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PubMed1991

An image analysis on MR imaging of the brain for hepatic encephalopathy.

Through the Magnetic Resonance Imaging (MRI) sequences with T1 weighting (TR 600 msec/TE 20 msec) of the brain, the high intensity lesions due to hepatic encephalopathy have been demonstrated markedly. The data have been collected were based upon eleven patients with clinically proven hepatic encephalopathy. Three sets of normal brain MRI which were identified with no evidence of brain or liver diseases were also included in this study. After the brain MRI slices have been identified, it showed that the affected regions of interest (ROI) were around the largest third ventricle. The histogram which was generated out of that particular slice is composed of two distinguished peaks lumped together. After the decomposition and curve fitting procedures, the Gaussian distributions were identified with the mean value and the standard deviation. One was assumed to be gray index region for gray and white matter, the other with higher gray index value was the contribution of hepatic encephalopathy. Once the range of the distribution has been determined, the affected portion can be marked and highlighted. This mechanism of histogram decomposition and curve fitting techniques shows the valuable correlation with the clinical status of MR findings.

Brain↗
PubMed1991

Mast cell fixation and staining in image analysis.

Modern image analysers automatically perform densitometric measurements and elaborate digital images. Elaboration however is subject to operator interpretation and often eliminates precious information from the areas of interest. For this reason, it was appropriate to find a staining method which would overcome this drawback and, in the case of mast cell histochemistry, limit staining to granule content. The following current staining techniques were tested: Toluidine Blue in buffered solution (solut. a) and in 0.003% alcoholic solution (solut. b) and alcoholic Astra Blue, pH 0.2 Densitometric analysis was performed on both 5 microns and semithin sections of mouse tongue fixed in Isotonic formaldehyde-acetic acid (IFAA). Digital images were obtained using 630 nm and 546 nm wavelengths for Toluidine Blue and 610 nm for Astra Blue. Direct comparison between the two Toluidine Blue solutions revealed that more pixels were captured by the 5 microns sections stained with solut. a, whilst the opposite occurred in semithin sections. Both dyes introduced a certain amount of error due to the orthochromatic component of the nucleus and cytoplasmic basophily, which had to be eliminated through image elaboration. Because of its subjective nature, this operation may in turn lead to further errors. The choice of Astra Blue as an alternative to Toluidine Blue in densitometric analysis of mastocytes is based on its property to restrict staining to the granules of mast cells. A comparison between Astra Blue and the two Toluidine Blue solutions showed that, at all transmission levels, preparations stained with Astra Blue captured more pixels than those stained with Toluidine Blue. Consequently our results suggest that the most suitable technique for densitometric image analysis is fixation of mast cells in IFAA followed with Astra Blue.

Animals↗
PubMed1989

The PARTICLE expert system for tumor grading by automated image analysis.

While automated microscopic image analysis of histologic sections has been helpful in objectivizing histologic tumor grading and investigating the relationships between grading and prognosis, expert systems have the potential of linking image analysis and other data for statistical analysis and application to a wider range of tumors. One such expert system is PARTICLE, whose development was based on many years of experience in resolving histologic problems by image analysis. This paper discusses the philosophy of expert system for tumor grading and describes its implementation in the PARTICLE system. The system's structure, operations and applications are briefly presented. PARTICLE is essentially based on the evaluation of karyometric data.

Cell Nucleus↗
PubMed1992

Quantitative DNA analysis and proliferation in breast carcinomas. A comparison between image analysis and flow cytometry.

The DNA content and proliferation in 100 invasive breast carcinomas were evaluated by computerized image analysis (IA) and flow cytometry (FCM). For DNA content, image analysis of Feulgen-stained slides of fresh tumor imprints were compared with flow cytometry of propidium iodide-stained disaggregated fresh tumor tissue. The DNA indices obtained by the two methods showed close correlation by linear regression analysis (r = 0.89, p less than .001). There were 44 (44%) diploid and 56 (56%) aneuploid tumors. There was agreement between the two methods in detection of aneuploidy in 81% of tumors. Image analysis required smaller tissue samples, permitted direct visualization and selection of tumor cells, and was more sensitive in detecting tetraploid and highly aneuploid cell populations. In contrast, flow cytometry histograms provided better resolution, and were more effective in detecting multiploid tumors and near-diploid aneuploid tumors. Aneuploidy was significantly related to various adverse prognostic parameters, namely, negative estrogen receptor, high mitotic rate, high histologic and nuclear grades. Proliferation was evaluated by measuring the FCM S phase fraction (SPF), and by image analysis quantitation of immunohistochemical staining using Ki-67 monoclonal antibody. SPF and Ki-67 count showed modest correlation (r = 0.42). Both SPF and Ki-67 count were significantly related to the mitotic rate, histologic and nuclear grades. Our results indicate that the two methods provide comparable results, but offer individual advantages and are complementary techniques in analyzing DNA ploidy and proliferation in breast carcinomas.

