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PubMed1991

3-D image analysis system and megakaryocyte quantitation.

A quasi-automatic computer image analysis system has been developed for 3-D reconstruction of stained serial sections and implemented on an IBAS system. Some new automatic image analysis techniques have been designed and incorporated into the system. For image segmentation, a transition region determination based thresholding method is introduced. Neither histogram calculation nor empirical parameters are needed in the automatic threshold selection. A two step 3-D reconstruction procedure--symbolic and pictorial reconstructions--is designed to improve the flexibility and the computational capability of the system. The global level registration and local level registration are separated. The former consists of establishing the relationship among a large numbers of profile pairs dispersed in adjacent sections. A pattern matching method based on pattern recognition principles is devised to exploit the information about the statistical character of mismatch caused by deformation of sections and about the relationship of nearby objects. For the latter, an equivalent elliptical approximation method based on the physical theory of the rotation of rigid bodies is proposed. The system has been used for 3-D reconstruction and quantitation of megakaryocytes in human bone marrow tissue. Features about individual 3-D megakaryocyte cell and the spatial distribution of megakaryocytes are determined. The latter is a new contribution to megakaryocyte quantitation and is not possible by using conventional stereologic techniques. These experimental results have demonstrated the ability of the system to perform quantitative analysis.

Humans↗

PubMed1992

The use of image analysis to evaluate the development of uterine and oviduct epithelial cells during in vitro culture. A potential quality assurance procedure for in vitro laboratories.

The objective of this study was to establish selection criteria for morphologic assessment of cell quality using a computer image-analysis system. Uterine and oviduct epithelial cells were isolated from the reproductive tracts of cyclic cows using a trypsin solution. Harvested cells were cultured in Tissue Culture Medium-199 with 10% fetal bovine serum and maintained at 37 degrees C with 5% carbon dioxide in air. Subcultures of different confluent monolayers were established using a weak trypsin solution. Morphologic assessment of cell integrity and viability were made visually, with electron microscopy and image analysis. After morphologic assessment, cells were assigned quality scores. Evaluations were conducted on cells during primary culture and following the first and third subpassages. Image-analysis evaluation was conducted on cells using a silicon-intensified target camera and computer-based software. Gray-level density was determined on cells from each flask. There was no difference (P greater than .05) between sample replicates, indicating repeatable measurements were obtained with the image-analysis system. In addition, there was no significant difference in parameters measured between uterine and oviduct cells; therefore, data from both cell types were combined for further statistical comparisons. Gray-level density values for combined uterine and oviduct cells during primary culture and following the first and third subpassages were as follows: 139.7, 154.5, and 173.3, respectively. There was an increase (P less than .05) in gray-level density values with each subpassage of the cell populations. Furthermore, gray level was influenced (P less than .01) by cell quality for combined uterine and oviduct cell populations. These results indicate that epithelial cell quality during in vitro culture may be effectively determined using image analysis. This approach should not be overlooked in establishing quality control measures for uterine and oviduct cells before mammalian embryos are cocultured in vitro.

Animals↗

PubMed1995

Topodermatographic image analysis for melanoma screening and the quantitative assessment of tumor dimension parameters of the skin.

BACKGROUND: The clinical need to identify and evaluate changes of cutaneous lesions in melanoma screening or follow-up of patients with cancer is of paramount importance. Because skin-lesion changes may be small and numerous, clinical assessment alone does not meet the requirements of quantitative assessment. Using the computer as a diagnostic tool for the image analysis of sequentially captured skin surface images has resulted in the technical problem of insufficient registration reproducibility. This paper describes the technical logistics, setup procedure, and clinical evaluation of the novel technique termed "topodermatography," which performs the quantitative videographic image analysis of skin-lesion changes over time. METHODS: Digitized measurements of skin-surface image parameters were performed using a high-speed processor with an onboard coprocessor, a high-resolution video camera, specifically designed image processing software, and a position framework for the adjustment of the patient's standing position. The topodermatographic image analysis was performed on 109 consecutive patients who were at risk for melanoma (N = 98), had lesions from Kaposi's sarcoma (N = 4), had metastatic skin deposits from melanoma (N = 3), and had breast cancer (N = 4). RESULTS: Skin lesion changes over time could be identified reliably within a few millimeters of diametric enlargement. In this series, a 0.51% early melanoma detection rate was assessed in 19 of 98 patients followed for 12 months. By monitoring manifest neoplastic skin lesions, tumor growth kinetics were analyzed quantitatively to determine the total area of skin involvement, thus facilitating precise response assessment. CONCLUSIONS: Topodermatographic image analysis helps to optimize screening and follow-up procedures for patients with melanoma and populations at risk for melanoma. In addition, metastatic tumor lesions on the skin can be monitored dynamically, facilitating the accurate evaluation of the impact of systemic therapy on multiple skin deposits from melanoma and nonmelanoma cancers.

