Informatics in Medical Imaging: Key Concepts and Standards

What is biomedical informatics (BMI)?

A broad, interdisciplinary field involving platforms used for medical purposes such as patient care and clinical research.

What does biomedical informatics study?

The use of data, information, and knowledge to improve human health.

How does biomedical informatics differ from health informatics?

Biomedical informatics is the broader field, while health informatics is a subset focused on using health information to improve care, administration, and public health.

What areas are included within health informatics?

Clinical, consumer, administrative, and imaging informatics.

Are the terms biomedical informatics and health informatics sometimes used interchangeably?

Yes. The terms are often used interchangeably in the literature.

What is clinical informatics?

A subspecialty of informatics that uses data and information technology to deliver clinical healthcare services.

What is imaging informatics?

A subspecialty of clinical informatics specific to radiology.

What does PACS stand for?

Picture Archiving and Communication System.

What is PACS?

A networked group of computers, servers, and archives used to store, retrieve, distribute, and manage digital medical images.

What new term does the FDA use to describe PACS?

Medical Image Management and Processing Systems (MIMPS).

What does HIS stand for?

Hospital Information System.

What is a Hospital Information System (HIS)?

A database containing all patient medical record information.

What does RIS stand for?

Radiology Information System.

What is a Radiology Information System (RIS)?

A radiology-specific database.

What have HIS and RIS increasingly been merged into?

The Electronic Health Record (EHR).

What is an Electronic Health Record (EHR)?

A comprehensive electronic version of an individual patient's collection of medical documents.

What is an example of an EHR system?

Epic.

What are important characteristics of an EHR?

It can include a patient portal, securely share a seamless stream of patient information among healthcare entities, and integrate with PACS, HIS, and RIS.

How were PACS, HIS, and RIS often accessed before comprehensive EHR integration?

Different applications were often used to access each system.

What does DICOM stand for?

Digital Imaging and Communications in Medicine.

What is DICOM?

The worldwide standard format for communicating imaging files.

When did DICOM originate?

1983.

What file extension does DICOM use?

.dcm

What are the two parts of a DICOM file?

The DICOM header and image data.

What is the DICOM header similar to?

Metadata attached to a photo, which stores information about the image.

What information is recorded in the DICOM header?

Demographic and image-capture information for every DICOM image.

What are examples of information found in a DICOM header?

Patient name, birthdate, institution, image dimensions, modality, slice thickness, and Exposure Indicator.

What does the image-data portion of a DICOM file contain?

Pixel values.

What two classes of information does DICOM use?

Object and Service.

What does the DICOM Object class contain?

Information about the study and patient.

What does the DICOM Service class describe?

What to do with the object.

What is formed when DICOM Object and Service classes are combined?

Service/Object Pairs (SOPs).

What does HIPAA stand for?

Health Insurance Portability and Accountability Act.

When was HIPAA enacted?

1996.

What does HIPAA require regarding medical information?

Medical information must be protected from unauthorized usage and access.

What does HL-7 provide?

A standard for communicating and exchanging information between medical applications.

What is the purpose of a network in medical imaging?

To allow images to be transferred within and outside the imaging site.

Why is a wired network connection preferred over wireless for DICOM studies?

DICOM studies can be large.

In what units are file sizes measured?

Bytes, including kilobytes, megabytes, gigabytes, and terabytes.

How many bytes are in 1 kilobyte according to the notes?

1,000 bytes.

How many kilobytes are in 1 megabyte according to the notes?

1,000 kilobytes.

How many megabytes are in 1 gigabyte according to the notes?

1,000 megabytes.

What is the typical grayscale bit depth of diagnostic x-ray images?

Approximately 10 to 16 bits.

How many bits are in 1 byte?

8 bits.

What is the formula for calculating image file size?

Image file size = XY(B/8).

In the image file-size formula, what does X represent?

The x-axis pixel matrix size.

In the image file-size formula, what does Y represent?

The y-axis pixel matrix size.

In the image file-size formula, what does B represent?

Bit depth.

What is the file size of a 2000 × 2000 image with a 12-bit depth?

6,000,000 bytes, or 6,000 kilobytes, or 6 megabytes.

What is a printed film image called?

Hard copy.

What is an image viewed on a monitor called?

Soft copy.

What type of monitors are usually used in radiology?

LCD (Liquid Crystal Display) flat screens.

Why is ambient lighting kept low in a radiology reading room?

Monitor maximum luminance is relatively low, so low ambient lighting helps images be viewed appropriately.

Can a monitor's brightness and contrast be individually adjusted?

Yes.

Are monitor brightness and contrast adjustments the same as brightness and contrast processing applied to an image?

No. They are entirely separate processes.

Why must radiologists' monitors have high resolution?

To aid in diagnosis.

Can monitors used by technologists and other physicians have lower resolution than radiologists' monitors?

Yes, because they are not making the diagnosis.

What does a laser film printer produce?

A latent-image hard copy on laser film.

What is short-term image storage?

Storage that may be on the local hard drive of the imaging system before the image is sent to PACS.

What is long-term image storage?

PACS/MIMPS storage.

What feature of long-term PACS/MIMPS storage helps prevent data loss if a hard drive fails?

Built-in data redundancy backup.

What is off-site storage?

Storage at a different physical location.

Why is off-site storage used?

To ensure data integrity in case of a catastrophic event at an institution.

Why is understanding clinical informatics workflow important?

It helps technologists understand how information and imaging processes move through the clinical radiology environment.

How can a student begin to understand radiology workflow?

By spending time in radiology in a clinical setting.

What does CPOE stand for?

Computerized Provider Order Entry.

What is CPOE?

The process by which providers enter orders.

What does CDS stand for?

Clinical Decision Support.

What is Clinical Decision Support (CDS)?

A developing field intended to create systems within the EHR that assist providers in making the correct clinical decision.

What is an example of CDS in radiology?

The EHR can provide hints or suggestions to help a provider choose the correct imaging order based on the patient's symptoms.