12. Medical Imaging Technologies

Q: What is medical imaging?]

• The use of technology to create images of organs and tissues inside the body

• for diagnosis and treatment.

An X-ray

uses?

cannot penetrate?

what appears white?

An X-ray

• uses high-energy radiation that can easily penetrate materials such as skin and tissues

• cannot easily penetrate metals and bone.

• X-rays are absorbed by dense structures such as bone,

• the bones appear whiter than other structures

A radiograph ?

• A radiograph is produced when X-rays pass through the body

• to produce an image.

• One risk of X-rays?

• DNA damage and increased cancer risk.

what is Radiotherapy?

how does it work?

Radiotherapy

• X-rays are used to treat cancer.

• The X-rays damage the DNA and either kill the cancer cells or prevent them from multiplying.

• During radiotherapy, a beam of X-rays is directed at a tumour so that there is minimal damage to healthy normal cells.

• Radiotherapy may be combined with other forms of cancer therapy, including surgery and chemotherapy.

what is FLUOROSCOPY ?

Doctors sometimes make patients drink?

to do what?

Used for:?

FLUOROSCOPY

• Like an X-ray video

• Shows organs (stomach, intestine, colon) moving

Doctors sometimes make patients drink

• barium

• iodine

• to see organs better.

Used for:

• Digestive system

• Blood vessels (angiogram)

What is an angiogram?

• A fluoroscopy image of blood vessels of the heart and brain using contrast dye to see the organ clearly.

• In a coronary angiogram?

• cerebral angiogram?

In a coronary angiogram,

• a special dye is injected into an artery in the groin.

• This dye enables doctors to visualize the blood flow.

In a cerebral angiogram

• shows any blockages in the blood vessels in the brain,

• which can lead to a stroke.

ULTRASOUND

• Uses ?

• to produce?

Good for: ?

ULTRASOUND

• Uses high-frequency sound waves

• NO radiation

• to produce images of the body

  tissues and organs.

Good for:

• studying Soft tissues and major organs

• Pregnancy (babies!)

• Heart problems

Why is ultrasound safe in pregnancy?

• It does not use radiation.

One limitation of ultrasound?

• Sound waves cannot penetrate bone or gas.

CT (CAT) SCAN

• how does it work?

• radiation compared to regular X-ray?

🧠 CT (CAT) SCAN

• Uses many X-rays

• Taken from different angles

• Makes a 3D image

• image bone, soft tissue, and

  blood vessels at the same time.

• ⚠ More radiation than regular X-ray

What is a CT/CAT scan commonly used for?

What is a CT scan commonly used for?

• diagnose cancer,

• vascular diseases. (veins, arteries)

• brain bleeding

• skeletal problems.

Magnetic Resonance Imaging

(MRI)

• Uses ?

Best for: ?

❌ Can’t be used if ?

Magnetic Resonance Imaging

• Uses magnets + radio waves

• NO radiation

Best for:

• Brain

• Spinal cord

• Soft tissues

❌ Can’t be used if

• patient has metal inside body

MRI diagnoses?

Machine visual?

• used to diagnose forms of cancer, brain diseases, and cardiovascular conditions.

• An MRI machine is about the size of a car and looks like a hollow cylinder.

NUCLEAR MEDICINE ?

Radioisotopes are also used to trea

NUCLEAR MEDICINE / PET

• Imaging that uses radioisotopes to show organ function not just structure

Radioisotopes are also used to

• treat disease.

• (thyroid,

• prostate

• breast cancer)

What is Positron Emission

Tomography (PET) used for?

• may be combined with ?

• to produce ?

• PET scans are a type of _____ medicine
  

What is Positron Emission

Tomography (PET) used for?

• Detecting cancer,

• heart disease,

• and brain disorders. (alzheimers)

• may be combined with a CT scan

• to produce cross-sectional images

• PET scans are a type of nuclear medicine

BIOPHOTONICS & ENDOSCOPY

• Uses light

• Special cameras to?

BIOPHOTONICS & ENDOSCOPY

• Uses interactions of light with cells and tissues

• Special cameras to see and treat abnormal cells

Endoscopy: ?

Endoscope:

• A flexible tube with a light and a camera

• used to see inside the body, digestive tract, and during surgery