Diagnostic Imaging Flashcards
X-Ray (plain film)
Standard study
Multiple views - min 2, 90 degrees from each other
Shows bones well
Poor soft tissue viewing
Joint above and below a freacture should always be viewed on initial films
X-Ray Checklist
Adequate exposure Correct side of the body Correct patient Proper viewing area Minimum 2 images 90 degrees from each other ABC'S
ABC’S (of what you see)
Alignment
Bone
Cartilage
Soft Tissue
Computer Tomography (CT Scan)
Best study for bone anatomy especially in complex areas
Soft tissue is seen, but not as well as MRI
Often used in comminuted fractures and preop planning
Offers a 3D reconstruction
Slices are taken in mm axial incremints
More expensive than XR
Much more radiation
Magnetic Resonance (MR)
Best study for soft tissue, IV discs, ligaments, and tendons Highly sensitive for osteonecrosis Two types of images Used in preop planning No radiation
Two types of MR images
T1 and T2
T1 images
Weighted for fat
Good for nomal anatomy
Fat shows as white
Fluid shows as black
T2
Weighted for water
Good for pathology
Fat shows as black
Fluid shows as white
Compact bone on MRI
Appears as dark on both T1 and T2
Low signal
Bone Scan
Radioactive isotope injected into the blood, Technetium-99 (Tc99m)
Imaging of whole body shows areas of increased uptake
Good for identifying tumor, fractures, infections, and heterotopic bone activity - can’t tell difference
Arthrography
Contrast injected into a joint followed by XR or MR
Evaluates capsular integrity
Myelography
Contrast injected into epidural space
Evaluates disc herniation and cord tumors
Usually followed by XR and/or CT scan
Discography
Contrast injected into nucleus pulposus to evaluate disc degeneration
Usually followed by XR and/or CT
Not common procedure anymore
Ultrasound
Good for r/o DVT
Commonly used to measure size of cyst or tumors
Used at times for finding foreign objects
Evaluating rotator cuff pathology
