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PubMed1995

Image analysis and image processing as tools to measure initial rates of enzyme reactions in sections: distribution patterns of glutamate dehydrogenase activity in rat liver lobules.

To analyze regional differences in the activity of glutamate dehydrogenase in rat liver in situ, we developed an image recording and processing system for monitoring the formation of a colored final reaction product in time. All absorbance measurements of test and control reactions in time in consecutive sections were used to fit the data to a quadratic curve, with the derivative at t = 0 representing the initial velocity of formazan formation. The images of sections incubated for test and control reactions were topographically matched with an affine transformation using the positions of vessels as fiducials. Specific enzyme activity was calculated by subtracting the coefficients representing the initial velocity at corresponding locations in the test and control reactions and appeared to be 8 and 4 mumoles glutamate converted per min per cm3 of tissue at 20 degrees C in pericentral and periportal zones of fasted female rats, respectively. Those values are in agreement with biochemical data. The ability to construct two-dimensional images of cellular distribution patterns of enzyme activity in liver lobules is particularly useful for the study of metabolic zonation in this organ.

Animals↗
PubMed2006

Analysis of functional image analysis contest (FIAC) data with brainvoyager QX: From single-subject to cortically aligned group general linear model analysis and self-organizing group independent component analysis.

The Functional Image Analysis Contest (FIAC) 2005 dataset was analyzed using BrainVoyager QX. First, we performed a standard analysis of the functional and anatomical data that includes preprocessing, spatial normalization into Talairach space, hypothesis-driven statistics (one- and two-factorial, single-subject and group-level random effects, General Linear Model [GLM]) of the block- and event-related paradigms. Strong sentence and weak speaker group-level effects were detected in temporal and frontal regions. Following this standard analysis, we performed single-subject and group-level (Talairach-based) Independent Component Analysis (ICA) that highlights the presence of functionally connected clusters in temporal and frontal regions for sentence processing, besides revealing other networks related to auditory stimulation or to the default state of the brain. Finally, we applied a high-resolution cortical alignment method to improve the spatial correspondence across brains and re-run the random effects group GLM as well as the group-level ICA in this space. Using spatially and temporally unsmoothed data, this cortex-based analysis revealed comparable results but with a set of spatially more confined group clusters and more differential group region of interest time courses.

Algorithms↗
PubMed1997

Computer image analysis of ultrasound images for discriminating and grading liver parenchyma disease employing a hierarchical decision tree scheme and the multilayer perceptron neural network classifier.

Differential diagnosis of liver parenchyma disease and grading of the hepatic disease on ultrasound is a common radiological problem that influences patient management. The aim of this study was to apply image analysis methods on ultrasound images for discriminating liver cirrhosis from fatty liver infiltration and for grading hepatic disease, which is important in the management of the patients. Ultrasound images of histologically confirmed 18 livers with cirrhosis, 37 livers with fatty infiltration, and 24 normal livers of healthy volunteers were selected and were digitized for further computer processing. Twenty two textural features were calculated from small matrix samples selected from the ultrasound image matrix of the liver parenchyma. These features were used in the design a three level hierarchical decision tree classification scheme, employing the multilayer perceptron neural network classifier at each hierarchical tree level. At the first tree level, classification accuracy for distinguishing normal from abnormal livers was 93.7%, at the second level the accuracy for discriminating cirrhosis from fatty infiltration was 90.9%, and at the third level the accuracy in distinguishing between low and high grading liver cirrhosis or fatty infiltration was 94.1% and 84.9% respectively. The proposed computer software system may be of value to the radiologists in assessing liver parenchyma disease.

Decision Trees↗
PubMed1991

Trabecular bone densitometry using interactive image analysis.

Interactive image analysis is a novel application of digital image processing to the densitometry of trabecular bone. Briefly, the exposed surfaces of bleached slices of bone are illuminated so that the trabecular tips are bright in relation to the interstices. The image is then captured by a TV camera and digitized with an interactive image analysis system. A grey scale is then chosen that differentiates the bone at the surface from the background. Finally, a computer program calculates the area fraction of bone within a user-specified box which, by Delesse's principle, is an estimate of the volume fraction of bone. The reproducibility of the technique (expressed as an average SD) is +/- 1.5 vol. % and has surface-discriminating capabilities comparable to the traditional point-counting method but is faster and more precise. Most importantly, the technique permits biomechanical testing of the sample after its density has been determined.

