Magnetic resonance imaging and transvaginal ultrasound for determining fibroid burden: implications for research and clinical care.
OBJECTIVE
To compare magnetic resonance and ultrasound imaging for uterine fibroid measurement.


METHODS
Eighteen women undergoing hysterectomy for symptomatic fibroids underwent preoperative pelvic ultrasound and magnetic resonance imaging. Resected fibroids were correlated with the images. Weighted kappa agreement statistics and Spearman correlations for patient characteristics were calculated.


RESULTS
Magnetic resonance imaging identified 121 of 151 pathologically confirmed fibroids, yielding 91% positive predictive value (95% confidence interval [CI], 85-95) and 80% sensitivity (95% CI, 73-86). Positive predictive value and sensitivity for ultrasound were 97% (95% CI, 89-100) and 40% (95% CI, 32-48), respectively. Mean diameter-equivalent discrepancies between imaging and pathologic measurements were 0.51 +/- 0.68 cm for magnetic resonance imaging and 0.76 +/- 0.88 cm for ultrasound. kappa statistics comparing imaging to pathology showed better agreement for magnetic resonance than ultrasound (kappa = 0.60 vs 0.36). The number of fibroids detected by magnetic resonance imaging predicted measurement errors (r = 0.76; P = .0002).


CONCLUSIONS
Superior sensitivity and minimal measurement discrepancies suggest magnetic resonance imaging may be preferentially used for fibroid assessment in clinical research.
Levens
Eric D
ED
Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Wesley
Robert
R
Premkumar
Ahalya
A
Blocker
Wendy
W
Nieman
Lynnette K
LK
D005260:Female; D006801:Humans; D007044:Hysterectomy; D007889:Leiomyoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000592:standards*; D011237:Predictive Value of Tests; D011300:Preoperative Care; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014463:Ultrasonography / Q000592:standards*; D014621:Vagina / Q000000981:diagnostic imaging