DIAGNOSTIC IMAGING

Justin Williams Sarah Spring

November 27th 2009

(1)

Table of Contents

o What is medical imaging?o X-Rayso MRIo ULTRASOUNDo CTo Conclusiono Referenceso Questions

What is medical Imaging?

Processes and techniques used to develop

images of the body to find disease and injury

Four most widely used types are :o X rayo CTo MRIo Ultrasound

X-Rays

General

o Uses electromagnetic radiation to form images

o 1st form of medical imagingo Exposes patient to some radiation

X-Rays

How does it Work?

1. Electricity accelerates electrons in vacuum tube2. Electrons crash into metal source and x-ray released3. X rays strike target4. X rays travel through target and hit film behind target5. Image created in film is developed

X-Rays

Discovery

o Discovered accidently by Wilhelm Rontgen in 1895o Was experimenting with devices called Crookes tubeso Excited electrons in tubes created x-rays when they hit

glass wallo Screen 1 meter away had green glowo Rontgen concluded glow was caused by rays called “X”o Later used X-rays to create image of his wife’s hand

finding medical use

(2)Rontgen’s 1st X-ray image

X-Rays

Uses

o Image teeth and Boneso Chest X-rays to show pneumonia, lung cancer, fluid in

lungso Kidney Stoneso Arteries and vein images if contrast media substance

used

(3)

X-Rays

Advantages

o Safeo Okay for most peopleo Widely availableo Relatively Cheapo Quick Process

Disadvantages

o Radiation still usedo Caution with pregnancyo Requires shieldingo Images lack detail and

sensitivity

MRI

What it iso First used in 1967, Nottingham University

in Englando Noninvasive medical test.o Used to diagnose and treat medical

conditions.o Image is produced by a powerful

magnetic field, radio frequency pulses and a computer, which creates detailed pictures of organs, soft tissues, bone and virtually all other internal body structures.

MRI

When is it usedo Detects disease throughout the body.o Can see bleeding or swelling of the brain.o Brain aneurysms.o Strokes.o Brain tumors.o Inflammation or tumors of the spine.o Evaluates structure of heart and aorta.o Provides accurate information of bones,

soft tissues and joint structures.

MRI

Advantages

o Noninvasiveo Enables you to see

abnormalities obscured by bone

o Less likely to produce allergic

reactiono Fast alternative to X-ray

for Diagnosing problems of the

heart And blood vessels

Disadvantages

o Poses almost no risk

o Implanted medical devices containing metal may malfunction or cause problems

o Costs more and may take more time

MRI

o http://www.youtube.com/watch?v=6_2D3Lh1v74

Ultrasound

What it iso 1961 Ian Donaldo Also known as Ultrasound scanning or a

Songraphy.o These images are produced by exposing the part

of the body to high frequency sound waves.o Noninvasive.o Captured in real time, can show blood flowing

through blood vessels.o Also can show structure and movement of

body’s internal organs.

Ultrasound

When is it usedo Help physicians evaluate pain, swelling

and infections.o Examines bodies internal organs such as;

heart, blood vessels, liver, spleen, gallbladder, pancreas, kidneys, etc.

o Guide procedures.o Diagnose heart conditions.

Ultrasound

Advantages

o Noninvasiveo Widely availableo Easy to useo Uses no ionizing

radiationo Gives clear picture of

soft tissueo Real time imaging,

preferred for monitoring

unborn babies

Disadvantages

o For standard Ultrasound, there are no known harmful risks to humans

CT

General

o Computerized tomographyo Form of X-ray technologyo Uses computer processing to produce

detailed images of body parts from multiple views/angles

CT

How Does it Work

1. X-ray source rotates around patient2. Sensors opposite the x-ray source capture the x-ray3. Many scans taken as patients moved through 4. Computer process and creates detailed final image by

combining the multiple images

(4)

CT

Discovery

o Proper computer technology/processing was needed firsto 1st medically useful device invented in 1967o Built by EMI Laboratoryo Required 2.5 hours of computer processing time to

produce imageo Processing times improved with better computers

CT

Uses

o Head/Brain CT to find clots, injury, tumouro Chest scan CT images which are much better than X-ray

because of increased detailo Coronary artery/heart scan to diagnose heart diseaseo Detailed Bone images to show fractures

(5) CT scan of cancerous tumour in lung (top view)

CT

Advantages

o Detailed 3D imageso Images viewed from

different angle/planeo Can focus on Specific

Areao Used to screen/detect

diseaseso Can be used to avoid

invasive procedures

Disadvantages

o Expensiveo Not widely available

outside wealthier countries

o Much higher radiation exposure versus regular x-ray

Conclusion

Diagnostic Imaging plays a significant role in everyone’s health. With this technology we are able to detect abnormalities that can be fatal. Everything harmful from bone fractures, internal bleeding and cancer, to signs of life in an unborn baby can be detected through these types of imaging.

References

1. http://www.nuh.nhs.uk/diagnosticimaging/images/3x3.gif

2. http://en.wikipedia.org/wiki/File:Anna_Berthe_Roentgen.gif

3. http://www.boreme.com/boreme/funny-2005/kermit-visits-doctor-p1.php

4. http://en.wikipedia.org/wiki/File:64_slice_scanner.JPG5. http://health.allrefer.com/pictures-images/lung-mass-

right-upper-lobe-ct-scan.html

References

o http://en.wikipedia/org/wiki/x-rayo http://en.wikipedia.org/wiki/X-ray_compu

ted_tomographyo http://www.nlm.nih.gov/medlineplus/xray

s.htmlo http://www.nlm.nih.gov/medlineplus/ency

/article/003330.htmo http://www.radiologyinfo.org/en/info.cfm?

pg=bodymro http://www.medicinenet.com/mri_scan/ar

ticle.htmo http://www.radiologyinfo.org/en/info.cfm?

PG=genuso http://www.ob-ultrasound.net/

References

o http://www.nasa.gov/vision/earth/technologies/16feb_ultrasound.html

o http://www.youtube.com/watch?v=6_2D3Lh1v74

Thank You

QUESTIONS?