Imaging Science ch11

Digital Imaging in Rad

When was the transistor developed?

1948

What is a transistor?

an electronic switch that allows or does not allow electronic signals to pass - now computers can store programs

When was the microprocessor developed?

1971

What was built in 1943?

The colossus - used to check German military codes

What are types of computers?

PC as a desktop, laptop, tablet, wristwatch

What are the two principle parts of the computer?

Hardware

SoftwareW

Hardware

nuts, bots, and chips of the system; CPU - Central Processing Unit, all input/output devices

Software

Computer programs that tell the hardware what to do; how to store and manipulate data

ex: input

mouse, keyboard (to IN-PUT information)

ex: output

monitor (OUTPUT screen information)

Computer Language

higher-level languages allow for input of english-based instructions

Computer language is translated how?

the instructions are translated by the computer into 1s and 0s

bit

a binary digit (0 or 1)

byte

8 bits combined - represents one character, digit, or other value

2 bytes = ?

a word

Software (computer language)

instructions written in computer language that guides the computer through designated operations

CP = ?

Computer Programs = a sequence of software instructions

System software = ?

operating system (OS); Windows, MAC-OS, Unix, Linux

Operating System (OS)

Loaded into the computer by a bootstrap program, manages all the other programs in a computer

(rebotting = bootstrap proram starting, “REBOOT”)

Application Software = ?

programs written to permit the computer to perform a specific task (word, excel, turbotax, candy crush)

CPU = ?

Central Processing Unit (microprocessing) - consists of control unit and arithmetic/logic unit (ALU)

Control Unit = ?

Tells computer how to carry out software instructions , directs hardware to perform task

Speed of tasks

gigahertz (GHz) billion/sec

ALU =?

performs arithmetic/logic functions

how is memory distingued by storage?

by functions (memory more active, storage more archival)

RAM aka

Random Access Memory

how is memory / RAM usually expressed?

Megabytes, gigabytes, terabytes

ROM

Read Only Memory - contains information from manufacturer (firmware) - cannot be written or ERASED

What tells the processor what to do at start-up?

one ROM chip; - this is bootstrap

What does another ROM chip do?

helps processor transfer information between screen, printer, and all other devices

what is a Secondary memory

hard disk drives, CD ROM, Flash drives, DVD ROM, SSD, RAID, Icloud, Google drive, Dropbox

What is a motherboard?

aka System Board - Contains microprocessor, coprocessor chips, RAM chips, ROM chips, other memory and expansion slots (for other circuit boards)

What are output device?

devices that translate computer information into a form humans can understand

What are common OUTPUT devices?

display screens (monitor), printers - multifunction devices and audio output devices (speakers)

What type of monitors are used?

LCD, LED; no more CRT

What is a terminal?

Used for keyboard for input, monitor for output

What are INPUT devices?

Keyboard, mouse (trackball, joystick, touchpad)

pen-based systems

used in hospitals to enter comments into patient records (aka IPAD)

Source - data - entry devices

scanners, barcode readers, fax machines, imaging systems, audio/video devices, digital cameras, sensors, human biology inout devices (face recognition, thumb print)

Teleradiolology

transfer of image and patient data, uses for communication tech (send images to radiologist)

Modem

modulate/demodulate - converts digital into analog (from sender), then analog to digital (at receiver)

List the fastest to various communication speeds

• Fiberoptic (fastest)

• Cable Modem (very fast)

• DSL (fast)

• ISDN (5x faster than regular phone line)

• Wireless (RF - Speed Varies)

Processing methods

Real Time processing - incoming data immediately processed

What are real time modalities?

CT, DR, FLUORO

DICOM

Digital Imaging and Communications in Medicine - standard method of medical image storage

(common language to allow various computer/software to share information)

PACS

Handles transfer and storage of medical images

What did the FDA approve and when?

Teleradiology - FDA approved viewing of medical images on a mobile device in 2011

What is AI?

Artificial Intelligence - adaptation of computer technology to mimic the human mind in cognitive activities (learning, problem solving)

What are two examples of AI?

Alexa and Siri

What is pattern recognition

Machine learning and deep learning are being applied to medical imaging

How will AI help with workload?

will make image interpretation more efficient, improving speed, accuracy and diagnosis

What does AI remove?

motion, noise, artifacts

CAD

Computer Assisted Detection

ML - Machine learning

the computer is taught to learn by providing it with a large number of “training” images

Supervised Learning

Training data images include identified normal and abnormal images (telling AI what image is normal and which are abnormal)Un

supervised training

normal and abnormal information withheld (not telling)

• system will identify abnormalities on its own

• will categorize its findings as a percentage of normal and abnormal

What does Machine Learning require?

required thousands of images

Patter Recognition

unsupervised training has a algorithms to identify similar clustering of data - data mining

Decision Tree

- algorithms - branch to cluster, smaller branches to a leaf (the diagnosis)

Anomaly detection

incidentalomas - accidental findings

Deep learning

a co-set / subset to machine learning

Neural Network

Closely resemble the structure and function of the human brain

What does Nural Networks contain?

contain neurons (nodes) that transmit information from one later of the network to the next

ROI

Region of interest

Quantum Computing

• will be able to solve certain types of problems faster than classical computers

• may solve impossible problems

• currently, can not perform a useful task faster, cheaper, or more efficiently than classical computers

AI Security

• An attacker with access to medical images can alter the contents to cause a misdiagnosis

• the attacker can add or remove evicense of some medical condition

What may an AI attacker add or remove?

heart disease, blood clot, tumor, cancer, infections, aneurysms

What are motives for AI attackers?

• Political

• Ransomeware

• insurance fraud

• falsifying research evidence

• sabotaging another company’s research

• job theft

• terrorism, assassination and murder