tele neurology

8/2/2019 Tele Neurology

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More expertises and related articles from Dipl. Ing. Armin Grtner: http://www.baaske-medical.comBaaske Datentechnik Grenzstrasse 26 32361 Preussisch Oldendorf Tel. +49 (0) 57 42 921 561 http://www.baaske.net

Teleneurology and requirements of the Medical Devices Directive (MDD)written by Dipl.-Ing. Armin Grtner

Teleneurology represents a procedure for the improvement of medical treatment of neurological

patients at distant locations using information and communication technologies (ICT). At smallerhospitals without any own neurology department, patients suspected apoplectic stroke or others canbe cared for by a teleneurologist of a neurological center who advisorily supports his internalspecialist on the spot. This is guaranteed by a video conference technology adapted for medicalengineering. Since according to definition components applied in teleneurology represent medicaldevices, safety standards according to the Medical Devices Directive and all relevant standardsconsidering the third edition of the IEC 601-1 for teleneurology will be presented in the followingfrom the technical point of view.

1. Purpose of Medical Devices Directive (MDD)

The Medical Devices Directive regulates the development, manufacture, putting into circulation andoperation of medical devices. Based on these regulations, the law pursues the objective to providefor the safety, suitability and performance of medical devices as well as the protection required forpatients, users and third parties.

The scope of regulation of the Medical Devices Directive comprises any kind of medical devices,mechanical as well as electrical, and for this reason does not exclusively deal with x-ray machines,saline drips, but also with software, dental products as well as dentists chairs and many more,because the Medical Devices Directive says: Medical devices are all instruments, apparatuses,

appliances, substances and preparations made from substances or other devices, applied bothindividually or in combination, including the software used for the medical devices proper

application, intended by the manufacturer to be used for the diagnosis, prevention, monitoring,treatment or abatement of diseases, injuries etc....

This means that telemedical devices and systems and the required technical components of thevideo conference technology along with the transmission network are subject to the Medical DevicesDirective as well.For this reason, a manufacturer of a telemedical system such as for example for teleneurology, isrequired to

determine the medical purpose following para. 3 clause 10 Medical Device Directivecarry out the risk classification and risk management (DIN EN 14971) andto completely meet the requirements (MDD, annex I) and

to process the conformity evaluation procedureThese sub-processes represent the prerequisite that the manufacturer of a medical device provesand explains (declaration of conformity) the conformity of a medical device with the appropriatedirective such as MDD 93/42 EWG (Medical Device Directive).

The demands on medical devices in the sense of the MDD are far beyond the demands on medical-technical devices as described in standards (DIN EN 60601-1, DIN EN 60601-1-1, DIN EN 60601-2-Xand others). The harmonized standards published in the official gazette of the EC are considered asthe so-called Rules of Technology and are taken as a reference to prove conformance with thestate of technology and the respectively applying fundamental requirements of annexes of theEuropean guidelines. Standards e.g. deal with constructional demands on mechanical and electrical

safety, on ergonomics, EMC-compatibility and further safety criterions for (medical-)technicaldevices.


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However, medical devices are not just subject to the MDD, but the provisions of the Atomic EnergyAct (Atomgesetz), the Radiation Protection Ordinance (Strahlenschutzverordnung), the X-RayOrdinance (Rntgenverordnung) and the Act on the Prevention of Radiation(Strahlenschutzvorsorgesetz), the Chemicals Act (Chemikaliengesetz), the Dangerous SubstancesOrdinance (Gefahrstoffverordnung) as well as the legal provisions on secrecy and data protection and

others shall apply and be stuck to as well.

2. Teleneurology

Teleneurology is applied for neurological acute expertise, for more difficult neurological examinationstati, particularly in the field of brainstem symptomatology and differential diagnostics.The systemic fibrinolysis on the spot, requiring an internist and a neurologist, contains a furtherapplication area.According to picture 1, teleneurology represents a procedure in which a video conference connectionbetween the examining doctor, the patient and the distant diagnostician is provided for thetransmission of video and audio recordings between the persons involved. The teleneurologist e.g.

asks the patient for certain reactions, observes his pupil motor activity and may assist the examiningdoctor in diagnostics by using a mobile telemedical system (also called mobile examination unit ormobile video trolley) with a special camera and microphone as well as the required flat screens,computers, software and network connection.

