(129 days)
The HemoCue WBC system is indicated for use for quantitative determination of white blood cell (WBC) count in capillary or venous whole blood. The HemoCue WBC system is for In Vitro Diagnostic use only. The HemoCue WBC Analyzer is only to be used with HemoCue WBC Microcuvettes. The HemoCue WBC system is indicated for use in clinical laboratories and for point-of-care settings.
The system consists of the HemoCue WBC Analyzer together with specially designed microcuvettes, the HemoCue WBC Microcuvettes. The microcuvette serves both as a sample container and a reaction chamber. A blood sample of approximately 10 uL is drawn into the cavity by capillary action. A hemolysing agent lyses the red cells in the microcuvette and a staining agent colors the white blood cells. An image is taken of the stained white blood cells and the number of cells is counted by image analysis. The result is presented within 3 minutes on the analyzer's display. The system reports results in the measuring range 0.3 - 30.0 x107/L. The system is factory calibrated and needs no further calibration.
The HemoCue WBC Analyzer is a portable device. The main parts are the cuvette holder (in which the microcuvette is placed), the cuvette moving arm (brings the microcuvette into correct measuring position), a magnifying optic unit, a camera, image processing software, a display and a power adapter.
The HemoCue WBC Microcuvette is made of polystyrene plastic and contains saponin that hemolyzes the red blood cells, methylene blue that stains the white blood cells and nonactive reagents. A blood sample of approximately 10 µL is drawn into the cavity by capillary action. The microcuvette serves as a sample container and a reaction chamber. No dilution of the sample is required.
The provided text for HemoCue WBC System (K071652) is a 510(k) summary and approval letter, which serves to establish substantial equivalence to predicate devices rather than fully detailing acceptance criteria and studies demonstrating performance. The document states that "Studies were conducted in-house, in clinical laboratory settings and point of care settings to demonstrate the performance with intended specifications of the HemoCue WBC system and to validate that the intended user can easily operate the system and obtain results as expected." However, it does not provide specific details on the acceptance criteria, reported performance, or the methodologies of these studies.
Therefore, much of the requested information cannot be definitively extracted from the provided text.
Here's a breakdown of what can and cannot be answered based on the provided text:
1. A table of acceptance criteria and the reported device performance
This information is not explicitly provided in the given text. While it states that studies were conducted to "demonstrate the performance with intended specifications," it does not list these specifications or the corresponding results in a table format or any other detailed manner.
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
This information is not explicitly provided. The text mentions "in-house, in clinical laboratory settings and point of care settings" for studies but does not specify sample sizes or data provenance (country, retrospective/prospective).
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
This information is not provided. The text describes the device's technical characteristics and its indications for use, but it does not detail how ground truth was established for its validation studies.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
This information is not provided.
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
This is not applicable as the HemoCue WBC System is an automated cell counter, not an AI-assisted diagnostic tool for human readers. The comparison is against predicate devices (Sysmex XS-1000i and manual light microscopy), not human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, the HemoCue WBC System is described as a "semi-automated device" that performs its analysis via "image analysis" and presents a result. Therefore, the performance described would inherently be standalone performance of the device's algorithm without a human in the loop for the actual WBC count determination. The process involves filling a microcuvette, placing it in the analyzer, and receiving a result.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
This information is not explicitly provided. The comparison is made against a "Sysmex XS-system" and "manual light microscopic WBC method." It's highly probable that these predicate methods served as the ground truth or reference methods, but the text doesn't explicitly state how discrepancies were resolved or what constituted the ultimate "ground truth."
8. The sample size for the training set
This information is not provided.
9. How the ground truth for the training set was established
This information is not provided. The text focuses on the device's operation and regulatory equivalence, not the specifics of its development and training data.
§ 864.5200 Automated cell counter.
(a)
Identification. An automated cell counter is a fully-automated or semi-automated device used to count red blood cells, white blood cells, or blood platelets using a sample of the patient's peripheral blood (blood circulating in one of the body's extremities, such as the arm). These devices may also measure hemoglobin or hematocrit and may also calculate or measure one or more of the red cell indices (the erythrocyte mean corpuscular volume, the mean corpuscular hemoglobin, or the mean corpuscular hemoglobin concentration). These devices may use either an electronic particle counting method or an optical counting method.(b)
Classification. Class II (performance standards).