Computer Basics: Image Formation & Management Systems

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Questions and Answers

Which carrier is considered the sturdiest for data transmission?

Satellite Wireless

Coaxial cables (correct)

Fiber optics

Twisted pair wires

What is the bandwidth range for twisted pair wires in a hospital's Intranet network?

1 to 5 Gbps

100 to 1000 Mbps

1 to 10 Mbps

10 to 100 Mbps (correct)

What is the primary function of a Network Interface Card (NIC)?

To store program data permanently

To supply electricity to the system

To connect the PC to other computers in a network (correct)

To manage input and output devices

What are the transmission capabilities of fiber optics?

Greater than 10 Gbps Signup and view all the answers

Which of the following is a characteristic of a Hard Disk Drive (HDD)?

It requires a constant power source Signup and view all the answers

Which of the following is NOT a characteristic of wireless connections?

Utilizes physical cables Signup and view all the answers

Which storage technology is typically used in modern PACS systems for image storage?

Cloud Drives Signup and view all the answers

What is the primary function of a computer router in a network?

To receive, analyze, and forward data packets Signup and view all the answers

What essential service does a server provide in a computer network?

Services to other computers on the network Signup and view all the answers

What distinguishes a thin client from a regular PC?

It requires constant communication with a server Signup and view all the answers

What is a significant disadvantage of a star topology PACS system?

Server failure can halt the storing of exams Signup and view all the answers

How does a web-based PACS system primarily differ from traditional client-based PACS systems?

Allows access from anywhere in the world Signup and view all the answers

What is a key component of network security in PACS systems?

Encryption of data before transmission Signup and view all the answers

Which of the following accurately defines telemedicine?

Diagnosis and treatment delivered via telecommunications Signup and view all the answers

What is a benefit of remote monitoring in telehealth?

Ability to serve both rural and urban populations Signup and view all the answers

What is a thick client computer workstation capable of in radiology?

Managing files independently and performing high level processing tasks Signup and view all the answers

Which of the following best describes the TCP/IP protocol?

A communication protocol designed for interconnecting network devices on the internet Signup and view all the answers

Which statement accurately characterizes the OSI model?

It is a universal model consisting of seven layers with bidirectional data flow Signup and view all the answers

What distinguishes an IP address from a MAC address?

IP addresses are used for internet routing, while MAC addresses are used only in local communications Signup and view all the answers

What does a gateway do in a network?

It serves as a node connecting two networks with different transmission protocols Signup and view all the answers

What is one of the primary functions of the Hospital Information System (HIS)?

Managing the Admission, Discharge and Transfer of patients Signup and view all the answers

What is a key benefit of using an Electronic Medical Record (EMR) in a hospital?

Facilitates real-time access to patient information Signup and view all the answers

What do the standards of Health Level 7 (HL7) primarily focus on?

Clinical and administrative data transfer protocols Signup and view all the answers

How does the Dossier Santé Quebec (DSQ) improve health care in Quebec?

By facilitating easy access to patients' medical information across regions Signup and view all the answers

What advantage does the Hospital Information System (HIS) provide concerning drug usage?

Improves monitoring and reduces adverse drug interactions Signup and view all the answers

What is the primary function of the Radiology Information System (RIS)?

Track and schedule patient radiology appointments. Signup and view all the answers

Which system does not manage or store images but focuses on radiology data?

Radiology Information System (RIS) Signup and view all the answers

What feature of a PACS ensures that all patient images can be recovered in case of a failure?

Redundant Array of Independent Disks (RAID) Signup and view all the answers

What communication standard is primarily used between the HIS and the RIS?

HL7 Signup and view all the answers

Which of the following accurately describes the role of DICOM in medical imaging?

It standardizes communication between medical imaging devices. Signup and view all the answers

What is a primary advantage of using a client/server-based PACS system?

Images can be accessed simultaneously from multiple users Signup and view all the answers

What is a significant disadvantage of a web-based PACS system?