Picture 1: Procedure of teleneurology

Picture 2 shows a mobile telemedical system that can be rolled to the patients bed as a mobile tooltrolley for sending video and audio recordings of the patient as well and of the examining doctor to adistant neurological center via a wideband line, where a teleneurologist at a special work stationaccording to picture 3 can communicate with the patient and his collegue on the spot via the usedcommunication technology. The system shown in picture 2 is categorized as a medical device of the

risk class 1 and is placed into circulation as a medical device system.


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Picture 2: Example of a mobile telemedical system (source company Meytec)

A telemedical system as illustrated in pictures 1 - 3 thus represents a system according to para. 10clause 2 MDD. It may be composed ofmedical devices and non-medical devices and moreovercovers a wideband connection between distant locations. This system represents a video conferencetechnology specially adapted for (medical) technology and as a whole put in circulation as a medicaldevice. This means the system inclusive of all its components shall be subject to the operatorsordinance as well, requiring in para. 2 clause 1 ...that medical devices are only allowed to be

exclusively established, operated, applied and maintained according to their purpose, in compliancewith the generally approved regulations of technology as well as industrial safety and accident

prevention regulations. As a consequence, the operator is required to observe and comply with e.g.the standards 60601-1 and 60601-1-1 and VDE 0751 concerning electrical safety.


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Picture 3: Work station of the teleneurologist (source company Meytec)

Picture 3 shows an exemplary work station at which the teleneurologist is sitting in the event of acall, and via the connection he can see the patient and his internal-medical colleague on the spot andspeak to them.

3. Formal legal safety

Telemedicine from the MDDs point of view and the operators ordinance

All kinds of telemedical applications are subject to the requirements of the Medical Devices Directive,should they be used for supporting diagnosis and therapy (teleconsultation, second opinion,

assessment of diagnostic findings etc.). Picture 4 represents a diagram of the functioning of a systembetween different houses.


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Picture 4: Functioning of a teleneurological system

Picture 2 shows a product of the risk class 1 (Medical Devices Directive) as a mobile tool trolley.Commercial solutions are usually categorized as a class I medical device according to the MDD93/42/EWG directive, since they are operated neither immediately at nor in physical contact with thepatient. They represent a technical system for the assistance during diagnostic work as well as theusage of consiliary services of other doctors and clinics involved. Mobile systems are usually rolledinto the immediate environment of the patient (following DIN EN 60601-1-1) and are required toaccordingly comply with the safety requirements resulting thereof.

In teleneurology, from the Medical Devices Directive point of view, a network-based connectionbetween distant hospitals is built up. Within the scope of admissal a manufacturer of commercialsystems is therefore required to carry out the risk assessment for a network connection as well byanalyzing and assessing which risks are likely to arise and how the user/operator could e.g. protectthe patient against a possible damage in the event of a sudden breakdown of the networkconnection.

As an example, the assigned purpose prescribed according to para. 3 clause 10 MDD could be definedas follows:

The system is a mobile telediagnosis system and serves as an aid for the assistance during diagnosticwork as well as the usage of consiliary services of other doctors and clinics involved.

The risk assessment in the event of an interruption of the connection or the network e.g. could be asfollows:

Actions in the event of a systems breakdown or breakdown of parts of the systemA connection fails, a connection is interrupted. A consiliary assistance is impossible, building

up a new connection, if required at another location.Image transmission failed, continuation of consultation only by voice connection.


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Image and voice failed, establishing a new connection.Voice failed, establishing a new connection.Image files not available, sending and/or receiving malfunctioning, new selection andcalling/sending of data set.Total breakdown: The system does no restrict the self-dependent actionalibility of the doctor

on the spot.The doctor being with the patient decides self-dependently on the further progress of theexamination. If necessary, it may be required to establish another alternative communicationline or to transfer the patient to another ward. The analysis of images gained from othermodalities shall be carried out at the location of creation and/or storage. The results shall becommunicated to the treating doctor.