Adolescent↗

PubMed1990

[Image analysis study of squamous epithelial cells in cytological smears of the uterine cervix].

The automated image analysis is a method, which may model essential effects of the cytologist's perception, combined with an increase of objectivity. We studied 9136 epithelial cells from 105 suspension smears of the cervix by means of image analysis. The results show that the process of maturation of squamous cells can be represented by image analysis parameters. Such a model enables an opposition of processes of differentiation and dedifferentiation. Furthermore subvisual changes in visual inconspicuous intermediate cells can be proved, too which appear in different degree correlated with the grade of dedifferentiation. At present a study is designed to investigate cases without any atypical cells, but having been classified as "positive cases" by the evaluation of intermediate cells in a long term follow-up.

Carcinoma, Squamous Cell↗

PubMed2000

Image analysis of insulation mineral fibres.

We present two methods for measuring the diameter and length of man-made vitreous fibres based on the automated image analysis of scanning electron microscopy images. The fibres we want to measure are used in materials such as glass wool, which in turn are used for thermal and acoustic insulation. The measurement of the diameters and lengths of these fibres is used by the glass wool industry for quality control purposes. To obtain reliable quality estimators, the measurement of several hundred images is necessary. These measurements are usually obtained manually by operators. Manual measurements, although reliable when performed by skilled operators, are slow due to the need for the operators to rest often to retain their ability to spot faint fibres on noisy backgrounds. Moreover, the task of measuring thousands of fibres every day, even with the help of semi-automated image analysis systems, is dull and repetitive. The need for an automated procedure which could replace manual measurements is quite real. For each of the two methods that we propose to accomplish this task, we present the sample preparation, the microscope setting and the image analysis algorithms used for the segmentation of the fibres and for their measurement. We also show how a statistical analysis of the results can alleviate most measurement biases, and how we can estimate the true distribution of fibre lengths by diameter class by measuring only the lengths of the fibres visible in the field of view.

Journal Article↗

PubMed1995

Ploidy analysis on Wilms' tumour touch imprints using ethidium bromide and automated image analysis integrated confocal laser scanning microscopy.

Although image analysis (IA) is increasingly being used to quantitate nuclear DNA, comparative data between fluorescence methods of IA and flow cytometry (FCM) is limited. In this study fluorescence IA was compared with FCM data in a series of Wilms' tumour touch preparations. Airdried touch imprints that had previously been Giemsa stained were restained with ethidium bromide. Confocal fluorescence images were obtained with a confocal laser scanning microscope and assessed by a fully automated IA package. Data was collected from 400 nuclei per imprint. The resulting DNA histograms were analysed and ploidy status and DNA indices determined using standard criteria. Results were compared with those derived from FCM analysis of nuclear suspensions. Ten of twelve tumours were concordant by both techniques. However in two cases assessed as diploid by FCM, IA identified aneuploidy. Excellent correlation between DNA indices as assessed by both techniques was observed (r = 0.987). In the three cases for which both unstained and Giemsa stained touch imprints were available for IA, the histogram configurations did not differ significantly. Fluorescence IA is an accurate and sensitive technique for DNA quantitation, which appears at least comparable to FCM assessment and which has a number of important advantages.

Child, Preschool↗

PubMed2001

DNA image analysis combined with routine cytology improves diagnostic sensitivity of common bile duct brushing.

