Accuracy of three-dimensional ultrasonography in differential diagnosis of septate and bicornuate uterus compared with office hysteroscopy and pelvic magnetic resonance imaging.

STUDY OBJECTIVE

To estimate the accuracy of 3-dimensional (3-D) ultrasonography in the differential diagnosis of septate and bicornuate uterus compared with office hysteroscopy and pelvic magnetic resonance imaging (MRI).

DESIGN

Prospective cohort study (Canadian Task Force Classification II-2).

SETTING

University hospital.

PATIENTS

Thirty-one patients referred with a suspected diagnosis of septate (n = 20) or bicornuate (n = 11) uterus.

INTERVENTIONS

All patients underwent 3-D ultrasonography displaying the rebuilt coronal view of the uterus, office hysteroscopy, and pelvic MRI. Operative hysteroscopic assessment and treatment was performed in case of sonographically diagnosed septate uterus. Bicornuate uterus was confirmed by laparoscopy.

MAIN OUTCOMES MEASURES

Concordance between suspected diagnosis with 3-D ultrasonography, hysteroscopy, and pelvic MRI and final diagnosis.

RESULTS

A septate uterus was diagnosed with 3-D ultrasonography in 29 patients and bicornuate uterus in 2 patients. Hysteroscopic transcervical section of the uterine septum was achieved in the 29 patients. Bicornuate uterus was laparoscopically confirmed in the 2 patients. Concordance between ultrasonography and operative hysteroscopy or laparoscopy was verified in all 31 cases. Twenty-five uterine septa and 5 bicornuate uteri were diagnosed by hysteroscopy (3 false-positive diagnoses of bicornuate uterus, 1 unfeasible hysteroscopy). Hysteroscopic diagnosis was correct in 27/30 patients. Twenty-four septate uteri and 7 bicornuate uteri were diagnosed by MRI (5 false-positive diagnoses of bicornuate uterus). Two complete septate uteri diagnosed by MRI were finally confirmed as incomplete septate uteri after 3-D ultrasonography and operative hysteroscopy. MRI diagnosis was correct in 24/31 patients.

CONCLUSION

Transvaginal 3-D ultrasonography appears to be extremely accurate for the diagnosis and classification of congenital uterine anomalies, more than office hysteroscopy and MRI. It may conveniently become the only mandatory step in the assessment of the uterine cavity in patients with a suspected septate or bicornuate uterus.