In-house production (new: own production) according to para. 12 MDD

Should an operator himself establish a telemedical connection of conventional components by whichhe supports or even carries out diagnosis and interpretation of findings, he builds up a system in the

form of an in-house production following para. 12 MDD and is required to carry out and prove asimplified conformity assessment procedure for this. It is dealt with in-house production wheneveran operator himself establishes a device or a system used for diagnosis and/or therapy. The in-houseproduction of medical devices is regulated by legislation in the third MDD Amendatory Act accordingto which para. 12 shall exclusively apply to devices or systems established at the place of operationwhere they are exclusively used. However, this means that according to regulations themanufacturer as well as the operator must not put these devices and systems into circulation on theSingle European market and not hand them over to third parties either. A simplified conformityassessment procedure means the operator is not required to issue any declaration of conformity orto intervene any notified body, but to be able to prove compliance with fundamental requirementsinclusive of the clinical assessment, risk management and documentation requirements.

Due to the restriction of in-house production to the place of operation, the operator himself for thisreason cannot establish any telemedical system in the form of in-house production, since he isalways required to build up a connection between the actual place of operation (hospital I) and asecond location (hospital II, outside his location). And this is no longer an in-house production whichmeans the procedure of the simplified conformity assessment cannot be applied in this situation.

An in-house production of a telemedical system in the sense of the MDD is only possible betweendifferent buildings at one and the same location.

(Remark: In the draft of the third MDD Amendatory Act of September 2005 the current regulation ofthe in-house production is further restricted and modified.)

Medical Devices Operator Ordinance (German: MPBetreibV)

In the Medical Devices Operator Ordinance, the establishment, operation, usage and maintenance ofmedical devices according to para. 3 Medical Devices Directive is regulated. This includes e.g. all x-raysystems, their related components for the interpretation of findings and distribution of digital imagessuch as findings workstations, PACS-systems etc.

For the purposes of processing as a medical device, telemedical systems are subject to the operators

ordinance. As a consequence, all requirements of the operators ordinance regarding inventory

listings, starting-up formalities, documentation, instruction and maintenance shall apply for atelemedical system as presented in the pictures 1, 2 and 3 based on the example of teleneurology.


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Picture 5: Patients environment according to DIN EN 60601-1 third edition

The mobile telemedical system consists of different components such as monitor, computer, videocamera, microphone and amplifier, loudspeaker as well as related software (conference software,operating system etc.). As a computer, a so-called medical PC is used in the mobile unit according topicture 6, built according to DIN EN 60601-1, sticking to the admissible leakage current according tostandard, having a potential equalization pin and which is determined and suitable for being used in

the immediate patients environment.

Picture 6: Mobile telemedical system in patients environment


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Compliance with these requirements as described in the system standard DIN EN 60601-1-1 is one ofthe fundamentals for the conformity assessment procedure of the system.

Moreover, picture 6 shows that the connection between the mobile examination unit and thenetwork connection is required to be galvanically isolated, to avoid any interference or equalizing

current that may flow e.g. via metallic conductors or shielding getting on the examination unit via thenetwork connection and as a consequence into the patients environment.

Additional potential equalization

Since the housing of the mobile unit consists of touchable, conductible parts (metal) etc., all partsand devices of the trolley, as far as categorized as protection class 1 and having touchable,conductible housing parts, are required to be provided with an additional potential equalization andto be included in the overall potential equalization. Consequentially, the mobile unit shall have acentral potential equalization pin, by which the operator must connect the mobile unit while in

operation via an additional potential equalization with the potential equalization of the room.

Picture 7: Example of additional potential equalization pin at a mobile video trolley

The additional potential equalization serves for the limitation of possible potential differencesbetween different conductible parts of a system within the patients environment. Thus, it represents


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a safety philosophy that understands to preventively avoid voltage drops and differences betweenconductible formations as a driving force for equalizing current with risk potentials for the patientand the user.

Even if the mobile examination unit presented in picture 2 according to regulations is not connected

with the patient, a touch by the patient and/or the doctor or nursing staff is nevertheless possible.

Galvanic isolation

Since according to regulation the mobile unit is provided for sending and transmitting data, agalvanic isolation according to picture 8 between the transmitter unit and the hospital network isrequired, in order to avoid any stray current flowing from the network on the movable unit via thenetwork cable.

