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PubMed1995

Evaluation of image analysis and laser granulometry for microbial cell sizing.

A direct cell size measurement technique and an image analysis based sizing method were developed. The former consisted of a manual size measurement of the two-dimensional cell images on a video screen, with automatic data recording. This method was chosen as the reference. The latter, a semiautomatic method took advantage of a commercial computer program designed for image processing and particle morphology analysis. It gave average and median size values which were compatible with the manual method. However, the performance of these time consuming methods is limited. Hence, the laser granulometry technique, intrinsically far more powerful while capable of analysing millions of sample objects in a short time delay, was applied. The comparison revealed that this method gives too low size values, particularly in disagreement with the known dimensions of the bacterial (Zymomonas mobilis) cells. A size correction method was developed to realign the granulometry results of Z mobilis cell samples with those of the direct manual measurement method.

Bacteria↗
PubMed1997

Densitometric quantification of neuronal viability by computerized image analysis.

A new method is presented for the quantification of cell viability based on densitometry with computerized image analysis. Neuronal cells were stained with crystal violet and densitometric analysis was performed with an IBAS 2.0 image analyzer (Kontron/ Zeiss), using specially implemented dedicated software which integrates the optical density of the culture in each well with the area covered by the stained cells. To test the reliability of the densitometric method cortical cells were plated at different concentrations (5 x 10(4)-10(6)/ml); the standard curve obtained by analysis of crystal violet staining showed a linear proportion between cell number and optical density signal. The validation and accuracy of the method were assessed and compared with other methods using rat cortical cells cultured in vitro for 10 days and exposed to kainic acid (250 microM) for 24 h. Neuronal viability was reduced by 40-50% and comparison with direct cell counting, MTT assay, and spectrophotometric analysis confirmed that the method is simple, quick, and reliable.

Animals↗
PubMed2001

The quantification of dental plaque using an image analysis system: reliability and validation.

AIM: Established clinical indices used to measure dental plaque have limitations. The aim of this study was to develop and evaluate a new method of quantitative plaque measurement, with increased sensitivity and reproducibility, using a purpose designed image analysis system. METHOD: After plaque disclosure, the patient was positioned in a cephalometric head holder mounted in a custom-built frame with standard lighting and camera position. A 32-bit Digital Camera grabbed the image of the patient's teeth, which was analysed using Adobe Photoshop (V5.02, Adobe Systems Ltd, Europe) and Image Pro Plus software (V4.0, Media Cybernetics, USA). Measurements were made on 120 incisors in 15 patients and reproducibility was assessed using Fliess' Coefficient of Reliability. Sensitivity was assessed by comparison of results of treatment effects from a clinical trial involving 30 patients. Analysis of covariance was used to compare the image analysis system with the Turesky modification of the Quigley and Hein plaque index and the Addy plaque area index. RESULTS: The results were within the 'Excellent Reliability' category, for inter-operator reproducibility and intra-operator repeatability. CONCLUSIONS: This new system provided accurate quantitative measurements of dental plaque and labial tooth surfaces and was shown to have increased sensitivity when compared with the Turesky modification of the Quigley and Hein plaque index and the Addy plaque area index. The stored images can be re-measured for reliability and comparability between studies.

Analysis of Variance↗
PubMed1993

[Three-dimensional spatial texture of adenocarcinoma of the prostate by a combination of stereology and digital image analysis].

Second-order stereology combines stereology with stochastic geometry and digital image analysis to obtain an insight into the spatial architecture (texture) of tissues. In twenty radical prostatectomy specimens from patients with invasive adenocarcinomas of the prostate gland, the pair correlation function of the epithelial tissue component was estimated both for the carcinomatous and the tumour-free domains. After interactive segmentation of the gray level images, the method works fully automatically. The mean pair correlation function of carcinomatous tissue shows less clustering of epithelium at short distances and less rhythmicity of epithelium at long distances as compared to tumour-free tissue. This loss of glandular integrity is higher in cribriform than in tubular carcinomas. The results suggest that second-order stereology is a powerful tool for the objective evaluation of glandular differentiation.

Adenocarcinoma↗
PubMed1989

Digital image analysis for the diagnosis of periapical bone lesions: a preliminary study.

