L3

Question 1

Medical Image

Answer 1

The set of techniques that
noninvasively produce images of
the internal aspect of the body

Question 2

Image Quality

Answer 2

It refers to how well the image conveys anatomical or functional information to the interpreting
physician such that an accurate diagnosis can be made.

Question 3

4 factors of Image Quality

Answer 3

1. Spatial Resolution
2. Contrast Resolution
3. Convolution
4. Physical Mechanisms of Blurring

Question 4

Spatial Resolution

Answer 4

• Spatial resolution describes the level of detail that can be
  seen on an image.
• relates to how small an object can be seen on a
  particular imaging system

Question 5

Contrast Resolution

Answer 5

It refers to the ability to detect very subtle changes in gray
scale
- t pertain to the signal-to-noise
ratio (SNR) in an image.

Question 6

Convolution

Answer 6

The integral calculus procedure that accurately
describes mathematically what the blurring process does
physically.

Question 7

Physical Mechanisms of Blurring

Answer 7

It refers to the process of reducing the spatial resolution of an image produced by an optical device by accidental defocusing

Question 8

Accuracy

Answer 8

It refers to the closeness of something to the center/target

Question 9

Precision

Answer 9

It refers to the closeness of things to each other

Question 10

5 Sources of Image Noise

Answer 10

1. Grain Noise
2. Electronic Noise
3. Structured Noise
4. Anatomical Noise
5. Quantum Noise

Question 11

Grain Noise

Answer 11

• The increase in the optical density of an image results in the increase of the density of the reduced silver halide crystals that adheres to the film

Question 12

Electronic Noise

Answer 12

It refers to the added electron noise in the signal that can come from thermal noise, shot noise, and others.

Question 13

Structured Noise

Answer 13

It is about the different offset noise and gained characteristics that a group of detectors elements read out because each channel uses its own
amplifier circuits and these circuits cannot be perfectly
tuned with respect to each other.

Question 14

Anatomical Noise

Answer 14

It refers to the patient anatomy that is present on the image but is not important for the diagnosis

Question 15

Quantum Noise

Answer 15

• Quanta refers to the number of particles that can be counted
• Low quanta in imaging modalities that is based on ionizing radiation results in quantum noise

Question 16

What is the picture element of an image?

Answer 16

Pixels

Question 17

What is the volume element of an image

Answer 17

Voxel: gives depth to the image

Question 18

2 categories of an Image Data Format

Answer 18

First, the formats intended to standardize the image generated by diagnostic modalities: DICOM

Second, the formats aim is to facilitate and strengthen post-processing analysis: Analyze, Nifti, Minc

Question 19

4 Imaging Data Format

Answer 19

1. Analyze
2. Nifti
3. Minc
4. DICOM

Question 20

Analyze

Answer 20

• File extension: .img & .hdr
• created in Mayo Clinic, USA at the end of 1980
• Designed for multidimensional data

Question 21

Nifti

Answer 21

• FIle Extension: .nii
  -Stands for: Neuroimaging Informatics Technology Institute
• created at the National Institute of Health (NIH) in the 2000s
• AKA Revised Analyze Format
• Intended to create a format for neuroimaging
  maintaining the advantages of the Analyze format, but solving the weaknesses

Question 22

Minc

Answer 22

• File Extension: .mnc
• developed at the Montreal Neurological Institute
• Intended to provide flexible data format

Question 23

DICOM

Answer 23

• File Extension: MPEG and such
• AKA Digital Imaging and Communications in Medicine
• Established by the American College of Radiology and
  the National Electric Manufacturers Association

Question 24

Phoenix

Answer 24

• It is capable of extracting the protocol and replicate it for a new acquisition in DICOM