BACKGROUND: Cytologic evaluation of common bile duct brushings has a low sensitivity for diagnosing malignancy because of scant cellularity, poor cellular preservation, or sampling errors occur. The aim of this study was to evaluate whether cytology combined with image analysis improves the diagnostic accuracy of bile duct brushing in comparison with cytology alone. METHODS: Forty-nine specimens of bile duct brushings obtained from 45 patients during endoscopic retrograde cholangiopancreatography were evaluated using cytology and image analysis. Specimens were classified as negative, atypical, suspicious, or malignant by using cytologic evaluation. DNA histograms were classified as diploid (D), broad diploid (BD), aneuploid (A), or tetraploid (T). Degree of hyperploidy (DH), representing cells with a DNA content > 5C was evaluated using a cutoff value of > or = 1%. Final diagnosis of cancer was based on tissue specimens that were obtained by fine-needle aspiration or surgical biopsy and clinical fol- low-up. RESULTS: Thirty-four patients ultimately proved to have a malignancy. Cytology revealed 19 negative cases, 15 atypical cases, 9 suspicious cases, and 6 malignant cases. Together, suspicious and malignant cytology cases yielded a sensitivity of 44% and a specificity of 100% for a cytologic diagnosis of cancer. The DNA histogram pattern was D in 24 cases, BD in 9 cases, and A in 16 cases. BD and A patterns were significantly associated with malignancy (P < 0.001). A DH > or = 1% was noted in 22 cases. DH alone had a sensitivity of 62% and a specificity of 91% and was significantly associated with malignancy (P < 0.004). Atypical cytology alone had a false-negative rate of 29%, but in combination with a DH > or = 1%, the false-negative rate decreased to 7%. Additionally, when the authors combined atypical, suspicious, and malignant cytology with a DH > or = 1%, the diagnostic sensitivity increased to 88%, but the specificity decreased to 73%. CONCLUSIONS: Combined cytology and image analysis of bile duct brushing increased diagnostic sensitivity compared with cytology alone. The findings suggest that image analysis may help select patients having atypical cytology who should undergo a more rigorous evaluation for malignancy. A larger prospective study of the usefulness of combined cytology and image analysis of bile duct brushing is warranted.

Adult↗

PubMed1997

Evaluation of manual and image analysis quantification of DNA damage in the alkaline comet assay.

The alkaline comet assay or single cell microgel electrophoresis assay is a sensitive method of detecting DNA strand breaks and alkali labile sites in individual cells. The results of this assay can be analysed by different methods. In this study we compared analyses of the same slides by a manual method and by image analysis, post-treatment of clone 707 Friend erythroleukaemia cells with H2O2. The parameters which were found to be particularly useful were comet area and comet length (measured manually) and percentage tail DNA, tail moment, tail length and tail length/head radius (L/H), measured using image analysis. The manual method for comet analysis presented in this paper would appear to provide good and reliable comet data. However, the image analysis comet system described offers an alternative analysis method which avoids the need for photomicrographs and tedious manual analysis. The image analysis parameters: % tail DNA, tail moment, tail length and L/H give good consistent results and for large-scale analysis it will, therefore, conceivably be the method of choice.

Animals↗

PubMed2006

Computer image analysis of ultrasound biomicroscopy of primate accommodation.

PURPOSE: To assess and correct images of the eye for movements that can confound the evaluation of the presence, direction, and magnitude of intraocular movement of the crystalline lens equator during centrally induced ciliary muscle contraction (accommodation). METHOD: Ultrasound biomicroscopic (UBM) video images of a cynomologus monkey crystalline lens were obtained from an independent source. The images, prior to, during, and following electrical stimulation of the Edinger-Westphal (EW) nucleus were compared for evidence of movement of the crystalline lens equator. Extraocular eye movements were assessed by use of objective computer imaging analysis techniques. RESULTS: Extraocular eye movements were identified and reduced by using objective computer imaging analysis techniques to register and realign the corneal images. Highly significant corrections are required to effect corneal realignment. Analysis of paired and registered images from this data source indicates that any movements of the primate lens equator are not detectable when maximum accommodation was induced by EW stimulation. CONCLUSION: The displacement of the edge of the primate crystalline lens equator during electrically induced contraction of the ciliary muscle is a small displacement phenomenon, only analysable after confounding extraocular movements are removed from the compared images.

