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PubMed1994

Global and regional detection of induced optic disc change by digitized image analysis.

OBJECTIVE: To evaluate two new strategies for the detection of optic disc change within individual eyes by digitized image analysis. METHODS: Eleven normal optic discs of 11 monkeys were imaged with a digital imaging system (Topcon Imagenet, Topcon Instrument Corporation of America, Paramus, NJ) at two intraocular pressures (10 and 45 mm Hg). To detect global change in the disc, we compared conventional optic disc parameters with a new optic disc parameter: mean position of the disc. To detect regional change, the 95% confidence interval for change was calculated for each data point and mapped for each disc. RESULTS: Posterior deformation of the disc surface was detected in seven of 11 eyes using conventional parameters and in 10 of 11 eyes using mean position of the disc. Regions of posterior deformation were detected by 95% confidence interval for change mapping in all 11 discs as localized areas of confluent, posteriorly displaced points. CONCLUSIONS: Mean position of the disc outperformed conventional measurements in the detection of global optic disc change. Ninety-five percent confidence interval for change mapping may allow individual data point-based focal and regional analysis of the disc.

Animals↗
PubMed1987

Multispectral magnetic resonance image analysis.

Multiecho magnetic resonance (MR) scanning produces tomographic images with approximately equal morphologic information but varying gray scales at the same anatomic level. Multispectral image classification techniques, originally developed for satellite imaging, have recently been applied to MR tissue characterization. Statistical assessment of multispectral tissue classification techniques has been used to select the most promising of several alternative methods. MR examinations of the head and body, obtained with a 0.35, 0.5, or 1.5T imager, comprised data sets with at least two pulse sequences yielding three images at each anatomical level: (1) TR = 0.3 sec, TE = 30 msec, (2) TR = 1.5, TE = 30, (3) TR = 1.5, TE = 120. Normal and pathological images have been analyzed using multispectral analysis and image classification. MR image data are first subjected to radiometric and geometric corrections to reduce error resulting from (1) instrumental variations in data acquisition, (2) image noise, and (3) misregistration. Training regions of interest (ROI) are outlined in areas of normal (gray and white matter, CSF) and pathological tissue. Statistics are extracted from these ROIs and classification maps generated using table lookup, minimum distance to means, maximum likelihood, and cluster analysis. These synthetic maps are then compared pixel by pixel with manually prepared classification maps of the same MR images. Using these methods, the authors have found that: (1) both supervised and unsupervised classification techniques yielded theme maps (class maps) which demonstrated tissue characteristic signatures and (2) tissue classification errors found in computer-generated theme maps were due to subtle gray scale changes present in the original MR data sets arising from radiometric inhomogeneity and spatial nonuniformity.

Brain↗
PubMed2006

Characterization and quantification of the skin radiance through new digital image analysis.

BACKGROUND/AIMS: The individual perception of the radiance is difficult to define and quantify because it often includes physiological and psychological attributes. Although if they are differences in the perception of the skin radiance, dermatologists and experts in cosmetology consider that the complexion must reflect the general health of an individual. The aim of this work was to determine existing conditions of skin radiance via digital image analysis, consumer's perception and experts' evaluation, and propose a mathematical model to quantify the global radiance phenomenon. METHODS: A round table meeting was organized in order to have free discussions about skin radiance. The qualitative assessment of skin radiance was carried out using a self-assessment questionnaire constructed according to the information obtained from the round table meeting. A simplified version of this questionnaire was proposed to experts. One hundred female subjects belonging to three different age groups (20-30, 30-40, 40-50 and >50 years old) participated in the study. Facial images were taken using a video imaging with visual control system to ensure consistency of images among volunteers. From these images, algorithms based on the principle of polynomial approximation, segmentation by maximalization of the entropy and the Logarithmic Image Processing model were required to extract skin radiance parameters. Multiple regression analysis was used to establish, via consumer's perception of the skin radiance and experts' evaluation studies, the degree to which each of the independent parameters contributes to the skin radiance perception. RESULTS: All the items of the self-assessment questionnaire explained 74% of the variation of the skin radiance. Data from experts' analysis explained 87% of the variation of skin radiance. In the two cases, skin radiance appeared to be independent of age and the presence of wrinkles. From the image analysis, we observed that the skin surface parameters explained 20% of the variation of the skin radiance expressed by experts and 24% of the variation of the skin radiance expressed by volunteers. As a result, about 80% of the variation is not explained by the instrumental data. If we combine experts' analysis and instrumental data, we obtain a mathematical model that explains 92% of the variation of the skin radiance. CONCLUSION: The questionnaire constructed from this brainstorming session allowed volunteers and experts to judge their perception of skin radiance more precisely. Video imaging appears as an interesting method to quantify visual properties of the skin and to visualize what the consumer perceives of skin radiance. However, the mathematical model proposed from the skin surface parameters analysis does not totally explain the global perception of skin radiance. In the future, it will be necessary to develop new data-processing programs to quantify subjective parameters in order to validate our mathematical model.

