Three-dimensional and reconstructed ultrasonography in gestational trophoblastic disease

Background: Hydatidiform mole (HM) and hydropic degeneration of the placenta (HDP) may present with similar clinical symptoms and signs. Sometimes, ultrasound pictures do not provide the necessary definition to distinguish HDP in abortions from a complete or partial molar pregnancy. The purpose of this study was to attempt to evaluate the potential advantages of three-dimensional (3-D) ultrasound in the differential diagnosis of gestational trophoblastic disease. Materials and Methods: From October 1994 to September 1996, 10 pregnant women with abnormal vaginal bleeding were studied using a 3-D transvaginal 7.5-MHz volume probe or transabdominal 5-MHz probe (Kretztechnik, Combison 530, Voluson, Austria) on suspicion of having gestational trophoblastic disease. Results: Three-dimensional ultrasound clearly demonstrated multiple sonolucent cystic lesions of various sizes in both conditions, but the cysts of HDP tended to coalesce into a larger space in the central portion of the uterine cavity, while in HM, the coalesced areas were seen to have localized peripherally after image reconstruction. Conclusion: The advent of 3-D ultrasound and computer-processed image reconstruction can aid in evaluating the entire uterine cavity. In this preliminary study, the use of two-dimensional ultrasound could not differentiate HM from HDP in any of the 10 cases, while 3-D ultrasound failed to distinguish in only two cases. However, data from more patients with gestational trophoblastic disease are needed to establish a definite role for 3-D imaging in the differential diagnosis of gestational trophoblastic disease.