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PubMed2005

Differentiation of developmental and post-orthodontic white lesions using image analysis.

The aim of this study was to investigate differences in shape and size characteristics between developmental opacities and post-orthodontic white enamel lesions using computerized image analysis. Material, in the form of 35 mm slides, was obtained from the archive of photographic patient records in the orthodontic clinic at the Charles Clifford Dental Hospital. Images of 30 teeth with developmental white lesions and 30 teeth with post-orthodontic white lesions were selected using strict inclusion and exclusion criteria. The slides were converted to a digital format, coded, placed in a random order and analysed blindly using a computerized image analysis system by one clinician. After a 2 week interval, the images were recorded, placed in a new random order and the measurements repeated. The outcome measures were: area and luminance proportionality, and the shape of the perimeter line (expressed as the mathematical factor, roundness). Reproducibility was assessed by a paired samples t-test for systematic error and the intra-class correlation coefficient (ICC) for random error. Differences between groups were tested using the Mann-Whitney U-test for non-parametric data. Reproducibility was substantial for all measurements except for developmental white lesion roundness, which was moderate. There was a statistically significant difference between developmental white opacities and post-orthodontic white lesions for measurements of luminance intensity, proportionality (P = 0.002) and roundness (P = 0.001). Developmental white opacities had a higher luminance (i.e. were whiter) and the boundaries were more circular in shape than the post-orthodontic lesions. Roundness is a useful measure when distinguishing developmental and post-orthodontic demineralization.

Dental Enamel↗
PubMed1994

Measurement of inhibition zone diameter in disk susceptibility tests by computerized image analysis.

This paper presents an application of computerized image analysis in microbiology. This application permits the automatic detection and diameter measurement of inhibition zones in disk susceptibility tests. Each inhibition zone boundary was extracted according to an edge detection method based on the Student's t-test and a priori knowledge (geometry, densitometry). Evaluation of the method was performed by comparing the results from an image analyser and a trained observer. For this purpose, we used kappa statistics and obtained a close agreement (a kappa coefficient equal to 0.84) on a set of about 600 inhibition zones. The results encourage us to develop the method further to include the detection of antagonism and synergism.

Algorithms↗
PubMed1995

Superimposed Image Analysis System (SIAS) software: a new approach to sperm motility assessment.

OBJECTIVE: To apply Superimposed Image Analysis System (SIAS) software (Delta Sistemi, Rome, Italy) to the objective analysis of sperm motility. DESIGN: To test a new procedure for sperm motility assessment based on image superimposition. RESULTS: The system can superimpose six sequential frames onto a monitor producing a final image with a motion effect similar to the multiple exposure photography method, but bypassing the film processing stage. Viewing the final image of a complete series of six superimposed frames allows the evaluation of the percentage of motile spermatozoa and their kinetic characteristics. Compared with multiple exposure photography, SIAS has the following main advantages: [1] the procedure is quick; [2] projecting the first frame alone allows the easy evaluation of sperm concentration; and [3] the system allows quick and easy analysis and measurement of each sperm trajectory frame by frame, thus avoiding misleading interpretations because of crossing sperm trajectories, collisions, and overlapping of motile spermatoza with round cells or immotile spermatozoa. CONCLUSIONS: Superimposed image analysis is a new approach to sperm motility assessment. It seems to be useful particularly in selected situations, such as oligozoospermia or in cases of increased round cell concentration. In these situations, SIAS can even serve as a support or an alternative to the computer-aided sperm analysis system widely used for objective sperm analysis.

Humans↗
PubMed1993

Reevaluation by image analysis of the effects of fibroblasts, fibronectin or laminin upon colony formation in mouse lungs by B16 melanoma cells.

A recently described personal method based on image analysis of histological sections was used in order to quantify lung colony formation by B16 melanoma cells injected intravenously into the mouse. These tumor cells were preincubated in vitro either with fibronectin (FN), laminin (LN) or fibroblasts (FB), which are implicated in the process of invasion and metastasis. Thanks to this method, a more accurate analysis of lung colonies (section area and number) formed by tumor cells was realized. By image analysis, we show that when FB were mixed with B16 cells, a drastic increase of tumor sections number and area was induced. LN increased the tumor sections area, but not their number. No effect of FN on B16 cells was observed. LN and FN promoted tumor anchorage in the depth of the lungs while FB reduced the latter. These facts could explain the contradictory results obtained by simply counting macroscopically superficial lung colonies. When cultured in vitro, these B16 melanoma cells did not produce any type of IV collagenase, either alone or in the presence of LN or FN, but in cocultures (B16 with 3T3) and in fibroblasts cultures, this enzyme was present. This could explain, among other factors, why the rate of invasiveness exerted by B16 cells is higher when the latter are coinjected with FB.

