Evaluating a novel, portable, self-administered device ("Flicker-App") that measures critical flicker frequency as a test for minimal hepatic encephalopathy in cirrhosis

项目摘要/摘要 肝硬变可引起一系列神经认知障碍，称为肝性脑病。 (他)1.他的范围从轻度脑溢血(MHE)一直到显性脑溢血(OHE)和昏迷，这可能是生命- 具有威胁性。在MHE升级为MHE之前，在其最早阶段识别和治疗HE非常重要 更严重的形式。如果及早发现，MHE可以相对容易地用药物(例如乳果糖， 利福昔明)，以避免进展为OHE和其他并发症。 实践指南建议经常对所有肝硬变患者进行MHE1筛查。然而，许多研究表明， 表明肝硬变患者没有得到MHE8，9的充分筛查。这可能是因为 目前对MHE的心理测量和神经生理学筛查测试复杂且耗时。 它们需要专门的设备和专门培训的人员来管理。 临界闪烁频率(CFF)是闪烁光源看起来融合到 观察者。MHE将CFF从45-50赫兹降低到&lt；39赫兹，14-18赫兹。CFF是最好的神经生理学测试之一 啊哈。CFF最近被证明可以准确地检测MHE并预测总体生存7。然而， 目前，确定CFF需要专门的设备，如Flicker Fusion系统，这不是 在常规临床实践中可用，由于成本较高，不能在家中自行给药， 体积大，操作繁琐。我们开发了一种用于CFF测试的新型设备--Flicker-App 设计成小巧、便携、便宜，而且可以在家中自行管理。该装置包括：(A)一 以25-55赫兹的不同频率产生闪烁光的光源，由 通过蓝牙与(B)安装在iPhone上的移动应用程序(Apple IOS)进行通信，该应用程序管理 确定CFF的协议。我们的目标是在75年内进行试点和可行性研究，以测试Flicker-App 肝硬变患者，为了： Sa 1.确定肝硬变患者(n=75)是否可以在由医生监督的诊所自行使用Flicker-App 研究助理并计算由Flicker-App确定的CFF之间的一致程度 由“黄金标准”的FFS设备确定的CFF，以及EncephalApp Stroop测试的测试分数。 Sa 2.确定肝硬变患者(n=75)是否可以在家中自我管理Flicker-App，包括每天 测量超过1周，每周测量超过6周，并计算对此的依从性 协议和这些CFF测量的可变性。 SA3.对Flicker-App进行任何必要的软件或硬件调整，以促进和简化其 患者基于结构化访谈的自我管理--对研究参与者和 与临床胃肠病专家/肝病专家合作。

PROJECT SUMMARY/ABSTRACT Cirrhosis of the liver can cause a spectrum of neurocognitive impairments known as hepatic encephalopathy (HE)1. HE ranges from minimal HE (MHE) all the way to overt HE (OHE) and coma, which can be life- threatening. It is very important to recognize and treat HE at its earliest stage of MHE before it escalates to more severe forms. If recognized early, MHE can be treated relatively easily with medications (e.g., lactulose, rifaximin) to avoid progression to OHE and other complications. Practice guidelines recommend frequent screening of all cirrhotic patients for MHE1. However, many studies demonstrate that cirrhotic patients are not getting adequately screened for MHE8, 9. This is likely because the current psychometric and neurophysiologic screening tests for MHE are complicated and time-consuming. They require specialized equipment and specially-trained personnel to administer. Critical flicker frequency (CFF) is the minimum frequency at which a flickering light source appears fused to an observer. MHE reduces CFF from 45-50Hz to <39 Hz7, 14-18. CFF is one of the best neurophysiologic tests for MHE. CFF has recently been shown to accurately detect MHE and to predict overall survival7. However, ascertainment of CFF currently requires specialized equipment, such as the Flicker Fusion System, which is not available in routine clinical practice, and is not designed to be self-administered at home due to its high cost, large size, and cumbersome operation. We developed a novel device for CFF testing called “Flicker-App” designed to be small, portable, inexpensive and self-administered at home. The device consists of: (A) a light source that generates a flickering light at different frequencies from 25-55Hz, as controlled by communication via bluetooth with (B) a mobile app (Apple iOS) installed on an iPhone, which administers the protocol for determining CFF. Our goal is to perform a pilot and feasibility study to test the Flicker-App in 75 patients with cirrhosis, in order to: SA 1. Determine whether cirrhotic patients (n=75) can self-administer the Flicker-App in clinic supervised by a research assistant and calculate the level of agreement between the CFF determined by the Flicker-App, the CFF determined by the “gold-standard” FFS device, and the test scores on the EncephalApp Stroop test. SA 2. Determine whether cirrhotic patients (n=75) can self-administer the Flicker-App at home, including daily measurements over 1 week and weekly measurements over 6 weeks, and calculate the adherence to this protocol and the variability of these CFF measurements. SA3. Make any necessary software or hardware adjustments to the Flicker-App to facilitate and simplify its self-administration by patients based on structured interview-questionnaires with the study participants and with clinical Gastroenterologists/Hepatologists.