Digital image analysis techniques enable the problem of examiner variability to be circumvented, and can be used to develop quantitative descriptions of bone lesions. This study investigated a method for describing periapical bone lesions. An edge-detection technique was developed for application to routine periapical radiographs. Most periapical bone lesions appear radiographically as dark areas compared with the surrounding tissues. The digital imaging process resulted in an outline resembling the contour of the image of the lesion present. This contour could be successfully projected on to the original image with only limited operator assistance. Processing of the image resulted in increased definition of the structures present, with considerable noise reduction. The result was a simplified diagnostic examination process that promised a high degree of objectivity in periapical bone lesion detection. It is concluded that the results encourage further development of image processing techniques suitable for the definitive detection and diagnosis of periapical bone lesions.

Image Processing, Computer-Assisted↗
PubMed1993

Her-2/neu expression in node-negative breast cancer: direct tissue quantitation by computerized image analysis and association of overexpression with increased risk of recurrent disease.

The HER-2/neu proto-oncogene (also known as c-erb B-2) is homologous with, but distinct from, the epidermal growth factor receptor. Amplification of this gene in node-positive breast cancers has been shown to correlate with both earlier relapse and shorter overall survival. In node-negative breast cancer patients, the subgroup for which accurate prognostic data could make a significant contribution to treatment decisions, the prognostic utility of HER-2/neu amplification and/or overexpression has been controversial. The purpose of this report is to address the issues surrounding this controversy and to evaluate the prognostic utility of overexpression in a carefully followed group of patients using appropriately characterized reagents and methods. In this report we present data from a study of HER-2/neu expression designed specifically to test whether or not overexpression is associated with an increased risk of recurrence in node-negative breast cancers. From a cohort of 704 women with node-negative breast cancer who experienced recurrent disease (relapsed cases) 105 were matched with 105 women with no recurrence (disease-free controls) after the equivalent follow-up period. Immunohistochemistry was used to assess HER-2/neu expression in archival tissue blocks from both relapsed cases and their matched disease-free controls. Importantly, a series of molecularly characterized breast cancer specimens were used to confirm that the antibody used was of sufficient sensitivity and specificity to identify those cancers overexpressing the HER-2/neu protein in this formalin-fixed, paraffin-embedded tissue cohort. In addition, a quantitative approach was developed to more accurately assess the amount of HER-2/neu protein identified by immunostaining tumor tissue. This was done using a purified HER-2/neu protein synthesized in a bacterial expression vector and protein lysates derived from a series of cell lines, engineered to express a defined range of HER-2/neu oncoprotein levels. By using cells with defined expression levels as calibration material, computerized image analysis of immunohistochemical staining could be used to determine the amount of oncoprotein product in these cell lines as well as in human breast cancer specimens. Quantitation of the amount of HER-2/neu protein product determined by computerized image analysis of immunohistochemical assays correlated very closely with quantitative analysis of a series of molecularly characterized breast cancer cell lines and breast cancer tissue specimens.(ABSTRACT TRUNCATED AT 400 WORDS)

Biomarkers, Tumor↗
PubMed2000

A comparative study of MIB-1 staining indices of gliomas measured by NIH Image analysis program and conventional manual cell counting method.

To evaluate the NIH Image measured MIB-1 staining index (SI) as a useful tool for the determination of proliferative activity of gliomas, MIB-1 immunohistochemistry was performed on paraffin sections to estimate the proliferative activity of 50 gliomas. Five to eight RGB images at 200 magnifications were acquired per sample in a Macintosh computer using a RD-175 digital camera and Adope Photoshop program, followed by conversion of the RGB image to B (blue subtracted) and R (red subtracted) images and finally automatic cell counting of more than 1000 cells per sample by the NIH Image analysis program. The mean MIB-1 staining indices by both NIH count and visually assessed (manual) count respectively were 12.7% +/- 9.9% (mean +/- standard deviation) and 12.6% +/- 9.9% in all gliomas (n = 50), 2.9% +/- 0.6% and 2.3% +/- 0.6% in grade I and II astrocytomas (n = 9), 10.7% +/- 8.9% and 11.1% +/- 9.0% in grade III gliomas (n = 17), 16.1% +/- 9.1% and 16.3% +/- 9.1% in glioblastoma multiformes (n = 20), 26.0% +/- 4.9% and 24.5% +/- 2.6% in other glial tumors (n = 4). These paired values were assumed to be identical, since the p value obtained by paired t-test in all gliomas was 0.905. We conclude that the MIB-1 staining index measured by NIH Image is reliable and universal.

