Noninterpretive Skills: Imaging Informatics Part 1
Part 1 review of Noninterpretive Skills: Imaging Informatics for radiology board review. Download the free study guide on this topic by clicking here.
Show Notes/Study Guide:
Please refer to the most current version of the American Board of Radiology Noninterpretive Study Guide, available for download from the ABR, to assure accuracy of the information discussed. The 2024 version of the ABR NIS study guide is currently available at: https://www.theabr.org/wp-content/uploads/2024/01/2024-NIS-Study-Guide.pdf
What is the DICOM standard, and what are its primary functions in medical imaging?
The Digital Imaging and Communications in Medicine (DICOM) standard is an international protocol used for the display, transfer, storage, and processing of medical images. It encompasses both pixel-based image data and metadata, which are stored in the DICOM header of each image. DICOM enables organized querying, retrieval, and transmission of data between systems, and facilitates the transmission of order information between the radiology information system (RIS) and imaging modalities (e.g., CT, MR, or ultrasound machines), reducing the risk of data entry errors. Vendors must provide conformance statements to ensure interoperability when implementing DICOM.
What type of the information is contained in the DICOM header?
The DICOM header contains details about the image, series, exam, patient name, imaging facility at which the imaging was performed, and the type or model of scanner. More specifically, the DICOM header contains metadata about the medical image. This metadata includes:
-Patient Information: name, patient ID, date of birth, and gender.
-Study information: study date and time, study description, referring physician’s name
-Series information: series number, series description, modality (e.g., CT, MR, ultrasound)
-Image information: image number, image type, acquisition date and time
-Scanner information: manufacturer, scanner model, device setting information
-Facility information: Name of imaging facility, location
This organized structure allows for efficient querying, retrieval, and transmission of medical imaging data between different systems.
What is HL7, how does the HL7 standard facilitate the exchange of medical information, and what are its main versions?
HL7 (Health Level Seven) is an international standards organization responsible for developing standards for the exchange, integration, sharing, and retrieval of medical information, excluding image data. The HL7 V2 messaging standard is the most widely used healthcare-related standard worldwide, enabling interoperability between different electronic medical systems. Although HL7 V3 is more human-readable, it is less commonly adopted due to its complexity. The HL7 Fast Healthcare Interoperability Resources (FHIR®) standard is a newer protocol that allows the use of internet transactions to exchange medical data between systems, enhancing the potential for seamless data exchange.
What is RadLex, and what is its significance in radiology?
RadLex is the largest radiology-specific lexicon, and contains 68,000 terms pertaining to imaging anatomy, procedures, and pathology. It is as an ontology, meaning it organizes terms and their relationships. The RadLex Playbook standardizes imaging exam names, descriptions, and codes. This Playbook merged with LOINC (Logical Observation Identifiers Names and Codes), the international standard for health measurements and documents, enhancing the standardization and interoperability of radiological data in medical systems.
What is a PACS system, and how does PACS support radiologists in medical imaging?
PACS, standing for Picture Archiving and Communication System, serves as the primary tool for radiologists for image viewing and interpretation. It consists of essential components such as displays, workstations, short-term storage, and long-term archiving systems. PACS interfaces with imaging modalities through DICOM transactions and communicates with Radiology Information Systems (RIS) and/or Electronic Medical Records (EMR) using HL7 transactions, which are translated to and from DICOM. Unlike early versions that required dedicated physical workstations, modern PACS systems are web-based and accessed by mobile devices and desktop thin clients, enhancing flexibility and accessibility for radiologists.
What is the vendor-neutral archive (VNA)?
The vendor-neutral archive (VNA) allows for centralized storage of data supporting various DICOM image types and non-DICOM data like photographs and pathology slides. Enterprise imaging utilizes VNA technology extensively to streamline the sharing, viewing, and storage of medical imaging data across various departments beyond radiology. However, a significant challenge lies in standardizing the formatting and exchange of metadata (e.g., patient and imaging details, acquisition date) accompanying non-DICOM images within enterprise imaging systems.’
What does RIS stand for, and what does this do?
The Radiology Information System (RIS) is software that manages imaging exams, order reconciliation, scheduling, communication with various scanners and PACS, reporting, results notification, and billing. It can operate independently or integrate as part of the Electronic Medical Record (EMR).
What are key factors of the ACR-AAPM-SIIM technical standards for reading room lighting and diagnostic monitor luminance?
The ACR-AAPM-SIIM technical standard suggests that optimal ambient lighting in a reading room should range between 25 to 50 lux, which is like standing under a streetlight at night in dark conditions. For diagnostic monitors, the standard recommends a minimum gray value luminance of 350 cd/m2 for nonmammographic interpretation and 420 cd/m2 for mammographic interpretation.
What is the difference between lossless and lossy image compression for image storage?
Image compression is used to lower the storage requirements of radiology images. Lossless compression removes portions of the image which are redundant and not important for medical imaging interpretation such as the black background on a CT image. Lossless compression currently allows image file size to be reduced by about 3 to 1. Lossy compression removes redundant as well as minimally important image information with the goal to preserve as much diagnostic quality as possible. Lossy compression can lower image file size by about 10 to 1.
What are 3 classic repetitive strain injuries radiologists are susceptible to due to work conditions?
Due to many hours at a computer workstation, radiologists are prone to repetitive strain injuries (RSIs). Three classic repetitive strain injuries radiologists are prone to are carpal tunnel syndrome (involving median nerve), cubital tunnel syndrome (involving ulnar nerve) and DeQuervain tenosynovitis (thumb). To minimize the risk of repetitive strain injury, proper workstation ergonomics should be assured.
What are key workflow steps from imaging order to issuing the imaging report?
1. Order placed in electronic medical record.
2. HL7 transactions communicate the order to RIS.
3. RIS communicates the order to the scanner via the DICOM Modality Work List and the image is obtained.
4. The scanner communicates with PACS via DICOM transactions to transfer the image.
5. A radiologist views the image on PACS and dictates a report, typically with voice recognition software.
6. The reporting software sends the report to RIS and the electronic medical record, again using HL7 transactions.
What is the difference between disaster recovery and business continuity procedures?
Disaster recovery and business continuity procedures are both part of the downtime procedures of a radiology workflow. Disaster recovery procedures come into play, as the name suggests, in the event of a disaster, and become particularly useful in highly disruptive disasters. Disaster recovery procedures include establishing in advance of a disaster how off-site data backup systems will be managed, including how often data will be backed up, and the steps necessary to restore critical data if a disaster or other disruption occurs.
On the other hand, business continuity procedures are those procedures necessary to continue to care for patients when a system failure occurs under non-disastrous circumstances, such as a routine power outage. Business continuation procedures also specify policies to follow including backup requirements so there often will be some overlap between disaster recovery and business continuity procedures.
What does it mean that radiology systems need to be so-called “high-availability (HA) systems”?
High-availability systems must be able to withstand service disruptions by having in place automated recovery and failover operations if a service disruption occurs. There is a so-called “number of nines” expectation for high-availability systems, and for radiology the ABR states that PACS, for example, is expected to achieve “four nines” of uptime meaning it is functional 99.99% of the time. Interestingly, per the ABR, this means that PACS should have no more than 50 minutes of downtime a year. To achieve this level of reliability, the system needs high fault tolerance, meaning functionality will continue if single components of the system fail. This requires redundancy within the system components such as redundancy in servers, storage archives, and network connections.
