Automated Blood Cell Analysis

Question 1

The detection and measurement of changes in electrical resistance produced by cells as they traverse a small aperture

Answer 1

Electronic impedance

Question 2

Display the pulses that are generated by cells as they interrupt the current

Answer 2

Oscilloscope

Question 3

The number of pulses is proportional to…..

Answer 3

The number of cells counted

Question 4

The height of the voltage pulse is proportional to….

Answer 4

The volume of the cell

Question 5

Increases RBC/PLT counting sensitivity

Answer 5

Aperture diaphragm size

Question 6

The passage of more than one cell at a time through the orifice causes artificially large pulses.

Causes falsely increased cell volumes and falsely decreased cell counts

Answer 6

Coincident passage

Question 7

Causes erroneous pulses and falsely increased cell counts

Answer 7

Recirculation of cells back into the sensing zone

Question 8

Provides laminar flow that allows the central sample stream to marrow sufficiently to separate and align the cells into single file passage through the sensing zone

Answer 8

Hydrodynamic focusing

Question 9

Resistance to high voltage EM current flowing between both electrodes simultaneously.

Measures conductivity to correlate cell interior density

Answer 9

Radio frequency

Question 10

A hydrodynamically focused sample stream is directed through a flow cell past a focused light source

Answer 10

Optical scatter

Question 11

Light source of flow cytometry

Answer 11

Tungsten halogen lamp or helium neon laser

Question 12

Light scatter results from absorption, diffraction, refraction to be detected and converted into electrical signals by photodetectors

Answer 12

Flow cytometry

Question 13

Forward angle light scatter correlates with

Answer 13

Call volume due to diffraction of light

Question 14

Side scatter correlates with

Answer 14

Degree of internal complexity due to refraction and reflection of light

Question 15

RBC principle instrument

Answer 15

Impedance

Question 16

WBC principle instrument

Answer 16

Optical scatter

Question 17

PLT principal instrument

Answer 17

Impedance and optical scatter

Question 18

MCV principal instrument

Answer 18

Mean of RBC volume distribution histogram (impedance)

Question 19

Increase MCV and MCHC and decreased RBC count

Answer 19

Cold agglutinins

Question 20

How to correct cold agglutinins

Answer 20

Warm specimen to 37C and rerun

Question 21

Increases HGB and MCH

Answer 21

Lipemia and Icterus

Question 22

How to correct lipemia, icterus

Answer 22

Plasma replacement

Question 23

Decreased RBC count and HCT

Answer 23

Hemolysis

Question 24

How to correct hemolysis

Answer 24

Request new specimen

Question 25

Decreased RBC and increased PLT counts

Answer 25

Microcytes of schistocytes

Question 26

Increased WBC counts and decreased PLT count

Answer 26

Platelet clumps

Question 27

Increased HGB and RBC and incorrect HCT

Answer 27

WBC >100,000

Question 28

RBC agglutinin histogram appearance

Answer 28

Large amounts of RBC over 100 fL