An Intelligent Implantable Wireless Shunting System for Hydrocephalus Patients

Abstract

Hydrocephalus is a neurological disorder whereby the cerebrospinal fluid surrounding the brain is improperly drained, causing severe pain and swelling of the head. Existing treatments rely on passive implantable shunts with differential pressure valves; these have many limitations, and lifethreatening complications often arise. In addition, the inability of such devices to autonomously and spontaneously adapt to the needs of the patients results in frequent hospital visits and shunt revisions. This paper proposes replacing the passive valve with a mechatronic valve and an intelligent microcontroller that wirelessly communicates with a handheld device that would have a GUI and an RF interface to communicate with the patient and the implantable shunt respectively. This would deliver a personalised treatment that would aim to eventually reduce or eliminate the shunt dependence. This system would also enable a physician to monitor and modify the treatment parameters wirelessly, thus reducing, if not eliminating, the need for shunt revision operations. To manage the shunt, four methods were investigated, simulated and compared. As a result a method was selected based on performance. This method involves an implantable pressure sensor and intelligent software, which will cooperate in monitoring and determining vital parameters that will help in determining a decision regarding the optimal valve schedule. The decision will be either modifying the schedule or contacting the external device for consultation. Initial results are presented, demonstrating different valve regulation scenarios and the wireless interaction between the external and implanted subsystems. Also presented are important parameters from the ICP data that would help in optimising system resources. To conclude, an intelligent shunting system is seen as the future in hydrocephalus treatment, potentially reducing significantly hospitalisation periods and shunt revisions. Furthermore, a new technique was investigated that would help to circumvent the problem of updating software using readonly memories.