(56 days)
The GM85 Digital Mobile X-ray imaging System is intended for use in generating radiographic images of human anatomy by a qualified/trained doctor or technician. This device is not intended for mammographic applications.
The GM85 Digital Mobile X-ray Imaging System is used to capture images by transmitting X-ray to a patient's body. The X-ray passing through a patient's body is sent to the detector and then converted into electrical signals. These signals go through the process of amplification and digital data conversion in the signal process on the S-Station, which is the Operation Software (OS) of Samsung Digital Diagnostic X-ray System, and save in DICOM file, a standard for medical imaging. The captured images are tuned up by an Image Post-processing Engine (IPE) which is exclusively installed in S-Station, and send to the Picture Archiving & Communication System (PACS) sever for reading images.
The provided text describes a 510(k) premarket notification for the GM85 Digital Mobile X-ray Imaging System. The primary purpose of this notification is to add a new detector configuration to an already cleared device (K220175). As such, the study described focuses on demonstrating the substantial equivalence of the new detector and its integration, rather than establishing primary performance metrics from scratch for a completely new device.
Here's a breakdown of the acceptance criteria and the study conducted based on the provided information:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly tied to demonstrating equivalence to the predicate device's existing performance, particularly for the new detector. The non-clinical and clinical (phantom image evaluation) data serve to show that the new detector maintains similar performance characteristics.
| Acceptance Criteria Category | Specific Metric (Implicit/Explicit) | Predicate Device Performance | Proposed Device (New Detector) Performance | Discussion/Acceptance |
|---|---|---|---|---|
| Durability | N/A (General statement) | Assumed to be met | Retains same durability | Met |
| Functionality | N/A (General statement) | Assumed to be met | Retains same functionality | Met |
| Operation | N/A (General statement) | Assumed to be met | Retains same operation | Met |
| Detector Type | Detector Type | Csl, Indirect | Csl, Indirect | Same (Met) |
| Detector Area | Detector Area | 14"X17" (345mmX425mm) | 14"X17" (345mmX425mm) | Same (Met) |
| Number of Pixels | Number of Pixels | 2466X3040 | 2466X3040 | Same (Met) |
| Pixel Pitch | Pixel Pitch | 140 um | 140 um | Same (Met) |
| High Contrast Limiting Resolution | High Contrast Limiting Resolution | 3.57 LP/mm | 3.57 LP/mm | Same (Met) |
| Communication | Communication | Wired / Wireless | Wired / Wireless | Same (Met) |
| Dust/Water-resistance | Dust/Water-resistance Rating | IP54 | IP54 | Same (Met) |
| Max. Load Capacity | Max. Load Capacity | 400 kg/200 kg | 400 kg/200 kg | Same (Met) |
| DQE | DQE (0lp/mm, Typical) | 76% | 76% | Same (Met) |
| MTF | MTF (0.5lp/mm, Typical) | 86% | 86% | Same (Met) |
| Weight | Weight (w/o Battery Set) | Approx. 2.76 kg | Approx. 2 kg | Difference acknowledged as not impacting safety/effectiveness |
| Image Quality Evaluation | Average Score of Image Quality | Baseline (predicate) | Equivalent to predicate devices | Found to be equivalent (Met) |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: The document mentions "Anthropomorphic phantom images were provided." It does not specify the exact number of phantom images or the number of distinct phantom cases used in the evaluation.
- Data Provenance: The nature of phantom images means the data is synthetic/simulated clinical data (using phantoms to mimic human anatomy) rather than human patient data. The country of origin for the data is not explicitly stated, but it would have been generated as part of the manufacturer's internal testing as advised by FDA guidance. The study is prospective in the sense that the evaluations were specifically conducted for this submission.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Number of Experts: The document states that phantom images "were evaluated by professional radiologists." It does not specify the exact number of radiologists involved.
- Qualifications of Experts: They are described as "professional radiologists." Specific lengths of experience or subspecialties are not provided.
4. Adjudication Method for the Test Set
- The document implies a consensus or comparison approach: "They were evaluated by professional radiologists and found to be equivalent to the predicate devices. There is no significant difference in the average score of image quality evaluation between the proposed device and the predicate device." However, a specific adjudication method (e.g., 2+1, 3+1 decision rule) is not explicitly stated. It seems to be a comparative evaluation aiming for no significant performance degradation.
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
- No MRMC comparative effectiveness study was done. This submission focuses on hardware modification (new detector) to an existing device, not an AI-assisted diagnostic tool. Therefore, the concept of improving human readers with AI assistance is not applicable here.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
- This is not an AI/algorithm-only device. The GM85 is an X-ray imaging system. The "standalone" performance here refers to the device's ability to produce images with acceptable quality on its own. Non-clinical data (MTF, DQE measurements) and phantom images contribute to demonstrating this standalone image performance. The evaluation by radiologists of the phantom images is more about confirming the quality of the "output" of the device in a clinical context, rather than evaluating an algorithm's diagnostic capability.
7. The Type of Ground Truth Used
- For the phantom image evaluation, the "ground truth" is established by the known characteristics of the anthropomorphic phantoms. The purpose of the radiologists' evaluation is to determine if the images produced by the new detector (compared to the predicate's detector) adequately represent these known phantom structures and maintain diagnostic quality. In essence, the ground truth is the known physical properties of the phantom, and the evaluation confirms the device's ability to render these properties accurately in images.
8. The Sample Size for the Training Set
- This submission describes a modification to an existing medical device's hardware (a detector), not an AI or machine learning algorithm. Therefore, there is no "training set" in the context of AI model development that would typically be described here. The device itself is "trained" or designed through engineering and validated through performance testing.
9. How the Ground Truth for the Training Set Was Established
- As there is no AI training set as commonly understood in this context, the concept of establishing ground truth for a training set does not apply. The device's design and engineering would be based on established physics principles of X-ray imaging and medical imaging standards.
§ 892.1720 Mobile x-ray system.
(a)
Identification. A mobile x-ray system is a transportable device system intended to be used to generate and control x-ray for diagnostic procedures. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.