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PubMed2004

Value of the clinical history for different users of dermoscopy compared with results of digital image analysis.

BACKGROUND: The clinical history of a given pigmented lesion could influence the therapeutic decision. Teledermatology and automated image analysis also hold great potential for revolutionizing dermatology services. AIM: The aim of this retrospective study was to evaluate the diagnostic accuracy of users with different experiences in dermoscopy with and without information about patients and their history compared with classification by an automated analysing system. SETTING: One hundred and fifty-seven dermoscopic images of pigmented lesions, taken and proved by histopathology at the Pigmented Lesions Clinic of the Department of Dermatology of the University Tuebingen, Germany, were included. METHODS: All images were viewed by three investigators with different experience: excellent (A), average (B) and beginner (C). In the first dermoscopic classification, no information was available. After 3 months the same images were once more classified by the three investigators, now with the information about the patients and their history. The melanocytic lesions were tested by the Tuebinger Mole Analyser. RESULTS: For user A the sensitivity, specificity and diagnostic accuracy revealed no improvement on including the history (81.3% to 84.4%, 94.6% to 92.3% and 92.0% to 90.7%), whereas user B clearly improved his results (75.0% to 87.5%, 76.9% to 88.5% and 76.5% to 88.3%). No change in the sensitivity was seen by user C (84.4%), but there was a clear improvement in the specificity (69.2% to 87.7%) and diagnostic accuracy (72.2% to 87.0%). Using the computer algorithm, a sensitivity of 100%, a specificity of 76.9% and a diagnostic accuracy of 81.9% were achieved. CONCLUSIONS: The study revealed results relevant to the use of dermoscopy: (1) continuing dermoscopic education influences the diagnostic accuracy; (2) the history is helpful for averaged users and beginners in dermoscopy; (3) digital image analysis has the highest sensitivity, but a lower specificity compared to the clinicians; and (4) digital dermoscopy could be used for store-and-forward systems in teledermoscopy.

Adolescent↗
PubMed1989

Characterization of the morphological properties of welding fume particles by transmission electron microscopy and digital image analysis.

The morphological characteristics of welding fume particles have been determined using transmission electron microscopy (TEM) and automatic image analysis (AIA). Two personal samples and one background sample were collected using a new, easy to handle sampling method, during tungsten inert gas (TIG) and manual metal arc (MMA) welding on Inconel in the same shop. The collection method gave samples which were suitable for TEM and AIA. Electron micrographs were taken in a transmission electron microscope and further analyzed using an image analysis unit. Aggregates composed of many individual particles were analyzed both for the parameters of the aggregate and for the parameters of the individual particles by using an algorithm based on a grain boundary reconstruction technique. The morphological parameters allowed the welding fume's particulate matter to be divided into three types - here called small, medium, and large - with a somewhat unclear distinction between medium and large. Medium and large particles occur either as individual particles or as clusters of approximately spherical particles with average diameters of 0.07 and 0.15 microm, respectively. Small particles occur almost exclusively as long chains or lace-like structures of aggregates of particles, often in the range of 5-10 microm. The aggregates have an average projected area of 2.6 x 10-3 microm2 and are composed of several hundred individual particles.

Air Pollutants↗
PubMed2003

Preparation of macroporous biodegradable poly(L-lactide-co-epsilon-caprolactone) foams and characterization by mercury intrusion porosimetry, image analysis, and impedance spectroscopy.