Accommodation, Ocular↗

PubMed1991

Immunohistochemical progesterone receptor assay. Measurement by image analysis.

To determine the efficiency of image analysis in immunohistochemical progesterone receptor (PgR) measurement, 94 primary breast carcinoma tissue samples were evaluated for PgR by biochemical dextran-coated charcoal assay (DCC) and an immunohistochemical method. Frozen sections immunostained for PgR with a monoclonal antibody (Abbott PgR-ICA, Chicago, IL) and the peroxidase-antiperoxidase technique were scored semiquantitatively histologic score by microscopy and quantitatively (percentage nuclear area immunopositivity [PNA] using the CAS 200 image analyzer (Cell Analysis Systems, Elmhurst, IL). There was a positive correlation between dextran-coated charcoal assay and both histologic score (r = 0.82) and PNA (r = 0.69). Selected cutoff points of 60 histologic score and 6.5% PNA based on sensitivity/specificity calculations yielded a predictive value of a negative test of 73% and 80%, respectively, and a positive predictive value of 100% for both; ranges of fmol/mg protein PgR correspond to ranges of histologic score and PNA. The use of an image analyzer to measure PNA in PgR-immunostained sections is a viable alternative to dextran-coated charcoal assay, especially when insufficient fresh tissue is available.

Biochemistry↗

PubMed1996

Deformable models in medical image analysis: a survey.

This article surveys deformable models, a promising and vigorously researched computer-assisted medical image analysis technique. Among model-based techniques, deformable models offer a unique and powerful approach to image analysis that combines geometry, physics and approximation theory. They have proven to be effective in segmenting, matching and tracking anatomic structures by exploiting (bottom-up) constraints derived from the image data together with (top-down) a priori knowledge about the location, size and shape of these structures. Deformable models are capable of accommodating the significant variability of biological structures over time and across different individuals. Furthermore, they support highly intuitive interaction mechanisms that, when necessary, allow medical scientists and practitioners to bring their expertise to bear on the model-based image interpretation task. This article reviews the rapidly expanding body of work on the development and application of deformable models to problems of fundamental importance in medical image analysis, including segmentation, shape representation, matching and motion tracking.

Animals↗

PubMed2005

Computerized image analysis for quantitative neuronal phenotyping in zebrafish.

An integrated microscope image analysis pipeline is developed for automatic analysis and quantification of phenotypes in zebrafish with altered expression of Alzheimer's disease (AD)-linked genes. We hypothesize that a slight impairment of neuronal integrity in a large number of zebrafish carrying the mutant genotype can be detected through the computerized image analysis method. Key functionalities of our zebrafish image processing pipeline include quantification of neuron loss in zebrafish embryos due to knockdown of AD-linked genes, automatic detection of defective somites, and quantitative measurement of gene expression levels in zebrafish with altered expression of AD-linked genes or treatment with a chemical compound. These quantitative measurements enable the archival of analyzed results and relevant meta-data. The structured database is organized for statistical analysis and data modeling to better understand neuronal integrity and phenotypic changes of zebrafish under different perturbations. Our results show that the computerized analysis is comparable to manual counting with equivalent accuracy and improved efficacy and consistency. Development of such an automated data analysis pipeline represents a significant step forward to achieve accurate and reproducible quantification of neuronal phenotypes in large scale or high-throughput zebrafish imaging studies.

Animals↗

PubMed1997

Reproducibility of digital image analysis for measuring corneal haze after myopic photorefractive keratectomy.

