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1

Czy dieta może zmieniać jakość widzenia? Wpływ spożywanych produktów na parametry wzrokowe. Cz. 2

Liguz Jessika, Jóźwik Agnieszka, Boguta Anna

Optyka

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2024

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Nr 2

56--59

PL

Artykuł stanowi kontynuację tematu opisanego w poprzednim numerze OPTYKI. W tej części omówiono, jak na ciśnienie wewnątrzgałkowe (IOP) wpływa kofeina. Badania wykazały, że jej spożycie może prowadzić do krótkotrwałego wzrostu IOP, co może mieć znaczenie szczególnie dla osób z ryzykiem chorób oczu, takich jak jaskra. Ponadto, artykuł podkreśla istotność zbilansowanej diety w utrzymaniu zdrowia wzroku. Wcześniej zauważono, że witaminy D i C wpływają pozytywnie na rozwój gałki ocznej, a witamina A poprawia jakość widzenia w różnych warunkach oświetleniowych oraz wpływa na kondycję spojówki. Kwasy tłuszczowe omega-3 regulują produkcję łez, co przyczynia się do nawilżenia oka, podczas gdy omega-6 wpływają na odporność organizmu. Jest to kluczowe dla procesów widzenia i zapobiegania chorobom oczu, takim jak zaćma. Ponadto, luteina i zeaksantyna zmniejszają obrzęk dołka i poprawiają ostrość wzroku. Wskazuje się także na negatywny wpływ nadmiernego spożycia tłuszczów nasyconych i cholesterolu na progresję krótkowzroczności. Wnioski te podkreślają znaczenie zdrowego stylu życia i odpowiedniej diety dla utrzymania dobrego stanu zdrowia oczu.

EN

The impact of caffeine on intraocular pressure (IOP) is discussed in this part. Previous studies have shown that caffeine consumption can lead to a short-term increase in intraocular pressure, which may be particularly important as risk factor for eye diseases such as glaucoma. Additionally, the article emphasizes the importance of following a balanced diet in maintaining eye health. It was previously noted that vitamins D and C have a positive effect on the development of the eyeball, while vitamin A improves the vision quality in various lighting conditions and affects the condition of the conjunctiva. Omega-3 fatty acids regulate the tear production, contributing to the hydration of the eye, while omega-6 affects the body’s immunity Itis crucial for vision processes and the prevention of eye diseases such as cataracts. Moreover, it was noticed that lutein and zeaxanthin reduce macular edema and improve visual acuity. The article also highlights the negative impact of excessive consumption of saturated fats and cholesterol on the progression of myopia. These conclusions underscore the importance of a healthy lifestyle and proper diet in maintaining good eye health.

2

Raw data from Ocular Response Analyzer applied for differentiation of normal and glaucoma patients

Jóźwik Agnieszka, Asejczyk-Widlicka Magdalena, Boszczyk Agnieszka, Kasprzak Henryk, Krzyżanowska-Berkowska Patrycja

Optica Applicata

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2020

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Vol. 50, nr 1

147--159

EN

Purpose: Presented study describes new parameters calculated from the Ocular Response Analyzer (ORA) raw data. Such an approach can increase the applicability of the ORA in ophthalmic diagnosis. Among many proposed and examined by us parameters from raw data of the air pressure and applanation curves, only a few were chosen and then applied for characterizing a selected group of patients. Methods: The study included healthy subjects in a control group and patients divided into 2 groups: suspect and glaucoma. A series of four ORA measurements were taken from each subject. The raw ORA data were numerically analyzed and new parameters were calculated from the ORA curves for each measurement. Comparative analysis was carried out for the newly proposed parameters (and original parameters from the ORA device). Results: This interesting finding is that the new parameters showed a statistically significant ability to distinguish the glaucoma suspect group from healthy and glaucomatous patients. Moreover comparable or higher repeatability than for IOPg and CH was obtained. Conclusion: Raw data from the ORA enables definition and numerical analysis of new parameters, characterizing every measurement, which can be successfully used for describing an individual eye and differentiating between some specific groups of patients.

