Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Knee Surg Sports Traumatol Arthrosc ; 30(1): 260-269, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33609151

RESUMO

PURPOSE: The purpose of this study was to assess the quality of the bone tissue microstructure from the footprints of the anterior cruciate ligament (ACL) and its impact on late follow-up outcomes in patients who undergo anterior cruciate ligament reconstruction (ACLR). METHODS: The records of 26 patients diagnosed with a completely torn ACL who underwent ACLR were collected. During the surgery performed using the Felmet method, bone blocks from the native ACL footprints were collected. The primary measurements of the bone microstructure were made using a microtomographic scanner. In late follow-up examinations, a GNRB arthrometer was used. RESULTS: There was no significant difference in the bone microstructure assessed using micro-CT histomorphometric data according to the blood test results, plain radiographs, age or anthropometric data. There was no difference in the bone volume/total volume ratio or trabecular thickness in the area of the native ACL footprints. Routine preoperative examinations were not relevant to the quality of the bone microstructure. The elapsed time from an ACL injury to surgery had no relevance to the results of arthrometry. CONCLUSION: The similarities in the microstructure of bone blocks from ACL footprints from the femur and tibia allow the variable use of these blocks to stabilize grafts in the Felmet method. The bone microstructure is not dependent on the time from injury to surgery. Histomorphometric values of the structure of the femoral and tibial ACL footprints have no impact on the long-term stability of the operated knee joint. TRIAL REGISTRATION: The approval of the Bioethics Committee of the Silesian Medical Chamber in Katowice, Poland (resolution 16/2014) was given for this research. LEVEL OF EVIDENCE: II.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/diagnóstico por imagem , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
2.
Sensors (Basel) ; 22(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36560234

RESUMO

Modern systems of intelligent sensors commonly use radio data transmission. Hand movement acquisition with the use of inertial sensors requires the processing and transmission of a relatively large amount of data, which may be associated with a significant load on the network structure. Network traffic limitation, without losing the quality of monitoring parameters from the sensor system, is therefore important for the functioning of the radio network which integrates both the teletransmission sensor system and the data acquisition server. The paper presents a wearable solution for hand movement acquisition, which uses data transmission in the Wi-Fi standard and contains 16 MEMS (Micro Electro Mechanical System) sensors. An adaptive algorithm to control radio data transmission for the sensor system has been proposed. The algorithm implemented in the embedded system controls the change of the frame length, the length of the transmission frame and the frequency of its sending, which reduces the load on the network router. The use of the algorithm makes it possible to reduce the power consumption by the sensor system by up to 19.9% and to limit the number of data transferred by up to about 91.6%, without losing the quality of the monitored signal. The data analysis showed no statistically significant differences (p > 0.05) between the signal reconstructed from the complete data and processed by the algorithm.


Assuntos
Algoritmos , Sistemas Microeletromecânicos , Movimento , Computadores
3.
J Opt Soc Am A Opt Image Sci Vis ; 32(8): 1446-53, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26367287

RESUMO

Pulsation in the blood vessels of the eye has a big impact on the dynamics of the entire eyeball and its individual elements. Blood pulsation in the retina can be recorded by the pupil, whose size is also subject to dynamic changes. The study involved synchronous measurements of pupil size using a high-speed camera, and blood pulsation using a pulse oximeter placed on the ear lobe. In addition, there were no metrologically significant differences in the phase shift between the average brightness of the individual pupil quadrants. Blood pulsation in other ocular tissues can affect the dynamics of the optical properties of the eye. As demonstrated in this paper, it affects the pupil behavior and its parameters to a considerable extent.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Raios Infravermelhos , Fotometria/métodos , Fluxo Pulsátil/fisiologia , Pulso Arterial/métodos , Pupila/fisiologia , Algoritmos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Biomed Eng Online ; 13: 16, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24528923

