单侧感音神经性耳聋患者静息态fMRI观察

Resting-state functional MRI research of the auditory cortex in patients with long-term unilateral hearing loss

目的用静息态fMRI观察单侧感音神经性耳聋患者静息状态下脑功能连接网络的变化。方法入组患者为2011年2月至2012年4月通过广告募集或来自于东南大学附属中大医院耳鼻喉科。耳聋组29例（左耳聋15例，右耳聋14例），患耳聋均为70dBHL以上；匹配的健康对照组左侧15例，右侧14例。用功能连接种子相关方法，观察健康人与耳聋患者的听觉网络的功能连接脑图，并比较其差异。结果耳聋患者听觉皮质的正向连接网络均较健康人变弱。以患侧听觉皮质为种子点时，左、右侧耳聋患者听觉皮质L1分别为30．14，-31．25；而以健侧听觉皮质为种子点时，左、右侧耳聋患者听觉皮质u分别为0．1，19．37。组间分析显示耳聋患者比健康组可见更多激活的脑区，左耳聋患者主要为额叶（双侧中央前回、左侧额中回及左侧额上回）、顶叶（楔前叶）及后扣带回，右耳聋患者比健康人多的脑区位于右侧尾状核。结论静息状态下健侧听觉皮质与患侧听皮质及周围相关脑区连接下降，可能是大脑适应性功能重组的表现。

Objective To evaluate functional connectivity in patients with unilateral sensorineural hearing loss（USNHL） using resting-state fMRI. Methods Functional connectivity MRI were employed in 29 patients with SNHL （ 15 left, 14 right） with averaged hearing level above 70 dB HL for the deaf ear, and matched 15 and 14 normal hearing subjects, respectively, were recruited. Functional connectivity mappings between the SNHL patients and normal hearing subjects were evaluated and the differences were contrasted. Results The positive functional connectivity of auditory cortex with whole brain in USNHL patients is weaker than that in normal subjects both in volume and intensity. Using the affected side A I as a seed, left and right Laterality index （LI） of auditory cortex was 30. 14, - 31.25, respectively. Using the healthy side as a seed, the LI of auditory cortex was 0. 1,19. 37, respectively. Compared to normal subjects, increased activation in bilateral precentral gyrus, left middle frontal gyrus, left superior frontal gyrus and posterior cingulate cortex/precuneus were found in left USNHL patients. Contrasted with normal subjects, no significant difference was found between the normal subjects and right SNHL patients, except the right caudate nucleus using left A I as a seed. Conclusion The reduced functional connectivity among the affected side and healthy side auditory cortex as well as associated auditory cortex may suggest a result of functional reorganization adaptive to the SNHL.