Picture 8: Example for a galvanic isolation between the network connection and the mobileexamination unit (Source: Baaske Datentechnik, www.baaske.net)

Space group according to VDE 0100 Part 10

VDE 0100 Part 710: 2002.11.01 Establishment of low-voltage plants, medically used areas containsdemands on voltage supply at hospitals and other institutions of the public health system. It defines

medically used areas and divides them, according to the scope of application, in the space groups 0,1, and 2. Mobile teleneurological examination units are applied in space group 1 (ambulance rooms)as well as in space group 2 (intensive care etc.).

Radiation Control Law

After evaluation of findings by a radiologist, CT-images taken of stroke patients if necessary areplaced at the teleneurologists disposal via a corresponding line with an appropriate bandwidth, since

usually interpreted images are sent in DICOM-quality. As the teleneurologist does not carry out anyevaluations of findings of radiologic images, but receives images and findings from a radiologist, theconnection between the radiologist carrying out the evaluation of findings and the teleneurologist

does not represent any teleradiology connection subject to authorization in the sense of theRadiation Control Law.


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5. DIN EN 60601-1 (3rd

edition) and telemedicine

The standard existing as a IEC-version since 12/2005 also deals with the connection of medical

devices with networks like an imaging modality with a PACS-system. In July 2007, the standard cameinto force as DIN EN standard.

For an operator, a standard primarily does not have any normative or legal obligation. Standardsrepresent regulations of technology where it is referred to and which are applied. Standards aredeveloped in a partially tedious and elaborate approval process and regulate and standardize onlygeneral, fundamental requirements. Due to these time-consuming prozesses, standards usuallycannot represent the (latest) state of the art.

The obligation to pay attention to, to comply with and to realize the state of the art such as e.g. DINEN 60601-1 and other standards in the field of medical technology, results from the Medical Devices

Directive (MDD 8) and der Medical Devices Operator Ordinance. The following obligation isdescribed in para. 2 clause 1 (generel requirements) of the Medical Devices Operator Ordinance(MPBetreibV) which is based on the MDD:

Para. 2 (1) Medical devices may be built up, operated, applied and maintained exclusively accordingto their assigned purpose and according to the provisions of this ordinance, the generally approvedregulations of technology (standards) as well as the regulations for industrial safety and accidentprevention.

This paragraph involves the nexus between the Medical Devices Directive and standards, i.e. thisapplies for the third edition of the DIN EN 60601-1 with its requirements for telemedicine as well.

The third edition has been reviewed over the past five years (since about 2000): Explicitedescriptions, requirements and regulations regarding telemedicine naturally cannot be found in thisstandard, since on the one hand a standard always regulates general requirements and on the othertelemedicine has not been and is not yet the focus of attention of this standard at the time ofcompletion of the draft standard.

The 3rd edition of the IEC 601-1 came into force as DIN EN standard in July 2007 and has replaced the2nd edition. The current designation (October 2006) is:

DIN EN 601-1 (VDE 0750 Teil 1) Medical electrical devices part 1: General definitions for safetyinclusive of substantial characteristics (approved as IEC 601-1 already in 2005).

The new 3rd edition has an impact on telemedicine as well. Chapter 14.13 of the standard deals withthe connection between a Programmable, Electrical Medical System (PEMS) and other devices bynetwork and data communications network.

A telemedical connection (teleneurology) provides such a connection as described in DIN EN 60601-1in paragraph 14.13.

This section of the standard describes the information a manufacturer/suppler is required to includein this technical descriptions for an operator, if a PEMS is connected with other devices by a networkor data interconnections, that are beyond the PEMS-manufacturers responsibility.


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The following information shall be contained in the technical description:&nb

The manufacturer shall specify the features of the network or data interconnection requiredby the PEMS to achieve its intended use and to comply with the assigned purpose following 3 clause 10 MDD.

The manufacturer shall list all possible risks resulting from the fact that the network or thedata interconnection is no longer in the position to provide the features specified.The standard requires the manufacturer to draw the responsible organizations , i.e. the operators

(hospital, medical practice) attention to the following risks specified in the technical description:

The connection of a PEMS with a network or a data interconnection enclosing other devicesmay lead to previously unknown risks for the patient, operator or third parties.The operator (hospital, medical practice) should determine, analyse, assess and control theserisks. (The suitable instrument for this represents the risk management according to DIN EN14971 as described in chapter 5.3).

