Opposite result was concluded by Byun et al., who compared 3D bFFE with 3D DRIVE using 3T MRI machine, and his study revealed that the 3D DRIVE was better than the 3D bFFE yet it was not statis-tically significant, the less image quality of 3D bFFE in his study regarding the cochlear turns may be attributed to the banding artifact induced by the strong magnetic susceptibility effect inherent to the GRE technique and as the susceptibility changes increase linearly with field strength, it means that the susceptibility artifact is more problematic at 3T and less apparent at 1.5T, this explained why we did not encounter such problem in our study which was done on 1. Although our results showed that there was no statistically significant difference between 3D bFFE and 3D DRIVE for demarcation of the cochlear turns and the cochlear basal turn mean diameter, yet it revealed that the 3D bFFE was slightly better than 3D DRIVE for demonstration of the cochlear apical, middle and basal turns, this was matched with Lane et al., who revealed that there was no difference between FGRE and FRFSE sequences for delineation of cochlear turns. Our results were matched with the Tsuchiya et al., and Jung et al., who also reported that the 3D bFFE was better than 3D DRIVE for demarcation of vestibulocochlear nerve, yet different results were seen in other studies lane et al., who compared 3D CISS which is one of FGRE sequence with 3D FRFSE and his study concluded that there was no difference between two sequence in the demarcation of ICA cranial nerves, yet Byun et al., revealed that the 3D DRIVE was better than 3D bFFE for visualization of IAC cranial nerves. Our study revealed that the 3D bFFE was generally better than the 3D DRIVE for the demarcation of the IAC cranial nerves, as the 3D bFFE was statistically better than 3D DRIVE for visualization of the cochlear nerve as well as the inferior and superior vestibular nerves within the internal auditory canal and it was slightly better for demonstration of internal auditory canal facial nerve segment, these finding was attributed to the less pulsation and blurring artifacts noted in the 3D bFFE and the better contrast resolution between the nerves of internal auditory canal and the surrounding CSF yielding better demarcation of the cranial nerves. The discrepancies were more prominent for the basal turn of the cochlea, vestibule, and all semicircular canals, and were thought to be attributed to the presence of greater magnetic susceptibility artifacts inherent to gradient-echo techniques such as bFFE.īecause of higher image quality and less susceptibility artifacts, we highly recommend the employment of 3D DRIVE imaging as the MR imaging choice for the IAC and inner ear.

Two neuroradiologists reviewed both MR images with particular attention to the visibility of the anatomic structures, including four branches of the cranial nerves within the IAC, anatomic structures of the cochlea, vestibule, and three semicircular canals.Īlthough both techniques provided images of relatively good quality, the 3D DRIVE sequence was somewhat superior to the 3D bFFE sequence.

Thirty ears of 15 subjects (7 men and 8 women age range, 22-71 years average age, 50 years) without evidence of ear problems were examined on a whole-body 3T MR scanner with both 3D DRIVE and 3D bFFE sequences by using an 8-channel sensitivity encoding (SENSE) head coil. To compare the use of 3D driven equilibrium (DRIVE) imaging with 3D balanced fast field echo (bFFE) imaging in the assessment of the anatomic structures of the internal auditory canal (IAC) and inner ear at 3 Tesla (T).

Labeled internal auditory canal mri