Adenocarcinoma, Mucinous↗
PubMed1990

Quantitative energy-filtered image analysis in cytochemistry. II. Morphometric analysis of element-distribution images.

A combination of energy-filtered electron microscopy (EFEM) and an image-analysis system (IBAS/2000) is used for a morphometric analysis of chemical reaction products in cells. Electron energy-loss spectroscopic element-distribution images are acquired from cytochemical reaction products in a variety of cellular objects: (1) colloidal thorium particles in extra-cellular coat material, (2) iron-containing ferritin particles in liver parenchymal cells, (3) barium-containing reaction products in endoplasmic reticulum stacks, (4) elements present in lysosomal cerium- and barium-containing precipitates connected with acid phosphatase (AcPase) or aryl sulphatase (AS) enzyme activity. Areas or area fractions are determined from such element-distribution images by application of an objective image segmentation method. By superposition of two or more element-distribution images, mutual element relations are qualitatively established in lysosomal cerium- and barium-containing precipitates connected with acid phosphatase (AcPase) or aryl sulphatase (AS) enzyme activity. By comparing electron spectroscopic images (ESI) with element-distribution images, the mutual contrast per element relations are quantitatively investigated. The obtained gain in resolution in such electron energy-loss spectroscopic element-distribution images will be explained and discussed.

Animals↗
PubMed1992

Light microscopic morphometric analysis of peroxisomes by automatic image analysis: advantages of immunostaining over the alkaline DAB method.

The feasibility of light microscopic post-embedding immunocytochemistry for morphometry of peroxisomes using automatic image analysis was investigated and compared with the classical alkaline DAB method. Perfusion-fixed rat liver tissue was either embedded in LR White or incubated in the alkaline diaminobenzidine (DAB) medium for cytochemical visualization of catalase. Sections from the LR White-embedded material were incubated with a monospecific antibody against catalase, followed by protein A-gold and silver intensification. Determination of peroxisomal volume density in sections of different thickness revealed that the values increased with section thickness in DAB-stained sections but were unaffected in immunostained preparations. Moreover, the absolute value for volume density of peroxisomes, as determined by light microscopy in immunostained sections, was quite close to the value obtained by analysis of electron microscopic preparations. Finally, morphometric analysis of bezafibrate-induced peroxisome proliferation revealed that the ratio of proliferation obtained by light microscopy in immunostained sections was very close to the results obtained by electron microscopic morphometry. The main advantage of post-embedding immunostaining for light microscopic morphometry is that it restricts the immunocytochemical reaction product to the surface of the section, thus making it independent of section thickness.

3,3'-Diaminobenzidine↗
PubMed1992

Subcellular visualization of light microscopic specimens by laser scanning microscopy and computer analysis: a new application of image analysis.

To identify subcellular organelles or to observe their pathological changes in sections prepared for light microscopy, immuno- and/or enzyme histochemical staining for the marker substances or enzymes of those subcellular organelles are frequently employed. With conventional light microscopes (CLM), however, it is hardly possible to determine whether or not the target organelles are properly stained and to confirm their fine structure. In the present study, the laser scanning microscope (LSM) was employed to obtain highly contrasted images of histochemically stained subcellular organelles at the limit of resolution in light microscopy. To refine or characterize those images, images built up as electronic signals in LSM were further processed in the Image Analysis System (IAS) with pipeline. Thus, the approximate figures of subcellular organelles such as microtubules, endoplasmic reticula, secretory granules, and mitochondria were visualized in brightfield on sections prepared for light microscopy (paraffin, frozen sections and cultured living cells). The validity of the images obtained by LSM or LSM-IAS was confirmed by immunoelectron microscopy when possible. The LSM images of histochemically stained suborganelles of various cells were definitely improved (refined and/or strengthened) by processing them with IAS.

Endoplasmic Reticulum↗
PubMed1992

Computer-generated diagnosis and image analysis. An overview.

Image analysis provides quantitative data on morphology, cytochemical and histochemical reactions, the location of specific events or reaction sites, and statistical descriptions of the spatial distribution of such events relative to histologic structure. Image analytic methodology in correlation with histopathologic knowledge bases is an essential component in the development of an objective basis for histopathologic diagnostic decision making.

Humans↗
PubMed1991

DNA analysis of cardiac myxomas: flow cytometry and image analysis.

