3D turbo field echo with diffusion-sensitized driven-equilibrium preparation technique (DSDE-TFE) versus echo planar imaging in evaluation of diffusivity of retinoblastoma.

Abstract

Compared with echoplanar (EP) diffusion-weighted imaging (DWI), three-dimensional (3D) turbo field echo with diffusion-sensitized driven-equilibrium (DSDE-TFE) preparation DWI obtains images with higher spatial resolution and less susceptibility artefacts. The purpose of this study was to evaluate the feasibility of DSDE-TFE to visualize retinoblastomas compared with EP imaging. This retrospective study was approved by our institutional review boards. Eight patients with retinoblastomas (five males and three females; age range 0-87 months; median 21 months) were studied. For the DSDE-TFE, motion-probing gradients (MPGs) were conducted at one direction with b-values of 0 and 500 s mm-2 and a voxel size of 1.5 × 1.5 × 1.5 mm3. For the EP imaging, MPGs were conducted at three directions with b-values of 0 and 1000 s mm-2 and a voxel size of 1.4 × 1.8 × 3 mm3. The apparent diffusion coefficients (ADCs) of each lesion were measured. Statistical analyses were performed with Pearson R and linear correlation coefficients. Intraocular lesions were clearly visualized on the DSDE-TFE without obvious geometrical distortion, whereas all showed deformity on EP images. On the DSDE-TFE, the ADCs of the lesions ranged from 0.83 × 10-3 to 2.93 × 10-3 mm2 s-1 (mean ± standard deviation 1.73 ± 0.73 × 10-3 mm2 s-1). On the EP images, the ADCs ranged from 0.53 × 10-3 to 2.03 × 10-3 mm2 s-1 (0.93 ± 0.53 × 10-3 mm2 s-1). There was a significant correlation in ADC measurement between the DSDE-TFE and EP imaging (r = 0.81, p < 0.05). With its insensitivity to field inhomogeneity and high spatial resolution, the 3D DSDE-TFE technique enabled us to assess diffusivity in retinoblastomas. Advances in knowledge: DSDE-TFE could enable us to assess the ADC of retinoblastomas without obvious geometrical distortion.