Keywords:
Quality assurance, Image verification, Technical aspects, Surgery, Intraoperative, MR, Neuroradiology brain, MR physics, Interventional non-vascular
Authors:
C. Gagliardo1, A. Napoli2, L. Geraci1, G. COLLURA1, M. Marrale1, T. V. Bartolotta1, C. Catalano2, M. Midiri1, R. Lagalla1; 1Palermo/IT, 2Rome/IT
DOI:
10.1594/ecr2018/C-0012
Methods and materials
The focused ultrasound equipment (ExAblate 4000,
InSightec Ltd.
- Haifa,
Israel) installed in our Department integrates with an MRI unit operating at 1.5T (Signa HDxt,
GE Medical System - Milwaukee,
Wisconsin,
USA) and consists of a hemispheric 1024-element phased-array transducer operating at 650 kHz as those used with 3T MRI units.
The use of 3T MRI scanners allows the use of the MR systems body RF coil for treatment planning and real-time thermal monitoring with reasonable compromises in terms of signal to noise ratio (SNR) [3].
To achive a resonable quality using a 1.5T unit a dedicated flexible head coil was developed (2-channel FUS-Head,
InSightec Ltd.
- Haifa,
Israel) (Figure 1 and 2).
To compare the imaging quality of MRI’s body RF coil and the dedicated flexible coil the NEMA (2008) method for measuring the SNR was used [4].
T2w-FRFSE images were obtained from a dedicated Dose Quality Assurance (DQA) phantom using the same MRI protocol subsequently used for real treatments.