The US Food and Drug Administration (FDA) released a new draft guidance intended to clarify the information device makers should include in their 510(k) submissions for displays used in diagnostic radiology.
These devices are used to display, store, transfer or process medical images and are commonly used by radiologists to make diagnoses. Display devices are systems that use liquid crystal display (LCD) and light-emitting diode (LED) technology to display images in combination with communication and storage hardware and software to enhance and analyze the images.
The new draft guidance, Display Devices for Diagnostic Radiology, provides manufacturers with the information needed in a 510(k) submission and clarifies expectations between display devices used for mammography and displays that are not intended to be used for mammography.
The draft guidance will replace a 2008 guidance, Display Accessories for Full-Field Digital Mammography Systems – Premarket Notification (510(k)) Submissions, when finalized.
In the guidance, FDA says sponsors should clearly state whether a device is or is not intended for mammography. For devices not intended for mammography, FDA recommends including a disclaimer in the Indications for Use (IFU) statement specifying that the device is not intended for mammography.
To establish substantial equivalence with an existing device, FDA says sponsors should discuss "any differences in the technological characteristics between [their] device and the predicate device." The specific characteristics that should be discussed are listed in Table 1.
|Table 1. Technical Characteristics of Display Devices|
Backlight type (transmissive displays only)
Frame rate and refresh rate
Pixel array, pitch, subpixel pattern, pixel aperture ratio
Subpixel driving (spatial and temporal dithering)
Ambient light sensing
Luminance calibration tools
For software and firmware, FDA says sponsors should include documentation of all software and firmware used in the device based on "level of concern." FDA says it considers software and firmware used for display controls, ambient light sensing, luminance calibration, and quality-control to be of minor concern. For other types of software and firmware, the agency says sponsors should ask how it should be classified.
The guidance also offers a breakdown of what types of performance testing FDA recommends for non-mammography and mammography device submissions. Some measurements, such as spatial resolution and pixel defects should be tested for either type of device, while others are only recommended for devices with a mammography indication.
Labeling and User Manuals
For device labeling, FDA says sponsors should include "clear and concise instructions for use that delineate the technological features of [the] device and how [the] device is to be used."
The agency also says the device labeling should encourage "local/institutional training programs" to ensure users know how to properly operate the displays.
For devices used for mammography, the label should include a disclaimer that states:
"Mammographic images with lossy compression must not be reviewed for primary image interpretations. Mammographic images may only be interpreted using an FDA cleared display that meets technical specifications reviewed and accepted by FDA."
Additionally, FDA says the user manual for display devices should include information on who is authorized to use the device, maintenance, calibration and quality assurance, as well as:
- The Indications for Use as stated in your premarket submission;
- Warnings and precautions (and any mitigation measures);
- Overview of the device;
- Principles of operation;
- Directions for use (e.g., display controls and GUI);
- Technical specifications;
- Performance specifications (summary of physical laboratory testing);
- Cleaning information;
- Hardware/software compatibility requirements;
- Conformity to any voluntary standards; and
- Manufacturer's contact information.