精神分裂症患者完成言语流畅性任务时前额叶脑血流变化

Changes of homodynamic features in prefrontal cortex of patients with schizophrenia in verbal fluency task

目的:采用近红外光成像技术探讨精神分裂症患者言语流畅性任务时波谱特点及其额叶激活状态。方法:选取符合美国精神障碍诊断与统计手册第4版(DSM-IV)诊断标准的精神分裂症患者99例、正常对照98例,利用近红外光成像仪(NIRS)检测其完成言语流畅性任务时额叶血流的变化。被试会依次听到3个简单的字,然后以这个字为首组成词语或成语。比较精神分裂症组和正常对照组在基线和任务期间的氧合血红蛋白和脱氧血红蛋白的浓度变化。结果:在基线状态时,精神分裂症组的氧合血红蛋白和还原血红蛋白的水平与正常对照组在额叶差异无统计学意义。言语流畅性任务期间,精神分裂症组的氧合血红蛋白平均峰值低于正常对照组[(0.19±0.02)mVmm vs.(0.34±0.03)mVmm,P<0.05],氧合血红蛋白浓度达到峰值的时间明显延迟[(76.5±2.4)s vs.(44.7±2.1)s,P<0.05]。在还原血红蛋白的波谱中,正常对照组的波形一直下降到基线然后上升,而精神分裂症组的波形在10 s时迅速上升到峰值,然后下降后再上升。结论:精神分裂症患者的NIRS检测波谱变化与正常对照不一致,可作为精神分裂症辅助诊断的一个客观指标。

Objective：To investigate the homodynamic features of prefrontal cortex in response to verbal fluency test （VFT） w ith functional near-infrared spectroscope （NIRS） in patients w ith schizophrenia. Methods： Test of NIRS （Hitachi ETG-4000） w as applied to 98 patients w ith schizophrenia meeting the diagnose criteria of Diagnostic and Statistical Manual of Mental Disorders （DSM-IV） and 99 normal controls. All subjects completed verbal fluency test in w hich they w ere asked to make w ords as many as possible according to one of three w ords. The level of oxygenate hemoglobin （Oxy-Hb） and deoxygenate hemoglobin （Deoxy-Hb） w as analyzed in patients w ith schizophrenia and normal control w hen they completed baseline and verbal fluency test. Results： The average value of Oxy-Hb and Deoxy-Hb in patients w ith schizophrenia w as the same as normal controls at baseline. How ever,in the task of VFT,the peak value of Oxy-Hb w as significantly smaller in patients w ith schizophrenia than in normal controls [ （0. 19 ± 0. 02） mVmm vs. （0. 34 ± 0. 03） mVmm,P〈 0. 05],and the time to the peak w as much longer in patients w ith schizophrenia than in normal controls [ （76. 5 ± 2. 4） ms vs. （44. 7 ± 2. 1） ms,P 〈 0. 05]. The spectrum of Deoxy-Hb w as also different in patients w ith schizophrenia and normal controls. In normal controls, the changing trend of spectrum w as going dow n to the baseline and then up,but changing trend of spectrum in schizophrenia w as going up to the pitch in 10 seconds and dow n and then up. Conclusion： It suggests that the character of NIRS in patients w ith schizophrenia is significantly different from that in the normals. The homodynamic features may be a objective assistant diagnostic index in schizophrenia.