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PubMed1991

DNA measurement by image analysis of paraffin-embedded breast carcinoma tissue. A comparative investigation.

Measurement of cellular DNA content may provide useful prognostic information in several human neoplasms. The DNA content by image analysis of fresh tissue has been compared with flow cytometry with good correlation, but the use of paraffin-embedded tissue for image analysis has not been studied widely. This study reports the DNA content of 54 breast carcinomas and compares the results of image analysis of paraffin-embedded tissue and results of image analysis and flow cytometry of corresponding fresh tumors. Image analysis of paraffin blocks and fresh tumors showed comparable results in 51 tumors (94%), whereas 47 tumors (87%) were similar by all three methods. The DNA indices from image analysis of fresh and paraffin-embedded tumors showed significant correlation by linear regression analysis (r = 0.96; P less than 0.001). Discordances between image analysis of fresh and paraffin-embedded tumors are the result of technical problems, such as staining and tissue preservation. Discordances between image analysis and flow cytometry reflect the advantages and pitfalls of the two techniques. These data suggest that image analysis of paraffin-embedded tissue is a viable technique that will permit the performance of retrospective studies with long-term follow-up data for the evaluation of the prognostic significance of DNA content.

Breast Neoplasms↗
PubMed1996

Cortical and cancellous bone in the human femoral neck: evaluation of an interactive image analysis system.

An interactive image analysis package was developed to examine whole cross-sections from the femoral neck. The package quantifies cortical width (Ct.Wi), cortical porosity (Ct.Po), and proportions of cortical, cancellous bone as a percentage of bone plus marrow area. Segmental analysis was used to quantify circumferential variations in bone distribution within the femoral cross-section. To evaluate reproducibility of data four independent operators analyzed previously prepared femoral neck sections from a 2000 BC population. Differences in total and circumferential distributions of cortical and cancellous bone with respect to gender and age of samples were demonstrated. Reproducibility was assessed using coefficients of variation (CV). Analysis of sections using a variable magnification, giving largest possible image size, rather than a set magnification reduced variation between operators for all measurements. Use of a calculated threshold significantly decreased variation between operators for the proportions of cortical and cancellous bone (p < or = 0.026). Dividing the image into 8 rather than 16 segments also improved reproducibility. There was little agreement between operators in the determination of cortical porosity. The mean CV for the other quantitative indices such as cortical width and proportions of cortical and cancellous bone ranged from 4.87% to 13.52%. The genders showed similar patterns in circumferential distribution of bone. Cortical width was significantly greater in the inferior region compared to the other areas, whereas percent cortical bone was lowest at the superior region. The center of mass (COM) for the younger age group was located anteriorly, whereas in the older samples the COM was located posteriorly of the center of area (p = 0.041). Basic data relating to cortical and cancellous bone of acceptable reproducibility in comparison with current standards in iliac histomorphometry can now be provided at modest cost in operator time and resources.

Adult↗
PubMed1990

Quantitative fluorescence image analysis in bladder cancer screening.

Quantitative fluorescence image analysis (QFIA) cytology combines image analysis to measure DNA with visual cytology for bladder cancer detection. QFIA sensitivity is 76% to 81% and 95% to 100% for low- and high-grade tumors respectively, with 94% specificity in asymptomatic controls. QFIA screening of 504 persons within a beta-naphthylamine exposed cohort found DNA hyperploidy correlated with the duration of carcinogenic exposure and smoking history; marker prevalence was 23% for exposed workers who smoked and 2% for nonexposed nonsmokers. In prospective animal studies, QFIA was useful in monitoring carcinogenesis and chemoprevention with retinoids. Current QFIA research focuses on measurements of oncogenes, growth factors and their receptors, cytoskeleton, and tumor-associated antigens to improve sensitivity and specificity to low-grade tumors and to identify premalignant conditions. Profiles of biochemical and immunological markers on single cells may further assist in the study of high-risk cohorts and individual risk assessment.

Biomarkers, Tumor↗
PubMed2005

Retinal image analysis: concepts, applications and potential.

