Doctorate program in Clinical Medicine and Public Health, University of Granada, Spain.
Department of Experimental Psychology, University of Granada, Spain.
Magn Reson Med. 2017 Oct;78(4):1464-1468. doi: 10.1002/mrm.26529. Epub 2016 Oct 25.
This study describes a new methodology-the cold pressor gel test (CPGT)-for delivering an accessible experimental pain stimulus, which is reproducible and safe for functional MRI (fMRI).
The cold pressor test was modified to put safety precautions into the CPGT. The material used is cool gelled water with a thickening product, which provides a stable temperature at 0.2 °C. Thirteen women with chronic pelvic pain were scanned using a 3 Tesla (T) MR scanner equipped with a 12-channel head coil. Changes in BOLD activation during cold-induced pain were estimated.
The results have demonstrated that gel substances maintain a stable temperature during the experiment, resulting in an insignificant variation. Before the experiment, the mean temperature was 0.2 ± 0.11 °C, and at the end it was 0.7 ± 0.15 °C. The time taken by participants to reach the maximum level of pain during the CPGT was 56.92 ± 11.09 s. The pain intensity during the experiments was 6.92 ± 1.66 on the visual analog scale (VAS). The fMRI analysis showed significant BOLD activation in the main brain regions involved in chronic pain processing.
The CPGT is an experimental tool to deliver pain that is easily reproducible, particularly in brain functional imaging studies. Moreover, it is cost-effective, safe, and compatible with fMRI. Magn Reson Med 78:1464-1468, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
本研究描述了一种新的方法——冷加压凝胶测试（CPGT），用于提供可及的实验性疼痛刺激，该方法具有可重复性且对功能磁共振成像（fMRI）安全。
对冷加压测试进行了修改，将安全预防措施纳入 CPGT 中。所用材料为冷却凝胶水和增稠产品，可将温度稳定在 0.2°C。使用配备 12 通道头部线圈的 3 特斯拉（T）MR 扫描仪对 13 名患有慢性盆腔疼痛的女性进行扫描。估计冷诱导疼痛期间 BOLD 激活的变化。
结果表明，凝胶物质在实验过程中保持稳定的温度，变化不明显。实验前平均温度为 0.2±0.11°C，实验结束时为 0.7±0.15°C。参与者在 CPGT 中达到最大疼痛水平所需的时间为 56.92±11.09 s。实验过程中的疼痛强度为视觉模拟量表（VAS）上的 6.92±1.66。fMRI 分析显示，慢性疼痛处理的主要大脑区域的 BOLD 激活明显。
CPGT 是一种易于复制的疼痛传递实验工具，特别是在脑功能成像研究中。此外，它具有成本效益、安全且与 fMRI 兼容。磁共振医学 78：1464-1468，2017。©2016 国际磁共振学会。