Two poly(L-lactide-co-epsilon-caprolactone) random copolymers containing 5 and 40 mol % of epsilon-CL, namely P(LA-co-CL(5)) and P(LA-co-CL(40)), respectively, have been made macroporous by freeze-drying solutions in dimethylcarbonate. Most of the freeze-dried foams, prepared by varying polymer concentration and cooling rate, exhibited two main pore populations: (1). longitudinally oriented tube-like macropores with diameters >or=100 microm, and (2). interconnected micropores (10-100 microm). Pore characteristics, including macropore density, mean diameter, and interdistance, as well as micropore density, area, and shape, were determined by image analysis of scanning electron micrographs in order to study the influence of processing and formulation parameters on foam structure and properties. The pore orientation and the 3-D texture also were studied by image analysis and impedance spectroscopy. In the case of the P(LA-co-CL(5)), the macropore diameter increased with the cooling rate while the micropore diameter decreased. The micropores also became more circular when the cooling rate was increased. The pore size and morphology of the P(LA-co-CL(40)) were quite unchanged by varying the cooling rate. All the other conditions being the same, the P(LA-co-CL(5)) foams were better organized than the P(LA-co-CL(40)) foams, and pore orientation was improved at the higher cooling rate. Pore size and morphology also can be controlled by changing the polymer concentration (Cp), as we showed by studying P(LA-co-CL(5)) foams prepared by freeze-drying solutions in the 1-10 w/v % Cp range. Macropore density, average diameter, and interdistance of P(LA-co-CL(5)) foams increased with Cp, but the micropore characteristics remained almost unchanged no matter the Cp. The reliability of the characterization methods has been discussed, with special attention to mercury intrusion porosimetry, which is used primarily for measurement of pore volume and pore size distribution. However, this technique is reported here as a destructive and unreliable method for the characterization of fragile P(LA-co-CL(40)) foams. This study shows that image analysis and impedance spectroscopy can give reliable information relative to the pore morphology and anisotropy of freeze-dried foams.

Biocompatible Materials↗
PubMed1992

Short fixation-shock freezing and freeze-drying versus chemical fixation and dehydration: computer assisted image analysis of morphological variables and immunogold labeling density on pituitary secretory granules.

We have performed a computer assisted image analysis evaluation of the effects of two preparation protocols on morphological variables and immunolabeling density of secretory granules using rat adenohypophysis as a model. Glutaraldehyde (GA) fixation for 2 hr and chemical dehydration was compared with short GA fixation (15 min) followed by cryofixation and freeze-drying (CF-FD). The 2 hr GA fixed specimens showed spherical nuclei and secretory granules regardless of their size, contrasting with the more irregularly shaped nuclei and secretory granules after short GA-CF-FD. In the latter group of specimens a correlation could be found between smaller nuclear areas and more irregular shapes. The differences in morphological variables between the two preparation protocols might be due to a better protein stabilization and a reduced collapse of macromolecules after the 2 hr GA fixation, strengthened by the chemical dehydration. The specific immunolabeling with antiserum to growth hormone was much greater but more varied after short time GA-CF-FD than after long GA fixation. Epon surface topography over the granule area also differed: smooth after short time GA-CF-FD and furrowed after long GA fixation. Our results, demonstrating important differences in morphological parameters and immunolabeling density between two common preparation protocols, seem critical for more reliable interpretation in quantitative immunoelectron microscopy. We also emphasize the need for computer assisted image analysis and measurements in immunoelectron microscopy to ensure objective evaluations.

Animals↗
PubMed1993

Automatic quantitative evaluation of autoradiographic band films by computerized image analysis.

The present paper describes a new image processing method for automatic quantitative analysis of autoradiographic band films. It was developed in a specific image analysis environment (IBAS 2.0), but the algorithms and methods can be utilized elsewhere. The program is easy to use and presents some particularly useful features for evaluation of autoradiographic band films, such as the choice of whole film or single lane background determination; the possibility of evaluating bands with film scratch artifacts and the quantification in absolute terms or relative to reference values. The method was tested by comparison with laser-scanner densitometric quantifications of the same autoradiograms. The results show the full compatibility of the two methods and demonstrate the reliability and sensitivity of image analysis. The method can be used not only to evaluate autoradiographic band films, but to analyze any type of signal bands on other materials (e.g. electrophoresis gel, chromatographic paper, etc.).

Autoradiography↗
PubMed2005

Development and application of image analysis to quantify calcium lactate crystals on the surface of smoked Cheddar cheese.

