=Paper= {{Paper |id=Vol-2805/paper11 |storemode=property |title=Personal Data Protection with Smart Cards in Eye-Ground Pathology Identification Computer Systems |pdfUrl=https://ceur-ws.org/Vol-2805/paper11.pdf |volume=Vol-2805 |authors=Yosip Saldan,Lubov Zagoruiko,Tetiana Martianova,Sergey Sergienko,Dmytro Chernov,Iryna Ivanochko,Alya Zilgaraeva |dblpUrl=https://dblp.org/rec/conf/citrisk/SaldanZMSCIZ20 }} ==Personal Data Protection with Smart Cards in Eye-Ground Pathology Identification Computer Systems== https://ceur-ws.org/Vol-2805/paper11.pdf
    Personal Data Protection with Smart Cards Using Eye-
           Ground Image Recognition Technique

 Yosip R. Saldan1[0000-0002-3925-9197], Lubov V. Zagoruiko2[0000-0002-6958-8696], Tetiana A.
Martianova3[0000-0002-8700-8050], Serhiienko P. Sergey4[0000-0001-6213-6833], Dmytro V. Cher-
nov5[0000-0001-7173-0842], Iryna Ivanochko6[0000-0002-1936-968X], Alya K. Zilgaraeva7[0000-0002-
                                            0405-1863]


                 1Pirogov National Medical University of Vinnytsia, Ukraine,

                                    ysaldan@ukr.net,
                   2Stus National University of Donetsk, Vinnytsia, Ukraine

                             l.zahoruiko@donnu.edu.ua,
       3t.martianova@donnu.edu.ua, 4s.serhiienko@donnu.edu.ua,
                              5d.chernov@donnu.edu.ua,
                            6Universityof Vienna, Vienna, Austria
                         iryna.ivanochko@univie.ac.at
                 7Satbayev University, Almaty, The Republic of Kazakhstan

                                 alya_zk@mail.ru.



       Abstract. This work analyzes the methods and computer tools for recognition of
       diabetes-affected eye-ground images and offers the theoretical grounds for meth-
       ods and computer aids fit for recognition of eye-ground images in case of diabe-
       tes. The methods, algorithms and architecture of software and hardware tools for
       eye-ground pathology identification have been developed and demonstrate the
       capability of the cryptographic methods in smart-card functionability; such meth-
       ods are to ensure confidentiality and integrity of patients’ and doctors’ data within
       an eye-ground pathology identification computer system. The eye-ground image
       recognition is based on automatic tracing of an individual blood vessel. The de-
       scribed in the paper process generates a sequence of parameters which character-
       ize the condition of the vascular system and can be used for pathology assessment
       and authentication process as well. The use of eye-ground image (which is unique
       enough for every individual) for authentication allows to reduce risks of data
       breaches in health sector.

       Keywords: image recognition, eye-ground image, authentication, ocular pa-
       thology identification, multiprocessor solutions, graphics processing units
       (GPUs), smart card, personal data protection.


1      Introduction

Diabetes-induced pathologies are among the major causes, worldwide, of poor sight
and blindness and are nowadays the least identifiable and treatable diseases. The result-
ant severe pathological changes entail persistent loss of visuality functions in patients
over 50 [1,2,3,4]. In recent years, such pathologies tend to become “younger”. Actually,