Cardiac myxoma is the most common primary tumor of heart, but there is a longstanding controversy over whether it is a true neoplasm or a reactive lesion. We analyzed 24 cardiac myxomas from 22 patients: 22 by DNA flow cytometry and five by image analysis. Two myxomas were aneuploid; one of those analyzed by flow cytometry, and the other by image analysis. Proliferative fractions (S + G2/M) were high in three tumors from patients with multiple myxomas (mean, 15.9%; SD, 4.0%) as compared with 12 solitary uncomplicated myxomas (mean, 7.7%; SD, 6.0%). S-phase and proliferative fractions were low in embolic, recurrent, and solitary myxomas. The presence of aneuploidy in some myxomas supports a neoplastic origin for this tumor.

Adult↗
PubMed1982

Early effects of chemical carcinogens as compared to induced cell proliferation. II. Automated image analysis.

Static automated image analysis was applied to study early variations of chromatin structure in Feulgen-stained liver nuclei from rats injected i.p. with a single dose of dimethylnitrosamine (DMNA), a well known hepatocarcinogen. An increase of nuclear area and a correspondent decrease of average optical density (integrated optical density/area) was observed, as compared with controls, in nuclei from rats treated with 5.4 mg/kg of DMNA. These findings, which were comparable with those induced by partial hepatectomy, indicate the existence in DMNA-treated cells of a chromatin DNA relaxation similar to the G0-G1 transition previously described for human diploid fibroblasts stimulated to proliferate. Because similar results were independently obtained by flow microfluorimetry, it seems reasonable to hypothesize that chromatin decondensation could be a prerequisite for cancer induction.

Animals↗
PubMed1992

[Progress in microscopic image analysis and the trend of image cytometry].

Image cytometry has recently developed prominently based on the digital imaging of cell morphology brought about by great advances in microcomputer hardware and software, electronics etc. This method is characterized by the quantitation of both the amount of intracellular bioactive materials and cell morphology, and is expected to further advance many cell analysis techniques involving automated cytology, chromosome image analysis, automated histopathology, viable cell analysis, 3D image construction, etc. The present use is still minimal, and advances in both hardware and software for cyto-histologic recognition are essentially necessary. Perhaps by the end of this century, more sophisticated and faster machines for automated cyto-histologic analysis will appear, replacing many microscopic techniques of presently subjective observation in the biomedical field.

Cell Cycle↗
PubMed1987

The effect of inhaled leukotriene D4, histamine, or antigen on central and peripheral airways of guinea pigs: analysis of bronchograms with an interactive image analysis system.

The effect on guinea pig airways of the inhalation of leukotrienes, histamine or antigen was investigated by measuring changes in lung volume and analyzing the airway area on bronchograms with the Zeiss interactive image analysis system (IBAS). LTC4, LTD4, LTE4 and histamine inhaled through an ultrasonic nebulizer caused inflation of the lung: LTD4 was the most potent of the leukotrienes and was 100 times more potent than histamine on a molar basis. The results of analyses of areas of large and small bronchi and bronchioles on the bronchograms indicated that LTD4 selectively decreased the area of the peripheral airways. Inhalation of an antigen in actively sensitized animals resulted in inflation of the lung and in a selective decrease in the area of the peripheral airways. Anaphylactic bronchoconstriction provoked by antigen inhalation was clearly inhibited by AA-861, a 5-lipoxygenase inhibitor but not significantly by mepyramine, an antihistamine. These observations indicate that LTD4 is a potent constrictor of the peripheral airways in guinea pigs and that the anaphylactic bronchoconstriction provoked by antigen inhalation could be mediated by LTD4 in actively sensitized guinea pigs.

Anaphylaxis↗
PubMed1992

Biotechnological applications of image analysis: present and future prospects.

The current and potential biotechnological applications of image analysis and image processing systems are reviewed. Image analysis systems have proven to be highly versatile and efficient tools for assisting academic biotechnological research. It is expected that image analysis systems will allow more rapid and accurate quantification of numerous biotechnological analyses. There is, therefore, much scope for the implementation of image analysis/processing systems in a large variety of industrial and clinical applications.

Animals↗
PubMed1992

[Image-analysis of salivary tumors].

The image analysis of 49 cases of salivary tumors showed that the cellular DNA content of most tumors (42/49) was diploidy and near diploidy. The heteroploidy rate was only 14.29% (7/49), which may be related to such clinical behaviors of salivary tumors as slow growth, relative low invasivity and metastatic ability. Among these morphologic parameters, nuclear perim and form PE were closely correlated with the malignancy of salivary tumors, the former was positive and the latter was negative. The insignificant nuclear heteromorphous appearance of adenoid cystic carcinoma and its relatively high cellular DNA content may be related to strong invasivity and metastatic ability. In conclusion, these parameters of DNA content and nuclear morphology supplied by image analysis are of value in the diagnosis of salivary tumors.

