(78 days)
The ALI comPACS Data Compression Module for Diagnostic Images is an accessory to the ALI UltraPACS (K925965/A) Picture Archiving and Communication System. Through the use of JPEG and Motion JPEG lossy compression, ALI comPACS is intended to provide:
- significant reductions in the amount of electronic storage space for digitized diagnostic still images and digitized video of diagnostic images while maintaining medically acceptable diagnostic quality of the images; and
- significant reductions in the amount of time to transmit digitized diagnostic still images and digitized video of diagnostic images from storage to viewing sites, while maintaining medically acceptable diagnostic quality of the images.
The ALI comPACS Data Compression Module for Diagnostic Images is an accessory to the ALI UltraPACS (K925965/A) Picture Archiving and Communication System. ALI comPACS uses industry standard JPEG and Motion JPEG lossy compression for the compression of digitized diagnostic still images and digitized video of diagnostic images, respectively.
Here's an analysis of the provided text, extracting the requested information about acceptance criteria and the supporting study:
Acceptance Criteria and Device Performance
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Stated Goal) | Reported Device Performance |
|---|---|
| Significant reductions in storage space while maintaining medically acceptable diagnostic quality (Still Images) | Uses JPEG lossy compression (4:1 to 10:1 ratio) to achieve reductions while claiming "medically acceptable diagnostic quality" is maintained. No specific quantitative metric for "medically acceptable diagnostic quality" or statistical proof is provided. |
| Significant reductions in transmission time while maintaining medically acceptable diagnostic quality (Still Images) | Uses JPEG lossy compression (4:1 to 10:1 ratio) to achieve reductions while claiming "medically acceptable diagnostic quality" is maintained. No specific quantitative metric for "medically acceptable diagnostic quality" or statistical proof is provided. |
| Significant reductions in storage space while maintaining medically acceptable diagnostic quality (Video) | Uses Motion JPEG lossy compression (4:1 to 30:1 ratio) to achieve reductions while claiming "medically acceptable diagnostic quality" is maintained. No specific quantitative metric for "medically acceptable diagnostic quality" or statistical proof is provided. |
| Significant reductions in transmission time while maintaining medically acceptable diagnostic quality (Video) | Uses Motion JPEG lossy compression (4:1 to 30:1 ratio) to achieve reductions while claiming "medically acceptable diagnostic quality" is maintained. No specific quantitative metric for "medically acceptable diagnostic quality" or statistical proof is provided. |
| DICOM 3.0 Compliant (Still Images) | Yes |
| Compression level bounded | Yes (4:1 to 10:1 for JPEG, 4:1 to 30:1 for Motion JPEG) |
| Compatible with specific video signals (Composite Video, S-Video, NTSC, PAL) | Yes |
| Capture Rate (up to) | NTSC: 30 frames/second, 60 fields/second; PAL: 25 frames/second, 50 fields/second |
| Frame Dimensions (up to) | NTSC: 640x480; PAL: 768x576 |
| Colour Depth (YUV 4:2:2, 16.7 million colours) | Yes |
| Maximum Length of Captured Video | 120 seconds |
Note: The document explicitly states the primary goal is "maintaining medically acceptable diagnostic quality." However, it does not define what "medically acceptable diagnostic quality" means in terms of specific, quantifiable metrics (e.g., image quality scores, diagnostic accuracy, detection rates). It only describes the mechanism (lossy compression) and the ranges applied. Therefore, the "reported device performance" in the table above refers to the claims and features related to achieving this goal, rather than documented quantitative results against defined acceptance criteria.
Study Information
The provided document describes the device and its intended use, as well as a comparison to a substantially equivalent device. However, it does not describe a clinical study or performance testing that proves the device meets the "medically acceptable diagnostic quality" claim. The document relies on the following for demonstrating efficacy:
- Substantial Equivalence: The core argument for safety and effectiveness is based on substantial equivalence to the CEMAX-ICON Archive Manager 2.0 and Autorad modules (K955092). The document meticulously compares the features of ALI comPACS to the predicate device, highlighting similarities and distinguishing features (primarily the Motion JPEG capability for video).
