Fast 10: Neuroradiology high speed case review part 6 – Cases 51-60

In this 6th video, we present 10 more neuroradiology high speed review cases so you can review them quickly before your exams. If you want to see more information about these cases, you can find longer versions on the channel under the Board review playlist

Cases included in this set:
Neurocysticercosis
Sarcoidosis
Subdural hematoma
Limbic encephalitis
Arteriovenous malformation (AVM)
Traumatic shear injury/Diffuse axonal injury (DAI)
Frontal sinus osteomyelitis (Pott’s puffy tumor)
Carotid artery dissection
Tuberculosis lymphadenopathy (Scrofula)
Cauda equina syndrome imaging

Be sure to check back in for the remainder of the high speed cases.

Fast 10: Neuroradiology high speed case review part 5 – Cases 41-50

In this 5th video, we present 10 more neuroradiology high speed review cases so you can review them quickly before your exams. If you want to see more information about these cases, you can find longer versions on the channel under the Board review playlist

Cases included in this set:
Subependymoma
CNS lymphoma
Metastatic disease to calvarium
Meningioma
Metastatic melanoma
Hypothalamic hamartoma
Pituitary adenoma (with hemorrhage/apoplexy)
Pilocytic astrocytoma
Cerebellopontine angle meningioma
Glioblastoma

Be sure to check back in for the remainder of the high speed cases.

Fast 10: Neuroradiology high speed case review part 4 – Cases 31-40

In this fourth video, we present 10 more neuroradiology high speed review cases so you can review them quickly before your exams. If you want to see more information about these cases, you can find longer versions on the channel under the Board review playlist

Cases included in this set:
Renal cell carcinoma
Tuberculosis discitis osteomyelitis
Osteosarcoma of the spine
Ischemia with penumbra (tissue at risk)
Traumatic spine epidural hematoma
Thoracic spine meningioma
Benign perimesencephalic subarachnoid hemorrhage
Chiari malformation
Traumatic vertebral artery injury
Temporal lobe anatomy – fusiform gyrus

Be sure to check back in for the remainder of the high speed cases.

Fast 10: Neuroradiology high speed case review part 3 – Cases 21-30

In this third video, we present some 10 more neuroradiology high speed review cases so you can review them quickly before your exams. If you want to see more information about these cases, you can find longer versions on the channel under the Board review playlist

Cases included in this set:
Vestibular schwannoma
Surfer’s ear (external auditory canal exostosis)
Dural sinus thrombosis
Idiopathic basal ganglia calcification (Fahr disease)
Subclavian steal
Hypertensive hemorrhage
Craniopharyngioma
Ganglioglioma
Synovial cyst
Spinal lymphoma

Be sure to check back in for the remainder of the high speed cases.

Fast 10: Neuroradiology high speed case review part 2 – Cases 11-20

In this second video, we present some 10 more neuroradiology high speed review cases so you can review them quickly before your exams. If you want to see more information about these cases, you can find longer versions on the channel under the Board review playlist

Cases included in this set:
Colloid cyst
Sturge-Weber syndrome
Juvenile nasal angiofibroma (JNA)
Esthesioneuroblastoma
Traumatic ossicular dissociation/dislocation
Cavernous malformation (cavernoma)
Cerebellopontine angle ependymoma
Spine schwannoma
Osmotic demyelination/central pontine myelinolysis
Thyroid ophthalmopathy

Be sure to check back in for the remainder of the high speed cases.

Fast 10: Neuroradiology high speed case review – Cases 1-10

In this video, we present some high speed review cases so you can review them quickly before your exams. This video has the first 10 review cases. We’ll spend about 1 minute on each case so you can learn as quickly as possible. If you want to see more information about these cases, you can find longer versions on the channel under the Board review playlist

Cases included in this set:
Huntington’s disease
Progressive supranuclear palsy
Multisystem atrophy
Creutzfeld-Jakob disease
Parkinson’s disease
Posterior reversible encephalopathy
Leptomeningeal metastases
Subdural hematoma
Pyogenic abscess
Artery of Percheron infarct

Be sure to check back in for the remainder of the high speed cases.

Neuroradiology Board Review – Brain Tumors – Case 20 – Summary

Neuroradiology brain tumor board review. This lecture is geared towards the ABR core exam for residents, but it would be useful for review for the ABR certifying exam or certificate of added qualification (CAQ) exam for neuroradiology.

This video has both the final case of the series and a quick review summary!

Case 20

In this case, you are starting with an immunocompromised patient with HIV. Initial CT images show a hyperdense mass in the left basal ganglia with a lot of surrounding edema. This is helpful, because a few things are known for being hyperdense on CT.

MRI images confirm a mass in the basal ganglia. It is somewhat T2 hypointense with well-defined margins and surrounding edema. On postcontrast images, it has peripheral enhancement but central non-enhancement compatible with necrosis.

The differential diagnosis for a solitary enhancing parenchymal mass is different in an immunocompromised patient (or someone on immune suppressing agents. In an immune normal patient, the top diagnoses are

  • metastatic disease
  • high grade glioma
  • lymphoma

On the other hand in an immunocompromised patient the order of these diagnoses shifts to include:

  • lymphoma
  • infection
  • metastatic disease
  • high grade glioma

As you can see, lymphoma and infection jump to the top in an immunocompromised patient.

The diagnosis is: CNS lymphoma

CNS lymphoma can occur when associated with systemic lymphoma or primarily in the CNS, as in this case. This is most commonly a diffuse large B-cell lymphoma. It is more common in immune compromised patients. It often occurs in the basal ganglia and periventricular white matter and can often be multifocal. Lymphoma is one of the rare diseases which is T2 hypointense, so you should think about it if you see a T2 hypointense mass.

