Spom Imaging
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
834
On Slideshare
834
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
44
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Imaging Techniques
    • Utilize Ionizing Don’t Utilize Radiation Ionizing Radiation
    • Plain Films MR
    • Fluoroscopy US
    • CT
    • Nuclear Medicine
    • Mammography
  • 2. X-Rays
    • High energy photons
    • Similar to visible light
    • But … have a higher energy and a shorter wavelength
  • 3. Plain Films
    • X-ray tube shoots high energy electrons at a target (Tungsten)
    • When the electrons go around the nucleus of the Tungsten atom, the electrons lose energy
    • This occurs by 2 processes: Bremmstrahlung and K shell Knockout
    • Change in the energy of the electron results in radiation and x-ray formation
  • 4. Plain Films
    • Finally, x-rays are collected on:
    • Photosensitive film (permanent)
    • Digital Imaging Plate (permanent)
    • Fluoroscope (temporary)
  • 5. X-Rays
    • Can’t see the x-rays, only the images
    • Image seen is that part of the patient that blocks the x-ray beam.
    • The denser the material, the more difficult it is for the beam to penetrate the anatomic area
  • 6. X-ray Exposure
    • Not all x-rays that enter the body leave it!
    • Absorbed x-rays can damage DNA, affecting future cells, causing mutations or cell death
    • Keep in mind, x-rays can be diagnostic or therapeutic
  • 7. X-ray Exposure continued
    • X-ray exposure is cumulative
    • It is important to assess the Risk/Benefit ratio
    • 1. Does the patient really need the study?
    • 2. Can the study be done with other non-x-ray diagnostic studies?
    • 3. Can non-vital areas be shielded?
  • 8.  
  • 9. Densities
    • Air - Lungs, Bowel gas
    • Fat - Omentum
    • Soft tissue - Muscle, Solid Organs
    • Bone - Skeleton, Calcifications
    • Metal - Hardware, Contrast
  • 10.  
  • 11.  
  • 12.  
  • 13. Inspiration Expiration
  • 14. Chest X-Ray Features
    • Symmetry - unilateral vs. bilateral
    • Location - upper, middle, lower, peripheral, central, anterior, posterior
    • Size
    • Number - Single, Multiple
    • Borders - Smooth, Irregular
    • Density - Solid, Air, or Fluid filled, or Combination
  • 15.  
  • 16.  
  • 17.  
  • 18. Fluoroscopy
    • Live images obtained while a procedure or maneuver is being performed.
    • X-ray beam patient
    • X-ray strikes
    • coupled Fluorescent Plate
    • Image Intensifier
    • coupled TV Camera
    Image
  • 19.  
  • 20.  
  • 21. Ultrasound
    • High frequency sound waves sent into tissue and the reflected echoes create an image.
    • Real time images-demonstrate motion –ex. fetal heart beat
    • Doppler images-demonstrate speed and direction of flow in a vessel – ex. carotid artery
  • 22. Ultrasound Continued
    • Thorax - Heart-wall thickness, motion, valves
    • Abdomen - Liver, spleen, pancreas, kidneys, masses, solid, cystic, stones
    • Pelvis - Female-Ovaries, uterus, fetus,
    • Male-Prostate, masses
    • Vasculature - Aorta-Aneurysms
    • Peripheral vessels-DVT
  • 23. Ultrasound Continued
    • Densities:
    • Black - anechoic - low density - fluid
    • Gray - echogenic - medium density - soft tissue
    • White - hyperechoic - high density - calcium
  • 24.  
  • 25.  
  • 26.  
  • 27.  
  • 28.  
  • 29.  
  • 30. CT
    • In the gantry, there’s a series of small x-ray sensors which rotate. They take multiple x-ray pictures from various angles. Computers interpret the data, compiling the many images obtained. The images appear as cross-sectional slices obtained at many levels.
  • 31. CT continued
    • Advantages
    • Almost all anatomic areas visible
    • Use with or without oral/IV contrast
    • Quick
    • Can differentiate different densities-air/fluid/soft tissue/bone
  • 32. CT continued
    • Disadvantages
    • Ionizing Radiation
    • Cost
    • Not available at all institutions
    • May be hampered by metal/star artifact
  • 33. CT continued
    • Densities- Hounsfield Units
    • Low Attenuation - black (air)
    • High Attenuation - white (bone)
  • 34.  
  • 35.  
  • 36.  
  • 37.  
  • 38. CT/MR
    • Key Features to Assess
    • Asymmetry
    • Masses or mass effect
    • Midline shift
    • Fluid collections
  • 39. CT/MR continued
    • MR Advantages
    • Multiplanar images (axial, coronal, sagittal, oblique)
    • Greater gray/white differentiation
    • More detailed anatomy
    • Better visualization of subacute and chronic bleeds and spinal cord compression (trauma or mets)
    • CT Advantages
    • Availability
    • Speed
    • Cost
    • Can detect calcium and acute bleeds more easily
    • Accommodates patient monitoring equipment
  • 40. MR
    • MR utilizes a magnetic field and radiofrequency antennas (coils) to obtain an image
    • The magnetic field causes all of the protons in the patient’s body to line up
    • Then, a high frequency magnetic pulse shifts them from their straight positions
    • A special antenna listens for the resonance signal each proton gives off
    • Characteristically, they go back to their original positions
  • 41. MR
    • TR/TE
    • Marrow
    • CSF/H20/Disc
    • TR - Repetition Time - length of time needed for protons to realign
    • TE - Echo Time - measure of time for energy absorbed from the radiowave pulse to be reabsorbed
    T2 Long Dark Bright T1 Short Bright Dark
  • 42. MR
    • Bright ( SI )
    • Fat
    • Hemorrhage
    • H2O/ Edema (T2)
    • Dark ( SI )
    • Air
    • Cortical Bone
    • Flowing Blood
    • Fibrous Tissue
    • H2O/ Edema (T1)
  • 43. MR Precautions
    • Strong Magnetic Field-
    • Determine whether patients have:
    • aneurysm clips-head
    • pacemakers
    • artificial valves
    • exposure to metal shards
  • 44.  
  • 45.  
  • 46.  
  • 47.  
  • 48. Interventional Radiology
    • Can be diagnostic or therapeutic
    • Procedures:
    • Angiography-vessel visualization
    • Tube, line, stent, device placement
    • Biopsy
    • Complications:
    • Hemorrhage, embolus, infection
  • 49. Interventional Radiology continued
    • Radiopaque dye (absorbs the x-ray beam) is administered via a catheter.
    • X-ray images reveal the anatomy to be normal or abnormal.
    • Abnormal features include stenosis (blockage), abnormal vessels (AVM), and Tumor Blush
  • 50. Interventional Radiology continued
    • Contrast
    • Same dye used in other x-ray studies, IVP’s, CT’s
    • Dye-clear
    • Metallic taste
    • Warm flush feeling
    • Nausea
    • Ask about prior administration, allergies, and renal function
  • 51.  
  • 52.  
  • 53. Nuclear Medicine
    • A small amount of a radioactive isotope is administered to the patient – injected intravenously, inhaled or swallowed. These isotopes attach themselves to certain molecules in the body. Images are obtained to determine the abnormality.
  • 54. Nuclear Medicine continued
    • Bone scan Tec 99m – 4 hours
    • Same amount of radiation as a CXR
    • Isotope excreted in urine
    • Images obtained initially and then 3 hours later. Actual scanning time 30-40 minutes
  • 55. Nuclear Medicine continued
    • Bone Scan Increased uptake in:
    • Acute Fractures
    • Metastatic Disease
    • Growth Plates
  • 56. Nuclear Medicine continued
    • Scans
    • Gallium – infection
    • Hepatobiliary – evaluate liver and gallbladder function and anatomy
    • Liver/Spleen – shape, size, position of organs
    • Thyroid scans – special instructions-
    • discontinue thyroid medication, no I.V. contrast, no seafood or Iodine containing products
  • 57. Nuclear Medicine continued
    • V/Q scan evaluate air and blood flow to lungs
    • TC99m-MAA injected intravenously
    • Xenon-133 inhaled via mask
    • Test for PE, acute or chronic, pre-op lung reserves, effects of granulomatous lung disease, post-op complications, emphysema, heart shunts, congenital abnormalities
  • 58.  
  • 59.  
  • 60. Mammography
    • Film/Screen Technique - lower radiation dose
    • 2 views – craniocaudal, cephalad
    • Initial screening at age 40 unless high risk or symptomatic
    • Follow up with Ultrasound, MR (?)
  • 61.  
  • 62.