Calcium lactate crystals that form white specks or haze on the surface of cheese constitute a significant quality problem for producers of Cheddar cheese. Subjective methods to evaluate crystal coverage of cheese surfaces have been reported previously, but objective methods are currently lacking. The objectives of this work were to develop and evaluate an objective method to measure the area occupied by calcium lactate crystals on surfaces of naturally smoked Cheddar cheese samples using digital photography and image analysis. Coefficients of variation ranged from 1.29 to 4.68% for 5 replicate analyses of 3 different cheese surfaces that ranged from approximately 2 to 49% of total surface area occupied by crystals. Thus, results showed a high degree of repeatability for the 3 cheese surfaces, which ranged from very slight and geometrically simple to very heavy and geometrically complex crystal coverage. The method underestimated total area occupied by crystals on the 3 surfaces by 0.24 to 4.83% unless the fainter crystal regions that went undetected during initial thresholding were manually segmented and quantified. The wet weight of crystal substance collected per unit of surface area from 20 different cheese samples increased exponentially as the percentage of total surface area occupied by crystals increased. These data were consistent with subjective observations that crystal regions appeared to grow vertically as well as horizontally as they expanded to occupy greater surface area. Image analysis was well suited for evaluating changes in crystal coverage during cheese aging because measurements were made nondestructively and with minimal disruption to the cheese. The area occupied by crystals on 6 different surfaces from 3 different cheese samples increased linearly (R2 = 0.94 to 0.99) during storage at 4 degrees C for up to 33 wk. However, the rates of increase differed significantly among the 3 cheese samples. Image analysis may serve as a useful tool to quantitatively evaluate the effects of factors such as cheese composition, packaging conditions and storage temperature on rate of crystal growth and time of crystal appearance during storage.

Calcium Compounds↗
PubMed2005

Fluorometric and fluorescent image analysis methods for determination of lipid hydroperoxides in oil models with 3-perylene diphenylphosphine (3-PeDPP).

Fluorometric and fluorescent image analysis methods with 3-perylene diphenylphosphine (3-PeDPP) were developed to measure lipid hydroperoxides in refined tuna oil. The fluorescence intensity of 3-perylene diphenylphosphineoxide (3-PeDPPO, the corresponding peroxidation product of 3-PeDPP) has been used for assessing lipid hydroperoxides in refined tuna oil models, and the results are compared to those of a classical method using ferric-xylenol orange complex. There were good correlations between the lipid hydroperoxide contents determined by the 3-PeDPPO fluorescence and the xylenol orange methods (R(2) = 0.984). Moreover, the novel probe 3-PeDPP and the fluorescent image analysis enabled us to evaluate two-dimensionally the lipid hydroperoxide contents in tuna oil droplets. These results suggest that the fluorometric and fluorescent image analyses using 3-PeDPP would be suitable for batch and two-dimensional determinations of lipid hydroperoxides in oil and oil-containing materials.

Animals↗
PubMed2005

The measurement of tooth whiteness by image analysis and spectrophotometry: a comparison.

Digital image capturing and analysis techniques have been used to measure the colour of teeth and to compare with spectrophotometric results and visual observations. A non-linear image analysis approach was developed and, for the colour range of human teeth, allows device-dependant digital camera colour data to be quantitatively transformed to Commission Internationale de l'Eclairage (CIE) colorimetric values. With reference to a CIE standard illuminant, two different lighting arrays have been used. For flat and non-translucent white and yellow surfaces, spectrophotometric results showed that this transformation achieves required accuracy. It was found, in all of the present studies, which included measurements on the VITA Lumin Vacuum shade guide and extracted teeth, that spectrophotometry invariably underestimated values of the CIE whiteness index. However, the results from these two types of measurement correlated well. There was also a reasonably good correlation between earlier data obtained by visual assessment and the present data by the two instrumental methods. For extracted teeth, both instrumental methods used in this work did not confirm a whitening effect for 2-min brushing with toothpaste, but did show significant whitening results for bleaching with 15% hydrogen peroxide.

Algorithms↗
PubMed2004

Quantitative image analysis of estrogen receptors in breast fine needle aspiration biopsies.