RESUMO

INTRODUCTION: In many practical aspects of ophthalmology, it is necessary to assess the severity degree of glaucoma in cases where, for various reasons, it is impossible to perform a visual field test - static perimetry. These are cases in which the visual field test result is not reliable, e.g. advanced AMD (Age-related Macular Degeneration). In these cases, there is a need to determine the severity of glaucoma, mainly on the basis of optic nerve head (ONH) and retinal nerve fibre layer (RNFL) structure. OCT is one of the diagnostic methods capable of analysing changes in both, ONH and RNFL in glaucoma. MATERIAL AND METHOD: OCT images of the eye fundus of 55 patients (110 eyes) were obtained from the SOCT Copernicus (Optopol Tech. SA, Zawiercie, Poland). The authors proposed a new method for automatic determination of the RNFL (retinal nerve fibre layer) and other parameters using: mathematical morphology and profiled segmentation based on morphometric information of the eye fundus. A quantitative ratio of the quality of the optic disk and RNFL - BGA (biomorphological glaucoma advancement) was also proposed. The obtained results were compared with the results obtained from a static perimeter. RESULTS: Correlations between the known parameters of the optic disk as well as those suggested by the authors and the results obtained from static perimetry were calculated. The result of correlation with the static perimetry was 0.78 for the existing methods of image analysis and 0.86 for the proposed method. Practical usefulness of the proposed ratio BGA and the impact of the three most important features on the result were assessed. The following results of correlation for the three proposed classes were obtained: cup/disk diameter 0.84, disk diameter 0.97 and the RNFL 1.0. Thus, analysis of the supposed visual field result in the case of glaucoma is possible based only on OCT images of the eye fundus. CONCLUSIONS: The calculations and analyses performed with the proposed algorithm and BGA ratio confirm that it is possible to calculate supposed mean defect (MD) of the visual field test based on OCT images of the eye fundus.


Assuntos
Glaucoma/fisiopatologia , Processamento de Imagem Assistida por Computador/métodos , Tomografia de Coerência Óptica/métodos , Campos Visuais , Automação , Glaucoma/diagnóstico , Humanos
5.
Biomed Eng Online ; 13: 113, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25103039

RESUMO

INTRODUCTION: Among the currently known imaging methods, there exists hyperspectral imaging. This imaging fills the gap in visible light imaging with conventional, known devices that use classical CCDs. A major problem in the study of the skin is its segmentation and proper calibration of the results obtained. For this purpose, a dedicated automatic image analysis algorithm is proposed by the paper's authors. MATERIAL AND METHOD: The developed algorithm was tested on data acquired with the Specim camera. Images were related to different body areas of healthy patients. The resulting data were anonymized and stored in the output format, source dat (ENVI File) and raw. The frequency λ of the data obtained ranged from 397 to 1030 nm. Each image was recorded every 0.79 nm, which in total gave 800 2D images for each subject. A total of 36'000 2D images in dat format and the same number of images in the raw format were obtained for 45 full hyperspectral measurement sessions. As part of the paper, an image analysis algorithm using known analysis methods as well as new ones developed by the authors was proposed. Among others, filtration with a median filter, the Canny filter, conditional opening and closing operations and spectral analysis were used. The algorithm was implemented in Matlab and C and is used in practice. RESULTS: The proposed method enables accurate segmentation for 36'000 measured 2D images at the level of 7.8%. Segmentation is carried out fully automatically based on the reference ray spectrum. In addition, brightness calibration of individual 2D images is performed for the subsequent wavelengths. For a few segmented areas, the analysis time using Intel Core i5 CPU RAM M460@2.5GHz 4GB does not exceed 10 s. CONCLUSIONS: The obtained results confirm the usefulness of the applied method for image analysis and processing in dermatological practice. In particular, it is useful in the quantitative evaluation of skin lesions. Such analysis can be performed fully automatically without operator's intervention.


Assuntos
Dermatologia/métodos , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Pele/anatomia & histologia , Algoritmos , Calibragem , Humanos , Modelos Teóricos
6.
Biomed Eng Online ; 13: 48, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24755213

