EXPERIMENTAL DATABASE MEDICAL SYSTEM

Data Acquisition Background and Features

Petr Maule, Jiri Polivka

Department of Computer Science and Eng., University of West Bohemia, Univerzitni 8, Plzen, Czech Republic

Jana Kleckova

Department of Computer Science and Eng., University of West Bohemia, Univerzitni 8, Plzen, Czech Republic

Keywords: Medical Software, Medical Standards, DASTA, DICOM, HL7.

Abstract: This article describes features and background of the upcoming scientific medical system. The ambitious

goal of the system is to provide relevant medical data for various medical methods and experimental

implementations testing. The article presents needs for such system and administrative background which it

requires. The main standards which are used in medical applications are also mentioned, like the DICOM,

DASTA or HL7 format with the relations to our experimental medical system.

1 OVERVIEW

Medical science is quickly evolving branch

providing new treatment techniques and new

diagnosis determination possibilities. Progress of

software computation methods and evolution of new

software algorithms plays the major role. All kinds

of new techniques need to be tested and verified at

large amount of suitable data. These data differs in

context of methods to be verified. Some methods

can strictly require one kind of input data – like one

type of examination as computed tomography (CT)

or x-ray images, etc. Other methods require analysis

of several examination types together. Some

methods can even require sequences of the same

kind of examinations acquired in different time or

they can even have more sophisticated needs for

input data.

The goal of our ongoing medical system is to

offer enough relevant data for all kind of input data

requirements. If there is any new method which

needs to be tested on larger amount of data, the

system can provide it. It will store anonymous data

coming from all our partners – mostly hospitals. The

system will be sophisticated in processing of

heterogeneous multimedia medical data objects.

Also a knowledge-based system using the database

will be proposed. Following parts describe existing

examination types and storing formats, the way how

the data will be transferred from our partners into the

system and description of benefits for all system

users.

2 MEDICAL DATA TYPES AND

STANDARDS

Hospital information systems at the time of their

first introduction had incompatible data formats. The

same problem was with medical instruments – no

mutually compatible formats. Recently the situation

is much better because many standards have been

established. The leading standard in digital imaging

is DICOM standard which provides the same format

for many imaging modalities. DICOM standard is

supported in vast majority of hospital information

systems and medical instruments worldwide. But

there are still data which are non-imaging and need

to be stored as well. Example of such data can be

laboratory examinations or medical diagnosis text

records, etc. For these kinds of data there are mostly

used standards like HL7 and especially in the Czech

Republic DASTA standard. Our system is going to

support DICOM standard and DASTA standard with

future plan for HL7 standard implementation.

402

Maule P., Polivka J. and Kleckova J. (2010).

EXPERIMENTAL DATABASE MEDICAL SYSTEM - Data Acquisition Background and Features.

In Proceedings of the Third International Conference on Health Informatics, pages 402-405

DOI: 10.5220/0002698004020405

 SciTePress

2.1 DICOM Standard

The Digital Imaging and Communications in

Medicine (DICOM) standard begins in 1983 when

The American College of Radiology (ACR) and

National Electrical Manufacturers Association

(NEMA) formed a committee to develop standard

unifying digital information interoperability. Current

version of this standard is DICOM 3.0.

The standard covers many parts connected with

medical imaging information interoperability. It

defines context of information objects for different

modalities as well as possible services operating

with these data objects and it also defines

conformance statement which must be claimed by

DICOM compatible instruments. It also defines

communication interface and media storing

specifications.

2.2 DASTA Standard

The data standard DASTA (DS), established by the

Ministry of Health of the Czech Republic, is used

for transferring important data among various

medical information systems in the university

hospitals as well as in smaller medical facilities. The

current version of the format is DS4 (DS 04.02.04)

and the development is still in progress. The DS

format simplifies communication between many

medical information systems used in the Czech

Republic, which was very complicated before (one

of the medical information systems had more than

30 different protocols and diagnoses code-lists).

