Billingsley Rebecca L, Schrimsher Gregory W, Jackson Edward F, Slopis John M, Moore Bartlett D
Division of Pediatrics (Box 87), University of Texas, M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
Arch Neurol. 2002 Apr;59(4):616-22. doi: 10.1001/archneur.59.4.616.
Neurofibromatosis type 1 (NF-1) is associated with learning disabilities and cognitive impairment in childhood and adolescence. Individuals with NF-1 have a propensity for brain hyperintensities on T2-weighted magnetic resonance images, macrocephaly, and optic gliomas. Few clear relationships between these central nervous system abnormalities and cognitive function, however, have been found in this population.
To determine whether planum temporale (PT) and planum parietale (PP) morphologic features are associated with learning disabilities in NF-1.
We measured and compared the surface area, gray matter volume, and asymmetry of the PT and PP on T1-weighted MRIs from 24 children and adolescents with NF-1 and an equal number of controls. Relationships between these measurements and cognitive and academic achievement scores were examined.
The left PT in boys with NF-1 was significantly smaller in both surface area and gray matter volume compared with girls with NF-1 and controls. Boys with NF-1 also showed greater symmetry between the left and right hemispheres in this region compared with girls with NF-1 and controls, who showed a pattern of left greater than right asymmetry of the PT. Intelligence-based discrepancy scores of reading and math achievement, which are commonly used to define learning disabilities, were significantly related to PT asymmetry in the NF-1 group as a whole. Less leftward asymmetry of the PT was associated with poorer reading and math achievement in relation to intellectual test scores.
The high susceptibility of individuals with NF-1 to develop reading and other learning disabilities seems to be related to the development of the sylvian fissure. These results provide further support for the hypothesized association between sylvian fissure morphologic features and learning disabilities.
1型神经纤维瘤病（NF-1）与儿童及青少年的学习障碍和认知损害相关。NF-1患者在T2加权磁共振成像上易出现脑白质高信号、巨头畸形和视神经胶质瘤。然而，在该人群中，这些中枢神经系统异常与认知功能之间的明确关系鲜有发现。
确定颞平面（PT）和顶叶平面（PP）的形态学特征是否与NF-1患者的学习障碍相关。
我们测量并比较了24名患有NF-1的儿童和青少年以及数量相等的对照组在T1加权磁共振成像上PT和PP的表面积、灰质体积和不对称性。研究了这些测量结果与认知和学业成绩得分之间的关系。
与患有NF-1的女孩及对照组相比，患有NF-1的男孩的左侧PT在表面积和灰质体积上均显著更小。与患有NF-1的女孩及对照组相比，患有NF-1的男孩在该区域的左右半球之间也表现出更大的对称性，而患有NF-1的女孩及对照组表现出PT左侧大于右侧的不对称模式。通常用于定义学习障碍的基于智力的阅读和数学成绩差异得分，在整个NF-1组中与PT不对称性显著相关。PT向左不对称性较小与相对于智力测试得分而言较差的阅读和数学成绩相关。
NF-1患者易患阅读及其他学习障碍，这似乎与外侧裂的发育有关。这些结果为外侧裂形态学特征与学习障碍之间的假设关联提供了进一步支持。
