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Updated: Dec 11, 2025

Real-Time Monitoring of Neurocritical Patients with Diffuse Optical Spectroscopies
Published on: November 19, 2020
Correlation Between the VerifyNow P2Y12 Assay and the Newly Developed APAL System in Neuroendovascular Patients
Kodai Uematsu1,2, Tasuku Sakayori3, Hidekazu Ishida4
1Department of Neurosurgery, Gifu Prefectural General Medical Center, Gifu uematsu-koudai@gifu-hp.jp.
Objective:
Light transmission aggregometry (LTA) is the gold standard method for assessing platelet function. Recently, a new parameter called adenosine diphosphate (ADP)-induced platelet aggregation level (APAL) was developed to aid interpretation of LTA results. APAL is a score calculated based on platelet aggregation patterns upon exposure to 1 μM and 10 μM ADP and is determined using an automated coagulation analyzer. We compared APAL and VerifyNow P2Y12 assay for neuroendovascular patients.
Methods:
42 patients who have received antiplatelet therapy were studied. Platelet function tests were performed on CS-2400 for APAL and VerifyNow P2Y12 assay was used for P2Y12 reaction unit (PRU) and % inhibition.
Results:
Moderate correlations were observed between APAL and PRU (r=0.64, p<0.001) and between APAL and % inhibition (r=-0.74, p<0.001). The optimal threshold for APAL was 8.2 for PRU (threshold=240) and 8.1 for % inhibition (threshold=26%). The percentage of agreement between the above thresholds was 90.9% between PRU and APAL and 77.3% between % inhibition and APAL.
Conclusions:
The APAL system exhibits moderate correlation with PRU and % inhibition. APAL testing is a good choice for a clinical laboratory already in possession of Sysmex CS series analyzers. In this setting, APAL testing can significantly decrease the cost of platelet function testing for patients on antiplatelet therapy.
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