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PubMed1990

Image analysis of endodontic radiographs: digital subtraction and quantitative densitometry.

In this study computerized image analysis procedures were applied to endodontic radiographs. Kontron IBAS 2000 is a commercially available image analysis system with processing routines applicable to radiograph digitizing and transformations. The system was evaluated for: its ability to harmonize blackening and contrast in endodontic radiographs; its ability to compensate for angulation distortion of sequential exposures of individual teeth; its potential for application of digital subtraction methods; and its use in automated gray-level analyses of diseased and healthy bone areas in endodontic radiographs. The Kontron IBAS 2000 system proved suitable for all applications. However, the specificity of the subtraction procedure was limited by some inherent problems in the harmonization of blackening and in the subtraction process itself. On the other hand, automated gray level measurements proved to be a robust method for unbiased and quantitative assessment of healing of apical periodontitis.

Absorptiometry, Photon↗
PubMed1990

[Automatic microscopic image analysis of semithin sections of peripheral nerves using the program Image-C/Nerve-Neuropathy].

Visiomanual morphometric analysis of peripheral nerve fibres has proved to be error-laden and inadequate. An automatic interactive programme was, therefore, developed for microscopic image analysis and feature extraction. Contours of myelin sheaths were properly identifiable, but an interactive programme component was found to be required to measure the remainder of two to 5% of fibres. Image analysis is shown to generate descriptive statistical features.

Humans↗
PubMedDate not supplied

Semiautomated ROI analysis in dynamic MR studies. Part I: Image analysis tools for automatic correction of organ displacements.

The most important problem in the analysis of time sequences is the compensation for artifactual motion. Owing to motion, medical images of the abdominal region do not represent organs with fixed configuration. Analysis of organ function with dynamic contrast medium studies using regions of interest (ROIs) is thus not readily accomplished. Images of the organ of interest need to be registered and corrected prior to a detailed local analysis. We have developed an image analysis scheme that allows the automatic detection of the organ contours, the extraction of the motion parameters per frame, and the registration of images. The complete procedure requires only minimal user interaction and results in a readjusted image sequence, where organs of interest remain fixed. Both a visual analysis of the dynamic behavior of functional properties and a quantitative statistical analysis of signal intensity versus time within local ROIs are considerably facilitated using the corrected series.

Algorithms↗
PubMed1996

[Minimal change disease and focal segmental glomerulosclerosis in children--histomorphometric comparative study with application to computer image analysis].

The authors evaluated, using computer image analysis system, 15 renal biopsy specimens from patients with MCD and 15 from patients with FSGS. As a control group 5 biopsy and 10 autopsy renal specimens were used. These studies revealed, that in MCD glomeruli showed proliferative changes unrecognizable by light microscopy. In FSGS glomeruli without sclerotic changes were larger than in controls and showed glomerular cells proliferation (per unit of glomerular area) similar to MCD. FSGS in comparison with MCD showed larger glomeruli and prominent interstitial fibrosis. These observations appeared to be helpful in distinguishing MCD and recent forms of FSGS. There were no correlations between relative interstitial volume and glomerular changes in MCD as well as in FSGS. The authors concluded, that histomorphometry can't be used instead of morphological examinations of renal biopsy specimens, but it gives objective informations about progression of the illness and may be useful in differential diagnosis of selected cases of MCD and FSGS.

Biopsy↗
PubMed2006

Time-variant analysis of fast-fMRI and dynamic contrast agent MRI sequences as examples of 4-dimensional image analysis.