3

Novel expert system for glaucoma identification using non-parametric spatial envelope energy spectrum with fundus images

Raghavendra U., Bhandary S. V., Gudigar A., Acharya U. R.

Biocybernetics and Biomedical Engineering

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2018

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Vol. 38, no. 1

170--180

EN

Glaucoma is the prime cause of blindness and early detection of it may prevent patients from vision loss. An expert system plays a vital role in glaucoma screening, which assist the ophthalmologists to make accurate decision. This paper proposes a novel technique for glaucoma detection using optic disk localization and non-parametric GIST descriptor. The method proposes a novel area based optic disk segmentation followed by the Radon transformation (RT). The change in the illumination levels of Radon transformed image are compensated using modified census transformation (MCT). The MCT images are then subjected to GIST descriptor to extract the spatial envelope energy spectrum. The obtained dimension of the GIST descriptor is reduced using locality sensitive discriminant analysis (LSDA) followed by various feature selection and ranking schemes. The ranked features are used to build an efficient classifier to detect glaucoma. Our system yielded a maximum accuracy (97.00%), sensitivity (97.80%) and specificity (95.80%) using support vector machine (SVM) classifier with nineteen features. Developed expert system also achieved maximum accuracy (93.62%), sensitivity (87.50%) and specificity (98.43%) for public dataset using twenty six features. The proposed method is efficient and computationally less expensive as it require only nineteen features to model a classifier for the huge dataset. Therefore the proposed method can be effectively utilized in hospitals for glaucoma screening.

4

Combination of clinical and multiresolution features for glaucoma detection and its classification using fundus images

Kausu T. R., Gopi V. P., Wahid K. A., Doma W., Niwas S. I.

Biocybernetics and Biomedical Engineering

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2018

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Vol. 38, no. 2

329--341

EN

Glaucoma is a neuro-degenerative disorder of the eye and it leads to permanent blindness when untreated or detected in the later stage. The main cause of glaucoma is the damage of the optic nerve, which occurs due to the increase of eye pressure. Hence the early detection of this disease is critical in time and which can help to prevent further vision loss. The assessment of optic nerve head using fundus images is more beneficial than the raised intra ocular pressure assessment in population-based glaucoma screening. This work proposed a novel method for glaucoma identification based on time-invariant feature cup to disk ratio and anisotropic dual-tree complex wavelet transform features. Optic disk segmentation is done by using Fuzzy C-Means clustering method and Otsu's thresholding is used for optic cup segmentation. The results show the proposed method achieved an accuracy rate of 97.67% with 98% sensitivity using a multilayer perceptron model that is considered as clinically significant when compared to the existing works.

5

Analiza kompleksowości sygnału pulsu rogówki u osób zdrowych, chorych na jaskrę i z podejrzeniem jaskry

Ząbkiewicz P. M., Placek M. M., Danielewska M. E.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2018

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Vol. 24, nr 2

65--73

PL

Puls rogówki, jako jeden z przejawów dynamiki oka, ma duży potencjał w diagnostyce jaskry. Sygnał pulsu rogówki, podobnie jak wiele innych sygnałów biologicznych, charakteryzuje się pewnym stopniem kompleksowości odzwierciedlającym zmiany w organizmie związane z wiekiem, a także występowaniem różnych zjawisk chorobowych. Metodą, która umożliwia pomiar złożoności sygnału, jest badanie entropii. W niniejszej pracy po raz pierwszy podjęto próbę sprawdzenia, czy analiza kompleksowości sygnału pulsu rogówki z zastosowaniem algorytmu Refined Composite Multiscale Fuzzy Entropy, pozwoli dokonać klasyfikacji badanych osób i określenie przynależności do grupy osób zdrowych, chorych na jaskrę albo z podejrzeniem jaskry. Analiza statystyczna klasyfikatorów uzyskanych na podstawie wyników entropii wykazała istotną różnicę w przypadku dwu par grup: z podejrzeniem jaskry vs z jaskrą oraz w przypadku zdrowych vs chorych na jaskrę. Uzyskane wyniki pokazują, że entropia wieloskalowa z sygnału pulsu rogówki może być w przyszłości nowym parametrem wspomagającym okulistów w diagnostyce jaskry.

