(57 days)
The HemoScreen is a point-of-care (POC) automated hematology analyzer intended for the enumeration and classification of the following parameters in capillary and venous whole blood (K2EDTA anticoagulated): WBC, RBC, HCT, MCV, MCH, MCHC, RDW, PLT, MPV, NEUT%, NEUT#, LYMP%, LYMP#, MONO%, MONO#, EO%, EO#, BASO%, and BASO#. The HemoScreen is for in vitro diagnostic use in clinical laboratories and/or POC settings for adults and children at least 2 years of age.
HemoScreen is a point of care (POC), automated hematology analyzer that provides 20 common CBC parameters, including a 5-part leukocyte (WBC) differential, in capillary and venous whole blood samples. The HemoScreen analyzer (reader) is a tabletop device that is designed to use with a disposable reagent Cartridge. In addition to the Cartridge, the system includes a disposable Sampler with two glass capillaries which is used to collect the blood sample and then transfer it to the Cartridge.
Once the Cartridge is inserted into the reader, there are no further procedural steps; blood is expelled from the capillaries (Sampler) into the reagent compartments (Cartridge). The reader then mixes the blood sample with the reagents by alternately pressing compressible portions of the Cartridge, eventually causing the suspension of cells to flow into the microfluidic chamber. Cells flowing in the microfluidic chamber focus into a single-cell plane due to a patented physical phenomenon known as viscoelastic focusing.
The reader then captures images of the focused cells and analyzes them in real time using machine vision algorithms. When analysis is complete, the results are displayed to the user on the reader's touch screen and may be printed to an adjacent printer or exported to a USB flash drive. The Cartridge is ejected by the analyzer after analysis, and can then be safely disposed of, as the reagents and blood sample remain within the Cartridge.
The basic staining and microscopic image analysis performed by HemoScreen closely resembles the traditional blood smear and the hemocytometer counting chamber. Leukocytes are classified based on their staining properties and morphology, whereas absolute counts are obtained by counting the cells contained in a chamber of predetermined volume. Test results are obtained within less than six (6) minutes and the results are saved.
Quality Control: Commercial 3-level liquid quality controls, PIX-CBC Hematology Controls, are recommended for use with the HemoScreen. These controls cover all the tested parameters and are sampled the same way whole blood is sampled.
Software: The HemoScreen software displays an intuitive, simple-to-use user interface that is operated via the touch screen. The software is responsible for operating the device, performing the measurements, and recording the results.
The PixCell Medical Technologies HemoScreen Hematology Analyzer (K240636) demonstrated substantial equivalence to its predicate device (K222148) with extended analytical measuring ranges for WBC and PLT. The device performance was validated through non-clinical and performance validation studies.
Here's a breakdown of the acceptance criteria and study details:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state acceptance criteria in table format but implies that the criteria were met if the comparison to the predicate device (Sysmex XN) showed strong correlation and acceptable Passing-Bablok regression results. The reported device performance is presented in the "Passing-Bablok regression and Pearson's correlation of HemoScreen vs. Sysmex XN" table. As the conclusion states, "The data indicated that the predefined acceptance criteria were met for all the 20 measurands and in all tested ranges."
