease, postencephalitic parkinsonism, and prolonged metoclopramide exposure typically would not have characteristic MRI findings. NPH would demonstrate enlargement of the ventricles along with transependymal flow.
Parkinsonism
MSA – C – pons, cerebellum, hot cross buns sign, big 4th vent
Parkinsonism
MSA - olivopontocerebellar atrophy
Child with Rett’s syndrome:
FT atrophy in kid – Rett syndrome
2017 RITE 50, headache, leg weakness
Vasculitis: beading of the vessels
Discussion:
The diffusion-weighted views demonstrate multiple focal areas of acute infarction. These involve both the deep gray and white matter along with scattered cortical areas of infarction. These regions of infarction are in a multifocal vascular distribution atypical for branch large vessel disease and similarly atypical for small vessel infarctions or a cardioembolic etiology, which tend to be cortical. An MRA scan of the head performed concomitant with the study illustrated demonstrated marked beading along numerous arterial structures typical of vasculitis. This is best seen and illustrated in Figure 3 on the conventional cerebral angiogram.
Arterial thrombus: Left vertebral artery Thrombus
Discussion:
The CT of the head demonstrates a hypo dense segment in the left cerebellum typical of an acute infarction, and the CTA axial view demonstrates a segment of decreased density within the left vertebral artery typical of a thrombus. The carotid and right vertebral artery are well demonstrated and are normal. A thrombus can occur due to atrial fibrillation, that would not be the only etiology. Similarly, trauma can result in a vertebral dissection, but again, that would not be the only possible etiology. The study demonstrates normal appearance on CT of the sigmoid sinus bilaterally and does not suggest a sigmoid sinus thrombosis. Similarly, subclavian steal is associated with posterior circulation symptoms or infarction; however, a segment of decreased density within the left vertebral artery is not the appearance seen with reversal of vertebral arterial flow.
DWI in HIV IVDU with 2/7 hx unwell. 52
Most likely dx bacterial abscess. High signal DWI with hypointense ADC shown =. This means – infarct or abscess.
Unwell, IVT for hyponatremia
Central pontine myelinolysis – concentrated, symmetric, noninflammatory demyelination within central basis pontis. CMP predisposition – alcoholism, liver disease, malnutrition hyponatremia. Na < 120 then aggressive IVT
8 year old. ALL. Acute mental state change. Given MTX 10 days prior. And now has recurrent pulmonary infections. What is going on? What is the implications?
MTX causes acute neurotoxicity with diffusion abnormalities indicating cerebral dysfunction but not necessarily overt structural injury to the cerebrum. Secondary demyelination or gliosis cannot be predicted on imaging. A single episode with DWI abnormalities should not necessarily prompt modification of chemo.
- R arm and leg weakness. DWI – Cause?
Left ACA stroke
Incidental finding
Epidermoid cyst – isointense T1, non-enhancing, but restricts like WOAH – looks like CSF on everything other than DWI where it restrics
Incidental finding
Epidermoid cyst
Young, headache, fever
Restricted fluid levels in ventricles, enhancement, pyogenic meningitis!
On the diffusion-weighted views, there are fluid levels within the cortical sulci and within the posterior horns of the lateral ventricles with increased signal and on the T1-weighted postcontrast views, there is a perimeter of dural enhancement. Intracranial hypotension can produce a similar appearance of the postcontrast T1 views of pachymeningeal enhancement. However, fluid with increased diffusion signal as seen in this study is not seen in conjunction with intracranial hypotension nor would would it occur in neurosarcoid or subarachnoid hemorrhage. The appearence is typical of pus as seen with a pyogenic meningitis, ventriculitis, or an empyema.
Post MI arrest
Diffuse cortical ischaemia
Post Asthma in ICCU what does it show
DWI MRI sequence shows (day 3) acute anoxic damage. It is hyperintense signal which follows the cortical convolutions, suggestive of cortical laminar necrosis, a hallmark of diffuse hypoxic injury. This can occur because of hypotension, CCF (generally watershed areas),
Diffuse hypoxic injury
The CT study demonstrates near complete loss of cortical sulcation and diffuse decreased density in all hemispheres including the cerebellum along with generalized edema. These changes are in no specific vascular distribution and are typical of a severe hypoxic insult. The relative increased density within the fissures is a manifestation of contrast to the severe hypodensity of the remainder of the brain. Petechial hemorrhage due to necrosis may also be present. There were, however, no imaging findings to suggest a primary subarachnoid hemorrhage. Lissencephaly would not be associated with marked mass effect and edema as seen in this study; nor would hypertension encephalopathy.
Homless and confused
Wernicke’s – bilateral medial thalami
Progressive confusion FI (2017 exam) but may not have been this exact picture
CJD – cortical ribboning
Discussion:
The correct answer is prion disease. There is restricted diffusion involving the left occipital and left lateral temporal cortices. This patient had sporadic Creutzfeldt-Jakob disease, a progressive neurodegenerative disorder resulting from misfolded prion proteins. The imaging abnormality does not respect vascular territories, making ischemic infarction unlikely. Hypoxic brain injury typically causes symmetric abnormalities. The limbic, or medial temporal, structures appear normal. Hashimoto’s encephalopathy more commonly results in lesions in the white matter and/or brain stem.
Progressive confusion
CJD
Progressive confusion
CJD – hockey stick sign
Young female, hearing loss and encephalopathy
Susacs: young to middle-age women that is clinically characterised by the triad of acute or subacute encephalopathy, bilateral sensorineural hearing loss, and branch retinal arterial occlusions. – if get this clinical stem think SUSACS!
There tend to be multiple, small white matter lesions which have a predilection for the corpus callosum
the roof of the corpus callosum is also frequently involved, rather than the callososeptal interface (which is more typical of multiple sclerosis), resulting in ‘icicle’ or linear ‘spoke’ lesions that look to hang from the roof of the corpus callosum 11
- Multiple sclerosis flare
Discussion:
Multiple, supratentorial and infratentorial lesions are seen, with 2 acute enhancing lesions. This is most consistent with an acute exacerbation of multiple sclerosis. Vasculitic and other autoimmune conditions may also have similar imaging features and further clinical and laboratory information would be needed to make this distinction. These images are not consistent with either ischemic or hemorrhagic stroke. No leptomeningeal enhancement is present in this study. Variant Creutzfeldt-Jakob disease (vCJD) is a rare prion disease typically seen in younger patients who present with rapidly progressive cognitive decline, visual disturbance and may have increased signal intensity lesions on FLAIR views in the bilateral posterior thalami (“pulvinar sign”).
Confusion
PRES: posterior predominant, bilateral and symmetric confluent white matter changes
Young adult, TIA presentation
CADASIL: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL)
- AD
- mutation on chromosome 19q12 involving the NOTCH3 gene,
- widespread confluent white matter hyperintensities 2
- relative sparing of the occipital and orbitofrontal subcortical white matter 2, subcortical U-fibersand cortex 3.
Leg weakness
ACA stroke
Frontal seizure
Focal cortical dysplasia
General features of focal cortical dysplasia include 4:
cortical thickening
blurring of white matter–grey matter junction with abnormal architecture of subcortical layer
T2/FLAIR signal hyperintensity of white matter with or without the transmantle sign
T2/FLAIR signal hyperintensity of grey matter
abnormal sulcal or gyral pattern
segmental and/or lobar hypoplasia/atrophy
Seizure
Focal cortical dysplasia
HIV patient, low CD4 count, unwell
PML, JC virus reactivation – confluent white matter change
HIV confused
FLAIR shows white matter hyperintense abnormal signal which is suggestive of PML. Rare, usually fatal virus, exclusively with severe immune deficiency.
Young, acute confusion
HSV encephalitits – temporal lobe prediliction
Confusion
HSV 1
Discussion:
The images show bilateral mesial temporal and hippocampal edema, and this and the clinical history supports diagnosis of herpes simplex encephalitis. This disease often leads to elevated RBC count in CSF due to hemorrhagic changes. JC Virus is seen in PML, a white matter disease. HTLV antibodies are seen in HTLV-associated Myelopathy/TSP. Elevated spirochete IgM levels can be seen in CNS Lyme Disease, which causes multifocal white matter lesions. Toxoplasmosis causes focal cerebritis rather than diffuse edema in the temporal lobes.
headache
Pineal tumor causing obstructive hydro with transependymal flow
35, visual defect, R sided loss, sleepy, weight gain, thirst. Enhancing meningeal thickening in the suprasellar area involving the left optic tract. CXR shows hilar lymphadenopathy. ? diagnosis
Sarcoid.
