Comparison of the amniotic fluid index with gray-scale and color Doppler ultrasound.
OBJECTIVE
This study was undertaken to compare the amniotic fluid index (AFI) obtained with gray-scale ultrasound and color Doppler.


METHODS
We examined 77 patients ranging from 22 to 41 weeks' gestation with two of five sonographers obtaining two measures of the AFI utilizing gray-scale and color Doppler.


RESULTS
Of the measurements of AFI, 96% showed the gray scale measurement to be greater than the color measurement (p < 0.0001; mean 9.3 +/- 3.3 cm vs. 8.5 +/- 3.0 cm). At gray-scale AFI < 5 cm, color AFI was essentially the same, but at gray-scale AFI 5-10 cm, color AFI was < 5 cm, 15.2% and 7.8% of the time. At gray-scale AFI > 10 cm, no color AFI was < 5 cm. Individual (n = 5) interobserver reliability was r = 0.79 (p < 0.0001) and intraobserver reliability was r = 0.94 (p < 0.0001).


CONCLUSIONS
AFI by color Doppler was always less than with gray scale. At an AFI of 5-10 cm, color demonstrated an AFI of < 5 cm in up to 16% of patients, and increased the diagnosis of oligohydramnios.
Goldkrand
J W
JW
Memorial Health University Medical Center, Savannah, Georgia, USA.
Hough
T M
TM
Lentz
S U
SU
Clements
S P
SP
Bryant
J L
JL
Hodges
J A
JA
D000653:Amniotic Fluid / Q000000981:diagnostic imaging*; D005260:Female; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D018615:Ultrasonography, Doppler, Color