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1 A MEDICAL DATA MONITORING SYSTEM AND A METHOD THEREOF FIELD OF INVENTION 5 The present invention relates to a medical data monitoring system and a method thereof. BACKGROUND OF INVENTION Advancement of medical science contributes towards the human life expectancy. Naturally, 10 proportions of older persons in the society are increasing. Certainly, taking proper care of these persons is one of the responsibilities of our society. Cardiac rehabilitation is one of the necessary treatments, because of life long non-stop cardiac activities. Electrocardiograms (ECG) is the only way to check heart conditions, and if ECG can be done frequently without leaving home then it is easy to identify the problem by the physician from the ECG history of 15 a person. This has long been requested by physicians. The known technology vary from a simple ECG recorder that can only monitor the ECG signal to a sophisticated system with computer analysis and database. Some ECG recorder has incorporated memory to the device to provide storage for the ECG data and send the 20 digital data to computer for storage later. This type of ECG recorder completes with LCD display, keypad and mechanism to send the recorded ECG data to the computer to make it an independent ECG recording device. Therefore, there is a need for a solution that is able to create health awareness right from 25 home wherein vital medical statistics can be consistently monitored instantaneously. 2 SUMMARY OF INVENTION Accordingly, there is provided a medical data monitoring system, characterized in that, the 5 system is connectible over a network such that data is accessible via the network, the system includes a medical data recorder connectible to a computing means by a microcontroller wherein the medical data recorder further is connectible to a plurality of skin electrodes, a data converter wherein data from the medical data recorder is convertible into a transmittable data format in real time, wherein the medical data recorder further includes 10 an amplifier, a filter and an analog to digital converter. There is further provided a method of monitoring data over a connectible network, characterized in that, the data is accessible via the network, the method includes the steps of detecting signals containing medical data, compressing the medical data and sharing the 15 compressed data through the network in real time. The present invention consists of several novel features and a combination of parts hereinafter fully described and illustrated in the accompanying description and drawings, it being understood that various changes in the details may be made without departing from 20 the scope of the invention or sacrificing any of the advantages of the present invention. 3 BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus 5 are not limitative of the present invention, wherein: Figure 1 shows a block diagram of an ECG recorder in the preferred embodiment of the invention; Figure 2 shows a block diagram of communication protocol in the preferred embodiment of the invention; 10 Figure 3 shows a flow chart showing a method of monitoring data in the preferred embodiment of the invention; Figure 4 shows a dimensional view of the plurality of surface electrodes used in the preferred embodiment of the invention; Figure 5 show circuit diagrams of amplifiers, filters, analog to digital converters, power 15 supply unit and microcontroller in the preferred embodiment of the invention; Figure 6 shows a flowchart of the microcontroller firmware in the preferred embodiment of the invention; Figure 7 shows a circuit diagram of a RS-232 transceiver in the preferred embodiment of the invention; and 20 Figure 8 shows a graphical view of actual detection of heartbeat in the preferred embodiment of the invention. 4 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention relates to a medical data monitoring system and a method thereof. 5 Hereinafter, this specification will describe the present invention according to the preferred embodiment of the present invention. However, it is to be understood that limiting the description to the preferred embodiment of the invention is merely to facilitate discussion of the present invention and it is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the scope of the appended claims. 10 The following detailed description of the preferred embodiment will now be described in accordance with the attached drawings, either individually or in combination. Figures 1 shows a part of the preferred embodiment of a medical data monitoring system 15 (100), connectible over a network such that data is accessible via the network. The system (100) includes a medical data recorder (103) connectible to a computing means by a microcontroller (105) wherein the medical data recorder (103) further is connectible to a plurality of skin electrodes (107), a data converter (109) wherein data from the medical data recorder (103) is convertible into a transmittable data format in real time, wherein the 20 medical data recorder (103) further includes an amplifier, a filter and an analog to digital converter. The medical data recorder (103) used in this preferred embodiment of the invention is an electrocardiogram (ECG) recorder. A computing means is understood to be selected from, but not restricted to, computers, laptops, tablets, palmtop devices, mobile devices and netbooks. 