Adult↗
PubMed1997

Responses of rat nasal epithelium to short- and long-term exposures of ozone: image analysis of epithelial injury, adaptation and repair.

This article reviews the use of computerized image analysis and standard morphologic techniques to characterize the responses of nasal epithelium in laboratory rats to single or repeated exposures to a common urban air-pollutant, ozone. Alterations in the number and composition of the epithelial cell populations after either short- or long-term exposures are described. The principal nasal epithelial alteration induced by repeated exposures to this irritating, oxidant pollutant is mucous cell metaplasia (i.e., transformation of airway epithelium, normally devoid of mucous cells, to a secretory epithelium containing numerous mucus-secreting cells). This metaplastic change, induced by acute or chronic ozone exposures, has been morphometrically examined at various times post-exposure. In this article, we describe our current understanding of the pathogenesis and persistence of ozone-induced mucous cell metaplasia in nasal epithelium based on the results of these morphometric studies.

Animals↗
PubMed2006

Semiautomated computer-assisted image analysis to quantify 3,3'-diaminobenzidine tetrahydrochloride-immunostained small tissues.

This work aimed to develop a technique to measure stained areas in images from sample tissue sections, namely when the structure of interest does not fill the entire image field of the microscope. We propose a semiautomated computer-assisted image analysis (SACAIA) method in which brightfield color images of 3,3'-diaminobenzidene tetrahydrochloride (DAB)-stained antigens are converted to their blue component and boundaries are delineated to extract the object of interest. The number of pixels of a defined color (elicited by DAB) is counted and used to measure the stained area relative to the total area of the tissue under study. The percentages of area stained with adenosine A(1) receptor were 40.76+/-2.08 and 42.44+/-2.26% for manual analysis and SACAIA, respectively (P=0.582). A strong linear correlation of A(1) receptor quantification was found (r=0.98, P<0.001, and 95% CI=0.97 to 0.99 for manual method; r=0.99, P<0.001, and 95% CI=0.98 to 0.99 for SACAIA method). The extent to which misclassification affected staining quantification was evaluated by Bland-Altman analysis, indicating that this method can be applied accurately to quantify the immunohistochemical staining area (occupied by a specific antigen) in small sample tissues that do not fill the entire image field of the microscope.

3,3'-Diaminobenzidine↗
PubMed1991

[Optic disc measurements with computerized image analysis in normals, ocular hypertensives and glaucomas].

Optic disc measurements were performed with computerized image analysis (Rodenstock Optic Nerve Head Analyzer) in one eye of each patient of 74 normal controls, 41 ocular hypertensives and 41 patients with early stage glaucoma. In normal controls, the rim area was 1.62 +/- 0.48 mm2 (mean +/- s.d.), cup area 0.80 +/- 0.41mm2, cup volume 0.34 +/- 0.16mm3, cup/disc ratio 0.43 +/- 0.19. For Ocular hypertensives, rim area was 1.32 +/- 0.44mm2, cup area 1.32 +/- 0.78mm2, cup volume 0.56 +/- 0.41mm2, cup/disc ratio 0.51 +/- 0.41. For glaucomas, the rim area was 1.07 +/- 0.47mm2, cup area 1.3 +/- 0.78mm2, cup volume 0.75 +/- 0.40mm3, cup/disc ratio 0.65 +/- 0.19. Statistically significant differences were found among the three groups for these parameters. In spite of the wide distribution and overlap of the values of optic disc parameters among the three groups, normal subjects with an optic disc area of greater than or equal to 3.0mm2 showed clear differences in optic disc parameters compared to ocular hypertensive and glaucoma cases. From these results, cases with larger discs seem to be more vulnerable to raised IOPs.

Glaucoma, Open-Angle↗
PubMed1989

Variations with age in the topographic distribution of coronary atherosclerotic lesions as assessed by image analysis.

