Do measurements of uterine septum using three-dimensional ultrasound and magnetic resonance imaging agree?

Objective: To evaluate the agreement between measurements of uterine septum by 3-D ultrasound (3-D US) and magnetic resonance imaging.

Methods: Fourteen women with a uterine septum underwent both a 3-D US and an MRI followed by hysteroscopic metroplasty in a tertiary care infertility clinic within a university teaching hospital. The agreement between 3-D US and MRI measurements of septum length (SL), septum width (SW) and the distance between fundal serosa and septal tip (SSD) was compared using the Bland Altman limit of agreement analysis.

Results: 3-D US correctly identified all women who had a uterine septum identified with MRI. The mean difference in SL was 2.7 mm (upper limit of agreement and lower limit of agreement were 10.3 mm and -4.8 mm, respectively). The mean difference in SW was 2.3 mm (upper limit of agreement and lower limit of agreement of 10.4 mm and -9.2 mm, respectively). The SSD mean difference was 2.8 mm (upper limit of agreement and lower limit of agreement of 10.6 mm and -5 mm, respectively).

Conclusions: Categorical agreement in diagnosis was 100% and agreement between 3-D US and MRI measurements was good with narrow differences. Variations were unlikely to be greater than intra- and inter-observer variations anticipated in MRI readings. 3-D US can replace MRI for diagnosis and measurement of uterine septa.