The operators attention shall be drawn to the fact that the following amendments of the network or

data interconnection could involve new risks and therfore require new analyses.

Amendments at the network or data interconnection may comprise the following measures:

Connection of additional devices with the network or data interconnectionRemoval of devices from the network or data interconnectionDevices connected with the network or data interconnection shall be brought up to dateImprovements of devices connected with the network or data interconnection.

Which consequences and meanings do these requirements of the 3rd edition finally have ontelemedicine and the operator?

A separation between medical technology (medical device) and IT-technlogy (network or central datastorage on a server) is functionally and technically no longer possible. The standard defines theinformation transmitted as a part of the network or data interconnection as that one determined bythe manufacturer for transmission.

5.1 Responsibility for the system integration

The operator of ME-devices and ME-systems (ME = medical-electrical), such as telemedicalapplications, is required to appoint a so-called system integrator who shall responsibly care for thetasks resulting from the standard. The standard justifies this demand by the fact that ME-devices areapplied as well that primarily have not been developed for cooperating with other ME-devices or ME-sytems. For this reason the standard demands a position as a system integrator, in practice calledsystem administrator as well, who is responsible for seeing to it that all individual ME-devicessatisfactorily cooperate in an integrated system as well.

The system integrator shall perform the following tasks and have the following know-how:

How is the integrated system intended to be used?What are the demands on performance of the integrated system?How is the planned system configuration intended to look like?Which restrictions are likely to occur regarding the expandability of the systemDocuments about the specifications of all ME-devices and other devices to be integratedWhich performance does each ME-device and other devices represent?How does the information flow within and around the system take place?


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Manufacturers usually cannot take on the task of a system integrator at the hospital since they havenot the complete information and data recorded in advance. The standard restricts themanufacturers responsibility to the provision of the required information via his device; it cannot be

divided between different manufacturers either. Of course, an operator such as a hospital or amedical practice may instruct a manufacturer or perhaps even a service provider to integrate their

system. In this case, the overall system becomes a ME-system from which the manufacturers orservice providers responsibility may be derived to establish a correctly integrated system.

The system integrator should have the competence and experience for naming and assessing riskslikely to result from the integration of a system and guarantee that remaining, possible (residual)risks are detected during operation of the system.

For the job definition of a system integrator, this means that he

is required to plan the integration of all ME-devices or ME-systems and non-medical devicesin compliance with the instructions of different manufacturers,

has to carry out the risk management at the integrated systemshall forward all manufacturers information to the operator, i.e. the hospital or the medical

practice requiring it for a safe operation of the integrated system.The standard requires such manufacturers information including pointers and warnings about risksas well that could arise because of configuration changes (upgrades, updates). This takes for grantedthat manufacturers inform the named system integrator about all software updates and upgrades,but hardware modifications as well.

Ideally, the operator should prepare a complete documentation about network-connected systems,so also telemedical systems, and document or update modifications (technical modifications,software modifications, upgrades etc.) accordingly.

For this task, the system integrator is required to be aware of and apply the risk managementstandard DIN EN 14971.

5.2 Considerations for building up a network or data interconnection with risk management in

compliance with DIN EN 14971

The standard explains that from a PEMS-manufacturers point of view any kind of network or datainterconnection represents a source of additional reasons for risks. Conversely, this means that nonetwork or data interconnection beyond the manufacturers control may be considered as reliable.


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Picture 9: Networked connection of modalities in a radiology department

The following possible reasons for risks in a network or data interconnection may arise:

data lossinappropriate data exchangedata corruptioninappropriate temporal data matchingunexpected data receptionunauthorized access to datadestructive data.