| Parameter | Reported HemoScreen Result Range | Reported Correlation Coefficient (r) | Reported Passing-Bablok Intercept | Reported Passing-Bablok Slope | Acceptance Criteria (Implied: Strong correlation (r close to 1), Intercept close to 0, Slope close to 1) |
|---|---|---|---|---|---|
| WBC (10³/µL) | 0.29-94.77 | 0.995 | -0.034 | 0.999 | Met |
| RBC (10⁶/µL) | 1.91-7.13 | 0.997 | 0.023 | 0.998 | Met |
| HGB (g/dL) | 5.65-20.72 | 0.995 | -0.006 | 0.993 | Met |
| HCT (%) | 16.42-62.73 | 0.990 | -0.180 | 1.006 | Met |
| MCV (fL) | 53.33-111.47 | 0.928 | 1.818 | 0.979 | Met |
| MCH (pg) | 16.94-37.24 | 0.970 | 0.970 | 0.953 | Met |
| MCHC (g/dL) | 30.90-36.06 | 0.654 | 10.582 | 0.677 | Met |
| RDW (%) | 11.32-27.34 | 0.911 | 0.411 | 0.955 | Met |
| PLT (10³/µL) | 9.25-930.66 | 0.990 | 0.705 | 0.983 | Met |
| MPV (fL) | 9.27-14.46 | 0.825 | -0.432 | 1.055 | Met |
| NEUT (10³/µL) | 0.00-83.11 | 0.994 | -0.042 | 1.017 | Met |
| LYMP (10³/µL) | 0.01-72.19 | 0.947 | 0.011 | 0.998 | Met |
| ΜΟΝΟ (10³/µL) | 0.01-9.48 | 0.930 | -0.006 | 1.006 | Met |
| EOS (10³/µL) | 0.00-4.10 | 0.946 | 0.008 | 0.998 | Met |
| BASO (10³/µL) | 0.00-0.77 | 0.415 | -0.006 | 0.758 | Met |
| NEUT (%) | 0.9-98.20 | 0.961 | 0.158 | 1.012 | Met |
| LYMP (%) | 1.30-93.10 | 0.980 | 0.717 | 0.986 | Met |
| ΜΟΝΟ (%) | 0.10-45.80 | 0.877 | -0.146 | 1.005 | Met |
| EO (%) | 0.00-34.10 | 0.855 | 0.087 | 1.016 | Met |
| BASO (%) | 0.00-6.50 | 0.277 | -0.076 | 0.764 | Met |
2. Sample size used for the test set and the data provenance
- Sample Size for performance validation (WBC, PLT extended ranges): 232 residual whole blood venous samples.
- Data Provenance: The linearity study was conducted at PixCell Medical, Israel. The document does not specify the country of origin for the 232 venous samples, nor explicitly states if the samples were retrospective or prospective, but "residual whole blood venous samples" usually implies retrospective use of leftover clinical samples.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
The document does not mention the use of experts to establish ground truth for the test set. The validation was a method comparison study against a legally marketed predicate device, the Sysmex XN-Series (XN-10, XN-20) Automated Hematology Analyzers (K112605). The Sysmex analyzer served as the reference method.
4. Adjudication method for the test set
Not applicable. The study compares the HemoScreen to a commercially available predicate device (Sysmex XN), not against a human-adjudicated ground truth.
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. This device is an automated hematology analyzer, not an AI-assisted diagnostic tool that involves human readers interpreting results.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, the performance validation data presented is for the standalone device (HemoScreen Hematology Analyzer), with its measurements compared directly to those of the Sysmex XN automated hematology analyzer. There is no human-in-the-loop component described for this specific validation.
7. The type of ground truth used
The ground truth for the performance validation study was established using a legally marketed predicate device: Sysmex XN-Series (XN-10, XN-20) Automated Hematology Analyzers (K112605). This is a comparative method study, where the predicate device acts as the reference standard.
8. The sample size for the training set
The document does not provide information about a training set size. This suggests that the study performed here focused on analytical validation of the device's measurement accuracy against a predicate, rather than an AI/machine learning model whose performance would depend on a training set. The device uses "machine vision algorithms" but the specifics of their training and associated dataset sizes are not detailed in this 510(k) summary.
9. How the ground truth for the training set was established
Not applicable, as a training set and its ground truth establishment are not described in this 510(k) summary.
§ 864.5220 Automated differential cell counter.
(a)
Identification. An automated differential cell counter is a device used to identify one or more of the formed elements of the blood. The device may also have the capability to flag, count, or classify immature or abnormal hematopoietic cells of the blood, bone marrow, or other body fluids. These devices may combine an electronic particle counting method, optical method, or a flow cytometric method utilizing monoclonal CD (cluster designation) markers. The device includes accessory CD markers.(b)
Classification. Class II (special controls). The special control for this device is the FDA document entitled “Class II Special Controls Guidance Document: Premarket Notifications for Automated Differential Cell Counters for Immature or Abnormal Blood Cells; Final Guidance for Industry and FDA.”