As digital imaging and computing power increasingly develop, so too does the potential to use these technologies in ophthalmology. Image processing, analysis and computer vision techniques are increasing in prominence in all fields of medical science, and are especially pertinent to modern ophthalmology, as it is heavily dependent on visually oriented signs. The retinal microvasculature is unique in that it is the only part of the human circulation that can be directly visualised non-invasively in vivo, readily photographed and subject to digital image analysis. Exciting developments in image processing relevant to ophthalmology over the past 15 years includes the progress being made towards developing automated diagnostic systems for conditions, such as diabetic retinopathy, age-related macular degeneration and retinopathy of prematurity. These diagnostic systems offer the potential to be used in large-scale screening programs, with the potential for significant resource savings, as well as being free from observer bias and fatigue. In addition, quantitative measurements of retinal vascular topography using digital image analysis from retinal photography have been used as research tools to better understand the relationship between the retinal microvasculature and cardiovascular disease. Furthermore, advances in electronic media transmission increase the relevance of using image processing in 'teleophthalmology' as an aid in clinical decision-making, with particular relevance to large rural-based communities. In this review, we outline the principles upon which retinal digital image analysis is based. We discuss current techniques used to automatically detect landmark features of the fundus, such as the optic disc, fovea and blood vessels. We review the use of image analysis in the automated diagnosis of pathology (with particular reference to diabetic retinopathy). We also review its role in defining and performing quantitative measurements of vascular topography, how these entities are based on 'optimisation' principles and how they have helped to describe the relationship between systemic cardiovascular disease and retinal vascular changes. We also review the potential future use of fundal image analysis in telemedicine.

Animals↗
PubMed1998

Multivariate Image Analysis of Magnetic Resonance Images with the Direct Exponential Curve Resolution Algorithm (DECRA).

Antalek and Windig recently presented a fast method to resolve a series of NMR mixture spectra, where the contribution of the components varies with a decaying exponential [B. Antalek and W. Windig, J. Am. Chem. Soc. 118, 10,331-10,332 (1996); W. Windig and B. Antalek, Chemom. Intell. Lab. Syst. 37, 241-254 (1997)]. The method was called DECRA (direct exponential curve resolution algorithm). In this paper DECRA will be applied to two series of magnetic resonance images. The signal of one series is based upon T2 relaxation, and the other is based upon T1 relaxation. In order to evaluate the technique, the magnetic resonance images of a phantom where used. A transformation is introduced to enable the application of DECRA to a T1 series of magnetic resonance images. A separate paper in this issue will describe the application of the techniques to magnetic resonance images of the human brain. Copyright 1998 Academic Press.

Journal Article↗
PubMed2004

Digital image analysis for diagnosis of cutaneous melanoma. Development of a highly effective computer algorithm based on analysis of 837 melanocytic lesions.

BACKGROUND: Digital image analysis has been introduced into the diagnosis of skin lesions based on dermoscopic pictures. OBJECTIVES: To develop a computer algorithm for the diagnosis of melanocytic lesions and to compare its diagnostic accuracy with the results of established dermoscopic classification rules. METHODS: In the Department of Dermatology, University of Tuebingen, Germany, 837 melanocytic skin lesions were prospectively imaged by a dermoscopy video system in consecutive patients. Of these lesions, 269 were excised and examined by histopathology: 84 were classified as cutaneous melanomas and 185 as benign melanocytic naevi. The remaining 568 lesions were diagnosed by dermoscopy as benign. Digital image analysis was performed in all 837 benign and malignant melanocytic lesions using 64 different analytical parameters. RESULTS: For lesions imaged completely (diameter < or = 12 mm), three analytical parameters were found to distinguish clearly between benign and malignant lesions, while in incompletely imaged lesions six parameters enabled differentiation. Based on the respective parameters and logistic regression analysis, a diagnostic computer algorithm for melanocytic lesions was developed. Its diagnostic accuracy was 82% for completely imaged and 84% for partially imaged lesions. All 837 melanocytic lesions were classified by established dermoscopic algorithms and the diagnostic accuracy was found to be in the same range (ABCD rule 78%, Menzies' score 83%, seven-point checklist 88%, and seven features for melanoma 81%). CONCLUSIONS: A diagnostic algorithm for digital image analysis of melanocytic lesions can achieve the same range of diagnostic accuracy as the application of dermoscopic classification rules by experts. The present diagnostic algorithm, however, still requires a medical expert who is qualified to recognize cutaneous lesions as being of melanocytic origin.

Algorithms↗
PubMed1998

Morphometric analysis of LPS-stimulated human monocytes by computer-assisted image analysis.

This report describes the results of applying the computer-assisted image analysis system for the measurement of some cytological parameters of LPS-stimulated and nonstimulated human monocytes. The experiments were carried out by means of the digital cell image analysis of haematoxilyn stained monocytes. Five different parameters describing the morphology of monocytes and their nuclei were selected to quantitate the differences between control and activated cells area, perimeter, elongation, dispersion, and extension of images of cell projections. The results suggest that all of the analysed parameters can be used to discriminate stimulated from nonstimulated monocytes which permits detailed monitoring of the changes in cell morphology during monocyte activation.