Aged↗
PubMed1990

Study of fibronectin expression in tumour cells by dot-blot and in situ hybridization: quantitative evaluation by image analysis.

An Image Analysis program was used for the quantitative evaluation and comparison of the fibronectin (FN) mRNA detected by dot-blot and in situ hybridization in different cell lines. These techniques were applied for the evaluation of FN mRNA synthesized by human normal fibroblasts (Flow 7000) and by four tumour-derived cell lines (HeLa, epithelioid carcinoma; 8387, fibrosarcoma; RD, rhabdomyosarcoma; SK Hep-1, hepatocarcinoma). Dot-blot analysis showed that the cell types analysed synthesize different levels of FN mRNA. Flow 7000 are the highest producers while HeLa the lowest. In situ hybridization confirmed these results and furthermore showed that while Flow 7000, 8387 and HeLa cells synthesized homogeneous levels of FN mRNA, RD and SK Hep-1 could be subdivided into two populations expressing high or low levels of FN mRNA. The combined analysis of dot-blot, in situ hybridization and Image Analysis allowed the quantitation of the number of FN mRNA molecules expressed by single cells. This approach is therefore an invaluable tool when evaluating mRNA expression in heterogeneous cell populations like tumour-derived cell lines, during cell cycle or in histological tissue sections.

Cell Line↗
PubMed1995

Comparison of ploidy analysis by flow cytometry and image analysis in hydatidiform mole and non-molar abortion.

Determination of DNA ploidy is useful in the diagnosis and classification of hydatidiform mole. Most reports of ploidy analysis in molar tissue have used DNA flow cytometry. Although image analysis cytometry offers theoretical advantages over flow cytometry, there have been few reports of ploidy analysis by image analysis in hydatidiform mole. We selected 47 cases and measured DNA ploidy by flow cytometry and image analysis cytometry in complete hydatidiform mole, partial hydatidiform mole and non-molar abortion. The two cytometry modalities were compared using kappa statistics. There was reasonable overall agreement between the two modalities (kappa = 0.69) and when ploidy was stratified into diploid/polyploid and triploid categories there was near perfect agreement (kappa = 0.93). Aneuploid cell populations, which were not evident on flow cytometry, were identified by image analysis in a significant proportion of complete and partial hydatidiform moles and in a small number of non-molar abortions. Flow cytometry and image analysis cytometry yield comparable ploidy information, useful in the diagnosis and classification of hydatidiform mole. Image analysis cytometry offers greater sensitivity in the detection of small non-diploid cell populations but the significance of this latter finding is uncertain.

Abortion, Spontaneous↗
PubMed1993

A method for the enumeration of bacterial adhesion to epithelial cells using image analysis.

Computerised image analysis was utilised to enumerate the attachment of Staphylococcus epidermidis to HEp2 cell monolayers. A differential staining technique was employed such that individual staphylococcal cells stood out in sharp contrast against the uneven cell surface and granular contents of the epithelial cells. The primary image analysis operation involved subtracting an out-of-focus image from an in-focus image of the bacteria on the monolayer, thereby accentuating the bacterial image. Enumeration, using a particle counting routine, was rapid and reproducible, facilitating counting in excess of 700 bacteria per field at x 500 magnification. The computerised programme compared favourably with manual counting and would provide a rapid, objective and morphologically discriminatory method for evaluating bacterial attachment to various tissues.

Bacterial Adhesion↗
PubMed2001

Quantification of autolysis in Penicillium chrysogenum by semiautomated image analysis.

An image analysis method is described for the characterization of empty (autolyzed and inactive) regions within the mycelia of filamentous fungi. It extends a previous method that characterized only regions filled with cytoplasm or vacuoles (i.e., the active biomass). The method is semiautomatic, requiring some manual editing before automated measurements. When the method was used for samples from a batch fermentation of an industrial strain of Penicillium chrysogenum, the empty regions were observed to constitute up to 15% (by projected area) of the biomass during the growth phase. After nutrient exhaustion, however, the proportion of empty regions rose rapidly, eventually representing more than 50% of the biomass by the end of fermentation. The increase in the percentage of empty regions coincided with a decrease in biomass (as measured by dry cell weight) and a fall in penicillin titre. Further morphological analysis revealed that fragmentation of mycelia, particularly clumps, coincided with increases in the levels of empty regions. This new image analysis method gave additional information on hyphal differentiation and a measure of autolysis. It was also a useful indicator of the processes leading to autolysis.

