Shibata Dean K, Kwok Edmund
Department of Radiology, University of Washington Medical Center, Seattle, 98195, USA.
Acad Radiol. 2006 Jun;13(6):738-43. doi: 10.1016/j.acra.2006.02.037.
Experimental studies in animals have shown that loss of a primary sensory modality early in life may result in substantial alterations in cortical organization. This study was performed to measure cerebral perfusion in auditory cortex in congenitally deaf adults using the FAIR (Flow-sensitive Alternating Inversion Recovery) magnetic resonance imaging technique. Our hypothesis was that there would be relatively intact perfusion in auditory cortex.
Twenty-six profoundly congenitally deaf subjects were compared with 15 control subjects. A FAIR perfusion slice was scanned through the superior temporal gyrus parallel to the Sylvian fissure while subjects were at rest. Perfusion maps were calculated and regions of interest were drawn over the superior temporal gyrus including auditory cortex and the medial occipital lobe.
The relative perfusion of the superior temporal gyrus (STG) was slightly less in the deaf (right STG = 0 .79 +/- 0.16, left = 0.93 +/- 0.29) compared with the hearing (right STG = 0.90 +/- 0.14, left = 0.98 +/- 0.31) when normalized to the occipital cortex, but the differences were not statistically significant. Both showed moderate left lateralization; however, only in the deaf did this reach statistical significance (P < .01).
In the resting state, the deaf demonstrate a relatively normal perfusion in the region of cortex usually associated with auditory function. Although the presumed underlying electrical activity may represent some degree of residual auditory function, it is likely that the normal level of perfusion reflects cortical reorganization and the early migration of nonauditory processing into this area.
动物实验研究表明，生命早期主要感觉模态的丧失可能导致皮质组织发生显著改变。本研究采用FAIR（流动敏感交替反转恢复）磁共振成像技术，对先天性耳聋成年人听觉皮层的脑灌注进行测量。我们的假设是听觉皮层的灌注相对完整。
将26名先天性深度耳聋受试者与15名对照受试者进行比较。在受试者休息时，通过与外侧裂平行的颞上回扫描FAIR灌注切片。计算灌注图，并在包括听觉皮层和枕叶内侧的颞上回绘制感兴趣区域。
与听力正常者相比，将颞上回（STG）的灌注归一化至枕叶皮层后，耳聋者的相对灌注略低（右侧STG = 0.79 ± 0.16，左侧 = 0.93 ± 0.29），而听力正常者为（右侧STG = 0.90 ± 0.14，左侧 = 0.98 ± 0.31），但差异无统计学意义。两者均显示出中度的左侧化；然而，只有耳聋者达到统计学意义（P <.01）。
在静息状态下，耳聋者在通常与听觉功能相关的皮层区域表现出相对正常的灌注。尽管推测潜在的电活动可能代表某种程度的残余听觉功能，但正常水平的灌注很可能反映了皮质重组以及非听觉处理早期向该区域的迁移。
