Alfonso Fausto MD, Presenter: Research Consultant, Bracco Group

Alessandro Preziosa BS, MS, Abstract Co-Author: Employee, General Electric Company

Luca Gaburro MS, Abstract Co-Author: Employee, General Electric Company

Giorgio Rizzatto MD, Abstract Co-Author: Research Consultant, General Electric Company

Luca Volterrani MD, Abstract Co-Author: Nothing to Disclose

To test feasibility, accuracy and reproducibility of breast ultrasound (US) with contrast-enhanced magnetic resonance (MR) volume navigation and fusion imaging as a reference (V Nav), a new tool to obtain US and MR image co-registration.

We evaluated five healthy women volunteers (44.8±12.3 years, range 33–65) using contrast-enhanced breast MR acquired in supine position and US with a high-resolution linear probe. MR data were uploaded in US equipment before performing unilateral breast exam. US and MR co-registration was obtained by means of an external electromagnetic transmitter and two small magnetic receivers on a linear probe bracket by coupling three fiducial points. V Nav software displayed a real time multiplanar reconstructed MR image during live US exam on the same display. Image alignment was assessed using five points of interest. Misalignment was measured on skin surface as distance between real and expected transducer position considering the corresponding marker on MR image. Two independent experienced radiologists recorded time to co-registration and twice measured image misalignment. Pair t-Student test, Wilcoxon test and Bland-Altman plot were used.

In all subjects V Nav was obtained. Time to co-registration was 9 ± 3 and 10 ± 3 minutes, respectively (p=0.656). A total of one hundred measurements were done for image misalignment evaluation; mean and SD were 0.42±0.32 cm, 0.58±0.41 cm (p=0.161) and 0.50±0.32 cm and 0.56±0.52 cm (p=0.928), respectively.

Our study showed that breast US with V Nav is a reliable technique. Intra and interobserver evaluation showed a low systematic error independently by two operators.

US and MR co-registration will probably open new perspectives in lesion detection visible at least with one modality and to contain interventional procedure costs.

Fausto, A, Preziosa, A, Gaburro, L, Rizzatto, G, Volterrani, L, Feasibility, Accuracy, and Reproducibility of Breast US with Volume Navigation and Fusion Imaging Using Contrast-enhanced MR as a Reference.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9012106.html