CT Scanner — Questions and answers

Read the full story

What was the main problem with traditional X-rays before the CT scanner?

Choices

  1. They only showed things in two dimensions, making it hard to see everything clearly. ✓
  2. They were too expensive for most hospitals.
  3. They made loud noises that scared patients.
  4. Doctors did not know how to read them correctly.

Answer: They only showed things in two dimensions, making it hard to see everything clearly.

From page 1

What important idea did Allan Cormack have for seeing inside objects?

Choices

  1. He thought magnets could show internal structures.
  2. He believed math could create a clear image from many X-ray pictures taken at different angles. ✓
  3. He wanted to use special magnifying glasses to see through the body.
  4. He suggested using brighter lights to look inside.

Answer: He believed math could create a clear image from many X-ray pictures taken at different angles.

From page 2

Why was it so hard to build a working CT scanner even with Cormack's mathematical ideas?

Choices

  1. Doctors didn't want to try new machines.
  2. The X-ray data was too small to see.
  3. Early analog computers were not powerful enough to handle all the complex calculations. ✓
  4. There wasn't enough electricity in the workshop.

Answer: Early analog computers were not powerful enough to handle all the complex calculations.

From page 3

What major change helped Dr. Hounsfield finally make the CT scanner work?

Choices

  1. He stopped using any type of computer.
  2. He switched from analog methods to using digital computers. ✓
  3. He decided to draw all the images by hand.
  4. He asked doctors to do the calculations for him.

Answer: He switched from analog methods to using digital computers.

From page 4

How did the first CT scanner prototype collect information from the patient?

Choices

  1. It used many X-ray sources and detectors all at once.
  2. It moved one X-ray and one detector across the patient, rotated a little, and repeated the process many times. ✓
  3. It asked the patient to move in different ways.
  4. It took only one X-ray picture from the front.

Answer: It moved one X-ray and one detector across the patient, rotated a little, and repeated the process many times.

From page 5

What main idea helps the CT scanner see inside the body?

Choices

  1. It uses sound waves to create pictures.
  2. Different parts of the body absorb X-rays by different amounts. ✓
  3. It makes the body glow in the dark.
  4. It only measures the temperature inside the body.

Answer: Different parts of the body absorb X-rays by different amounts.

From page 6

What do the special algorithms, like 'filtered back projection', do for the CT scanner?

Choices

  1. They make the X-ray machine spin faster.
  2. They clean the patient's scanned area.
  3. They piece together all the X-ray measurements to create a clear image, pixel by pixel. ✓
  4. They tell the doctors what medicine to give the patient.

Answer: They piece together all the X-ray measurements to create a clear image, pixel by pixel.

From page 7

What did the very first clinical CT scan in 1972 successfully show?

Choices

  1. A broken arm bone in a child.
  2. A clear image of a cyst in a woman's brain. ✓
  3. A picture of the patient's heart beating.
  4. That the machine was not working correctly.

Answer: A clear image of a cyst in a woman's brain.

From page 8

How did CT scanner technology improve over time?

Choices

  1. It became much slower and showed fewer details.
  2. It evolved to be faster and have much better image quality. ✓
  3. It stopped using X-rays altogether.
  4. It became so small that nobody could find it.

Answer: It evolved to be faster and have much better image quality.

From page 9

How has the CT scanner significantly changed medicine?

Choices

  1. It made doctors write more prescriptions.
  2. It helps doctors understand how to build machines.
  3. It provides clear views inside the body for earlier diagnosis and better treatment, saving many lives. ✓
  4. It helps patients read books about their health.

Answer: It provides clear views inside the body for earlier diagnosis and better treatment, saving many lives.

From page 10