Antigens, Nuclear↗
PubMed2006

Assessment of dynamic image analysis as a surrogate dissolution test for a coated multiparticulate product.

Dynamic image analysis (DIA) was used to measure particle diameter (D50) of in-process samples removed during fluid bed coating. A single, rapid measurement gave D50 to within 4 mum. Samples removed at intervals of 2% weight gain were readily distinguishable by DIA and by their drug release profiles. Drug release was related to D50. DIA was assessed as a surrogate dissolution test with considerable potential. Current limitations of the approach were presented.

Coated Materials, Biocompatible↗
PubMed2003

Automated image analysis of disturbed cytoarchitecture in Brodmann area 10 in schizophrenia.

To detect cytoarchitectonic abnormalities in the Brodmann area 10 (BA10) of schizophrenic patients, we applied a newly modified variant of the gray-level index (GLI) method as fully automated image analysis method providing cytoarchitectonic profiles of the whole cortex as a scanning tool. Microscopic images of silver-stained sections of 20 schizophrenic brains compared to 20 control brains were automatically scanned and binarized at an adaptive threshold. In 30 measuring fields through the whole cortical depth, the dependent measure of gray-level index (GLI) as the area-percentage covered by perikarya in a measuring field was obtained providing a cytoarchitectonic profile. GLI is an estimate of the volume density of perikarya. A statistical analysis of mean GLI values was performed for six compartments, separately, approximately corresponding to cortical layers. Results revealed significant GLI reductions in schizophrenic brains in all six compartments suggesting either a decreased perikarya fraction or an increased neuropil fraction. The described automated image analysis method providing cytoarchitectonic profiles can be applied as a fast and observer-independent scanning tool to detect cytoarchitectonic abnormalities in multiple brain regions.

Adult↗
PubMed1991

Quantitative fluorescence image analysis of deoxyribonucleic acid ploidy in urine from normal children.

Quantitative fluorescence image analysis incorporates the 2 diagnostic techniques of cytological analysis with quantitation of deoxyribonucleic acid (DNA). Exfoliated urinary cells are ideal for analysis by this method, which allows the identification of "rare event" abnormal cells. We evaluated the urine from 50 children who had undergone cystoscopy or were catheterized for other reasons. The urine was free of infection by urinalysis. Cytological analysis demonstrated normal or atypical cells in all patients. Of the patients 1 (2%) had greater than 2 of 500 cells analyzed with greater than 5C DNA and 4 (8%) had greater than 2 of 500 cells with greater than 5C double stranded nucleic acid. These data suggest that it may be "normal" for urine to contain "rare event" abnormal cells. The significance of this finding is unclear at present.

Adolescent↗
PubMed1990

A new automated method of image analysis: comparison of ciliary and flagellar beats.

A new automated method of image analysis of sperm flagellar (human) and cilia (Dunaliella) bends is developed. This method permits an automatic determination of the line characterizing the flagellum. Two dynamic parameters are measured: the wave propagation velocity and the wave curvature radius. The data reveal similar patterns in the propagation of the principal and reverse waves between flagelated and ciliated cells. Conversely, differences are seen in principal wave curvature due perhaps to the presence of periaxonemal structures in the flagellum, absent in cilium. The identical patterns of reverse wave curvaturei in both systems may be linked to axonemal limitations.

Cilia↗
PubMed1995

Programmed cell death in sympathetic neurons: a study by two-dimensional polyacrylamide gel electrophoresis using computer image analysis.

The technique of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) coupled with computer image analysis was used in this study to examine changes in protein expression occurring during the onset of programmed cell death (PCD) in rat sympathetic neurons following withdrawal of nerve growth factor (NGF). Sympathetic neurons from superior cervical ganglia of postnatal day-one Wistar rats were cultured in the presence of NGF for 24 h and then either maintained in the presence of NGF or deprived of NGF for a period of 8 h. To label the proteins being synthesised, neurons were cultured in the presence of L-[35S]methionine for a further 2 h under the same conditions but with 3% of the normal methionine concentration. Neuronal proteins were then analysed by 2-D PAGE using immobilised pH gradient (IPG) gel strips in the first dimension. For the second dimension a custom-built electrophoresis system capable of running multiple sodium dodecyl sulfate (SDS)-PAGE slab gels in a vertical configuration, with good temperature control (+/- 0.7 degrees C) was used and is described in this paper. Proteins resolved on the dried gels were visualised using storage phosphor technology and the digitised images subjected to rigorous analysis using the QUEST II software system. Seventeen proteins whose relative synthesis decreased and four proteins that increased upon NGF withdrawal were located and are documented.

