Agarwal Ajay, Kapur Gaurav, Altinok Deniz
Department of Radiology, University of Missouri, Columbia, MO, USA
Department of Nephrology, Children's Hospital of Michigan, Detroit, MI, USA.
Neuroradiol J. 2015 Dec;28(6):638-43. doi: 10.1177/1971400915609338. Epub 2015 Oct 29.
Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiologic syndrome characterized clinically by headache, seizures, and altered sensorium and radiological changes which are usually reversible. The purpose of this study was to describe the spectrum of magnetic resonance imaging (MRI) findings in childhood PRES, to determine the common etiologies for childhood PRES, and to have an insight into the pathophysiology of PRES.
The MRI results of 20 clinically diagnosed cases of PRES between July 2011 and June 2013 were reviewed. The final diagnosis of PRES was based on the clinical presentation and the MRI features at the time of presentation, which resolved on the follow-up imaging. The medical records of the patients were reviewed to determine the underlying medical disease.
Eight out of the 20 patients included in the study were on cyclosporine or tacrolimus based immunosuppressant therapy for kidney transplant. Four patients had severe hypertension at presentation. The most common MRI finding was high T2-fluid-attenuated inversion recovery (FLAIR) signal in the cortex and subcortical white matter of both cerebral hemispheres, particularly in the parietal and occipital lobes (n=16). The second most common MRI finding was increased leptomeningeal FLAIR signal (n=7). Out of seven patients with leptomeningeal signal, five demonstrated leptomeningeal enhancement as well. Four out of these seven patients had no other parenchymal findings.
Childhood PRES is commonly seen in the setting of immunosuppressant therapy for kidney transplant, severe hypertension and cancer treatment. There was high incidence of increased leptomeningeal FLAIR signal and leptomeningeal enhancement in our study. It supports the current theory of endothelial injury with increased microvascular permeability as the potential pathophysiology of PRES. Also, absence of elevated blood pressure in majority of the patients in our study supports the theory of direct endothelial injury by some agents leading to vasogenic edema.
后部可逆性脑病综合征（PRES）是一种临床 - 放射学综合征，临床特征为头痛、癫痫发作和意识改变，放射学改变通常是可逆的。本研究的目的是描述儿童PRES的磁共振成像（MRI）表现谱，确定儿童PRES的常见病因，并深入了解PRES的病理生理学。
回顾了2011年7月至2013年6月期间20例临床诊断为PRES的患者的MRI结果。PRES的最终诊断基于临床表现和就诊时的MRI特征，这些特征在随访成像中消失。查阅患者的病历以确定潜在的内科疾病。
纳入研究的20例患者中有8例正在接受基于环孢素或他克莫司的免疫抑制治疗以进行肾移植。4例患者就诊时患有严重高血压。最常见的MRI表现是双侧大脑半球皮质和皮质下白质，特别是顶叶和枕叶的高T2液体衰减反转恢复（FLAIR）信号（n = 16）。第二常见的MRI表现是软脑膜FLAIR信号增强（n = 7）。在7例有软脑膜信号的患者中，5例也表现出软脑膜强化。这7例患者中有4例没有其他实质病变。
儿童PRES常见于肾移植免疫抑制治疗、严重高血压和癌症治疗的背景下。在我们的研究中，软脑膜FLAIR信号增强和软脑膜强化的发生率很高。这支持了目前以内皮损伤伴微血管通透性增加为PRES潜在病理生理学的理论。此外，我们研究中的大多数患者血压未升高，这支持了某些药物直接导致内皮损伤从而引起血管源性水肿的理论。