3T3 Cells↗
PubMed1977

[Methods to prepare histological microautoradiographs for evaluation by automatic image analysis (author's transl)].

A prerequisite for automatic image analysis of histoautoradiographs is the arrangement of the silver grains within the same plane of focus. This can be obtained by semi thin sections of 1 micrometer in thickness. A sufficient contrast for the determination of the nuclear areas and the overlying silver grains at the same time can be reached by staining the preparations with Kernechtrot or Feulgen nucleal reaction. If a higher image contrast is desired sections measuring 2 micrometer or more in thickness may be subjected to the autoradiographic procedure without removing the resin.

Animals↗
PubMed2001

Identification of Trichoderma strains by image analysis of HPLC chromatograms.

Forty-four Trichoderma strains from water-damaged building materials or indoor dust were classified with chromatographic image analysis on full chromatographic matrices obtained by high performance liquid chromatography with UV detection of culture extracts. The classes were compared with morphological identification and rDNA sequence data, and for each class all strains were of the same identity. With all three techniques each strain--except one--was identified as the same species. These strains belonged to Trichoderma atroviride (nine strains), Trichoderma viride (three strains), Trichoderma harzianum (10 strains), Trichoderma citrinoviride (12 strains), and Trichoderma longibrachiatum (nine strains). The odd strain was identified as Trichoderma hamatum by morphology and rDNA sequencing, but not by image analysis as no reference strains of this species were included. It is concluded that the secondary metabolite profile contains sufficient information for classification and species identification.

Air Pollution, Indoor↗
PubMed2004

Anomalous pancreaticobiliary junction: image analysis and treatment principles.

BACKGROUND: Anomalous pancreaticobiliary junction is often associated with biliary tract carcinoma and acute pancreatitis. We assessed the value of image analysis in the diagnosis of patients with anomalous pancreaticobiliary junction (APBJ) and the principles for the treatment of APBJ. METHODS: Sixty-four patients with APBJ were subjected to ultrasound imaging, endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance cholangiopancreatography (MRCP) before surgery. The diagnostic accuracy of image analysis and their surgical outcomes were evaluated retrospectively. RESULTS: On ERCP and MRCP, the length of the common channel was calculated to be 15 mm or longer in all patients, and the angle of the junction was more than 75 degree in 49 (76.6%) of the 64 patients. Of the 64 patients, 28 were defined of pancreatic duct type (P-C) (28/64, 43.75%), 32 bile duct type (C-P) (32/64, 50%), and 4 common channel type (4/64, 6.25%). CONCLUSIONS: Patients with APBJ are often associated with biliary tract and pancreatic diseases, and early detection and correct surgical treatment could avoid serious complications. ERCP and MRCP are accurate in the diagnosis of APBJ.

Adolescent↗
PubMedDate not supplied

Structure analysis of the flagellar cap-filament complex by electron cryomicroscopy and single-particle image analysis.

The cap of the bacterial flagellum plays an essential role in the growth of the long helical filament by promoting the efficient self-assembly of flagellin transported to the distal end through the narrow central channel of the flagellum. The structure of the cap-filament complex was analyzed by electron cryomicroscopy and single-particle image analysis to understand how the cap stays attached while allowing the flagellin insertion between the cap and the filament end and also allowing the HAP proteins to pass through. In the images of the complex, the projection pattern of the helical subunit array in the filament portion occupied the major fraction but was variable depending on the azimuthal orientation of the filament; therefore the images showed a strong tendency to be misaligned. Various methods had to be newly developed to correctly align the images by overcoming this misalignment problem. The structure thus obtained clearly demonstrated the pentameric structure of the cap and how the cap operates. The new methods of analysis presented here would be generally applicable to cap structures of various filaments that play biologically important roles in cellular activities.