The first simple version of DS standard (DS 1.0)

was published in the bulletin of the Ministry of

Health of the CR in 1994. DS 1.0 set up the

conceptual principia of the system, but it was still

weak in data blocks and it didn´t solve the

problematic of the laboratory segment. The next

development tended to set up and improve complex

communication interface with the medical laboratory

information systems and to creation of the national

laboratory items code-list (NLIC). The development

of the first practically usable version of DS (DS1.1.)

and NLIC was completed in 1997. The early version

of DS standard came out from basic text files in

TXT, the next versions used the XML data format

(DS 2 and 3 used DTD, DS 4 are fully exploiting

XML). Important versions, their launch dates and

data formats are:

• DS 01.10 1. 7. 1997 "TXT"

• DS 01.20 1. 1. 2001 "TXT"

• DS 02.01 1. 5. 2002 "DTD"

• DS 03.01 2. 6. 2003 "DTD"

• DS 04.01 1. 1. 2007 "XML"

The next important moment for expansion and

quality enhancement of DS standard was the

supportive web-services introduction. These services

offer full and actual DS4, available documentation,

detailed manual and implemental programs. The

regular four times a year updates are realized by the

web-services too.

At the present time, DASTA standard contains

not only blocks for patient data transfer, but also

blocks for investigation of the drinking and supply

water, diagnoses and laboratory code-lists and

others. In the patient data scope, the current DS

standard allows transfer of the important information

from many areas. For example the patient

identification data, urgent information (allergy,

diagnosis), health insurance company information,

anamnesis, patient medicaments, persistent and

acute diagnosis, vaccinations or special data blocks.

As the example of clinical events, the DS standard

could be used for the laboratory work-up, RDG

examination (RTG, CT and other), pulmonary

function tests, consultation, ambulant and dismissory

report and other.

The main advantage of the DS standard in the

Czech Republic is its domestic background. On its

development participated many medical software

developers, so the DS meet their particular

requirements. Some medical software which use the

DS standard are DATAPLAN, HICOMP, ICZ,

LOGIS, MEDICALC, MEDICON, PCS, SOPHIS,

DS SOFT, DYNATECH and others. DS standard is

used also in Slovakia, although it is not the formal

standard there. The next step could be distribution of

the DS to other counties in the EU.

2.3 HL7 Standard

The HL7 is another international standard in the

clinical and administrative medical data domain. It

was developed by Health Level Seven Inc.

organization, which is accredited by ANSI

(American National Standards Institute) as a SDO

(Standards Developing Organization). This Health

Level Seven Inc. was founded in 1987 as a not-for-

profit volunteer organization like other ANSI-

accredited SDOs. The standard are developed in co-

operation with many various participants, who may

include providers, consultants, vendors, payers and

government groups who are interested in clinical and

administrative standards for health care in the USA

and word wide.

As the other standards, HL7 was developed like

messaging protocol that enable to share and

exchange sets of clinical and administrative data

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among unrelated health care applications and

facilities. The members of HL7 are known as the

Working Group and are organized into special

interest groups (SIGs) and technical committees.

They are looking at end-user needs and hand it on to

the attention of the HL7 Working Group. The HL7

standard is a text-based encoding system.

The first version of the HL7 standard (V.2.x) was

developed and approved as an ANSI standard more

than 12 years ago. The current version (V.3.0) uses

an object-oriented development methodology and a

Reference Information Model (RIM) to create

messages. The definition of the HL7 messages was

relatively free in version V.2.x whereas version

V.3.0 reduces optionality of the message content

which means fewer errors in the messages

interpretation. In the current versions the XML

protocol is used to envelope HL7 message content

which increase system efficiency.

Because of its text-based format, the HL7 is still

human-readable, although it is usually interpreted by

machines and medical software. Several web sites

provide testing HL7 messages and can be used to

test a system´s ability to process the HL7 standard.

