Neuroradiology Natasha Wehrli, MS4 University of Pennsylvania School of Medicine

Q: What is radiology?  Answer (from Wikipedia):  Answer (from Wikipedia): Radiology is the branch of medical science dealing with the medical use of radiation devices and other forms of energy for the purpose of obtaining visual information as part of medical imaging. Interventional radiology is the performance of medical procedures with the help of medical imaging.   My answer: the coolest field of medicine ever!

What is a neuroradiologist?   A neuroradiologist is a radiologist who specializes in the use of x-rays and other scanning devices for the diagnosis and treatment of diseases of the nervous system.   A neuroradiologist must be concerned with the clinical imaging, therapy, and basic science of the central and peripheral nervous system, including but not limited to the brain, spine, head and neck.

Goals/Objectives  Review basic anatomic landmarks in the brain  Learn the three different orientations neuroradiologists use to view images of the brain  Be able to distinguish between a CT scan, T1-weighted MR image, and a T2- weighted MR image of the brain

Orientation

Sagittal Plane

Coronal Plane

Axial (Transverse) Plane

What is a CT (or CAT) scan?  CT stands for “computed tomography” - this is a complex machine that uses x-rays to create three- dimensional images of the body

What is bright/dark on CT?  The more dense the tissue, the brighter it looks on CT  Any calcified structure (like the skull) appears bright  New hemorrhage in the brain is also bright  Water (or CSF) looks dark on CT

What is MR?  MR stands for “magnetic resonance” - this is a tool that uses magnetic fields created by a giant magnet to produce three-dimensional images of the human body

The two most common types of MR images are…  T1-weighted MR images- useful to look at normal anatomy of the brain  T2-weight MR images - useful to look at abnormal processes (or pathology) in the brain

What is bright/dark on T1?  Fat is bright  White matter (inner part of brain) is brighter than gray matter (cortex or outer part of the brain)  Water (CSF) is dark

What is bright/dark on T2?  Water is bright  Blood is bright  White matter is darker than gray matter

Other Studies - Angiogram  Some neurologists just want to look at blood vessels in the brain  They can inject a contrast agent and then use x-rays to see the blood flowing inside the artery

Interventional Radiology  Interventional radiologists use x- rays and other imaging tools in the operating room to perform minimally invasive surgery

Neuroradiology is a rapidly advancing field of medicine…  Scientists are creating stronger and stronger magnets to create clearer MR images of the brain!

Neuroradiology is a rapidly advancing field of medicine…  You can also use MR to show areas of blood flow in different regions in the brain - this is called functional MRI  What part of the brain is abnormal in these images? What does this patient have?

Neuroradiology  At the end of today, you should be able to identify the 3 different orientations of the brain as well as a few important structures in the brain  You should also attempt to distinguish CT, T1- weighted MR and T2-weighted MR images Consider a career in neuroradiology! It’s a very rewarding, high-tech specialty with a lot of fun problem-solving. Neuroradiologists also play an important role in diagnosing diseases and helping patients get the most appropriate medical care.

Thanks! References/Resources