Bacteria↗
PubMed1992

DNA quantitation of Wilms' tumour (nephroblastoma) using flow cytometry and image analysis.

AIMS: To compare flow cytometry (FCM) with image analysis (IA) in the DNA quantitation of Wilms' tumour (WT) and to correlate data so obtained with recognised clinical and pathological prognostic parameters. METHODS: Thirty six patients with histologically proved WT diagnosed between 1980-89 were investigated. Fifteen patients had stage I disease, 10 stage II, six stage III, two stage IV and three stage V. Suspension of nuclei obtained by pepsin digestion of paraffin wax embedded tumour tissue was analysed using a FAC-Scan flow cytometer, and a CAS-100 image analyser. RESULTS: Tumours were concordant in most instances, however, IA identified aneuploidy in two tumour samples which were diploid by FCM. Aneuploidy was detected in 5/33 tumours with favourable histology and 3/3 with unfavourable histology. Three of 28 patients with Stage I, II and V disease and 5/8 patients with stage III and IV had aneuploid tumours. All patients with unfavourable histology died of disease. In the group with favourable histology, 4/5 patients with aneuploid tumours developed recurrent disease compared with 1/27 diploid tumours (p less than 0.0001). CONCLUSIONS: Ploidy may be a useful additional prognostic indicator in Wilms' tumour with favourable histology. Larger scale studies are needed to confirm the relation of ploidy to survival in early stage WT.

Child↗
PubMed2001

Tissue harmonic image analysis based on spatial covariance.

The van Cittert-Zernike theorem has been widely used to describe spatial covariance of the pressure field backscattered from a speckle object. Spatial covariance contains important information in the context of correlation-based correction of sound velocity inhomogeneities. Previous work was primarily based on spatial covariance analysis for linear imaging. In this paper, we extend the analysis to tissue harmonic imaging. Specifically, we investigate effects of the signal-to-noise ratio (SNR) and sound velocity inhomogeneities on spatial covariance. Results from tissue harmonic imaging are also compared with those from linear imaging. Both simulations and experiments are performed. At high SNRs, although both linear imaging and tissue harmonic imaging have spatial covariance functions close to theory, the spatial covariance of tissue harmonic imaging is consistently lower than that of linear imaging regardless of the presence of sound velocity inhomogeneities. At low SNRs, on the other hand, spatial covariance of tissue harmonic imaging is significantly affected. Because the tissue harmonic signal is much weaker than the linear counterpart, the low SNR reduces the accuracy of correlation-based estimation. It is concluded that the linear signal is more suitable for correlation-based correction of sound velocity inhomogeneities, despite the fact that tissue harmonic imaging generally has improved image quality over linear imaging.

Ultrasonography↗
PubMed2001

CMEIAS: A Computer-Aided System for the Image Analysis of Bacterial Morphotypes in Microbial Communities.