Examples for ME-devices and ME-systems in the network and data interconnection:

Networked connection of modalities at PACS and WEB-based electronic image distribution

according to picture 9Server-based database for longtime-ECG-devicesTelemedical applicationsWLAN-connection of patients monitorsand others


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Picture 10: Telemedical connection

Annex A of the DIN EN 14971 contains questions about the identification of characteristics of amedical device that could have an impact on safety. Following DIN EN 60601-1 the application of thisannex with regard to reasons and risks of networks and data interconnection among others should atleast include and consider the following considerations and risk reasons and risk potentials:

Teleservice and telemedicine with external access to the internal network or datainterconnection of an operator (hospital or others)Remote service of modality manufacturersCompatibility of operating systemsModifications and upgrade of the software (operating system, applications etc.)Impacts and consequences of patch managementInterface management (example incompatibility of 10 MB network interface cards with a 100MB Ethernet network or others)Connections (modification of hardware, network plug)

Protocols such as DICOM, HL7 in the network or data interconnectionStructure of packet address and bandwidthHeterogeneous network topologyNormal network load and bandwidth requiredTop network loadSafety and long-term readability of data mediaSafety with regard to destructive software, non-authorized software updates or upgradesMaximum permissible response timePermissible error rate of the network or data interconnectionAvailability in the event of scheduled and non-scheduled maintenanceInconsistency of interfaces and formats likely to involve losses of accuracy during data

transmissionetc.


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Annex D of the DIN EN 14971 describes exemplary risks and other factors in connections between aME-device and network or data interconnection:

Which foreseeable abuse may arise?

Is the connection with the network or data interconnection carried out in compliance with itsuse or purpose in accordance with the regulations of para. 3 clause 10 of the Medical DevicesDirective or does it contravene?May an incorrect data flow to or from any connected or involved PEMS arise?What shall the medical data transmitted via the network or data interconnection achieve andwhat is intended to happen to it? What happens in the event of a breakdown of the networkor data interconnection during data transmission?May variances of stipulated operating features of any PEMS involved occur?Which characteristics and operating features does a PEMS have and how and in which formmay they be influenced by the network or the data interconnection?Does there exist a complete description of the parameters of the network or the data

interconnection such as network topology, configuration, parameters, bandwidth (100 MBEthernet, 1GB Ethernet etc.) etc.?Is it possible that an overload of the network or the data interconnection may occur in thenetwork nodes?Is the network load resistant? Is the planned number of network nodes sufficient? Are thereany redundancies? Is there a structured network cabling?Does there exist the risk of user errors and if there is any, which one? Which vocationaltraining and skills is the operator required to have to appropriately operate and administratethe network?How are the configuration and patch management of the network and connected PEMSmade? May regular service work change the features and characterstics of the network ordata interconnection e.g. in the event of remote service? Which impact do remote service,patch management etc. have on connected PEMS such as modalities and others? Does thesystem administrator care for the approval and admission of patches at operating systemlevel, antivirus protection etc. and does he check the consequences on PEMS and network?Does the medical data arrive completely at the correct place at the correct receiver? Arethere any unforseeable modifications likely to occur which the user diagnoses in time?Are there sufficient documentations for all hard- and software components as well as for thesoftware with all updates available at any time?

IEC 601-1 classifies networks and data interconnection according to picture 11 in compliance withthe criterions A, B and C, to achieve a statement about consequences as well as required responsetimes. With regard to the connection of PEMS with a network or a data interconnection, responsetime means the time delay between the occurrence of an error in the network or datainterconnection and the occurrence of an impairment of the patient. Table 1 contains possible risksaccording to severity and response time in the event of data loss or data modification in a network ordata interconnection.


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Severety Response time Network class Examples

Death or severe injury Second(s) A Infusion (closed loop),operation robot,controlling error

Minute(s) A Unavailable

transmission of alarmsignals of an intensive-medical network

Hour(s) A/B Defective therapy dataat dialysis machine orrespirator

Medium injury Second(s) A Defective transmissionof alarm signals,operation robot, robotcontrolling error

Minute(s) A/B Defective transmission

of alarm signals,operation robot, robotcontrolling error

Hour(s) B Image falsification, lossof a therapy protocol

Minor injury Second(s) B

Minute(s) B Loss of image of an x-ray

Hour(s) B/C Failure of a telemedicalconnection

Insiginificant Second(s) C

Minute(s) CHour(s) C Breakdown of a

telemedical connection

Table 1: Possible risks according to severity and response time in the event of data loss orinterferences in the network or data interconnection


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Picture 11: Classification of a network or data interconnection in the categories A, B and C

Class C-network or data interconnection

Class C contains all time-critical processes and applications whose malfunction or interruption mayinvolve a time-critical situation for a patient, such as regarding an intensive-medical network inintesive care. Such a network should not be connected with the general hospital network since sucha connection may cause uncontrolled dangers. The availability of such an isolated (floating) networkis required to be very high, interruptions should not take place often. Such a network is exclusivelysubject to the manufacturers/suppliers responsibility, who defines the demands on the usednetwork nodes as well.