RESUMO

INTRODUCTION: Fixed orthodontic appliances, despite years of research and development, still raise a lot of controversy because of its potentially destructive influence on enamel. Therefore, it is necessary to quantitatively assess the condition and therein the thickness of tooth enamel in order to select the appropriate orthodontic bonding and debonding methodology as well as to assess the quality of enamel after treatment and clean-up procedure in order to choose the most advantageous course of treatment. One of the assessment methods is computed tomography where the measurement of enamel thickness and the 3D reconstruction of image sequences can be performed fully automatically. MATERIAL AND METHOD: OCT images of 180 teeth were obtained from the Topcon 3D OCT-2000 camera. The images were obtained in vitro by performing sequentially 7 stages of treatment on all the teeth: before any interference into enamel, polishing with orthodontic paste, etching and application of a bonding system, orthodontic bracket bonding, orthodontic bracket removal, cleaning off adhesive residue. A dedicated method for the analysis and processing of images involving median filtering, mathematical morphology, binarization, polynomial approximation and the active contour method has been proposed. RESULTS: The obtained results enable automatic measurement of tooth enamel thickness in 5 seconds using the Core i5 CPU M460 @ 2.5GHz 4GB RAM. For one patient, the proposed method of analysis confirms enamel thickness loss of 80 µm (from 730 ± 165 µm to 650 ± 129 µm) after polishing with paste, enamel thickness loss of 435 µm (from 730 ± 165 µm to 295 ± 55 µm) after etching and bonding resin application, growth of a layer having a thickness of 265 µm (from 295 ± 55 µm to 560 ± 98 µm after etching) which is the adhesive system. After removing an orthodontic bracket, the adhesive residue was 105 µm and after cleaning it off, the enamel thickness was 605 µm. The enamel thickness before and after the whole treatment decreased by about 125 µm. CONCLUSIONS: This paper presents an automatic quantitative method for the assessment of tooth enamel thickness. This method has proven to be an effective diagnostic tool that allows evaluation of the surface and cross section of tooth enamel after orthodontic treatment with fixed thin-arched braces and proper selection of the methodology and course of treatment.


Assuntos
Braquetes , Esmalte Dentário , Processamento de Imagem Assistida por Computador/métodos , Tomografia de Coerência Óptica/métodos , Algoritmos , Automação , Esmalte Dentário/citologia , Esmalte Dentário/crescimento & desenvolvimento , Humanos , Braquetes Ortodônticos , Propriedades de Superfície
7.
Biomed Eng Online ; 13: 47, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24755183

RESUMO

INTRODUCTION: Hyperspectral imaging has been used in dermatology for many years. The enrichment of hyperspectral imaging with image analysis broadens considerably the possibility of reproducible, quantitative evaluation of, for example, melanin and haemoglobin at any location in the patient's skin. The dedicated image analysis method proposed by the authors enables to automatically perform this type of measurement. MATERIAL AND METHOD: As part of the study, an algorithm for the analysis of hyperspectral images of healthy human skin acquired with the use of the Specim camera was proposed. Images were collected from the dorsal side of the hand. The frequency λ of the data obtained ranged from 397 to 1030 nm. A total of 4'000 2D images were obtained for 5 hyperspectral images. The method proposed in the paper uses dedicated image analysis based on human anthropometric data, mathematical morphology, median filtration, normalization and others. The algorithm was implemented in Matlab and C programs and is used in practice. RESULTS: The algorithm of image analysis and processing proposed by the authors enables segmentation of any region of the hand (fingers, wrist) in a reproducible manner. In addition, the method allows to quantify the frequency content in different regions of interest which are determined automatically. Owing to this, it is possible to perform analyses for melanin in the frequency range λE∈(450,600) nm and for haemoglobin in the range λH∈(397,500) nm extending into the ultraviolet for the type of camera used. In these ranges, there are 189 images for melanin and 126 images for haemoglobin. For six areas of the left and right sides of the little finger (digitus minimus manus), the mean values of melanin and haemoglobin content were 17% and 15% respectively compared to the pattern. CONCLUSIONS: The obtained results confirmed the usefulness of the proposed new method of image analysis and processing in dermatology of the hand as it enables reproducible, quantitative assessment of any fragment of this body part. Each image in a sequence was analysed in this way in no more than 100 ms using Intel Core i5 CPU M460 @2.5 GHz 4 GB RAM.


Assuntos
Mãos , Processamento de Imagem Assistida por Computador/métodos , Imagem Molecular/métodos , Pele/metabolismo , Algoritmos , Automação , Hemoglobinas/metabolismo , Humanos , Melaninas/metabolismo
8.
Biomed Eng Online ; 13: 55, 2014 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-24885525

