Lamont P, Sachinwalla T, Pamphlett R
Department of Pathology, University of Sydney, New South Wales, Australia.
Pediatrics. 1995 Mar;95(3):409-13.
Abnormalities of myelin that have been reported in Sudden Infant Death Syndrome (SIDS) include a delay in development and focal lesions presumed to be secondary to hypoxia. Magnetic resonance imaging (MRI) gives excellent images of white matter and can be used to map the progress of myelination and to demonstrate focal lesions. It was the aim of this study to determine whether any MRI abnormality of myelin could be detected in the brains of SIDS compared to control infants.
The brains of 28 SIDS and 14 control infants were fixed in formalin and scanned with MRI. The proton density, T2-weighted, and inversion recovery scans were assessed for the presence of focal white matter lesions. The amount of myelin in 26 sites was measured in the proton density scans, using a densitometer. The amount of myelin present could be assessed in 21 of 26 sites.
In 15 of 21 sites the amount of myelin for age was the same in SIDS and controls. In three sites the rate of myelination was greater in SIDS than control and in another three sites the amount of myelin for age was greater in SIDS than control infants, but these differences were not seen in infants aged less than 8 months. No focal abnormalities of white matter were seen in either SIDS or control infants.
The development of white matter in brains of SIDS infants less than 8 months old is the same as in controls, and in older SIDS infants white matter development may be slightly advanced compared to controls. No hypoxic changes can be seen in SIDS white matter on MRI.
婴儿猝死综合征（SIDS）中已报道的髓鞘异常包括发育延迟和推测为继发于缺氧的局灶性病变。磁共振成像（MRI）能提供出色的白质图像，可用于描绘髓鞘形成的进程并显示局灶性病变。本研究的目的是确定与对照婴儿相比，SIDS婴儿脑内是否能检测到任何髓鞘的MRI异常。
将28例SIDS婴儿和14例对照婴儿的脑用福尔马林固定并进行MRI扫描。评估质子密度、T2加权和反转恢复扫描以确定是否存在局灶性白质病变。在质子密度扫描中，使用密度计测量26个部位的髓鞘量。26个部位中有21个部位的髓鞘量可进行评估。
在21个部位中的15个部位，SIDS婴儿和对照婴儿的髓鞘年龄量相同。在3个部位，SIDS婴儿的髓鞘形成速率高于对照婴儿，在另外3个部位，SIDS婴儿的髓鞘年龄量大于对照婴儿，但在8个月以下的婴儿中未观察到这些差异。SIDS婴儿和对照婴儿均未发现白质的局灶性异常。
8个月以下SIDS婴儿脑内白质的发育与对照婴儿相同，年龄较大的SIDS婴儿白质发育可能比对照婴儿稍超前。MRI上SIDS白质未见缺氧改变。
