BACKGROUND AND PURPOSE: Increased echogenicity of the substantia nigra is a typical transcranial sonography finding in Parkinson disease. Experimental software for digital analysis of the echogenic substantia nigra area has been developed. The aim of this study was to compare the evaluation of substantia nigra echogenicity by using digital analysis with a manual measurement in patients with Parkinson disease and healthy volunteers. MATERIALS AND METHODS: One hundred thirteen healthy volunteers were enrolled in the derivation cohort, and 50 healthy volunteers and 30 patients with Parkinson disease, in the validation cohort. The substantia nigra was imaged from the right and left temporal bone window by using transcranial sonography. All subjects were examined twice by using different sonographic machines by an experienced sonographer. DICOM images of the substantia nigra were encoded; then, digital analysis and manual measurement of the substantia nigra were performed. The 90th percentile of the derivation cohort values was used as a cut-point for the evaluation of the hyperechogenic substantia nigra in the validation cohort. The Spearman coefficient was used for assessment of the correlation between both measurements. The Cohen κ coefficient was used for the assessment of the correlation between both measurements and Parkinson disease diagnosis. RESULTS: The Spearman coefficient between measurements by using different machines was 0.686 for digital analysis and 0.721 for manual measurement (P < .0001). Hyperechogenic substantia nigra was detected in the same 26 (86.7%) patients with Parkinson disease by using both measurements. Cohen κ coefficients for digital analysis and manual measurement were 0.787 and 0.762, respectively (P < .0001). CONCLUSIONS: The present study showed comparable results when measuring the substantia nigra features conventionally and by using the developed software.

• MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Brain Stem ultrasonography   MeSH
• Parkinson Disease ultrasonography   MeSH
• Image Processing, Computer-Assisted * MeSH
• Aged MeSH
• Temporal Bone ultrasonography   MeSH
• Substantia Nigra ultrasonography   MeSH
• Ultrasonography, Doppler, Transcranial * MeSH
• Healthy Volunteers MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

We present a measurement of an object's in-plane velocity in one direction by the use of the speckle correlation method. Numerical correlations of speckle patterns recorded periodically during motion of the object under investigation give information used to evaluate the object's in-plane velocity. The proposed optical setup uses a detection plane in the image field and enables one to detect the object's velocity within the interval (10-150) microm x s(-1). Simulation analysis shows a way of controlling the measuring range. The presented theory, simulation analysis, and setup are verified through an experiment of measurement of the velocity profile of an object.

• MeSH
• Time Factors MeSH
• Equipment Design MeSH
• Financing, Organized MeSH
• Physics methods   MeSH
• Metals MeSH
• Lasers MeSH
• Microscopy methods   instrumentation   MeSH
• Optics and Photonics MeSH
• Image Processing, Computer-Assisted MeSH
• Motion MeSH
• Models, Statistical MeSH
• Models, Theoretical MeSH

Cíl: Včasná identifikace pacientů s vyšším rizikem vzniku nestabilního aterosklerotického plátu je základem úspěšné preventivní léčby. Cílem studie bylo najít ultrazvukové charakteristiky aterosklerotického plátu v karotickém řečišti zvyšující riziko jeho progrese. Metodika: Do analýzy byli zařazeni všichni pacienti, kteří absolvovali pravidelné sonografické kontroly během 36 měsíců. Při každé kontrole byly hodnoceny následující charakteristiky aterosklerotického plátu v karotickém řečišti: maximální šíře, echogenita, homogenita, povrch plátu a přítomnost kalcifikací. Pro statistické zpracování byly použity jednorozměrná a vícerozměrná logistická regresní analýza. Výsledky: Stabilní aterosklerotické pláty v obou karotických řečištích byly detekovány u 332 pacientů (125 mužů, průměrný věk 66,7 ± 9,7 let). Progredující aterosklerotický plát alespoň v jedné karotické tepně byl detekován u 255 pacientů (126 mužů, průměrný věk 69,5 ± 8,3 roku). Vícerozměrná logistická regresní analýza identifikovala tři rizikové faktory progrese plátu v karotidách: šíře aterosklerotického plátu (s nárůstem šíře o 1 mm narůstá riziko progrese plátu během následujících 3 let o 73,5 %; p < 0,0001), nerovný povrch plátu (zvýšení rizika progrese o 56,4 %; p = 0,007) a ulcerovaný plát (zvýšení rizika progrese o 81,9 %; p = 0,025). Závěr: Šíře, nerovný a ulcerovaný povrch aterosklerotického plátu v karotidách jsou nezávislými rizikovými faktory jeho progrese.