RESUMO

INTRODUCTION: Contemporary ophthalmology knows many methods of measuring intraocular pressure, namely the methods of non-contact and impression applanation tonometry. In non-contact applanation tonometers, e.g. the Corvis, the corneal flattening is caused by an air puff. Image registration of the corneal deflection performed by a tonometer enables to determine other interesting biomechanical parameters of the eye, which are not available in the tonometer. The measurement of new selected parameters is presented in this paper. MATERIAL AND METHOD: Images with an M × N × I resolution of 200 × 576 × 140 pixels were acquired from the Corvis device in the source recording format *.cst. A total of 13'400 2D images of patients examined routinely in the Clinical Department of Ophthalmology, in District Railway Hospital in Katowice, Poland, were analysed in accordance with the Declaration of Helsinki. A new method has been proposed for the analysis of corneal deflection images in the Corvis tonometer with the use of the Canny edge detection method, mathematical morphology methods and context-free operations. RESULTS: The resulting image analysis tool allows determination of the response of the cornea and the entire eyeball to an air puff. The paper presents the method that enables the measurement of the amplitude of curvature changes in the frequency range from 150 to 500 Hz and automatic designation of the eyeball movement direction. The analysis of these data resulted in 3 new features of dynamics of the eye reaction to an air puff. Classification of these features enabled to propose 4 classes of deformation. The proposed algorithm allows to obtain reproducible results fully automatically at a time of 5 s per patient using the Core i5 CPU M460 @ 2.5GHz 4GB of RAM. CONCLUSIONS: The paper presents the possibility of using a profiled algorithm of image analysis, proposed by the authors, to measure additional cornea deformation parameters. The new tool enables automatic measurement of the additional new parameters when using the Corvis tonometer. A detailed clinical examination based on this method will be presented in subsequent papers.


Assuntos
Córnea , Processamento de Imagem Assistida por Computador , Fenômenos Mecânicos , Tonometria Ocular , Adolescente , Adulto , Algoritmos , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Radiat Environ Biophys ; 53(1): 203-10, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24213588

RESUMO

The aim of this work was to determine the concentrations and properties of free radicals in piperacillin, ampicillin, and crystalline penicillin after gamma irradiation. The radicals were studied by electron paramagnetic resonance (EPR) spectroscopy using an X-band spectrometer (9.3 GHz). Gamma irradiation was performed at a dose of 25 kGy. One- and two-exponential functions were fitted to the experimental data, in order to assess the influence of the antibiotics' storage time on the measured EPR lines. After gamma irradiation, complex EPR lines were recorded confirming the presence of a large number of free radicals formed during the irradiation. For all tested antibiotics, concentrations of free radicals and parameters of EPR spectra changed with storage time. The results obtained demonstrate that concentration of free radicals and other spectroscopic parameters can be used to select the optimal parameters of radiation sterilization of ß-lactam antibiotics. The most important parameters are the constants τ (τ (1(A),(I)) and τ (2(A),(I))) and K (K (0(A),(I)), K (1(A),(I)), K (2(A),(I))) of the exponential functions that describe free radicals decay during samples storage.


Assuntos
Antibacterianos/química , Radicais Livres/análise , Raios gama , Ampicilina/química , Microscopia Eletrônica de Transmissão por Filtração de Energia , Penicilinas/química , Piperacilina/química , Esterilização
10.
Cell Tissue Bank ; 15(3): 307-17, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23999650

RESUMO

Nowadays, there are four types of meniscal allografts known: fresh, cryopreserved, deep-frozen and lyophilized ones but only two of them are widely used in clinical practice. Use of different types of meniscal allografts still remains controversial due to preparation method, their biomechanical properties as well as cost which is connected with processing and storage. The main aim of this review is to present the current status of knowledge concerning meniscal allograft preservation and sterilization, especially the advantages and disadvantages of each method. Authors wanted to show a broad spectrum of methods used and conceptions presented by other authors. The second aim is to gather available information about meniscal preservation and sterilization methods in one paper. Deep-frozen and cryopreserved meniscal allografts are the most frequently used ones in the clinical practice. The use of fresh grafts stays controversial but also has many followers. Lyophilized grafts in turn are not applied at present due to some serious drawbacks including reduction of tensile strength, poor rehydration, graft shrinkage and post-transplantation joint effusion as well as increased risk of meniscal size reduction. An application of sterilizing agents make the meniscal allograft free from the bacteria and viruses, but also it may cause serious structure changes. Therefore, choosing just one ideal method of meniscal allograft preservation and sterilization is complicated and should be based on broad knowledge and experience of surgeon performing the transplantation.