EN

The corneal pulse, as one of the manifestations of eye dynamics, shows great potential in the glaucoma diagnosis. The corneal pulse signal, like many other biological signals, is characterized by a certain degree of complexity reflecting changes in the body and it is related to age, as well as the occurrence of various diseases. The method that allows the measurement of the signal complexity is entropy. In this study, for the first time, an attempt was made to assess, whether the complexity analysis of corneal pulse signal using Refined Composite Multiscale Fuzzy Entropy algorithm allows to classify the subjects as healthy, glaucomatous or glaucoma suspects. Statistical analysis of classifiers obtained from the results of entropy showed a significant difference in the case of two pairs of groups: with glaucoma suspects vs glaucoma patients, and healthy subjects vs glaucoma patients. The results show that multiscale entropy of the corneal pulse signal may become a new parameter supporting ophthalmologists in the diagnosis of glaucoma.

6

Robust and accurate optic disk localization using vessel symmetry line measure in fundus images

Panda R., Puhan N. B., Panda G.

Biocybernetics and Biomedical Engineering

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2017

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Vol. 37, no. 3

466--476

EN

Accurate optic disk (OD) localization is an important step in fundus image based computer-aided diagnosis of glaucoma and diabetic retinopathy. Robust OD localization becomes more challenging with the presence of common pathological variations which could alter its overall appearance. This paper presents a novel OD localization method by incorporating salient visual cues of retinal vasculature: (1) global vessel symmetry, (2) vessel component count and (3) local vessel symmetry inside OD region. In the proposed method, a new vessel symmetry line (VSL) measure is designed to demarcate the lines that divide the retinal vasculature into approximately similar halves. The initial OD center location is computed using the highest number of major blood vessel components in the skeleton image. The final OD center localization involves an iterative center of mass computation to exploit the local vessel symmetry in the OD region of interest. The proposed method shows effectiveness in diseased retinas having diverse symptoms like bright lesions, hemorrhages, and tortuous vessels that create potential ambiguity for OD localization. A total of ten publicly available retinal image databases are considered for extensive evaluation of the proposed method. The experimental results demonstrate high average OD detection accuracy of 99.49%, while achieving state-of-the-art OD localization error in all databases.

7

New Binary Hausdorff Symmetry measure based seeded region growing for retinal vessel segmentation

Panda R., Puhan N. B., Panda G.

Biocybernetics and Biomedical Engineering

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2016

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Vol. 36, no. 1

119--129

EN

Automated retinal vessel segmentation plays an important role in computer-aided diagnosis of serious diseases such as glaucoma and diabetic retinopathy. This paper contributes, (1) new Binary Hausdorff Symmetry (BHS) measure based automatic seed selection, and (2) new edge distance seeded region growing (EDSRG) algorithm for retinal vessel segmentation. The proposed BHS measure directly provides a binary symmetry decision at each pixel without the computation of continuous symmetry map and image thresholding. In a multiscale mask, the BHS measure is computed using the distance sets of opposite direction angle bins with sub-pixel resolution. The computation of the BHS measure from the Hausdorff distance sets involves point set matching based geometrical interpretation of symmetry. Then, we design a new edge distance seeded region growing (EDSRG) algorithm with the acquired seeds. The performance evaluation in terms of sensitivity, specificity and accuracy is done on the publicly available DRIVE, STARE and HRF databases. The proposed method is found to achieve state-of-the-art vessel segmentation accuracy in three retinal databases; DRIVE- sensitivity (0.7337), specificity (0.9752), accuracy (0.9539); STARE-sensitivity (0.8403), specificity (0.9547), accuracy (0.9424); and HRF-sensitivity (0.8159), specificity (0.9525), accuracy (0.9420).

8

Review of applied mathematical models for describing the behaviour of aqueous humor in eye structures

Dzierka M., Jurczak P.