Suprastellar mass differentials SATCHMO
Sarcoid, aneurysm/ adenoma, teratoma / dermoid cyst, craniopharyngioma, hamartoma of tuber cinereum, meningioma and optifc nerve glioma.
Child to adult progressive motor and cognitive
Adrenoleukodystrophy:
X-linked inherited metabolic peroxisomal disorder characterised by a lack of oxidation of very long chain fatty acids (VLCFAs)
severe inflammatory demyelination of the periventricular deep white matter
posterior-predominant pattern and early involvement of the splenium of the corpus callosum
Infant to young adult psych and dementia
Metachromatic leukodystrophy: AR, lysosomal storage disorders,
Periatrial and frontal horns leukodystrophy with periventricular sparing resulting in tigroid pattern (stripe pattern)
Metachromatic leukodystrophy: stripe formation
Jewish infant, blind, mental retardation, big head
Canavan disease: Spongiform degeneration of white matter – or aspartoacylase deficiency – characterised by megalencephaly, severe mental and neurological deficits and blindness
MRI confirms the megalencephalic appearance and provides more detail of the white matter disease, which is typically diffuse, bilateral, and involving the subcortical U-fibers 4-8:
Jewish infant, blind, mental retardation, big head
Canavan
Infant, big head, seizures and neuro deterioration
Alexander disease: frontal predominance to white matter disease, big head
Infantile or adult: myoclonus, nystagmus, opsiclonus
Krabbe’s: globoid cells (hence the name) is characteristic of the disease.
The corticospinal tracts are typically most involved
It is caused by a deficiency of galactocerebroside ß-galactosidase, an enzyme that degrades cerebroside, a normal constituent of myelin. Cerebrosides accumulate in the lysosomes of macrophages within the white matter. This results in demyelination
Infantile or adult: myoclonus, nystagmus, opsiclonus
Krabbe’s – classic halo alternating hyper/hypo intensities
Early infancy: pendular eye movements, hypotonia, pyramidal weakness
Pelizaeus Merzbacher: near complete absence of expected low signal in supratentorial region- abnormal signal can either be diffuse or patchy
if there is patchy involvement, a characteristic tigroid appearance may be seen 5
may also show cortical sulcal prominence due to atrophy 4
white matter volume may be decreased 4
may also involve cerebellum and brainstem 4
Typically young childhood – ataxia, opthalmoplegia
Leigh disease: bilateral T2hyperintensity in brainstem, midbrain, medulla, thalami – involvement of cerebellum or cerebral cortex unusual.
Typically young childhood – ataxia, opthalmoplegia
Leigh: bilateral T2 enhanacement, symmetric
Stroke sounding presentation
MELAS: MELAS (mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes) is one of many mitochondrial disorders.
multifocal stroke-like cortical lesions in different stages of evolution (“shifting spread” pattern), crossing the cerebral vascular territories, and showing a certain predilection to the posterior parietal and occipital lobes.
MRI : chronic and acute infarcts involving multiple territories. Parieto occipital most common.
What is this?
Amyloid angiopathy
Recurrent presentations of Neuro dysfunction
MS
IVDU
Septic Emboli
Returned traveller: seizure
Neurocysticercosis: The disease is endemic in Central and South America, Asia and Africa. The perpetuation of this parasitic disease is related to poor sanitation and hygiene.
Vesicular: viable parasite with intact membrane and therefore no host reaction.
Colloidal vesicular: parasite dies within 4-5 years 1 untreated, or earlier with treatment and the cyst fluid becomes turbid. As the membrane becomes leaky oedema surrounds the cyst. This is the most symptomatic stage.
Granular nodular: oedema decreases as the cyst retracts further; enhancement persists.
Nodular calcified: end-stage quiescent calcified cyst remnant; no oedema.
Neurocysticercosis: The disease is endemic in Central and South America, Asia and Africa. The perpetuation of this parasitic disease is related to poor sanitation and hygiene.
Discussion:
Cysticercosis is the best response. Initial noncontrast CT shows small calcifications in cortex without edema. Two contrast enhanced CT images show intense ring enhancement with prominent surrounding edema. Thigh muscles have diffuse calcifications from dead Taenia solium (pork tapeworm) larval calcifications. Cryptococcosis does not produce calcified lesions
in the brain. Metastases which may cause multifocal involvement in brain is not best response because the patient has no primary neoplasm diagnosis and metastasis does not cause brain and muscular calcifications. D. (septic emboli) is not best response because brain and muscle calfication is not explained by this entity. E. (toxoplasmosis) is not best response because it doesn’t
cause the calcifications in brain and muscle, and in adults, it affects those who are immunocompromised.
NCC cyst causing hydro:
Subarachnoid/intraventricular
When in the subarachnoid space/interventricular, the the cysts typically do not have a visible scolex. In the basal cisterns they can be grape-like (racemose). The cysts are typically 1-2 cm in diameter 2. Usually the cysts are similar in signal intensity to CSF, although occasionally cyst fluid may somewhat differ 2.
In the ventricles, there is often (79%) 2 associated ventriculitis often leading to aqueductal stenosisand hydrocephalus 2.
Seizure
Hyperintense Scolex w/ NCC
HIV, unwell, fever and headache
Toxoplasmosis (used multiple times) – surrounding oedema, ring enhancement, isointense / difficult to see on T1
he infection most likely occurs once the CD4+ count has dropped below 200 cells/mm 3,6.
HIV, unwell, fever and headache
Toxo – surrounding oedema, ring enhancement
HIV - The infection most likely occurs once the CD4+ count has dropped below 200 cells/mm 3,6.
Discussion: sulfadiazone and pyrimethamine
Toxoplasmosis is caused by an obligate intracellular parasite Toxoplasma gondii. Patients who develop AIDS are at particularly
high risk of disseminated toxoplasmosis which most frequently involves the CNS. Toxoplasmosis is the most common focal mass
lesion in AIDS and it most commonly involves the basal ganglia.
80yr old. Hx cancer
Mets
- Hx breast Ca
Hemorrhagic mets – melanoma, renal cell, choriocarcinoma, thyroid, bronchogenic, breast
DDx? Most likely dx in 80 yr old with Bkgd Ca
Ring enhancing lesions. DDx tumour, abscess, metastasis, toxoplasmosis and lymphoma (in immunocompromised). Given hx ca = metastasis.
Young female, headache
Sarcoid- homogenous enhancement – leptomeningeal???
The enhancing, nodular, patchy, diffuse abnormalities shown are most characteristic of neurosarcoidosis. Toxoplasmosis produces inflammatory lesions, which may enhance but are rarely restricted to the gray matter, as in this case. Cerebrotendinous xanthomatosis is a white matter disease. Hemorrhagic encephalopathy typically shows areas of both low and high signal intensity and is not uniformly enhancing. The patient’s age and race are also suggestive of neurosarcoidosis
Young female, headache, seizure
Sarcoid – leptomeningeal enhancement
65, low grade fever, general headache (CT Contrast)
Abscess (ring enhancing lesion, most likely abscess given background history) DDx tumour, abscess, metastasis, toxoplasmosis, lymphoma
T1 (L), T2(R) -46, homeless, confused
Acute and subacute haemorrhage. MRI shows haemorrhage of blood at different stages with perihematomal oedema – main component is isointense – with some more hyperintense specks. Acute hemorrhage appears isointense on T1 and hypointense on T2. early subacute are hyperintense on T1 and hypointense on T2
Male, headache, better lying
Intracranial hypotension sagging penis
Extra line along dural edge
headache
Intracranial hypotension
Leptomeningeal carcinomatosis
Pilocytic astrocytoma
Cerebellar hemangioblastoma
The images depict a large mass within the right cerebellum. This is cystic, with a markedly enhancing nidus or mural nodule. The enhancement is predominately confined to the mural nodule and spares most of the perimeter. There is very mild adjacent vasogenic edema. A metastatic lesion or abscess would be unlikely to demonstrate a mural nodule, and they generally demonstrate a complete ring pattern of enhancement. This appearance can be seen in a setting of a pilocystic astrocytoma; however, this lesion is a frequent finding in youth and highly unlikely in a patient of this age. Medulloblastomas tend to arise in the midline along the margin of the fourth ventricle between the brain stem and cerebellum and not laterally as in this instance and would not have the cystic appearance with a mural nodule. An arteriovenous malformation frequently demonstrates an enhancing nidus with multiple vascular structures. The vessels in an AVM however, are significantly larger as compared to the capillary size vessels seen here. This lesion is also known as a capillary hemangioblastoma as was confirmed on pathologic examination.