OBJECTIVE: To establish whether the results of quantitative evaluation of estrogen receptors (ERs) in cytologic fine needle aspiration (FNA) biopsies of the breast are comparable to the results obtained on excised breast tumors and therefore suitable for making a clinical decision on tamoxifen treatment in women who are not candidates for surgery. STUDY DESIGN: We performed a retrospective review of 118 breast FNA specimens that were positive for adenocarcinoma cells, had adequate cell block cellularity and provided subsequent surgical resection tissue. Quantification of ERs was performed on cell block material and follow-up tissue sections by the Chromavision Automated Imaging System, San Juan Capistrano, California, U.S.A. RESULTS: Quantitative image analysis provided consistently reliable, comparable results when evaluating for the presence or absence of ERs (at a 5% staining cutoff level), with 98.3% agreement between FNA cytology and histology specimens. Quantitative measurements of FNA samples showed the best agreement with the values derived from the subsequent surgical specimens at high-end (> 85% staining) and low-end (< 10% staining) values. However, a direct linear correlation of values was not observed. In the great majority of parallel measures, ERs were either strongly positive (> 75% staining) or had a zero value, particularly in the surgical specimens, with more "in-between" values identified in FNA specimens. CONCLUSION: Quantitative image analysis of FNA of ER results are comparable to those of surgical excision specimens and can be used for therapeutic decision making. The utility and advantages of quantitative ERs by image analysis include providing the patient and physician with important early prognostic and diagnostic information before planning a surgical approach. Additionally, FNA ERs are useful in determining therapy alternatives in patients who are not surgical candidates and in evaluating the preoperative hormone status of patients receiving chemotherapy prior to surgery.

Adenocarcinoma↗
PubMed1986

Quantitative evaluation of neonatal lung expansion with automated image analysis.

Lung sections from artificially ventilated premature newborn rabbits, some treated with natural surfactant, were examined microscopically with an IBAS image analyzer connected to a television camera. The "stereological profile" of the alveoli was determined by automatical evaluation of the following parameters: volume density (VV), and its coefficient of variation (CV(VV), surface density (SV), average mean integral surface curvature (K), and a "shape factor" (SF) measuring the "circularity" of sectioned alveoli. Data from image analysis were closely correlated to those obtained with conventional morphometrical techniques (e.g., r = 0.92 for VV). Alveolar expansion was significantly improved after treatment with surfactant, especially in animals ventilated with prolonged inspiration phase. We suggest that image analysis is a useful method for evaluating alveolar expansion patterns in the neonatal lung.

Animals↗
PubMed1998

Image analysis of androgen receptor immunostaining in prostate cancer accurately predicts response to hormonal therapy.

PURPOSE: Immunostaining for androgen receptor in prostate tumor specimens has revealed that the majority of primary and advanced stage cancers are positive for this regulatory transcription factor. Consequently, its use as a marker for tumor behavior and therapeutic response has been discounted. However, past reports have noted significant heterogeneity of androgen receptor immunostaining between prostate tumor cells in contrast to staining homogeneity in normal epithelium, which indicates that variability in androgen receptor content may exist within certain tumor specimens. To analyze this phenomenon more thoroughly and to determine whether this variability possesses clinical correlates, androgen receptor immunostaining profiles within androgen receptor positive prostate tumor specimens were categorized using an image analysis based system. MATERIALS AND METHODS: Tumor specimens were obtained before hormone therapy from 44 patients with advanced stage prostate cancer and 4 with early stage disease who later had progression. Response to antiandrogen therapy and survival was monitored. Paraffin embedded tumor sections were processed for immunocytochemistry and stained for androgen receptor. A Quantimet image analysis system was used to analyze nuclear immunostaining for androgen receptor and Receptogram patterns were established for each specimen based on univariate distributions of nuclear receptor content and concentration. RESULTS: Data revealed that 17 of 18 responders to hormone therapy possessed type 1 (15) or type 3 (2) Receptograms, which are characterized by a unimodal peak or multimodal peaks within a narrow concentration range. Of the 17 cases that stabilized following therapy 16 had type 3 Receptograms and 1 was characterized as type 1. In contrast, all 13 patients in whom endocrine treatment failed had either type 2 or 4 Receptograms, which are characterized by a highly skewed or bimodal androgen receptor distribution. Positive and negative predictive values for this assay were 100 and 93%, respectively. In addition, the type 1/3 Receptogram patterns were correlated with longer mean survival. CONCLUSIONS: Image analysis of prostate cancer androgen receptor immunostaining with a pattern oriented approach for response is capable of accurately predicting response to hormone therapy in patients with advanced stage disease. Application of this analytic scheme may assist the clinician with therapeutic management of advanced prostate cancer.