- Industry Standard Technology: It highlights that ALI comPACS uses "industry standard JPEG and Motion JPEG lossy compression." It asserts that "Motion JPEG is an intraframe JPEG compression format... which is essentially a storage format for sequential JPEG compressed images presented at a chosen frame rate. Thus Motion JPEG compression does not raise any additional issues of safety or effectiveness beyond those already addressed by JPEG compression itself." This implies that because JPEG is a recognized standard, its application here is inherently acceptable, and Motion JPEG, being based on JPEG, carries the same assumed safety and effectiveness.
- User Control and Preference: The document states, "The clinical operator selects the compression ratio based on medical preference of two images/videos, one the original image/video and the second the image/video compressed to the desired lossy compression ratio." This places the onus of determining "medically acceptable diagnostic quality" on the clinical operator's judgment at the point of use, rather than through a pre-defined validation study.
Given this, the following sections cannot be fully answered as no such study is described in the provided text.
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Not applicable. No specific performance study with a test set generating new data is described. The document relies on substantial equivalence and the inherent nature of JPEG and Motion JPEG compression.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not applicable. No specific performance study with a test set subject to expert review is described. The document references "medical preference" by a "clinical operator" when selecting compression ratios, but this is not part of a formal ground truth establishment process for a validation study.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable. No formal test set and ground truth adjudication is described.
5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
- Not applicable. This device is a data compression module, not an AI diagnostic assistant. Thus, an MRMC study comparing human readers with and without AI assistance is not relevant to its function and was not performed.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. While the algorithm operates standalone in compressing data, no standalone performance study (e.g., quantitative image quality metrics, diagnostic accuracy without human review of compressed images vs. original) is described in the provided text. The device's efficacy is tied to the concept of "medically acceptable diagnostic quality" as judged by a human operator.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- Implicit based on "medical preference" by clinical operators. For the operation of the device, the ground truth for "medically acceptable diagnostic quality" is established by the clinical operator visually comparing original and compressed images to their "medical preference." For the regulatory claim, the ground truth is implicitly derived from the acceptance of JPEG compression as an industry standard and the substantial equivalence to a predicate device. No formal external ground truth (e.g., pathology, long-term outcomes, expert consensus on a standardized dataset) is described as being used to validate the device itself.
8. The sample size for the training set
- Not applicable. This device is a rule-based compression algorithm (JPEG/Motion JPEG); it does not employ machine learning or require a training set in the conventional sense.
9. How the ground truth for the training set was established
- Not applicable. As above, no training set or machine learning components are described for this device.
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Summary of Safety and Effectiveness for ALI comPACS Data Compression Module for Diagnostic Images
8.1 Demographic Information
NOV 27 1996
8.1.1 Date Prepared
September 9, 1996
8.1.2 Submitter
A.L.I. Technologies Inc. 95-10551 Shellbridge Way Richmond, B.C. Canada, V6X 2W9 Tel: 604-279-5422 Fax: 604-279-5468
8.1.3 Contact
Robert MacNeil P.Eng. Manager, Quality Assurance and Regulatory Affairs
8.2 Device Name
8.2.1 Trade or Proprietary Name
ALI comPACS Data Compression Module for Diagnostic Images
8.2.2 Common Name
ALI comPACS Data Compression Module for Diagnostic Images
8.2.3 Classification Name
There is no official FDA classification name for this accessory. The common name used by FDA for these devices is Picture Archiving and Communications Systems.
8.3 Devices to which Substantial Equivalence is being Claimed
CEMAX-ICON Archive Manager 2.0 and Autorad modules (K955092).
8.4 Device Description
8.4.1 Function
The ALI comPACS Data Compression Module for Diagnostic Images is an accessory to the ALI UltraPACS (K925965/A) Picture Archiving and Communication System.
ALI comPACS operates as follows:
- The clinical operator selects the functions where lossy compression is to be applied 1. (archiving, viewing, transmitting, still images, videos) .
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- The clinical operator selects the compression ratio based on medical preference of two images/videos, one the original image/video and the second the image/video compressed to the desired lossy compression ratio.
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- The clinical operator proceeds with use of ALI UltraPACS. Images/videos that have been lossy compressed have the characters "LOSSY xx:1" (where xx is the compression ratio) placed in the visible, non-diagnostic area of the image or video.
8.4.2 Scientific Concept
ALI comPACS uses industry standard JPEG and Motion JPEG lossy compression for the compression of digitized diagnostic still images and digitized video of diagnostic images, respectively. The scientific concept of JPEG compression is defined in the ISO //EC standard ISO/IEC 10918-1 Digital Compression and Coding of Continuous Tone Still Images. Motion JPEG is a file format for the storage of sequentially JPEG compressed frames of video.
