Visualization of cranial nerves I-XII: value of 3D CISS and T2-weighted FSE sequences

Abstract

The aim of this study was to evaluate the sensitivity of the three-dimensional constructive interference of steady state (3D CISS) sequence (slice thickness 0.7 mm) and that of the T2-weighted fast spin echo (T2-weighted FSE) sequence (slice thickness 3 mm) for the visualization of all cranial nerves in their cisternal course. Twenty healthy volunteers were examined using the T2-weighted FSE and the 3D CISS sequences. Three observers evaluated independently the cranial nerves NI-NXII in their cisternal course. The rates for successful visualization of each nerve for 3D CISS (and for T2-weighted FSE in parentheses) were as follows: NI, NII, NV, NVII, NVIII 40 of 40 (40 of 40), NIII 40 of 40 (18 of 40), NIV 19 of 40 (3 of 40), NVI 39 of 40 (5 of 40), NIX, X, XI 40 of 40 (29 of 40), and NXII 40 of 40 (4 of 40). Most of the cranial nerves can be reliably assessed when using the 3D CISS and the T2-weighted FSE sequences. Increasing the spatial resolution when using the 3D CISS sequence increases the reliability of the identification of the cranial nerves NIII-NXII.

Dynamic Quantitative T1 Mapping in Orthotopic Brain Tumor Xenografts

“…The 0.2-mmol/kg dose of Optimark afforded more complete tumor detection of these small glioma tumors than the standard clinical dose of 0.1-mmol/kg. Several studies in which administration of higher doses of contrast agent significantly improved the enhancement of intracranial tumors clinically [20] , [21] , [22] , [23] , [24] corroborate our findings. The T1 mapping sequence and quantitative maps provide an objective quantitative method for detection of small tumors and for the measurement of tumor enhancement over time.…”

Clinical Significance of Prenatal and Postnatal Heavily T2-Weighted Magnetic Resonance Images in Patients with Myelomeningocele

“…The thin slices that can be obtained with hT2WI provide high-resolution images with excellent contrast between CSF and solid structures such as nerves or vessels [12,13]. …”

Compared with the Conventional MR Imaging, Do the Constructive Interference Steady State Sequence and Diffusion Weighted Imaging Aid in the Diagnosis of Lumbar Disc Hernias?

“…As a short TE and low flip angle is employed, the CISS sequence is amenable to 3D acquisition, high T2/T1 and high CSF/ nerve contrast and accentuated T2 weighting. Therefore, the CISS sequence can provide a myelographic image with excellent CSF-to-spinal cord contrast and visualization of the thecal sac and dural root sleeves at each intervertebral level [4,10,13]. Its disadvantage, similar to other gradient echo sequences, is its high sensitivity to motion.…”

“…Therefore, flow can easily result in a loss of signals due to pulsatile CSF motion. However, CISS variants, such as Free Induction with Steady-State precession (FISP) pulses and compensation, can be applied over each TR cycle, making this modality quite suitable for imaging the neural structures [4,10]. The sequence cannot properly differentiate discs from osteophytes, but it can easily reveal the site of injury and demonstrate the effects on the thecal sac and spinal cord [1,4].…”

“…CISS sequence: The 3D-steady-state refocused gradientecho sequence is flow-compensated, high-contrast and highspatial resolution with the slice thickness reduced to 0.7 mm, resulting in detailed visualization and differentiation of the various components of the nerve roots, vessels, CSF and the neural structures surrounded by CSF [4,5,10]. Therefore, this sequence has been mostly used in the assessment of cranial nerves to evaluate their pathologies in the cerebellopontine angle and inner ear [5,[10][11][12]. As a short TE and low flip angle is employed, the CISS sequence is amenable to 3D acquisition, high T2/T1 and high CSF/ nerve contrast and accentuated T2 weighting.…”