Guy's and St. Thomas' NHS Foundation Trust, London, UK.
South Infirmary Victoria University Hospital, Cork, Ireland.
Pain Pract. 2024 Feb;24(2):270-277. doi: 10.1111/papr.13301. Epub 2023 Oct 14.
Advances in Spinal cord stimulation (SCS) device technology in recent years have led to the development of SCS systems that are magnetic resonance imaging (MRI)-conditional, most of which are dependent on normal lead impedances. The objective of this study was to retrospectively analyze the rate of elevated lead impedance in these devices to determine the rate of failure of MR-conditional modes.
This was a single-center, retrospective, chart-based review conducted during a five-year period. Patients were included if they had been implanted with an impedance-dependent MR-conditional SCS and had a documented impedance check at least 6 months after implantation. A Kaplan-Meier survival analysis was performed to map the survival of MR-conditionality over time.
There were 363 cases included between 2015 and 2020, which corresponded to a total of 602 SCS leads. Nevro was the most common manufacturer (67.8%), followed by Boston Scientific (22.3%) and Abbott (9.9%). The average overall follow-up time was 2.25 years. Overall, 67 (18.5%) of patients had lead impedances over 10,000 Ω at follow-up with a total of 186 electrode contacts (3.9%). Leads most commonly had either one (40%), two (22%) or three (12%) electrode contacts out of range. Risk of failure of lead impedances increased by 35.4% with each successive year to a peak of 43% of all leads by year 5. Mean overall survival time of normal lead impedances was 4.77 years (CI 4.40-5.13). There was no statistically significant difference in mean overall survival time between Abbott (M = 4.0 years, SD = 1.25), Boston Scientific (M = 4.64 years, SD = 1.75) and Nevro (M = 4.80 years, SD = 3.28), χ (2, N = 358) = 1.511, p = 0.47; however, Abbott leads had a greater total number of failed impedance contacts (50/568, 8.8%), in comparison to Nevro (124/3064, 4.0%), χ (1, N = 3630) = 23.76, p < 0.00001, at a similar follow-up time.
This retrospective study identified elevated impedances in 18.5% of MR-conditional SCS devices at an average of 2.25 years follow-up resulting in loss of MR-conditionality and a mean overall lead survival time of 4.77 years for normal lead impedance.
近年来，脊髓刺激（SCS）设备技术的进步导致了磁共振成像（MRI）条件下的 SCS 系统的发展，其中大多数依赖于正常的导联阻抗。本研究的目的是回顾性分析这些设备中升高的导联阻抗率，以确定 MRI 条件模式故障的发生率。
这是一项在五年期间进行的单中心、回顾性、基于图表的研究。如果患者植入了依赖于阻抗的 MRI 条件 SCS 并在植入后至少 6 个月进行了阻抗检查，则将其纳入研究。使用 Kaplan-Meier 生存分析绘制随时间推移的 MRI 条件的生存曲线。
在 2015 年至 2020 年期间，共纳入 363 例患者，共涉及 602 个 SCS 导联。Nevro 是最常见的制造商（67.8%），其次是 Boston Scientific（22.3%）和 Abbott（9.9%）。平均总随访时间为 2.25 年。总体而言，67 名（18.5%）患者在随访时的导联阻抗超过 10000 Ω，共有 186 个电极触点（3.9%）。导联最常见的情况是一个（40%）、两个（22%）或三个（12%）电极触点超出范围。每个连续年度，导联阻抗故障的风险增加 35.4%，到第 5 年时达到所有导联的峰值 43%。正常导联阻抗的平均总生存时间为 4.77 年（CI 4.40-5.13）。Abbott（M=4.0 年，SD=1.25）、Boston Scientific（M=4.64 年，SD=1.75）和 Nevro（M=4.80 年，SD=3.28）之间的平均总生存时间无统计学差异， χ （2，N=358）=1.511，p=0.47；然而，Abbott 导联的阻抗失效电极触点总数（50/568，8.8%）高于 Nevro（124/3064，4.0%）， χ （1，N=3630）=23.76，p<0.00001，随访时间相似。
这项回顾性研究在平均 2.25 年的随访中发现 18.5%的 MRI 条件 SCS 设备存在升高的阻抗，导致 MRI 条件丧失，正常导联阻抗的平均总导联生存时间为 4.77 年。