8.4.3 Significant Physical and Performance Characteristics
| Compression Method | JPEG Lossy Compression |
|---|---|
| Compression Ratio Range | 4:1 up to 10:1 |
| Original Diagnostic ImageSize (pixels and depth) | Greyscale640 horizontal x 480 vertical (NTSC), 256 levels (8 bit)768 horizontal x 576 vertical (PAL), 256 levels (8 bit)Colour640 horizontal x 480 vertical (NTSC), 16.7 million colours (24 bit)768 horizontal x 576 vertical (PAL), 16.7 million colours (24 bit) |
| DICOM 3.0 Compliant | Yes |
| Functions where Compressioncan be applied | Archiving, Viewing, Transmitting |
For compression of digitized diagnostic still images
For compression of digitized video of diagnostic images
| Compression Method | Motion JPEG Lossy Compression |
|---|---|
| Compression Ratio Range | 4:1 up to 30:1 |
| Compatible Video Signals | Composite Video, S-Video, NTSC, PAL |
| Capture Rate | Up to 30 frames/second (NTSC),25 frames/second (PAL).Up to 60 fields/second (NTSC),50 fields/second (PAL). |
| Frame Dimensions (in pixels) | Up to 640 horizontal x 480 vertical (NTSC),Up to 768 horizontal x 576 vertical (PAL) |
| Colour Depth | YUV 4:2:2, 16.7 million colours (24 bit colour) |
| Maximum Length of Captured Video | 120 seconds |
| Functions where Compression can be applied | Archiving, Viewing, Transmitting |
8.5 Statement of Intended Use
The ALI comPACS Data Compression Module for Diagnostic Images is an accessory to the ALI UltraPACS (K925965/A) Picture Archiving and Communication System. Through the use of JPEG and Motion JPEG lossy compression, ALI comPACS is intended to provide:
-
- significant reductions in the amount of electronic storage space for digitized diagnostic still images and digitized video of diagnostic images while maintaining medically acceptable diagnostic quality of the images; and
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- significant reductions in the amount of time to transmit digitized diagnostic still images and digitized video of diagnostic images from storage to viewing sites, while maintaining medically acceptable diagnostic quality of the images.
8.6 Comparison of Technological Characteristics
The ALI comPACS Data Compression Module for Diagnostic Images is substantially equivalent to the CEMAX-ICON Archive Manager 2.0 and Autorad modules (K955092). Archive Manager 2.0 and Autorad, with its related Telemax software module (for viewing images under Windows 95 or MAC) and Imagecom software modules (for image transmission) use JPEG compression for viewing. transmitting, and archiving images using lossy compression.
| Feature | ALI comPACS | CEMAX-ICONproduct |
|---|---|---|
| Uses JPEG lossy compression in viewing images | Yes | Yes (Autorad,Telemax) |
| Uses JPEG lossy compression in transmittingimages | Yes | Yes (Imagecom) |
| Uses JPEG lossy compression for archivingimages | Yes | Yes (ArchiveManager 2.0) |
| Uses Motion JPEG for viewing digital video ofmedical images | Yes | No (limited to stillframe images) |
| Uses Motion JPEG for transmitting digital video ofmedical images | Yes | No (limited to stillframe images) |
| Uses Motion JPEG for archiving digital video ofmedical images | Yes | No (limited to stillframe images) |
| Compression level bounded | Yes | Yes (fixed value) |
| DICOM 3.0 compliant for still images (DICOMdoes not yet address digital video) | Yes | Yes |
The major difference between ALI comPACS and the CEMAX-ICON products Archive Manager 2.0 and Autorad is that ALI comPACS provides viewing, transmission, and archiving of lossy compressed digital video. ALI comPACS uses Motion JPEG for compressing the digital video of the diagnostic images. Motion JPEG is an intraframe JPEG compression format (i.e. JPEG applied to each frame, then each frame is stored), which is essentially a storage format for sequential JPEG compressed images presented at a chosen frame rate. Thus Motion JPEG compression does not raise any additional issues of safety or effectiveness beyond those already addressed by JPEG compression itself.
In conclusion, ALI comPACS is substantially equivalent to the CEMAX-ICON products Archive Manager 2.0 and Autorad.
§ 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).