PURPOSE: To evaluate the usefulness of digital image analysis for quantifying corneal haze by determining the reproducibility of its measurements at the corneal plane. METHODS: In a prospective study, 20 randomly selected eyes that had undergone myopic photorefractive keratectomy were photographed focusing the slit beam on their anterior corneal surface. Each photograph was examined using computer image analysis techniques that detect the edge of the reticular pattern of the image. Quantification of the difference between two areas, treated and adjacent untreated cornea, each containing 3,750 pixels with a resolution of 256 gray levels, was performed. Intra-analyzer variation was determined by evaluating the photographs obtained by two analyzers under standard conditions on four separate visits. Interanalyzer variation was calculated using one measurement and the mean of the four measurements. RESULTS: The pooled standard deviation of the measurements for the analyzers was 0.63 and 0.62 gray levels (coefficient of variation, 4.1% and 3.3%). An association between less severe haze measurements and higher reproducibility scores was found (r = .42; P = .007). The mean interanalyzer variation was smaller for the average of four measurements, 0.55 +/- 0.37 gray levels, than for one measurement, 0.94 +/- 0.73 gray levels (P = .014). CONCLUSIONS: Good reproducibility for haze measurements by digital image analysis of the differences between the treated and adjacent untreated corneal areas was obtained. When the average of four measurements was used instead of a single measurement, interanalyzer reproducibility increased significantly. This new technique may be used to quantify and analyze corneal haze after myopic photorefractive keratectomy.

Adult↗

PubMed1991

An image analysis method for assessment of prognostic risk in prostate cancer: a pilot study.

Fully automated computerized image analysis at medium resolution (1 micron per pixel space) was applied in a study of 17 patients with stage D1 prostate cancer. For this pilot study, patients were selected on the basis of very good or very poor outcome. This selection was made in the hope of identifying morphometric features that are useful in prognostic assessment. Nine patients with good outcome were alive after 7 or more years of follow-up and eight patients with poor prognosis were dead of disease in less than 3 years. All patients were treated with 125I seed implantation to the prostate and pelvic lymph node dissection. Hormone therapy was not administered until the time of distant failure. Routine hematoxylin and eosin tissue sections of lymph nodal tissue bearing metastatic neoplasm were used for this analysis. A minimum of eight scenes per case was analysed. Of 50 measured parameters on each cluster, five (gray level distribution, number of cell clusters per scene, bending energy, average cluster area and cluster polarity) were useful to distinguish patients with good outcome from those with a poor outcome. Thirteen of the 17 patients were correctly classified by image analysis (P = 0.044, Fischer's exact test). By comparison, flow cytometry of the identical tissue samples correctly classified 14 of 17 patients (diploid, good outcome; aneuploid, poor outcome; P = 0.009). Only one patient was incorrectly classified by both image analysis and flow cytometry, implying a complementary prognostic role for the two methods. The encouraging result, successful identification of useful morphometric features, justifies a larger study of unselected patients.

DNA↗

PubMed1999

Image analysis of p53 and cyclin D1 expression in premalignant lesions of the oral mucosa.

OBJECTIVE: The expression of p53 and cyclin D1 proteins was analyzed by image analysis in oral premalignant lesions and normal oral mucosa. STUDY DESIGN: Punch biopsies from the normal oral mucosa were obtained from 20 normal donors and 41 patients with oral dysplastic leukoplakias. After controlled formaldehyde fixation and paraffin embedding, immunohistochemistry was used to detect cyclin D1 and p53. Image analysis was performed using stain intensity levels established by determining color thresholds (nuclear score) in the basal and parabasal layers. RESULTS: Analysis of sections showed a similar pattern: only two normal donors had a few intensely positive p53 cells in the basal layer of the floor of the mouth and the tongue epithelia. Similarly, only three donors had intensely positive cyclin D1 cells in the normal epithelia of the same sites. Most cells fell in the range of negative or marginal stain (lower quartiles or terciles of nuclear score). These data on normal mucosa were compared with low grade oral leukoplakias (LGD) with mild to moderate dysplasia and with high grade leukoplakias (HGD) with severe dysplasia. Both markers were differentially expressed in precursor lesions versus normal epithelia. Statistical analysis of our data shows that the intensity of the immunohistochemical stain, as reflected in the nuclear scores of p53, is a reliable parameter that can differentiate between LGD and HGD of the oral mucosa. This was especially true when higher nuclear scores were compared. In contrast, low nuclear scores are more effective in differentiating normal epithelia from dysplastic epithelia. Although cyclin D1 immunohistochemistry does not stain as intensely as p53 stain, similar conclusions can be derived from those data. CONCLUSION: Image analysis of these two markers proved useful in distinguishing normal oral epithelia from low grade and high grade leukoplakias. With further developments in this field it is hoped that image analysis procedures could be used in different types of studies in which variations of protein expression in tissue sections could have prognostic implications or could be useful to determine subtle effects of curative or preventive treatment.