The system's functionality may be limited due to the absence of local software installation Signup and view all the answers

Which of the following is considered a disadvantage of a client/server-based PACS system?

Server dependency creating a single point of failure Signup and view all the answers

What storage technology are hospitals increasingly using for long-term archival of medical images?

RAID systems Signup and view all the answers

What is a limitation of using JPEG format in a web-based PACS system?

It cannot store high-resolution images Signup and view all the answers

What does the Cross Document Sharing Mediator (XDS-M) server facilitate in the DSQ system?

It allows centralized storage and retrieval of images and reports. Signup and view all the answers

How does the RID contribute to radiology services within the DSQ system?

By facilitating quicker access to diagnostic images and reports. Signup and view all the answers

What is a notable benefit of utilizing the DI-r or RID according to the information provided?

It decreases patient travel time and the number of transfers between facilities. Signup and view all the answers

What triggers the request for previous exams when a radiology examination is scheduled?

A message created in the hospital's HIS or RIS. Signup and view all the answers

What impact does the DSQ system have on emergency cases according to the benefits listed?

It facilitates faster handling of emergency cases. Signup and view all the answers

What effect does increasing the atomic number (Z) of an object have on x-ray transmission?

Decreases transmission Signup and view all the answers

What characterizes a radiolucent object in the context of x-ray imaging?

It transmits x-rays Signup and view all the answers

What is the primary factor that controls the contrast of an x-ray image?

Tissue density Signup and view all the answers

How does tissue density impact the attenuation of x-rays?

Denser tissues absorb more x-rays than less dense tissues Signup and view all the answers

How does increasing the thickness of an object affect x-ray absorption?

Increases absorption Signup and view all the answers

Which of the following statements is true about the wavelength of x-rays?

X-rays are characterized by wavelengths shorter than visible light Signup and view all the answers

What is one of the factors that influences whether x-ray photons are absorbed or transmitted?

Density of the object Signup and view all the answers

What is the purpose of contrast media like iodine and barium in imaging?

To increase the density of soft tissue organs for better visibility Signup and view all the answers

Which of the following types of tissue generally has the highest attenuation of x-rays?

Bones Signup and view all the answers

What occurs to an x-ray beam as it travels through matter?

It undergoes attenuation, reducing its intensity Signup and view all the answers

What happens during coherent scattering with low-energy x-rays?

The x-ray changes direction without losing energy. Signup and view all the answers

What is the energy threshold for pair production to occur?

Greater than 1.02 MeV Signup and view all the answers

Which statement accurately describes photodisintegration?

It causes the nucleus to emit a nucleon after being excited. Signup and view all the answers

In the Compton Effect, what energy must the incident photon primarily exceed?

The binding energy of the electron Signup and view all the answers

What is the total energy equation for an incident x-ray photon in a Compton scattering event?

$E_i = E_s + E_b + E_{KE}$ Signup and view all the answers

At 80 kVp, how many scattered photons are produced in the forward direction?

50 Signup and view all the answers

What is the relationship between the atomic number (Z) and the probability of photon interaction in the photoelectric effect?

Proportional to Z^3 Signup and view all the answers

What type of tissue does the photoelectric effect occur mainly in?

Bones and positive contrast media Signup and view all the answers

How much more likely is it for x-rays to interact with bone compared to soft tissue based on the given atomic numbers?

6.5 times greater Signup and view all the answers

What is the primary outcome when a photon is completely absorbed by an electron in the photoelectric effect?

Ionization of the electron Signup and view all the answers

How does an increase in Source-to-Image Distance (SID) affect the required milliampere-seconds (mAs) to maintain exposure?

Increase in mAs is required. Signup and view all the answers

If the new distance (DN) is one half of the original distance (DO), by what factor must mAs be adjusted?

¼ times mAsO Signup and view all the answers

What value of mAs would be used if the original (mAsO) was 100 mAs at a SID of 40 inches and the new SID is found to be 60 inches with the same mAs?

