Computed Tomography (CT):distinguishes tissue density (no density = black)machine moves around a still patientnon-invasive, fast, painlessavailable in all ERsCT scanner rotates a narrow x-ray beam around the head. The quantity of x-ray absorbed in small volumes (voxels [volume elements]) of brain, measuring 0.5 mm x 1.5 mm, is computed. Amount of x-ray absorbed in any slice of the head can be thus determined; absorption is proportional to density of the tissue. Black/white pictures of head slices are displayed; black represents low-density and white high-density structures.A series of 10 or 20 scans, each reconstructing a slice of brain, is required for a complete study.Magnetic Resonance Imaging - MRIMagnetic field + radio wavesUsed to see:edemahemorrhagetumorstakes 40-60 min, like motionless, noisy, not always availablespatial distribution of elements with an odd number of protons (such as hydrogen) within slices of brain can be determined by their reaction to an external radio frequency signalPositron Emission Tomography (PET)NSC 4366 1st Edition Lecture 3Outline of Last Lecture I. Introduction to skull anatomyOutline of Current Lecture I. Neurologic Imaginga. x-rayb. MRIc. CTd. PETe. Cerebral angiographyCurrent LectureSkull x-ray:• a simple method to image calciumand its distribution in and aroundthe brain when more precisemethods (CT) are unavailable.Computed Tomography (CT):• distinguishes tissue density (nodensity = black)• machine moves around a still patient• non-invasive, fast, painless• available in all ERsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.• CT scanner rotates a narrow x-ray beam around the head. The quantity of x-ray absorbed in small volumes (voxels [volume elements]) of brain, measuring 0.5 mm x 1.5 mm, is computed. Amount of x-ray absorbed in any slice of the head can be thus determined; absorption is proportional to density of the tissue. Black/white pictures of head slices are displayed; black represents low-density and white high-density structures.• A series of 10 or 20 scans, eachreconstructing a slice of brain, isrequired for a complete study.Magnetic Resonance Imaging - MRI• Magnetic field + radio waves• Used to see:• edema• hemorrhage• tumors• takes 40-60 min, like motionless, noisy, not always available• •spatial distribution of elements with an odd number of protons (such as hydrogen) within slices of brain can be determined by their reaction to an external radio frequencysignal Positron Emission Tomography