Assuntos
Criopreservação , Meniscos Tibiais/cirurgia , Esterilização , Transplante Homólogo , Animais , Criopreservação/métodos , Humanos , Articulação do Joelho/patologia , Esterilização/métodos , Transplante Homólogo/métodos
11.
Biomed Eng Online ; 12: 74, 2013 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-23879837

RESUMO

INTRODUCTION: Pseudoexfoliation syndrome (PEX) is a systemic disease involving the accumulation of pathological material deposits in the tissues of the anterior segment of the eye. The problem of modern ophthalmology is a quantitative assessment of the severity of PEX in the diagnosis and evaluation of the treatment progress in patients. MATERIAL AND METHOD: For the purposes of this study, 52 images of the anterior segment of the eye with the resolution of M × N = 1280 × 960 pixels were obtained in jpg format using the slit lamp CSO 450-SL. The patients were aged 50-80 and were recruited from Poland. All patients who participated in the study provided written informed consent after explanation of the nature and possible consequences of the study. The image analysis method proposed by the authors contains the calculation of the direction field, setting a straight perpendicular line passing through each pixel of the edge of the pupil, the calculation of the intersection of straight lines in order to determine the central point of the pupil position, the detection of the contour of PEX and the outer border of the iris with the use of the polar coordinate system. All analyzed parameters were set automatically with one exception parameter chosen manually depending on the slit lamp type. RESULTS: A fully automatic measurement of PEX was carried out with the proposed method. Quantitative results enable to perform reproducible tests independently of the research centre. Owing to the image analysis method proposed by the authors, it is possible to obtain results in no more than 1 second on the Intel Core 2 Quad CPU 2.50 GHz with a measurement error below 3%. Other known methods of image analysis and processing that are compared in this paper give results with a greater error (4-35%) which depends on the degree of magnification (×6, ×16, ×20) and are not fully automatic. CONCLUSIONS: The methods of image analysis and processing enable a quantitative, repeatable and automatic measurement of the severity and progress of PEX syndrome. They support medical diagnosis and automatic archiving of results.


Assuntos
Síndrome de Exfoliação/diagnóstico , Olho , Luz , Oftalmologia/métodos , Idoso , Idoso de 80 Anos ou mais , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade
12.
Biomed Eng Online ; 12: 117, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24224964

RESUMO

INTRODUCTION: This paper describes a method for automatic analysis of the choroid in OCT images of the eye fundus in ophthalmology. The problem of vascular lesions occurs e.g. in a large population of patients having diabetes or macular degeneration. Their correct diagnosis and quantitative assessment of the treatment progress are a critical part of the eye fundus diagnosis. MATERIAL AND METHOD: The study analysed about 1'000 OCT images acquired using SOCT Copernicus (Optopol Tech. SA, Zawiercie, Poland). The proposed algorithm for image analysis enabled to analyse the texture of the choroid portion located beneath the RPE (Retinal Pigment Epithelium) layer. The analysis was performed using the profiled algorithm based on morphological analysis and texture analysis and a classifier in the form of decision trees. RESULTS: The location of the centres of gravity of individual objects present in the image beneath the RPE layer proved to be important in the evaluation of different types of images. In addition, the value of the standard deviation and the number of objects in a scene were equally important. These features enabled classification of three different forms of the choroid that were related to retinal pathology: diabetic edema (the classification gave accuracy ACC1 = 0.73), ischemia of the inner retinal layers (ACC2 = 0.83) and scarring fibro vascular tissue (ACC3 = 0.69). For the cut decision tree the results were as follows: ACC1 = 0.76, ACC2 = 0.81, ACC3 = 0.68. CONCLUSIONS: The created decision tree enabled to obtain satisfactory results of the classification of three types of choroidal imaging. In addition, it was shown that for the assumed characteristics and the developed classifier, the location of B-scan does not significantly affect the results. The image analysis method for texture analysis presented in the paper confirmed its usefulness in choroid imaging. Currently the application is further studied in the Clinical Department of Ophthalmology in the District Railway Hospital in Katowice, Medical University of Silesia, Poland.