Aim: Early identification of patients at higher risk of unstable atherosclerotic plaque development is essential for successful preventive treatment. The aim of the study was to identify the duplex sonography carotid atherosclerotic plaque risk characteristics for plaque progression. Methods: All patients who underwent regular sonographic examinations within 36 months were included in the analysis. At each control, the following characteristics of the atherosclerotic plaque in the carotid artery were evaluated: maximum width, echogenicity, homogeneity, plaque surface and the presence of calcifications. Univariate and multivariate logistic regression analyses were used for the statistical evaluation. Results: Stable atherosclerotic plaques in both carotid arteries were detected in 332 patients (125 males, mean age 66.7 ± 9.7 years). Progressive atherosclerotic plaque in at least one carotid artery was detected in 255 patients (126 males, mean age 69.5 ± 8.3 years). Multivariate logistic regression analysis identified 3 risk factors for carotid atherosclerotic plaque progression: plaque width (increasing the risk of plaque progression within 3 years by 73.5% per 1 mm; P < 0.0001), irregular plaque surface (increasing the risk of progression by 56.4%; P = 0.007) and exulcerated plaque (increasing the risk of progression by 81.9%; P = 0.025). Conclusion: The width and irregular and exulcerated surface of the carotid atherosclerotic plaque are independent risk factors for plaque progression.

• MeSH
• Plaque, Atherosclerotic * diagnostic imaging   MeSH
• Atherosclerosis diagnostic imaging   MeSH
• Clinical Studies as Topic MeSH
• Humans MeSH
• Disease Progression MeSH
• Risk Factors MeSH
• Ultrasonography methods   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Research Support, Non-U.S. Gov't MeSH

• MeSH
• Image Interpretation, Computer-Assisted MeSH

• Conspectus
• Lékařské vědy. Lékařství
• NML Fields
• lékařská informatika

Tento článek se zabývá automatickou lokalizací objektů (očí, úst) ve dvourozměrných (2D) černobílých obrazech obličejů. Je motivován praktickým problémem v genetice člověka a výstup lokalizace objektů v dané databázi obrazů je zapotřebí pro řešení dalších úloh v genetickém výzkumu. V článku se aplikuje robustní filtr na obrazy s cílem odstranit šum. Hlavní metodou jsou šablony. Ústa a obě oči se lokalizují současně za použití váženého Pearsonova korelačního koeficientu nebo jeho robustní analogie založené na robustních regresních metodách. V databázi s 212 obrazy obličejů tato metoda správně nalezne ústa a oči ve 100 % případů. Také robustní korelační koeficient založený na regresní metodě nejmenších vážených čtverců lokalizuje ústa a oči ve 100 % obrazů uvažované databáze. Článek studuje robustní aspekty této metody vzhledem k otočení, šumu, okluzi a asymetrii v obraze. Současná lokalizace úst i obou očí je invariantní vůči libovolnému otočení obličeje. Tato studie využívá speciální vlastnosti daných obrazů obličejů vzhledem k očekávanému použití v genetických aplikacích.

This paper is devoted to automatic localization of objects (eyes, mouth) in two-dimensional (2D) grey scale images of faces. Motivated by a practical problem in human genetics, the output of the localization of objects in the given database of images is needed for further tasks in the genetic research. A robust filter is applied on the image to ensure denoising. Templates are used as the main method. The mouth and both eyes are localized jointly using the weighted Pearson product-moment correlation coefficient or its robust analogy based on robust regression methods. In the database with 212 images of faces the method allows to locate the mouth and eyes correctly in 100 % of cases. Also the robust correlation coefficient based on the least weighted squares regression localizes the mouth and both eyes in 100 % of images of the given database. Robustness aspects of the method are examined with respect to rotation, noise, occlusion and asymmetry in the image. The joint localization of the mouth and both eyes produces the method invariant to rotation of any degree. This work is tailor made for the given images with expected usage of the methods in genetic applications.