3 THE SYSTEM FILLING

As it was already said the system will be fed by our

partners which will be mostly hospitals. Now at the

beginning of the system implementation we have

only one partner – The University Hospital in Pilsen.

For all the partners we need to implement special

export module to respect their information system.

The University Hospital in Pilsen uses WinMedicalc

(WM) information system. WM is used at many

hospitals in Czech Republic. The export module can

be used at all the hospitals which use WM and

decide to become our partner with no need for

modifications. Generally we can say that all

information system mostly covers DICOM, DASTA

and HL7 standards. The export module just exports

data of these standards into our system with

preservation of mutual relation but in anonymous

form.

There are two requirements of our system on

filling process. The first is that data must be able to

be exported on demand and the second that all

targeted data are exported automatically. There must

be also duplicity removal in export module. Export

module also ensures transferring from partner´s

environment into our system environment which

covers some kind of on-line transfers. DICOM and

DASTA standard data are processed separately. The

filling schema of the system is shown in the figure 1.

Figure 1: Filling system schema.

3.1 DASTA Exporting

The DASTA format for export is common XML

format. WM provides export services which

repeatedly look for new DASTA standard data in

hospital information system and all found records it

exports using web services or directly stores it into

preselected directory at selected computer in

common XML file form. At this computer our

export module is running. Export module just waits

for new DASTA records, process them and transfers

it into our system. WM exporting ensures no

duplicity of DASTA information.

3.2 DICOM Exporting

The Export module for DICOM data is more

general. It can be used everywhere where DICOM

standard is used. It is not depended on used hospital

information system. Export module contains

DICOM Application Entity (AET) which is able to

communicate via DICOM standard communication

interface. This module repeatedly asks DICOM

image server for new records, download it, process

and transfers it into our system.

Here is one feature that needs to be solved.

DICOM searching for new data does not ensure

unique data. DICOM communication provides query

system just for data which were acquired at selected

date but the data could be exported also on demand.

There must be stored information in export module

about already exported DICOM data to refuse all

duplicities.

3.3 Patient Identification

The system preserves examinations relations. It

means that we know which examination belongs to

which patient in anonymizated form. During

anonymization process in export module, there is

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assigned unique signature for each patient. This

mapping will be stored only in export module and

stays inside our partner's system (in hospital).

Assigned signature is randomly generated signature

unique in our system. For all further data of this

patient, there will be found mapping in the export

module. It will use the same signature which means

relations preservation.

3.4 Data Size

We are going to transfer large volume of data.

Different examination means different data sizes.

Probably the highest data sizes will come from

DICOM file where one examination can even have

about 4 GB. These data are to be transferred on-line,

so there is required high-speed connection of all

partners.

3.5 Drawbacks

If the patient undergo two examinations in different

hospital information system scope (often means two

different hospitals), it will be presented as two

different patients – now we do not have enough

information for mapping these like occurrences.

4 CONCLUSIONS

Our system is tending to contain large amount of

different medical data provided in DICOM and

DASTA standards and in the future also HL7

standard. All data will be anonymous but mutual

relations will be preserved. This article shortly

describes some of the examination types and storing

formats which we will take into account in our

scientific database medical system, like the DASTA

and HL7 standard, new DICOM standard is also

noticed. We introduced the approach how the data

could be transferred from medical facilities and

other filling partners into our system and mentioned

the benefits for all system users. We will use these

findings in our future research work.

REFERENCES

The DICOM Standard, http://dicom.nema.org

Vcelak P, Polivka J, Maule P, Kratochvil P and Kleckova

J (2009). Experimental database system for the

vascular brain diseases research. Frontiers in

Neuroinformatics. Conference Abstract: 2nd INCF

Congress of Neuroinformatics. doi:

10.3389/conf.neuro.11.2009.08.002

Data Standard MZČR,

http://ciselniky.dasta.mzcr.czHealth Level 7,

http://www.hl7.org

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