Biomass↗
PubMedDate not supplied

Spore dimensions of Puccinia species of cereal hosts as determined by image analysis.

Digital image analysis was used to measure dimensions of spores produced by Puccinia coronata, P. graminis, P. hordei, P. recondita, P. striiformis and P. triticina. Included were teliospores, basidiospores, urediniospores and, except for P. striiformis, pycniospores and aeciospores. Length, width and projection area of spores were measured with NIH Image or Scion software. By using limits on size, spores were automatically selected and measured, except for teliospores, which required manual elimination of the pedicel and separation of images of adhering spores. Length and width were determined as the major and minor axes of the best fitting ellipse for each spore. This procedure gave values for length and width close to results obtained with an ocular micrometer. Projection area was determined as the number of pixels within spore boundaries multiplied by the area represented by each pixel, giving values that are not feasible to obtain accurately with an ocular micrometer. Of the species studied, spores of P. recondita had the largest dimensions, P. triticina had the smallest. The rank of the six species based on increasing width, length or projection area was almost the same, using each spore type except pycniospores. Generally, differences of 5% in a given spore dimension between two species were significant. Differences between species were greater with basidiospores and aeciospores than with other spore types. Teliospores were unique in that length and width were negatively correlated, resulting in less variation in area than in length or width. The results indicate that image analysis is useful for measuring spore dimensions, that projection area of spores is a useful added parameter for characterizing rust species and that dimensions of teliospores, basidiospores, aeciospores and urediniospores each are potentially useful for differentiating species.

Basidiomycota↗
PubMed1999

Identification of synergistic interactions among microorganisms in biofilms by digital image analysis.

Digital image analysis showed that reductions in biofilm plating efficiency were due to the loss of protection provided by two benzoate-degrading strains of Pseudomonas fluorescens. This loss in protection was due to the spatial separation of the protective organisms from benzoate-sensitive organisms during the dilution process. Communities were cultivated in flow cells irrigated with trypticase soy broth. When the effluent from these flow cells was plated on 0.15% benzoic acid, satellite colonies formed only in the vicinity of primary colonies. A digital image analysis procedure was developed to measure the size and spatial distribution of these satellites as a function of distance from the primary colony. The size of satellites served as a measure of growth, and the number per unit area served as a measure of survival. At the three dilutions tested, the size and concentration of satellite colonies varied inversely with distance from the primary colonies. When these measurements were plotted, the slopes were used to quantify the effect of bacterial association on the growth and survivability of the satellites. In the absence of the primary colonies, satellites grew in axenic culture only at low benzoate concentrations. Thus benzoate-degrading organisms are capable of creating a protective microenvironment for other members of biofilm communities.

Agar↗
PubMed1997

[Comparison of film-screen combinations with contrast detail diagram and interactive image analysis. 2: Linear assessment of grey scale ranges with interactive image analysis].

The following three screen-film combinations were compared: a) a combination of anticrossover film and UV-light emitting screens, b) a combination of blue-light emitting screens and film, and c) a conventional green fluorescing screen-film combination. Radiographs of a specially designed plexiglass phantom (0.2 x 0.2 x 0.12 m3) with bar patterns of lead and plaster and of air, respectively were obtained using the following parameters: 12 pulse generator, 0.6 mm focus size, 4.7 mm aluminum pre-filter, a grid with 40 lines/cm (12:1) and a focus-detector distance of 1.15 m. Image analysis was performed using an IBAS system and a Zeiss Kontron computer. Display conditions were the following: display distance 0.12 m, a vario film objective 35/70 (Zeiss), a video camera tube with a PbO photocathode, 625 lines (Siemens Heimann), an IBAS image matrix of 512 x 512 pixels with a resolution of 7 lines/mm, the projected matrix area was 5000 microns2. Grey scale ranges were measured on a line perpendicular to the grouped bar patterns. The difference between the maximum and minimum density value served as signal. The spatial resolution of the detector system was measured when the signal value was three times higher than the standard deviation of the means of multiple density measurements. The results showed considerable advantages of the two new screen-film combinations as compared to the conventional screen-film combination. The result was contradictory to the findings with pure visual assessment of thresholds (part I) that had found no differences. The authors concluded that (automatic) interactive image analysis algorithms serve as an objective measure and are specifically advantageous when small differences in image quality are to be evaluated.