In immunocompetent patients, lymphoma most commonly has solid enhancement. However, in immunocompromised patients it is much more likely to show central necrosis, as in this case. Also, in an immunocompromised patient, it can be hard to differentiate lymphoma from infection, particularly toxoplasmosis. The two most common ways to try to differentiate this are to start a trial of toxoplasmosis therapy for a few weeks and see if the lesions improve and to perform a thallium-201 chloride nuclear medicine scan. Lymphoma has thallium uptake, while toxoplasmosis does not.

Summary

In this board review lecture, you’ve seen a lot of different tumors and how they manifest in different situations. In many cases, you can’t make a definitive diagnosis but you should always be able to come up with a reasonable differential diagnosis. It’s also helpful to know some of the basics about treatment and prognostic factors.

There are two key strategies that I hope can help you get a few additional points, the approach to CP angle masses and the approach to cortical tumors.

Cerebellopontine angle masses

As we’ve seen in some of the other cases, cerebellopontine angle masses can be solid or cystic. Solid masses that involve the IAC and expand it are likely schwannomas, while others outside the IAC are likely meningiomas. Arachnoid cysts and epidermoids are the most common cystic masses which are differentiated by DWI (which is bright in ependymomas.

Cortical tumors

Several of the cases in this series dealt with cortical temporal tumors. Ill-defined masses that are larger are more likely to be low grade gliomas (oligodendrogliomas and astrocytomas). Completely non-enhancing bubbly masses favor DNET. A little nodular enhancement favors ganglioglioma, while pleomorphic xanthoastrocytoma (PXA) can be more avidly enhancing and irregular.

Neuroradiology Board Review – Brain Tumors – Case 19

Neuroradiology brain tumor board review. This lecture is geared towards the ABR core exam for residents, but it would be useful for review for the ABR certifying exam or certificate of added qualification (CAQ) exam for neuroradiology.

More description and the answer (spoiler!) are seen below the video.

This case of a patient with diplopia (double vision) starts with a CT through the orbits. You can see there is a well-defined mass at the right orbital apex.

On MRI, you can see the lesion again is well-defined with well defined margins and is hyperintense on T2. On T1, the lesion is isointense to muscle on pre-contrast and then demonstrates heterogeneous enhancement on postcontrast. It looks like the lesion is enhancing more on the coronal image compared to the axial image.

The diagnosis is: orbital venous vascular malformation

Orbital venous vascular malformations are sometimes referred to as hemangiomas, although this term is falling out of favor because it is not neoplastic (unlike the neoplastic infantile and neonatal orbital hemangiomas). These are relatively benign lesions that can cause visual problems secondary to mass effect, but it’s relatively uncommon for them to enlarge.

One characteristic finding of orbital venous malformations is progressive enhancement on delayed images. On early images, it might be enhancing a little bit but if you have more delayed images, you might see more enhancement. If you don’t have more than one plane of contrast, you can bring them back and image them again 15-30 minutes later and it should fill in.

The primary differential considerations for orbital masses are sarcoidosis, idiopathic or IgG4 related orbital disease, metastatic disease, and lymphoma. When it is this well defined and has the characteristic delayed enhancement, the diagnosis is relatively certain.

Neuroradiology Board Review – Brain Tumors – Case 18

Neuroradiology brain tumor board review. This lecture is geared towards the ABR core exam for residents, but it would be useful for review for the ABR certifying exam or certificate of added qualification (CAQ) exam for neuroradiology.

More description and the answer (spoiler!) are seen below the video.

This case starts with 2 axial images from a CT through the posterior fossa followed by MRI images through the same region. There is a heterogeneous lesion to the left of the midline along the left foramen of Lushka. On postcontrast images, it is pretty avidly enhancing. The enhancing margins are pretty well defined and it looks like it is wholly in the ventricle.

The diagnosis is: ependymoma

Ependymomas are enhancing intraventricular tumors arising from the ependymal lining. They are commonly enhancing and conform to the ventricles and the ventricular outflow tract, which results in their description of “toothpaste” like lesions. In adults, they most commonly occur in the 4th ventricle although in pediatric patients they can occur elsewhere.

When in the posterior fossa, your main differential is choroid plexus papilloma/tumor. If you can’t tell that it’s an intraventricular lesion it can be harder because the differential diagnosis also include metastatic disease and possibly medulloblastoma. If you see a lesion that looks similar but doesn’t enhance very much, think about it’s sister lesion subependymoma.

Neuroradiology Board Review – Brain Tumors – Case 17

Neuroradiology brain tumor board review. This lecture is geared towards the ABR core exam for residents, but it would be useful for review for the ABR certifying exam or certificate of added qualification (CAQ) exam for neuroradiology.

More description and the answer (spoiler!) are seen below the video.

In this case, we have an MRI showing a FLAIR and T2 hyperintense mass in the left insula with relatively ill-defined margins. On SWI, there are some areas of susceptibility that probably represent calcification, although blood products could look similar. Postcontrast images demonstrate little or no contrast enhancement.

1:33 The diagnosis is: oligodendroglioma

Oligodendrogliomas are gliomas which are now defined by the characteristic genetic features of IDH mutation and 1p19q codeletion (loss of portions of both chromosomes 1 and 19). They can be WHO grade 2 (as in this case) or grade 3 (anaplastic oligodendroglioma). Theoretically, these lesions never degrade into WHO grade 4 lesions although the grade 3 lesions can be quite aggressive. In general, oligodendrogliomas have a better prognosis than their sister gliomas, astrocytomas. They respond better to radiation and have better overall survival.

Oligodendrogliomas are treated with a combination of resection and chemoradiotherapy.

The susceptibility seen within the tumor on this case represents areas of calcification. Oligodendrogliomas are one of the main considerations if you see an expansile tumor with calcification.