OBJECTIVES: Image sequences with time-varying information content need appropriate analysis strategies. The exploration of directed information transfer (interactions) between neuronal assemblies is one of the most important aims of current functional MRI (fMRI) analysis. Additionally, we examined perfusion maps in dynamic contrast agent MRI sequences of stroke patients. In this investigation, the focus centers on distinguishing between brain areas with normal and reduced perfusion on the basis of the dynamics of contrast agent inflow and washout. METHODS: Fast fMRI sequences were analyzed with time-variant Granger causality (tvGC). The tvGC is based on a time-variant autoregressive model and is used for the quantification of the directed information transfer between activated brain areas. Generalized Dynamic Neural Networks (GDNN) with time-variant weights were applied on dynamic contrast agent MRI sequences as a nonlinear operator in order to enhance differences in the signal courses of pixels of normal and injured tissues. RESULTS: A simple motor task (self-paced finger tapping) is used in an fMRI design to investigate directed interactions between defined brain areas. A significant information transfer can be determined for the direction primary motor cortex to supplementary motor area during a short time period of about five seconds after stimulus. The analysis of dynamic contrast agent MRI sequences demonstrates that the trained GDNN enables a reliable tissue classification. Three classes are of interest: normal tissue, tissue at risk for death, and dead tissue. CONCLUSIONS: The time-variant multivariate analysis of directed information transfer derived from fMRI sequences and the computation of perfusion maps by GDNN demonstrate that dynamic analysis methods are essential tools for 4D image analysis.

Cerebrovascular Circulation↗
PubMed2006

[Evaluation of therapeutic effects of Chinese materia medica by tongue image analysis software 1.0 based on tongue colors].

OBJECTIVE: To evaluate the therapeutic effects of Chinese materia medica in treating patients with different syndromes by tongue image analysis software 1.0 based on tongue colors, and to discuss the feasibility of applying this computer science-based techniques into drug evaluation. METHODS: The tongue colors and the areas of tongue fur were examined and analyzed by the tongue image analysis software 1.0 in healthy persons and the patients with different syndromes before and after treatment. The parameters of tongue colors consisted of the followings: the hue (H), the lightness (L), the saturation (S), and the values of red (R), green (G) and blue (B). RESULTS: Obvious differences could be revealed in tongue color index between the healthy persons and the patients in five groups of different syndromes. There also existed some significant differences in those index between patients before and after treatment. CONCLUSION: The tongue image analysis software 1.0 based on tongue colors is helpful to evaluate the therapeutic effects of Chinese materia medica.

Adolescent↗
PubMed1993

Common acquired melanocytic nevi, dysplastic melanocytic nevi and malignant melanomas: an image analysis cytometric study.

We used computerized image analysis cytometry to analyze 10 melanocytic lesions from each of the following categories: common acquired nevi, melanocytic nevi with architectural features of dysplasia, dysplastic melanocytic nevi (DMN) with slight atypia, DMN with moderate atypia, DMN with severe atypia, and superficial spreading melanomas. The nuclei of at least 50 consecutive nevomelanocytes in the most atypical zones were digitized at x 1000 under oil immersion, without knowledge of diagnosis by one observer. Grading of atypia was based on current practices as described in the literature. The results showed significant differences (p < 0.05) in nuclear area and standard deviation of nuclear area between melanoma and DMN with severe atypia, and between DMN with severe atypia and all other categories of nevi. There were no differences among any lesions with respect to nuclear shape. No differences in nuclear area were found among DMN with moderate, or slight atypia, nevi with features of dysplasia, and typical nevi. These results show for the first time objective distinction of low-grade (slight-moderate atypia), and high-grade or severe atypia in pre-malignant nevomelanocytic lesions of the skin.

Humans↗
PubMed1990

Image analysis cytometry of dysplastic nevi.

Computerized image analysis was used to assess nuclear atypia in 24 dysplastic nevi (DN), 19 CN (CN), and five thin melanomas. DN were selected for the study using architectural criteria alone. Feulgen-stained, 6-um sections were analyzed with a microTICAS cytometer. At least 100 nuclei were measured in each case. The standard deviation of nuclear area, mean nuclear roundness, standard deviation of nuclear roundness, mean ploidy, and standard deviation of ploidy were found to be significantly greater for DN than for CN. DNA histograms from DN showed an increased fraction above 2N, suggesting that DN are more proliferative than CN. No DN were aneuploid. All melanomas were aneuploid, and differed significantly from DN in mean nuclear area, standard deviation of nuclear area, mean ploidy, and standard deviation of ploidy. There were no significant differences between the junctional and intradermal populations of compound DN in any of the measured parameters, except that the intradermal nuclei were significantly rounder than the junctional nuclei. There were no significant differences between DN from patients with only a single DN and DN from patients with at least two dysplastic nevi.