Adenocarcinoma↗
PubMedDate not supplied

An image analysis workstation designed for multiple users: application of quantitative digital imaging techniques to electron microscopy.

The purpose of the present study is to describe the setup of an image analysis workstation designed for multiple users, and to show the application of digital imaging techniques to the analysis of electron microscopic images. The image analysis system consists of a conventional light microscope mounted on a table-top, vibration-free platform, a light box for viewing negatives, two separate video cameras, a switch box, a video monitor, a digitizing tablet, a computer, and morphometric software packages. The system can quantitate the amount that each of the 256 gray levels contributes to the image, perform morphometric analysis (eg, shape and size) on individual gray level-defined subimages, and perform statistical analysis. Each operator has access to his or her own data and program setups through the use of 21.4-Mb removable Bernoulli cartridges. This setup for multiple users prevents the cluttering of the hard drive of the computer and avoids the possibility of accidentally removing the stored data of another user. The quantitative capabilities of the digital imaging system is demonstrated using an image of a normal lymphocyte and an apoptotic cell (ie, a cell which has undergone programmed cell death), both captured on the same electron microscopic negative. A comparison of the histograms of nuclear densities determined for these two cells reveals subtleties in gray level distribution not appreciated by the naked eye.

Clinical Laboratory Techniques↗
PubMed1989

Comparison of image analysis of imprints with flow cytometry for DNA analysis of solid tumors.

Quantitative analysis of cellular DNA content may be clinically useful for several solid tumors. The technology for this analysis by flow cytometry or image analysis has existed for several years but has not been widely used, except in a handful of specialized research institutions. Recently, however, relatively inexpensive image analyzers intended for use by hospital pathologists have been introduced that can analyze DNA content from cytology or imprint specimens which are readily obtainable from solid tumors. We report here an assessment of this technology for analysis of tumor imprint specimens, using flow cytometry of tissue blocks as the standard for comparison. We used image analysis equipment on Feulgan-stained imprint preparations from 31 tumors and compared the histograms with those obtained by flow cytometric analysis of archival tissue blocks from the same tumors. The ploidy descriptors (diploid, tetraploid, and aneuploid) were concordant for the two methods in 27 specimens, with three specimens yielding discordant results and one specimen considered unevaluable by image analysis. The image analysis method using imprints appeared to have several advantages over flow cytometry, including lower instrument cost, no need to dissociate paraffin blocks or fresh tissue, and ability to analyze very small samples. Somewhat lower resolution of the histograms, extremely localized tissue sampling, and possibly greater risk of occasionally obtaining unevaluable preparations were disadvantages. Microcomputer-based image analysis performed on imprints appeared to be a viable alternative to flow cytometric analysis of tissue blocks for quantitative DNA analysis of tumor specimens.

Aneuploidy↗
PubMed1989

Computer image analysis of toxic fatty degeneration in rat liver.

Fatty degeneration of the liver is one of the most frequently observed pathological changes in the experimental estimation of the toxicity of chemical compounds. The intensity of this kind of damage is most often detected by means of a generally accepted scale of points, whereas the classification is performed according to the subjective "feeling" of the pathologist. In modern pathological diagnostics, computer analysis of images is used to perform an objective estimation of the degree of damage to various organs. In order to check the usefulness of this kind of method, comparative biochemical and morphometrical studies were undertaken in trichloroethylene (TRI)-induced fatty degeneration of the liver. TRI was administered to rats intragastrically, in single doses: 1/2; 1/3; 1/4; 1/6 and 1/18 DL50. 24 hours after the administration, the animals were sacrificed. The content of triglycerides in the liver was determined according to Folch et al. (1956). Simple lipids in the histochemical samples were detected by means of staining with a lipotropic, Fat Red 7B. The area of fatty degeneration was estimated in the microscopic samples by the use of an automatic image analyser IBAS 2000 (Kontron). The morphometrical data concerning the area of fatty degeneration in the liver amplified a high degree of correlation with the content of triglycerides (r = 0.89) and the dose of TRI (r = 0.96). The degree of correlation between the biochemical data and the dose of TRI was 0.88. The morphometrical studies performed have proved to be of great use in estimating the degree of fatty degeneration in the liver. This method enables precise, quantitative measuring of this sort of liver damage in the material prepared for routine histopathological analysis. It requires, however, the application of a specialized device for quantitative image analysis.

Animals↗