Cerebellar hemangioblastoma
The images depict a large mass within the right cerebellum. This is cystic, with a markedly enhancing nidus or mural nodule. The enhancement is predominately confined to the mural nodule and spares most of the perimeter. There is very mild adjacent vasogenic edema. A metastatic lesion or abscess would be unlikely to demonstrate a mural nodule, and they generally demonstrate a complete ring pattern of enhancement. This appearance can be seen in a setting of a pilocystic astrocytoma; however, this lesion is a frequent finding in youth and highly unlikely in a patient of this age. Medulloblastomas tend to arise in the midline along the margin of the fourth ventricle between the brain stem and cerebellum and not laterally as in this instance and would not have the cystic appearance with a mural nodule. An arteriovenous malformation frequently demonstrates an enhancing nidus with multiple vascular structures. The vessels in an AVM however, are significantly larger as compared to the capillary size vessels seen here. This lesion is also known as a capillary hemangioblastoma as was confirmed on pathologic examination.
Ganglioglioma
GBM
Discussion:
There is a single, large infiltrative multicystic enhancing mass with vasogenic edema. This appearance is most frequently seen with a glioblastoma multiforme. No vascular structures are seen as expected in an arteriovenous malformation (AVM). An infectious process, such as toxoplasmosis and a metastasis, would more likely have a ring pattern of enhancement and not the large complex multicystic pattern seen here.
Headache
GBM
Headache
GBM
Lymphoma
Lymphoma
There is an ovoid homogeneously enhancing mass with adjacent vasogenic edema. A hemorrhage, hemorrhagic infarction or demyelinating lesion would not have this pattern of homogeneous enhancement. A giant aneurysm would not show this degree of edema. This pattern is most frequently seen with lymphoma.
Well
Meningioma
Fever
Abscess
- Abscess
Discussion:
The images demonstrate a multi-ring enhancing mass lesion within the left occipital lobe with marked adjacent vasogenic edema. The multi-ring masses have narrow, homogenously enhancing margins. There is marked increased diffusion signal within the masses. Marked increased signal on diffusion is more likely in an abscess as compared to a tumor. The extent of vasogenic edema and patterns of ring enhancement would also favor an infectious etiology. A subacute infarction can show luxury enhancement, which generally involves the cortical ribbon. The pattern of edema in an infarction is cytotoxic edema, not vasogenic as seen in this case. A cerebral abscess is the more likely consideration in this instance. The pathology confirmed Nocardia in this patient with diabetes.
Headache
Pituitary macroadenoma
The study demonstrates increased density within the pituitary fossa extending to the cavernous sinuses bilaterally with an expansive lesion, which is demonstrated on the FLAIR and T1 view areas of both increased and decreased signal. There is an ovoid mass throughout the suprasellar cistern compressing the optic chiasm. It appears as that of a large pituitary mass, likely a pituitary macro adenoma. There is a perimeter of increased T1 weighted signal in the non-contrast view. A compilation of these features would be that of hemorrhagic transformation i.e. pituitary apoplexy of the pituitary tumor mass. A pituitary tumor of this size can be expected to result in bitemporal hemianopia. However, in the absence of hemorrhagic transformation, one would not expect to the tumor’s presence to result in coma as seen with this patient. A colloid cyst would not be expected in this location and generally arises as an intraventricular lesion adjacent to the foramen of Monro in the third ventricle. A metastatic lesion within the sella would be in the differential of a tumor mass; however, again, it would not be the best clinical explanation for the patient’s clinical presentation of sudden coma.
Metastatic mass
What is it
Mucocele
On the coronal and axial CT views, there is a complete opacification of the right maxillary sinus. The lesion appears expansile. There is marked thinning and a dehiscence of the lateral wall of the right maxillary sinus. A posterior wall of the right maxillary sinus and upper right lateral wall appears thickened. These changes are consistent with an indolent, expansile mass typical of a mucocele. Mucoceles can become infected and result in an abscess.
Lytic lesions, from mets, not pagets
The bone density images depict multiple lytic lesions within both the inner and outer tables, resulting in a somewhat moth-eaten appearance throughout the calvarium. The tissue density views demonstrate a hyperdense tissues within the lytic lesions. Paget disease is a disorder with lytic and sclerotic changes. However, there is generally a widening of the trabeculae and relative bone enlargement within the skull. In addition, the lytic lesions would not be filled with a more homogenous tissue density as seen in this study.
Fibrous dysplasia results in a ground-glass appearance to the bone, often expansile, but can show homogenous sclerotic areas or cystic areas, none of which is present in this study. A focus of eosinophilic granuloma is a solitary lytic lesion seen in children and young adults. The pattern of these lytic lesions is typical of a metastatic malignancy, and in this case breast carcinoma
SAH
Mixed bleeds – trauma
The CT provided demonstrates hematomas within the right frontal region, along with subarachnoid hemorrhage overlying the right hemisphere. The pattern is typical of contusions which arise in the interface between the bone surfaces. In addition, there is an obvious right parietal soft tissue hematoma. This pattern of hemorrhage with contusion is not typical of an aneurysmal rupture, nor would encephalitis present with this pattern of intracranial hemorrhages and subarachnoid hemorrhage. There is evidence of subdural hemorrhage; however, no epidural hematoma is seen in this view.
Severe hypoxic insult
Hemimegalencephaly is a congenital anomaly in which one hemisphere shows thickened or duplicated cortex, myelination is excessive. Severe epilepsy and hemiparesis are commonly found. If epilepsy is uncontrollable, hemispherectomy may be indicated
Diffuse calcifications – congenital infection
- Suependymal giant cell astrocytoma
Calcifications and hamartomas from tuberous sclerosis
Discussion:
Subependymal giant cell astrocytoma is the best response. The calcifications are at the medial aspect of head of caudate nucleus
at foramen of Monro, the site where calcified subependymal giant cell astrocytomas arise in TS. Low attenuation cortical hamartomas also are visible at left frontal and both parietal lobes; this is very typical tuberous sclerosis. Cysticercosis forms cystic lesions. Fahr’s disease is not associated with cortical hamartomas. CO poisoning does not produce calcified basal ganglia lesions. Cryptococcus does not produce calcified lesions or cortical hamartomas.
headache
Venous thrombosis with bleed
Wilsons
There is symmetric high signal intensity involvement of the putamen and thalami bilaterally. The globus pallidus is also involved but not exclusively as it is in many patients with carbon monoxide poisoning. The heads of the caudate and nuclei appear normal, and there is no significant overall atrophy of the brain. These are findings that tend to exclude Huntington disease while the high signal intensity within the globus pallidus and putamen is atypical for Parkinson disease. Gliomatosis cerebri, an infiltrating astrocytoma of the white matter, is excluded by the fact that the disease process spares the white matter where the tumor occurs. The correct response is Wilson disease.
Wilson’s disease
PKAN eye of the tiger
The basal globus pallidus lesions produce an “eye of the tiger” on MRI, seen with pantothenate kinase deficiency (PKAN). The globus pallidus lesions are from iron deposition. Huntington disease produces caudate atrophy; Niemann-Pick type C disease may have dystonia and rigidity but does not produce isolated globus pallidus lesions. Idiopathic torsion dystonia and Sandifer syndrome have normal MRI
Fahr’s syndrome
Fahr’s syndrome. Idiopathic basal ganglia calcification, also known as Fahr disease, is a rare, genetically dominant, inherited neurological disorder characterized by abnormal deposits of calcium in areas of the brain that control movement.
Carbon monoxide
Hypoxic ischaemic encephalopathy
Discussion:
The correct answer is hypoxic-ischemic injury. There is diffuse symmetric T2 hyperintensity and restricted diffusion involving
the cortex and deep gray matter structures, with diffuse edema. This patient had a cardiac arrest due to respiratory depression
from drug overdose. Meningitis, encephalitis, status epilepticus, and gliomatosis do not produce this pattern of brain injury.
confusion and abnormal movements
Huntingtons
Huntington’s
Discussion:
Huntington disease: Diffuse cerebral atrophy, Atrophy of caudate nucleus.
Hypoxic ischemic injury
Methanol toxicity
Confusion
Wernicke’s
Mesial temporal sclerosis
Headache and diplopia
Tolosa Hunt
MRI the enhancing lesion in right cavernous sinus and meninges present in this case
Tolosa–Hunt syndrome (THS) is a rare disorder characterized by severe and unilateral headaches with orbital pain, along with weakness and paralysis (ophthalmoplegia) of certain eye muscles (extraocular palsies).
Headache and diplopia
Tolosa Hunt
Visual disturbance
Optic neuritis (NMO)
Neuromyelitis Optica: Autoimmune inflammatory disorder involving myelin of neurons of optic nerves and spinal cord, with limited brain parenchymal involvement. 3 segments of T2 abnormality more likely in NMO or acute transverse myelitis than in classic MS.