Remark: In practice, such an isolation of networks at hospital may be achieved only with a high

technical effort or not at all. According to manufacturer, x-rays, laboratory data and other patient-

related information is shown on the patients monitors of intensive-medical systems as well; this

requires a connection between the intensive-medical network and the general hospital network in

order to transfer data such as x-rays from the PACS. In this case, however, the responsiblity for the

operation of such networks is definitely shifted to the operator by legislation.

Class B-network or data interconnection

This category of networks or data interconnections contains all non-time-critical applications orprocesses dealing with therapeutic or diagnostic patient data. Via a defined and controllable orsecured interface, such a network may be connected with another network like e.g. a hospitalnetwork. The demands on availability of such a network are high, so that interruptions should take

just short periods.


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The responsibility for such networks is either assigned to the manufacturer or the systemadministrator appointed by the operator. Since such class-B networks usually are radiologic network,the assignment of responsibility always becomes problematic if modalities of several manufacturersfor such a network are placed at disposal.

Class A-network or data interconnection

The general hospital network may be taken as a class-A example; this is a network or datainterconnection where general applications inclusive of administrative or demographical patient datarun in. The standard considers a longer shortfall of availability as acceptable, since usually thehospital provides for alternatives.

The responsiblity for such a network is placed on the system administrator appointed by theoperator.

In practice, such a closed or clear categorization/classification will hardly be possible. The following

example shall explain why in practice there is always a mixture of the three classifications:

A class-B radiology network sends pictures and findings data of the radiology network to a PACS-server (Picture and Communication System) via the general class-A hospital network. Then theradiologic pictures are available to all users and can be accordingly called up in the respectiveoperating rooms, intensive care units etc. via a WEB-distribution. Some manufacturers of intensive-medical monitoring systems categorized class C proposed by standard offer the possibility to show x-rays on the bedside monitor of the intensive care unit. In the professional hospital routine, there is aclear mixed operation of the three network classes mentioned. It is decisive that the third edition ofthe DIN EN 60601-1 is now dealing with the increasing networking of medical-technical devices withnetworks and server-based databases and with the required system administrator and riskmanagement according to DIN EN 14971 and proposes to cover complexity and potential risks oftelemedical approaches and techniques from the safety-related point of view.

Telemedicine is not yet explicitely described in this third edition of the DIN EN 60601-1, but thechapter about network and data interconnection contains the approaches described to deal with thisdevelopment.

The standard assumes that if using a network or data interconnection with the objective of a dataexchange between PEMS and PEMS or with other IT-devices (e.g. server and databases) themanufacturer and operator have the know-how required for building up, controlling andconsequently know such networks together with all their related processes and functions.

As an example, the standard obliges manufacturers or suppliers of PEMS and/or networks and datainterconnections to choose the configuation of their products to such an extent that they complywith internationally known network standards such as Ethernet, Fast Ethernet, GigaBitEthernet, FDDIand others and to appropriately use the available bandwith according to the use in accordance withthe regulations and the purposes of processing following para. 3 clause 10 MDD and to achieve theoptimal performance for their application.

The third edition of the DIN EN 60601-1 requires that a hospital as an operator, represented by asystem integrator, and PEMS-manufacturers come to an agreement about all important technicalparameters in order to guarantee a reliable installation of PEMS operated in a network or in a datacommunications network. This procedure is called for in order to possibly avoid unacceptable risks.


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Table H.4 of the standard e.g. contains a listing of parameters required for the description of anetwork or for the description, documentation and determination of a data communicationsnetwork. However, this listing just represents a draft that should be considered as the beginning of acomprehensive documentation.