Copyright © 2020 for this paper by its authors. This volume and its papers are published under
the Creative Commons License Attribution 4.0 International (CC BY 4.0).
early manifestations of diabetes-triggered eye-ground pathological changes are oph-
thalmoscopied even at the age of 12 to 20 years [5]. It is noteworthy that a significant
rise of morbidity rate is observed among the able-bodied categories of the population,
inasmuch as the longevity of older people has increased, thereby increasing their share
in the overall population [6]. In the USA, eye-ground pathologies hold the second place,
after diabetes, among the causes of blindness. In Ukraine, the situation, as to the extent
of diabetes-induced eye-ground pathologies, is worsening all the time [7]. For instance,
for the last 20 years, the annual quantity of the first-revealed sight-disabled patients
suffering from such pathology has increased 2.5 times [6].
    The public health industry makes an intensive use of automated systems which allow
to store data electronically. Such systems enhance the data exchange efficiency between
health institutions, enable a remote access to health data systems, simplify and speed
up patients’ check-in procedure with the use of an electronic reception desk. Therefore,
we can assert that health electronic information serves as a basis for many processes in
the present-day health industry [8,9,10].
    However, the major shortcoming of the modern computer systems lies in the fact
that the access to a patient’s case record for entering, modifying or deleting any infor-
mation there is granted without the knowledge of the patient. As a result, such systems
are not safe, inasmuch as they cannot ensure confidentiality and integrity of infor-
mation. The systems that handle such important data as information about human health
should be well secured [11,12,].
    The main attention should be focused on ensuring safe access to information, pro-
tection of the data being transmitted and usage of electronic signatures. The solution to
such problems consists in using doctor’s and patient’s smart cards for definite identifi-
cation of a doctor and a patient in a unified base of electronic medical cards (records).
The use of such smart cards in computer systems would ensure a safe access to infor-
mation and safe storage of confidential data of a patient. The safety of such information
resources is provided with cryptographic methods [13,14].
    The objective of this work consists in upgrading of diabetes-induced eye-ground pa-
thology recognition method and software tools, usable for pathology identification, and
to demonstrate its possibility of person authentication to ensure confidentiality and in-
tegrity of the corresponding medical data system [15,16] and reduce risks of data
breaches.


2      Development of Diabetes-Induced Eye-Ground Pathology
       Computer Recognition Method

Early diagnosis automated system is an expert system used to forecast the evolution
and to assess the treatment efficacy of diabetes-induced vascular diseases. The image
processing engines (modules) are based on well-known algorithms. The user shell runs
in the MS Windows XP operating system environment. This shell has been developed
with the use of Borland Delphi 5 tools. The system database accommodates a set of
reference samples and the patients’ details. The information about patients includes a
list of patients; a list of patients’ visits to a doctor; eye-ground images taken in the
course of each visit; and per-visit image processing results [14, 17]. While processing
the images, the vascular areas are selected and the processing results are tabulated.
Moreover, while doing so, it is possible to classify such results into several user-defined
groups of vessels. The graphic user interface allows, at a time, to view, on the screen,
such things as the image under analysis (with zoom-in/out feature) (Fig. 1), the patient’s
details and diagnostic parameter values to be assessed, as well as the blood vessel gauge
variation diagram for the given area [14,18,19].




                         Fig. 1. Diagnostic mode graphic interface

The task of pathology recognition consists in the following. Automatic tracing of an
individual blood vessel is carried out from a user-set starting point to an end point in
the direction of the blood vessel as found out in the current point. The width of a blood
vessel is defined as a quantity of non-zero counts on a line which is perpendicular to
the direction of the blood vessel. After the width has determined, the starting point is
shifted by a certain user-set tracing increment in the direction, which is found out from
among the pre-computed directions as the one most close to the direct line towards the
end point. Such tracing process generates a sequence of parameters which characterize
the condition of the vascular system and can be used for pathology assessment [20,21].
   See the diabetes-induced eye-ground pathology biomedical image analysis flow
chart in Fig. 2 below.
      Fig. 2. Diabetes-induced eye-ground pathology biomedical image analysis flow chart



3      Development of Computer System Architecture

The computer system is a combination of two major components: the hardware and the
software. The hardware component includes graphic processing units (GPU) and an
external eye-ground image acquisition device (fundus camera). The software consists
of the image enhancement unit (IEU), image analysis unit (IAU) data unit (DU). See
the computer system architecture, as developed by the authors hereof, in Fig. 3 below.
The computer system is implemented in Borland’s DELPHI environment. In terms of
hardware, the system must incorporate a graphics adapter with a pixel-shading feature.
This computer system (Fig. 3) is intended for ascertaining the location and the area of
a pathology, as well as for clusterization and diagnosing of eye-ground pathologies. It
has been decided to use, for the hardware platform, an nVidia video card based on the
GeForce 250 chipset, which is an affordable and fairly efficient solution.
                           Fig. 3. Computer system architecture