25 The ECG recorder hardware that is used as a computer peripheral connected to the computer via RS-232 port and software written to display the ECG data. The ECG recorder 5 can record single-lead ECG signal with properly placed three skin electrodes in this embodiment. The ECG recorder hardware performs amplification, proper filtering and analog-to-digital conversion to the ECG signal. The microcontroller (105) used in this embodiment is an 8-bit microcontroller is used to control the hardware and to communicate 5 with the computer. The hardware is battery-powered and its design emphasises on low power consumption. The ECG recorder is designed to be also used with hand-held computers such as a palm top device with RS-232 port. The device is safe to use because it is optically isolated from the 240V power line; thus, working independently in a robust and reliable mode. The ECG signal was over sampled at 500 samples per second to improve its 10 fidelity. The software was written in Visual C++ programming language. The software communicates with the ECG recorder to control recording process, monitor battery status and display the ECG signal in real-time while recording is in process with the indication of bad or good ECG 15 data. The software provides a graphical user interface (GUI), which help general user to work with this system. Besides that, the system (100) detects presence of the heartbeat, calculates current heartbeat rate and beat-to-beat interval while recording the ECG data in memory. To make a reasonable file size for easy transmission over the Internet, a simple form of Huffman’s lossless compression is performed to the ECG data before it is saved into 20 a file. The software includes the facility to send the recorded ECG file via e-mail as an attachment together with the patient’s details, record date/time and duration. The system is a low cost portable ECG device, international ECG standard compliance, ease of use, output is comprehensibly readable by patients, portability, low power 25 consumption, storage of data, has data transmission facilities. The system further has a sampling rate of 500 Hz and 12 bits sampling which is the medical standard, has a simple GUI user interface with 3-leads ECG information with various types of viewing facilities and related information (patient’s information, heartbeat, RR interval, zooming), battery operated 6 portable ECG device with international safety medical standards that comply with IEC601-1, AAMI EC11 (protective class). The system (100) has a loss less ECG Data Compression for convenient storage that 5 facilitates continuous ECG information collection for critical applications and/or stress test. The system can be used as an Internet appliance device. The system (100) is not a medical device, wherein the system (100) is a medical support device (like thermometer to check fever at home). This system (100) will check the heart 10 condition prior to get advice from the professional doctor. The ECG recorder includes a plurality of modules such as but not restricted to, amplifier, filter, electrode guarding circuit, analog to digital Converter, power supply unit, Microcontroller (105), opto-isolator and RS-232 Transceiver. Peak value of the ECG signal at the 15 plurality of skin electrodes (107) is in the order of 1mV. The electrode-skin interface forms a galvanic half-cell. The difference between the half-cell voltages of the electrode-skin interface produces a voltage that usually varies slowly during a recording, resulting in a low frequency noise. A cut-off frequency of 0.15 Hz for high-pass filtering is implemented to eliminate the noise. To ensure correct operation with typical electrode-skin impedance and 20 typical interference sources, an amplifier was designed with very high common mode input impedance (>100M at 50Hz), high differential mode input impedance (>10M at 50Hz), high common mode rejection ratio (>80dB) and shielded input cables driven by a proper guarding circuit. 25 The block diagram of the ECG recorder is shown in Figure 1. Three electrodes were used in the ECG recorder in this embodiment, wherein two electrodes are used to sense the ECG signal and the other one is for noise reduction. The weak ECG signal acquired from electrodes is first amplified by the preamplifier with a gain of about 500 before it is filtered by 7 a 96Hz lowpass filter to eliminate most of the electromagnetic noise. The offset null circuit is to eliminate the DC voltage between the two electrodes. The filtered signal is further amplified to about 1V and the offset of the signal is shifted to 1.25V by another stage of amplifier. It is necessary to shift the signal offset to 1.25V so that all the negative voltage is 5 shifted to positive because the ADC accepts pseudo-differential inputs ranging from 0V to reference voltage of 2.50V. The amplified signal is digitized by a 12-bit ADC sampled at 500 samples per second before it is sent to the microcontroller (105) via 3-wire serial interface. In Figure 1, there is shown a power supply unit that produces +5V and –5V needed by the 10 analog circuits. The power supply for analog circuit can be shut off by a control line connected to the microcontroller (105). Besides that, the ECG recorder detects the battery level and signals the microcontroller (105) in case of battery low. The ECG recorder has an 8-bit microcontroller to control its operations like initializing the ECG recording circle, stop recording, shutdown the circuits when there is no activity and monitor the battery status. It 15 also implements the communication protocol between recorder and the computer. The ECG recorder is physically isolated from the computer using opto-isolator for the safety of the patient. This hardware design is in compliance with the international safety medical standards IEC601-1, AAMI EC11 (protective class). The RS-232 transceiver is used to convert the RS-232 signal level from the computer port to Transistor-Transistor-Logic (TTL) 20 level and vice versa. The system (100) of the ECG recorder hardware is powered by three 1.5V battery except the RS-232 transceiver, which is powered by the RTS line of the computer port. The communication protocols between PC and the ECG recorder is illustrated in Figure 2. 