International Journal of Applied Mechanics and Engineering

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2015

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Vol. 20, no. 4

757--772

EN

In the paper, currently used methods for modeling the flow of the aqueous humor through eye structures are presented. Then a computational model based on rheological models of Newtonian and non-Newtonian fluids is proposed. The proposed model may be used for modeling the flow of the aqueous humor through the trabecular meshwork. The trabecular meshwork is modeled as an array of rectilinear parallel capillary tubes. The flow of Newtonian and non-Newtonian fluids is considered. As a results of discussion mathematical equations of permeability of porous media and velocity of fluid flow through porous media have been received.

9

Non-penetrating very deep sclerectomy with a hydrophobic polymer implant in a rabbit model

Leszczyński R., Stodolak-Zych E., Gumuła T., Wieczorek J., Kosenyuk Y., Pawlicki K., Błażewicz S.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 3

23--31

EN

Purpose: The aim of the study was to evaluate the influence of an implant made of a terpolymer (PTFE-PVDF-PP) on the condition of rabbit eyes during a one year observation period. Methods: The implant in the shape of an equilateral triangle (3 mm side length) was manufactured from a thin hydrophobic porous membrane. There were evaluated 40 eyes of 20 rabbits. The animals had non-penetrating very deep sclerectomy (NPVDS) performed, with insertion of an implant in the form of a triangular thin membrane. The control group consisted of 20 eyes where the animals had NPVDS performed without implant insertion. The evaluations included the study of the anterior part of the eye together with photographic documentation. Histopathological examination of the eyes 52 weeks after NPVDS procedure has been made. The process of wound healing was comparable in both groups. Results: The evaluation of the rabbits did not reveal any acute process of intraocular inflammation. After 12 month period of observation, no statistically significant differences in the process of wound healing or status of eyes were found between the groups. An analysis of fibrous connective tissue attachment to the implant showed that its layer was not thick and did not differ significantly from the control. The procedure of very deep sclerectomy and insertion of a polymer implant were well tolerated by the rabbit eyes. Conclusions: The in vivo results indicate that the hydrophobic implant in the form of a membrane can serve as a sclera implant after further study.

10

Zmierzch tonometrii z pachymetrią?

Flasiński P.

Inżynier i Fizyk Medyczny

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2014

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Vol. 3, nr 4

214--216

PL

Prawidłowe ciśnienie gałki ocznej zależy od równowagi pomiędzy wytwarzaniem a odpływem cieczy wodnistej oka. Ciecz ta spełnia w oku podobną rolę jak krew w organizmie. U zdrowego człowieka ciśnienie oczne mieści się w przedziale 10-21 mm Hg, natomiast o nadciśnieniu mówi się, gdy wartość ciśnienia przekracza 21 mm Hg w jednym oku lub obydwu naraz. Mając na uwadze, że wysokie ciśnienie wewnątrzgałkowe jest głównym czynnikiem rozwoju jaskry, stan nadciśnienia ocznego wymaga ścisłej, regularnej kontroli oraz przeprowadzenia wszystkich niezbędnych badań w kierunku diagnostyki jaskry. O jaskrze możemy mówić, gdy dołączają się objawy neuropatii nerwu wzrokowego – uszkodzenie nerwu z ubytkami w polu widzenia. Do badania ciśnienia wewnątrzgałkowego służą tonometry. Tonometry dzielą się ze względu na zasadę pomiaru na impresyjne, aplanacyjne i bezdotykowe (powietrzne).

11

Nowa konwergentna strategia syntezy trawoprostu i bimatoprostu

Dams I., Chodyński M., Krupa M., Pietraszek A., Kutner A.

Przemysł Chemiczny

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2013

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T. 92, nr 4

522-526

12

Automatic graph cut based segmentation of retinal optic disc by incorporating blood vessel compensation

Salazar-Gonzalez A., Li Y, Liu X.