Adenocarcinoma↗
PubMedDate not supplied

An image analysis system for the quantification of invasion in vitro.

We have tested the value of a computer-assisted image analysis program for the quantitative study of invasion in vitro using experiments that were previously described semi-quantitatively. Mouse fibrosarcoma cell (MO4) aggregates were confronted with precultured fragments of embryonic chick heart in organ culture. Confronting pairs were fixed after 1, 2, 3 and 4 days, and processed for paraffin sectioning and immunostaining with an antiserum against chick heart. The image analysis system allowed separate quantification of two aspects of invasion, namely, occupation of the heart tissue by MO4 cells and degeneration of the invaded heart tissue. Complex combination of occupation and invasion added a qualitative aspect of invasion that has not been described previously and that revealed qualitative differences in invasion under various circumstances.

Animals↗
PubMed1999

A simple index using video image analysis to predict disease outcome in primary breast cancer.

Image analysis was used to investigate the prognostic significance of immunostaining for oestrogen receptor (ER), p53 tumour-suppressor protein and tumour cell proliferation (MIB-1) in a random cohort of 200 primary breast cancer patients with between 4 and 7 years of clinical follow-up. Image measurements of the percentage of immunopositive cancer cell nuclei (% positive nuclear area) were recorded for the above tumour features for each patient. Assessment of relative risk using Cox's univariate analysis indicated that tumour size, number of cancer-involved nodes, MIB-1 and ER % positive nuclear area were significantly associated with breast cancer disease outcome, i.e., relapse-free survival and overall survival. In multivariate analysis, tumour size, number of involved nodes, ER and MIB-1 % positive nuclear area were retained as independent predictors of prognosis, depending on the image measurement cut-point used. A prognostic model, which can be used without reference to nodal involvement, was constructed for tumour size, ER cut-point of 30% positive nuclear area and MIB-1 cut-point of 10% positive nuclear area. Kaplan-Meier analysis of this image-based prognostic index identified 4 risk groups with predicted 5-year overall survival rates of 93%, 83%, 76.7% and 61.5%. We conclude that image measurements of ER and proliferative rate can be combined with tumour size to construct a prognostic index which reliably predicts disease outcome in primary breast cancer without knowledge of the nodal status of the patient.

Adult↗
PubMedDate not supplied

Digital radiology and image analysis for approximal caries diagnosis.

The aim of this study was to determine if radiology combined with digital reception and image analysis, radiovisiography (RVG), is effective in the early diagnosis of simulated approximal carious lesions. An experimental lesion similar to the one produced by caries was made in 39 permanent molars and premolars. Radiographic images of these lesions were obtained under standardized conditions using RVG. The image obtained was magnified 700 times and the densities of the lesion, the enamel, the dentin, and the pulp were measured using an image analysis program (Visualdent). The results showed statistically significant differences between the density of the produced lesions and that of healthy enamel. This measurement was independent of the differing thickness of the approximal enamel surface in molars and premolars. These results indicated the potential usefulness of the system tested in the diagnosis of incipient approximal caries.

Dental Caries↗
PubMed1988

A new method for the comprehensive automatic morphologic image analysis of Langerhans cells.

Standard techniques used to study Langerhans cell (LC) populations are tedious and time-consuming. We developed a rapid and comprehensive method to evaluate LC using automatic digital image analysis. Human epidermal sheets were stained with OKT6 monoclonal antibody and evaluated on an IBAS 2000 computerized automatic digital image analysis system. The fields were imaged on a Photomicroscope I using a high-resolution monochrome video camera. Each field was digitized, normalized, and filtered. The LC were discriminated by density; each field was interactively edited to separate overlapping cells and to bridge small gaps in the dendrites. The discriminated binary image of the LC was measured for number of cells per field, total area of individual cells per field, and percent of the field occupied by LC. The cell bodies were then separately discriminated and subtracted from the thinned cell image to allow a separate measurement of number and length of dendrites per cell. Finally, the binary cell image in a reference section was dilated to occupy approximately the total field area. This degree of dilation was then applied to all subjects to give the "area of influence." This methodology provides a rapid and comprehensive tool for the evaluation of LC.