Assuntos
Doenças da Coroide/diagnóstico , Fundo de Olho , Processamento de Imagem Assistida por Computador/métodos , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Idoso , Algoritmos , Automação , Criança , Humanos , Pessoa de Meia-Idade , Adulto Jovem
13.
Biomed Eng Online ; 12: 40, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23663502

RESUMO

INTRODUCTION: This paper presents the problem of automatic measurement of the iridocorneal angle in tomographic images of the anterior segment of the eye. It includes the results of the comparison of well-known methods for measuring the iridocorneal angle with new methods, proposed in this paper. All these methods concern tomographic image analysis and processing. MATERIAL AND METHOD: In total, approximately 100'000 tomographic images (from about 6'000 patients) were analysed. They were obtained using two devices: SOCT Copernicus (Optopol Tech. SA, Zawiercie, Poland) and Visante OCT (Carl Zeiss Meditec, Inc, Dublin, California, USA). The patients, aged 12 to 78 years with varying degrees of the iridocorneal angle pathology, were from the region of Silesia, Poland. The images were in DICOM or RAW formats and analysed in the software developed by the authors for the purposes of this study. RESULTS: The results indicate that the measurement method proposed by the authors, which is based on the calculation of the minimum distance between the iris and the cornea in the adopted area, is the most accurate. For this method sensitivity was 0.88, specificity 0.89 and the area under the Receiver Operating Characteristic curve (AUC) was 0.88. The other known methods for measuring the iridocorneal angle gave worse results, that is, for example, for the measurement of the distance between the iris and the cornea AUC = 0.87, sensitivity = 0.86 and specificity = 0.71. For another well-known method of measuring the iridocorneal angle AUC = 0.77, sensitivity = 0.82 and specificity = 0.61. CONCLUSIONS: The study proved that the proposed method of measuring the minimum distance between the iris and the cornea within the adopted area is the most effective in the classification of the iridocorneal angle in patients with a high degree of pathology of all the compared measurement methods based on tomographic images. However, it requires fully automated measurement.


Assuntos
Córnea/citologia , Processamento de Imagem Assistida por Computador/métodos , Iris/citologia , Tomografia de Coerência Óptica/métodos , Algoritmos , Humanos , Software , Tomografia de Coerência Óptica/instrumentação
14.
Biomed Eng Online ; 12: 68, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23835039

RESUMO

INTRODUCTION: The analysis of polyacrylamide gels is currently carried out manually or automatically. In the automatic method, there are limitations related to the acceptable degree of distortion of lane and band continuity. The available software cannot deal satisfactorily with this type of situations. Therefore, the paper presents an original image analysis method devoid of the aforementioned drawbacks. MATERIAL: This paper examines polyacrylamide gel images from Li-Cor DNA Sequencer 4300S resulting from the use of the electrophoretic separation of DNA fragments. The acquired images have a resolution dependent on the length of the analysed DNA fragments and typically it is MG×NG=3806×1027 pixels. The images are saved in TIFF format with a grayscale resolution of 16 bits/pixel. The presented image analysis method was performed on gel images resulting from the analysis of DNA methylome profiling in plants exposed to drought stress, carried out with the MSAP (Methylation Sensitive Amplification Polymorphism) technique. RESULTS: The results of DNA polymorphism analysis were obtained in less than one second for the Intel Core™ 2 Quad CPU Q9300@2.5GHz, 8GB RAM. In comparison with other known methods, specificity was 0.95, sensitivity = 0.94 and AUC (Area Under Curve) = 0.98. CONCLUSIONS: It is possible to carry out this method of DNA polymorphism analysis on distorted images of polyacrylamide gels. The method is fully automatic and does not require any operator intervention. Compared with other methods, it produces the best results and the resulting image is easy to interpret. The presented method of measurement is used in the practical analysis of polyacrylamide gels in the Department of Genetics at the University of Silesia in Katowice, Poland.


Assuntos
DNA/genética , DNA/isolamento & purificação , Eletroforese em Gel de Poliacrilamida/métodos , Polimorfismo Genético , Automação , Análise de Sequência de DNA
15.
Biomed Eng Online ; 12: 51, 2013 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-23758786

