School of Optometry and Vision Sciences, University of Waterloo, Waterloo, ON, Canada.
Department of Ophthalmology, Children's Hospital Los Angeles, Los Angeles, CA, USA.
Doc Ophthalmol. 2021 Oct;143(2):141-153. doi: 10.1007/s10633-021-09830-2. Epub 2021 Mar 29.
Sedation with chloral hydrate or anesthesia using propofol allow ocular examination and testing in young children, but these drugs may affect electrophysiologic recordings. We compared the flash and pattern ERGs and VEPs recorded with each drug in a cohort of young children enrolled in a prospective study of optic nerve hypoplasia (ONH) syndrome.
ERGs and VEPs to light-adapted, standard, full-field flashes, to standard and steady-state pattern-reversal (PR) were recorded with cycloplegia in 9 participants. Age range at the first session, with chloral hydrate was 8-23 mo; at the second session with propofol it was 20-29 mo. Examiners masked to the drug and clinical conditions measured the waveforms for longitudinal, paired comparisons between the sessions.
Flash ERG amplitudes did not differ between sessions; peak times were longer at the second session (propofol) by clinically insignificant amounts (< 2 ms, p = 0.002). Standard PERGs had larger amplitudes and later peaks in the second session (propofol) than with chloral hydrate (P50 2.9 vs 4.7 μV, p = 0.016 and 43 vs 52 ms, p < 0.001; N95 4.0 vs 6.1 μV, p = 0.003 and 91 vs 98.5 ms p = 0.034.). These differences were present for those with an interval of > 10 mo between sessions (n = 5, 10 eyes) but not for those with a shorter inter-test interval (< 8 mo, p > 0.05, n = 4). Magnitudes of the steady-state PERGs did not differ between tests but the waveforms had earlier peaks at the second test with propofol. Flash VEP waveforms were present in 10/18 eyes and showed 72% agreement for recordability between sessions. Standard pattern VEPs were recordable in only a few eyes in this cohort with ONH.
Light-adapted flash ERG waveforms were generally similar with chloral hydrate and with propofol. Larger PERGs with later peaks, found in the second session (propofol) could reflect maturation of the PERG generators, as the differences found were associated with a greater age difference between the sessions, but we do not rule out that small differences in the waveforms may be drug-related. There are insufficient VEP data from these children with ONH to identify drug-related or maturational effects on VEPs.
水合氯醛镇静或依托咪酯麻醉可用于检查和测试幼儿的眼部，但这些药物可能会影响电生理记录。我们比较了在视神经发育不良（ONH）综合征前瞻性研究中入组的一组幼儿中，使用这两种药物记录的闪光和图形视网膜电图（ERG）和视觉诱发电位（VEP）。
9 名参与者在睫状肌麻痹下接受光适应标准全视野闪光、标准和稳态图形翻转（PR）的闪光和图形 ERG 和 VEP 记录。第一次氯醛水合 session 的年龄范围为 8-23 个月；第二次异丙酚 session 的年龄范围为 20-29 个月。在药物和临床状况方面，评估者对记录进行了遮蔽，以对两个 session 之间的纵向、配对比较进行了测量。
闪光 ERG 振幅在两个 session 之间没有差异；第二个 session（异丙酚）的峰值时间延长，但临床意义不大（<2ms，p=0.002）。标准 PERG 在第二个 session（异丙酚）中的振幅更大，峰值更高，与氯醛水合 session 相比（P50 为 2.9μV 对 4.7μV，p=0.016；43ms 对 52ms，p<0.001；N95 为 4.0μV 对 6.1μV，p=0.003；91ms 对 98.5ms，p=0.034）。这些差异在两次测试之间间隔超过 10 个月的参与者（n=5，10 只眼）中存在，但在两次测试间隔小于 8 个月的参与者（p>0.05，n=4）中不存在。稳态 PERG 的幅度在两次测试之间没有差异，但在第二个异丙酚测试中，波形的峰值更早。闪光 VEP 波形在 18 只眼中的 10 只眼中存在，两次 session 之间的记录可重复性为 72%。在这个 ONH 队列中，只有少数眼睛可以记录到标准图形 VEP。
氯醛水合 session 和异丙酚 session 记录的光适应闪光 ERG 波形通常相似。第二个 session（异丙酚）中发现的更大的 PERG 和更晚的峰值可能反映了 PERG 发生器的成熟，因为发现的差异与两次 session 之间的年龄差异较大有关，但我们不能排除波形的微小差异可能与药物有关。这些 ONH 患儿的 VEP 数据不足，无法确定 VEP 与药物相关或与成熟度相关的影响。
