重度突发性聋患者急性期与恢复期听皮层磁共振波谱分析

目的 利用氢质子磁共振波谱(1H-MRS)技术，研究单侧重度突发性聋患者急性期与恢复过程中听皮层的代谢变化。方法 选取右耳重度突发性聋急性期患者15例(发病时间＜1周)，经过常规治疗3个月后恢复期患者9例,健康志愿者10例作为对照组。将全部受试者行磁共振波谱检测，测定双侧颞横回N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)、γ-氨基丁酸(GABA)、谷氨酰胺及谷氨酸复合物(Glu)的峰下面积并计算NAA/ Cr、Cho/Cr、GABA/ Cr、Glu/Cr的比值。分析重度突聋急性期与3个月后双侧听皮层代谢差异。结果 与对照组相比，突聋急性期双侧NAA/Cr、双侧Cho/Cr，右侧GABA/Cr、右侧Glu/Cr比值无明显差异(P＞0.05)，而左侧听皮层GABA/Cr比值明显下降，Glu/Cr明显上升(P＜0.05)。突聋3个月组双侧NAA/Cr、右侧Cho/Cr、右侧GABA/Cr、右侧Glu/Cr比值无明显差异(P＞0.05)。左侧Cho/Cr比值稍下降，GABA/Cr比值略上升但仍低于对照组，Glu/Cr比值略下降但仍高于对照组(P<0.05)。结论 磁共振波谱可以为人体活体听皮层代谢物浓度改变提供有价值的信息；突聋患者对侧听皮层GABA、Glu代谢异常，提示听觉中枢可能发生代谢改变、功能重组。

1H-MRS study of the auditory cortex in patients with severe sudden sensorineural hearing loss in acute and convalescent stages

Objective To study the metabolic changes of the auditory cortex in the patients with unilateral severe sudden sensorineural hearing loss (SSNHL) in acute and convalescent stages by using proton magnetic resonance spectroscopy (1H-MRS). Methods 15 patients with acute severe SSNHL in right ear were studied (the onset time of severe sudden deafness＜1 week). 9 patients with severe SSNHL, who experienced conventional therapy in the last 3 months, and 10 normal hearing volunteers were checked with proton magnetic resonance spectroscopy. N-acetylaspartic acid (NAA), creatine (Cr), choline (Cho), γ-aminobutyric acid (GABA), glutamine and glutamic acid compound (Glu) were measured. The differences between patients with severe SSNHL in the acute stage and convalescent stage were analyzed. Results There was no significant difference of the bilateral NAA/Cr, bilateral Cho/Cr, right GABA/Cr, and right Glu/Cr ratios in the auditory cortex between severe SSNHL patients in the acute stage and the control group(P＞0.05). The GABA/Cr ratio was significantly lower in the left auditory cortex of severe SSNHL patients in the acute stage than that in the control group(P＜0.05). The Glu/Cr ratio was significantly higher in the left auditory cortex of severe SSNHL patients in the acute stage than that in the control group(P＜0.05). There was no significant difference of the bilateral NAA/Cr, right Cho/Cr, right GABA/Cr and right Glu/Cr ratios in the auditory cortex between severe SSNHL patients in the convalescent stage and the control group(P＞0.05). The Cho/Cr ratio was significantly lower in the left auditory cortex of severe SSNHL patients in the convalescent stage than that in the control group(P＜0.05). The GABA/Cr ratio was slightly increased but still significantly lower in the left auditory cortex of severe SSNHL patients in the convalescent stage than that in the control group(P＜0.05). The Glu/Cr ratio was slightly decreased but still significantly higher in the left auditory cortex of severe SSNHL patients in the convalescent stage than that in the control group(P＜0.05). Conclusion 1H-MRS is a noninvasive technique that can provide useful information concerning metabolic changes of the auditory cortex in humans. The metabolic disturbance of GABA and Glu observed in the contralateral auditory cortex of the deaf ear with unilateral SSNHL indicates the functional reorganization and metabolic changes of the auditory cortex after hearing loss.