RESUMO

BACKGROUND: Efficacy and safety of various treatments using fractional laser or radiofrequency depend, to a large extent, on precise movement of equipment head across the patient's skin. In addition, they both depend on uniform distribution of emitted pulses throughout the treated skin area. The pulses should be closely adjacent but they should not overlap. Pulse overlapping results in amplification of irradiation dose and carries the danger of unwanted effects. METHODS: Images obtained in infrared mode (Flir SC5200 thermovision camera equipped with photon detector) were entered into Matlab environment. Thermal changes in the skin were forced by CO2RE laser. Proposed image analysis and processing methods enable automatic recognition of CO2RE laser sites of action, making possible to assess the correctness of performed cosmetic procedures. RESULTS: 80 images were acquired and analyzed. Regions of interest (ROI) for the entire treatment field were determined automatically. In accordance with the proposed algorithm, laser-irradiated Li areas (ROI) were determined for the treatment area. On this basis, error values were calculated and expressed as percentage of area not covered by any irradiation dose (δo) and as percentage area which received double dose (δz). The respective values for the analyzed images were δo=17.87±10.5% and δz=1.97±1.5%, respectively. CONCLUSIONS: The presented method of verifying the correctness of performing low-invasive esthetic medical (cosmetic) procedures has proved itself numerous times in practice. Advantages of the method include: automatic determination of coverage error values δo and δz, non-invasive, sterile and remote-controlled thermovisual mode of measurements, and possibility of assessing dynamics of patient's skin temperature changes.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Cirurgia Assistida por Computador/métodos , Cirurgia Plástica/métodos , Algoritmos , Humanos , Raios Infravermelhos , Lasers , Temperatura Cutânea
16.
Biomed Eng Online ; 12: 60, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23815984

RESUMO

INTRODUCTION: The paper presents the methodology and the algorithm developed to analyze sonar images focused on fish detection in small water bodies and measurement of their parameters: volume, depth and the GPS location. The final results are stored in a table and can be exported to any numerical environment for further analysis. MATERIAL AND METHOD: The measurement method for estimating the number of fish using the automatic robot is based on a sequential calculation of the number of occurrences of fish on the set trajectory. The data analysis from the sonar concerned automatic recognition of fish using the methods of image analysis and processing. RESULTS: Image analysis algorithm, a mobile robot together with its control in the 2.4 GHz band and full cryptographic communication with the data archiving station was developed as part of this study. For the three model fish ponds where verification of fish catches was carried out (548, 171 and 226 individuals), the measurement error for the described method was not exceeded 8%. SUMMARY: Created robot together with the developed software has features for remote work also in the variety of harsh weather and environmental conditions, is fully automated and can be remotely controlled using Internet. Designed system enables fish spatial location (GPS coordinates and the depth). The purpose of the robot is a non-invasive measurement of the number of fish in water reservoirs and a measurement of the quality of drinking water consumed by humans, especially in situations where local sources of pollution could have a significant impact on the quality of water collected for water treatment for people and when getting to these places is difficult. The systematically used robot equipped with the appropriate sensors, can be part of early warning system against the pollution of water used by humans (drinking water, natural swimming pools) which can be dangerous for their health.


Assuntos
Peixes , Robótica , Som , Qualidade da Água , Algoritmos , Animais , Automação , Fenômenos Químicos , Meio Ambiente , Processamento de Imagem Assistida por Computador , Densidade Demográfica
17.
Biomed Eng Online ; 11: 91, 2012 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-23190930

RESUMO

INTRODUCTION: This paper shows the influence of a measurement method of features in the diagnosis of Hashimoto's disease. Sensitivity of the algorithm to changes in the parameters of the ROI, namely shift, resizing and rotation, has been presented. The obtained results were also compared to the methods known from the literature in which decision trees or average gray level thresholding are used. MATERIAL: In the study, 288 images obtained from patients with Hashimoto's disease and 236 images from healthy subjects have been analyzed. For each person, an ultrasound examination of the left and right thyroid lobe in transverse and longitudinal sections has been performed. METHOD: With the use of the developed algorithm, a discriminant analysis has been conducted for the following five options: linear, diaglinear, quadratic, diagquadratic and mahalanobis. The left and right thyroid lobes have been analyzed both together and separately in transverse and longitudinal sections. In addition, the algorithm enabled to analyze specificity and sensitivity as well as the impact of sensitivity of ROI shift, repositioning and rotation on the measured features. RESULTS AND SUMMARY: The analysis has shown that the highest accuracy was obtained for the longitudinal section (LD) with the method of linear, yielding sensitivity = 76%, specificity = 95% and accuracy ACC = 84%. The conducted sensitivity assessment confirms that changes in the position and size of the ROI have little effect on sensitivity and specificity. The analysis of all cases, that is, images of the left and right thyroid lobes in transverse and longitudinal sections, has shown specificity ranging from 60% to 95% and sensitivity from 62% to 89%. Additionally, it was shown that the value of ACC for the method using decision trees as a classifier is equal to 84% for the analyzed data. Thresholding of average brightness of the ROI gave ACC equal to 76%.