4      Personal Data Protection with Smart Cards in Eye-Ground
       Pathology Identification Computer Systems

A smart card is a plastic card which looks exactly like a medical insurance policy card.
It has a built-in chip which accommodates an autonomous memory space and a cryp-
toprocessor (a microcomputer built in a plastic card). The chip’s memory contains a
unique user certificate and other personified data (e.g. the patient’s profile and health
data). The cryptoprocessor provides the operating logic for the card, including genera-
tion of key pairs and an e-signature.
   To start using a computer system which contains electronic case records, a user has
to connect his/her smart card to the card reader and enter a PIN code. Three consecutive
processes occur thereafter:

1. identification (a procedure of user recognition according to his/her identifier);
2. authentication (a procedure of user’s identity proving);
3. authorization (a procedure of granting the user a certain right of access to the system
   resources).
   There are two types of cards: a patient card and a doctor card. The patient card has
an open memory domain and a closed memory domain. The open memory domain con-
tains the basic data (the patient’s surname and name, date of birth, blood group, name
of insurance company, etc.). Such data should be readily available to any medical
officer for delivery of urgent aid to the patient. However, such information should be
safeguarded against any unauthorized changes.
   The protected memory area contains the data which are required for the patient’s
identification, as well as the public key certificate of the doctor who has signed the card.
The protected area is accessible only for the medical officers who use their smart cards.
Other information about the patient’s health status (the case record) is stored on the
medical institution server and is available only to a relevant health officer.
   The other type of smart cards is a doctor card (or specialist’s card). This card con-
tains the surname and name of the health officer (specialist), the name of the health
institution where he/she is employed, the field of specialization, the personal number
and the e-signature. The doctor smart card gives access to the protected information
stored both on the patient card and on the health institution servers. However, the health
officer (specialist) can get access only to the information, which he/she is entitled to
according to the field of his/her specialization.
   A doctor smart card must contain an identifier and a key pair (the e-signature key
and the e-signature verification key). So, such card must have the protected memory
areas intended for safe storage of the key data. Apart from authentication, such doctor
smart card is used for signing up electronic personal health records.
   An eye-ground pathology identification computer system makes use of both types
of smart cards; it consists of two elements, viz. a PC and a fundus camera and functions
as follows. Upon a successful identification and authentication of the doctor and the
patient with the use of the smart card, the image received from the fundus camera or
from another external eye-ground image acquisition device (EEGIAD) goes over to the
image processor (graphics processing unit - GPU), consisting of several units, such as
image enhancement unit (IEU), image analysis unit (IAU), data unit (DU) and base of
experiments.
   Having received an eye-ground image, the IEU performs the biomedical image qual-
ity improving operations, such as:

1. brightness and contrast editing;
2. image inversion;
3. grayscale discrimination;
4. application of different filters (Sobel, Canny, etc.).

   Having performed the image quality enhancing and pre-processing operations, it is
necessary to analyze the parameters of the image in the IAU. This unit carries out op-
erations on image binarization, image contour detection, image segmentation, delinea-
tion of individual elements in the image and computation of the area thereof.
   Sorting out of the results within the above-said unit is given over to the GPU-level.
Such solution has immensely reduced the size of the output arrays (64 to 256 times
depending on the size of the rank area).
   Having delineated the contours of the image items of interest (entities), we arrive at
a respective eye-ground outline picture (EGOP). After such contour delineating opera-
tion, we have the following parameters of image items:

─ item center coordinates;
─ item color;
─ description.

    Such data will be further used for pathology clustering analysis. After normalization,
it is necessary to perform clustering and diagnosing of eye-ground pathologies. Having
conducted all research required, it is necessary to make a diagnosis for a patient.
    The data unit incorporates:

─ a built-in base of main pathology classes;
─ a base of auxiliary subclasses;
─ a base of known diseases;
─ a base of patients (a doctor smart card is to be used).

  The base of experiments incorporates:

─ a list of patients (patient smart cards are to be used);
─ a list of examinations (date and time of the examination, patient’s reference num-
  ber/code, diagnosis);
─ patient’s eye-ground image;
─ an eye-ground outline picture (EGOP);
─ examination reports.