Revised diagnostic criteria for definite neuromyelitis optica (NMO) require optic neuritis, myelitis, and at least two of three supportive criteria: MRI evidence of a contiguous spinal cord lesion 3 or more segments in length, onset brain MRI nondiagnostic for multiple sclerosis, or NMO-IgG seropositivity. CNS involvement beyond the optic nerves and spinal cord is compatible with NMO
Lymphoma
Diplopia
Ocular myositis or pseudotumor or thyroid
Pilocytic astrocytoma in NF1
NF1 with bilateral optic gliomas
MRI of the brain demonstrates markedly enlarged optic nerves, the left greater than the right, typical of optic nerve gliomas. The coronal plexus study demonstrates an ovoid homogeneous enhancing lesion typical of a nerve sheath tumor. The combination of peripheral nerve sheath tumors and optic nerve gliomas is seen in conjunction with neurofibromatosis type 1 and is not a feature of the other choices. NF type 2 and schwannomatosis are not associated with optic nerve gliomas.
Pineocytoma
pineoblastoma
Neurocytoma (multiple times)
Discussion:
Central neurocytoma is the best diagnosis, based on lesion morphology, location, signal intensity and contrast enhancement pattern. Central neurocytomas are located in the ventricles near the foramen of Monro and characteristically have attachment to the septum pellucidum, as shown in this case. Choroid plexus papillomas and meningiomas enhance intensely, and do not assume this morphology that is so characteristic of central neurocytoma. Subependymomas do not typically enhance. Lymphoma is not typically an intraventricular lesion, but instead infiltrates subependymal tissue and surrounds the ventricles, if involvement is near
the ventricles.
Neurocytoma
subependymoma
Subependymoma
Choroid plexus papilloma
vividly enhancing
usually in children, or younger adults
in adults more common in the 4th ventricle
(2-30 seconds) of uncontrollable laughter, without impairment of consciousness,
Hypothalamic hamartoma
Hypothalamic hamartomas, also known as tuber cinereum hamartomas, are benign non-neoplastic heterotopias in the brain that typically occur in the region of the hypothalamus, arising from the tuber cinereum, a part of the hypothalamus located between the mammillary bodies and the optic chiasm.
Craniopharyngioma
Pituitary macroadenoma
Pituitary microadenoma
- Lymphoma: Discussion:
There is an ovoid homogeneously enhancing mass with adjacent vasogenic edema. A hemorrhage, hemorrhagic infarction or demyelinating lesion would not have this pattern of homogeneous enhancement. A giant aneurysm would not show this degree of edema. This pattern is most frequently seen with lymphoma.
Pituitary apoplexy
Pituitary apoplexy -T1 hyperintense
Rathke cyst
Rathke Cyst
Osmotic demyelination (multiple times)
Osmotic demyelination most frequently affects the central pons, typically sparing the more peripheral fibers, but in some patients may also affect extrapontine sites. Osmotic demyelination is highly associated with electrolyte abnormalities such as hyponatremia that is rapidly corrected. Basilar artery occlusion can affect this region, but frequently would have more extensive abnormality corresponding to the vertebrobasilar arterial supply territory and a less gradual onset. Both osmotic demyelination and basilar artery infarction would have restricted diffusion on MR. Rhombencephalitis is unlikely to be so isolated to the mid pons, but would more likely also involve adjacent cerebellum. Pontine glioma is infiltrative and causes mass effect, enlarging and distorting the pons. Methanol poisoning results in cerebral subcortical white matter abnormality and hemorrhagic infarction of the putamina.
Pontine glioma
Superficial siderosis
Superficial siderosis is a rare condition which results from the deposition of haemosiderin along the leptomeninges, with eventual neurological dysfunction.
On imaging, it is classically characterised on MRI as a rim of low signal coating the surface of the brain or spinal cord, particularly noted with the gradient echo or susceptibility weighted sequences.
Dandy Walker
Dandy Walker
Dandy-Walker malformation (DWM) is the most common posterior fossa malformation, characterised by the triad of:
hypoplasia of the vermis and cephalad rotation of the vermian remnant
cystic dilatation of the fourth ventricle extending posteriorly
enlarged posterior fossa with torcula-lambdoid inversion (torcula lying above the level of the lambdoid due to abnormally high tentorium)
Dandy Walker Malformation
Agenesis of the Corpus callosum
No CC or SP
CC agenesis
Aicardi syndrome
Aicardi syndrome is a rare severe developmental disorder. It results from an X-linked genetic defect that is fatal in males and therefore only manifests in females (except for rare 47-XXY cases).
Chiari I malformation
- Surgical excision
Congenital dermal sinuses can be found anyplace along the neural axis, generally in the midline. In contrast to the very frequently
found dimples and pits over the coccyx, any deep dimple or pit, particularly with hair tuft, should prompt surgical excision. As
the skin lesion is often connected to underlying structures and a dermoid, neuroimaging is mandatory, and surgery should be
done by an experienced pediatric neurosurgeon. Simple excision of the skin component is not appropriate. Excision prior to onset
of infection and neurologic deficits has an excellent prognosis.
cape like sensory sx
Chiari 1 with syringomyelia
Chiari II
Sagittal T1-weighted image shows a Chiari II malformation with deformity of the tectum of the mesencephalon, caudalization of the cerebellar vermis into the cervical spinal canal, and a deformity of the medial aspect of the cerebral hemisphere, with an absent posterior corpus callosum. The cerebral aqueduct is not visualized, and the ventricles do not appear enlarged, suggesting there is aqueductal stenosis and that a functioning shunt should be present as was the case. There is a high degree of association between the cerebral changes of Chiari II malformation and the presence of a lumbar myelomeningocele, thus the lumbar spine should be and was dysraphic. Patients with Chiari II malformations do not have to be and are frequently not mentally retarded. There is no evidence of contusion, subdural hematoma, or other forms of trauma on the section shown.
Pituitary apoplexy:
Discussion:
The study demonstrates increased density within the pituitary fossa extending to the cavernous sinuses bilaterally with an expansive lesion, which is demonstrated on the FLAIR and T1 view areas of both increased and decreased signal. There is an ovoid mass throughout the suprasellar cistern compressing the optic chiasm. It appears as that of a large pituitary mass, likely a pituitary macro adenoma. There is a perimeter of increased T1 weighted signal in the non-contrast view. A compilation of these features would be that of hemorrhagic transformation i.e. pituitary apoplexy of the pituitary tumor mass. A pituitary tumor of this size can be expected to result in bitemporal hemianopia. However, in the absence of hemorrhagic transformation, one would not expect to the tumor’s presence to result in coma as seen with this patient. A colloid cyst would not be expected in this location and generally arises as an intraventricular lesion adjacent to the foramen of Monro in the third ventricle. A metastatic lesion within the sella would be in the differential of a tumor mass; however, again, it would not be the best clinical explanation for the patient’s clinical presentation of sudden coma.
NF1
Discussion:
MRI of the brain demonstrates markedly enlarged optic nerves, the left greater than the right, typical of optic nerve gliomas. The coronal plexus study demonstrates an ovoid homogeneous enhancing lesion typical of a nerve sheath tumor. The combination of peripheral nerve sheath tumors and optic nerve gliomas is seen in conjunction with neurofibromatosis type 1 and is not a feature of the other choices. NF type 2 and schwannomatosis are not associated with optic nerve gliomas.
Trauma
Discussion:
The CT provided demonstrates hematomas within the right frontal region, along with subarachnoid hemorrhage overlying the right hemisphere. The pattern is typical of contusions which arise in the interface between the bone surfaces. In addition, there is an obvious right parietal soft tissue hematoma. This pattern of hemorrhage with contusion is not typical of an aneurysmal rupture, nor would encephalitis present with this pattern of intracranial hemorrhages and subarachnoid hemorrhage. There is evidence of
subdural hemorrhage; however, no epidural hematoma is seen in this view.
Aqueductal stenosis
Aqueductal stenosis (less impressive version)
The patient has markedly enlarged lateral and third ventricles on axial views, with a small (or absent) cerebral aqueduct on sagittal views. These findings are most consistent with aqueductal stenosis.
In colpocephaly there is dilation of the atrium of the lateral ventricles, as in this patient, but not of the temporal horn, present here. In Dandy-Walker syndrome there is partial absence of the vermis of the cerebellum, not present here. The Miller-Dieker syndrome includes lissencephaly, not present here. In this age group normal pressure hydrocephalus is not as frequent as aqueductal stenosis. In addition, a communicating hydrocephalus of this kind would be accompanied by some dilation of the fourth ventricle.
