CT and MRI

Computed Tomography 1972 __________________ X-ray tube in a tube Rows of _________ opposite x-ray tube Produces ___________________

1 st and 2 nd Generation 1 st generation –_________ –Transmits beam then ________ –Long scan times 2 nd generation –_________ –Transmits a fan beam then _________ –Faster scanning

3 rd and 4 th Generation 3 rd generation –_____________ –More detectors 4 th generation –Detectors _____________ –Continuous rotating x- ray tube

Helical/Spiral scanning ______________technology Tube rotation ____________ Pt movement continuous ______________of data Faster scanning

Hounsfield Units CT Numbers Can determine material based on the __________(linear attenuation coefficient) __________ = 0 Cortical bone = ________= -1000

Multi slice Obtaining multiple slices ____________ Much faster scanning 4, 16, 32, 64 slice And More

Contrast IV – _____________ same as X-ray __________– visualizes GI track ______– quicker visualization of Lower GI

MRI st Installed MRI discovered. Uses primarily –___________ –________________ Good anatomical detail

Magnet Types Resistive ____________ ________________

MRI (Sort of) _______________ Some ___________ in the magnet –Magnetic moment Radiofrequency (RF) –______________ Atoms ___________ Computer recon image

T1 and T2 Weighted MRI visual contrast T1 – ______________ T2 – ______________ Unless it’s blood

MRI IV contrast Not like X-ray ___________ –Metallic based ________________than X-ray –Until recently

Safety _________________________ Carefully screen pt __________________