OLS CASY TT - Cell Count Higher than Hemocytometer

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Troubleshooting
. Amount of Cells Higher than the Count in the
Hemocytometer
The amount of cells counted with the CASY Instrument when using aggregation correction can be
higher compared to the count in the hemocytometer, even when no aggregates can be seen in the
hemocytometer.
Cell clusters behave dierently than single cells when sucked into the slit of a counting chamber.
Most of the big clusters never reach the central part where the cells are counted, because they are
moving too slowly. Big cell clusters often cannot be seen just for statistical reasons. Assuming that
some big cell clusters may exist, which occur with a probability of 1:1,000 compared to single cells,
the chance to see such a big cell cluster would only be about once in 10 measurements, since you
can see 100 events in the area of the counting elds only.
With the CASY Instrument, the statistical situation is much better, causing also big cell clusters to be
detected and quantied accurately. Therefore, in most cases the CASY Instrument results are higher,
but more accurate than the results of counting chambers.
If the results must be directly comparable to the results of a hemacytomter used previously:
1
Switch o the aggregation correction.
In this case, the underestimation of the correct cell number is comparable to a counting chamber.
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Amount of Cells Higher than the Count in the Hemocytometer