Accuracy of magnetic resonance imaging and transvaginal ultrasonography in the diagnosis, mapping, and measurement of uterine myomas.

OBJECTIVE: The purpose of this study was to evaluate and compare the accuracy of magnetic resonance imaging and transvaginal ultrasonography in myoma diagnosis, mapping, and measurement. STUDY DESIGN: This was a double-blind study of 106 consecutive premenopausal women who underwent hysterectomy for benign reasons. Myomas (total, 257) were exactly mapped by magnetic resonance imaging and transvaginal ultrasonography; in each patient, we counted correctly identified myomas with pathologic position as true value. RESULTS: The presence of myomas was detected with the same high level of precision by both methods (magnetic resonance imaging: sensitivity, 0.99; specificity, 0.86; transvaginal ultrasonography: sensitivity, 0.99; specificity, 0.91). The mean number of correctly identified myomas was significantly higher by magnetic resonance imaging than by transvaginal ultrasonography (mean difference, 0.51 +/- 1.03; P <.001), a difference that narrowed to 0.08 +/- 0.76 (P =.60) in 26 patients with 1 to 4 myomas and uterine volumes <375 mL. Magnetic resonance imaging and transvaginal ultrasonography myoma diameter measurements had equal and high accuracies in patients with 1 to 4 myomas. CONCLUSION: Transvaginal ultrasonography is as efficient as magnetic resonance imaging in detecting myoma presence, but its capacity for exact myoma mapping falls short of that of magnetic resonance imaging, especially in large (>375 mL) multiple-myoma (>4) uteri.

Reproducibility of evaluation of the uterus by transvaginal sonography, hysterosonographic examination, hysteroscopy and magnetic resonance imaging.

BACKGROUND: The aim was to evaluate and compare inter-observer reproducibility by magnetic resonance imaging (MRI), transvaginal ultrasonography (TVS), hysterosonographic examination (HSE) and hysteroscopy (HY). METHODS: Different observers consecutively evaluated MRI, TVS, HSE and HY independently in 51 pre-menopausal women, who underwent hysterectomy for benign diseases. RESULTS: Inter-observer agreement (kappa) was as follows: Exclusion of uterine cavity abnormalities: MRI 0.97, TVS 0.68, HSE 0.48 and HY 0.63; submucous myomas: MRI 0.97, TVS 0.59, HSE 0.60 and HY 0.67; polyps: MRI 0.49, TVS 0.48, HSE 0.35 and HY 0.50; identification of myometrial myomas: MRI 0.97, TVS 0.74; adenomyosis: MRI 0.73 and TVS 0.38. Mean difference between observers in number of observed myomas was (absolute values) MRI 0.58, TVS 0.93. Agreement on evaluation of abnormalities in the uterine cavity, submucous myomas, number of myomas and adenomyosis was significantly greater by MRI than by any of the other techniques, whereas agreement was in line by TVS, HSE and HY. CONCLUSIONS: Inter-observer disagreement reached substantial levels only for exclusion of uterine cavity benign abnormalities by HY, TVS and HSE. Strategies should be adopted to reduce observer variation of common gynaecological imaging techniques or the less observer-dependent MRI technique could be favoured.