Maalouf E F, Duggan P J, Rutherford M A, Counsell S J, Fletcher A M, Battin M, Cowan F, Edwards A D
Department of Paediatrics and The Robert Steiner MR Unit and MRC Clinical Science Centre, Imperial College School of Medicine, Hammersmith Hospital, Du Cane Road, London, England.
J Pediatr. 1999 Sep;135(3):351-7. doi: 10.1016/s0022-3476(99)70133-2.
To define magnetic resonance imaging (MRI) appearances of the brain in extremely preterm infants between birth and term, a sequential cohort of infants born at a gestational age <30 weeks was studied with a dedicated neonatal magnetic resonance scanner. Images of infants (n = 41) with a median gestational age of 27 weeks (range 23 to 29 weeks) were initially obtained at a median age of 2 days (range 1 to 20 days) and then repeatedly studied; 29 (71%) infants had MRI at a median gestational age of 43 weeks (range 38 to 52 weeks) (term MRI). On the initial MRI scan 28 of 41 infants had abnormalities: either intraventricular hemorrhage, germinal layer hemorrhage, ventricular dilatation, or diffuse and excessive high signal intensity in the white matter on T(2)-weighted images. When magnetic resonance images for preterm infants at term gestation were compared with those of infants in the control group born at term, 22 of 29 infants had dilatation of the lateral ventricles, 24 of 29 had squaring of the anterior or posterior horns of the lateral ventricles, 11 of 29 had a widened interhemispheric fissure or extracerebral space, and 22 of 29 had diffuse and excessive high signal intensity in the white matter. There were no cases of cystic periventricular leukomalacia. We conclude that MRI abnormalities are commonly seen in the brain of preterm infants on whom images are obtained within 48 hours of birth and that further abnormalities develop between birth and term. A characteristic appearance of diffuse and excessive high signal intensity in the white matter on T(2)-weighted images is associated with the development of cerebral atrophy and may be a sign of white matter disease. These MRI appearances may help account for the high incidence of neurodevelopmental impairment in extremely preterm infants.
为明确极早产儿从出生到足月时脑的磁共振成像（MRI）表现，我们使用一台专用的新生儿磁共振扫描仪对一组孕周＜30周的连续队列婴儿进行了研究。对中位孕周为27周（范围23至29周）的41例婴儿，最初在中位年龄2天（范围1至20天）时获取图像，随后进行多次研究；29例（71%）婴儿在中位孕周43周（范围38至52周）时进行了MRI检查（足月MRI）。在初次MRI扫描时，41例婴儿中有28例存在异常：脑室内出血、生发层出血、脑室扩张或T2加权图像上白质弥漫性高信号强度增加。将足月妊娠早产儿的磁共振图像与足月出生的对照组婴儿的图像进行比较时，29例婴儿中有22例侧脑室扩张，29例中有24例侧脑室前角或后角呈方形，29例中有11例半球间裂或脑外间隙增宽，29例中有22例白质弥漫性高信号强度增加。没有脑室周围白质软化囊性变的病例。我们得出结论，出生后48小时内进行图像检查的早产儿脑中MRI异常常见，且出生至足月期间会出现更多异常。T2加权图像上白质弥漫性高信号强度增加这一特征性表现与脑萎缩的发生有关，可能是白质疾病的一个征象。这些MRI表现可能有助于解释极早产儿神经发育障碍的高发生率。