25 Figure 3 shows a preferred embodiment of a method of monitoring data over a connectible network, wherein the data is accessible via the network. The method includes the steps of detecting signals containing medical data, compressing the medical data and compressed data through the network in real time. sharing the 8 Data flow diagram in Figure 3 shows the flow of information between different objects and variables for the ECG recorder software. The object can be hardware, Graphic User Interface (GUI), file on disk, variable in the program memory or running thread. The information can be in the form of command or variable passed from one object to another. 5 The ECG software can communicate with the recorder hardware and get data from the recorder. The recorded ECG signal can be displayed at five different scales, via 5mm/mV, 10mm/mV, 20mm/mV, 40mm/mV, and 80mm/mV. The P, Q, R, S and T waves of the ECG signal can be clearly displayed at the scale of 10mm/mV, 20mm/mV, 40mm/mV, and 80mm/m. The recorded ECG signal has noise level of about 0.12mV and can be noticed 10 when displayed at the scale of 40mm/mv and 80mm/mV. The method further controls the recorder hardware and gets the digitized ECG data from the hardware via serial port. The method provides the display of the real time ECG signal, patient’s heartbeat rate and the battery status when recording ECG. When viewing the 15 recorded ECG signal, the user can scroll through the signal by a scroll bar. Besides that, the ECG signal can be zoomed to five different sizes. The method includes compressing the ECG data before saving the data to a file and expands the data when the file is loaded. This makes the ECG file small and easy to send through the Internet. 20 To support system (100) and the method and to realize its potential use, a web based telemedicine data center can be vacillated. Where the user can open an account and upload their ECG information regularly to the medical center for the doctor to analyze. This will provide total freedom to the medical report handling and references. This web based medical data center has various facilities, it also can be expand according to the hospital’s 25 requirements. The system (100) can be used with home care standard equipment, such as glucose meter, BP device, weighing machine, and digital camera for patient’s medical data preparation and storage in the telemedicine data center. 9 The system (100) and method allows for viewing the recorded ECG data in a convenient way, wherein the system (100) has the real-time ECG signal viewing facilities with most important function that indicating a proper ECG signal captured through displaying a vivid blinking (red heart) symbol in the screen. This is very essential for the household and 5 general purpose applications, to know the ECG electrodes are placed correctly and the ECG acquisition are accurate. In other ECG recorder development, the recorder has digital signal processing (DSP) microprocessor to process the ECG signal. With the use of DSP microprocessor, the ECG signal can be digitally filtered and it also allows real-time heart rate determination. This type of recorder can send the ECG signal and heart rate to the computer 10 by radio link in real-time. Because this type of device needs to continuously transmit the ECG signal and heart rate to the computer, the power requirements are high, leading to short battery life. The system (100) is a portable low power consumption device that works with the regular computer as 15 well as laptop and tablet PCs. The system will utilize the processing power and the display facilities of a computer. The Surface Electrodes Surface electrodes are a class of sensor that acquires the naturally occurring bioelectric 20 signal such as ECG. They are placed in contact with the skin of the subject and it is called Skin Electrode as seen in Figure 4. The electrodes for surface recording of biopotential are generally made of silver-silver chloride (Ag-AgCl). With the system’s reusable metal-plate electrode, and reusable suction cup electrode can be used to save the repeated cost of ECG electrode. The normal one time used Ag-AgCl metal contact button at the top of a hollow 25 column that is filled with a conductive gel also can use. It is suitable to be used for long time recording because it can hold well on the skin for long time. 10 Accurate ECG signal accruing In most bioelectric measurements an interference level of 1 to 10μV peak-to-peak (pp) or less than 1% of the pp value of an ECG, is acceptable. 5 Interferences of the ECG signal was handled in two ways which are common mode rejection ratio and high common mode voltage into a differential input voltage, called “the potential divider effect”. Consequently, a very high isolation mode rejection ratio is essential in an isolated bioelectric recording. A high isolation mode rejection ratio can be achieved with modern photo-optically isolation techniques (analog or digital) combined with a high gain 10 front-end. This feature has been used to omit isolation amplifiers with the medical instrument’s safety standards (international safety medical standards that comply with IEC601-1, AAMI EC11 (protective class). An instrumental amplifier (IA) is suitable to be used as the preamplification of small ECG 15 differential signal as seen in Figure 5. The peak value of the ECG signal at the skin surface electrodes is on the order of 1mV. To ensure correct operation with typical electrode skin impedance and typical interference sources, an amplifier should meet the following demands: · Very high common mode input impedance (>100M at 50Hz), 20 · High differential mode input impedance (>10M at 50Hz), · High common-mode rejection ratio (>80dB) · Shielded input cables driven by a proper guarding circuit Data Compression 25 In the case of ECG file, it is important to preserve the actual recorded ECG data when transmitting to the physician for later analysis. Thus, the lossless compression technique is more suitable to be used for the compression of ECG data. For Huffman coding, the actual output of the encoder is determined by a set of probabilities. 