DISTRIBUTED MULTIAGENT APPROACH FOR
HYDROCEPHALUS TREATMENT AND MANAGEMENT USING
ELECTRONIC SHUNTING
N. Al-Zu’bi, A. Al-kharabsheh, L. Momani and W. Al-Nuaimy
Department of Electrical Engineering and Electronics, University of Liverpool, Brownlow Hill, Liverpool, U.K.
Keywords:
Hydrocephalus, Electronic shunt, Multi-agent.
Abstract:
Hydrocephalus is a common chronic condition that results in excessive accumulation of cerebrospinal fluid
(CSF) inside the skull, often leading to brain damage. The treatment and management of hydrocephalus remain
a challenging issue, especially for diagnosis, improving current shunt treatment, and predicting shunt success.
Current diagnosis procedure depends mainly on the surgeons’ observation of the clinical symptoms, neuroim-
ages and instantaneous of intracranial pressure recording. These lack accuracy in diagnosis and predicting
the outcome. Dominant treatment relies on passive mechanical shunts; these also exhibit virous problems.
Adding to that, the lack of communication between the community surgeons and a limited understanding of
the hydrodynamics of this disease have limited the effectiveness of hydrocephalus treatment.
This paper proposes a new approach to improve the treatment and management of hydrocephalus through a
multiagent cognitive system over a distributed network of hydrocephalus patients with intelligent shunting
system. This approach will not only develop autonomous treatment method for hydrocephalus, but also it
defines a method for information acquiring and analysis to better understanding hydrocephalus and assess
shunt functionality.
1 INTRODUCTION
Hydrocephalus is an excessive accumulation of cere-
brospinal fluid (CSF) inside the skull due to im-
balance of the production and absorbtion of the
CSF, and without treatment has a 50-60% death
rate (A.D.A.M., 2002). Even though there is no ac-
ceptable statistical information of hydrocephalus pa-
tients, estimates show that approximately 1 in every
500 children are affected by hydrocephalus and this
rate is increasing rapidly (NINDS, 2008).
Despite more than 40 years of shunt development,
hydrocephalus remains a challenging issue particu-
lary in the three critical aspects of diagnosis, treat-
ment and management. This paper seeks to allow the
unification of these aspects by facilitating communi-
cation at all levels.
Nowadays, hydrocephalus is characterised and di-
agnosed by clinical symptoms, like dementia, uri-
nary incontinence, and gait disturbance, and anal-
ysis of neuroimaging either by computed tomog-
raphy (CT) or magnetic resonance imaging (MRI)
coupled with mean value of intracranial pressure
(ICP) (W. Pfisterer, 2007). However, these meth-
ods failed to achieve accuracy in diagnosing hydro-
cephalus and selecting patients that would benefit
form shunting (A. Marmarou, 2005a). In addition to
that, there is no acceptable standard for diagnosis and
treatment of hydrocephalus (A. Marmarou, 2005b).
Currently, the dominant treatment for hydro-
cephalus is to divertthe CSF from the ventricles in the
brain to another part of the body by means of an im-
planted shunt. The currently used shunts are differen-
tial pressure shunts that depend on mechanical valves
for operation. Even with the latests advances in shunt
technology allowing non-invasive adjustment of the
pressure setting, the resulting treatment is far from el-
egant, lacking responsiveness and autonomy, and un-
able to communicate. Several studies have verified
serious problems and shortcomings relating to cur-
rent shunting techniques, such as mechanical prob-
lems and shunt blockage, excessive and insufficient
CSF draining (over-drainageand under-draining),and
others. Shunt failure rate currently stands at 35-
40% (Metzemaekers, 1998). These problems have
been exacerbated by the lack of a viable and meaning-
503
Al-Zu’bi N., Al-kharabsheh A., Momani L. and Al-Nuaimy W. (2009).
DISTRIBUTED MULTIAGENT APPROACH FOR HYDROCEPHALUS TREATMENT AND MANAGEMENT USING ELECTRONIC SHUNTING.
In Proceedings of the International Conference on Health Informatics, pages 503-507
DOI: 10.5220/0001779205030507
Copyright
c
SciTePress
ful communicationchannel between practicing neuro-
surgeons, and the lack of a detailed understanding of
the hydrodynamics of the disease.
