(131 days)
The Liverscan Mobile is intended to provide shear wave speed measurements and estimates of tissue stiffness as well as ultrasound coefficient of attenuation (MAP: Mobile Attenuation Parameter) in internal structures of the body. The shear wave speed and stiffness measurements may be used as an aid to clinical management of adult patients with liver disease.
The Liverscan Mobile is indicated for non-invasive measurement in the liver of 50 Hz shear wave speed and estimates of stiffness as well as determining a 3.5MHz ultrasound coefficient of attenuation (MAP: Mobile Attenuation Parameter).
The shear wave speed and stiffness, and MAP may be used as an aid to diagnosis and monitoring of adult patients with liver disease, as part of an overall assessment of the liver.
This device is designed to be used in a doctor's office to measure the stiffness and ultrasonic attenuation of the liver in patients with liver disease. It does so in a painless and completely noninvasive manner.
The Liverscan Mobile is intended to provide shear wave speed measurements and estimates of tissue stiffness as well as ultrasound coefficient of attenuation (MAP: Mobile Attenuation Parameter) in internal structures of the body. The shear wave speed and stiffness measurements may be used as an aid to clinical management of adult patients with liver disease.
The Liverscan Mobile is indicated for non-invasive measurement in the liver of 50 Hz shear wave speed and estimates of stiffness as well as determining a 3.5MHz ultrasound coefficient of attenuation (MAP: Mobile Attenuation Parameter).
The shear wave speed and stiffness, and MAP may be used as an aid to diagnosis and monitoring of adult patients with liver disease, as part of an overall assessment of the liver.
The provided text does not contain detailed information about specific acceptance criteria and a study proving the device meets them in terms of clinical performance (e.g., accuracy, sensitivity, specificity for diagnostic purposes). Instead, the document focuses on demonstrating substantial equivalence to a predicate device through non-clinical bench tests.
Here's an analysis based on the information available:
1. A table of acceptance criteria and the reported device performance
The document provides a "Safety factor & Performance Comparison" table (Table 2 on page 8), but this primarily compares technical specifications and compliance with general medical device standards rather than specific clinical performance criteria.
| Safety factor & Performance | Proposed Device Performance | Acceptance Criteria (Implied) |
|---|---|---|
| Electrical Safety | Compliance with IEC 60601-1 | Compliance with IEC 60601-1 |
| EMC | Compliance with IEC 60601-1-2 | Compliance with IEC 60601-1-2 |
| Usability | Compliance with IEC 60601-1-6 | Compliance with IEC 60601-1-6 |
| Usability Engineering | Compliance with IEC 62366-1 | Compliance with IEC 62366-1 |
| Software | Compliance with IEC 62304 | Compliance with IEC 62304 |
| Biocompatibility | Compliance with ISO 10993-1 | Compliance with ISO 10993-1 |
| Performance | Compliance with IEC 60601-2-37/ IEC 62359: 2017/ IEC 61161 | Compliance with IEC 60601-2-37/ IEC 62127-1/ IEC 62127-03/ IEC 61161 |
| VCTETM Range (Shear wave speed) | 0.7-5.0 m/s | Similar to predicate device (0.8-5.0 m/s) |
| VCTETM Range (Stiffness) | 1.5-75 kPa | Similar to predicate device (2.0-75 kPa), with verification that 1.5kPa can be measured. |
| Attenuation Range (MAP value) | 100-400 dB/m | Similar to predicate device (100-400 dB/m) |
Study Proving Acceptance Criteria:
The document states, "Bench tests were conducted to verify that the proposed device met all design specifications as was Substantially Equivalent (SE) to the predicate device. The test results demonstrated that the proposed device complies with the following standards." (Page 13)
And on page 15, it concludes: "All the test results demonstrate the Liverscan Mobile meets the requirements of its pre-defined acceptance criteria and intended uses, and is substantially equivalent to the predicate devices."
The study proving the device meets its acceptance criteria is a series of non-clinical bench tests. These tests focused on:
- Electrical safety: Compliance with IEC6060-1:2005+A1:2012+A2:2020
- Electromagnetic compatibility (EMC): Compliance with IEC 60601-1-2:2014 /AMD1:2020
- Basic Safety And Essential Performance: Compliance with IEC 60601-2-37, IEC 62359: 2017, and IEC 61161
- Usability: Compliance with IEC 60601-1-6 and IEC 62366-1
- Software Verification and Validation Testing: Conducted as per FDA's guidance, with the software classified as "Moderate" level of concern.
- Biocompatibility testing: Compliance with ISO 10993-1, ISO 10993-10, and ISO 10993-23.
- Function test (General term, no specifics provided in the excerpt).
2. Sample sized used for the test set and the data provenance
The document explicitly states: "No clinical test data was used to support the decision of substantial equivalence." (Page 15) Therefore, there is no clinical test set, nor information on its sample size, country of origin, or whether it was retrospective or prospective. The tests performed were non-clinical bench tests.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
Not applicable, as no clinical test set or human-interpreted ground truth was used for assessing clinical performance. The "ground truth" for the non-clinical tests would be the established international standards and specifications.
4. Adjudication method for the test set
Not applicable, as no clinical test set requiring human adjudication was used.
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. The device is a "Portable Liver Elastography Ultrasound Diagnostic System" which provides shear wave speed and attenuation measurements. It's not described as an AI-powered diagnostic aid for human readers, nor was a clinical comparative effectiveness study performed.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This device appears to be a standalone measurement device. However, the evaluation was based on non-clinical bench testing for compliance with safety and performance standards, not a specific standalone performance study in a clinical context (e.g., diagnostic accuracy against a clinical ground truth). The document repeatedly refers to its function as providing measurements and estimates, which are then "used as an aid to diagnosis and monitoring of adult patients with liver disease, as part of an overall assessment of the liver." This implies that the device provides data that a clinician (human-in-the-loop) interprets for diagnosis and monitoring.
7. The type of ground truth used
For the non-clinical bench tests, the "ground truth" was compliance with established international standards for medical electrical equipment, EMC, usability, software, biocompatibility, and specific ultrasound performance standards. For example, for "Electrical Safety," the ground truth was meeting the requirements of IEC60601-1.
8. The sample size for the training set
Not applicable. The document does not describe the development of an AI algorithm that requires a training set for clinical applications. The "software verification and validation testing" mentioned is for the device's operating software, not an AI model.
9. How the ground truth for the training set was established
Not applicable, as there is no mention of a training set for an AI algorithm.
§ 892.1560 Ultrasonic pulsed echo imaging system.
(a)
Identification. An ultrasonic pulsed echo imaging system is a device intended to project a pulsed sound beam into body tissue to determine the depth or location of the tissue interfaces and to measure the duration of an acoustic pulse from the transmitter to the tissue interface and back to the receiver. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II (special controls). A biopsy needle guide kit intended for use with an ultrasonic pulsed echo imaging system only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.