多发性硬化患者不同空间频率图形视觉诱发电位分析

Analysis of Pattern Visual Evoked Potential in Patients with Multiple Sclerosis

目的比较多发性硬化症(MS)患者不同空间频率下的图形视觉诱发电位(P-VEP)与正常者是否有差别。方法将2011年9月-2012年4月就诊并确诊为MS患者18例(36只眼)及正常志愿者20例(40只眼)分别进行高(15′)、低(60′)空间频率下P-VEP检查,比较在2种不同空间频率下两组之间的差异。结果 MS患者P-VEP在高空间频率下P100波潜伏时为(120.50±13.04)ms,比正常者(109.21±5.38)ms延迟(P<0.05),在低空间频率下P100波潜伏时为(109.57±12.87)ms,比正常者(103.31±5.45)ms延迟(P<0.05)。MS患者在高空间频率下P100波振幅为(9.17±5.69)μV,比正常者(15.69±8.45)μV降低(P<0.05),在低空间频率下P100波振幅为(11.93±16.75)μV,与正常者振幅(13.47±9.24)μV相比差异无统计学意义(P>0.05)。将MS患者组按照矫正视力的不同分为视力≥1.0组和<1.0组,其中矫正视力≥1.0组在高空间频率下潜伏时为(113.43±8.28)ms,振幅为(12.94±5.46)μV;低空间频率下潜伏时为(111.13±11.50)ms,振幅为(11.57±5.60)μV。矫正视力<1.0组在高空间频率下潜伏时为(126.69±13.49)ms,振幅为(5.87±3.43)μV;低空间频率下潜伏时为(108.26±14.11)ms,振幅为(12.24±5.82)μV。矫正视力不同的两组在低空间频率下潜伏时和振幅之间差异无统计学意义(P>0.05)。结论与正常者相比,MS患者的P-VEP表现为潜伏时的延迟及振幅的降低,其中高空间频率下的视觉诱发电位更为敏感。在临床应用中,高空间频率下的视觉诱发电位可能能作为评价MS患者视功能的重要依据。

Objective To study whether the pattern visual evoked potential （P-VEP） under different spatial frequency in patients with multiple sclerosis （MS） is different from normal people. Methods P-VEP examination under high （15＇） and low （60＇） spatial frequency was performed on 18 MS patients （36 eyes） treated in our department from September 2011 to April 2012 and 20 normal volunteers （40 eyes）. Then, we analyzed the difference between the two groups under the above-mentioned two kinds of spatial frequency. Results The latency of P100 of P-VEP under high spatial frequency in MS patients was （120.50±13.04） ms which was significantly different from （109.21±5.38） ms of normal volunteers （P 〈 0.05）. The latency of P100 of P-VEP under low spatial frequency in MS patients was （109.57±12.87） ms, which was also significantly different from （103.31±_5.45） ms of normal volunteers （P 〈 0.05）. The amplitude of P100 of P-VEP under high spatial frequency in MS patients was （9.17±5.69）μV and it was significantly lower than that [（15.69±8.45）μv] of normal volunteers （P 〈 0.05）. The amplitude of P100 of P-VEP under low spatial frequency in MS patients was （11.93 ± 16.75） μV and it was not significantly different from normal volunteers [ （13.47 ±9.24 μV） ]. Based o n different corrected vision, the MS patients were divided into two groups （vision ≥ 1.0 and vision 〈 1.0）. For patients with vision≥ 1.0, the latency of P 100 and the amplitude of P 100 of P-VEP under high spatial frequency was （113.43±8.28）ms and （12.94±5.46） μV; the latency of Pl00 and the amplitude of P100 of P-VEP under low spatial frequency was （111.13±11.50） ms and （11.57±5.60） μV. For patients with vision 〈 1.0, the latency of P100 and the amplitude of P100 of P-VEP under high spatial frequency was （126.69±13.49） ms and （5.87±3.43） μV; the latency of P100 and the amplitude of P100 of P-VEP under low spatial frequency was （108.26±14.11） ms and （12.24±5.82） μV. There was no significant difference in the latency and amplitude of P100 under low spatial frequency between the two groups with different corrected vision （P 〉 0.05）, but the latency and amplitude of P100 under high spatial frequency were both significantly different between those two groups （P 〈 0.05）. Conclusions Compared with normal people, MS patients feature latency delay and amplitude reduction of the P-VEP, which was more severe under high spatial frequency. P-VEP under high spatial frequency may become an important evidence to evaluate visual function of MS patients.