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PubMed1993

The histologic spectrum of apocrine breast proliferations: a comparative study of morphology and DNA content by image analysis.

Apocrine features occurring in sclerosing adenosis (apocrine adenosis), atypical ductal hyperplasia (ADH), and non-comedo ductal carcinoma in situ (DCIS) often add to diagnostic difficulty. We have evaluated the usefulness of DNA content determined by image analysis in apocrine metaplasia and hyperplasia, apocrine adenosis, ADH, DCIS, lobular carcinoma in situ, invasive ductal carcinoma, and infiltrating lobular carcinoma as a potential diagnostic aid in some of these problematic breast lesions with apocrine features. Infiltrating ductal carcinoma and DCIS were further subdivided into high- or low-grade category based on nuclear features. Microscopic fields containing 63 lesions were identified in slides from breast excisions. From each selected area 100 cells in corresponding fields in paired Feulgen-stained sections were digitized for computerized ploidy analysis with lymphocyte nuclei in the same slides serving as internal diploid controls. Aneuploidy was assessed using combined DNA index and modified Auer histogram criteria for DNA content abnormalities. There was strong association between the assessment of nuclear grade and ploidy (Fisher's exact test, P < .00001). All but one of the benign and low-grade malignant lesions (97%) were in the diploid range (six of seven apocrine metaplasia cases, three of three apocrine adenosis cases, 14 of 14 ADH cases, 10 of 10 low-grade DCIS cases, two of two lobular carcinoma in situ cases, and two of two infiltrating lobular carcinoma cases). In contrast, 24 of 25 (96%) of the high-grade malignant lesions were aneuploid (10 of 10 DCIS cases and 14 of 15 infiltrating ductal carcinoma cases). We conclude that DNA ploidy status does not offer additional diagnostic information to light microscopy in distinguishing among benign apocrine proliferations, ADH, and low-grade DCIS since these proliferations share a diploid range DNA content.

Breast Neoplasms↗
PubMed1986

Measurement method of the anterior chamber volume by image analysis.

A new computerised method of measurement of the anterior chamber in the human eye is described. Photographs of the anterior chamber were taken with a Zeiss slit-lamp 75-SL and converted from an optical image into a true image by computer with a digitiser. We obtained data on both the anterior chamber volume and also the anterior chamber depth, peripheral anterior chamber volume, the diameter of the anterior chamber, and the degree of the iridocorneal angle. These data were simultaneously displayed several seconds after in-put by the digitiser. In mensuration by digitiser on three occasions from a single photograph of a given eye the mean deviation rate was about 0.7%, and the mean deviation rate of 10 successive exposures of one eye was 3.5%. By this image analysis technique an accurate profile of the anterior chamber is displayed of the pupil margin, iris-root insertion, and central anteroposterior pupillary axis. These data help us to understand the mechanism of primary angle-closure glaucoma.

Anterior Chamber↗
PubMed2005

Automated image analysis of bacterial colony growth as a tool to study individual lag time distributions of immobilized cells.

A method to determine the individual lag time (lag) distributions of immobilized bacteria was presented. The method was based on the image analysis of the bacterial colony growth. The lag distributions were retrieved from the distributions of the detection times (Td) required to form macroscopically visible colonies. Using this method, the lag distributions on agar for Listeria monocytogenes cells previously subjected to two situations reproducing conditions encountered during the contamination of cheese, were determined. The results were presented and compared with lag distributions obtained with an established method based on the time to detection of turbidity in broth. An original method to retrieve lag in broth and agar without any knowledge of the growth rate was also proposed. In order not to bias the distributions of lag on agar the impact of spatial separation between colonies on colony growth rates was quantified. Means and standard deviations of lag distributions for the two different stresses were found to be similar in broth and on agar. Extreme Value type II distributions fitted the best the different datasets of lag distributions.

Agar↗
PubMed1986

[Grading of urinary bladder tumors by automated microscopic image analysis].

