The effect of image size on nuchal translucency measurement

Abstract

OBJECTIVES: 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.