Driven equilibrium (drive) MR imaging of the cranial nerves V-VIII: comparison with the T2-weighted 3D TSE sequence.
OBJECTIVE
The aim of this study is to evaluate the efficacy of the driven equilibrium radio frequency reset pulse (DRIVE) on image quality and nerve detection when used in adjunction with T2-weighted 3D turbo spin-echo (TSE) sequence.


METHODS
Forty-five patients with cranial nerve symptoms referable to the cerebellopontine angle (CPA) were examined using a T2-weighted 3D TSE pulse sequence with and without DRIVE. MR imaging was performed on a 1.5-T MRI scanner. In addition to the axial resource images, reformatted oblique sagittal, oblique coronal and maximum intensity projection (MIP) images of the inner ear were evaluated. The nerve identification and image quality were graded for the cranial nerves V-VIII as well as inner ear structures. These structures were chosen because fluid-solid interfaces existed due to the CSF around (the cranial nerves V-VIII) or the endolymph within (the inner ear structures). Statistical analysis was performed using the Wilcoxon test. P < 0.05 was considered significant.


RESULTS
The addition of the DRIVE pulse shortens the scan time by 25%. T2-weighted 3D TSE sequence with DRIVE performed slightly better than the T2-weighted 3D TSE sequence without DRIVE in identifying the individual nerves. The image quality was also slightly better with DRIVE.


CONCLUSIONS
The addition of the DRIVE pulse to the T2-weighted 3D TSE sequence is preferable when imaging the cranial nerves surrounded by the CSF, or fluid-filled structures because of shorter scan time and better image quality due to reduced flow artifacts.
School of Radiology, University of Kocaeli, Derince, 41100, Turkey. eciftcis7@hotmail.com
E
E
Ciftci
Yonca
Y
Anik
Arzu
A
Arslan
Gur
G
Akansel
Tahsin
T
Sarisoy
Ali
A
Demirci
D000010:Abducens Nerve / Q000473:pathology; D000328:Adult; D000368:Aged; D016477:Artifacts; D002526:Cerebellar Diseases / Q000175:diagnosis*; D002528:Cerebellar Neoplasms / Q000175:diagnosis; D002530:Cerebellopontine Angle / Q000473:pathology; D002555:Cerebrospinal Fluid; D003287:Contrast Media; D003391:Cranial Nerves / Q000473:pathology*; D007758:Ear, Inner / Q000294:innervation; D004710:Endolymph; D005154:Facial Nerve / Q000473:pathology; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014276:Trigeminal Nerve / Q000473:pathology; D000159:Vestibulocochlear Nerve / Q000473:pathology
D003287:Contrast Media; D019786:Gadolinium DTPA