Diffusion tensor MR imaging in the assessment of cognitive functions in children with periventricular leukomalacia

Abstract

Objective To investigate the values of diffusion tensor MR imaging(DTI)and fiber tractography(FT)in the assessment of cognitive functions in children with periventricular leukomalacia (PVL),to facilitate to understand the mechanism of PVL children's cognitive functions.Methods Forty six children with PVL and 16 age-matched volunters were recruited.Developmental quotient(DQ)of all cases was recorded.According to the DQ scores,patients were divided into 3 groups:mild in 11 patients,moderate in 19,and severe in 16.DTI was performed in all cases and fractional anisotropy(FA)values were be calculated.Non-paired t test was used to compare the FA values of major white matter fibers between patients group and controls group.One-way ANOVA was used to compare the FA values among 4 groups.Results Compared with controls,all 46 patients with PVL showed a significant mean FA reduction in left corticospinal tract(CST)(0.476 ±0.064 vs.0.531 ±0.064),bilateral anterior limb of internal capsula (ICAL)(left 0.357 ±0.050 vs.0.405 ±0.081,right 0.370 ±0.040 vs.0.405 ±0.036),posterior limb of internal capsule(ICPL)(left 0.483 ±0.044 vs.0.546 ±0.091,right 0.485 ±0.046 vs.0.547 ±0.083),arcuate fasciculus(AF)(left 0.367 ± 0.069 vs.0.433 ± 0.097,right 0.363 ± 0.064 vs.0.421 ±0.091),posterior thalamic radiation(PTR)(left 0.390 ± 0.059 vs.0.459 ± 0.067,right 0.382 ± 0.047 vs.0.446 ± 0.064),anterior CG(ACG)(left 0.362 ± 0.056 vs.0.423 ± 0.057,right 0.345 ± 0.056 vs.0.417 ± 0.080),superior longitudinal fasciculus(SLF)(left 0.323 ± 0.050 vs.0.426 ±0.102,right 0.341 ± 0.056 vs.0.416 ± 0.092)and splenium of the corpus callosum(SCC)(0.535 ±0.090 vs.0.606 ±0.060)(t =2.037-3.745,P ＜0.05).The severity of cognitive impairment companied with decrease of the FA values of all fibers.The FA values of bilateral CST,ICAL,ICPL,left AF,bilateral PTR,ACG,SLF and SCC were significantly different among different groups(F =3.021-7.146,P ＜ 0.05).Conclusions The damage widespread of white matter bundles is found in children with PVL DTI and FT can provide details in the assessment of cognitive impairment in children with PVL. Key words: Cerebral palsy; Diffusion magnetic resonance imaging; Cognition disorders