Animals↗
PubMed1989

Profile matching and profile subtraction: application of computer-based image analysis system for two-dimensional electrophoresis gels.

The microcomputer-based image analysis system IB-1000 (developed by Indiana Biotech, Highland, IN) for two-dimensional electrophoresis gels has been described previously (9). It allows the user to compare protein spots between two profiles and identify those spots that are commonly shared in both profiles. This report describes two applications of the system's global comparison routine-profile matching and profile subtraction. This application is able to subtract commonly shared spots from one profile, creating a new profile made up by the unmatched spots in the other profile. These applications can be employed in a large variety of research projects.

Animals↗
PubMed1993

[Optic disc measurements for cup depth with computerized image analysis in normal subjects and case of ocular hypertension and glaucoma].

Computerized image analysis was performed in 46 normals subjects and in 47 cases of ocular hypertension and 48 cases of early glaucoma for optic disc cup depth and optic disc parameters (rim area, cup area, cup volume and cup/disc ratio). The optic disc cup depth was 369.6 +/- 18.2 microns (M +/- SEM) in normal subject, 538.3 +/- 24.0 microns in ocular hypertension cases, 675.0 +/- 24.7 microns in glaucoma cases. The cup depth was significantly different among the three groups. The quotient of horizontal to vertical cup/disc ratio was also significantly different among the groups (1.84 +/- 0.17 in normal subjects, 1.28 +/- 0.05 in ocular hypertension cases, and 1.120 +/- 0.03 in glaucoma cases.) These results demonstrate that the optic disc cup enlarges three-dimensionally in early glaucoma.

Adult↗
PubMed2004

Use of multispectral magnetic resonance imaging analysis to quantify erosive changes in the hands of patients with rheumatoid arthritis: short-term and long-term longitudinal studies.

OBJECTIVE: Magnetic resonance imaging (MRI) has been shown to be more sensitive than radiography for detecting bone erosions in rheumatoid arthritis (RA). Semiquantitative scoring based on visual image assessment has been introduced. However, there is considerable interest in true quantitative measures, particularly in the context of clinical trials designed to show differences between treatment groups. This study was undertaken to investigate the use of a new quantitative approach, multispectral (MS) image analysis, for assessing erosive change. METHODS: T1-weighted spin-echo (SE) and fat-suppressed gradient-echo (GE) sequences of metacarpophalangeal joints of the dominant hand were acquired at various time points throughout a 2-year period. MS analysis was applied to all images, resulting in segmentation into a generalized bone and a soft tissue class. Voxel changes from one to the other class identified apparent bone lesion volume change (Delta BLV). MR images were also visually scored for erosions (E score). All analyses were performed separately, on a per-joint basis, for short-term and long-term data sets. RESULTS: Analysis of variance with adjustment for individual effect revealed similar results in the short-term and the long-term studies, using either GE or SE images for visual assessment. Patients with an increase in E score on visual assessment had a significantly higher Delta BLV than those without. CONCLUSION: Temporal MS analysis of MRIs can be used to detect and quantify erosive changes in RA. This semiautomated method may be useful for demonstrating differences between treatment groups in clinical trials.

Adult↗
PubMed1997

Dynamic MR Imaging and Tumor Angiogenesis in DMBA-Induced Rat Breast Cancer: Three Dimensional (3D) Reconstructed Image Analysis of Tumor Microvessels by Confocal Laser Scanning Microscopy.

