(60 days)
The intended use for DownScan 120 is conversion of X-ray (stationary, C-arm, angiography, etc.), nuclear medicine, magnetic resonance, and ultrasound images either directly from their source, or from an intermediate storage device (like a video tape or video disk), for use on display monitors, optical, tape or disk recorders, or other apparatus requiring a standard frame rate video signal (30 or 25 frames/second). The use of DownScan 120 is indicated whenever the source and destination of a video signal are incompatible due to different line and/or frame rates, and a standard frame rate video signal is required. DownScan 120 is intended for use in patient care areas, but is not intended to have any patient contact.
DownScan 120 is a digital image processing system that can convert from very-high-line rate video standard of 1023-1049/60 or 1249/50 (~64 KHz horizontal frequency, often referred to as "flicker free" or "fast" video) to high-line rate video standards of 1023-1049/30 or 1249/25, or to low-line rate video standards of 525/30 or 625/25. Housed in a 1 3/4" EIA rack mount chassis, DownScan 120 operates from 100V to 240V AC power.
DownScan 120 consists of an enclosed sheet metal chassis housing one main printed wiring assembly, one secondary printed wiring assembly, and the power supply (100-240 VAC input and ±15 VDC, ±5 VDC outputs). DownScan 120 uses standard SSI/MSI/LSI semiconductor technology.
DownScan 120 utilizes eight basic electronic circuits on the primary printed wiring assembly. They are: input analog video conditioning circuit, analog-to-digital conversion circuit, memory circuits, various control circuits, digital-to-analog conversion circuit, two clock circuits, and output analog video conditioning circuit.
All of the processing is done in the digital domain. The analog-to-digital converter changes the analog video to an 8-bit digital bus. That digital bus is sent to the memories for processing. Memory control circuits manage the locations and the timing of how the video is being stored in the memories and then read from memory before sending the resultant signal to the 8-bit digital-to-analog circuit.
The write clock generator provides clock timing for analog-to-digital conversion, the memories and the memory control circuits. The read clock generator provides read clock timing for the memories and the digital-to-analog circuits.
This document describes the DownScan 120, a digital image processing system that converts specialized video signals (e.g., from X-ray) to standard video formats. The submission focuses on demonstrating substantial equivalence to a predicate device, the UniScan.
Here's an analysis of the provided information, framed by your requested criteria:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly defined by compliance with industry standards and maintenance of image quality. The performance data is largely a statement of compliance and capability rather than specific metrics in a typical sense for a diagnostic device.
| Acceptance Criterion (Implicit) | Reported Device Performance (DownScan 120) |
|---|---|
| Video Signal Conversion (Functionality) | Converts from high-line rate video (1023-1049/60 or 1249/50) to high-line rate (1023-1049/30 or 1249/25) or low-line rate (525/30 or 625/25) video standards. |
| Compliance with Video Standards | Meets appropriate requirements of RS-170 and RS-343A. |
| Aspect Ratio Compensation | Correctly compensates for aspect ratio changes (tested in accordance with SMPTE RP-133). |
| Low-Contrast Imaging Resolution | Permits low-contrast imaging resolution at the 1% level (tested in accordance with SMPTE RP-133). |
| Electrical Compatibility | Electrically compatible with industry standard monochrome video signals. |
| Image Quality Preservation | Image quality is preserved (within the limits of standard video technology). |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not explicitly stated in terms of 'cases' or 'patient data'. The testing described is a functional and technical validation of the device's video processing capabilities against established standards. It's not a study involving a "test set" of medical images in the way one would evaluate an AI diagnostic tool.
- Data Provenance: Not applicable in the context of diagnostic data. The "data" here refers to the output of the device itself when processing various video signals, and its compliance with technical specifications.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Experts
- Number of Experts: Not applicable. The ground truth for this device's performance is compliance with engineering standards (RS-170, RS-343A, SMPTE RP-133) and the inherent functioning of its electronic circuits.
- Qualifications of Experts: Not applicable. Device testing against standards typically involves engineers and technical staff.
4. Adjudication Method for the Test Set
- Adjudication Method: Not applicable. Testing against technical standards does not involve human adjudication in the same way clinical diagnostic accuracy studies do. Performance is assessed by direct measurement against defined technical parameters.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size
- MRMC Study: No. This device is a video signal converter, not a diagnostic algorithm that assists human readers. Its purpose is to present images, not interpret them.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Study Was Done
- Standalone Study: Yes, in a sense. The described tests are "standalone" in that they evaluate the device's technical performance metrics (e.g., meeting RS-170, RS-343A, SMPTE RP-133) independent of a human operator's diagnostic interpretation. The device's primary function is a technical one (video conversion), not a diagnostic one.
7. The Type of Ground Truth Used
- Type of Ground Truth: Technical specifications and industry standards (RS-170, RS-343A, SMPTE RP-133). The "ground truth" is that the device should accurately convert video signals and maintain image quality as defined by these engineering benchmarks.
8. The Sample Size for the Training Set
- Sample Size: Not applicable. This is a hardware device with embedded firmware, not an AI/ML algorithm that undergoes a "training" phase with a dataset.
9. How the Ground Truth for the Training Set Was Established
- Ground Truth Establishment: Not applicable, as there is no training set in the context of AI/ML. The device's design and functionality are based on established electrical engineering principles and standards.
§ 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).