Hydrocephalus Research Paper
Hydrocephalus is commonly referred to as "water on the brain." The so-called "water" is actually cerebrospinal fluid (CSF), a clear liquid that looks like water and is produced in the 4 ventricles (cavities) of the brain, connected by narrow pathways, leading to an increase in intracranial pressure (ICP) [2]. This condition is likely to be fatal if not treated. Fitting of a ventricular shunt diverts the excess fluid from the brain to the thoracic cavity and is a very effective treatment for hydrocephalus. However, these shunts block regularly and their failure is difficult to detect, consuming clinical time and computed tomography or magnetic resonance imaging. A shunt failure would be easy to diagnose if the ICP could be measured routinely
[1]. Hydrocephalus is a lifetime condition, and an ICP monitor needs to be fully implanted and without percutaneous wires to avoid risk of infection. A conventional way of powering an implantable device is to use batteries. However, the ICP needs to be measured at a sampling rate of ∼100 Hz, and these data need to be transmitted outside the brain for analysis, requiring an estimated 10 mW, which renders a battery unable to provide lifetime operation, and to be of a size sufficiently small to implant. Replacing a flat battery requires surgery and introduces new infection risks. A superior solution supporting lifetime implantation would be based on wireless power transfer technologies. An inductive power transfer (IPT) system, as shown in Fig. 1, can be used to enable the power transfer across the skin without direct electrical contacts, although power losses and resultant heating effect need to be managed properly to avoid tissue damage [3]. Heat dissipation around implanted components while delivering large amount of power (15 W) has been reported in sheep studies [4] and a temperature rise can be less than 2 °C.
[1]. Hydrocephalus is a lifetime condition, and an ICP monitor needs to be fully implanted and without percutaneous wires to avoid risk of infection. A conventional way of powering an implantable device is to use batteries. However, the ICP needs to be measured at a sampling rate of ∼100 Hz, and these data need to be transmitted outside the brain for analysis, requiring an estimated 10 mW, which renders a battery unable to provide lifetime operation, and to be of a size sufficiently small to implant. Replacing a flat battery requires surgery and introduces new infection risks. A superior solution supporting lifetime implantation would be based on wireless power transfer technologies. An inductive power transfer (IPT) system, as shown in Fig. 1, can be used to enable the power transfer across the skin without direct electrical contacts, although power losses and resultant heating effect need to be managed properly to avoid tissue damage [3]. Heat dissipation around implanted components while delivering large amount of power (15 W) has been reported in sheep studies [4] and a temperature rise can be less than 2 °C.