156.25 mAs Signup and view all the answers

For a portable X-ray taken at 50 mAs and 60 inches SID, what should the mAs be if the SID is increased by a factor of 1.3?

78 mAs Signup and view all the answers

If the initial SID was 72 inches and the new SID is 40 inches, how does the mAs change using the mAs-related formula?

Decreases to 3.09 mAs Signup and view all the answers

What effect does Source to Image Distance (SID) have on exposure in radiographic imaging?

SID has a direct effect on exposure, but it is not a controlling factor. Signup and view all the answers

How does the Inverse Square Law influence the intensity of radiation exposure as distance increases?

Intensity decreases inversely with the square of the distance. Signup and view all the answers

Which variable is primarily affected when adjusting the kVp in radiographic techniques?

Penetrating power of the x-ray beam. Signup and view all the answers

What is the outcome of increasing the distance from the radiation source in terms of exposure rate?

Exposure rate will decrease due to the Inverse Square Law. Signup and view all the answers

Given a skin dose of 5 Rads/minute at 100 cm, what would be the effect on skin dose when the distance is changed to 150 cm?

Skin dose will decrease based on distance adjustment. Signup and view all the answers

What is the consequence of increasing kVp by 15% in mid-range kVp settings?

It doubles the exposure. Signup and view all the answers

Which factor does NOT influence the choice of SID in practice?

Patient age Signup and view all the answers

If the mAs is halved from 20 mAs to 10 mAs, what kVp adjustment would be necessary to maintain exposure?

80.5 kVp Signup and view all the answers

What directly affects the energy of the x-ray beam and hence exposure?

kVp Signup and view all the answers

When adjusting from 40 mAs to 80 mAs, what kVp adjustment must be made to maintain the exposure?

104 kVp Signup and view all the answers

What is the relationship between mAs and radiation exposure?

mAs is directly proportional to radiation exposure. Signup and view all the answers

Which of the following factors does NOT influence radiation exposure?

Radiographic film type Signup and view all the answers

How does increasing the kVp affect the exposure in radiology?

Increases exposure due to increased photon energy. Signup and view all the answers

What is the purpose of using grids in radiology?

To enhance image contrast by filtering out scattered photons. Signup and view all the answers

What effect does the Anode Heel Effect have on exposure?

It results in varying exposure across the imaging field. Signup and view all the answers

What happens to the primary beam to scatter ratio in the exit beam when kVp is increased?

It decreases Signup and view all the answers

What is the impact of increased filtration on the average beam energy?

It increases Signup and view all the answers

How does contrast media generally affect scatter (SC) in imaging?

It increases scatter Signup and view all the answers

What is the effective atomic number (Zeff) of barium?

56 Signup and view all the answers

Which of the following factors does NOT affect the scatter created by contrast media?

Particle size of the contrast media Signup and view all the answers

What is the primary relationship between Image Contrast (IC) and Subject Contrast (SC)?

IC is directly proportional to SC. Signup and view all the answers

Which factor is essential for generating Image Contrast (IC)?

Minimum required Subject Contrast and IR Contrast Signup and view all the answers

What effect does increasing the kilovolt peak (kVp) have on Subject Contrast (SC)?

Decreases SC by increasing beam penetration Signup and view all the answers

What is a primary requirement for achieving optimal diagnostic value in imaging?

Adequate scale of contrast and sharpness Signup and view all the answers

Which of the following best defines Contrast Resolution?

The ability of an imaging system to differentiate between varying intensity levels Signup and view all the answers

How can the amount of scatter in the remnant beam increase?

By increasing kVp and the part thickness Signup and view all the answers

Which method can effectively reduce scatter reaching the image receptor (IR)?

Using a grid Signup and view all the answers

What does a contrast improvement factor (K) of 1 indicate?

No improvement in image contrast Signup and view all the answers

Which of the following factors can reduce the scatter formation during imaging?

