Noworolski Susan M, Crane Jason C, Vigneron Daniel B, Kurhanewicz John
Department of Radiology, University of California, San Francisco, San Francisco, California 94107, USA.
J Magn Reson Imaging. 2008 May;27(5):1077-82. doi: 10.1002/jmri.21331.
To compare the data quality and ease of use of four endorectal-coil probe setups for prostate MRI.
Four endorectal-coil probe setups were compared: 1) air-inflated probe; 2) perfluorocarbon (PFC)-inflated probe; 3) rigid, smaller prototype coil; and 4) rigid, smaller coil designed for biopsying the prostate. Signal-to-noise ratio (SNR), positioning, shimming, MRI motion artifact, and MR spectroscopic imaging (MRSI) spectral quality were assessed.
Rigid coils provided approximately 2.5-fold higher SNR than inflatable coils near the peripheral zone midline. The biopsy probe sensitivity decreased dramatically by the apex. The rigid probes, as compared to the inflatable probes, took longer to place (10 +/- 2 vs. 7 +/- 2 minutes, P < 0.0002), tended to be placed too superiorly, required repositioning more often (73% vs. 20%, P < 0.003), and had higher motion artifacts (P < 0.001). Shimming time was least for the PFC-inflated probe (2 +/- 0.5 minutes, P < 0.05). The air-inflated probe produced larger linewidths (P < 0.01) and tended to have longer shim times (7 +/- 4 minutes) and poorer spectral quality.
The inflatable coil is a good clinical choice due to ease of use, good coverage, and low motion artifacts. PFC-inflation is recommended as it provided higher quality data than air-inflation. The rigid, smaller probes have higher SNR and produce less tissue distortion and may be preferred for certain applications.
比较用于前列腺MRI的四种直肠内线圈设置的数据质量和易用性。
比较了四种直肠内线圈设置：1）充气探头；2）全氟化碳（PFC）充气探头；3）刚性较小的原型线圈；4）专为前列腺活检设计的刚性较小的线圈。评估了信噪比（SNR）、定位、匀场、MRI运动伪影和磁共振波谱成像（MRSI）谱质量。
在周边区中线附近，刚性线圈的SNR比可充气线圈高约2.5倍。活检探头在前列腺尖部的灵敏度显著降低。与可充气探头相比，刚性探头放置时间更长（10±2分钟对7±2分钟，P<0.0002），往往放置位置过高，需要更频繁地重新定位（73%对20%，P<0.003），且运动伪影更高（P<0.001）。PFC充气探头的匀场时间最短（2±0.5分钟，P<0.05）。充气探头产生的线宽更大（P<0.01），匀场时间往往更长（7±4分钟），谱质量更差。
由于易用性、良好的覆盖范围和低运动伪影，可充气线圈是一种不错的临床选择。推荐使用PFC充气，因为它提供的数据质量高于空气充气。刚性较小的探头具有更高的SNR，产生的组织变形更小，在某些应用中可能更受青睐。
