The effect of image size on nuchal translucency measurement.
OBJECTIVE
To assess the effect of altering image size on the absolute nuchal translucency (NT) measurement.


METHODS
NT was measured at three image magnifications (60%, 100% and 200%) in 120 singleton pregnancies.


RESULTS
The mean +/- SD NT measurements were 1.52 +/- 0.57 mm, 1.35 +/- 0.53 mm and 1.18 +/- 0.48 mm at 60%, 100% and 200% magnification, respectively (p = 0.00001).


CONCLUSIONS
The measurement of NT decreases significantly with increasing image size. Optimisation of NT as a method of screening will require agreed standardisation of image magnification.
Edwards
Andrew
A
Fetal Diagnostic Unit, Monash Medical Centre, Monash University, Clayton, Victoria, Australia.
Mulvey
Sheila
S
Wallace
Euan M
EM
D000293:Adolescent; D000328:Adult; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000379:methods*; D008423:Maternal Age; D009333:Neck / Q000000981:diagnostic imaging* / Q000196:embryology; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D018566:Pregnancy, High-Risk; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D016216:Ultrasonography, Prenatal / Q000379:methods* / Q000592:standards