A major challenge in microbial ecology is to develop reliable and facile methods of computer-assisted microscopy that can analyze digital images of complex microbial communities at single cell resolution, and compute useful quantitative characteristics of their organization and structure without cultivation. Here we describe a computer-aided interactive system to analyze the high degree of morphological diversity in growing microbial communities revealed by phase-contrast microscopy. The system, called "CMEIAS" (Center for Microbial Ecology Image Analysis System) consists of several custom plug-ins for UTHSCSA ImageTool, a free downloadable image analysis program operating on a personal computer in a Windows NT environment. CMEIAS uses various measurement features and two object classifiers to extract size and shape measurements of segmented, digital images of microorganisms and classify them into their appropriate morphotype. The first object classifier uses a single measurement feature to analyze relatively simple communities containing only a few morphotypes (e.g., regular rods, cocci, filaments). A second new hierarchical tree classifier uses an optimized subset of multiple measurement features to analyze significantly more complex communities containing greater morphological diversity than ever before possible. This CMEIAS shape classifier automatically categorizes each cell into one of 11 predominant bacterial morphotypes, including cocci, spirals, curved rods, U-shaped rods, regular straight rods, unbranched filaments, ellipsoids, clubs, rods with extended prostheca, rudimentary branched rods, and branched filaments. The training and testing images for development and evaluation of the CMEIAS classifier were obtained from 1,937 phase-contrast grayscale digital images of various diverse communities. The CMEIAS shape classifier had an accuracy of 96.0% on a training set of 1,471 cells and 97.0% on a test set of 4,270 cells representing all 11 bacterial morphotype classes, indicating that accurate classification of rich morphological diversity in microbial communities is now possible. An interactive edit feature was added to address the main sources of error in automatic shape classification, enabling the operator to inspect the assigned morphotype of each bacterium based on visual recognition of its distinctive pseudocolor, reassign it to another morphotype class if necessary, and add up to five other morphotypes to the classification scheme. The shape classifier reports on the number and types of different morphotypes present and the abundance among each of them, thus providing the data needed to compute the morphological diversity within the microbial community. An example of how CMEIAS can augment the analysis of microbial community structure is illustrated by studies of morphological diversity as an indicator of dynamic ecological succession following a nutrient shift-up perturbation in two continuously fed, anaerobic bioreactors with morphologically distinct start communities. Various steps to minimize the limitations of computer-assisted microscopy to classify bacterial morphotypes using CMEIAS are described. In summary, CMEIAS is an accurate, robust, flexible semiautomatic computing tool that can significantly enhance the ability to quantitate bacterial morphotype diversity and should serve as a useful adjunct to the analysis of microbial community structure. This first version of CMEIAS will be released as free, downloadable plug-ins so it can provide wide application in studies of microbial ecology.

Journal Article↗
PubMed2005

Comparative characterization study of microporous carbons by HRTEM image analysis and gas adsorption.

The present work presents a useful comparison of micropore size distributions (MPSDs) obtained from gas adsorption and image analysis of high-resolution transmission electron micrographs. It is shown that the MPSD obtained for a chemical activated carbon is concordant with that obtained from CO2 adsorption. In addition, this technique has allowed us to obtain the MPSD of a carbon molecular sieve (CMS) prepared in our laboratory by a copyrolysis process, which could only be characterized by CO2 adsorption at 273 K (not by N2 adsorption at 77 K due to diffusional problems). The MPSD obtained by high-resolution transmission electron microscopy (HRTEM) for the CMS is wider than that obtained by CO2 adsorption, suggesting that HRTEM is detecting the closed porosity existing in this sample, which is not accessible to gas adsorption. The existence of closed porosity in the CMS is explained considering the preparation method used. Thus, HRTEM combined with image analysis seems to be useful for structural analysis of narrow micropores including closed porosity.

Journal Article↗
PubMed1987

Morphometric markers for the evaluation of preneoplastic lesions in the lung. Diagnostic evaluation by high-resolution image analysis of atypical cells in sputum specimens.

A review is presented of the Baylor College of Medicine/NASA/Lyndon Johnson Space Center high-resolution image analysis system for the detection of preneoplastic lesions of the lung in sputum specimens. For each specimen, 200 cells are graded as to their Atypia Status Index (ASI), a numerical classification based on a weighted composite of morphometric markers identified in the digitized images. The ASI values, which place individual cells within categories ranging from squamous metaplastic to carcinomatous, form the basis of the Cell Atypia Profile (CAP), which reflects the overall status of the patient's bronchial epithelium and can be used to diagnose and monitor epithelial atypias. Initial studies have shown the ASI and CAP to be accurate indices, whose application in the studies of sputum of individuals at high risk for the development of lung cancer (cigarette smokers over 45 years of age and industrially exposed workers) could lead to the early detection of preneoplastic lung lesions and to effective early clinical intervention, including the cessation of smoking or the application of beta-carotone or retinoids, which reportedly arrest the progression of bronchial epithelial atypias. Computer-assisted cell image analysis of morphometric markers in cells in sputum specimens appears to be uniquely applicable for surveillance of individuals at risk for carcinoma of the lung.

Bronchi↗
PubMed1987

Application of digital image analysis in cataract retroillumination photography.

The Stuttgart digital image analysis system for Scheimpflug photography can be applied without additional extension for pattern recording and densitometric measurements in retroillumination photographic techniques. A preliminary investigation with serial photographs in human cataract showed a large variation in the measured results. Standardisation of photographs taken by the retroillumination technique is not yet possible. For this reason, application of the retroillumination technique is not suitable at this time for clinical longitudinal studies.