Reduced field size Signup and view all the answers

What effect does increasing the kVp have on scatter radiation?

It increases the percentage of scatter in the forward direction Signup and view all the answers

Which factor leads to an increase in subject contrast (SC) according to the information provided?

Increase in compression Signup and view all the answers

How does the tissue density of an object affect the subject contrast (SC)?

Higher density tissues increase SC Signup and view all the answers

What is indicated if SC1 is greater than SC2 in the context of tissue types?

The first tissue is denser than the second Signup and view all the answers

In comparing soft tissues, which arrangement shows a higher subject contrast with specific tissue densities?

Muscle and Bone Signup and view all the answers

Which scenario would likely decrease the subject contrast (SC) when evaluating different tissues?

Comparing tissues of similar density Signup and view all the answers

What causes magnification in radiographic imaging?

Divergence of the x-ray beam Signup and view all the answers

Which factor is least likely to affect shape distortion in imaging?

Source-to-image distance Signup and view all the answers

What is the result of an increase in object-to-image distance (OID)?

Increase in size distortion Signup and view all the answers

What is true distortion in the context of imaging?

It describes the misrepresentation of the shape of the object. Signup and view all the answers

Which formula correctly expresses the magnification factor (MF)?

MF = Image Size / Object Size Signup and view all the answers

What is the length of the object if an image measures 18 cm long with a magnification of 20%?

15 cm Signup and view all the answers

If the SID is 100 cm and the OID is 60 cm, what is the SOD?

40 cm Signup and view all the answers

Given an object size of 24 cm and a magnification of 20%, what will be the size of the image?

28.8 cm Signup and view all the answers

In a situation where the SID is 40 inches and the OID is 10 inches, what is the SOD?

30 inches Signup and view all the answers

What is the magnification factor if the actual size of an object is 2.5 inches and the image size on the radiograph is calculated?

1.2 Signup and view all the answers

How does an increase in OID affect the magnification factor of an image?

It increases the magnification Signup and view all the answers

What would cause a magnification factor of 2.5 if the SID is set to 100 cm?

OID of 40 cm Signup and view all the answers

What would be the effect on SOD when both the SOD and OID are kept constant while the SID increases?

SOD remains the same Signup and view all the answers

What is the formula for calculating the magnification factor (MF)?

MF = IS / OS Signup and view all the answers

Which condition leads to elongation or foreshortening of an image?

When the image receptor is not parallel to the object. Signup and view all the answers

How can you reduce magnification during imaging?

By increasing the source-object distance (SOD). Signup and view all the answers

What is implied by the Marginal Rays Rule?

Long anatomical parts require diverging rays. Signup and view all the answers

Which positioning technique is NOT recommended to prevent superimposition?

Positioning the patient with internal rotation. Signup and view all the answers

What causes true shape distortion in an image?

Unequal magnification resulting from object alignment. Signup and view all the answers

What is the effect of increasing the source-image distance (SID) on distortion?

It reduces the impact of marginal rays distortion. Signup and view all the answers

Study Notes

Image Formation & Management Systems

Course code: 142-B14-DW
Topic 1: Computer Basics

Specific Learning Objectives

Understand the basic functions of a computer
Define the basic functions of computer hardware components
Identify primary computer tasks performed by technologists
Distinguish between different types of image storage systems
List the methods computers use to communicate
Compare various network topologies
Describe network risks and safeguards for medical imaging computer systems
State the data storage and transmission requirements for PACS
State the applications and advantages of telehealth and telemedicine
Define and describe components of teleradiography

Information Videos

Computer binary codes: [video links available]
Computer hardware and software [video links available]
Hard Disk Drive [video links available]
RAID 0, 1, and 5 [video links available]
Networking [video links available]
DICOM [link available]
Pixel definition [video links available]
ADC [video links available]
Image matrix size and bit depth [video links available]
Radiologist job offer [link available]

