TY - JOUR
TI - An automated image analysis method for the measurement of neutrophil
alkaline phosphatase in the prenatal screening of Down syndrome
AU - Tafas, T
AU - Cuckle, HS
AU - Nasr, S
AU - Krivchenia, EL
AU - Resvani, E
AU - and Evans, MI
JO - Fetal Diagnosis and Therapy
PY - 1996
VL - 11
TODO - 4
SP - 254-259
PB - Karger
SN - 1015-3837, 1421-9964
TODO - 10.1159/000264311
TODO - image analysis; automation; neutrophil alkaline phosphatase; prenatal
screening; Down syndrome
TODO - Objectives: (1) To develop an image analysis method for the measurement
of neutrophil alkaline phosphatase (NAP); (2) To establish a correlation
of urea-resistant fraction of NAP (URNAP)/NAP scoring between the manual
and automated methods, and (3) to assess the value of URNAP/NAP in the
prenatal screening of Down syndrome. Study Design: Slides from 15
unaffected controls were blindly scored by both methods. The Pearson
test was used for correlation analysis. Slides from 15 Down syndrome
pregnancies and 25 unaffected controls were scored manually. Results: A
coefficient r = 0.93 was obtained comparing the URNAP/NAP scores
generated by the two methods, Average time for scoring by the automated
method was 8 min. The median URNAP/NAP values for Down syndrome and
unaffected controls were 112/86.1 and 51/51.5, respectively.
Conclusions: Scores obtained by both methods highly correlate. Automated
scoring is threefold faster, Down syndrome cases have higher URNAP/NAP
scores compared to unaffected controls, which suggests that URNAP/NAP is
an extremely useful marker for mid-trimester prenatal screening.
ER -