OC03.01: MRI and ultrasound fusion imaging for ovarian tumor

Abstract

Precise imaging diagnosis of ovarian tumor is a major issue for operative management. A combination of magnetic resonance imaging (MRI) images with real time high-resolution ultrasound known as fusion imaging may improve gynecologic pathologies investigations such as ovarian tumors. This study was undertaken to evaluate the feasibility of using fusion of MRI and ultrasound (US) in ovarian tumor characterisation. This prospective bicentric study included 25 patients referred for ovarian tumor diagnosed by US. All cases underwent 1.5 Tesla MRI protocol including at least 3 T2-weighted planes, with diffusion sequence and dynamic series. The Digital Imaging and Communications in Medicine volume dataset was then loaded into the US system for manual registration of the live US image and fusion imaging examination. The results of the fusion were then compared with US and MRI results alone. Ovarian tumors could be investigated by fusion imaging. US was more efficient to characterise small vegetations whereas T2-weighted MRI was limited by the size of the vegetations. The use of the color Doppler added a vascular criteria which could help the interpretation of the fusion imaging. The diagnosis of malignant tumor was improved by the use of the fusion thank to the complementarity of US and MRI and the addition of the malignant criteria. Multimodality fusion imaging is feasible to investigate ovarian tumors, as US and MRI are complementary. The combination of real time MRI and US image fusion could help to characterise ovarian tumors when the interpretation was difficult by isolated US and MRI.