• Keywords
• lokalizace objektů, šablony, detekce oči a úst, robustní korelační analýza, redukce šumu,
• MeSH
• Biometry methods   MeSH
• Contrast Sensitivity physiology   MeSH
• Databases as Topic standards   MeSH
• Photography methods   MeSH
• Genetic Research MeSH
• Image Interpretation, Computer-Assisted methods   MeSH
• Humans MeSH
• Face MeSH
• Eye MeSH
• Image Processing, Computer-Assisted methods   MeSH
• Regression Analysis MeSH
• Reproducibility of Results MeSH
• Pattern Recognition, Physiological physiology   MeSH
• Subtraction Technique standards   MeSH
• Mouth MeSH
• Image Enhancement methods   MeSH
• Check Tag
• Humans MeSH

In this work, we propose a new approach for three-dimensional registration of MR fractional anisotropy images with T1-weighted anatomy images of human brain. From the clinical point of view, this accurate coregistration allows precise detection of nerve fibers that is essential in neuroscience. A template matching algorithm combined with normalized cross-correlation was used for this registration task. To show the suitability of the proposed method, it was compared with the normalized mutual information-based B-spline registration provided by the Elastix software library, considered a reference method. We also propose a general framework for the evaluation of robustness and reliability of both registration methods. Both registration methods were tested by four evaluation criteria on a dataset consisting of 74 healthy subjects. The template matching algorithm has shown more reliable results than the reference method in registration of the MR fractional anisotropy and T1 anatomy image data. Significant differences were observed in the regions splenium of corpus callosum and genu of corpus callosum, considered very important areas of brain connectivity. We demonstrate that, in this registration task, the currently used mutual information-based parametric registration can be replaced by more accurate local template matching utilizing the normalized cross-correlation similarity measure.

• MeSH
• Algorithms MeSH
• Anisotropy MeSH
• Image Interpretation, Computer-Assisted methods   MeSH
• Humans MeSH
• Longitudinal Studies MeSH
• Magnetic Resonance Imaging methods   MeSH
• Brain Mapping methods   MeSH
• Brain anatomy & histology   MeSH
• Image Processing, Computer-Assisted methods   MeSH
• Reference Values MeSH
• Reproducibility of Results MeSH
• Aged MeSH
• Software MeSH
• Imaging, Three-Dimensional methods   MeSH
• Check Tag
• Humans MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

A number of fluorescence microscopy techniques are described to study dynamics of fluorescently labeled proteins, lipids, nucleic acids, and whole organelles. However, for studies of plant plasma membrane (PM) proteins, the number of these techniques is still limited because of the high complexity of processes that determine the dynamics of PM proteins and the existence of cell wall. Here, we report on the usage of raster image correlation spectroscopy (RICS) for studies of integral PM proteins in suspension-cultured tobacco cells and show its potential in comparison with the more widely used fluorescence recovery after photobleaching method. For RICS, a set of microscopy images is obtained by single-photon confocal laser scanning microscopy (CLSM). Fluorescence fluctuations are subsequently correlated between individual pixels and the information on protein mobility are extracted using a model that considers processes generating the fluctuations such as diffusion and chemical binding reactions. As we show here using an example of two integral PM transporters of the plant hormone auxin, RICS uncovered their distinct short-distance lateral mobility within the PM that is dependent on cytoskeleton and sterol composition of the PM. RICS, which is routinely accessible on modern CLSM instruments, thus represents a valuable approach for studies of dynamics of PM proteins in plants.

• MeSH
• Cell Membrane chemistry   MeSH
• Microscopy, Confocal methods   MeSH
• Membrane Proteins analysis   MeSH
• Image Processing, Computer-Assisted methods   MeSH
• Plant Cells chemistry   MeSH
• Spectrum Analysis methods   MeSH
• Nicotiana chemistry   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

INTRODUCTION: The aim of this study was to determine the reproducibility and accuracy of linear measurements on 2 types of dental models derived from cone-beam computed tomography (CBCT) scans: CBCT images, and Anatomodels (InVivoDental, San Jose, Calif); these were compared with digital models generated from dental impressions (Digimodels; Orthoproof, Nieuwegein, The Netherlands). The Digimodels were used as the reference standard. METHODS: The 3 types of digital models were made from 10 subjects. Four examiners repeated 37 linear tooth and arch measurements 10 times. Paired t tests and the intraclass correlation coefficient were performed to determine the reproducibility and accuracy of the measurements. RESULTS: The CBCT images showed significantly smaller intraclass correlation coefficient values and larger duplicate measurement errors compared with the corresponding values for Digimodels and Anatomodels. The average difference between measurements on CBCT images and Digimodels ranged from -0.4 to 1.65 mm, with limits of agreement values up to 1.3 mm for crown-width measurements. The average difference between Anatomodels and Digimodels ranged from -0.42 to 0.84 mm with limits of agreement values up to 1.65 mm. CONCLUSIONS: Statistically significant differences between measurements on Digimodels and Anatomodels, and between Digimodels and CBCT images, were found. Although the mean differences might be clinically acceptable, the random errors were relatively large compared with corresponding measurements reported in the literature for both Anatomodels and CBCT images, and might be clinically important. Therefore, with the CBCT settings used in this study, measurements made directly on CBCT images and Anatomodels are not as accurate as measurements on Digimodels.

