Abstract：
OBJECTIVE: To demonstrate the utility of intraoperative neuromonitoring (IONM) as an effective method of passive thermoprotection against cryogenic injury to neural structures during musculoskeletal and lymph node cryoablation.
METHODS: Twenty-nine patients (16 men; mean age among men, 68.6 years [range, 45-90 years]; mean age among women, 62.6 years [range, 28-88 years]) underwent 33 cryoablations of musculoskeletal and lymph node lesions. Transcranial electrical motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SSEPs) of target nerves were recorded throughout the ablations. Significant change was defined as waveform amplitude reduction greater than 30% (MEP) and 50% (SSEP). The primary outcomes of this study were immediate postprocedural neurologic deficits and frequency of significant MEP and SSEP amplitude reductions.
RESULTS: Significant amplitude reductions were detected in 54.5% (18/33) of MEP tracings and 0% (0/33) of SSEP tracings. Following each occurrence of significant amplitude reductions, freeze cycles were promptly terminated. Intraprocedurally, 13 patients had full recovery of amplitudes to baseline, 11 of whom had additional freeze cycles completed. In 5 of 33 (15.2%) cryoablations, there were immediate postprocedural neurologic deficits (moderate adverse events). Unrecovered MEPs conferred a relative risk for neurologic sequela of 23.2 (95% CI, 3.22-167.21; P < .001) versus those with recovered MEPs. All 5 patients had complete neurologic recovery by 12 months.
CONCLUSIONS: IONM (with MEP but not SSEP) is a reliable and safe method of passive thermoprotection of neurologic structures during cryoablation. It provides early detection of changes in nerve conduction, which when addressed quickly, may result in complete restoration of MEP signals within the procedure and minimize risk of cryogenic neural injury.
METHODS: Twenty-nine patients (16 men; mean age among men, 68.6 years [range, 45-90 years]; mean age among women, 62.6 years [range, 28-88 years]) underwent 33 cryoablations of musculoskeletal and lymph node lesions. Transcranial electrical motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SSEPs) of target nerves were recorded throughout the ablations. Significant change was defined as waveform amplitude reduction greater than 30% (MEP) and 50% (SSEP). The primary outcomes of this study were immediate postprocedural neurologic deficits and frequency of significant MEP and SSEP amplitude reductions.
RESULTS: Significant amplitude reductions were detected in 54.5% (18/33) of MEP tracings and 0% (0/33) of SSEP tracings. Following each occurrence of significant amplitude reductions, freeze cycles were promptly terminated. Intraprocedurally, 13 patients had full recovery of amplitudes to baseline, 11 of whom had additional freeze cycles completed. In 5 of 33 (15.2%) cryoablations, there were immediate postprocedural neurologic deficits (moderate adverse events). Unrecovered MEPs conferred a relative risk for neurologic sequela of 23.2 (95% CI, 3.22-167.21; P < .001) versus those with recovered MEPs. All 5 patients had complete neurologic recovery by 12 months.
CONCLUSIONS: IONM (with MEP but not SSEP) is a reliable and safe method of passive thermoprotection of neurologic structures during cryoablation. It provides early detection of changes in nerve conduction, which when addressed quickly, may result in complete restoration of MEP signals within the procedure and minimize risk of cryogenic neural injury.
摘要：
目的：为了证明术中神经监测（IONM）作为一种有效的被动热保护方法，可防止肌肉骨骼和淋巴结冷冻消融过程中神经结构的低温损伤。
方法：29例患者（16例男性，平均年龄和范围，M：68.6和45-90，F：62.6和28-88）进行了33次肌肉骨骼和淋巴结病变的冷冻消融。在整个消融过程中记录目标神经的经颅电运动诱发电位（MEP）和体感诱发电位（SSEP）。显著变化定义为波形振幅降低大于30%(MEP)和50%(SSEP)。这项研究的主要结果是术后即刻的神经功能缺损以及MEP和SSEP振幅显着降低的频率。
结果：在MEP描记的54.5％（18/33）和SSEP描记的0％（0/33）中检测到幅度显着降低。每次出现明显的振幅降低后，冻结周期迅速终止。在程序内部，13例患者的振幅完全恢复至基线，其中11个完成了额外的冻结周期。在5/33(15.2%)的冷冻消融中，术后即刻出现神经功能缺损(中度不良事件).未恢复的MEP使神经系统后遗症的相对风险为23.2(95%置信区间[CI]，3.22-167.21;P=0.0009)vs.那些有恢复的欧洲议会议员。到12个月时，所有5名患者的神经系统均完全恢复。
结论：IONM是一种可靠的，冷冻消融过程中神经结构被动热保护的安全方法。它提供神经传导变化的早期检测，当很快解决时，可能导致MEP信号在手术中完全恢复，并将低温神经损伤的风险降至最低。
方法：29例患者（16例男性，平均年龄和范围，M：68.6和45-90，F：62.6和28-88）进行了33次肌肉骨骼和淋巴结病变的冷冻消融。在整个消融过程中记录目标神经的经颅电运动诱发电位（MEP）和体感诱发电位（SSEP）。显著变化定义为波形振幅降低大于30%(MEP)和50%(SSEP)。这项研究的主要结果是术后即刻的神经功能缺损以及MEP和SSEP振幅显着降低的频率。
结果：在MEP描记的54.5％（18/33）和SSEP描记的0％（0/33）中检测到幅度显着降低。每次出现明显的振幅降低后，冻结周期迅速终止。在程序内部，13例患者的振幅完全恢复至基线，其中11个完成了额外的冻结周期。在5/33(15.2%)的冷冻消融中，术后即刻出现神经功能缺损(中度不良事件).未恢复的MEP使神经系统后遗症的相对风险为23.2(95%置信区间[CI]，3.22-167.21;P=0.0009)vs.那些有恢复的欧洲议会议员。到12个月时，所有5名患者的神经系统均完全恢复。
结论：IONM是一种可靠的，冷冻消融过程中神经结构被动热保护的安全方法。它提供神经传导变化的早期检测，当很快解决时，可能导致MEP信号在手术中完全恢复，并将低温神经损伤的风险降至最低。