Studies were undertaken on biopsies from urinary bladder papillomas and urothelial carcinomas of different grades (G1-G3) along with normal urinary bladder mucosa from a total of 145 patients. They were performed by use of automated microscopic image analysis (system Robotron A 6471; software AMBA/R) and resulted in making objective the tumor grading and lead to the detection of both papillomas and G1-carcinomas with high proliferating activity. In addition, we were able to separate the G2-carcinomas into two groups which probably show different biological behaviour. They cannot be discriminated by conventional morphological methods but their existence is consistent with clinical observations.

Aged↗
PubMed1988

Real-time scanning and image analysis. A fast method for the determination of neutrophil orientation under agarose.

We describe a newly developed method for fast determination of neutrophil chemotaxis and orientation in concentration gradients of chemotactic factors. The system implements video-based real-time scanning and image analysis of neutrophil migration under agarose, using an interactive easy-to-use computer program. Two methods for determining cell orientation are presented. No statistically significant difference between the methods was found. The analysis program distinguishes between chemokinetic and chemotactic behaviour of the cells (P less than 0.01).

Algorithms↗
PubMed1996

Reliability of computer image analysis of pigmented skin lesions of Australian adolescents.

BACKGROUND: The diagnosis of melanomas at an early stage is associated with improved survival, so the recognition of changes in pigmented skin lesions over time is important. We have developed a computer imaging system with the aim of assisting clinicians in differentiating early melanomas from benign pigmented skin lesions. The objective of this study was to investigate the system's reliability over time in measuring diagnostic characteristics of pigmented skin lesions, including their color, size, shape, and distinctness of boundary. METHODS: We captured video images of 5 lesions, all larger than 2 mm in greatest dimension, on each of 66 Australian adolescents on 2 occasions approximately 1 month apart. Features extracted by computer image analysis included area, perimeter, and regularity of outline of the lesions, the mean and standard deviation of reflectance at red, green, and blue wavelengths, and the mean and standard deviation of the gradients of red, green, and blue reflectance at the lesion boundary. RESULTS: All measurements showed moderate to high reliability (intraclass correlation coefficients 0.66-0.94), except for the standard deviations of the color gradients, whose reliability improved to moderate levels (0.68-0.71) when the mean of 5 lesions was considered. For most outcomes, reasonable within subject reliability was achieved when five lesions per subject were measured. CONCLUSIONS: These results, in combination with previous work demonstrating the reasonable ability of this computer imaging system to discriminate between malignant melanomas and other pigmented lesions, indicates that the system has the potential to become a useful tool for clinicians in following people with pigmented lesions over time to detect early malignant changes.

Adolescent↗
PubMed1997

The use of computer-assisted video image analysis for the quantification of CD8+ T lymphocytes producing tumor necrosis factor alpha spots in response to peptide antigens.

Enzyme-linked immunospot (ELISPOT) analysis is a sensitive technique for the detection and quantification of single T lymphocytes forming cytokine spots after antigen contact in vitro. Herein computer-assisted video image analysis (CVIA) was applied to automatically determine the number and size of tumor necrosis factor alpha (TNF-alpha) spots formed by single blood-derived CD8+ T cells after contact with peptide-loaded target cells. With CVIA and TNF-alpha ELISPOT analysis we quantified CD8+ T cells responsive to HLA-A2.1-binding tyrosinase and influenza matrix peptides in healthy donors. We followed the course of the virus-specific T cell response in two HLA-A2-positive patients with reactivation of latent cytomegalovirus (CMV) infection during immunosuppressive therapy. The test proved sufficiently sensitive to detect in the blood of both patients a temporary expansion of CD8+ T lymphocytes reactive with a known immunogenic HLA-A2.1-binding peptide from glycoprotein B of CMV. Reactivity to peptide antigens was not only reflected by numeric increases of spot formation, but also by the appearance of larger spot areas, presumably formed by strongly peptide-reactive CD8+ T cells. We conclude that the combined use of the TNF-alpha ELISPOT assay and CVIA allows reliable monitoring of the T cell responsiveness to peptide antigens in peripheral blood.

Adult↗
PubMed1997

Acceptability and usage patterns of an image analysis workstation.