The localization of macroscopic coronary atherosclerotic lesions was investigated for 184 cases by image analysis. Atherosclerotic lesions were classified into 2 types: fatty streaks and raised lesions. The overall distribution of fatty streaks in arteries involved only by fatty streaks and the distribution of raised lesions in those arteries having raised lesions were demonstrated at similar sites in 3 coronary vessels. If the localization of lesions was examined within age groups, those sites involved with fatty streaks in one age group were replaced with raised lesions in the next older age group; fatty streaks in this older group were located distally to the raised lesions. Subsequently the areas occupied with fatty streaks were replaced with raised lesions in the next older age group. Furthermore, raised lesions seldom appeared at the site where fatty streaks had not existed in the preceding age group. Similar changes in topographic distribution were present if such changes were analyzed according to extent of atherosclerosis. Data from cases with myocardial bridges show that both fatty streaks and raised lesions are seldom observed in the region distal to myocardial bridge. We conclude, thus, that fatty streaks are the precursors of raised lesions in the coronary artery.

Aging↗
PubMed1989

Quantitation of antigen in tissue by immunofluorescence image analysis.

A method is described to measure antigen(s) in tissue section using an image analysis system to quantitate immunofluorescence following staining with fluorescein isothiocyanate (FITC)-conjugated antibody. The antigen utilized was an 125I-labeled goat anti-glomerular basement membrane antibody (1409 cpm/micrograms) administered intravenously to each of 11 Sprague-Dawley rats in doses ranging from 1.09 to 34.72 mg IgG. 24 h later, both kidneys were obtained for quantitative immunofluorescence following staining of tissue sections with FITC-labeled rabbit anti-goat IgG and for determination of radioactivity which reflects the amount of goat IgG present in isolated glomeruli. A linear correlation (r = 0.97) was observed between the dose of administered goat 125I-IgG and the amount bound to isolated glomeruli over the entire dosage range. A highly significant correlation (r = 0.98) was also seen between the mean brightness per glomerulus as determined by quantitative immunofluorescence and the amount of 125I-IgG bound per glomerulus but only at values less than 500 pg of IgG per glomerulus. Above these levels no correlation was observed, suggesting the presence of hidden epitopes in the bound goat IgG or the lack of availability of the FITC-labeled rabbit antibody.

Animals↗
PubMed2000

Topography of genetic loci in tissue samples: towards new diagnostic tool using interphase FISH and high-resolution image analysis techniques.

Using single and dual colour fluorescence in situ hybridisation (FISH) combined with image analysis techniques the topographic characteristics of genes and centromeres in nuclei of human colon tissue cells were investigated. The distributions of distances from the centre-of-nucleus to genes (centromeres) and from genes to genes (centromeres to centromeres) were studied in normal colon tissue cells found in the neighbourhood of tumour samples, in tumour cell line HT-29 and in promyelocytic HL-60 cell line for comparison. Our results show that the topography of genetic loci determined in 3D-fixed cell tissue corresponds to that obtained for 2D-fixed cells separated from the tissue. The distributions of the centre-of-nucleus to gene (centromere) distances and gene to gene (centromere to centromere) distances and their average values are different for various genetic loci but similar for normal colon tissue cells, HT-29 colon tumour cell line and HL-60 promyelocytic cell line. It suggests that the arrangement of genetic loci in cell nucleus is conserved in different types of human cells. The investigations of trisomic loci in HT-29 cells revealed that the location of the third genetic element is not different from the location of two homologues in diploid cells. We have shown that the topographic parameters used in our experiments for different genetic elements are not tissue or tumour specific. In order to validate high-resolution cytometry for oncology, further investigations should include more precise parameters reflecting the state of chromatin in the neighbourhood of critical oncogenes or tumour suppresser genes.

Cell Nucleus↗
PubMed1997

Clinical significance of negative and equivocal urinary bladder cytology alone and in combination with DNA image analysis and cystoscopy.

