Diagnosis and Medical Imaging Technology

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Diagnosis and Medical Imaging Technology

• SNC2D

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Diagnosis

• The interdependence of our organ systems can
  sometimes make it difficult to pinpoint the
  source of a medical problem.

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Diagnosis

• The interdependence of our organ systems can
  sometimes make it difficult to pinpoint the
  source of a medical problem.
• Doctors are trained to look for symptoms that are
  characteristic of specific problems.

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Diagnosis

• The interdependence of our organ systems can
  sometimes make it difficult to pinpoint the
  source of a medical problem.
• Doctors are trained to look for symptoms that are
  characteristic of specific problems (e.g. swollen
  lymph nodes are a symptom of infection).

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Tools of the Trade

• To collect information about whats going on
  inside the body, doctors may use devices like the
  stethoscope (to listen to the heart and lungs)

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Tools of the Trade

• To collect information about whats going on
  inside the body, doctors may use devices like the
  stethoscope (to listen to the heart and lungs)
  and a sphygmomanometer (to measure blood
  pressure).

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Tests of the Trade

• Doctors may also order tests of material
  collected from the body (such as blood and urine)
  which may be analyzed by a separate lab.

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Tests of the Trade

• Doctors may also order tests of material
  collected from the body (such as blood and urine)
  which may be analyzed by a separate lab.
• E.g. Blood may be tested to determine the levels
  of red blood cells, white blood cells, sugar, and
  hormones the chemicals that carry messages
  through the body to regulate the functioning of
  organs.

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Medical Imaging Technologies

• Diagnostic imaging tests can provide doctors with
  even more information an actual visual picture
  of the structure and functioning of organs.
• However, these technologies are often expensive,
  and the effectiveness of each technology is
  limited by its properties.

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Endoscopy

• An endoscope is a thin, flexible tube that has a
  bright light and a video camera that can be used
  to image the digestive tract, as in a colonoscopy.

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Endoscopy

• An endoscope is a thin, flexible tube that has a
  bright light and a video camera that can be used
  to image the digestive tract, as in a colonoscopy.

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Thermography

• In thermograms, infrared light cameras are used
  to diagnose problems with circulation.
• Normal Raynauds syndrome

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X-Rays

• X-rays are high-energy electromagnetic radiation
  that can easily penetrate soft tissues but cannot
  easily penetrate bone.

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X-Rays

• X-rays are used to check for cancers (e.g.
  mammograms), to diagnose problems in the
  circulatory and respiratory systems, and to check
  for broken bones.
• They are quick, painless, and non-invasive but
  exposure to x-rays can damage cells and increases
  cancer risk.

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Body Scanners

• Note that this is also true for the body scanners
  that are used at airports, especially the new
  naked body scanners.

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Body Scanners

• Since the radiation emitted by these body
  scanners is absorbed at the level of the skin, it
  is your skin cancer risk that is most increased
  and the scans cannot find anything concealed in
  any body cavity.

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Body Scanners

• Since the radiation emitted by these body
  scanners is absorbed at the level of the skin, it
  is your skin cancer risk that is most increased
  and the scans cannot find anything concealed in
  any body cavity.
• Also, like most x-rays, they do not show contrast
  that may be used to identify soft materials (like
  plastics and chemical explosives).

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Body Scanners

• Since the radiation emitted by these body
  scanners is absorbed at the level of the skin, it
  is your skin cancer risk that is most increased
  and the scans cannot find anything concealed in
  any body cavity.
• Also, like most x-rays, they do not show contrast
  that may be used to identify soft materials (like
  plastics and chemical explosives).
• In other words, theyre completely ineffective.

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Computed Tomography

• Computed tomography (CT) scans, also called
  computer-assisted tomography (CAT) scans, use
  x-rays to produce images at different angles
  through the body so that a 3D image can be
  constructed.

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Computed Tomography

• CT scans may be used to diagnose cancers,
  skeletal abnormalities and vascular diseases
  (affecting blood vessels).
• But since CT scans use x-rays, they also increase
  your cancer risk.

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Fluoroscopy

• Fluoroscopy is a technique in which a continuous
  beam of x-rays is used to produce moving images.
  
• It is used to show movement in the digestive
  system (which may require ingestion of a
  high-contrast liquid such as barium) and the
  circulatory system (angiograms).

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Ultrasound

• Ultrasound is high-frequency sound waves produced
  by a device called a transducer that are
  reflected back to the transducer by internal body
  structures.

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Ultrasound

• Ultrasound is high-frequency sound waves produced
  by a device called a transducer that are
  reflected back to the transducer by internal body
  structures.

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Ultrasound

• Ultrasound is used to study soft tissues and
  organs, especially the heart (echocardiograms)
  and especially during pregnancy.
• Because the presence of gas can distort images,
  ultrasound is not often used for imaging the
  respiratory or digestive systems.

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Magnetic Resonance Imaging (MRI)

• Magnetic Resonance Imaging (MRI) is a technique
  that uses strong magnets and radio waves that
  interact with the hydrogen atoms in your body
  (esp. in water). A computer is used to construct
  an image from the signal received from the atoms.

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Magnetic Resonance Imaging (MRI)

• MRI is used to image the structure and function
  of the brain, heart, soft tissue, and the inside
  of bones to diagnose cancers, brain diseases,
  and problems with the circulatory system.
• But it is also extremely expensive and the
  availability of machines/technicians is limited.

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Positron Emission Tomography (PET)

• PET scans are a type of nuclear medicine is which
  a patient is given a radioisotope that emits
  positron radiation the radioisotope is attached
  to a chemical absorbed by certain tissues or
  organs.
• It is used to detect cancers,
• heart disease,
• and some brain disorders
• (such as Alzheimers).

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More Practice

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