Cell Nucleus↗
PubMed1997

Application of computer image analysis in endocrine cell quantification.

Computer image analysis was applied for quantifying endocrine cells by using an automatic standard sequence analysis operation. Two parameters were used, namely the number of cells per mm3 of epithelial cells and the cell secretory index (the volume of the immunoreactive secretory granules per cell). The first indicates the variation in the anatomical peptide-producing unit and the second the synthesis and secretion activity of the cell. The endocrine cells chosen in this study were chromogranin-immunoreactive cells and secretin-immunoreactive cells in the human duodenum. The measurements were made by five different investigators with different backgrounds in order to evaluate the effect of the intra- and inter-individual variation. This study showed that the intra- and inter-individual variation had no impact on the results. Comparisons with the classical point-counting method considered to be easy and most efficient in volumetry showed that the present approach is between two and three times faster and less strenuous for the performer. It is concluded that this approach seems to be suitable for adaptation in morphometric studies when information is required about the changes in the number of endocrine cells and about changes in secretory activities.

Adult↗
PubMedDate not supplied

Extracted image analysis: a technique for deciphering mediated portrayals.

A technique for analyzing print media that we have developed as a consequence of our interest in the portrayal of women in menstrual product advertising is reported. The technique, which we call extracted image analysis, involves a unique application of grounded theory and the concomitant heuristic use of the concept of ideal type (Weber, 1958). It provides a means of heuristically conceptualizing the answer to a variant of the "What is going on here?" question asked in analysis of print communication, that is, "Who is being portrayed/addressed here?" Extracted image analysis involves the use of grounded theory to develop ideal typologies. Because the technique re-constructs the ideal types embedded in a communication, it possesses considerable potential as a means of identifying the profiles of members of identifiable groups held by the producers of the directed messages. In addition, the analysis of such portrayals over time would be particularly well suited to extracted image analysis. A number of other possible applications are also suggested.

Female↗
PubMed2006

Digital image analysis for morphometric evaluation of tissue response after implanting alloplastic vascular prostheses.

The aim of this study was to examine the suitability of digital image analysis, using the KS400 software system, for the morphometric evaluation of the tissue response after prosthesis implantation in an animal model. Twenty-four female pigs aged 10 weeks were implanted with infrarenal Dacron(R) prostheses for 14, 21, 28, and 116 days. Following the explantation and investigation of the neointima region, the expression of beta-1-integrin, the proliferation rate by means of Ki-67 positive cells, and the intima thickness were evaluated as exemplary parameters of the tissue response after implantation. Frozen tissue sections were immunohistochemically stained and subsequently examined using computer-aided image analysis. A maximum expression of 32.9% was observed for beta-1-integrin 14 days after implantation, gradually declining over time to 9.8% after 116 days. The proliferation rate was found to be 19% on day 14, increasing to 39% on day 21 with a subsequent gradual decline to 5% after 116 days. The intima thickness increased from 189.9 microm on day 14 to 1228.0 microm on day 116. In conclusion, digital image analysis was found to be an efficient and reproducible method for the morphometric evaluation of a peri-prosthetic tissue response.

Animals↗
PubMed1989

Digital image analysis in cytological diagnosis: a morphometric analysis on pleural mesotheliomas.

In the course of the last years digital image analysis has become increasingly important in the field of quantitative pathology. This may be due to the technical development of computers which have now reached a high user-friendly standard. In the present paper we present: (1) the development of a simple system for the measurement of digital image analysis; (2) the development of a general data structure applicable to various measurements and classification strategies; and (3) the analysis of the value of invariant moments (IM) as regional descriptors to distinguish mesothelial cells from mesothelioma cells in cytologic smears of pleural fluid. The results show that the invariant moments contain information concerning the geometric distribution of the grey values of the pixels as well as the staining intensity. The invariant moments present combination parameters and are therefore ideal morphometric parameters. With the invariant moments 7 out of 7 patients with mesotheliomas and 8 out of 11 control subjects could be assigned correctly in a nonparametric discriminant analysis procedure.

