Board Review 3 – Case 5

Posted on March 31, 2020March 30, 2020 by Brent Weinberg, MD

Board Review 3 – Case 5

Neuroradiology 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 shows multiple hemorrhagic and hyperdense masses on a CT. They are predominantly supratentorial, have some edema, and are numerous.

On MRI, the regions have areas of susceptibility (dark T2 signal on GRE), surrounding edema, and enhance avidly.

The diagnosis is: metastatic disease

Intracranial metastases are extremely common and should be considered any time there are multiple masses (although 50% may be solitary). They can have hemorrhage and almost always enhance on post-contrast imaging. The most common locations are supratentorial and at the gray white junction because of the high vascularity there.

Metastases are treated with surgery or radiation. If there is oligometastatic disease (less than 10-20 lesions), stereotactic radiosurgery may be performed. Numerous lesions or leptomeningeal disease can require whole brain radiotherapy.

Full Playlist on Youtube

Board Review 3 – Case 4

Posted on March 29, 2020March 25, 2020 by Brent Weinberg, MD

Board Review 3 – Case 4

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

This case shows an expansile extra-axial mass along the left frontal and parietal calvarium. On CT, it is hyperdense to the adjacent brain and it is causing mass effect and edema in the surrounding brain.On MRI, it is relatively T2 homogenous, appears to be arising outside the brain, and enhances homogenously and avidly.

The diagnosis is: meningioma

Aggressive extra-axial lesions, particularly those causing cortical destruction, have a differential including metastasis, meningioma, lymphoma, and myeloma. You may not be able to differentiate these by imaging.

Meningiomas are the most common brain tumors and most common extra-axial masses. They range in aggressiveness from WHO grade 1 (typical), grade 2 (atypical), and grade 3 (anaplastic), which is determined primarily on histologic features and not imaging criteria. Grade 1 tumors are treated with resection while grades 2 and 3 receive resection followed by radiation therapy.

Full Playlist on Youtube

Board Review 3 – Case 3

Posted on March 27, 2020March 25, 2020 by Brent Weinberg, MD

Board Review 3 – Case 3

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

This case shows a nodular mass along the right frontal calvarium in a patient with pain. It is T2 hyperintense, T1 hypointense, and enhances avidly.

The diagnosis is: skull metastasis

Any mass in the calvarium that has associated osseous destruction is concerning. Benign masses often contain fat (are T1 hyperintense and suppress on T2 fat-saturated imaging) and rarely destroy the cortex. Pain, as was experienced by the patient in this case, is also a concerning feature.

Any patient with a concerning calvarial mass but no history of malignancy should probably be evaluated for metastatic disease. While the evaluation may vary by institution, it will most commonly consist of a whole body PET/CT or CT of the chest, abdomen, and pelvis.

Full Playlist on Youtube

Board Review 3 – Case 2

Posted on March 25, 2020 by Brent Weinberg, MD

Board Review 3 – Case 2

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

This case shows a nodular multifocal mass along the walls of the ventricles. It is relatively low intensity on T2, hyperintense on DWI, and enhances avidly with a nodular solid pattern.

The diagnosis is: CNS lymphoma

Primary CNS lymphoma is a B-cell malignancy with relatively low incidence but overall poor outcomes. It is more common in immunocompromised or HIV patients. The most common locations are in periventricular white matter, the basal ganglia, and the corpus callosum. Solid nodular enhancement, T2 hypointensity, and low ADC values are characteristic. In fact, lower ADC values are associated with a poorer prognosis.

HIV and immunocompromised patients are more likely to have variable enhancement patterns, such as rim enhancement with central necrosis.

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Board Review 3 – Full lecture

Posted on March 23, 2020 by Brent Weinberg, MD

Board Review 3 – Full lecture

This lecture is a board review lecture geared towards preparation for the radiology resident ABR core exam, although similar material is used for the ABR certifying exam general and neuroradiology sections.

The format of this lecture is case-based. Each case consists of a series of images followed by 1 or 2 questions. The first question is usually to name the diagnosis, while the second is a multiple choice question to test deeper understanding of the specific condition. Try to get the diagnosis before you see the second questions.

The first 10 cases cover brain tumors and the remaining 9 cover general neuroradiology. The final case will be a high speed multiple choice review.

Neuroradiology board review lecture 3 introduction

Neuroradiology board review 3 case 1

Neuroradiology board review 3 case 2

Neuroradiology board review 3 case 3

Neuroradiology board review 3 case 4

Neuroradiology board review 3 case 5

Neuroradiology board review 3 case 6

Neuroradiology board review 3 case 7

Neuroradiology board review 3 case 8

Neuroradiology board review 3 case 9

Neuroradiology board review 3 case 10

Neuroradiology board review 3 case 11

Neuroradiology board review 3 case 12

Neuroradiology board review 3 case 13

Neuroradiology board review 3 case 14

Board Review 3 – Case 1

Posted on March 23, 2020 by Brent Weinberg, MD

Board Review 3 – Case 1

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

This case shows a minimally enhancing mass along the anterior part of the septum pellucidum. This patient also has hydrocephalus which may be contributing to the symptoms.

The diagnosis is: subependymoma

Masses in the ventricles and along the septum pellucidum have a broad differential diagnosis, but in this case subependymoma is the best fit because it is a relatively indolent appearing, minimally enhancing mass.

The other possibilities include:

ependymoma – usually has more avid enhancement
central neurocytoma – also usually has more enhancement
subependymal giant cell tumor (SEGT) – possible, but more likely in a patient with tuberous sclerosis
choroid plexus tumor – more commonly enhances avidly
hemangioblastoma – often will have flow voids
metastatic disease – also more avid enhancement

If you see a minimally enhancing ependymal/subependymal tumor, think about subependymoma.

