佩梅病的头颅MRI随访改变及与临床分型的关系

MRI changes of Pelizaeus-Merzbacher disease in follow-up and relation with clinical phenotypes

目的探讨佩梅病(PMD)患儿头颅MRI进展特点及其与临床分型的关系。方法分析20例经临床诊断为PMD患儿的MRI随访资料,按首次检查年龄分为小年龄组(<12个月,n=13)和大年龄组(≥12个月,n=7)。临床诊断先天型7例,经典型13例。对不同分组及分型间脑白质髓鞘化程度进行分析和比较。结果首次MRI小年龄组脑叶白质均未髓鞘化,大年龄组额顶叶皮层下、深部及侧脑室周边白质髓鞘化率分别为14.29%(1/7)、14.29%(1/7)、28.57%(2/7)。深部结构除脑桥外,小年龄组髓鞘化均低于大年龄组。随访MR发现小年龄组84.62%(11/13)患儿髓鞘化程度出现改变,大年龄组57.14%(4/7)患儿髓鞘化程度改变。经典型脑叶及深部结构(除胼胝体压部)的髓鞘化进步率明显高于先天型。结论 PMD在MRI上表现为髓鞘化明显迟缓或缺乏,随着病情的进展亦会出现相应变化,影像学改变与临床表型有一定的关系。

Objective To investigate the MRI features and changes in follow-up study of Pelizaeus-Merzbacher disease （PMD） and the relation with clinical phenotypes. Methods Twenty PMD children with clinical diagnosis were included, who were divided into young group （（12 months, n= 13） and old group （≥12 months, n =7） according to the time of first MR scanning. There were 7 connatal form patients and 13 classic form patients. The myelination degree of white mat- ter was reviewed and analyzed on the MRI of different groups and forms. Results On the first MRI, the young group had no myelination but the old group respectively had 14.29% （1/7）, 14. 29% （1/7）, 28.57% （2/7） in subcortieal, deep and periventricular in frontal and parietal lobe. And the myelination rate of deep structures was lower in young group than that in old group except pons. During follow-up, there was 84.62% （11/13） and 57.14% （4/7） children with myelination changing in young group and old group respectively. The progressive myelination rate of lobe and deep white matter （ex- cept corpus callosum） were remarkably higher in classic form than that in connatal form. Conelusion PMD is characterized with a substantial deficit in myelin deposition on MRI, which is found corresponding changes with the progresses of the dis- ease and may be related with clinical phenotypes.