Cell Nucleus↗
PubMed1985

Detection of increased pallor over time. Computerized image analysis in untreated ocular hypertension.

Computerized image analysis was used to measure changes in percent area of pallor of the optic disc in a retrospective study of a group of 16 normals and 39 untreated ocular hypertensives. The optic discs of the subjects were photographed on at least two visits at least one year apart (mean, 2 years). No significant changes in area of pallor for the normal group were observed between visits, except in the inferior quadrant of the left eye. The ocular hypertensive group showed a significant increase in area of pallor between visits for the total disc and for most quadrants of both eyes. Multiple regression analysis revealed that, in addition to ocular hypertension, the significant factors associated with a change in optic disc pallor were change of ocular pressure, standard deviation of the ocular pressures, presence of vascular hypertension, and standard deviation of vascular pulse pressures. Clinical implications of early detection of disc changes for follow-up and treatment of ocular hypertensives are discussed.

Adult↗
PubMed1989

[Application of nuclear image analysis to diagnosis in oncology].

Cell image analysis applied to Feulgen stained cells allows description of each nucleus according to 15 parameters which measure DNA content, shape and size of the nucleus, as well as chromatin texture and distribution. We have studied the effects of hormones or chemotherapy on human and murine mammary cancer cell lines and on an in vivo murine mammary tumor. The method was then applied to different kinds of human cancers and proved to bring consistent results with anatomopathological grading (breast, colon, bladder), with estrogen receptor content (breast) and with molecular tumor marker (hybridization to the 16 or 18 papilloma virus in uterine cervix dysplasia).

Animals↗
PubMed1997

Computerized image analysis of morphologically transformed and nontransformed Syrian hamster embryo (SHE) cell colonies: application to objective SHE cell transformation assay scoring.

We have developed an automated image analysis system that provides comparable classification of morphologically transformed SHE cell colonies to the current visual classification method used in the in vitro SHE cell transformation assay. Visual classification of morphologic transformation in this assay has been shown to accurately predict the carcinogenic potential of chemical, biological and physical agents. The image analysis system is quantitative, based on measuring features of colony color, texture and growth patterns. A linear combination of feature measurements produces a classification process that agrees with visual assessment 93% of the time. All identifiable sources of error are explored and the method is found to be robust in analyzing nearly 500 colonies from a variety of studies performed over a one year period. The high degree of correlation between the visual classification and the objective measurements of the image analysis system validates the reproducibility of the visual scoring process and serves as a basis for automation of the assay.

Animals↗
PubMed1999

Digital image analysis of silver-stained nucleolar organizer region--associated proteins in endometrial cytologic samples.

OBJECTIVE: Digital image analysis was applied to determine the number, area and size of silver-stained nucleolar organizer regions (AgNORs) in cytologic samples from curettage in normal, hyperplastic and malignant endometrium. STUDY DESIGN: Thirty-two archival cytologic smears from curettage (previously stained by the Papanicolaou method) with the histologic diagnosis (4 inactive endometrium, 5 secretion, 5 proliferation, 5 simple hyperplasia, 5 complex hyperplasia, 3 atypical hyperplasia, 5 adenocarcinoma, grade 1) were analyzed with the AgNOR technique. Count, area and size of AgNORs were analyzed in 50 cells per sample using a magnification of 1,000x. Quantitative analysis was performed on an SFORM digital imaging system. Data were analyzed with the SPSS/PC+ program. Mann-Whitney and chi 2 tests were performed. RESULTS: The average value of AgNOR count increased from normal to hyperplastic endometrium and well-differentiated adenocarcinoma. Differences were significant except between atypical hyperplasia and adenocarcinoma. Four, five and more AgNORs in 40% or more of the nuclei were found in complex and atypical hyperplasia and adenocarcinoma. Proliferation, and simple and atypical hyperplasia had similar mean values of AgNOR area. The mean total AgNOR area value increased from normal to hyperplastic had similar mean values of AgNOR area. The mean total AgNOR area value increased from normal to hyperplastic and well-differentiated adenocarcinoma. Differences were statistically significant. AgNOR size in well-differentiated adenocarcinoma was significantly different from that in normal endometrium and different grades of hyperplasia. CONCLUSION: Digital image analysis of AgNOR count, area and size enabled a distinction to be made between normal, hyperplastic and malignant endometrium.