Hydranencephaly
Hydranencephaly or hydrancephaly is a condition in which the brain’s cerebral hemispheres are absent to varying degrees and the remaining cranial cavity is filled with cerebrospinal fluid.Hydranencephaly (or hydrancephaly) is a type of cephalic disorder.
Holoprosencephaly – LEFT – alobar; MIDDLE – semilobar; RIGHT -lobar
Congenital CMV
1.Congenital aquaductal stenosis
Discussion:
The patient has markedly enlarged lateral and third ventricles on axial views, with a small (or absent) cerebral aqueduct on
sagittal views. These findings are most consistent with aqueductal stenosis. In colpocephaly there is dilation of the atrium of the
lateral ventricles, as in this patient, but not of the temporal horn, present here. In Dandy-Walker syndrome there is partial absence
of the vermis of the cerebellum, not present here. The Miller-Dieker syndrome includes lissencephaly, not present here. In this
age group normal pressure hydrocephalus is not as frequent as aqueductal stenosis. In addition, a communicating hydrocephalus
of this kind would be accompanied by some dilation of the fourth ventricle.
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Septo-optic dysplasia
Septo-optic dysplasia (SOD), also known as de Morsier syndrome, is a condition characterised by optic nerve hypoplasia and absence of septum pellucidum and, in two-thirds of patients hypothalamic-pituitary dysfunction. It is best thought of as being part of the holoprosencephaly spectrum (see classification system for midline malformations).
Joubert
Joubert anomaly, also known as vermian aplasia or molar tooth midbrain-hindbrain malformation, is an autosomal recessive disorder where there is a variable degree of cerebellar vermal agenesis.
Patients most commonly present with partial seizures in the second decade of life.
Gray matter heterotopias
The grey matter heterotopias are a relatively common group of conditions characterised by interruption of normal neuronal migration from near the ventricle to the cortex, thus resulting in “normal neurons in abnormal locations” 2. They are a subset of disorders of cortical formation 3-4.
cafe au lait spots and endocrine hyperfunction (such as precocious puberty)
Polyostotic fibrous dysplasia
Discussion:
The correct answer is polyostotic fibrous dysplasia. This finding can be part of the McCune-Albright syndrome, when there are associated multiple cafe au lait spots and endocrine hyperfunction (such as precocious puberty). Despite being classified as one of the neurocutaneous diseases, the McCune-Albright syndrome does not seem to be specifically associated with seizures, though seizures secondary to bone distortion have been reported. In eurofibromatosis type 1, bones develop erosions due to compression by adjacent neurofibromas and schwannomas, but hyperostosis is not seen. Sturge-Weber, multiple myeloma, and osteosarcoma do not produce the type of lesions seen here.
Benign enlargement of the subarachnoid space
Discussion:
The study does demonstrate cerebral hemispheres which are small relative to the internal dimensions of the intracranial cavity as
seen with benign enlargement of the subarachnoid space of infancy, also known as benign external hydrocephalus. Those conditions are generally considered incidental or congenital variants and are not per se abnormal. However, overlying the cerebral hemispheres are subdural fluid collections with increased signal on the FLAIR and T1 weighted views without enhancement. The appearance is typical subacute to chronic subdural hematomas. The calvaria is not thicken or hyperplastic.
Infants with benign enlargement of the subarachnoid space of infancy are believed at higher vulnerability of developing subdural
and epidural hematomas.
1.Extent of vascular calcifications
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Discussion:
The correct answer is extent of vascular calcification. The Spetzler-Martin grading system for AVMs takes into account the size, involvement of eloquent cortex, and the venous drainage pattern (i.e. into deep venous circulation versus into superficial venous sinuses). The number of feeding arteries is also a critical factor, as AVMs with multiple feeding arteries may be less amenable to surgical intervention. Vascular calcifications can be seen on both feeding arteries and dilated draining veins and does not significantly affect the probability of a successful surgical repair.
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Open lip schizencephaly
Discussion:
The images show clefts extending from the extra-axial space to the lateral ventricles bilaterally. These are most characteristic of open-lip schizencephaly. In porencephaly, the cyst is not lined by cortex, as it is here. In hydranencephaly there is little brain tissue around a central cyst. The appearance of encephalomalacia due to trauma is different, with areas of mixed signal intensity in frontal, temporal or occipital regions.
Porencephaly
Porencephaly is a rare congenital disorder that results in cystic degeneration and encephalomalacia and the formation of porencephalic cysts. The term is used variably among radiologists with its broadest definition being a cleft or cystic cavity within the brain 9, and its more narrow definition being a focal cystic area of encephalomalacia that communicates with the ventricular system and/or the subarachnoid space.
Lissencephaly - no sulci - smooth brain
Lissencephaly is a set of rare brain disorders where the whole or parts of the surface of the brain appear smooth.
Vein of galen aneurysm
Discussion:
When Vein of Galen aneurysms present in the neonate, it is usually with congestive heart failure, due to shunting of 25% or more
of cardiac output through the malformation. Vein of Galen malformations presenting later in infancy present with progressive hydrocephalus, with expanding cranium and bulging fontanelle. Similar malformations later in childhood or adolescence may present with Parinaud syndrome and/or mental retardation, and multifocal infarctions due to ischemia from steal phenomena.
Vasculitis - beading
Vertebral artery clot (left vert)
AVM
AVM
AVM
AVM
AVM
Cavernous hemangioma
Cavernous hemangioma is the best choice. The lesion appearance suggests a very limited differential diagnosis, mainly limited to subtypes of cerebral cavernous malformations (aka cavernous hemangioma, cavernoma). Fetures of T1 and T2 hyper intensities with T2 hypo intense rings give the lei on the so-called “popcorn” appearance characteristic of cavernous malformations. None of the other choices would have this appearance
Cavernous hemangioma “popcorn”
Dural AV fistula w/ thrombosis
Developmental venous anomaly (DVA)
Colloid cyst
Colloid cyst
Colloid cysts are classically located at the anterior roof of the third ventricle at the foramen of Monro. They can lead to sudden ventricular obstruction at the foramen of Monro. Patients are typically in their third to fourth decade of life and present with intermittent or persistent headaches due to the increased intracranial pressure from obstruction of CSF outflow. Colloid cysts are treated microsurgically, endoscopically, or with biventricular shunts in nonsurgical candidates. These are surgical emergencies in cases of acute hydrocephalus. Colloid cysts are typically hyperdense on noncontrast CT and typically do not demonstrate any enhancement. While MR characteristics are variable due to the variations in protein, mucin, and water content of the cyst fluid. Calcifications and hemorrhage are rare.
Colloid cyst
Epidermoid cyst
Arachnoid cyst
Transverse myelitis
- Chiari 1 malformation
Discussion:
The correct answer is Chiari 1 malformation. There is cerebellar tonsillar ectopia (approximately 1 cm below the foramen magnum) with an associated cervical syrinx, findings consistent with Chiari 1 malformation. The contents of the syrinx correspond to CSF (i.e. T1 hypointense and T2 hyperintense). The lesion has distinct margins and displaces rather than infilatrates adjacent spinal cord. Astrocytomas are infiltrating tumors. Basilar invagination refers to narrowing of the foramen magnum due to upward migration of the top of the C2 vertebrae. Multiple sclerosis causes demyelinating lesions of the brain and spinal cord and is not associated with tonsillar ectopia. Chordomas are tumors of notochord remnants which most often occur in the clivus and sacrococcygeal regions.
Lipoma
Discussion:
The correct answer is lipoma. The MRI shows an intradural extramedullary mass which is fairly homogenous and is T1
hyperintense and STIR hypointense. The STIR sequence suppresses fat signal, suggesting that this mass is composed of fat. The
other answer choices are lesions which are either not composed of fat or not found in the intradural extramedullary space.
Subacute combined degeneration of the cord
sc abscess
Cord contusion (multiple times)
Discussion:
Cord contusion is the best response because there is gross traumatic injury to the spinal column with disruption of the C4-C5 ligamenta flava, interspinous ligaments, and posterior longitudinal ligament. There is fracture deformity of C5 vertebra consistent with a flexion teardrop fracture and fracture of C6. There is prevertebral soft tissue edema, and the cord has T2 hyperintense signal at the C5 and C6 level consistent with traumatic cord contusion with some intramedullary hemorrhagic component. Neuromyelitis optica, ependymoma, abscess, and sarcoid myelitis are not the best choices because the extensive vertebral column injuries are not consistent with the typical presentation of any of these entities.
- Neurosarcoidosis
Discussion:
Sarcoidosis is an idiopathic systemic disease that can involve any part of the central nervous system. Spinal sarcoidosis can
produce a broad spectrum of imaging findings ranging from intramedullary, intradural extramedullary, and extradural to vertebral body lesions. Intramedullary sarcoidosis is most commonly seen in the cervical cord, whereas extramedullary intradural lesions
typically involve the cauda equina.
