From the Department of Radiology (A.L., A.A.H., J.J.M.Z., J.C.W.S., J.H.) University Medical Center Utrecht, Utrecht, the Netherlands
From the Department of Radiology (A.L., A.A.H., J.J.M.Z., J.C.W.S., J.H.) University Medical Center Utrecht, Utrecht, the Netherlands.
AJNR Am J Neuroradiol. 2018 Jun;39(6):1112-1120. doi: 10.3174/ajnr.A5629. Epub 2018 Apr 19.
Intracranial vessel wall MR imaging plays an increasing role in diagnosing intracranial vascular diseases. For a complete assessment, pre- and postcontrast sequences are required, and including other sequences, these result in a long scan duration. Ideally, the scan time of the vessel wall sequence should be reduced. The purpose of this study was to evaluate different intracranial vessel wall sequence variants to reduce scan duration, provided an acceptable image quality can be maintained.
Starting from the vessel wall sequence that we use clinically (6:42 minutes), 6 scan variants were tested (scan duration ranging between 4:39 and 8:24 minutes), creating various trade-offs among spatial resolution, SNR, and contrast-to-noise ratio. In total, 15 subjects were scanned on a 3T MR imaging scanner: In 5 subjects, all 7 variants were performed precontrast-only, and in 10 other subjects, the fastest variant (4:39 minutes) and our clinically used variant (6:42 minutes) were performed pre- and postcontrast.
The fastest variant (4:39 minutes) had higher or comparable SNRs/contrast-to-noise ratios of the intracranial vessel walls compared with the reference sequence (6:42 minutes). Qualitative assessment showed that the contrast-to-noise ratio was most suppressed in the fastest variant of 4:39 minutes and the variant of 6:42 minutes pre- and postcontrast. SNRs/contrast-to-noise ratios of the fastest variant were all, except one, higher compared with the variant of 6:42 minutes ( < .008). Furthermore, the fastest variant (4:39 minutes) detected all vessel wall lesions identified on the 6:42-minute variant.
A 30% faster vessel wall sequence was developed with high SNRs/contrast-to-noise ratios that resulted in good visibility of the intracranial vessel wall.
颅内血管壁磁共振成像在诊断颅内血管疾病方面发挥着越来越重要的作用。为了进行全面评估，需要进行对比前和对比后序列，并且包括其他序列，这导致扫描时间较长。理想情况下，血管壁序列的扫描时间应缩短。本研究旨在评估不同的颅内血管壁序列变体，以缩短扫描时间，同时保持可接受的图像质量。
从我们临床使用的血管壁序列（6:42 分钟）开始，测试了 6 种扫描变体（扫描时间在 4:39 分钟至 8:24 分钟之间），在空间分辨率、SNR 和对比噪声比之间进行了各种权衡。总共对 15 名受试者在 3T 磁共振成像扫描仪上进行了扫描：在 5 名受试者中，所有 7 种变体均进行了仅对比前扫描，而在另外 10 名受试者中，最快的变体（4:39 分钟）和我们临床使用的变体（6:42 分钟）进行了对比前和对比后扫描。
最快的变体（4:39 分钟）与参考序列（6:42 分钟）相比，颅内血管壁的 SNR/对比噪声比更高或相当。定性评估显示，最快的 4:39 分钟变体和 6:42 分钟的对比前和对比后变体对对比度噪声比的抑制最为明显。除了一个变体外，最快变体的 SNR/对比噪声比均高于 6:42 分钟变体（<.008）。此外，最快的变体（4:39 分钟）检测到了在 6:42 分钟变体上发现的所有血管壁病变。
开发了一种 30%更快的血管壁序列，具有较高的 SNR/对比噪声比，可很好地显示颅内血管壁。
