Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio; The Department of Pediatrics, Ohio State University College of Medicine, Columbus, Ohio; Department of Pediatrics, Division of Neonatology, University of Texas Health Science Center, Houston, Texas.
Pediatr Neurol. 2013 Dec;49(6):424-30. doi: 10.1016/j.pediatrneurol.2013.08.026. Epub 2013 Oct 15.
Cognitive and language impairments constitute the majority of disabilities observed in preterm infants. It remains unclear if diffuse excessive high signal intensity on magnetic resonance imaging at term represents delayed white matter maturation or pathology.
We hypothesized that diffusion tensor imaging-based objectively quantified diffuse excessive high signal intensity measures at term will be strong predictors of cognitive and language development at 2 years in a cohort of 41 extremely low birth weight (≤1000 g) infants. Using an automated probabilistic atlas, mean diffusivity maps were used to objectively segment and quantify diffuse excessive high signal intensity volume and mean, axial, and radial diffusivity measures. Standardized neurodevelopment was assessed at 2 years of age using the Bayley Scales of Infant Development, third edition.
Thirty-six of the 41 infants (88%) had complete developmental data at follow-up. Objectively quantified diffuse excessive high signal intensity volume correlated significantly with cognitive and language scores at 2 years (P < 0.001 for both). The sum values of the three diffusivity measures in detected diffuse excessive high signal intensity regions also correlated significantly with the Bayley scores (r(2) 34.7%; P < 0.001 for each). Infants in the highest quartile for diffuse excessive high signal intensity volumes had scores between 19 and 24 points lower than infants in the lowest quartile (P < 0.01). When diagnosed subjectively by neuroradiologists however, Bayley scores were not significantly lower in infants with extensive diffuse excessive high signal intensity.
These findings lend further evidence that diffuse excessive high signal intensity is pathologic and that objectively quantified diffusion-based diffuse excessive high signal intensity volume at term is associated with cognitive and language impairments. Our approach could be used for risk stratification and early intervention for such high-risk extremely preterm infants.
认知和语言障碍构成了早产儿中大多数残疾的主要表现。目前尚不清楚足月时磁共振成像上弥漫性过度高信号是否代表了白质成熟延迟或病变。
我们假设，在一个由 41 名极低出生体重（≤1000g）婴儿组成的队列中，基于弥散张量成像的客观量化弥散性过度高信号强度指标在足月时，将强烈预测 2 岁时的认知和语言发育。使用自动概率图谱，平均弥散率图用于客观分割和量化弥散性过度高信号强度体积和平均值、轴向和径向弥散率指标。在 2 岁时，采用贝利婴幼儿发育量表第三版进行标准化神经发育评估。
41 名婴儿中有 36 名（88%）在随访时有完整的发育数据。客观量化的弥散性过度高信号强度体积与 2 岁时的认知和语言评分显著相关（两者均 P < 0.001）。在检测到的弥散性过度高信号强度区域中三种弥散率测量值的总和也与贝利评分显著相关（r² 34.7%；每一项均 P < 0.001）。弥散性过度高信号强度体积最高四分位数的婴儿比最低四分位数的婴儿得分低 19-24 分（P < 0.01）。然而，当神经放射科医生主观诊断时，广泛弥漫性过度高信号强度的婴儿的贝利评分并没有显著降低。
这些发现进一步证明了弥散性过度高信号是病理性的，并且在足月时基于扩散的客观量化弥散性过度高信号强度体积与认知和语言障碍有关。我们的方法可用于此类高危极低出生体重早产儿的风险分层和早期干预。