Cavernous angioma
Cavernous angioma/cavernoma
Dural spinal AV fistula
Dural AV fistula
- Epidural lipomatosis: Discussion:
The study depicts a marked increase of fat tissue within the epidural space most marked from L4 to the sacral region, which
results in spinal stenosis as seen with a small triangular-shaped thecal sac at L5- S1. The signal characteristics are those of
subcutaneous fat tissue and not CSF. Congenital spinal stenosis as a result of short pedicles is not seen on this study. The patient
does have mild disc disease at L4-5 and L5-S1. They are inadequate to produce spinal stenosis and result in spinal claudication,
as seen with this patient. The conus is not well demonstrated, but is not low- lying; nor are there any imaging features to suggest
tethering of the cord.
Ependymoma (contrast on right)
Astrocytoma - contrast on right
Spinal AVM
MR images demonstrate dilatation of the cord around a central cystic cavity, consistent with syringohydromyelia. Note also on the sagittal images that the inferior portion of the cerebellum has herniated down into the upper cervical canal, diagnostic of a Chiari malformation. Hydromyelia is commonly seen in association with both Chiari type I and Chiari type II malformation
Meningioma
Meningioma - enhanced on right
Arachnoid cyst - T1 and T2
Thoracic arachnoid cyst
Discussion:
The figure demonstrates widening of the CSF space posterior to the spinal cord in the mid thoracic region, resulting in anterior displacement and compression of the cord at that level best seen on the T2 weighted view with somewhat ovoid appearance. This is also well demonstrated as a region of isointense signal to CSF on the T1 weighted views and shows no enhancement. The most common etiology of this appearance is that of a thoracic arachnoid cyst. An epidermoid cyst is an additional, although less likely, etiology and not one of the choices. A lipoma in this location would have increased T1 weighted signal similar to subcutaneous fat tissue not seen here. Similarly, a meningioma would not show the very bright T2 weighted signal and the hypodense signal on T1 weighted view. Myelomalacia within the cord may develop, although is not depicted on this study. The signal of characteristics are not hemorrhage as would be seen in an intrathecal hematoma.
Chance Fracture
Discussion:
60
This study demonstrates a linear fracture defect which includes all three vertebral columns extending horizontally through the vertebral body, the pedicles, and through the facet joints. This lower thoracic fracture is termed a chance fracture, which is a fracture occurring most commonly in the lower thoracic or upper lumbar regions from T11 to L2. A chance fracture is a result of hyperflexion of the back, most commonly seen in motor vehicle accidents, in belted patients, resulting in a wedge shaped compression fracture which includes posterior elements of the vertebra. Half of these patients also have an abdominal injury. This should be considered an unstable fracture until proven otherwise. Spondylolisthesis without spondylolysis is incorrect as there is no subluxation demonstrated. The fracture margins are sharply demarcated and not the pattern of chronic fractures.
Lipoma
lipoma
lipoma with lumbar stenosis
cervical spine lipoma
T2/T1+Contrast – neurofibroma – schwannomas look super similar
neurofibromas
Neurofibromas
hemangioma - T1 and T2 hyperintense
- Epidural Abscess
Discussion:
Sagittal T1-weighted images demonstrate a loculated fluid collection in the posterior epidural space, extending for several levels in the mid-thoracic spine. The collection causes significant compression and anterior displacement of the spinal cord. Note on both sagittal and axial images that the subarachnoid space is also compressed, placing this in the epidural, not intradural space (excluding meningioma). This is a typical appearance of a loculated, encapsulated epidural abscess. A 10-day-old hematoma
should be hyperintense on T1-weighted images. Epidural metastases and myeloma are of soft tissue signal, generally nearly isointense to neural tissue and usually are anteriorly located, extending posteriorly from vertebral body lesions.
Vertebral mets
Multiple myeloma (multiple times)
Discussion:
The figures demonstrate a diffuse heterogeneous appearance of the vertebrae, “salt and pepper pattern.” There is also a larger focal enhancing lesion extending into the pedicle of L2 along with compression fractures. This pattern of diffuse osseus invasion can be seen due to hematologic diseases and is most typical of multiple myeloma. Thalassemia is associated with marrow reconversion with the repopulating of yellow marrow by hematopoietic cells, but that would not be expected to show this salt and pepper pattern or a focal lesion as in L2, nor would metastatic carcinoma. There are pathologic compression fractures and some kyphotic posturing, but these would not be the best answers.
Spinal infection
Discitis
Osteomyelitis, discitis and epidural abscess
Epidural abscess, - loculated and enhancing
Discitis
Synovial cyst
Synovial cyst
Calcified synovial cyst
Discussion:
The parasagittal and axial views demonstrate an ovoid cystic nodule with decreased signal within the right lateral recess at the junction of the right facet joint, which somewhat left laterally displaces the spinal cord and results in severe right lateral recessed stenosis. This lesion shows marked decreased signal, as seen on the parasagittal study, typical of calcium, a most common calcified cystic nodule at the junction of the facet joint would be a calcified synovial cyst. While free disc fragments can be seen in this location, a calcified cystic disc nodule would be rare. A lateral disc herniation is not seen. A cystic meningioma in this location would similarly be a rare and not the most likely finding. A cystic nodule has no features suggestive of a bony
osteophyte or spur.
Synovial cyst
Drop Mets
Drop met or nerve sheath tumor (shwannoma / neurofibromatoma
Drop mets
Osteomyelitis
Spinal sarcoid
AIDP - enhancing roots / cauda
Erosion of odontoid process (RA most common preceeding cause)
Discussion: 1. ra
The mass lesion with isointense signal on T1- and bright T2-weighted signal posterior to the dens is most frequently due to
pannus. The inflammatory pannus involving the dens is often seen in association with rheumatoid arthritis.
Syringohydromyelia
Klippel-Feil Syndrome
Klippel-Feil syndrome (KFS) is a complex heterogeneous entity that results in cervical vertebral fusion. Two or more non-segmented cervical vertebrae are usually sufficient for diagnosis.
Tethered cord (conus at sacrum)
Demyelinating polyneuropathy
Discussion:
The following studies demonstrate homogenous enhancement of the cauda equina with suggestion of mild thickening of the nerve roots. This pattern can be seen in conjunction with Guillain–Barré syndrome, chronic inflammatory demyelinating polyneuritis, leptomeningeal carcinomatosis, granulomatous disease, or lymphomatosis. There is no evidence of a tethered cord or low-lying conus. B12 deficiency results in lesions within the posterior column and the spinal cord not seen on this study. Ruptured dermoid can result in lipid particles distributed throughout the neuraxis which are not seen on this study and leptomeningeal tumor seeding would be inconsistent with a reversible course of leg weakness.
Double bonus – tethered cord and lipoma (conus down all the way to sacrum!)
The conus terminated at the L5-S1 level constituting a tethered cord syndrome. There is also a homogeneous mass with brightly increased T1- and T2-weighted signal. This signal pattern is typical of a lipoma. A tumor or Tarlov cyst would have decreased T1 signal. No abnormal signal as seen in a spinal cord infarction is seen.
Diastematomyelia with tethered cord
The MRI demonstrates a diastematomyelia with an associated bony and cartilaginous or fibrous septation at L2-3, along with a low lying tethered cord adherent at the L4 level. This is a form of congenital dysraphism. The symptoms of this condition are primarily due to the stretching of the spinal cord, which in frequently present with this condition and corrected by detethering and frequently with the removal of the septations
Myelomeningocele
L4/5 Disc space - symptomatic root is L5
Anterior subluxation of C5 anterior to C6. Naked Facet sign.
Spondylolysis
is defined as a defect or stress fracture in the pars interarticularis of the vertebral arch. The vast majority of cases occur in the lower lumbar vertebrae (L5), but spondylolysismay also occur in the cervical vertebrae.
Spondylolysis
Spondylolisthesis
Spondylolisthesis is a condition in which one bone in your back (vertebra) slides forward over the bone below it.
Chance fracture
Odontoid fracture
Odontoid type II fracture
The correct answer is Type 2 odontoid fracture with spinal immobilization and neurosurgical/orthopedic evaluation. Type 1 odontoid fractures involve the tip of the dens and are stable fractures. Type 2 odontoid fractures occur at the base of the dens and are considered unstable. Type 3 odontoid fractures involve the base of the dens as well as the facets lateral to the odontoid process, and can be either stable or unstable. Spinal immobilization and neurosurgical/orthopedic evaluation is essential for type 2 odontoid fractures given their instability. In this case, the fracture results in slight anterior displacement of the odontoid fracture (seen on the sagittal image). The greater the displacement, the greater the risk of non-union. This patient underwent surgical placement of an odontoid screw for fixation of the fracture.