Critical to the successful deployment and use of new computer systems is the acceptance of the system by the users, i.e., the clinicians. We describe a study which evaluated, in an experimental setting, the potential acceptability of an image analysis workstation for radiation therapy. The acceptability and usage patterns were measured using semi-structured questionnaires and maintaining logs of user interactions. The results of the study showed that the radiation oncologists, who were the subjects for the study, perceived the workstation as acceptable. The results also suggested several areas for improvement of workstation that could increase its acceptance in the clinical setting.

Attitude of Health Personnel↗
PubMed1995

Morphometry of the optic nerve and retinal vessels in children by computer-assisted image analysis of fundus photographs.

BACKGROUND: The retinal fundus in childhood has a different morphology than in adulthood. Existing methods are not suitable for evaluation of fundus photographs from children. Therefore, a new method for quantitative analysis of fundus morphology utilizing a personal computer-assisted digital mapping system was developed. METHODS: A CCD flatbed scanner is used to digitize fundus photographs, producing computer images which are analyzed on an IBM/AT computer. Area measurements of the optic disc, excavation and peripapillary crescent are made, as well as determinations of the length, branching, tortuosity and distribution of the retinal vessels on the fundus surface. RESULTS: Determination of the inter- and intra-observer variability of the computer-assisted image analysis technique demonstrated good reproducibility. The method is demonstrated using fundus photographs of six normal children and six children with the fetal alcohol syndrome. Typical variations in appearance of optic disc and retinal vessels are seen. CONCLUSION: The system is unique in measuring both the optic nerve head and the retinal vessels and is therefore especially useful for detailed studies of normal and abnormal development of these structures in children.

Adolescent↗
PubMed1997

Cell-specific respiratory activity of aquatic bacteria studied with the tetrazolium reduction method, cyto-clear slides, and image analysis.

We present an improvement of the INT [2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyltetrazolium chloride)] reduction method using Cyto-Clear slides, the fluorochrome DAPI (4(prm1),6(prm1)-diamidino-2 phenylindole), and an image analysis system. With this method we were able to simultaneously measure cell dimensions and formazan crystals as indicators of the respiratory activity of single bacteria. The method was tested on a natural bacterioplankton community of an oligotrophic high mountain lake (Gossenkollesee, Tyrolean Alps, Austria, 2,417 m above sea level) in midwinter ((symbl)1-m-thick ice and snow layer; dissolved organic carbon, 0.51 mg liter(sup-1); water temperature, 2(deg)C). About 25% of planktonic bacteria were respiratorily active, and a complex pattern of bacterial morphologies and specific respiratory activities was observed during a time series of INT incubation. Rod-shaped bacteria with cell lengths of between 1.6 and 4.8 (mu)m already showed visible activity after 0.5 h of INT incubation. Small cells (rods and cocci) in the size fraction <1.6 (mu)m and long filamentous bacteria (up to 120 (mu)m) were visibly active only after a 2-h incubation period. After 8 h of incubation, more than 90% of all cells between 3.2 and 6.4 (mu)m in cell length were respiratorily active, whereas only 5% of cells <1.6 (mu)m and 50% of filamentous bacteria contained formazan grains. We could distinguish five major bacterial phenotypes that showed distinct activity patterns with respect to incubation period and numbers and sizes of formazan crystals. There was no correlation between the total formazan volume per active cell and bacterial cell volume, and for any size class of active bacteria, total formazan volumes varied by about 2 orders of magnitude after 8 h of incubation. This indicates that cell-specific activity is extremely variable and is not related to size and that a small portion of all cells may account for the overall activity.

Journal Article↗
PubMed1989

Kinetochore size variation in mammalian chromosomes: an image analysis study with evolutionary implications.

