(62 days)
It is intended for accurate transit time blood volume flow measurements during cardiovascular, vascular and transplantation surgery.
The Medi-Stim Butterfly Flowmeter estimates blood volume flow by measuring the transit time difference between an ultrasonic signal propagated through a blood vessel in the downstream direction and one propagated in the upstream direction. The measuring unit consists of two ultrasonic transducers on one side of the vessel aimed at a common point on a flat reflector on the other side of the vessel.
Here's a breakdown of the acceptance criteria and study information for the Medi-Stim Butterfly Flowmeter, based on the provided 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Probe Accuracy) | Reported Device Performance |
|---|---|
| Perivascular probes: ±10% | Perivascular: ±10% |
| Cardiac output probes: ±15% | Cardiac output: ±15% |
| Tubing probes: ±5% | Tubings: ±5% |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample size used for the test set or the data provenance (e.g., country of origin, retrospective or prospective nature of the study). The submission primarily focuses on comparing the new device to a predicate device based on technical specifications and intended use.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
This information is not provided in the document. The submission relies on a comparison to a predicate device and established accuracy criteria for similar devices, rather than a clinical study with expert-established ground truth.
4. Adjudication Method for the Test Set
This information is not provided in the document, as no explicit clinical test set with adjudicated ground truth is described.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
A multi-reader multi-case (MRMC) comparative effectiveness study was not conducted or reported in this 510(k) summary. The submission focuses on substantial equivalence to a predicate device based on technical specifications.
6. Standalone (Algorithm Only) Performance
A standalone performance study of the algorithm without human-in-the-loop performance was not explicitly described or reported as a separate study. However, the accuracy percentages (e.g., ±10% for perivascular) refer to the device's inherent measurement accuracy, implying a form of standalone technical performance assessment against known flow rates. The document states: "The flowmeter displays the measurement results with a flow curve and it's associated mean flow value." This suggests the algorithm is directly providing measurements.
7. Type of Ground Truth Used
The ground truth for the declared accuracy percentages (e.g., ±10%, ±15%, ±5%) is implied to be an objective measurement of "true" blood volume flow during device testing, likely established through controlled experiments or calibrated flow models. The document doesn't specify the exact method (e.g., gold-standard flow measurement devices, in-vitro testing with known flow rates). The comparison to the predicate device's accuracy implies that the acceptance criteria are based on established standards for this type of medical device.
8. Sample Size for the Training Set
The document does not mention a training set or any development of an AI algorithm in the context of machine learning. The device described uses a "transit time technology that interfaces with this platform" and "The transit time signal processing is performed by hardware that uses algorithms similar to an ultrasound scanner, and the received ultrasound phase shifts are processed digitally." This suggests traditional signal processing algorithms rather than trainable machine learning models.
9. How the Ground Truth for the Training Set Was Established
As no training set is mentioned (see point 8), this information is not applicable/not provided.
§ 892.1570 Diagnostic ultrasonic transducer.
(a)
Identification. A diagnostic ultrasonic transducer is a device made of a piezoelectric material that converts electrical signals into acoustic signals and acoustic signals into electrical signals and intended for use in diagnostic ultrasonic medical devices. Accessories of this generic type of device may include transmission media for acoustically coupling the transducer to the body surface, such as acoustic gel, paste, or a flexible fluid container.(b)
Classification. Class II.