6. Summary

For ensuring a top-quality and safe patient care, the operation of telemedical systems such as amongothers in teleneurology requires observing and keeping to the Medical Devices Directive and safetystandards as described in the regulations of technologies (standards). Particulary the third edition ofthe DIN EN 60601-1 is substantially stronger directed to the operator of telemedical connectionsthan the second edition. For the operation of a safe and top-quality telemedicine such asteleneurology, compliance with the safety standards described is indispensable.

Author:

Herr Dipl. Ing. Armin Grtner.b.u.v. SachverstndigerEdith Stein Weg 8

40699 [email protected]

Literature and list of references

1. Grtner, A.; Telemedicine and computer-based medicine, seriesMedizintechnik und Informationstechnologie TV Media Verlag 2006,ISBN 3-8249-1004-7

2. DIN EN 60601-1; VDE 0750-1:1996-03, 1996-03 Medical ElectricalDevices - part 1: General Safety Regulations (IEC 60601-1:1988 +A1:1991 + A2:1995); German version EN 60601-1:1990 + A1:1993 +A2:1995

3. DIN EN 60601-1-2 VDE 0750 part 1-2 Medical Electrical DevicesPart 1-2: General Safety Regulations Collateral standard:Elektromagnetic compatibility requirements and tests

4. DIN EN 60601-1-4; 2001-04 Medical Electrical Devices - Part 1-4:

General Safety Regulations; Collateral standard: Programmableelectrical medical systems (IEC 60601-1-4:1996 + A1:1999); Germanversion EN 60601-1-4:1996 + A1:1999


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5. DIN EN 60601-1; VDE 0750-1:2004-07 Draft Standard, 2004-07Medical Electrical Devices - Part 1: General Safety Regulationsinclusive of substantial performance features(IEC 62A/449/CDV:2004); German version prEN 60601-1:2004

6. EN 55011 : 03.91 DIN EN 55011: 1997: Limit values and measuring

procedures for the radio interference suppression of industrial,scientific and medical high-frequency devices (ISM-devices)

7. EN 55011/A1 :1999; Modification 1 to EN 55011: Industrial, scientificand medical high-frequency devices (ISM-devices)- radio interferencesuppression limit values and measuring procedures (IEC/CISPR11:1997 modified)

Picture 1:

Transmission teleneurology

Clinic A: the stationary work station with the diagnosing doctorClinic B: mobile examination unit at the patients bed

Mobile unit

Picture 5:

PATIENTS ENVIRONMENTIEC 60601-1, future edition 3

- Reviewed demonstration / requirement- Dimensions : Minimum dimensions in the unrestricted environment

Picture 6 :

Medical area with patients environmentMedical device within patients environment

Galvanic isolation of data line

Picture 9:

Central X-ray department

Befundung: evaluation of medical findingsFarbmonitor: color screenBildstelle: place of imagingCD-Brenner: CD-burnerDurchleuchtung: screeningBildverteilung: image distributionBildbetrachtung: image viewing


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Picture 10:

Example for teleneurology

Patient at hospital, CT-evaluation of medical findings by teleneurology

CT-evaluation of medical findings by teleradiologistImages evaluated in DICOM-formatTeleneurology in neurology center

Picture 11:

Severety Response time Network class Examples

Death or severe injury Second(s) A Infusion (closed loop),operation robot,controlling error

Minute(s) A Unavailable

transmission of alarmsignals of an intensive-medical network

Hour(s) A/B Defective therapy dataat dialysis machine orrespirator

Medium injury Second(s) A Defective transmissionof alarm signals,operation robot, robotcontrolling error

Minute(s) A/B Defective transmission

of alarm signals,operation robot, robotcontrolling error

Hour(s) B Image falsification, lossof a therapy protocol

Minor injury Second(s) B

Minute(s) B Loss of image of an x-ray

Hour(s) B/C Failure of a telemedicalconnection

Insiginificant Second(s) C

Minute(s) CHour(s) C Breakdown of a

telemedical connection

PEMS in a hospital networkPossible draft of a networkClass C network: independent of hospital networkClass B network: controlled connection with hospital networkClass A network: hospital networkRadiologienetzwerk: radiology network

Allgemeines Kliniknetz: general hospital network