NeuroRad cases

Question 1

• What are the 3 anatomical divisions of neuroradiology?
• What are the 2 main imaging modalities?

Answer 1

• 3 main anatomical divisions
  
  1. Brain
  2. Spine
  3. Head and neck
• 2 main imaging modalities
  
  • Computed Tomography (CT)
  • Magnetic Resonance Imaging (MRI)

Question 2

What are common CNS pathologies of the brain?

Answer 2

1. Stroke
2. Multiple sclerosis
3. Hypertension
4. Aneurysm
5. Tumor
6. Trauma

Question 3

What are common CNS patholiges of the spine?

Answer 3

1. Facial trauma
2. Infection
3. Squamous cell carcinoma
4. Atheroscleroticvascular dz
5. Other malignant disease

Question 4

What are common pathologies of the head/neck?

Answer 4

1. Degenerative disease
2. Infection
3. Metastatic disease
4. Trauma

Question 5

When is contrast used in CT?

Answer 5

• CTs of the head and neck soft tissues looking for infection or malignancy
• CT angiograms of the head and neck
• **CT venograms **of the head and neck
• A few others

Question 6

• When is IV gadolinium used for MRI?
• What is contrast usually not used for?
• MRA head usually done (with/without) contrast
• MRA neck and MRV best when done (with/without) contrast

Answer 6

• Indications for IV gadolinium contrast in MR imaging
  
  • Infection
  • Primary tumors or metastatic disease
  • Demyelinating disease (MS)
  • A few others
• Not usually done for stroke evaluation
• MRA head usually done without contrast
• MRA neck and MRV best when done with contrast

Question 7

ACR Appropriateness for minor head trauma:

• What is the most appropriate scan?

Answer 7

• CT w/o contrast

Question 8

Addtional factors to consider (CT vs. MRI):

• Cost:
• Ionizing Radiation:
• Time to acquire:
• Patient Cooperation:
• Contrast Material:
• Ferronizing material (pacemakers, anuerysm clips, bullets):

Answer 8

Question 9

What is on the radiology differential diagnosis for acute intracranial hemorrhage?

Answer 9

• Trauma
• Vasular malformation
• Aneurysm
• HTN
• Underlying neoplasm
• Cerebral Amyloid Angiopathy
• Venous Thrombosis
• Anticoagulation
• Drug abuse
• Hemorrhage conversion of infarct

Question 10

What is the best image to find the source of a bleed for an acute intracranial hemorrhage?

Answer 10

CT angiography of the head

Question 11

What are the findings of this Head CTA?

Answer 11

• Large lobulated saccular aneurysm arising from an azygos anterior cerebral artery
• Increased size of the right paramedian frontal hematoma which dissects into the subarachnoid and subdural spaces

Question 12

Acute Intracranial Hemorrhage: Take home points

• Acute hemorrhage is _________ on CT
• Chronic hemorrhage is _________ on CT
• Locations include: ….
• Two most common causes of subarachnoid hemorrhage are ….
• To look for an aneurysm on CTA, ______ is needed
  
  • What about for an MRA?

Answer 12

• Acute hemorrhage is hyperdense (bright) on CT
• Chronic hemorrhage is hypodense (dark) on CT
• Locations include: subarachnoid, subdural, epidural, parenchymal, and intraventricular
  
  • Knowing the location of hemorrhage can help you work through a differential diagnosis
• Two most common causes of subarachnoid hemorrhage are trauma and ruptured aneurysm
• To look for an aneurysm on CTA, contrast is needed.
  
  • No contrast necessary for MRA

Question 13

What is the clinical differential diagnosis for acute infarcts?

Answer 13

• Cerebrovascular accident
• Transient ischemic attack
• Seizure
• Encephalopathy

Question 14

Acute Infarct: Take Home Points

• Should you use a CT?
• What determines your level of suspicion?
• What is the most important role of a CT scan?
• What is the best image?
• What is the key to finding an acute infarct?

Answer 14

• May not see acute infarct on CT
• Let clinical context determine level of suspicion
  
  • If high, get an MRI.
• The most important role of CT in the acute stroke workup is to look for hemorrhage
• Best MRI sequence to look for acute ischemic infarct is DWI (diffusion weighted imaging).
• Knowing functional anatomy is key

Question 15

What is the diagnosis of this CT?

Answer 15

• Severe fracture dislocation injury at C7 - T1 with jumped facets
• Numerous spine fractures (most of which are not pictured)

Question 16

What can be used to examine the spinal cord, spinal ligaments, and possible epidural hematoma?

Answer 16

MRI

Question 17

What is diagnosis from this MRI?

Answer 17

• Cord contusion w/ edema at C7 and T1
• Severe cord deformity from the dislocation
• No cord hemorrhage
• Some epidural hematoma
• Numerous ligaments damaged

Question 18

Spinal Trauma: Take Home Points

• What is the best exam for screening?
• What is the sensitivity for CT scans?
• What is a MR scan used for?

Answer 18

• CT is the initial screening exam for trauma patients not cleared clinically
• Sensitivity for cervical spine injury 90-100% with CT
  
  • 50-75% with plain films
• MR is used to evaluate for soft tissue abnormalities such as disc, ligament, nerve, or cord injuries

Question 19

• What is seen in this CT scan?
• What is the concern?

Answer 19

• Tubular foreign body (ballpoint pen) penetrating the left naris, left nasal cavity, right posterior ethmoids, right sphenoid sinus, right clinoid, and medial right temporal lobe, terminating in the atrium of the lateral ventricle
• Concern for optic nerve injury and vascular injury (internal carotid artery)