   The output of the graphics cards is connected to the data display device to visualize
examination reports.
   To start working with the system, one has to undergo a doctor’s or patient’s identi-
fication and authentication procedure with the use of a relevant smart card (Fig. 4).
           Fig. 1. Doctor’s or patient’s identification and authentication procedure

   Upon a successful completion of the identification and authentication procedure, the
program main working area comes up (Fig. 5).




                             Fig. 2. Program main working area

Acquisition of Eye-Ground Image
  There are two possible sources to obtain/retrieve an eye-ground image:

1. from an external device (fundus camera);
2. from a file.

   The image acquisition operation can be initiated from the File menu or by pressing
the Open button.

   Biomedical Image Quality Enhancing Operations
   Upon successful uploading of an eye-ground image, if required, it is possible to per-
form the biomedical image quality enhancing operations such as, such as:

1. brightness and contrast editing (using the slider under the image);
2. image inversion;
3. grayscale discrimination;
4. application of different filters (Sobel, Canny, etc.).

  All these functions are available in the Filtration menu (Fig. 6).
             Fig. 3. Execution of biomedical image quality enhancing operations



4.1    Analysis of Image Parameters

Upon completion of the image quality enhancing and pre-processing operations, the
image parameters are analyzed. The operations of image binarization, image contour
detection, image segmentation, delineation of individual elements in the image and
computation of the area thereof are initiated in the Analysis menu or with the Item
Selection buttons. Using the Selection Accuracy and Selection Density features, it is
possible to vary the quality (level) of processing and analyzing of the elements, as well
as their subsequent classification. As soon as the operation on outlining the items is
completed (Fig. 7), we get an eye-ground outline picture (EGOP) on the left.
                             Fig. 4. Eye-ground outline picture

The next step is to analyze the image items. To do so, press the Outline button (Fig. 8).




                          Fig. 5. Results of image items analysis

For convenience of visual perception, the red square boxes in the eye-ground outline
picture highlight the centroids of the resultant items, while the items are shown in dif-
ferent colors. The Items Manager (Fig. 8) lists the parameters of the resultant items:

─ item center coordinates;
─ item color;
─ description.

  Such data will be further used for pathology clustering analysis.

4.2    Clustering and Diagnosing of Eye-Ground Pathologies

Basing on the results of normalization, one can perform clustering and diagnosing of
eye-ground pathologies. To do so, press the Classification button (Fig. 9).
                         Fig. 6. Item clustering analysis window

The clustering analysis window incorporates the following tabs:

─ the normalized data tab, which contain the data of the items;
─ the clustering analysis tab, where a graph is drawn and where one can select the type
  of link and distance measurement (Fig. 10);
─ - the protocol tab, where the examination report is shown (Fig. 11).




                   `

                             Fig. 7. Clustering analysis window




                             Fig. 8. Examination report window



4.3    Patient’s Diagnosis

Having conducted all research required, we can receive a diagnosis. To do so, use the
Diagnosing button (Fig. 12).
                              Fig. 9. Diagnosing window


  This window accommodates:

─ a built-in base of main pathology classes;
─ a base of auxiliary subclasses;
─ a base of known diseases;
─ a base of patients.


   Examination Log
   Upon authentication with the use of his/her smart card, a doctor can select the re-
quired patient and enter the diagnostic data and/or his/her recommendations. After
pressing the Save button, all examinations are recorded in the Examination Log (Fig.
13).




                               Fig. 10. Examination Log
This window accommodates: a list of patients; a list of examinations (date and time of
an examination, patient’s reference number/code, diagnosis); - patient’s eye-ground im-
age; an eye-ground outline picture (EGOP); a Print Report button.


4.4    Printing of Examination Reports

 It is possible print out an examination report. To do so, press the Print Report button
 in the window (Fig. 12), and the report printing window comes up (Fig. 14).




                             Fig. 11. Report printing window

The computer system is implemented in the Borland DELPHI environment. The sys-
tem’s hardware must include a graphics adapter with pixel shaders.
   The computer system, suggested herein, is intended for locating and computing a
pathology area, as well as for clustering and diagnosing eye-ground pathologies.