Adolescent↗

PubMed2002

Analysis of trotter gait on the track by accelerometry and image analysis.

The aim of this study was to describe the correlation between the phases of the limb cycle of trotters on the track and specific points on the acceleration curves obtained from a new gait analysis system. We compared kinematic data obtained by video image analysis and 3-dimensional acceleration recordings made on 3 French trotters in training. They trotted on a race track at speeds of 8.33, 10 and 11.66 m/s, with a final stretch at maximum speed. Their locomotion was recorded with a synchronised video camera at a frame frequency of 200 Hz and with the Equimétrix gait analysis system. The gait variables were calculated using 3-dimension acceleration data recorded at the sternum (dorso-ventral, longitudinal and lateral axes) at a sampling rate of 100 Hz. Three phases of the stride were clearly identified on the dorsoventral acceleration signal: hoof-landing, midstance phase and toe-off. Braking and propulsion phases were identified on the corresponding longitudinal acceleration signal. The weight-bearing diagonal was identified by observing the lateral signal. The stride temporal variables (stride, stance, braking and propulsion durations for both diagonals), measured by video analysis and by acceleration signal analysis, were not significantly different (P>0.05). The identification of specific points on the acceleration pattern allowed an accurate temporal analysis of the stride. Potential applications could be the determination of locomotor factors related to racing performance or assessment of locomotor disorders at high speed.

Acceleration↗

PubMed2006

Detection of human chromosomal abnormalities using a new technique combining 4',6-diamidino-2-phenyl-indole staining and image analysis.

Chromosomal abnormalities are associated with a variety of diseases. We have developed a new technique for detecting chromosomal abnormalities, and the technique combines conventional 4',6-diamidino-2-phenyl-indole staining (DAPI) with image analysis. The image analysis consists of two simple steps: deconvolution and three-dimensional reconstruction. The technique has been reported for analyzing plant chromosomes but has not been applied to analyze human chromosomes yet. To test the technique, we analyzed five translocations: 46,XX,t(3;21)(12;18), 46,XX,t(11;22), 46,XY,t(7;22), 46,XY,t(11;18), and 46,XY,t(3;7). The results showed that the karyotype of the 46,XX,t(3;21)(12;18) was 46,XX,t(3;21)(q11.1;p13),t(12;18) (q21.2;q23), and the karyotypes of the 46,XX,t(11;22), 46,XY,t(7;22), 46,XY,t(11;18), and 46,XY,t(3;7) were 46,XX,t(11;22)(q23;q12.1); 46,XY,t(7;22)(q32;q13.2); 46,XY,t(11;18)(q13.3;q23), and 46,XY,t(3;7)(q22.1;p13), respectively. The identity of derivative chromosomes involved in the translocations was verified by chromosome painting as well as FISH analyses with centromere probes. The new technique has two advantages: the procedure is simple and convenient, and the results are accurate. The technique has the potential to be used in cytogenetic studies and clinical diagnosis of human diseases in the future.

Adult↗

PubMed1992

Prognostic significance of DNA measurement determined by image analysis in human breast carcinoma.

The nuclear DNA of human breast carcinoma cells was studied by image analysis using archival paraffin-blocked tissues from two groups of patients with breast cancers. One group had survived greater than 10 years (N = 20) and the other less than 3 years (N = 26) after the initial diagnosis. Cellular preparations were made from pepsin-digested deparaffinated sections. The nuclear DNA was stained with Feulgen stain and measured by a computerized image analysis system. The data show that in addition to nodal status the pattern of DNA histograms obtained from image analysis can provide powerful prognostic information in breast carcinoma. The prognostic value of DNA histogram patterns may be independent of nodal status.

Breast↗