Counsell Serena J, Edwards A David, Chew Andrew T M, Anjari Mustafa, Dyet Leigh E, Srinivasan Latha, Boardman James P, Allsop Joanna M, Hajnal Joseph V, Rutherford Mary A, Cowan Frances M
Imaging Sciences Department, Robert Steiner MR Unit, Imperial College London, Hammersmith Hospital, London, UK.
Brain. 2008 Dec;131(Pt 12):3201-8. doi: 10.1093/brain/awn268. Epub 2008 Oct 24.
Survivors of preterm birth have a high incidence of neurodevelopmental impairment which is not explained by currently understood brain abnormalities. The aim of this study was to test the hypothesis that the neurodevelopmental abilities of 2-year-old children who were born preterm and who had no evidence of focal abnormality on conventional MR imaging were consistently linearly related to specific local changes in white matter microstructure. We studied 33 children, born at a median (range) gestational age of 28(+5) (24(+4)-32(+1)) weeks. The children were recruited as infants from the Neonatal Intensive Care Unit at Queen Charlotte's and Hammersmith Hospital in the early neonatal period and imaged at a median corrected age of 25.5 (24-27) months. The children underwent diffusion tensor imaging to measure fractional anisotropy (FA) as a measure of tissue microstructure, and neurodevelopmental assessment using the Griffiths Mental Development Scales [giving an overall developmental quotient (DQ) and sub-quotients scores for motor, personal-social, hearing-language, eye-hand coordination and performance scales] at 2 years corrected age. Tract-based spatial statistics with linear regression analysis of voxel-wise cross-subject statistics were used to assess the relationship between FA and DQ/sub-quotient scores and results confirmed by reduced major axis regression of regions with significant correlations. We found that DQ was linearly related to FA values in parts of the corpus callosum; performance sub-scores to FA values in the corpus callosum and right cingulum; and eye-hand coordination sub-scores to FA values in the cingulum, fornix, anterior commissure, corpus callosum and right uncinate fasciculus. This study shows that specific neurodevelopmental impairments in infants born preterm are precisely related to microstructural abnormalities in particular regions of cerebral white matter which are consistent between individuals. FA may aid prognostication and provide a biomarker for therapeutic or mechanistic studies of preterm brain injury.
早产幸存者神经发育障碍的发生率很高，而目前已知的脑部异常并不能解释这一现象。本研究的目的是检验以下假设：早产且在传统磁共振成像上无局灶性异常证据的2岁儿童的神经发育能力与白质微观结构的特定局部变化始终呈线性相关。我们研究了33名儿童，其出生时的中位（范围）胎龄为28（+5）（24（+4）-32（+1））周。这些儿童在新生儿早期从夏洛特女王医院和哈默史密斯医院的新生儿重症监护病房招募为婴儿，并在中位校正年龄25.5（24-27）个月时进行成像。这些儿童接受了扩散张量成像，以测量分数各向异性（FA）作为组织微观结构的指标，并在2岁校正年龄时使用格里菲斯心理发展量表进行神经发育评估[给出总体发育商（DQ）以及运动、个人社交、听力语言、眼手协调和操作量表的子商分数]。使用基于体素的空间统计和体素水平跨受试者统计的线性回归分析来评估FA与DQ/子商分数之间的关系，并通过对具有显著相关性的区域进行主轴回归来确认结果。我们发现，DQ与胼胝体部分的FA值呈线性相关；操作子分数与胼胝体和右侧扣带的FA值相关；眼手协调子分数与扣带、穹窿、前连合、胼胝体和右侧钩束的FA值相关。这项研究表明，早产婴儿的特定神经发育障碍与脑白质特定区域的微观结构异常密切相关，且个体之间具有一致性。FA可能有助于预后评估，并为早产脑损伤的治疗或机制研究提供生物标志物。