The increaseing number of patients suffering from
this disease, and the associated costs of their treat-
ment, have together highlighted the deficiencies of
the current modes of treatment, and has stimulated re-
search towards the next generation of hydrocephalus
shunts. What is beginning to emerge is a totally new
approach towards the treatment and management of
the disease. This approach responds to the needs of
individual patients in an autonomous way, and forms
a network among those patients to establish a man-
agement and learning protocols to better understand
aspects of hydrocephalus diagnosis and treatment.
In order to achieve this goal, the old fashioned”
mechanical shunt valve must first be upgraded to
an electromechanical valve, controlled by software.
This type of shunt will have sensory inputs to al-
low it to process and analyse the patient ICP directly,
and base the patients’ treatement regime on the val-
ues of selected parameters derived therefrom. It has
been demonstrated that certain parameters extracted
from the ICP signal are more meaningful than the
mean or instantaneous ICP in terms of providing in-
formation for diagnosis and predicting clinical out-
come (M. Czosnyka, 2007). Such a system would
be responsive to patient feedback, provind the shunt
with a means of evaluate its own performance, cou-
pled with other derived numeric performance indica-
tors. This can be achieved through communication
between the implanted shunt and a hand-held device,
which could be a normal mobile phone.
This framework of communication, with the abil-
ity of the hand-held device connecting to the inter-
net, gives the ability to connect these shunts in a dis-
tributed network of agents, which could enable shunts
to share their information and disseminate successful
treatment regimes. Moreover, this approach will pro-
vide a platform for classification of ICP signals, hy-
drocephalus patients, and treatment regimes.
2 APPROACH SPECIFICATION
2.1 Intelligent eShunt System
This approach proposes a software-driven,
electronically-controlled shunt replacing the passive
mechanical one. This shunt consists of an electronic
valve, ICP sensor, microcontroller with software, and
a transceiver which provides the shunt two-way to
communicate with the outside word. This modifi-
cation of shunt characteristic by adding autonomy
and intelligence allow us to overcome some of the
problems in the mechanical shunts, farther enables
the system to detect malfunctioning.
2.2 ICP Signal Analysis and Parameters
Depending on symptoms, MRI and mean ICP, for di-
agnosis of Hydrocephalus achieves low accuracy, add
to that cost of treatments and shunt revisions which
exceed $1 Billion in year 2000 (Vacca, 2007). Fur-
thermore, these factors do not reliably predict re-
sponse to treatment or clinical outcome after shunt-
ing (W. Pfisterer, 2007), which leads to emphasis on
discovering new trends and parameters in ICP wave-
form, which carry valuable information about patient
state (M. Czosnyka, 2007).
This approach, by extracting a set of representa-
tive parameters from the ICP signal, enables the elec-
tronic shunt to respond to the dynamics of the ICP sig-
nal and provide a way of controlling the valve on de-
mand. These parameters, such as Pulse amplitude of
the ICP (AMP), RAP index, mean ICP, and mean ICP
wave amplitude and latency, (M. Czosnyka, 2007),
proves efficiency in treatment.
2.3 Distributed Multi-agent
Intelligent agents are an innovativetechnology for de-
veloping complex and distributed systems. These in-
telligent agents have, in an autonomous way, a flex-
ibility in performing actions to achieve their goals.
This flexibility includes reactivity, pro-activity , and
social ability (Weiss, 1999).
Multiagent systems are widely used in healthcare,
medicine and other domains (Moreno, 2003), where
here several novel aspect need to be highlighted:
1. Clustering technique, for clustering patients into
groups.
2. Local and general classification technique for ICP
pattern classification.
3. Performance evaluation technique, for evaluat-
ing agent’s performance, and assigning successful
credit for each case.
4. Using communication language and identification
ontology for agents to announce about their self
and their experiences.
5. Knowledge sharing and negotiation techniques.
This technology provides a suitable choice in this
case, where distributed electronic shunts need to com-
municate and exchange their successful experiences.
These shunts represent a distributed sources of infor-
mation and decision around multiple patients, where
HEALTHINF 2009 - International Conference on Health Informatics
504
single patient (i.e. electronic shunt) does not have
a complete view of the hydrocephalus environment
and does not encounter adequate cases of ICP pat-
terns to develop a general classification and manage-
ment protocol. By sharing data and treatment expe-
rience among electronic shunts in different patients,
more effective treatment and management system can
be developed.
Distributed agents will benefit from the semantic
web technology which will be used for exchanging
information, and interacting and reasoning about their
knowledge (Hendler, 2001), with a defined ontology
domain which define a set of terms and messaging
vocabulary to be used by agents in the communication
language.
While agents are using their knowledge about
their cases and their performance in treatment and
information from other agents, they will be able to
reason about and recommend appropriate treatment
scheme for particular case.