11 When using this type of coding, a symbol that has a very high probability of occurrence generates a code with very few bits by means of an algorithm in building a Huffman decoding tree. The tree is then built with the following steps as seen in Figure 6: · The two free nodes with the lowest weights are located. 5 · A parent node for these two nodes is created. It is assigned a weight equal to the sum of the two child nodes. · One of the child nodes is designated as the path taken from the parent node when decoding a 0-bit. The other is arbitrarily set to the 1-bit. · The previous steps are repeated until only one free node is left. This free node is 10 designated the root of the tree. Heartbeat Detection Techniques Accurate detection of R-peak of QRS complex is a prerequisite for reliable function of ECGanalysers. Recognition of almost all ECG parameters is based on a fixed point identifiable at 15 each cycle. R-peak is suitable for use as the datum point, because it has the largest amplitude and sharpest waveform that can be extracted from ECG. The time and amplitude measurements can be performed when the apex of the R-peak is detected at each cycle. There are a numbers of ECG recognition algorithms used in ECG-analysers. Some are based on different types of amplitude triggering, while the others examine the signal in the 20 frequency domain. The adaptive properties of algorithms to the changing signal may differ and some algorithms use statistical methods for identification. For the detection of R-peak, the amplitude level triggering method is based on the square of the derivative. The high frequency components of an original signal are indicated by 25 differentiating the filtered ECG signal. The reliability of the identification is increased by squaring this differentiated value, which will highlight the high frequency components. After this processing, the R-peak can be detected by determining the known amplitude level as a triggering level. The triggering level can also be adaptively determined. Thus, the value of 12 the triggering level is dependent on the upper values of the ECG signal. The differentiation can be carried out by using the two, three and five point methods. The widely used algorithm is the three-point method where the differential at instant n is calculated by dividing the difference between n+1 and n-1 by the time interval (or time differential of the two samples) 5 between these two samples. The method can be further developed by increasing the included time period and number of samples. The error and noise sensitivity of the differentiation decreases when the number of included samples increases, but simultaneously the accuracy is decreasing. 10 The R-wave triggering threshold value can be determined by trial and error to find out the most suitable value. The value of the triggering threshold can adaptively change with the base line value of the ECG signal as seen in Figure 8. The R-peak can be recognized by determining the squared value that is greater than the R-wave triggering value. The current RR-interval can be calculated by differentiating the previous R-wave time with the current 15 Rwave time and the heartbeat can be calculated by the following formula. With health education’s dissemination through Internet, heath awareness has been 20 developed. This is the perfect time to introduce the system (100) at home for general purpose uses. As ECG is a baseline test to check heart condition, and if ECG can be done frequently without leaving home, then it is easy for a physician to identify a problem using ECG history of a person. 25 There are interferences from different sources that disturb the ECG signal recording like the 13 main power supply, magnetically induced interference and the movement artefact. With interference reduction techniques like proper grounding, driven right leg circuit, circuit isolation, shielding of measurement cables, guarding circuit and proper signal filtering, the interferences can be reduced to an acceptable level. Using in home will be no problem with 5 little precaution as normally done in hospital. Any future design changes will be only to change the device’s firmware which is written in assembly language. To transmit the ECG data through the Internet, the data compress algorithm has been used to make the file size smaller for faster transmission. The lossless 10 compression should be used in the medical data exchange, thus Huffman coding was used. The user’s ECG and the users information has been pasted in the same page with the program, thus there are no chances of miss handling the data with users. The system (100) can be used for cardiac research, cardiac rehabilitation, cardiac activities 15 follow-up (like Arrhythmia and Pacemaker), sports, emergency unit (wireless ECG transfer through wireless Internet) as well as regular cardiac care for improving health. The system can expand according to the organizational need. A hospital database can be developed where the individual patient will upload their ECG information regularly from home for diagnostic purposes. 20 This invention is adapted for use for use at home and for transmitting ECG data over Internet. The disclosed invention is suitable, but not restricted to, for use as an Internet medical appliance and as a portable ECG device. 25