利用高分辨MR技术观测感音性聋儿前庭蜗神经改变及其与年龄的关系

Application of high- resolution MR on vestibular cochlear nerve examination in children with sensorineural deafness

【目的】探讨先天性感音神经性耳聋(congenital sensorineural hearing loss,CSNHL)患儿的前庭蜗神经(vestibulocochlear nerve,VCN)发育与年龄的关系。【方法】应用高分辨MR技术对CSNHL患儿的双侧内耳形态及VCN进行观察、测量。应用德国Siemens公司Magnetom Trio Tim MR 3.0T扫描仪对43例CSNHL患儿及12例听力正常对照者进行全脑的常规T1WI、T2WI扫描,并对耳部进行高分辨扫描。T2-SPACE参数为:TR/TE 1 000/132 ms/ms,矩阵200×200。测量所有研究对象双侧VCN的水平径、横截面积及横截面周长。每一个患者都有临床、影像和听力测验的资料。【结果】(1)CSNHL组及正常对照组左、右侧VCN横径(CSNHL:0.140,0.195;NC:0.12,0.115)、横截面积(CSNHL:0.029,0.029;NC:0.044,0.053)及横截面周长(CSNHL:0.683,0.70;NC:0.811,0.811)分别比较,均无统计学差异(P>0.05)。(2)VCN横径、横截面积及横截面周长在内耳结构正常组患儿(Ⅰ组)(R:0.095,0.029,0.708)、内耳结构异常组患儿(Ⅱ组)(R:0.097,0.028,0.688)与正常对照组(Ⅲ组)(R:0.115,0.053,0.945)方差分析,且存在统计学差异(P<0.05)。(3)带助听器患儿组(甲组)(R:0.096,0.030,0.696)、不带助听器患儿组(乙组)(R:0.094,0.028,0.705)及正常对照组(R:0.115,0.053,0.945)VCN横径、横截面积及横截面周长比较,甲组、乙组左侧VCN横截面积及周长、右侧VCN横径、横截面积及周长小于丙组(P<0.05)。(4)正常对照组的VCN的横截面积和周长都随着年龄的增长而增大(P<0.001),而CSNHL患儿的VCN横截面积和周长和年龄无明显的线性关系。【结论】内耳结构可能会影响VCN的发育。CSNHL患儿的VCN大小与年龄无明显线性关系。MRI内耳水成像能清晰显示是人工耳蜗植入术前必要的影像学检查。

【Objective】To explore the relationship between development of vestibulocochlear nerve（VCN） and age in children with congenital sensorineural hearing loss（CSNHL）.【Methods】The inner ear configuration and VCN of both sides in children with CSNHL were observed and measured with high resolution MRI. Conventional T1 WI and T2 WI scan of whole brain and ear high-resolution scan were carried on with Magnetom Trio Tim MRI 3.0T scanner（German Siemens company） in 43 cases with CSNHL and 12 children with normal hearing. The parameters of T2-SPACE were as follows： TR/TE 1000/132 ms/ms, matrix of 200×200. VCN diameter, cross-sectional area and the cross-sectional circumference in both sides of all subjects were measured. Clinical data, as well as imaging and hearing-test results were available in each patient.【Results】（1） There was no significant difference in left and right VCN diameter（CSNHL：0.140,0.195;NC：0.12,0.115）, cross- sectional area（CSNHL：0.029,0.029;NC：0.044,0.053）and cross- sectional circumference（CSNHL：0.683,0.70;NC：0.811,0.811） of CSNHL group and normal control group（P〉0.05）.（2） VCN diameter, cross- sectional area and crosssectional perimeter of children in normal inner ear structure group（Ⅰ）（R：0.095,0.029,0.708）, structural abnormal inner ear structure group（Ⅱ group）（R：0.097,0.028,0.688） and normal control group（Ⅲ group）（R：0.115,0.053,0.945）made significant difference via analysis of variance（P〈0.05）.（3） VCN diameter, cross-sectional area and cross-sectional circumference in group A（children with hearing aid）, group B（children without hearing aid） and group C（normal control） were as follows：（R：0.096,0.030,0.696）,（R：0.094,0.028,0.705）,（R：0.115,0.053,0.945）. Right VCN diameter, left and right VCN cross-sectional area and perimeter in group B and all in group A were less than those in group C（P〈0.05）.（4） VCN cross-sectional area and perimeter in normal control group increased with age（P〈0.001）.However, VCN cross-sectional area and perimeter of CSNHL children had no significant linear relationship with age. 【Conclusion】This study found that children have changed CSNHL VCN size smaller than normal. This means that there is bad or atrophy development. Inner ear structure may affect the development of VCN. There is no significant linear relationship between VCN size and age of CSNHL children. Clear inner ear fluid imaging via MRI is a necessary preoperative examination for cochlear implantation.