• MeSH
• Cephalometry statistics & numerical data   MeSH
• Humans MeSH
• Cone-Beam Computed Tomography statistics & numerical data   MeSH
• Image Processing, Computer-Assisted statistics & numerical data   MeSH
• Surface Properties MeSH
• Reproducibility of Results MeSH
• Software MeSH
• Imaging, Three-Dimensional statistics & numerical data   MeSH
• Tooth Crown anatomy & histology   MeSH
• Models, Dental * MeSH
• Dental Arch anatomy & histology   MeSH
• Dental Impression Technique statistics & numerical data   MeSH
• Tooth anatomy & histology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH

Background: We tested whether the level of endothelial dysfunction assessed by digital tonometry, and expressed as reactive hyperemia index (RHI), is related to occurrences of a discrepancy between fractional flow reserve (FFR) and the instantaneous wave free ratio (iFR) (ClinicalTrials.gov identifier: NCT03033810).Methods: We examined patients with coronary stenosis in the range of 40-70%, assessed by both FFR and iFR (system Philips-Volcano) for stable angina. We included consecutive patients with FFR and iFR in one native coronary artery, and who had had no previous intervention.Results: We included 138 patients. Out of those, 24 patients (17.4%) had a negative FFR (with an FFR value >0.8) and positive iFR (with a iFR value ≤0.89) - designated the FFRn/iFRp discrepancy group, and 22 patients (15.9%) had a positive FFR (≤0.8) and negative iFR (>0.89) - designated the FFRp/iFRn discrepancy. RHI was higher in the discrepancy groups compared the group without discrepancy (1.73 ± 0.79 vs. 1.48 ± 0.50, p = 0.025). However, this finding was not confirmed in multivariant logistic regression analyses. Patients with any type of discrepancy differed from the agreement group by having a higher occurrence of diabetes mellitus [9 patients (21.4%) vs. 36 patients (39.6%), p = 0.029], active smoking (23 patients or 54.8% vs. 26 patients or 28.6%, p = 0.003) and lower use of calcium channel blockers (9 patients, 21.4%, vs. 43 patients, 46.7%, p = 0.004).Conclusion: The presence of endothelial dysfunction can be associated with a discrepancy in FFR/iFR. However, RHI correlated with risk factors of atherosclerosis, not with FFR or iFR.

• MeSH
• Endothelium, Vascular physiopathology   MeSH
• Vascular Resistance MeSH
• Fractional Flow Reserve, Myocardial * MeSH
• Coronary Stenosis * diagnosis   physiopathology   MeSH
• Laser-Doppler Flowmetry * instrumentation   methods   MeSH
• Humans MeSH
• Manometry instrumentation   methods   MeSH
• Microcirculation physiology   MeSH
• Software Design * MeSH
• Image Processing, Computer-Assisted MeSH
• Aged MeSH
• Software MeSH
• Myocardial Perfusion Imaging methods   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Observational Study MeSH

This paper presents a new method for the determination of the volume, surface area and depth of skin defects. The method is based on the description of a spatial defect using a pyramid (made, for example, from injection needles), which is placed over the defect. The projection of the pyramid on to the defect is photographed using a digital camera and subsequently compared with the projection of the same pyramid on to a sheet of grid paper. The defect is mathematically reconstructed on a computer, and an optimal body shape describing the defect is found, using a number of simplifications and assumptions. The method was then validated using a plaster mold of a real foot with 19 defects simulating real wounds. These plaster wounds were molded using alginate hydrocolloid, and the volume, surface area and depth were measured and compared with the results of the pyramid projection by means of regression analysis.This method correlates in all variables with correlation coefficients higher than 0.9. It can be concluded that the projection pyramid method correlates well with the reference mold method and can be used with good results for a whole range of variables.

• MeSH
• Photography methods   MeSH
• Skin pathology   MeSH
• Humans MeSH
• Signal Processing, Computer-Assisted * MeSH
• Wounds and Injuries pathology   MeSH
• Reproducibility of Results MeSH
• Software MeSH
• Foot Ulcer pathology   MeSH
• Imaging, Three-Dimensional * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Validation Study MeSH