Journal of Artificial Intelligence and Soft Computing Research

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2012

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Vol. 2, No. 3

235--245

EN

Glaucoma is one of the main causes of blindness worldwide. Periodical retinal screening is highly recommended in order to detect any sign of the disease and apply the appropriated treatment. Different systems for the analysis of retinal images have been designed in order to assist this process. The segmentation of the optic disc is an important step in the development of a retinal screening system. In this paper we present an unsupervised method for the segmentation of the optic disc. The main obstruction in the optic disc segmentation process is the presence of blood vessels breaking the continuity of the object. While many other methods have addressed this problem trying to eliminate the vessels, we have incorporated the blood vessel information into our formulation. The blood vessels inside of the optic disc are used to give continuity to the object to segment. Our approach is based on the graph cut technique, where the graph is constructed by considering the relationship between neighbouring pixels and by the likelihood of them belonging to the foreground and background from prior information. Our method was tested on two public datasets, DIARETDB1 and DRIVE. The performance of our method was measured by calculating the overlapping ratio (Oratio), sensitivity and the mean absolute distance (MAD) with respect to the manually labeled images.

13

Support vector clustering algorithm for identification of glaucoma in ophthalmology

Stąpor K.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2006

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Vol. 54, nr 1

139-141

EN

This paper presents the improved version of the classification system for supporting glaucoma diagnosis in ophthalmology. In this paper we propose the new segmentation step based on the support vector clustering algorithm which enables better classification performance. Key words: clustering, image segmentation, kernel-based learning, glaucoma.

14

Laseroterapia w leczeniu jaskry

Misiuk-Hojło M., Woźniak Z., Stępniewska A.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2005

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Vol. 11, nr 3-4

43-46

PL

Jaskra jest to grupa chorób prowadzących do utraty wzroku w wyniku uszkodzenia nerwu wzrokowego. Istnieje wiele laserowych narzędzi stosowanych do kontrolowania podwyższonego ciśnienia wewnątrzgałkowego, będącego głównym objawem jaskry, poprzez hamowanie procesu produkcji cieczy wodnistej lub odprowadzanie jej nadmiaru.

EN

Glaucoma is an eye condition characterlsted by loss of vision due to demage of the optic nerve. They are numerous laser instruments which are used to control intraocular eye pressure in glaucoma, either by reducing the production of aqueus or by easing the escape of aqueus from the eye.

15

Neural network classification of eye-cup region in fundus eye images

Stąpor K., Mazurkiewicz M., Rzendkowski M.

Studia Informatica

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2004

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Vol. 25, nr 1

47-56

EN

In this paper the new method for classification of digital fundus eye images into normal and glaucomatous ones is proposed. The classifier used is based on multi-layer perceptron. The performance of the classifier is 94,77%. The obtained results arę encouraging.

PL

W artykule przedstawiono nowa metodę klasyfikacji obrazów dna oka uzyskiwanych z funduskamery na jaskrowe i zdrowe. W roli klasyfikatora zastosowano wielowarstwowy perceptron. Wyniki eksperymentu wykazały bardzo wysoką sprawność procedury klasyfikacyjnej: 94,77%. Otrzymane rezultaty są zachęcające.

16

Locating eye-cup region in fundus eye images for glaucoma diagnosing

Stąpor K., Pawlaczyk L., Trojnar M.

Studia Informatica

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2004

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Vol. 25, nr 1

35-46

EN

In this paper a new algorithm of the eye cup segmentation from fundus eye images (fei) is proposed. It is based on an adaptive dynamie thresholding techniąue performed on a channel a* of a L*a*b* color model. The obtained contour of eye-cup region will be used in a classification procedurę supporting ophthalmologist in glaucoma diagnosing.

PL

W artykule prezentowany jest nowy algorytm segmentacji cyfrowych obrazów dna oka (fei). Jest on oparty na adaptacyjnym progowaniu wykonywanym na kanale a* modelu kolorów L*a*b*. Uzyskany kontur wnęki naczyniowej jest używany w procedurze klasyfikacji wspomagającej lekarza okulistę w diagnostyce jaskry.

17

Classification of fundus eye images using support vector machines for supporting glaucoma diagnosis

Stąpor K., Brueckner A.