Algorithms↗
PubMed2005

Software for quantification of labeled bacteria from digital microscope images by automated image analysis.

Automated image analysis software, CellC, was developed and validated for quantification of bacterial cells from digital microscope images. CellC enables automated enumeration of bacterial cells, comparison of total count and specific count images [e.g., 4',6-diamino-2-phenylindole (DAPI) and fluorescence in situ hybridization (FISH) images], and provides quantitative estimates of cell morphology. The software includes an intuitive graphical user interface that enables easy usage as well as sequential analysis of multiple images without user intervention. Validation of enumeration reveals correlation to be better than 0.98 when total bacterial counts by CellC are compared with manual enumeration, with all validated image types. The software is freely available and modifiable: the executable files and MATLAB source codes can be obtained at www. cs. tut.fi/sgn/csb/cellc.

Bioreactors↗
PubMed2004

A new technique for endobronchial ultrasonography and comparison of two ultrasonic probes: analysis with a plot profile of the image analysis software NIH Image.

STUDY OBJECTIVES: Endobronchial ultrasonography (EBUS) is currently the sole clinical method available for delineating the bronchial wall structure; however, the image resolution is inadequate. Thus, an improved image analysis system is needed for both a more accurate and more readily interpretable endobronchial ultrasonogram. MATERIALS AND METHODS: A total of 10 patients underwent pulmonary resection for lung cancer. EBUS was performed on the bronchi of the resected lungs, which had been immersed in physiologic saline solution. The same bronchial lesion in each specimen was imaged with two probes: 20 MHz and 30 MHz. The images were analyzed using the plot profile derived from freeware image analysis software: NIH Image (National Institutes of Health; Bethesda, MD). The measured echo intensity of the bronchial wall was statistically analyzed. RESULTS: A normal bronchial wall image consists of five layers, and the plot profile shows a W-shaped curve. The mean value of the echo intensity of each peak or trough of the W-shaped curve was calculated and compared for both probes. The differences in the mean echo intensity between both the third and fourth layer and the second and fourth layer were found to be significantly greater with the 30-MHz probe than with the 20-MHz probe. The echo intensity curve of a central-type lung cancer was not W shaped, indicating that the bronchial wall was not composed of the normal five layers. CONCLUSION: We employed image analysis software and drew a plot to obtain a W-shaped curve from the EBUS image data. This enabled us to make an objective assessment of the laminar structure of the bronchial wall. In order to clearly recognize the laminar structure of the bronchial wall, the 30-MHz probe was found to be more useful than the 20-MHz probe.

Bronchi↗
PubMed1993

Image analysis in immunohistochemistry. Factors with a possible influence on the performance of VIDAS version 2.0, a commercially available true color image analysis system.

This paper describes the evaluation of several factors with a possible influence on the performance of a commercially available image analysis system capable of true color image analysis. The software used by this system is VIDAS Version 2.0. The following factors were evaluated: illumination, power supply, warming up, shading correction, averaging of image intake, hue luminance and saturation images and relation of illumination to quantification of area percentage (area %) of positively staining structures. The first six factors were evaluated by using a macro, with which it is possible to obtain information on variations over the image and over time. The last factor was evaluated by repeated measurement of area % of positive staining in a routinely processed tissue section. In our setting, stability of illumination and warmup time of the camera appeared to be the most important factors with influence on the performance of the image analysis system.

Color↗
PubMed2001

Image analysis of quick phase eye movements in nystagmus with high-speed video system.

There are several methods of measuring horizontal, vertical and torsional nystagmus for the diagnosis of vertigo. Using Frentzel glasses, electronystagmography (ENG) and video-oculography (VOG) are common methods for observing nystagmus. In this study, a high-speed video camera is used to analyse high-speed eye movements, including three components of nystagmus, in order to monitor precisely the amplitude and velocity of the quick phase of nystagmus. To confirm the accuracy of the analysis, images of optokinetic nystagmus (OKN) evoked by a stimulating device were analysed. We obtained a high linearity with regard to the relation between the horizontal nystagmus amplitude detected with the high-speed video system and ENG (R2= 0.99). On comparison of the maximum velocities detected with 30Hz and with 250 Hz at each amplitude, the velocities calculated at 30Hz were smaller than those calculated at 250 Hz. At an amplitude of 5 degrees , the 30 Hz velocity decreased by 50%, while a decrease of 35% was observed at 15 degrees. The vertical nystagmus data obtained using high-speed VOG was different in appearance to that obtained using ENG. The torsional component of nystagmus was also measured, and was recorded in the form of a large number of sampling points.