3 APPROACH ARCHITECTURE
3.1 Functionality Overview
The functionality of the approach, goes through the
following steps:
ICP sensing, the eShunt agent senses the ICP sig-
nal through the pressure sensor and store it in the
database of the eShunt.
Preprocessing, the ICP signal is preprocessed to
extract its parameters, like pulse amplitude of the
ICP (AMP), RAP index, mean ICP, true ICP, and
mean ICP wave amplitude and mean ICP wave la-
tency.
Formatting form, the extracted parameters, the
real ICP and other data related to the patient such
as disease history, patient feedback, surgeon ad-
vice and diagnosis, are putted down in a common
form.
Processing, then based on the information in the
form, the eShunt agent tries to discovernew trends
like new thresholds and values of the ICP pa-
rameters with corresponding clinical cases, such
as shunt malfunctioning, patient clinical outcome,
ICP production rate state.
ICP classification, then the eShunt agent, based
on different ICP parameters and processed data,
classify the ICP signal into categories.
Testing, these classifiers are tested using appropri-
ate cases from the distributed eShunt agents.
Patient clustering, including ICP classification,
patient history and patient general information,
patients are clustered into different categories.
The eShunt agent attempts to diagnose its patient
for whom ICP data and other information are avail-
able, uses web service to establish a record of the pa-
tient case information into the system’s blackboard,
in anonymous form. The system via different eShunt
agents may suggest classification and diagnosis based
on their data for similar cases, or the enquiring eShunt
may ask via the net whether certain classification and
diagnosis are appropriate. Then the performance of
the suggested classifications and diagnosis becomes a
negotiation process among the system, and when they
agreed on a satisfied level of performance of the clas-
sifier and diagnosis, the classifier is published.
3.2 Agents Needed
The functionality of the system is fulfilled through the
following agents:
ICP sensing agent to sense the ICP signal and
store it in the database of the eShunt.
Preprocessing agent to extract the specified pa-
rameters from the ICP signal.
Processing agent to discover new trends and
thresholds of the parameters with the correspond-
ing clinical cases.
Classification agent that classifies ICP cases based
on different parameters.
Testing agent that test the locally classified and
diagnosed cases through the distributed system.
Clustering agent that cluster other eShunts in
groups based on similarities.
Communication agent that identify other agents
and establish a communication link with them.
3.3 Layered Framework
Since the system should be both reactive and proac-
tive, reactive to instantaneous ICP changing and do-
ing simple action based on that, and proactive to sup-
port in a timely fashion ICP parameter extraction and
analysis, and negotiation of appropriate case diagno-
sis and corresponding proper treatment, and in addi-
tion that this system is wrapping the eShunt system
which locally control the valve, the system adopts
multi-layer framework. It is composed of the follow-
ing layers:
Inner control layer, represents the eShunt behavior
locally which is limited to controlling the valve in
an instantaneous manner.
DISTRIBUTED MULTIAGENT APPROACH FOR HYDROCEPHALUS TREATMENT AND MANAGEMENT USING
ELECTRONIC SHUNTING
505
Figure 1: System high-level overview.
Processing layer, where ICP analysis is happened.
Database interface layer, it locally logs ICP data,
treatment regimes and stores patient information
in the database.
Processing layer, which mines the data provid-
ing the main functionality of the approach such
as ICP classification, ICP thresholds findings, and
patients clusterings.
Testing layer, where evaluation process occurred
and cases verified through the system.
Communication layer, which provide environ-
ment for agent communication via the web.
Figure 2: Framework layers.
4 CONCLUSIONS
This paper has presented a new methodology for the
integration of hydrocephalus biomedical data and ap-
plying knowledge discovery techniques. It specifi-
cally addresses the use of the valuable information in
the ICP signal coupled with patient feedback and sur-
geon examination and enforced by the eShunt agent,
to improve understanding and management of hydro-
cephalus.
A requirement of a considerable amount of ICP
analysis and treatment data is necessary to build a
self-learning and robust classification system for ICP
waveforms and hydrocephalus patients. This ap-
proach will tackle challenges in analysing, collecting
and managing ICP data, by providing a distributed
system of eShunt agents that manage patients au-
tonomously, and share information between them. It
is envisaged that such an approach will typify the next
generation of hydrocephalus management and treat-
ment; it will undoubtedly reduce treatment costs dra-
matically, and can potentially save lives.
HEALTHINF 2009 - International Conference on Health Informatics
506
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