BACKGROUND: We evaluated the individual and combined ability of cytology (CYT), image analysis (IA), and cystoscopy (CYSTO) to predict the presence of transitional cell carcinoma (TCC) at 6 months of follow-up in patients with or without a prior history of urothelial carcinoma and negative (NEG) or equivocal (atypical or suspicious) urinary CYT. METHODS: Fifty-one patients (43 with prior TCC) provided 57 urinary samples that were evaluated by CYT and DNA IA. Forty-nine patients were evaluated by CYSTO. Disease status was reassessed at 6 months by a combination of clinical, CYSTO, CYT, and histologic follow-up. RESULTS: At 6 months' follow-up, the incidence of recurrence for patients with diploid, broad diploid, or aneuploid DNA histograms was 38%, 73%, and 100%, respectively. In the same group of patients, 43% of patients with NEG and "atypical" CYT recurred compared with 83.3% of patients with "suspicious" CYT. The predictive value (PV) of a positive (+) CYSTO evaluation was 100%; however, a NEG CYSTO examination was correct in only 73% of cases. Sensitivities of CYT, IA, and CYSTO to predict recurrence were 54%, 59%, and 62.5%, respectively, whereas the combined sensitivity of all three modalities was 72%. The +PV of combined CYT and IA in patients with prior TCC was 90% with aneuploidy 100% specific for malignancy; the NEG PV of combined CYT, IA, and CYSTO was 70%. CYT, IA, and CYSTO were highly significant in predicting recurrence (P = 0.0017, P = 0.0026, and P = 0.0002, respectively) whereas tumor grade and degree of invasiveness as assessed on initial biopsy were not significant. However, 11% of patients recurred between 6 months to 1 year who had NEG CYT, NEG CYSTO, and NEG IA. CONCLUSIONS: Diagnostic accuracy increases in patients with NEG or equivocal CYT if supplemented by DNA IA and CYSTO. In patients with no history of TCC, equivocal urine CYT and/or abnormal DNA IA can occur after chemotherapy, radiation therapy, or viral infection. In these patients, the combined approach together with accurate history is essential for correct diagnosis. For the small subpopulation of patients who recur but demonstrate no abnormalities on combined testing, more sensitive diagnostic tests, such as chromosomal abnormalities by in situ hybridization, need to be developed.

Adult↗
PubMed1991

Measurement of human hair growth by optical microscopy and image analysis.

We have developed a quantitative method for measuring hair growth using optical microscopy and image analysis, and have used this to investigate the rate of growth in subjects with and without alopecia. The hairs were cut from an area 7-8 mm in diameter and 24 h and 72 h later, images of the areas were obtained using an optical microscope and were recorded on a video disc. Measurements of the regrowing hairs, placed parallel to the scalp using a glass slide attached to the front of the microscope, were made using the image analyser. In subjects with little or no baldness there was a clear difference between fast-growing hairs and resting or slow-growing hairs. However, in subjects with alopecia there was no such difference and the growth rate of all the hairs showed a continuous distribution. Using this method other parameters such as the number of hairs per unit area and hair diameter as well as grouping of the hairs could be measured.

Adult↗
PubMedDate not supplied

Image analysis of helical objects: the Brandeis Helical Package.

Although the fundamental steps in Fourier-based image analysis of electron micrographs of helical structures have not changed significantly since the techniques were developed 30 years ago, there have been developments which aid both the analysis itself and the interpretation of results. Increases in computational resources have allowed the automation of many of the repetitive steps in image processing. We describe here a set of computer programs which have been developed at Brandeis University over the past 10 or more years. These programs, referred to as the Brandeis Helical Package, are designed to operate independently of each other with a simple and more uniform protocol for the flow of information between them. The programs are now easier to understand and to use and therefore represent a good tool for the analysis of helical structures.

Actins↗
PubMed1995

Spiral ganglion cell survival in labyrinthitis ossificans: computerized image analysis.

Obstruction of the cochlear scale by ossification and fibrosis, which can now be imaged by computed tomography, has been proposed as a predictor of ganglion cell survival. Subjects for this histopathologic temporal bone study were 12 profoundly deaf patients with labyrinthitis ossificans. Controls without ossification were 16 normal-hearing patients and 16 profoundly deaf patients. All temporal bones were graphically reconstructed. Computerized image analysis obtained the percentage of scalar obstruction in 12 temporal bones with labyrinthitis ossificans. Statistical analyses could demonstrate no relationship between spiral ganglion cell survival and obstruction. There was much interindividual variability in ganglion cell count among the 44 temporal bones. Ganglion cell survival was significantly less in the two deafness groups than in the normal group, but did not differ significantly between the two deafness groups. Therefore, cochlear labryinthitis ossificans is not a preditor of ganglion cell survival and should not be a contraindication to cochlear implantation.

Adolescent↗
PubMed1990

Computer image analysis method for rapid quantitation of macrophage phagocytosis.

A new method is described for rapidly quantitating phagocytosis by adherent macrophages in culture using computer image analysis (CIA) of video light microscopic images. Ingestion of fluorescent microspheres by peritoneal murine macrophages is used to model phagocytosis. The grey levels of digital phase contrast and fluorescent microscopic images are used to quantitate the number of microspheres per cell. The method is semi-automatic, analyzes approximately 2 x 10(3) cells/hr, and simultaneously measures phagocytosis (microspheres/cell), cell area, and density (number of cells/mm2). CIA obtains the same microspheres/cell average as manual microscopic counting and an analytical precision of 5%. As expected, CIA found that the number of microspheres/cell linearly increases with increasing macrophage-microsphere co-culture time or increasing microsphere concentration until macrophages become saturated. CIA finds increased phagocytosis by interferon-gamma-treated cells and suppressed phagocytosis by cytochalasin B- or 4 degrees C-treated cells relative to controls, which demonstrates that CIA can resolve biological changes in macrophage phagocytosis. CIA also provides quantitative data on macrophage morphometry and density and found an increase in the cell area and density of INF treated macrophages. CIA provides significantly more phagocytic, morphometric, and density data than conventional manual microscopic counting methods or flow cytometric methods. The limitations, improvements, and future applications of this method are discussed.