Assuntos
Doença de Hashimoto/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Glândula Tireoide/diagnóstico por imagem , Adolescente , Adulto , Algoritmos , Estudos de Casos e Controles , Análise Discriminante , Humanos , Pessoa de Meia-Idade , Ultrassonografia , Adulto Jovem
18.
Biomed Eng Online ; 11: 48, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22898180

RESUMO

INTRODUCTION: This paper concerns the analysis of the features obtained from thyroid ultrasound images in left and right transverse and longitudinal sections. In the image analysis, the thyroid lobe is treated as a texture for healthy subjects and patients with Hashimoto's disease. The applied methods of analysis and image processing were profiled to obtain 10 features of the image. Then, their significance in the classification was shown. MATERIAL: In this study, the examined group consisted of 29 healthy subjects aged 18 to 60 and 65 patients with Hashimoto's disease. For each subject, four ultrasound images were taken. They were all in transverse and longitudinal sections of the right and left lobe of the thyroid, which gave 376 images in total. METHOD: 10 different features obtained from each ultrasound image were suggested. The analyzed thyroid lobe was marked automatically or manually with a rectangular element. RESULTS: The analysis of 10 features and the creation for each one of them their own decision tree configuration resulted in distinguishing 3 most significant features. The results of the quality of classification show accuracy above 94% for a non-trimmed decision tree.


Assuntos
Doença de Hashimoto/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Glândula Tireoide/diagnóstico por imagem , Adolescente , Adulto , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Ultrassonografia , Adulto Jovem
19.
Biomed Eng Online ; 11: 35, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-22727245

RESUMO

BACKGROUND: The available scientific literature contains descriptions of manual, semi-automated and automated methods for analysing angiographic images. The presented algorithms segment vessels calculating their tortuosity or number in a given area. We describe a statistical analysis of the inclination of the vessels in the fundus as related to their distance from the center of the optic disc. METHODS: The paper presents an automated method for analysing vessels which are found in angiographic images of the eye using a Matlab implemented algorithm. It performs filtration and convolution operations with suggested masks. The result is an image containing information on the location of vessels and their inclination angle in relation to the center of the optic disc. This is a new approach to the analysis of vessels whose usefulness has been confirmed in the diagnosis of hypertension. RESULTS: The proposed algorithm analyzed and processed the images of the eye fundus using a classifier in the form of decision trees. It enabled the proper classification of healthy patients and those with hypertension. The result is a very good separation of healthy subjects from the hypertensive ones: sensitivity - 83%, specificity - 100%, accuracy - 96%. This confirms a practical usefulness of the proposed method. CONCLUSIONS: This paper presents an algorithm for the automatic analysis of morphological parameters of the fundus vessels. Such an analysis is performed during fluorescein angiography of the eye. The presented algorithm automatically calculates the global statistical features connected with both tortuosity of vessels and their total area or their number.


Assuntos
Algoritmos , Vasos Sanguíneos , Fundo de Olho , Processamento de Imagem Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Automação , Humanos , Pessoa de Meia-Idade , Adulto Jovem
20.
Materials (Basel) ; 15(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35744221

RESUMO

The aim of the study was the qualitative assessment of new materials based on a polycarbonate matrix in terms of its use in 3D printing and its processing and geometric modification (cutting). Filaments made of the new material doped with talc in five different proportions were visually inspected with a microscope. The calibration and test models were made using the FFF (fused filament fabrication) technique. In addition, its susceptibility to the drill and the behavior of the shavings were assessed and the temperature changing during drilling was measured. The implant was inserted to measure its resonance stability in each of the holes made and translated into the value of the implant stability quotient (ISQ) ranging from 1 to 100. The results were compared to those obtained for the training model of the skull bone. The amount of filler has been shown to affect the composite. Moreover, due to the properties of talc, a compatibilizer (polyol) was used. Differences were observed between the model made of the commercial material, the model made of the dried, tested material, and the model made of the undried material. It was confirmed that the presence of water in the material during its processing is important.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA