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mammography

  1. mammography?
  2. • first used to examine breast tissues by the german surgeon- ALBERT SALMON . • a mammogram is a x ray exam of breast to detect and evaluate any changes in the breast.
  3. indication • breast cancer-the first symptoms of breast cancer usually appear as an area of thickened tissue in the breast. other symptom-pain, resdness, nipple discharge, inverted nipple, change in the size o shape of the breast. stages of breast cancer- *stage 0= known as ductal carinoma in situ, (cells that line the milk ducts of the breast have become cancer). *stage 1= tumors measures upto 2 c.m across. it has not affected any lymph nodes. * stage 2 = it has started to spread to nearby nodes , has not spread to the lymph nodes. *stage 3 = the cancer has spread to distant organs.
  4. • breast lump: localized swelling. • nipple discharge. • breast pain. • follow up for previously evaluated mammographic findings.
  5. contra-indication • pregnancy • radiation therapy to chest/mediastinal • active collagen disease: immune system causes inflammation in our collagen, it is the main structural protein found in various connective tissue.
  6. mammography x- ray tube • target materials consists of- molybdenum(42) rhodium(45) • molybdenium is the best material to be used in mammography. • allows production of low energy spectrum of radiation • low kvp(26-40)
  7. filtration • materails that are placed in the path of the x ray beam in order to absorb those x ray with low energy. • molybdenum- best used for lower kvp • rhodium • yttrium (39)
  8. collimation: • used to shape radiation field. • less scatter. • smaller exposed area, better for patient dose.
  9. breast compression • breast is compressed using a rigid transparent plastic compression plate. • breast is compressed for better spatial resolution. • spatial resolution is the ability of an imaging system to diffrentiate between two near by objects. • reduce movement blur.
  10. views : • standard view:craniocaudal view(cc view), 45 degree lateral oblique(MLO). • additional view: extendd CC view,true lateral view, axillary view, cleavage view, paddle compression view, magnification view, eklund view.
  11. what is CC View? • the mammography equipement is positioned with the x ray beam axis pointing vertically downwards. • the women faces the machine, with her arms by her side. • she is standing and is rotated 15-20 degrees to bring the side under examination close to the horizontal breast - support table. • the table is at the level of infra mammary crease(lower boundary of breast)
  12. • the nipple should be in the midline of the breast and in profile. • the women head is turned away from the side under the examination. • the breast is lifted up and rotated medially 5-10 degrees so that the nipple is just medial to the midline of the film. • as the hand is removed, the breast is compressed firmly to a level that the women can tolerate. • a remote cotrolled foot compression device allows this to be achieved more easily. • compression must be released as soon as the exposure ends.
  13. MLO • allows visualization of the largest amount of breast tissue. • the mammographic equipement is routinely angled at 45 degrees from the vertical. • the women arm is placed on the top of the table with elbow flexed and dropped behind it. • the table height is adjusted so that the lower border of the breast is 2-3 c.m above the edge of the film. • the breast is gently extended upwards and outwards to ensure it contacts the breast - support table. • the compression plate is applied. • when the compression is almost complete, the breast is checked for skin folds and radiographer’s hand is removed.
  14. 45 degree lateral oblique(MLO). • lateral side of the breast is probably the most common place for pathological changes to occur. • for an ML view, the tube emitting the x-ray is medial and the detector plate is lateral. • for the LM view, the tube is lateral and the detector is placed medially. • lateral views are extremely useful in determining the exact location of an abnormality in the breast. • ML view is best for lesions located in the central or lateral breast • LM view is best for evaluating medial lesions.
  15. extended cranio-caudal view: • the routine CC view will not showmany abnormilities in the upper quadrant of the breast, which will be demonstrated on the medio-lateral oblique projection. • as all lesions must be demonstrated on two projections, this extended crnio-caudal projection is useful for demonstrating the outer quadrant, axillary tail and axilla. • the women stands close to the equipement, with her breast aligned slightly side of the midline of the breast support table. • the breast is lifted gently and placed on the table
  16. • the women is then encourged to lean 10-15degrees laterally. • compression is applied , the exposure is made and compression released immediately.
  17. magnification view • A magnification view in mammography is performed to evaluate and count microcalcifications. • This allows the acquisition of magnified images of the region of interest. • magnified projections are done in the cranio-caudal and mediolateral projections. • the women is placed in the position for the lateral and cranio caudal projections in turn. • it is important to realize that the field will cover only the half of the breast under examination. • Provides additional information on margins, satellite lesions, and microcalcifications. Can also be useful for asymmetric tissue .
  18. cleavage view • A cleavage view (also called "valley view") is a mammogram view that depict the posteromedial portion of both breasts (the “valley” between the two breasts) by placing them on the cassette at the same time and pulling them anteriorly. • Modified CC view that improves visualization of area between breasts. Both breasts are positioned on the detector.
  19. axillary view • An axillary view (also known as a "Cleopatra view“) is a type of supplementary mammographic view. It is an craniocaudal view for better imaging of the lateral portion of the breast to the axillary tail. • This view allows imaging of the axillary tail of the breast. It resembles the ML view but allows evaluation of breast tissue more laterally oriented.
  20. spot view • A spot view (also known as a spot compression view or focal compression view) is an additional mammographic view performed by applying the compression to a smaller area of tissue using a small compression paddle, increasing the effective pressure on that spot. This results in better tissue separation and allows better visualization of the breast tissue in that area.
  21. patient preparation? • give verbal instruction. • patient should refrain from using lotions, powder, and deodrants the day of examination. • patients clothing from waist up will be removed.
  22. abnormalities: • cysts: fluid filled sacs. • calcification: deposition of calcium. • fibroadenomas: benign tumors.