The kinetochore, a proteinaceous plate that is the site for attachment of spindle microtubules to the metaphase chromosome, can be visualized using anti-kinetochore indirect immunofluorescence. We have used computer-assisted image analysis to measure the variation of kinetochore surface areas, as reflected by immunofluorescence areas, in cell lines derived from rat kangaroo, Chinese hamster and common rat, to determine if our size estimates correlate well with those obtained using measurements from electron micrographs. In addition, we used male and female human fibroblast cell lines, as well as a transformed human female cell line as well as a transformed human female cell line (HeLa), to examine kinetochore size variation among cells, between sexes, and between cell lines. We found that our system gave reproducible estimates of kinetochore size, and that these sizes correlated very well (r = 0.95) with the electron micrograph measurements. In examining variation within humans, we observed measurable differences between cell lines. Despite this difference, all the human lines had size distributions that were leptokurtotic and positively skewed. The fact that very few chromosomes exhibited areas smaller than the mode gives support to the idea that mammalian chromosomes may require a specific, minimum amount of kinetochore material in order to maintain stable attachment to the mitotic spindle. On the other hand, the positive skewness seems to indicate that larger kinetochores, possibly the result of events such as Robertsonian fusions, are fully functional. The retention of this plasticity may allow the chromosomes to maintain an evolutionary adaptability that might otherwise be lost.

Animals↗
PubMed2003

Quantitation by image analysis of global DNA methylation in human spermatozoa and its prognostic value in in vitro fertilization: a preliminary study.

OBJECTIVE: To determine the relationship between sperm DNA methylation level and sperm characteristics and pregnancy rates. DESIGN: Prospective study. Quantitation by image analysis of DNA methylation in sperm nucleus. SETTING: Department of Reproduction Biology, Edouard Herriot Hospital, Lyon, France. PATIENT(S): Infertile couples undergoing IVF-ET. INTERVENTION(S): The immunostaining of 5 methyl-cytosine was performed on the spare sperm suspension that was used for an assisted reproduction technology procedure. MAIN OUTCOME MEASURE(S): Sperm characteristics according to World Health Organization criteria, sperm motility parameters with computer-assisted semen analysis, sperm DNA methylation level, and heterogeneity index (HI). RESULT(S): Sperm DNA methylation level and HI are correlated with sperm DNA characteristics. HI is negatively correlated with fertilization rate; sperm DNA methylation level is correlated with pregnancy rate. CONCLUSION(S): The DNA methylation level in human spermatozoa could be a new approach to evaluating the ability of spermatozoa to fertilize and lead to normal embryo development.

3,3'-Diaminobenzidine↗
PubMed1999

Interactive classification of porcine Eimeria spp. by computer-assisted image analysis.

Digitalized pictures of oocysts of Eimeria scabra, E. polita, E. debliecki, E. suis, and E. porci were used to develop a program routine that allows semi-automatic interactive classification of porcine Eimeria spp. with a computer-assisted image analysis system. Morphological parameters (shape, color, length and width of oocysts and length and width of sporocysts) were assayed, transformed to color and shape factors and used to calculate classification indices (G1, SP). Thresholds were defined for these indices to allocate oocysts to groups of species and successively to single species. In more than 97% of cases the program routine allocated digitalized oocysts (n = 175) to the respective species. E. suis was always correctly classified. Interactive classification proved to be convenient, fast, precise and largely free of individual bias.

Animals↗
PubMed1990

Evaluation of nucleolus organizer regions (NORs) by automatic image analysis: a contribution to standardization.

This study summarizes our experiences with the silver staining of nucleolus organizer regions (AgNORs) in a total of 580 tumours from ten different tissues. In contrast to other investigators, we made use of automatic image analysis for the evaluation of AgNORs. This provided good reproducibility as determined by the standard cumulative means technique and intra-observer (r1) and inter-observer (r2) agreement in 30 benign (r1 = 0.83-0.95, r2 = 0.76-0.92) and 50 malignant tissue samples (r1 = 0.72-0.85, r2 = 0.51-0.78). By using a series of staining times on sections from 30 tissue blocks taken from the ten types of tissue investigated, considerable variation in the argyrophilic staining of NORs in different tissues and in different blocks from one tumour was shown. The mean AgNOR area of resting lymphocytes or connective tissue cells within tissue blocks of the same organ system varied up to four-fold, even though identical staining times had been used. The most suitable silver reaction time which rendered a good diagnostic difference in the AgNOR content of benign and malignant tissue ranged, for example, in the breast cancer specimens, from 23 to 35 min. We therefore conclude that the staining time has to be adjusted to the individual silver-binding characteristics of each tissue block or even each section. The use of internal staining standards like lymphocytes or connective tissue cells in the same tissue section is mandatory. This, in turn, is most precisely controlled by morphometry.