5      Results of Experimental Research into Pathology Localization
       and Pathology Area Assessment and Results of Experimental
       Research into in Clusterization of Eye-Ground Pathologies

The database for the experimental research was furnished by Filatov Eye Pathology and
Tissue Therapy Research Institute of the Academy of Medical Science of Ukraine. It
contains over 500 images obtained with the use of a ZEISS VISUCAM LITE fundus
camera (Germany). Upon enhancing the quality and pre-processing of such image, it is
necessary to analyze its parameters. Having delineated the contours of the image items
of interest (entities), we arrive at the respective eye-ground outline pictures (EGOPs).
The next step is to identify all items so outlined for existence of a pathology, if any,
and for the area thereof.
   In Table 1, below, see the results of identification of item-related parameters in the
input test picture, as shown in Fig. 15.
                                     Fig. 12. Input test picture


Table 1. Item-of-Interest-Related Parameter Identification Results in the Above Input Test Pic-
                                             ture

                  X Midpoint Coordi-              Y Midpoint Coordi-
     Item                                                                       Area, mm2
               nate                            nate
     1            46                              25                            28.4
     2            48                              15                            5.5
     3            63                              7                             10.7
     4            66                              22                            19.3
     5            72                              13                            19.6
     6            76                              9                             3.1
     7            87                              23                            26.4
     Total area, mm2                                                            113.0

   In Table 2, below, see the results of localization of pathology and assessment of the
area thereof.

Table 2. Results of Experimental Research in Localization of Pathology and Assessment of the
                                       Area Thereof

                      Pathology      Zone         Total Area,                Pathology Per-
     Picture
                    Area, mm2                     mm2                     centage
     1                2                           3                          4
     1                154.3                       6486.5                     2.38
     2                1398                        5929                       23.58
     3                711.2                       6404                       11.11
     4                1138.5                      6446                       17.66
     5                1381.3                      5632.5                     24.52
     6                1047                        6445.5                     16.24
     7                703.4                       6437                       10.93
     8                1490                        6488                       22.97
     9                133.6                       6471                       2.06
     10               113.0                       6387.5                     1.77
     11             1184.7                      6197.5                          19.12
     12             968.3                       6261.5                          15.46
     13             1224.5                      6397.5                          14.45
     14             864.8                       6452                            13.4
     15             922                         6392.5                          14.42
     16             694                         5814.5                          11.94
     Average pathology percentage, %                                            13.88

   The analysis of the results demonstrates that the bulk-information-based segmenta-
tion method, based on assessment of the quantity of information, as developed by the
authors hereof, exceeds by 5 to 25% in terms of the FOM criterion, and is not much
inferior, in terms of RMS criterion, to Roberts, Prewitt and Sobel operators.
   Upon outlining of the image items of interest (entities), acquisition of EGOP, local-
ization and assessment of the area of pathologies, it is necessary to perform clustering
and diagnosing of such eye-ground pathologies. In practical ophthalmology, the fol-
lowing parameters are deemed to be clinical implications of pathology:

─ location of an item in question (post-equatorial location, equatorial location, location
  within the disk of optic nerve, etc.);
─ color (black, pigment-free, pink etc.);
─ size (diameter, height).
   Proceeding from Table 1, above, let us sum up data in a tabular form for pathology
cluster analysis (Table 3).

                     Table 3. Input data for Pathology Cluster Analysis

     Item of in-
                        Item Location            Color                    Size, mm
  terest
     1                  Equatorial               Yellow                   6,0
     2                  post-equatorial          White                    2,6
     3                  post-equatorial          White                    3,7
     4                  post-equatorial          White                    4,9
     5                  post-equatorial          Yellow                   4,9
     6                  post-equatorial          Yellow                   1,9
     7                  post-equatorial          Black                    5,8

   To reduce the measurement error, let us use normalization. This will yield atypicality
in terms of all equal-weight factors which is required for optimal clusterization of pa-
thologies (Table 4).

                 Table 4. Normalized Data for Pathology Cluster Analysis

     Item of in-
                        Item Location           Color                     Size, mm
  terest
     1                  1                       0.39                      1
      2                   0.6                                   0.01                 0.43
      3                   0.28                                  0.01                 0.62
      4                   0.88                                  0.01                 0.82
      5                   0.52                                  0.01                 0.82
      6                   0.36                                  0.01                 0.32
      7                   0.92                                  0.99                 0.97

   See the results diabetes-induced eye-ground pathology clusterization in Table 5, be-
low.

