Diffusion Tensor Imaging in Patients with Idiopathic Normal Pressure Hydrocephalus

Czech version

Authors: T. Radovnický ¹; D. Adámek ²; M. Derner ²; M. Sameš ¹
Authors‘ workplace: Neurochirurgická klinika UJEP a Krajská zdravotní a. s., Masarykova nemocnice v Ústí nad Labem, o. z. ¹; Radiodiagnostické oddělení, Masarykova nemocnice v Ústí nad Labem, o. z. ²
Published in: Cesk Slov Neurol N 2017; 80/113(3): 328-331
Category: Original Paper
doi: https://doi.org/doi: 10.14735/amcsnn2017328

Podpořeno grantem IGA MZ NT14448-3/ 2013. Děkujeme RNDr. Karlu Hrachovi, Ph.D., z Univerzity J. E. Purkyně v Ústí nad Labem za statistické zpracování dat.

Overview

Introduction:
Idiopathic normal pressure hydrocephalus (iNPH) is a disease with many unanswered questions. General effort is to find a simple and non-invasive diagnostic tool. Magnetic resonance imaging (MRI) is a topic for intensive research. Diffusion tensor imaging (DTI) is one of the MRI modalities. This examination can detect microstructural changes of the cerebral white matter. The aim of this study was to compare the DTI parameters in iNPH patients before and after a surgery and with healthy volunteers.

Material and methods:
MRI was performed in patients before surgery and 1 year after. We also examined age-matched healthy volunteers. The DTI parameters (fractional anisotropy; FA and mean diffusivity; MD) were measured in the anterior and posterior limb of the internal capsule and in the corpus callosum (ALIC, PLIC, CC). Acquired data were statistically analysed. We enrolled 27 patients with iNPH and 24 healthy volunteers.

Results:
MD was higher in all measured regions comparing iNPH and healthy volunteers (p < 0.05). FA was higher in the PLIC only (p < 0.001). Comparing our data before surgery and one year after, we found significant decrease of FA in the PLIC (p < 0.001) but FA in this region did not reached the FA level in the healthy volunteers group (0.63 after the surgery vs. 0.58 in volunteers). No other significant change in FA or MD was noticed.

Conclusion:
This study proved, that the FA in the PLIC is significantly higher in iNPH patients than in healthy volunteers. After the surgery, FA decreased. MD values were significantly higher in iNPH patients in the ALIC, PLIC and CC with no decrease after the surgery. It reflects degeneration of the white matter in iNPH patients.

Key words:
idiopathic normal pressure hydrocephalus – magnetic resonance imaging – diffusion tensor imaging

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers.

Chinese summary - 摘要

特发性正常压力脑积水患者弥散张量成像

介绍：

特发性正常压力脑积水（iNPH）是一种具有许多未解之谜的疾病。我们努力的方向是找到一个简单且非侵入性的诊断工具，而磁共振成像（MRI）正是研究该问题的一个很好的工具。扩散张量成像（DTI）是MRI模式之一。该检查可以检测脑白质的微结构变化。本研究的目的是比较手术前后iNPH患者和健康志愿者的DTI参数。

材料和方法：

手术后1年内进行MRI检查。我们还检查了年龄匹配的健康志愿者。在内囊和胼胝体（ALIC，PLIC，CC）的前后肢中测量DTI参数（各向异性; FA和平均弥散度; MD）。获得的数据进行统计分析。我们招收了27名iNPH患者和24名健康志愿者。

结果：

所有测量区域的MD均高于健康志愿者（p <0.05）。只有PLIC中的FA较高（p <0.001）。比较我们在手术前和数年后的数据，我们发现PLIC中FA的显着降低（p <0.001），但在该区域的FA没有达到健康志愿者组的FA水平（手术后为0.63，而0.58志愿者）。注意到FA或MD没有其他重大变化。

结论：

本研究证实，iNPH患者的PLIC中的FA明显高于健康志愿者。手术后，FA减少。 ALIC，PLIC和CC的iNPH患者的MD值显着高于手术后无降低。这反映了iNPH患者白质变性。

关键词：

特发性正常脑积水 - 磁共振成像 - 扩散张量成像

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