Type II odontoid fracture
- Dorsiflexion weakness
Discussion:
Lumbar and sacral nerve roots exit below their corresponding vertebral body, but do so laterally and superiorly through the neural foramina. Therefore, at the L4-L5 disc interspace, the L4 nerve root exits above and lateral to the herniated disc. Neuroimaging here demonstrates a right posterolateral disc extrusion that likely impinges upon the descending right L5 nerve root, which would result in right extensor hallucis longus weakness. In contrast, a far right lateral disc herniation could theoretically result in an L4 nerve root compression, but this in not depicted in this MRI. The other answer choices correspond to physical exam findings associated with other nerve roots (i.e., adductor longus weakness [L3], decreased patellar reflex [L4], decreased ankle jerk reflex [S1], saddle anesthesia [S3-5
Meningocele: dilatation of the terminal sac of the spinal cord.
Spinal cord arteriovenous malformations (AVMs) are relatively rare lesions, accounting for fewer than 5% of space-occupying lesions of the spine. The image shows a large feeder vessel from C4 to approximately T1, the main nidus of the lesion. There are blood products visible in the cord below the main lesion and holocord edema above and below the lesion
HIV and IV heroin abuse
Spinal cord neurofibroma
The patient presented here has multiple neurofibromas of spinal nerves, and a plexiform neurofibroma infiltrating the nerves forming the left brachial plexus. Although multiple spinal tumors can be seen in both NF-1 (pathology is neurofibroma) and in NF-2 (pathology is schwannoma), plexiform neurofibromas are not seen in NF-2. The remaining diagnoses are not consistent with the images. Metastatic disease may infiltrate through a neuroforaminen but is unlikely to enlarge it. Ependynomas are intramedullary tumors. Nerve sheath diverticulum are hypointense on T1-weighted studies and do not enhance
Back pain and ambulatory dysfunction
Syrinx: T2 weighted thoracic spine reveals syrinx from T6- T9 with moderate degenerative central canal stensis, most pronounced at T6/7. A syrinx is a fluid filled cavity that develops in the spinal cord. If they develop late in life usually due to tumors.
(old) Gait instability, leg weakness, urine. 6/12. HTN, heavy smoker. Dx?
Meningioma. Homogenous enhancement and dural based location
- Leg weakness, urinary incontinence, belt sensation. Distal weakness, decreased ankle jerk, preserved knee.
Transvere myelitis. “conus syndrome” numbness tends to be localized perianally, knee jerks preserved but ankles lossed (due to sacral segments involved) retention and atonic anal spincter cause overflow urinary incontinence and faecal incontinence. MRI showes hyerintense lesion L1-2
Optic neuritis + this – dx?
Devics disease
45, HIV +ve, 1/12 progressive weakness. 3 yrs HIV, irregular treatment, IVDU. N CN, UL 4/5, LL 4-/5 tone increased, reflexes brisk, sensation decreased, VP to C5. incoordination present.
HIV myelopathy. T2 hyperintensity in the C spine, most marked at C5. symmetric non enhancing signal multiple contiguous slices may result from extensive vacuolation. Called vacuolar myleopathy as there is swelling and vacuolation of the myelin sheath on microscopy. Associated with AIDS dementia.
Acute left sided weakness. Plain CTB
Dense vessel sign
What can you see?
Bilateral xanthogranulomatous formation in choriod plexi which is an incidental finding. 1.5-7%
WHAT IS THIS
DNET (dysembryoplastic neuroepithelial tumor) is the best response. The images demonstrate the typical intracortical location with “soap-bubble” appearance at the cortical margin, FLAIR hyperintensity at the margins, and no contrast enhancement is present. The lesion is located in the right frontal operculum. Abscess, cerebritis, and ganglioglioma would typically have
abnormal contrast enhancement, not a feature in the current case. Infarction would be very unlikely to leave the rim of intact cortex that in this case maintains normal signal intensity
RITE 2017 (picture may not be the same)
Hypertensive encephalopathy, a cause of reversible posterior leukoencephalopathy syndrome (RPLS), is a rapidly evolving condition that develops in patients with malignant hypertension. If not promptly recognized and aggressively treated it leads to progressive neurological deterioration and death. Renal failure and eclampsia are contributory causes. Similar changes are also seen in toxicity due to immunosuppressive agents. MRI and CT show edema located in the occipital and parietal lobes and other posterior regions. These findings are seen in 85% of patients studied within 72 hours after onset of symptoms. The relative lack of sympathetic innervation in vertebrobasilar vasculature may predispose this region to the development of the cerebral edema
Posterior leukoencephalopathy syndrome (PRES), also called reversible posterior leukoencephalopathy (RPLE) is characterized by headache, confusion, seizures and visual loss. It may occur due to a number of causes, including malignant hypertension, eclampsia and numerous medications. On magnetic resonance imaging there is cortical and/or juxtacortical edema, generally more in the parietal occipital and posterior frontal regions and bilaterally. Multiple sclerosis and progressive multifocal leukoencephalopathy (PML) are predominately white matter diseases but would be unlikely to present in such a bilaterally symmetric pattern. Numerous small metastases along the juxtacortical margin could produce a similar pattern of edema but would be unlikely and there are no adjacent tumors nodules on the post contrast view.
For headache. Dx?
Cavernous angioma. Intravascular malformation that develop from the vascular bed. May be asymptomatic r can present with headache, seizures, or small parenchymal hemorrhages. Can be found in any part of the brain, although frontal and temporal lobes are the most common sites of occurrence – about 85% of the cavernous angiomaas are supratentorial. Pop corn appearance
40, diplopia and vertigo
Basilar artery aneurysm. CT head shows a basilar artery aneurysm with intrluminal calcified material. Confirmed with CTA showing proportion filling with contrast.
The most likely diagnosis is ruptured aneurysm. The high density of the recent bleeding outlines the subarachnoid space around the brain. Its shape rules out the other types of hemorrhage mentioned as options. There is hydrocephalus, but it is not idiopathic; rather, it is caused by the subarachnoid hemorrhage. The air with pneumocephalus would have a much lower density than any of the structures seen on the image
Routine scan for migraine
Arachnoid cyst - hypodensity, left temporal pole. Treated with decompressive procedure if clearly symptomatic
- Sinusitis, 3,4,6th Nerve palsy.
Left cavernous and left superior opthalmic veins enlarged – cavernous sinus thrombosis. A large focal non- enhancing lesion centrally within the superior opthalmic vein compatible with thrombus is seen
Headache: plain CTB
Haemorrhage: left thalamus lesion likely acute haemorrhage ICH site predilection are basal ganglia, lobar, thalamus, pons, cerebellum and other brainstem
Type of poisoning
Carbon monoxide poisoning: bilateral globus pallidus lesions are typically seen in hypoxia and with conditions that cause tissue hypoxia such as carbon monoxide or cyanide poisoning.
The T1 noncontrast image demonstrates an isointense ovoid mass in the right superior cerebellum with a perimeter of decreased signal. This lesion demonstrates multiple flow voids on the postcontrast view within the central and perimeter of the mass, There is decreased signal on the T2-weighted view with adjacent margin of increased signal typical of hemorrhage with edema and multiple contrast-enhancing vessels on the CT angiogram including a large draining vein along with a central nidus. The appearance is typical of an arteriovenous malformation.
- Low grade fever. Dx?
Abscess. Increased DWI with decreased ADC – characteristic of ischamic or abscess. No clear vascular terriroty.
40, headaches, vomiting,
Glioblastoma multiforme – ring enhancing mass, heterogenous enhancemnet. Aggressive primary brain tumors
HEADACHE
Meningioma. Homogenous contrast enhancement, well defined contours, dural tails
- Headache. CT and MRI shown.
(choices given meningioma, lymphoma, haemorrhage, oligodendroglioma, neuroccysticercosis)
Of options given most likely oligodendroglioma.
Changed mental state. Post contrast T1. What is it?
Esthesioblastoma- A neuroblastoma (neural crest derived tumor) that arisees from the olfactory neural cells. The site of origin as the olfactory area in this case is clearly suggested in the coronal image. Esthesioblastomas are mostly unilateral mases and rarely calcify
Which kind of stroke would cause this picture
Artery of heubner: Recurrent artery of Heubner arises at the level of the anterior communicating artery, most commonly from the A1 or A2 segment of the anterior cerebral artery. Supplies th ehead of the caudate, anterior limb of the internal capsule, anterior globus pallidus, and anterior putamen, the anterior thalamus, and parts of the uncinate fasciculus, olfactory region, and hypothalamus. Hemiparesis with predominanace of face and arm
Anterior choroidal artery
Discussion:
The combination of the patient’s physical exam and neuroimaging findings is consistent with a right anterior choroidal artery infarction. The anterior choroidal artery is a branch of the internal carotid artery and supplies the posterior limb of the internal capsule and the lateral thalamus. The paramedian thalamic artery is a branch of the posterior cerebral artery and supplies the medial thalamus. The ophthalmic artery is a branch of the internal carotid artery and supplies the retina.