Humans↗
PubMedDate not supplied

Computer image analysis of two-dimensional crystals of beef heart NADH: ubiquinone oxidoreductase fragments. II. Comparison of frozen hydrated and negatively stained specimens.

Two-dimensional crystals of bovine NADH: ubiquinone oxidoreductase fragments were studied by cryo-electron microscopy and computer image analysis at two focus settings. The lattice parameters of the crystals were determined as a = 14.5 +/- 0.2 nm, b = 14.8 +/- 0.3 nm with gamma = 87.8 degrees +/- 0.2 degrees. Translation and rotation alignment resulted in a final resolution of 1.38 (close-to-focus) or 1.9 nm (1.3 microns underfocus). When only translational alignment was employed 1.6 nm resolution resulted (close-to-focus case). The application of a further correction procedure surprisingly lowered the achieved resolution to 2.2 nm. A combination of the projected structures for the two focus settings in Fourier space resulted in a noise-free image displaying enhanced image contrast for reciprocal spacings from 1/5.0 to 1/1.4 nm-1. The structure in amorphous ice comprises four separate quasi-identical motifs, each resembling a distorted triangle. Two symmetry-related (p2) motifs reveal a pore-like feature. In negative stain the structure has p4mm symmetry. The absence of in-plane symmetry elements (i.e. twofold rotation and screw axes) and other differences might be accounted for (at least in part) if the crystal studied was slightly tilted.

Animals↗
PubMed1995

[Establishment of three-dimensional finite element models by using a series of plane section images processed with an image analysis system].

The geometric similarity and mesh dividing of finite element models directly create an effect on the results of analysis when a theoretical stress analysis is performed by the use of finite element method. The model is routinely established by means of sectioning the specimen. In this paper, a series of plane section CT images of the teeth and mandible, an image analysis system and a specially designed software for modeling three-dimensional finite element were used to establish a three-dimensional finite element model. It is a new preprocessing method for finite element applications in the field of oral biomechanism. The technique is characterized by the advantages of high similarity of the model to specimens and no damage to specimens; it is simple and easy. The images and figures can be repetitively used.

Biomechanical Phenomena↗
PubMed1998

An automatic image analysis system for RLGS films.

The RLGS (Restriction Landmark Genome Scanning) method was originally developed as a powerful method for enabling viewing of thousands of restriction landmarks. It offers a tool for obtaining information about genetic loci, with a single RLGS profile displaying approximately 2000 restriction landmarks as spots. One of the most useful applications is RLGS spot mapping, which allows the efficient, low-cost construction of the genetic map of any organism. However, analyses of the profiles depend mainly on human visual observation and are tedious and laborious. Although several commercially available image analyzing systems for profile comparison have been examined, they cannot be used for the RLGS spot mapping system owing to the background characteristics of the RLGS profiles, unsatisfactory rates of correspondence, and inefficient correction of informative genetic data. We therefore developed a novel automatic image analysis system for RLGS spot mapping, using an original algorithm based on the binary image transferred from the original RLGS profile. This system was employed for identifying non-polymorphic and parental strain-specific polymorphic spots of the F1 mouse profile and yielded efficient initial screening of RLGS profiles.

Animals↗
PubMed1995

Particle size determination by automated microscopical imaging analysis with comparison to laser diffraction.

A rapid and precise microscopical analysis technique for the determination of particle size distribution has been developed. Particle size distribution was determined with a Carl Zeiss Axioplan microscope equipped with a computer-controlled image analysis system. Area and volume measurements were performed on a number of particles and plotted against Feret's diameter to yield a distribution histogram. This technique was then applied to several compounds of pharmaceutical interest, and the resulting histograms were compared with histograms determined with a laser diffraction instrument. The reproducibility of the microscopical determination was good and the agreement between the two determinations was dependent on the crystalline shape.

Crystallization↗