Abstract：
OBJECTIVE: Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a genetic disorder resulting in abnormal regulation of γ-aminobutyric acid, lipid metabolism, and myelin biogenesis, leading to ataxia, seizures, and cognitive impairment. Since the myelin sheath is thinner in a murine model of SSADHD compared to a wild type, we hypothesized that this also holds for human brain. We tested whether the conduction velocity in the somatosensory pathway is accordingly delayed.
METHODS: Somatosensory evoked magnetic fields (SEF) produced by transcutaneous electrical stimulation of the median nerve were measured in 13 SSADHD patients, 11 healthy and 14 disease controls with focal epilepsy. The peak latencies of the initial four components (M1, M2, M3 and M4) were measured.
RESULTS: The SEF waveforms and scalp topographies were comparable across the groups. The latencies were statistically significantly longer in the SSADHD group compared to the two controls. We found these latencies for the SSADHD, healthy and disease controls respectively to be: M1: (21.9 ± 0.8 ms [mean ± standard error of the mean], 20.4 ± 0.6 ms, and 21.0 ± 0.4 ms) (p < 0.05); M2: (36.1 ± 1.0 ms, 33.1 ± 0.6 ms, and 32.1 ± 1.1 ms) (p < 0.005); M3: (62.5 ± 2.4 ms, 54.7 ± 2.0 ms, and 49.9 ± 1.8 ms) (p < 0.005); M4: (86.2 ± 2.3 ms, 78.8 ± 2.8 ms, and 73.5 ± 2.9 ms) (p < 0.005).
CONCLUSIONS: The SEF latencies are delayed in patients with SSADHD compared with healthy controls and disease controls.
CONCLUSIONS: This is the first study that compares conduction velocities in the somatosensory pathway in SSADHD, an inherited disorder of GABA metabolism. The longer peak latency implying slower conduction velocity supports the hypothesis that myelin sheath thickness is decreased in SSADHD.
METHODS: Somatosensory evoked magnetic fields (SEF) produced by transcutaneous electrical stimulation of the median nerve were measured in 13 SSADHD patients, 11 healthy and 14 disease controls with focal epilepsy. The peak latencies of the initial four components (M1, M2, M3 and M4) were measured.
RESULTS: The SEF waveforms and scalp topographies were comparable across the groups. The latencies were statistically significantly longer in the SSADHD group compared to the two controls. We found these latencies for the SSADHD, healthy and disease controls respectively to be: M1: (21.9 ± 0.8 ms [mean ± standard error of the mean], 20.4 ± 0.6 ms, and 21.0 ± 0.4 ms) (p < 0.05); M2: (36.1 ± 1.0 ms, 33.1 ± 0.6 ms, and 32.1 ± 1.1 ms) (p < 0.005); M3: (62.5 ± 2.4 ms, 54.7 ± 2.0 ms, and 49.9 ± 1.8 ms) (p < 0.005); M4: (86.2 ± 2.3 ms, 78.8 ± 2.8 ms, and 73.5 ± 2.9 ms) (p < 0.005).
CONCLUSIONS: The SEF latencies are delayed in patients with SSADHD compared with healthy controls and disease controls.
CONCLUSIONS: This is the first study that compares conduction velocities in the somatosensory pathway in SSADHD, an inherited disorder of GABA metabolism. The longer peak latency implying slower conduction velocity supports the hypothesis that myelin sheath thickness is decreased in SSADHD.
摘要：
目的：琥珀酸半醛脱氢酶缺乏症（SSADHD）是一种导致γ-氨基丁酸调节异常的遗传性疾病，脂质代谢，和髓鞘生物发生，导致共济失调,癫痫发作,和认知障碍。由于与野生型相比，SSADHD的鼠模型中的髓鞘更薄，我们假设这也适用于人类大脑。我们测试了体感通路中的传导速度是否相应地延迟。
方法：在13例SSADHD患者中测量了经皮电刺激正中神经产生的体感诱发磁场（SEF），11个健康和14个患有局灶性癫痫的疾病对照。测量初始四种组分(M1、M2、M3和M4)的峰潜伏期。
结果：各组的SEF波形和头皮形貌具有可比性。与两个对照相比，SSADHD组的潜伏期在统计学上显着更长。我们发现了SSADHD的这些延迟，健康和疾病对照分别为：M1：（21.9±0.8ms[平均值±平均值的标准误差]，20.4±0.6ms，和21.0±0.4ms（p<0.05）；M2：（36.1±1.0ms，33.1±0.6ms,和32.1±1.1ms）（p<0.005）；M3：（62.5±2.4ms，54.7±2.0ms,49.9±1.8ms(p<0.005);M4:(86.2±2.3ms,78.8±2.8ms，和73.5±2.9ms(p<0.005)。
结论：与健康对照组和疾病对照组相比，SSADHD患者的SEF潜伏期延迟。
结论：这是第一项比较SSADHD体感通路传导速度的研究，GABA代谢的遗传性疾病。较长的峰值潜伏期意味着较慢的传导速度支持SSADHD中髓鞘厚度减少的假设。
方法：在13例SSADHD患者中测量了经皮电刺激正中神经产生的体感诱发磁场（SEF），11个健康和14个患有局灶性癫痫的疾病对照。测量初始四种组分(M1、M2、M3和M4)的峰潜伏期。
结果：各组的SEF波形和头皮形貌具有可比性。与两个对照相比，SSADHD组的潜伏期在统计学上显着更长。我们发现了SSADHD的这些延迟，健康和疾病对照分别为：M1：（21.9±0.8ms[平均值±平均值的标准误差]，20.4±0.6ms，和21.0±0.4ms（p<0.05）；M2：（36.1±1.0ms，33.1±0.6ms,和32.1±1.1ms）（p<0.005）；M3：（62.5±2.4ms，54.7±2.0ms,49.9±1.8ms(p<0.005);M4:(86.2±2.3ms,78.8±2.8ms，和73.5±2.9ms(p<0.005)。
结论：与健康对照组和疾病对照组相比，SSADHD患者的SEF潜伏期延迟。
结论：这是第一项比较SSADHD体感通路传导速度的研究，GABA代谢的遗传性疾病。较长的峰值潜伏期意味着较慢的传导速度支持SSADHD中髓鞘厚度减少的假设。