Autoanalysis↗
PubMed1997

Uveal melanoma: the importance of large nucleoli in predicting patient outcome--an automated image analysis study.

BACKGROUND: Automated image capture and analysis (AICA) has not previously been used to measure the size of nucleoli in uveal melanoma. In this study, the measurements were tested for a possible association with patient outcome. METHODS: Sections from 63 uveal melanomas were stained using the silver stain for nucleolar organizing regions (AgNOR). AICA was used to measure the following five nucleolar features in ten microscopic fields of the tumor: area, circularity, maximum diameter, width, and length of the perimeter. For each tumor, the mean and standard deviation of each of the features were calculated based on all the nucleoli and on subsets of nucleoli with larger areas. For the five nucleolar features the mean of the largest value (MLV) in each of the ten fields was calculated. For comparison, a related visually measured nucleolar feature (MLN) was obtained from hematoxylin and eosin stained sections using a filar micrometer. RESULTS: Thirty-four patients died with metastatic disease and 29 patients survived at least 5 years without metastasis. A greater proportion of nucleoli larger than 3 mm2 in greatest dimension were from patients who died of their disease. The means of the nucleolar features were less significant outcome discriminators than the standard deviations. Means and standard deviations based on subgroups of nucleoli larger than 3 or 3.5 mm2 in greatest dimension were better discriminators. The MLVs were as effective discriminators as the corresponding standard deviations of the larger nucleoli and were better discriminators than MLN. CONCLUSIONS: AICA of AgNOR stained sections of uveal melanoma provides an excellent method for predicting the outcome of patients with uveal melanoma.

Automation↗
PubMed2003

A multi-scale probabilistic network model for detection, synthesis and compression in mammographic image analysis.

We develop a probabilistic network model over image spaces and demonstrate its broad utility in mammographic image analysis, particularly with respect to computer-aided diagnosis. The model employs a multi-scale pyramid decomposition to factor images across scale and a network of tree-structured hidden variables to capture long-range spatial dependencies. This factoring makes the computation of the density functions local and tractable. The result is a hierarchical mixture of conditional probabilities, similar to a hidden Markov model on a tree. The model parameters are found with maximum likelihood estimation using the expectation-maximization algorithm. The utility of the model is demonstrated for three applications: (1) detection of mammographic masses for computer-aided diagnosis; (2) qualitative assessment of model structure through mammographic synthesis; and (3) compression of mammographic regions of interest.

Female↗
PubMed1991

Dynamic image analysis applied to the study of ciliary beat on cultured ciliated epithelial cells from rabbit trachea.

We have developed an automated image analysis method to study the ciliary beat frequency of ciliated cells of the primary culture from rabbit trachea. The ciliated outgrowth image is digitized and the variation in optical density is automatically calculated for each selected area of interest. 32 measurements of ciliary beat frequency are, in this way, calculated simultaneously in 6 min. With this reliable device, some studies on baseline frequency of control culture have been carried out. There was no variation in the mean frequencies of ciliated cells of the primary culture of different tracheas in our culture conditions. Moreover, the values of ciliary beat frequency at the starting point of the outgrowth were similar to those at the periphery of the outgrowth. There is nevertheless a slow decrease in frequencies versus the duration of culture. We have also established that the frequency of ciliary beat of some cells fluctuates in a periodic pattern whereas the majority of the ciliated population beat in a stable way. The image analysis process allows us to perform a cartography of frequencies on the video display. It also allows us to have access to the frequency of one cilium. Our method therefore seems to be reliable and furthermore simple in the evaluation of the potential effect of inhaled toxic compounds on ciliated cells of mammalian respiratory tract.

Animals↗