Cataract↗
PubMed1992

[An image analysis system for optic disc in glaucoma].

An image analysis system for glaucomatous optic disc was developed. The key for optic disc measurement was to trace accurately the boundaries of the optic cup and disc. The 2-dimension measurement modality adopted was the heuristic boundary tracing method, and the 3-dimension measurement was performed by observation of the photographs, arbitrary selection of points, and automatic plotting and calculation. In order to measure accurately the optic disc in glaucoma follow-up, the authors made use of the cross correlation line by line scanning method, after proper correction of the photographs, to detect any positional shift in two photographs. By clinical verification, the 95% confidence criterion of normal optic cup boundary shifting was 1.7 pixels. The optic disc diameter of the disc images was over 200 pixels, and any shift over 2 pixels (1%) would have clinical significance, which was a high degree of precision.

Glaucoma↗
PubMed2000

Predictive value of DNA cytometry in CIN 1 and 2. Image analysis of 193 cases.

OBJECTIVE: To investigate DNA image cytometry for predicting the prognosis of cervical intraepithelial neoplasia (CIN). STUDY DESIGN: Smears from 151 women affected by CIN 1 or 2 on cytology with minimal follow-up of three years were included. Sixty-seven showed progression, with histologically confirmed carcinoma in situ or invasive cancer. Eighty-four cases showed regression of the disease, which was cytologically, histologically and colposcopically confirmed. Papanicolaou-stained smears were destained, and the Feulgen reaction was performed with consecutive image DNA cytometry of suspicious cells using an image analysis system (Cires, Zeiss, Germany). The DNA index of the greatest stemline and the number of single aneuploid cells, using 9c exceeding events, were computed. RESULTS: In the group with progression, an aneuploid DNA stemline was found in 25 smears (26.9%). In 64 cases (66.7%) more than one aneuploid event was detected. The total number of aneuploid cases in this group was 76 (81%). In the group without progression, the number of aneuploid stemlines was 2 (2%). Single aneuploid cells could be found in five cases (5%). The overall number of aneuploid cases in that group was five. The sensitivity was 74.3%, positive predictive value 85.2% and negative predictive value 77%. CONCLUSION: Aneuploidy is a marker for prospective malignancy in cervical Papanicolaou smears. DNA image cytometry, as an additional method, can be used to predict outcome in patients with CIN 1 and 2 of the cervix. DNA cytometry is not a screening method but can add further information for a treatment decision in doubtful cases.

Adult↗
PubMed2002

[A digital tongue image analysis instrument for Traditional Chinese Medicine].

A digital tongue image analysis instrument (TIAI) based on computer for Traditional Chinese Medicine is introduced. Some of the key techniques, including the image acquiring condition and method, the evaluation of tongue characters, and the management of tongue image data, are discussed as well. TIAI can provide a non-invasive, quantitative, and objective analysis approach and enhance the theory level and practical ability of the Traditional Chinese tongue diagnosis.

Algorithms↗
PubMed1993

Analysis of lymphocyte aggregation using digital image analysis.

We present the development and testing of a novel assay of lymphocyte adhesion based on time-resolved morphological measurements of intercellular aggregation. Homotypic lymphocyte aggregation is induced according to various protocols and monitored for several hours using video microscopy and time-lapse recording. Digital images of the aggregating cell population are acquired and analyzed to obtain the size distribution and the shape of cell aggregates. By following the temporal evolution of the size distribution of aggregates, the rates of aggregation events can be accurately quantified and compared. In addition, an analysis of the two- and three-dimensional structures of the aggregates using appropriately defined shape factors allows comparisons of mechanical binding strengths and cytoskeletal activity. To demonstrate the capabilities of the assay, we present results from a series of aggregation experiments with Jurkat cells treated with 33B6, 19H8, IC9, and 20E4 monoclonal antibodies. These monoclonal antibodies bind to various epitopes of known adhesion molecules and induce aggregation phenomena that proceed at different rates. Our results show that the assay has small repeatability error and is sensitive enough to compare aggregation events induced through distinct molecular epitopes. Used in conjunction with current biochemical detection assays and adhesion pathway modulation experiments, the developed assay will facilitate the study of cellular adhesion and aggregation mechanisms.

Antibodies, Monoclonal↗