Purpose: Considering the number of multiple sclerosis (MS) patients referred for clinical spinal cord imaging, the optimization of imaging protocols plays a crucial role. We aimed to evaluate the use of proton density (PD) turbo spin-echo (TSE) with spectral attenuated inversion recovery (SPAIR) fat suppression and compare it with the currently recommended T2-TSE-SPAIR in sagittal plane in cervical spinal cord imaging.
Methods: In this study 35 MS patients with clinically suspected or known spinal cord lesions were scanned on a 3.0T magnetic resonance imaging (MRI) system. In addition to the routine protocol, PD-TSE-SPAIR sequences were obtained to quantitatively and qualitatively evaluate lesion detectability and image quality compared to T2-TSE-SPAIR sequences. Quantitative analysis was based on measurements of lesion-to-cord contrast ratio (LCCR), lesion contrast-to-noise ratio (LCNR) and lesion dimensions and the qualitative analysis on ranking with a predetermined score scale. The presence of lesions in these sequences was verified in axial T2 multi-echo gradient echo images.
Results: In quantitative analysis, the lesions on PD-TSE-SPAIR had statistically significantly higher contrast (p < 0.05), according to the statistical test of LCCR, LCNR calculated contrast and measured lesion dimensions. Qualitative analyses were congruent with quantitative results; the median rank of PD-TSE-SPAIR was significantly higher than T2-TSE-SPAIR (p < 0.05). Of the 34 detected lesions 9 (26%) were not visualized in T2-TSE-SPAIR sequence.
Conclusion: Considering its superiority in contrast ratios and lesion dimensions when compared to T2-TSE-SPAIR in both qualitative and quantitative analyses, we therefore recommend PD-TSE-SPAIR as a pivotal sequence to evaluate demyelinating spinal cord lesions at 3T.
Keywords: Cervical spinal cord; Magnetic resonance; Multiple sclerosis.