A Computer

Input, output, and data processing devices
Processes data into information under a stored program control
Data: unstructured facts
Processes: changes to data
Information: meaningful facts
Stored program: a set of instructions

Important Dates in Computer History

First electronic digital computer designed and built in 1939
First general-purpose electronic computer developed in 1946 (cost $500,000; 18,000 vacuum tubes; one failed every 7 mins)
Transistor invented in 1948; replaced vacuum tubes
Transistor: an electronic switch that controls electronic signals

Computer Language

The Binary Code: The foundation of computer programming/language uses 1s and 0s to process data from input devices
Binary code processing is done by transistors that are on or off
If the circuit is closed and current passes through, the value is 1; 0 if open
Bit: single unit of data; byte: 8 bits storing alphanumeric characters
Decimal to Binary codes of the alphabet are presented

Operating Systems

Manage all computer resources; interface between software and hardware
Examples: DOS, Windows 11, Mac OS X, Unix, Linux, iOS, Android
Computer Hardware: Physical components (input/output devices)
Software: Programs running on the hardware; Moodle & LEA are online learning platforms.

Hardware Components

Box/Tower: Contains components in a cool, clean, and secure environment; prevents radio frequencies from spreading outside.
Motherboard: A printed circuit board serving as the computer’s foundation; allocates power, enabling communication between hardware.
Processor/CPU: Manages instructions from hardware and software using transistors to process data; examples include Intel Core i5-11600K.
System Clock/Internal Clock: Regulates instruction execution rates and synchronizes computer components.
RAM (Random Access Memory): Short-term data storage; contents are erased when the system is turned off.

Additional Hardware Components

Ports/Connectors: Connecting peripherals to the computer.
CMOS: Preserves hardware settings when the computer is off using a battery; stores system information and time.
Network Interface Card (NIC): Enables communication with other computers (e.g., radiology workstations).
Power Supply: Supplies electricity and cools the system.
Hard Disk Drive (HDD): Stores programs and data; uses moving parts; RAID is widely used in radiology systems for long-term archiving.
Solid State Drive (SSD): Stores data in microchips; faster than HDDs; suitable for both short-term and long-term storage in PACS.
Cloud Storage: Remote server-based storage accessible via the internet; useful for backing up data and files.
CD/DVD Disk Drives: Optical storage devices utilizing laser light to read and write data.
Input/Output Devices: Various input devices (e.g., mouse, keyboard), and output devices(e.g., monitor, speakers)

Computer Applications in Radiology

Computers control electronic devices (e.g., X-ray generators, control panels).
Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Ultrasound (US), and Nuclear Medicine (NM) are essential radiology applications.

Computer Networks

A telecommunications network enabling information exchange between computers.
Server: A computer providing services to other computers on the network, such as web servers, mail servers, and archive servers.
Thin Client: Hardware without a hard drive requiring continuous server interaction.
Thick Client (Fat Client): A workstation capable of functioning independently from the network.

Important Definitions

Network Classification (LAN, WAN, Intranet, Internet)
Network Protocols (e.g., TCP/IP)
Transmission of data in packets; used for information sharing on private networks (intranet or extranet) and the internet
OSI Model (Open Systems Interconnection) Model
IP Address: Unique address for each computer on a network
MAC Address: Unique physical address for hardware components
Gateway: Networking node connecting two separate networks with different transmission protocols
Hub and Switch: Network devices. A hub transmits every packet to all connected devices; a switch only transmits packets to the intended destination

Network Topologies

Patterns defining how computers and network devices are connected in a network
Star topology: Common in modern client-server networks with devices connecting to a central hub.
Other examples include bus, ring, and mesh (point-to-point) topologies.

Web-Based Systems

Client uses internet connection to access a network's web server to remotely access data (e.g., images in a PACS).
Advantage: Less powerful hardware required; potential for access from anywhere, faster retrieval
Disadvantages: Slower data download; often limited software functionality. Typically, images are saved as JPEG files only.

