(437 days)
RealNow is an image processing software package to be used by trained professionals including physicians. The software runs on a standard "off-the-shelt" computer or a virtual platform, such as VMware, and can be used to perform image viewing, processing, analysis and communication of computed tomography (CT) perfusion scans of the brain. Data and images are acquired through DICOM compliant imaging devices.
RealNow provides viewing, analysis and communication capabilities for functional and dynamic imaging datasets that are acquired with CT Perfusion imaging protocols.
Analysis includes calculation of parameters related to tissue flow (perfusion) and tissue blood volume. Results of image processing which include CT perfusion parameter maps generated in the standard DICOM format and may be viewed on existing radiological imaging viewers.
RealNow image analysis includes calculation of the following perfusion related parameters:
- Cerebral Blood Flow (CBF)
- Cerebral Blood Volume (CBV)
- Mean Transit Time (MTT)
- Residue function time-to-peak (TMax)
- Arterial Input Function (AIF)
The primary users of RealNow are medical imaging professionals who analyze dynamic CT perfusion studies. The results of image analysis produced by RealNow should be viewed through appropriate diagnostic viewers when used in clinical decision making.
The RealNow device is an image processing software package for CT perfusion scans of the brain. The acceptance criteria and the study proving the device meets these criteria are detailed below. The study's "ground truth" for non-clinical testing was the output of a legally marketed predicate device, RAPID (K121447).
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for RealNow were established by comparing its output to the RAPID predicate device. The performance was assessed through pixel-by-pixel comparison and volumetric analysis.
| Acceptance Criterion (for each scan) | Reported Device Performance |
|---|---|
| Intraclass Correlation Coefficient (ICC) > 0.75 for all voxels within the brain tissue for parametric maps. | CBF, CBV, MTT, Tmax Parameter Maps: All proportion of acceptable maps (ICC > 0.75) were > 90% (p=0.0009 for CBF and CBV, p=0.0196 for MTT and Tmax). Specific ICC values are not provided, only the proportion of maps meeting the threshold. |
| Assessment of bias for volumetric comparison (e.g., CBF |
§ 892.2050 Medical image management and processing system.
(a)
Identification. A medical image management and processing system is a device that provides one or more capabilities relating to the review and digital processing of medical images for the purposes of interpretation by a trained practitioner of disease detection, diagnosis, or patient management. The software components may provide advanced or complex image processing functions for image manipulation, enhancement, or quantification that are intended for use in the interpretation and analysis of medical images. Advanced image manipulation functions may include image segmentation, multimodality image registration, or 3D visualization. Complex quantitative functions may include semi-automated measurements or time-series measurements.(b)
Classification. Class II (special controls; voluntary standards—Digital Imaging and Communications in Medicine (DICOM) Std., Joint Photographic Experts Group (JPEG) Std., Society of Motion Picture and Television Engineers (SMPTE) Test Pattern).