Table 5. Results of Experimental Research into Eye-Ground Pathology Clusterization with the
                                    Full-Bond Method

      Item 1                     Item 2                                New Cluster          Distance
      2                          6                                     8                    0.0697
      3                          5                                     9                    0.0976
      1                          4                                     10                   0.1912
      9                          8                                     11                   0.2756
      10                         7                                     12                   0.9845
      11                         12                                    13                   1.6965

   To assess the efficiency of the fuzzy logic-based method, a dispersion criterion is
used exhibiting the sum of distances from the items of interest to the cluster midpoints
at a certain degree of membership [20].
                                                             𝑤𝑤
                           𝐽𝐽 = ∑𝑐𝑐𝑖𝑖=1 ∑𝑛𝑛𝑗𝑗=1�𝑚𝑚𝑖𝑖𝑖𝑖 � 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑�𝑣𝑣𝑖𝑖 𝑑𝑑𝑗𝑗 �,                         (1)

where 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑�𝑣𝑣𝑖𝑖 𝑑𝑑𝑗𝑗 � is the Euclidian distance between j-th item dj=(dj1, dj2, … djm,) and i-
th cluster midpoint vj=(vj1, vj2, … vjc,);
   𝑤𝑤 ∈ (1, ∞) is the exponential weight which determines fuzziness or blurriness of
clusters.
                                      𝑣𝑣11         𝑣𝑣12      ...       𝑣𝑣1𝑚𝑚
                                      𝑣𝑣21         𝑣𝑣22      ...       𝑣𝑣2𝑚𝑚
                                 𝑉𝑉 = . . .         ...      ...        ...                            (2)
                                      𝑣𝑣𝑐𝑐1        𝑣𝑣𝑐𝑐2     ...       𝑣𝑣𝑐𝑐𝑐𝑐
  and с x m is the matrix of cluster midpoint coordinates, where the elements of such
matrix are found according to the formula below:
                                        ∑𝑛𝑛           𝑤𝑤
                                         𝑗𝑗=1(𝑚𝑚𝑖𝑖𝑖𝑖 ) 𝑑𝑑𝑗𝑗𝑗𝑗
                             𝑣𝑣𝑖𝑖𝑖𝑖 =     ∑𝑛𝑛           𝑤𝑤      , 𝑘𝑘 = 1, 𝑚𝑚.                          (3)
                                           𝑗𝑗=1(𝑚𝑚𝑖𝑖𝑖𝑖 )


Having found the dispersion criterion J, we can assess the efficiency of the fuzzy logic-
based method for diabetes-induced eye-ground pathology clusterization (see Table 6
below).
Table 6. Experimental Research Estimated Results as to Eye-Ground Pathology Clusterization

                                                               Estimated            Estimated Dis-
                                                            Dispersion of        persion of Pre-set
                         Esti-                                                                          Mean
                                                            Pre-set Number       Number of Clus-
      Method          mated Dis-                                                                      Estimated
                                                            of Clusters (w/o     ters (with Lin-
                      persion                                                                         Value
                                                            Linguistic Pa-       guistic Parame-
                                                            rameters)            ters)
      Kohonen
                         0.639                                 0.831                0.841               0.770
    method
      k-means            -                                     0.742                -                   0.247
      c-means            1.000                                 0.989                1.000               0.996



6      Conclusions

The pathology average percentage is 13.88 %. In the course of the above-said research,
the clusterization method has demonstrated the best result (0.996 %), which testifies to
the applicability of such method for biomedical image recognition, as well as to its
adaptability for other fields of application, such as person authentication using the
stored in smart card eye-ground image.
   The improved recognition method, as unique person’s feature, allows to decrease
risks of data breaches compared with traditional thumbprint method, which can be rep-
licated using, for example, a modern 3D printing. The vascular system of eye-ground
is more complex, not accessed for unauthorized scanning, has much longer total length
and does not have a regular structure, which significantly improves a person authenti-
cation and decrease probability of the structure fitting.


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