(112 days)
The iU22 Diagnostic Ultrasound System is intended for diagnostic ultrasound imaging in B (or 2-D), M-mode (including Anatomical M-mode), Pulse Wave Doppler, Continuous Wave Doppler, Color Doppler, Tissue Doppler Imaging, Harmonics (Tissue and Contrast) and Elastography modes (including ElastPQ). It is indicated for diagnostic ultrasound imaging and fluid flow analysis in the following applications: Ophthalmic Fetal Intra-operative Abdominal Laparoscopic Pediatric Small Organ Adult and Neonatal Cephalic Trans-rectal Trans-vaginal Musculoskeletal Urology Cardiac (Adult, Pediatric, Trans-esophageal) Fetal Echo Peripheral Vessel. The clinical environments where the iU22 4.3 system can be used include point-of-care areas in offices, clinical and hospital settings for diagnosis of patients.
The subject of this 510(k) notification, the modifications to the iU22 ultrasound system and transducer(s), function in a manner identical to all diagnostic ultrasound systems and transducers. The system circuitry generates an electronic voltage pulse, which is transmitted to the transducer. In the transducer, a piezo electric array converts the electronic pulse into an ultrasonic pressure wave. When coupled to the body, the pressure wave transmits through body tissues. The Doppler functions of system process the Doppler shift frequencies from the echoes of moving targets such as blood to detect and graphically display the Doppler shifts of these tissues as flow. ElastPQ is the Philips Ultrasound marketing name for a feature commonly referred to as shear wave elastography. The terms will be used interchangeably throughout the submission and supplemental information. The ElastPQ (shear wave) feature provides the user with tissue stiffness information. The iU22 Ultrasound system was cleared for Elastography modes per 510(k) K093563. ElastPQ is an Elastography mode on the iU22 Ultrasound Scanner where a burst of Doppler-type "push" pulses with high intensity and long pulse duration is transmitted. This mode creates waves in soft tissues and estimates the tissue stiffness by determining the speed at which these shear waves travel. This shear wave technology is similar to the ShearWave™ feature recently cleared on Aixplorer® by SuperSonic Imagine, Inc, per 510(k) K112255. The iU22 system gives the operator the ability to measure anatomical structures and offers analysis packages that provide information used by competent healthcare professionals to make a diagnosis.
Here's a summary of the acceptance criteria and study information based on the provided K130499 Philips iU22 Diagnostic Ultrasound System 510(k) Premarket Notification:
The document focuses on the Philips iU22 Diagnostic Ultrasound System, specifically the addition of a new ElastPQ (shear wave elastography) feature to the existing system.
1. Table of Acceptance Criteria and Reported Device Performance
The FDA submission for K130499 does not provide specific acceptance criteria or reported device performance in the format of a table as typically seen for clinical endpoints. Instead, it relies on substantial equivalence to predicate devices and adherence to safety standards.
The document states the following regarding performance:
- ElastPQ Measurement Report: "A bench test of the iU22 ultrasound system in ElastPQ mode in order to verify precision and reproducibility." (Page 3)
- Software Verification and Validation: "Standard verification and validation testing in order to ensure the system meets specifications and user needs." (Page 3)
However, specific quantitative metrics for precision, reproducibility, or other performance characteristics for ElastPQ are not provided in this document.
2. Sample Size Used for the Test Set and Data Provenance
A formal "test set" with patient data as commonly understood in algorithm performance studies is not explicitly described for the ElastPQ feature in this 510(k) submission.
- The document states: "A clinical trial was not required to demonstrate safety and effectiveness of the ElastPQ Elastography mode." (Page 3)
- It mentions: "A usability study on ElastPQ was performed following the FDA's draft guidance on human factors (June 2011). This work was conducted to ensure the ElastPQ analysis package meets the usability needs of the users." (Page 4)
Given these statements, it's highly improbable that a test set of patient data with a defined sample size for evaluating ElastPQ's diagnostic performance was used or reported in this submission. The "usability study" would likely involve human users interacting with the device, but not for diagnostic efficacy against a ground truth.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
Since a formal test set for diagnostic performance of ElastPQ is not described in the document, there is no information on the number or qualifications of experts used to establish a ground truth.
4. Adjudication Method for the Test Set
As there is no described test set for diagnostic performance, there is no information on an adjudication method.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
No, an MRMC comparative effectiveness study is not mentioned in the document. The submission states that "A clinical trial was not required to demonstrate safety and effectiveness of the ElastPQ Elastography mode."
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
The document mentions "ElastPQ Measurement Report: A bench test of the iU22 ultrasound system in ElastPQ mode in order to verify precision and reproducibility." This "bench test" could be considered a form of standalone performance evaluation, but it's not a diagnostic performance study against clinical ground truth. No standalone diagnostic performance study is described.
7. The Type of Ground Truth Used
For the ElastPQ feature, the document does not describe the use of a specific type of ground truth (e.g., pathology, outcomes data, expert consensus) for evaluating its diagnostic performance. The focus is on technical verification (precision, reproducibility through bench testing) and usability, rather than diagnostic accuracy.
8. The Sample Size for the Training Set
Since no clinical trial or machine learning-based diagnostic performance study is described for ElastPQ, there is no information on a training set or its sample size.
9. How the Ground Truth for the Training Set was Established
As no training set is described for ElastPQ, there is no information on how its ground truth would have been established.
Summary of the K130499 Submission's Approach to Acceptance Criteria and Study:
This 510(k) submission primarily leverages the concept of substantial equivalence to predicate devices (Philips iU22 K093563, SuperSonic Aixplorer K112255) for the new ElastPQ feature. The core arguments for safety and effectiveness are based on:
- Technical equivalence: The ElastPQ technology is described as similar to the cleared ShearWave™ feature on Aixplorer (K112255).
- Adherence to safety standards: Compliance with IEC standards, AIUM/NEMA standards, and FDA guidance for acoustic output limits.
- Bench testing: "ElastPQ Measurement Report" to verify precision and reproducibility (details not provided).
- Software verification and validation: Ensuring the system meets specifications and user needs.
- Usability study: To ensure the analysis package meets user needs (details not provided).
- No clinical trial required: The FDA accepted the argument that a clinical trial was not necessary to demonstrate safety and effectiveness, likely due to the established safety profile of ultrasound systems and the perceived incremental nature of the ElastPQ feature in the context of predicate devices.
Therefore, for the ElastPQ feature, the "acceptance criteria" appear to be met by demonstrating technical performance (precision and reproducibility via bench testing), software reliability, usability, and adherence to safety regulations, all within the framework of substantial equivalence to existing cleared devices rather than a direct clinical performance study with predefined metrics and ground truth.
§ 892.1550 Ultrasonic pulsed doppler imaging system.
(a)
Identification. An ultrasonic pulsed doppler imaging system is a device that combines the features of continuous wave doppler-effect technology with pulsed-echo effect technology and is intended to determine stationary body tissue characteristics, such as depth or location of tissue interfaces or dynamic tissue characteristics such as velocity of blood or tissue motion. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.