Adenocarcinoma↗
PubMed1999

Image analysis of implanted rigid and foldable intraocular lenses in human eyes using Scheimpflug photography.

We evaluated the quality of imaging posterior chamber intraocular lenses (PC IOL) by Scheimpflug photography. We took photographs of 190 rigid or foldable PC IOLs using the Scheimpflug system EAS-1000 from Nidek and provided digital image analysis. We found a good imaging of PC IOLs and the cristalline lens capsule, data obtained by digital image analysis were reliable and reproducible and Scheimpflug photography could be demonstrated as a sensitive tool to show any irregularities of IOL material. Thus, we found in foldable IOLs 'glistenings', which did not have any influence on functional results and we could distinguish them from lens damage. We propose to use Scheimpflug tests regularly for the examination of implanted new types of IOLs.

Humans↗
PubMed1998

Objectivity of two methods of differentiating fibre types and repeatability of measurements by application of the TEMA image analysis system.

The objectivity of two of the most widely used methods for differentiation of fibre types, i.e. 1) the myosin ATP-ase method (Brooke and Kaiser, 1970a,b) and 2) the combined method, by which the myosin ATP-ase reaction is used to differentiate between fast and slow twitch fibres and NADH-tetrazolium reductase activity is used to identify the subgroups of fast twitch fibres (Ashmore and Doerr, 1970, Peter et al., 1972), was assessed in muscle samples from horses, calves and pigs. We also assessed the objectivity of the alpha-amylase-PAS preparation for the visualisation of capillaries (Andersen, 1975) in these species. For the purpose of reducing the time costs of histochemical analysis of muscle samples, we have developed an interactive image analysis system which is described. All analyses are performed on this system. In accordance with several other investigations, differences between the two methods of differentiating fibre types were found only for the relative distribution of the fast-twitch fibre subgroups (p < 0.02 and p < 0.05 for the relative number of type IIA and IIB, respectively) whereas when calculated in relative area, only the proportion of type IIA fibres differed significantly (p < 0.05). Significant interaction effects between method and person and method and species were found for the same traits. When methods were analysed separately, the combined method displayed a significant variance component of person for the distribution of type IIA fibres both in relative number and in relative area (p < 0.01 and p < 0.001, respectively). The objectivity of the ATP-ase method was further substantiated by the fact that a higher fraction of the total variance for the relative area distribution of type IIA fibres was explained by the statistical model (72.1% versus 34.2% for the combined method). Although the repeatability of measurements between persons was generally high (> 87%), the impact of differences in pre-requisites (varied degrees of overlap between the fibre types) for performing the differentiation by the combined method raises a question of the reliability of this method. Apparently, no general rules for comparison of results of distribution of the two subgroups of fast twitch fibres by the two methods are applicable. The alpha-amylase-PAS method was found to be a fairly objective method to identify capillaries in muscles from horses, calves and pigs. However, as capillarity described in combination with other traits to give an indication of diffusion characteristics is significantly influenced by person, it is recommended that the same person perform all the analysis of a project. In addition to the methodological results in this study, we have shown that by application of the TEMA image analysis system, which is more rapid compared with the time-consuming traditional method for evaluation of histochemical preparations, analysis of samples from large-scale experiments are now possible.

Animals↗