Internet and Intranet

Internet: An international network of networks using TCP/IP protocols.
Intranet: A local network using TCP/IP protocols for sharing information within an organization.

Telehealth and Telemedicine

Telehealth and telemedicine: Telecommunication applications providing community medical information and services (e.g., Info-Sante 811).
Telehealth: More broad, general, and may include prevention measures.
Telemedicine: Focuses on diagnosis and treatment.
Applications include diagnosis, education, research, phone and video conferencing, teleradiology, telepathology, and telesurgery

Teleradiology

Remote transmission of medical images for interpretation and/or consultation.
Accessed through various internet, WAN, LAN, satellite, and phone lines.
Increased use due to COVID-19.

RUISSS (Réseau Universitaire Intègre de la Santé et des Services Sociaux)

Coordinates tertiary healthcare services in remote areas of the province through associated teaching hospitals.
Supports healthcare professional training and development.
Tertiary Care: Specialized consultative care usually by referral from primary or secondary care personnel.

Network Security

Potential risks: Viruses; ethical issues, human errors, confidentiality issues; defective hardware/software; issues with data integrity and reliability (data loss, corruption).
Techniques to enhance security include anti-virus programs, anti-spyware software, firewalls, pop-up blockers, and encryption.

Calculating Image File Size and Storage Capacity

Image file size calculation formula: Matrix size x Bit Depth.
Calculations to determine the bytes of storage needed for digital image data based on a given matrix size and bit depth, along with calculations to determine how many images can be stored in a given storage space (e.g., 700MB or 1GB)
Image file size calculations shown for 2-D and 3-D datasets.

Raw Data & Image Data

Raw data: Unprocessed image data; acquired by the digital imaging unit.
Image data: Processed raw data, adjusted and without non-essential background data; typically, smaller size than raw data file.

Analog & Digital Signals

Analog signal: Continuous varying information (e.g., watch hands, analog X-ray film).
Digital signal: Discrete data units (e.g., digital watch, image acquisition systems such as CT, MRI, CR or DR).
Analog-to-digital converter (ADC): Translates analog signals into digital form.

Sampling and Quantization

Sampling: Specific points in time selected for conversion.
Quantization/Digitization: Analog level approximates to the closest digital level; assigned binary code.

Additional Information about Bit Depth

Bit depth method: Number of shades of gray in an image; e.g., 8 bits (256 shades); 16 bits (65,536 shades); 24 bits or more (many shades).

The Digital Image

Advantages: Image manipulation and reprocessing; lower storage and floor space requirements
Disadvantages: Lower spatial resolution compared to analog (film) images.

Image Matrix Sizes in Radiology

Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) have matrix dimensions from 256x256 up to 1024x1024.
Other imaging modalities like radioscopy, radiography, and mammography have different matrix sizes.

Calculation of Pixel Size

Pixel size calculation formula: Image area divided by matrix size.

Other Important Concepts

Exposure: Defined as the quantity of X-ray photons reaching the image receptor.
Factors affecting exposure: kVp, mAs, SID, SOD, OID, patient body habitus, part thickness, and other items.
kVp (Kilovoltage peak): Controls the energy of the X-ray beam, and thus its penetrating power; directly relates to exposure.
mAs (milliampere-seconds): Controls the quantity of X-rays generated; directly relates to exposure.
SID (Source to Image Distance): Controls exposure and magnification. Longer distance means less exposure.
SOD (Source to Object Distance): Controls exposure and magnification.
OID (Object to Image Distance): Affects magnification and shape distortion.
Inverse Square Law (ISL): Demonstrates the relationship between the distance from the source and exposure intensity.
Grid Ratio: The height of the lead strips in a grid divided by the distance between the strips; determines how a grid removes scatter.

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Description

This quiz covers the fundamental concepts of computer basics as they relate to image formation and management systems. Participants will learn about computer hardware components, network topologies, and the communication methods used in medical imaging. Additionally, it explores telehealth applications, data storage, and transmission requirements for PACS.