80, gait instability memory loss 2 years, incontinence.
NPH. Enlarged ventricles, moderate atrophy, bilateral white matter periventricular disease.
Leptomeningeal carcinomatosis
Discussion:
The images shown demonstrate enhancement with layering along the cerebellar folia and an enhancing nodule within the dependent segment of the fourth ventricle. This pattern of leptomeningeal enhancement is typically seen with carcinomas, or bacterial meningitis. Systemic sclerosis is associated with layering of hemosiderin from prior hemorrhages, not seen in this study. Bacterial meningitis can produce a similar pattern of enhancement; however, one would not expect 2 months of progressive ataxia or a nodule within the fourth ventricle, as seen in this study. Hemangioblastomas occur frequently in the posterior fossa; however, one would not expect layering of tumor along the folia. Cerebellitis is an inflammatory condition generally seen in younger people, as compared to this individual, and can produce enhancement along the folia but would not be associated with a fourth ventricular nodule.
- Gait instability, big head, developmental delay. Dx?
Dandy – Walker Malformation. Rare congenital malformation of the cerebellum and fourth ventricle. Agenesis or hypoplasia of the cerebellar vermis and cystic enlargement of the fourth ventricle and dilatataion of the posterior fossa. Generally – developmental delay, enlarged head, signs/ symptoms of hydrocephalus
The dilated third ventricle projects superiorly between bodies of the lateral ventricles. A corpus callosum is not seen, therefore this is agenesis of the corpus callosum
CTs demonstrate extensive bilateral edema with intracranial hemorrhage. Coronal suture is widely spread, and a skull fracture is visible. In a 2-month-old, the most likely etiology is nonaccidental trauma. The most common presentations of nonaccidental trauma (NAT) are decreased responsiveness, respiratory difficulties, and seizures
- Obstructive hydrocephalus
Discussion:
The correct answer is obstructive hydrocephalus. The sagittal image shows a pineal mass that is compressing the tectum of the
midbrain and narrowing the cerebral aqueduct. The axial image shows transependymal flow into the brain parenchyma above the
level of the obstruction.
1yo seizure – RITE 2017 (picture may have been different)
Schizencephaly is a disorder of neuronal migration, with CSF filled cleft that is lines by gray matter. Extends from ventricular surface to periphery. May be closed (schizencephaly type I) or open (Type II). Associated with a number of other abnormalitites including gray matter heterotopia and polymicrogyria, arachnoid cysts, microcephaly, septum pellucidum absent, septo-optic dysplasia.
The images show clefts extending from the extra-axial space to the lateral ventricles bilaterally. These are most characteristic of open-lip schizencephaly. In porencephaly, the cyst is not lined by cortex, as it is here. In hydranencephaly there is little brain tissue around a central cyst. The appearance of encephalomalacia due to trauma is different, with areas of mixed signal intensity in frontal, temporal or occipital regions.
- Heterotopia
Discussion:
These images show multiple small periventricular nodules, isointense to the gray matter, along the lateral ventricular wall consistent with heterotopia likely due to a migration error.
- Septo-optic dysplasia
Discussion:
This case demonstrates : Absent septum pellucidum, small optic nerves/chiasm compatible with Septooptic Dysplasia. 75-90%
have brain abnormalities; 45% have pituitary insufficiency. Child with short stature, endocrine dysfunction, Normal or color
blindness, visual loss, nystagmus, strabismus mental retardation, spasticity, microcephaly, anosmia.
6 yo – diplopia and falls. 6th CN, R face weakness
Pontine glioma – expansive mass around to pons, given the patint age, highly suggestigve.
- Focal seizures. Biopsy: small, oval, well differentiated cells with positive staining for glial fibrillary acidic protein (GFAP). Dx?
Fibrillary astrocytoma.
Astrocytomas are brain tumors derived from astrocytes. They’re divided into 2 classes: astrocytes with restricted infiltration (ie pliocytic astrocytoma, subependymal giant cell astrocytoma, and pleimorphic xanthoastrocytoma) 2 astrocytomas with diffuse zones of infilatration – such as low grade astrocytoma, anaplastic astrocytoma and glioblastoma.
Astrocytoma with diffuse infiltration can be located at any site – peak 30-40 yrs, 25% of all astrocytomas in adults.
Histo – 4 different variants of low grade astrocytomas – protoplasmic, gemistocytic, fibrillary, mixed
Protoplasmic- abundant cytoplasm
Gemistocytic – large globoid astrocytes with eosinophilic cytoplasm
Fibrillary – small, oval, well diferrentiated fibrillary background with GFAP
- R brain tumor. CN III palsy
Descending transtentorial right herniation. Can cause various sx including dilatation of the pupil and abnormal extraocular movements (secondary to compression of ipsilateral CN III), contralateral hemiparesis (2 compression of the ipsilateral corticospinal tracts). Other complications include unilateral or bilateral occipital lobe infarction (2 to compression of the posterior cerebral artery).
Herniation syndromes are caused by intracranial mass effect. The image shows a transtentorial herniation of the left temporal lobe and uncus. Subfalcine herniation is not the best choice because the image does not show the level of the falx. Tonsillar herniation occurs at the level of the foramen magnum when cerebellar tonsillar tissue is forced out by mass effect. The foramen magnum is not visible in the image supplied. Extracranial herniation occurs in the setting of a skull defect (either traumatic or therapeutic) that allows brain to pass through the defect. No skull defect is present in the supplied image. Ascending herniation occurs when a mass in the posterior fossa forces cerebellar tissue to move upward and cross the tentorial incisura, not seen in the current image
Persistent headache. Dx?
Intracranial hypotension. Spontaneous intracranial hypotension is an important cause of new perisitent daily headaches but is not well recognized it is typically affected by postural headahces due to a leak of the CSF. MRI shows bilateral subdural collections with discrete enhancement – likely secondarily to meningeal venous encorgement),
- Glial alpha synuclein inclusions.
The clinical history and gross brain features are typical of multiple system atrophy (MSA). This disorder is characterized by neuronal loss, gliosis, and glial cytoplasmic inclusions (containing alpha-synuclein). Neuritic plaques are found in Alzheimer Disease, globose neurofibrillary tangles are seen in PSP, Lewy bodies in Parkinson Disease, and tufted astrocytes are also a feature of PSP.
Blood vessel involved?
Epidural haematomas. Produce lentiform shape. Form from arterial blood (middle meningeal artery bleed with overlying temporal bone fracture is commonest)
Acute headache, seizure, Pregnant. CT – parasagittal hemorrhage. MRV shown. Aetiology and treatment?
Sagittal sinus thrombosis. Treatment is anti-coagulation (usually heparin)
Boxer. Crossed signs – r cerebellar, R face, L extremities. (face and arm resolve)
Vertebral artery dissection causing transient Wallenberg Syndrome symptoms and with a subsequent completed right cerebellar peduncle infarction. Angiogram shows vertebral artery narrowing
FTD
Discussion:
This relatively young patient shows a progressive syndrome of language impairment with a gait and behavioral abnormality, most consistent with frontotemporal lobar degeneration (FTLD). The PET image shows a progressive metabolic decline particularly in the orbitofrontal region.
A normal spectrum is shown. The tallest peak is N-Acetyl-Aspartate (NAA) and represents neuronal activity (normal). To the left of the NAA peak are the (normal) creatinine and (normal, smaller) choline peaks
Metastatic disease to orbit
Axial CTs show a large mass lesion filling the right orbit, compressing and deforming the posterior margin of the globe. The inferior cut through the maxillary sinus shows that the lateral wall of the maxilla is destroyed and is associated with the soft tissue mass. Metastatic disease commonly involves bone and adjacent soft tissue, as in this case. Facial trauma does not produce a disappearance of bone but fractures it. Fibrous dysplasia expands bone but does not destroy it. Hemangioma may involve bone and soft tissue, but is not a destructive process. In the orbit, capillary hemangiomas are commonly found in the cutaneous tissues and periorbita but do not extend retroglobar and do not destroy bone. Cavernous hemangiomas are discrete masses that may be found intraorbital or extraorbital but do not usually cross these margins.
