MRI in Neuroradiology

Β 
Β 
Applied Practical Neuroradiology
Chapter Outline
Introduction
Focus on Acute Inpatient Neuroimaging
Treat the patient not the image
Choose wisely - Will it change your management
Techniques in Neuroimaging (Chapter 1 Neuroradiology - Requisites 3rd Ed)
Basic Concepts in Neuroimaging
Steps to review Neuroimaging
First Pass: Spaces in Brain, Midline shift
Second Pass: Side to side comparison
Third Pass: Zoom in to abnormality (one view is no view)
Fourth: Choose Wisely - What to order next
Doppler Ultrasound - Flow dynamics
CT Hounsfield Unit and windowing
Perfusion Neuroimaging
Diffusion Neuroimaging
MR Sequences and implication
Functional Neuroimaging
SPECT and PET Neuroimaging
Indication for contrast enhanced study
Patterns of Contrast Enhancement and implications
Etiology Specific Neuroimaging
Ischemic Stroke
Hemorrhagic Stroke
Brain Tumors
Global Hypoxia-Ischemia
Brain Death
Pattern recognition - Neuroradiology Signs
Future Neuroradiology
NeuroRadiology OrderSet
Best Online Resources
Further Reading
Introduction
Focus on Acute Inpatient Neuroimaging
Treat the patient not the image
Choose wisely - Will it change your management
Techniques in Neuroimaging
  • Plain Films
  • Digital Radiography
  • Computed Tomography/CT
  • CT Perfusion
  • Magnetic Resonance Imaging/MRI
  • Magnetic Resonance Angiography/MRA
  • Diffusion-Weighted Imaging/DWI
  • Perfusion Scanning
  • Functional Magnetic Resonance Imaging/FMRI
  • Contrasts Agents
  • Magnetic Resonance Spectrometry/MRS
  • Magnetization Transfer Imaging/MT
  • Angiography
  • Contrasts for Angiography
  • Myelography
  • Ultrasound
Applications of Ultrasound in Infants or In Utero:
  • Detect regions of intraparenchymal or intraventricular hemorrhage.
  • Congenital anomalies as Dandy-Walker cysts, agenesis of the corpus callosum, lipomas, and holoprosencephaly can also be detected.
  • Extra-axial collections, hydrocephalus, and cystic encephalomalacia may also be seen.
  • Detect anencephaly, hydrocephalus, and neural tube defects in the spinal canal.
Applications of Ultrasound in Adults:
  • Doppler studies are the best sonographic indicator of stenoses of the internal carotid artery that are greater than 70%.
  • Most intraocular masses can be readily evaluated with ocular sonography.
  • Doppler ultrasound to evaluate the direction of flow in the superior ophthalmic vein, to suggest the diagnosis of cavernous-carotid fistulas
  • Transcranial Doppler studies are used to evaluate velocities of intracranial vessels.
  • Nuclear Medicine
    • Branch of radiology dealing with instillation of radioactive substances into the body and then detecting the emissions of the agents with crystal scintillation devices (gamma cameras).
    • Most commonly used nuclear agent in planar brain scanning is Technetium (Gamma ray emitter of 140keV; T Β½ of 6 hours).
    • Another tracer used is Indium-111 Diethyl Pentaacetic acid (Gamma ray emitter of 173keV; T Β½ of 2.8 days) used in suspected communicating hydrocephalus, normal pressure hydrocephalus and sinonasal CSF leaks.
    • On a normal uptake scan, uptake is only in vascular (usually venous) structure.
    • Positron Emission Tomography/PET -
      • Deals with positron-emitting isotopes of chemical agents produced in a cyclotron(type of a particle accelerator).
      • Positron is a positively charged antimatter equivalent of an electron that is emitted by the isotope that combines with negatively charged electrons to produce gamma radiation. This radiation can be detected by scintillation cameras on the opposite side of the patient.
      • Typical agents used for PET are Fluorine-18-Labeled Deoxyglucose (FDG), Carbon-11-Labeled Deoxyglucose and methionine.
      • Used for glucose utilization or blood flow through the brain.
      • Clinical application of PET include tumor detection, differentiation of tumor from radiation necrosis, Parkinson disease (decreased activity in Putamen)
Intracranial indications for PET studies:
  • Differentiation of tumor from radiation necrosis
  • Parkinson disease (Decreased activity in putamen)
  • Alzheimer disease (temporal lobe and hippocampal activity markedly decreased; putamen activity normal)
  • Effectiveness of drug treatment in neuropsychiatric disorders
  • Detect presence and extent of initial recurrent, or residual, disease in patients of head and neck cancers before and after treatment.
Drawbacks and Limitations of PET studies:
  • Relatively poor resolution
  • Mostly need for a cyclotron
  • High Cost
  • Decreased availability in community
  • Single-Photon Emission Computed Tomography/SPECT -
    • Use iodinated radiotracers (iodine-123-labeled iodo-amphetamine) or technetium-99m agents as cerebral perfusion and extraction agents.
    • When compared to PET, relatively stable, cheaper in cost as they it does not require on-site cyclotron.
    • Study uses: stroke, epilepsy and dementia.
Fig 1
notion image
Modalities
Table 1: Comparison of Different Neuroradiology Modalities
Table 2: CT Perfusion
Table 3: MR Sequences
A Living Pocketbook of Neurology
A Living Pocketbook of Neurology
notion image

πŸ§‘β€πŸŽ“ Why Contribute ?

🎟️ Contribution Application
Applied, Concise, Practical, Up-to-date, Mobile-friendly, peer-reviewed & Open-Access Pocketbook of Neurology and related clinical specialties
Unleash the Digital Healer in You! >> 🌐 https://junaidkalia.com <<
Unleash the Digital Healer in You! >> 🌐 https://junaidkalia.com <<
Learn Digital Health, AI-in-Healthcare, ValueBased Care & More!
🎯 Follow Junaid Kalia MD [Editor-in-Chief]
"If anyone saved a life, it would be as if he saved the life of all mankind"
"If anyone saved a life, it would be as if he saved the life of all mankind"
An AINeuroCare Academy Project - Coaching Clinicians in Digital Healthcare
πŸ’‘ Learn! πŸŽ₯ YouTube πŸ’Œ Newsletter πŸŽ“Academy πŸ“ Blog
πŸ‘¨β€βš•οΈ Connect! πŸ‘₯ Linkedin πŸ‘‹ Facebook πŸ•ŠοΈ Twitter πŸ“Έ Instagram

Disclaimer: For Education purposes only. You must NOT rely on the information on this website as an alternative to medical advice from your healthcare provider

CC BY-NC-ND - Attribution-NonCommercial-NoDerivs - AINeuroCare PLLC ©️