Studia Informatica

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2004

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Vol. 25, nr 3

49-59

EN

In this paper the new method for automatic classification of fundus eye images into normal and glaucomatous ones is proposed. The cup region is automatically segmented from fundus eye images taken from classical fundus camera. The proposed method makes use of support vector machines classifier with Gaussian kernel. The mean sensitivity is 85 %, while specificity 90%.

PL

W artykule przedstawiono nową metodę automatycznej klasyfikacji cyfrowych obrazów dna oka na normalne i jaskrowe. Obszar wnęki naczyniowej zostaje automatycznie wysegmentowany na obrazie dna oka pozyskanego z klasycznej funduskamery. Zaproponowana metoda klasyfikacji wykorzystuje maszyny wektorów podpierających z jądrem Gaussowskim. Średnia czułość metody wynosi 85%, a specyficzność 90%.

18

Automatic segmentation of fundus eye images using fuzzy clustering supporting glaucoma diagnosing

Stąpor K., Brueckner A.

Studia Informatica

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2004

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Vol. 25, nr 3

61-70

EN

In this paper the new method for automatic segmentation of cup region from fundus eye images taken from classical fundus camera. The proposed method which is based on fuzzy clustering algorithm is a first step in automatic classification of fundus eye images into normal and glaucomatous ones.

PL

W artykule przedstawiono nową metodę automatycznej segmentacji wnęki naczyniowej na cyfrowych obrazach dna oka. Metoda wykorzystuje klasteryzację rozmytą i stanowi pierwszy etap w systemie automatycznej klasyfikacji obrazów dna oka na jaskrowe i normalne.

19

Automatic analysis of fundus eye images using mathematical morphology and neural networks for supporting glaucoma diagnosis

Stąpor K., Świtoński A.

Machine Graphics and Vision

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2004

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Vol. 13, No. 1/2

65-78

EN

In this paper a new method for automatic segmentation and classification of fundus eye images (fei) into normal and glaucomatous ones is proposed. The segmentation of the cup region from the fei makes use of a morphological watershed transformation with markers imposed. New features for quantitative cup evaluation are found based on genetic algorithms with the proposed new fitness function. The computed features are then used in a classification procedure which is based on a multilayer perceptron. The mean sensitivity is 90%, while the mean specificity reaches 85%. The results obtained are encouraging.

20

Support vector machine classification of fundus eye images for glaucoma diagnostig

Stąpor K., Bruckner A.

Archiwum Informatyki Teoretycznej i Stosowanej

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2004

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T. 16, z. 4

245-255

EN

In this paper the new method for automatic segmentation of fundus eye images are proposed: one for the detection of microaneurysms, the second for the detection of blood vessels. Both rely on tools from mathematical, grayscale morphology. The proposed method can be integrated in a tool for diagnosis of diabetic retinopathy which is under development.

PL

W artykule przedstawiono nowe metody automatycznej segmentacji obrazów dna oka pozyskanych z funduskamery: jedna dla detekcji mikroaneurazymów, druga dla naczyń krwionośnych na siatkówce oka. Metoda detekcji mikroaneurazymów składa się z następujących kroków: 1) przetwarzanie wstępne, 2) detekcja markerów dla transformaty wodnej, 3) transformata wodna, 4) klasyfikacja. W celu automatycznej detekcji markerów wewnętrznych dla transformaty wodnej zdefiniowano nowe przekształcenie trafi-nie-trafi w morfologii wieloodcieniowej. Uzyskana średnia sprawność metody wynosi 89,4% i jest wyższa od wyników uzyskanych w metodach poprzednich (84%). Metoda detekcji naczyń krwionośnych składa się z następujących kroków: 1) lokalna poprawa kontrastu, 2) odszumianie, 3) detekcja naczyń, 4)klasyfikacja. W celu odszumienia zastosowano operacje złożone ze specjalnie zaprojektowanych operacji dylatacji i erozji wieloodcieniowej. Sama detekcja naczyń wykorzystuje operację czubek-kapelusza. Opracowane algorytmy detekcji stanowić będą podstawowe moduły systemu komputerowego wspomagającego diagnozowanie jak również monitorowanie tej retinopatii cukrzycowej.