Full Playlist on Youtube

Noncontrast MRI (magnetic resonance imaging) cervical spine search pattern

Posted on March 22, 2020 by Brent Weinberg, MD

Noncontrast MRI cervical spine search pattern

Magnetic resonance imaging (MRI) of the cervical spine is a very commonly encountered test which can be performed for a variety of indications, including degenerative disease, trauma, demyelinating disease, and metastatic disease. Most of these cases will be done without contrast, as most of the information is there on a non-contrast exam.

This video will walk you through a step-by-step approach to evaluating an MRI of the cervical spine. The optimal approach is to use select sequences to evaluate each part of the study in the following order:

Alignment
Vertebral bodies
Marrow signal
Intervertebral discs
Spinal cord/canal
Soft tissues
Individual levels

Each sequence in the study has strengths at looking at one or more of these things. As we walk through, we’ll take a look at how to use each one.

The level of this lecture is appropriate for medical students, junior residents, and trainees in other specialties who have an interest in neuroradiology or may see patients with spine diseases.

See this and other videos on our Youtube channel.

Neuroradiology physics review – 2 – Magnetic Resonance Imaging

Posted on January 18, 2020 by Brent Weinberg, MD

Neuroradiology physics review – 2 – Magnetic Resonance Imaging

It’s important for the neuroradiologist to have a basic grasp of physics, particularly in the ways that it may affect image quality. In this video, Dr. Michael Hoch goes through a series of 13 MRI cases on physics. Each case is followed by one or more multiple choice questions about that physics principle.

There are a number of ways that physics principles affect MR images, causing various types of suboptimal images, such as:

metallic artifacts – areas of signal loss around susceptibility created by metal
fat suppression artifacts – areas where fat is incompletely saturated, particularly at the edge of images or adjacent to metal
aliasing – where one part of the image is incorrectly mapped to another area due to improper field of view
staircase – motion between slices leading to step offs in reconstructed images
chemical shift artifact – when a substance such as fat has a different resonance frequency and maps elsewhere into an image
zipper/spike artifact – when an external source of frequency noise is mapped into the image domain

Other key principles discussed include:

how artifacts may help you make a diagnosis
differences in how artifacts may appear on different types of images
how to change sequences to mitigate artifact

The level of this lecture is appropriate for radiology residents, radiology fellows, and trainees in other specialties who would like to review radiology physics. This may be particularly useful when preparing for the American Board of Radiology (ABR) core and certifying exams.

Check out this video and additional content on https://www.learnneuroradiology.com

Youtube Playlist

Neuroradiology physics review – 1 – Computed Tomography

Posted on October 2, 2019January 18, 2020 by Michael Hoch, MD

Neuroradiology physics review – 1 – Computed Tomography

It’s important for the neuroradiologist to have a basic grasp of physics, particularly in the ways that it may affect image quality. In this video, Dr. Michael Hoch goes through a series of 12 CT cases on physics. Each case is followed by multiple choice questions about that physics principle.

There are a number of ways that physics principles affect images, causing various types of suboptimal images, such as:

partial volume averaging – when an object only takes up part of a voxel and the resulting output
patient motion – when patient moves during imaging, degrading image quality and causing image blurring
streak artifact – when high density material adversely affects CT reconstruction, causing lines across an image
ring artifact – when a detector fails and causes rings through the image
contrast staining – when breakdown of the blood brain barrier allows leakage of contrast into the brain

Other key principles discussed include:

pitch
computed tomography dose index (CTDI)
dose length product (DLP)
pre- and post-patient collimation
image filtration

Youtube Playlist

Intracranial infections – 5 – Other

Posted on September 24, 2019September 11, 2019 by Brent Weinberg, MD

Intracranial infections – 5 – Other

There are a few other infectious considerations which have special imaging appearances and which you should keep in mind. This includes neurocysticercosis and Creutzfeldt-Jakob disease (CJD).

This lecture is the final in a series of 5 about imaging intracranial infection and covers diffuse brain infections. The series of videos will cover:
1) General considerations
2) Diffuse infections
3) Focal infection
4) Immunocompromised patients
5) Other considerations

Neurocysticercosis is a brain infection caused by the pork tapeworm. It is a common infection in Latin America and is a common acquired cause of seizure. While the imaging appearance varies with stage, it most commonly has a cystic lesion in the brain parenchyma with peripheral enhancement and surrounding edema. Racemose cysticercosis can involve the CSF spaces, including the ventricles or sylvian fissures. Chronic cysticercosis commonly has punctate peripheral calcification, which can be a clue in patients with this infection.

Creutzfeldt-Jakob disease (CJD) is a prion disease which is commonly thought of as infection because of its association with contaminated beef (bovine spongiform encephalopathy), but most cases (approximately 85%) are spontaneous, with the remainder familial/inherited. Image findings include bilateral symmetric abnormalities of the basal ganglia and thalamus, including signs such as the pulvinar sign or hockey stick (describing thalamic involvement). Cortical linear involvement, or cortical ribboning, is also common.

In summary, there are a variety of infections in the brain ranging from meningitis/encephalitis through focal infections such as abscess and PML. Awareness of these infections is necessary to make an appropriate diagnosis in these patients.

The level of this lecture is appropriate for radiology residents, radiology fellows, and trainees in other specialties who have an interest in neuroradiology or may see patients with CNS infections.

Other videos on the intracranial infection playlist are found here.