Humans↗
PubMed1992

Image analysis of stage 1 melanoma (1.00-2.50 mm): lymphocytic infiltrates related to metastasis and survival.

Image analysis of histologic sections of 11 patients with clinical Stage 1 melanoma, 1.00 mm-2.50 mm, who developed metastasis, was done to determine the significance of lymphocytic infiltrates relative to metastasis and survival. An age, sex, site, and thickness matched control group of non-metastasizing clinical Stage 1 melanoma revealed no significant difference in the lymphocytic infiltrate parameters from the metastasizing group with the exception of the ratio of lymphocyte infiltrate width to the tumor width (p = 0.003). Increased lymphocytic infiltrates within the tumor and subjacent to its base significantly correlated with delayed time to metastasis (p = 0.014 and p < 0.001, respectively) and longer survival period (p = 0.045 and p < 0.001, respectively). Lymphocytic infiltrate area at the tumor base in relation to tumor area was of prognostic value: the larger the ratio, the greater the time interval from metastasis to death (p = 0.008).

Humans↗
PubMed1991

Computer-assisted image analysis assay of human neutrophil chemotaxis in vitro.

We have developed a computer-based image analysis system to measure in-filter migration of human neutrophils in the Boyden chamber. This method is compared with the conventional manual counting techniques. Neutrophils from healthy individuals and from patients with reduced chemotactic activity were used. The cells migrating into the filter were counted automatically at depths 20 microns apart commencing from the upper surface on the filter. The major advantages of this method are reproducibility and the counting of many fields which provides better data for statistical analysis of the results. Another advantage of the assay is that it can be used to show the migration pattern of different populations of neutrophils from both healthy individuals and patients.

Chemotaxis, Leukocyte↗
PubMed1990

Quantitation of in vitro ciliated cell growth through image analysis.

Ciliated cell cultures can be produced in outgrowths from explants of human respiratory epithelium. An image analysis technique was developed to quantify the percentage of active ciliated cells present in these cultures. The subtraction 2 by 2 of five successive video images of the cultures, followed by the addition of the resulting images, allowed the determination of the culture surface covered by ciliated cells. The percentage of this surface varied according to the region of the explant (27.7% in the outgrowth near the explant and 4.1% at the periphery of the outgrowth). High variations were observed within the same region of an outgrowth, as well as from one outgrowth to another. However, maximal differentiation was observed after 4 d of culture. The quantitation technique described in the present work might be useful for studying in vitro the respiratory epithelial injury and the subsequent repair processes.

Cell Membrane↗
PubMed1996

A new magnetic resonance imaging analysis method for the measurement of disc height variations.

STUDY DESIGN: A new magnetic resonance image analysis method is proposed which is based on the definition of the borders of the vertebral bodies adjacent to the intervertebral disc and their varying relationships. The reproducibility of this method (the so-called "centroid" method) was assessed by consecutive measurements. Its potential to depict diurnal disc height variations was studied using randomized groups of volunteers. OBJECTIVE: To determine if magnetic resonance imaging can reliably measure disc height variations in the lumbar spine in vivo. SUMMARY OF BACKGROUND DATA: A review of the literature indicates that noninvasive, accurate methods to study the effect of load on intervertebral discs in vivo are needed. METHODS: The reproducibility of the centroid method was assessed in 10 healthy volunteers in 2 consecutive measurements and compared to a conventional method (mean anterior and posterior disc height). To investigate the potential for the depiction of diurnal disc height variations, 10 volunteers were randomized in a study group (1 measurement in the morning, 1 measurement in the evening) and a control group (2 consecutive measurements in the morning). RESULTS: The centroid method allows the depiction of disc height variations as small as 0.85 mm with a 95% confidence (tolerance limits), whereas a conventional method needs variations of at least 1.66 mm. In the study (diurnal) group, the disc height decreased significantly (P < 0.0001) during the day (mean, -0.9 mm), while no variation (P < 0.8) was found in the control group. CONCLUSIONS: These results indicate that the centroid method can reliably detect disc height variations in an experimental setting. The centroid method provides the potential for evaluations of the effects of various work places, work equipment, work tasks, and postures.

Adult↗