评估犬模型低温脊髓损伤发展条件：冷冻消融治疗转移性脊柱肿瘤的安全性实验研究。
Evaluation of Conditions for the Development of Cryogenic Spinal Cord Injury Using a Canine Model: An Experimental Study on the Safety of Cryoablation for Metastatic Spinal Tumors.
机构信息
From the Department of Orthopedic Surgery (M.K., S.K., S.D., N.Y., R.A., H.T.), Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
From the Department of Orthopedic Surgery (M.K., S.K., S.D., N.Y., R.A., H.T.), Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
出版信息
AJNR Am J Neuroradiol. 2024 Apr 8;45(4):424-431. doi: 10.3174/ajnr.A8151.
BACKGROUND AND PURPOSE
Although the application of cryoablation to metastatic spinal tumors has been attempted, spinal cryoablation has the unique complication of cryogenic spinal cord injury. This study aimed to elucidate the conditions for the development of cryogenic spinal cord injury.
MATERIALS AND METHODS
Fifteen canines were used in this study. A metal probe was inserted into the 13th thoracic vertebral body. Cryoablation was performed for 10 minutes by freezing the probe in liquid nitrogen. The control canine underwent probe insertion only. Spinal cord monitoring, epidural temperature measurement, motor function assessment, and pathologic examination of the spinal cord were performed.
RESULTS
During the 10 minutes of cryoablation, the epidural temperature decreased and reached the lowest epidural temperature (LET) at the end of cryoablation. The LETs (degrees celsius [°C]) of each canine were -37, -30, -27, -8, -3, -2, 0, 1, 4, 8, 16, 18, 20, and 25, respectively. As the epidural temperature decreased, waveform amplitudes also decreased. At the end of cryoablation (10 minutes after the start of cryoablation), abnormal waves were observed in 92.9% (13/14) of canines. With epidural rewarming, the amplitude of the waveforms tended to recover. After epidural rewarming (2 hours after the start of cryoablation), abnormal waves were observed in 28.6% (4/14) of canines. The LETs (°C) of the canines with abnormal waves after epidural rewarming were -37, -30, -27, and -8. None of the canines with normal waves after epidural rewarming had any motor impairment. In contrast, all canines with remaining abnormal waves after epidural rewarming had motor impairment. In the pathologic assessment, cryogenic changes were found in canines with LETs (°C) of -37 -30, -27, -8, 0, and 1.
CONCLUSIONS
This study showed that 10-minute spinal cryoablation with LETs (°C) of -37, -30, -27, -8, 0, and 1 caused cryogenic spinal cord injury. There was no evidence of cryogenic spinal cord injury in canines with LET of ≥4°C. The epidural temperature threshold for cryogenic spinal cord injury is between 1 and 4°C, suggesting that the epidural temperature should be maintained above at least 4°C to prevent cryogenic spinal cord injury.
背景与目的
虽然冷冻消融已应用于转移性脊柱肿瘤，但冷冻脊柱消融存在独特的低温脊髓损伤并发症。本研究旨在阐明低温脊髓损伤的发展条件。
材料与方法
本研究使用了 15 只犬。将金属探针插入第 13 胸椎体。通过将探针冷冻在液氮中，进行 10 分钟的冷冻消融。对照组犬仅插入探针。进行脊髓监测、硬膜外温度测量、运动功能评估和脊髓病理检查。
结果
在 10 分钟的冷冻消融过程中，硬膜外温度下降，并在冷冻消融结束时达到最低硬膜外温度（LET）。每只犬的 LET（摄氏度[°C]）分别为-37、-30、-27、-8、-3、-2、0、1、4、8、16、18、20 和 25。随着硬膜外温度的降低，波形幅度也降低。在冷冻消融结束时（冷冻消融开始后 10 分钟），92.9%（13/14）的犬出现异常波。随着硬膜外复温，波形幅度趋于恢复。在硬膜外复温后（冷冻消融开始后 2 小时），4 只犬（14 只中的 28.6%）出现异常波。硬膜外复温后出现异常波的犬的 LET（°C）分别为-37、-30、-27 和-8。硬膜外复温后无异常波的犬均无运动功能障碍。相比之下，所有硬膜外复温后仍有异常波的犬均有运动功能障碍。在病理评估中，-37、-30、-27、-8、0 和 1 的 LET（°C）的犬发现了低温变化。LET（°C）≥4°C 的犬没有证据表明存在低温性脊髓损伤。低温性脊髓损伤的硬膜外温度阈值为 1 至 4°C，提示硬膜外温度应保持在至少 4°C 以上，以防止低温性脊髓损伤。
Zotero 插件