  23. Why is compression important in mammography? • Decreases radiation dose • Separates glandular tissue • Decreases superimposition of tissue • Improves resolution or clarity of the image • Increases contrast to visualize subtle differences in tissue • Reduces scatter radiation
  24. digital mammography • Digital mammography is a specialized form of mammography that uses digital receptors and computers instead of x-ray film. • the X-ray film is replaced by solid-state detectors that convert X-rays into electrical signals. • The electrical signals are used to produce images of the breast that can be seen on a computer screen or printed on special film similar to conventional mammograms. • also called full-field digital mammography (FFDM)
  25. Tomosynthesis (3D Mammography) • Tomosynthesis or “3D” mammography is a new type of digital x-ray mammogram which creates 2D and 3D-like pictures of the breasts. • This tool improves the ability of mammography to detect early breast cancers. • The images include thin one millimeter slices. • The “3D” images reduce the overlap of breast tissue, and make it possible for a radiologist to better see through your breast tissue on the mammogram.
  26. • Multiple studies have shown that “3D” mammography increases the detection of breast cancer by approximately 25%, and decreases the number of false positive call backs by approximately 15%.
  27. Galactography or ductography • is a medical diagnostic procedure for viewing the milk ducts. • The procedure involves the radiography of the ducts after injection of a radiopaque substance into the duct system. • The procedure is used for investigating the pathology of nipple discharge.
  28. ADVANTAGES • It is time-efficient. • It is easier to see slight differences between tissues. • It requires lower average radiation dosage. • Reduces the risk of dying from breast cancer. • Reduces the risk of having to undergo chemotherapy.
  29. LIMITATION • they are no 100% accurate in showing if a women has breast cancer. • mammograms look normal though breast cancer is present. • mammograms look abnormal een though there is no cancer in breast. • women with dense breasts have more false negative limitations of mammograms.
  30. Xeroradiography/xeromammography • X-ray imaging in which a picture of the body is recorded on paper rather than on film. • a plate of selenium, which rests on a thin layer of aluminium oxide. • Xeromammography is a photoelectric method(electrically charge particle is released within a materia; when it absorbs electromagnetic radiation) of recording an x-ray image on a coated metal plate, using low-energy photon beams, long exposure time, and dry chemical developers. • This process was developed in the late 1960s by Jerry Hedstrom, and used to image soft tissue, and later focused on
  31. Xeroradiography/xeromammography • photoelectric method. • records images without film. • latent image is converted to positive image .
  32. xeroradiography Vs Radiography • elimination of accidental film exposure, economic benefit, reduced exposure to radiation dose. • it involves neither we chemical processing nor the use of the dark room. • dis:the process of developement cannot be layed and is it to completed within 15mins.
  33. components: • xerographic plate. • corotron. • casette. • toner. • special paper.
  34. xerographic plate. • sheet of aluminium in which a layer of amorphus selenium has been deposited. In addition, there is an interface layer between the selenium and aluminium and an overcoating protecting the selenium surface. • layers: overcoating, selenium, interface, aluminium.
  35. procedure • the first step in xeroradiographic process is to sensitise the selenium the selenium layer by applying a uniform electrostatic(biuld up charges due to conatct with other crges) charge to its surface in the dark .
  36. principle: • the XR plate is charged to a high positive potential by corotron(charging device) • it is then placed in a cassette and used in a manner similar to that with conventional film in its casette. • when x rays strike the selenium, photoconduction(material become more electrically conductive due to absorption of x rays) occurs and this produces a charge image of the part examined. • the image is made visible by bringing into proximity to the plate charged developer or toner particles. • the resultant powder image is subsequently transferred to paper and fused providing an opaque XR interpretation and storage.
  37. process: • plate is sensitizes before the exposure. • the charged plate is placed in a light tight casette and is exposed to x rays. • the x ray reaching the plate cause the photoconductor layer to lose its charge in an amount corresponding to the intensity of x-ray beam. • the uniform charge is thus dissipated and the remainning charge patterns form the ltent electrostatic image.
  38. • the exposed plate is placed on the top of a dark box into which an aerosol of charged tonner particles is sprayed through a nozzle(produces millions of ink droplets used in creating the image) • all toner must be removed before the plate is to be reused. • the plate is exposed to a light source that reduces the bond holding the residual toner to the plate. • a preclean corotron exposes the plate to an altrnating current .
  39. image quality image quality is based on --- • radiographic mottle • sharpness • resolution. • radiographic mottle- depends on film screen mottle and film gradiness. screen mottle depends on structure mottle and quantum mottle.
  40. • radiographic mottle: it is also known as noise. it directly related to the number of x-ray photons. • Fewer photons reaching the image receptor will cause an undesirable fluctuation in image densities, resulting in images with a grainy, or sandlike, appearance.
  41. sharpness • ability to define edge of film. types of unsharpness: geometric unsharpness, motion unsharpness and photographic or system unsharpness. geometric unsharpness: *Two principal factors play simultaneously: the apparent focal spot size and the ratio between object-film distance (OFD) and focus-film distance (FFD). *Fine focal spot sizes will minimise geometric unsharpness, and therefore give more detailed images.
  42. sharpness *Keeping the ratio FFD:OFD high will minimise geometric unsharpness. Motion unsharpness: *is caused by movement of the patient, the detector or the source of X-rays during the exposure. *Movement of the patient can be minimised in a number of ways: immobilizing the patient, asking the patient to keep still or to hold the breath and keeping exposure time short.
  43. photographic unsharpnesss: *result of the detector system employed.
  44. resolution • Resolution is the ability of an imaging system to display two adjacent objects as discrete entities. • Resolution is also known as spatial resolution
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