Electronystagmography↗
PubMed1988

Cancer detection by quantitative fluorescence image analysis.

Quantitative fluorescence image analysis is a rapidly evolving biophysical cytochemical technology with the potential for multiple clinical and basic research applications. We report the application of this technique for bladder cancer detection and discuss its potential usefulness as an adjunct to methods used currently by urologists for the diagnosis and management of bladder cancer. Quantitative fluorescence image analysis is a cytological method that incorporates 2 diagnostic techniques, quantitation of nuclear deoxyribonucleic acid and morphometric analysis, in a single semiautomated system to facilitate the identification of rare events, that is individual cancer cells. When compared to routine cytopathology for detection of bladder cancer in symptomatic patients, quantitative fluorescence image analysis demonstrated greater sensitivity (76 versus 33 per cent) for the detection of low grade transitional cell carcinoma. The specificity of quantitative fluorescence image analysis in a small control group was 94 per cent and with the manual method for quantitation of absolute nuclear fluorescence intensity in the screening of high risk asymptomatic subjects the specificity was 96.7 per cent. The more familiar flow cytometry is another fluorescence technique for measurement of nuclear deoxyribonucleic acid. However, rather than identifying individual cancer cells, flow cytometry identifies cellular pattern distributions, that is the ratio of normal to abnormal cells. Numerous studies by others have shown that flow cytometry is a sensitive method to monitor patients with diagnosed urological disease. Based upon results in separate quantitative fluorescence image analysis and flow cytometry studies, it appears that these 2 fluorescence techniques may be complementary tools for urological screening, diagnosis and management, and that they also may be useful separately or in combination to elucidate the oncogenic process, determine the biological potential of tumors and monitor the results of chemopreventive, immunological and chemotherapeutic regimens. To our knowledge there has been no study in which quantitative fluorescence image analysis and flow cytometry were compared directly to assess the relative strengths and weaknesses for urinary tract cytology. Such a study could provide important information for urologists.

Cytodiagnosis↗
PubMed1997

Image analysis of low magnification images of fine needle aspirates of the breast produces useful discrimination between benign and malignant cases.

Fine needle aspirates of the breast (FNAB) (n = 362; 204 malignant, 158 benign), prepared by cytocentrifuge methods and stained by the Papanicolaou technique, were analysed using a semi-automated image analysis system at a low magnification which precluded resolution of nuclear detail. The measured parameters were integrated optical density, fractal textural dimension, number of cellular objects (single cells and contiguous groups of cells), distance between cellular objects (mean, s.d., skewness and kurtosis), area of cellular objects (mean, s.d., skewness, kurtosis) and the nearest neighbour statistic. The cases were divided into a 200-case training set and a 162-case test set. Analysis was performed by logistic regression and the multi-layer Perceptron type of artificial neural network. Logistic regression and the neural network produced similar performances with a sensitivity of 82-83%, specificity 85% and a positive predictive value for a malignant result of 85%. A non-parametric analysis of all the predictor variables showed that all except the mean area of cellular objects and the s.d. of this measurement were significant discriminants (P < 0.05), but most were highly interrelated and this was reflected in the selection of only three predictor variables by forward and backward conditional logistic regression. This study shows that much diagnostic information is present in low power views of FNAB, and that image analysis could form the basis of a semi-automated decision-support aid.

Biopsy, Needle↗
PubMed1998

Rapid and convenient method of autoradiography for DNA cloning using digital imaging analysis.

Digital image analysis has been used for various biochemical and molecular biological analyses instead of autoradiography with X-ray film. However, in such cases the data manipulated by an imaging analyzer was generally printed out on normal printing paper. With normal paper, it is difficult to align the signal or its position relative to the original sample. Here in, we demonstrate it to be convenient and accurate to align signal obtained by imaging analyzer with OHP film.

Autoradiography↗