Abstract

Background

Mechanical obstruction is the most common cause of shunt failure for hydrocephalic patients. However, the diagnosis is extremely challenging and often requires invasive testing methods. Thus, a simple and non-invasive technique is in urgent need to predict the intracranial pressure (ICP) of hydrocephalic patients during their post-surgical follow-up, which could help neurosurgeons to determine the conditions of the shunt system.

Materials and methods

Two groups of patients were enrolled in the current study. In group I, patients were enrolled as they were diagnosed with high ICP hydrocephalus and received shunt surgery. The shunt valve pressures were taken for their post-surgical ICP. Meanwhile, the participants of group II exhibited abnormally increased lumbar puncture opening pressure (LPOP; from 180 to 400 mmH₂O). Both the ICP and LPOP were used to match with their corresponding tympanic membrane temperature (TMT).

Results

When patients’ ICP were in the normal range (group I, from 50 to 180 mmH₂O), the TMT correlated with ICP in a linear regression model (R² = 0.59, p < 0.001). Interestingly, when patients exhibited above-normal ICP (LPOP was from 180 to 400 mmH₂O), their TMT fit well with the ICP in a third-order polynomial regression (R² = 0.88). When the ICP was 287.98 mmH₂O, the TMT approached the vertex, which was 38.54 °C. Based on this TMT-ICP algorithm, we invented a non-invasive ICP monitor system. Interestingly, a tight linear correlation was detected between the ICP data drawn from the non-invasive device and Codman ICP monitoring system (R² = 0.93, p < 0.01).

Conclusions

We believe the TMT-ICP algorithm (the Y-Jiang model) could be used for preliminary prediction of shunt malfunction as well as monitoring ICP changes.

中文翻译：

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发明无创颅内压（ICP）监测系统——一项脑积水研究的启示

摘要

背景

机械性阻塞是脑积水患者分流失败的最常见原因。然而，诊断极具挑战性，通常需要侵入性测试方法。因此，迫切需要一种简单且无创的技术来预测脑积水患者术后随访期间的颅内压（ICP），这可以帮助神经外科医生确定分流系统的状况。

材料和方法

两组患者参加了当前的研究。在第一组中，患者因被诊断患有高 ICP 脑积水并接受了分流手术而被纳入。分流阀压力用于他们的术后 ICP。同时，第二组的参与者表现出异常升高的腰椎穿刺开放压力（LPOP；从 180 到 400 mmH ₂ O）。ICP 和 LPOP 均用于匹配其相应的鼓膜温度 (TMT)。

结果

当患者的 ICP 在正常范围内时（组 I，从 50 到 180 mmH ₂ O），TMT 与 ICP 在线性回归模型中相关（R ²  =  0.59，p  <  0.001）。有趣的是，当患者表现出高于正常的 ICP（LPOP 为 180 至 400 mmH ₂ O）时，他们的 TMT 在三阶多项式回归中与 ICP 非常吻合 ( R ²  =  0.88)。当 ICP 为 287.98 mmH ₂O, TMT 接近顶点, 为 38.54 °C。基于这种TMT-ICP算法，我们发明了一种非侵入式ICP监测系统。有趣的是，从无创设备和 Codman ICP 监测系统中提取的 ICP 数据之间检测到紧密的线性相关性 ( R ²  =  0.93，p  <  0.01)。

结论

我们相信 TMT-ICP 算法（Y-Jiang 模型）可用于分流器故障的初步预测以及监测 ICP 变化。