(213 days)
PeriFlux 6000 equipped with PF 6010 is intended for measuring micro-vascular perfusion in skin and muscle in humans. It is also intended for measuring micro-vascular perfusion in all tissues in animals for research purposes. The PF 6010 is also intended for evaluating tissue response in skin to local heating and providing temperature stabilization of skin at blood perfusion measurement.
PeriFlux 6000 equipped with PF 6050 is intended for measuring the pressure cuffs, to simplify simultaneous measurements of perfusion and pressure when used in conjunction with a laser Doppler perfusion monitor. PeriFlux 6000 equipped with PF 6050 is also intended for Pulse Volume Recording (PVR) on human limbs and digits for diagnosis and evaluation of vascular disease in adults. It is not intended for use on neonates and pregnant women.
PeriFlux 6000 equipped with PF 6040 is intended for continuous non-invasive transcutaneous monitoring of the partial pressures of oxygen and/or carbon dioxide. It is intended for use on neonates, pediatrics, and adults not under gas anesthesia.
The PeriFlux 6000 is a modular multichannel system that offers several tests for diagnosis and evaluation of vascular disease in one instrument. It consists of a Main Unit (PF 6001), which accommodates up to eight different function units of the same type or of different types enabling simultaneous measurements of several parameters. Currently, one type of unit –PF 6040 tcpO2/pCO2 Unit– is available for the US market. Two more units have been developed:
- PF 6010 LDPM/Temp Unit
- PF 6050 Pressure Unit
The PeriFlux 6000 equipped with PF 6010 function units measures microcirculatory blood flow using Laser Doppler technology. In combination with the PF 6050 function unit to inflate blood pressure cuffs and to register the cuff pressure, it enables a range of different tests, including ankle pressure, toe pressure, skin perfusion pressure (SPP), pulse volume recording (PVR), segmental pressures, heat provocations and post-occlusive reactive hyperemia (PORH).
In Laser Doppler Perfusion Monitoring, an optical fibre leads light generated by a laser to the LDPM probe tip, which rests against the tissue. The beam of light will enter the tissue and become scattered. Blood cells moving within the volume illuminated by the beam will cause the light to change frequency. This change in frequency is called a Doppler shift and it is used to calculate the blood flow in the illuminated tissue.
Here's an analysis of the acceptance criteria and study information based on the provided text, focusing on what is present and explicitly stating what is not available:
1. Table of Acceptance Criteria and Reported Device Performance
The provided text does not explicitly state specific numerical acceptance criteria for the PeriFlux 6000. Instead, it relies on a comparison to a predicate device (PeriFlux System 5000) and describes general claims of "very good correlation" and "equivalence" between the new device and the predicate.
| Acceptance Criteria (Explicitly Stated) | Reported Device Performance (as described) |
|---|---|
| Not explicitly defined numerically. The primary acceptance criterion appears to be "substantial equivalence" to the predicate device. | For Laser Doppler Perfusion Monitoring (LDPM), the "signals correlate very well between the two systems and that they can be regarded as equivalent." |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: The document does not specify a sample size for the performance tests conducted. It only mentions "tests" in plural, implying more than one data point, but no quantity.
- Data Provenance (country of origin, retrospective/prospective): The document does not specify the country of origin for the test data, nor does it state whether the data was retrospective or prospective.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of those Experts
The document does not mention the use of experts to establish ground truth for the test set. The performance testing described (bench testing of signal correlation) appears to be an objective comparison between device outputs rather than an expert-adjudicated ground truth.
4. Adjudication Method for the Test Set
Since experts are not mentioned in establishing ground truth, an adjudication method like 2+1 or 3+1 is not applicable and not described in the document.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done, and the Effect Size of How Much Human Readers Improve with AI vs. Without AI Assistance
- MRMC Study: No. The device is a "Cardiovascular Blood Flowmeter" and a "Modular multichannel system for diagnosis and evaluation of vascular disease." It is a measurement device, not an AI-assisted diagnostic tool that would involve human readers interpreting output. Therefore, an MRMC study is not applicable and was not performed.
- Effect Size of Human Reader Improvement with/without AI: Not applicable, as there's no AI component or human reader interpretation discussed.
6. If a Standalone (algorithm only without human-in-the-loop performance) was Done
The performance testing described ("Bench Testing") for the Laser Doppler Perfusion Monitoring (LDPM) unit (PF 6010) appears to be a form of standalone testing. The document states:
"We have therefore tested how the clinically relevant parameter, blood perfusion, correlates between these two systems. The tests show that the signals correlate very well between the two systems and that they can be regarded as equivalent."
This suggests the device's output (blood perfusion measurement) was compared to the predicate device's output independently, without human interpretation as part of the primary performance evaluation. So, yes, a form of standalone performance was assessed by comparing the device's measurements directly to a predicate device.
7. The Type of Ground Truth Used
The "ground truth" for the performance testing of the PeriFlux 6000's blood perfusion measurement (PF 6010) was the measurement output of the legally marketed predicate device, PeriFlux System 5000 (PF 5010). The document states "how the clinically relevant parameter, blood perfusion, correlates between these two systems."
For the pressure measurement (PF 6050) and temperature measurement and control (PF 6010 and PF 6050 functionalities), the document states: "Temperature and pressure are measured using the same technology and use the same type of sensors in PeriFlux 6000 as in PeriFlux System 5000." This implies the predicate device's established performance serves as the "ground truth" reference.
8. The Sample Size for the Training Set
The document does not mention any "training set." This device is a physiological measurement tool, not an AI/machine learning system that typically requires a training set.
9. How the Ground Truth for the Training Set was Established
Since no training set is mentioned, the method for establishing its ground truth is not applicable and not described.
§ 870.2100 Cardiovascular blood flowmeter.
(a)
Identification. A cardiovascular blood flowmeter is a device that is connected to a flow transducer that energizes the transducer and processes and displays the blood flow signal.(b)
Classification. Class II (performance standards).