We investigated the correlation between dynamic magnetic resonance imaging (MRI) findings in breast cancer and tumor angiogenesis in a dimethylbenz(a)anthracene(DMBA)-induced rat breast cancer model. In this study, we clearly demonstrated the three-dimensional (3D) architecture of tumor microvessel networks(MN)by confocal laser scanning microscopy (CLSM)and also investigated the hyperpermeability of tumor microvessels. Dynamic MRI findings were closely related to tumor angiogenesis. Three-dimensional reconstructed image analysis by CLSM revealed that the depicted images were dependent on microvessel density as well as microvessel permeability. It should be emphasized that dynamic MRI may have the potential to evaluate the tumor angiogenic activity in human breast carcinoma.

Journal Article↗
PubMed2003

Real-time augmentation of USDA yield grade application to beef carcasses using video image analysis.

In two phases, this study assessed the ability of two video image analysis (VIA) instruments, VIASCAN and Computer Vision System (CVS), to augment assignment of yield grades (YG) to beef carcasses to 0.1 of a YG at commercial packing plant speeds and to test cutout prediction accuracy of a YG augmentation system that used a prototype augmentation touchpanel grading display (designed to operate commercially in real-time). In Phase I, beef carcasses (n = 505) were circulated twice at commercial chain speeds (340 carcasses per hour) by 12 on-line USDA graders. During the first pass, on-line graders assigned a whole-number YG and a quality grade (QG) to carcasses as they would normally. During the second pass, on-line graders assigned only adjusted preliminary yield grades (APYG) and QG to carcasses, whereas the two VIA instruments measured the longissimus muscle area (LMA) of each carcass. Kidney, pelvic, and heart fat (KPH) was removed and weighed to allow computation of actual KPH percentage. Those traits were compared to the expert YG and expert YG factors. On-line USDA graders' APYG were closely related (r = 0.83) to expert APYG. Instrument-measured LMA were closely related (r = 0.88 and 0.94; mean absolute error = 0.3 and 0.2 YG units, for VIASCAN and CVS, respectively) to expert LMA. When YG were augmented using instrument-measured LMA and computed either including or neglecting actual KPH percentage, YG were closely related (r = 0.93 and 0.92, mean absolute error = 0.32 and 0.40 YG units, respectively, using VIASCAN-measured LMA; r = 0.95 and 0.94, mean absolute error = 0.24 and 0.34 YG units, respectively, using CVS-measured LMA) to expert YG. In Phase II, augmented YG were assigned (0.1 of a YG) to beef carcasses (n = 290) at commercial chain speeds using VIASCAN and CVS to determine LMA, whereas APYG and QG were determined by online graders via a touch-panel display. On-line grader YG (whole-number), expert grader YG (to the nearest 0.1 of a YG), and VIASCAN- and CVS-augmented YG (to the nearest 0.1 of a YG) accounted for 55, 71, 60, and 63% of the variation in fabricated yields of closely trimmed subprimals, respectively, suggesting that VIA systems can operate at current plant speeds and effectively augment official USDA application of YG to beef carcasses.

Animals↗
PubMed1987

DNA cytometry and cytology by quantitative fluorescence image analysis in symptomatic bladder cancer patients.

A semi-automated quantitative fluorescence image analysis (QFIA) technique was developed with the Leitz TAS-Plus to detect bladder cancer using hyperploidy in urinary cells. Absolute nuclear fluorescence intensity (ANFI) (emission at 540 nm with excitation at 436 nm) of individual acridine-orange-stained cells was quantitated using (1) QFIA and (2) simple filter microspectrofluorophotometry (SFM). Both methods employed an internal phosphor particle standard which, when once calibrated against the DNA content of normal cells, obviates the necessity of routinely calibrating against normal cells in each sample. Results of SFM and QFIA were compared with routine Papanicolaou (Pap) cytopathology, using histopathology as the diagnostic standard in 272 samples from 67 symptomatic patients. The sensitivities for detecting low-grade transitional-cell carcinoma were 86% for SFM, 76% for QFIA, and 33% for Pap cytology. QFIA and SFM were significantly more sensitive at detecting bladder cancer than was Pap (0.01 greater than p greater than 0.001). Comparison of sensitivity obtained with bladder washings and urine samples showed that noninvasively obtained urines can be used. ANFI also detected recurrent and precancerous bladder lesions and kidney, ureter, and prostate lesions. This approach may prove generally useful in quantifying biochemical and immunological probes and should be broadly applicable as a research tool for studying the relationship of biochemical markers in the pathogenesis of disease and as a test for cancer control.

Carcinoma, Transitional Cell↗