Biometry↗
PubMed2004

Mathematical analysis of tooth and restoration contour using image analysis.

OBJECTIVES: The aim of this study was to develop a methodology for comparison of the contour of artificial crowns in the mid bucco-lingual plane with their equivalent natural teeth on the opposing side of the same arch (antimeres) using a novel application of image analysis software. The objective was to determine whether artificial crowns were overcontoured. METHODS: Specimens consisted of thin sections of silicone putty impressions of the buccal and lingual surfaces of 55 full crown restorations and their natural antimeric teeth. A thin slice of the putty was obtained in the mid-tooth bucco-lingual plane and a digital image was captured and this was analysed to produce a data set (x, y) representing the curvature of the tooth surface. Further analysis was performed in order to describe the profile in optimum mathematical terms. RESULTS: The curves were best represented by three equations: y = a + bx(0.5), ln(y) = a + bx2, and y2 = a + bx. In all equations parameter (b), which expresses the contour curvature, was used as a deciding factor in comparing the degree of contour of the crown restorations with their natural antimeres. Most artificial crowns were found to be either similarly or undercontoured when compared with their natural antimeres. When overcontouring was present in the artificial crowns this tended to occur on the lingual aspects of anterior and posterior crowns. SIGNIFICANCE: Simplifying tooth contour into a mathematical model can be useful in determining whether restorations are overcontoured. Clinically, particular attention should be directed towards the lingual aspects of restorations which were more likely to be overcontoured.

Crowns↗
PubMed2006

Detailed plaque texture analysis as the alternate method of ultrasound image analysis in predicting the risk of intraoperative microembolism and perioperative complications.

BACKGROUND: The aim of the study was to assess the value of an alternative method of carotid plaque ultrasound image analysis in relation to the perioperative complications and the main risk factor: the microembolism (ME). MATERIAL AND METHODS: 96 plaques were evaluated following carotid endarterectomy. Preoperatively, each plaque was screened by ultrasound and assessed by means of 2 computer assisted methods. All patients were evaluated for ME (measured as hits) intraoperatively. The removed plaques were assessed visually (intraoperative assessement) and histologically. A number of risk factors were included as a final outcome event for the purpose of multivariate regression analysis. RESULTS: Detailed plaque texture analysis (DPTA) predicts best the risk of perioperative complications and ME (p = 0.029 and p = 0.028 respectively). The results of the standard gray-scale median (GSM) analysis did not reach the statistical significance (p > 0.1). The predictive value of the model (ROC) was 0.88. The multivariate model for ME revealed that from the level of > 5 HITS, a rapid increase in the risk of perioperative complications (rise of 5% by every 1 hit) is seen and correlates well with the DPTA. ROC was 0.77. A direct correlation between the DPTA and perioperative ME was shown. CONCLUSIONS: DPTA analysis of a carotid plaque is more predictive of the likelihood of microembolism than the GSM analysis. There is a direct correlation between the perioperative ME and plaque morphology, as assessed by DPTA. This supports the need for further refinements in noninvasive analysis of carotid plaques.

Aged↗
PubMed1997

Cytoplasmic microtubules in two different mouse melanoma cell lines: a qualitative and quantitative analysis using confocal laser scanning microscopy and computer-assisted image analysis.

The microtubular system as one part of the cellular cytoskeleton is not only necessary for mitotic activity of malignant cells but also for invading neighboring tissues and for the formation of distant metastases. In the present study, the amount and distribution of tubulin in two murine melanoma cell lines (K1735-M2: high metastatic clone; K1735-c116: low metastatic clone) were determined quantitatively using an indirect immunofluorescence technique, confocal laser scanning microscopy (CLSM) and computer-assisted image analysis. Additionally, qualitative and quantitative changes after application of the microtubule-inhibitor nocodazole were investigated. Quantitative analysis showed a significant difference between the high and low metastatic cell line for the parameter TEXTURE, indicating a finer structured network within the high metastatic cells. After treatment with nocodazole the parameters TEXTURE and DENSITY were reduced, suggesting a decrease of assembled tubulin and a less delicate structure of the remaining microtubules. Our study shows that CLSM combined with computer-assisted image analysis provides a new method to examine quantitative variations of the cytoskeleton possibly related to cell function.

Animals↗
PubMed1993

Comparison of image analysis and flow cytometric measurements of DNA content of canine transitional cell carcinomas.

The DNA content of neoplasms is generally determined by flow cytometry, but quantitative microscopic image analysis is an alternative technique for DNA quantification. To compare these two methods, the DNA content of 31 paraffin-embedded canine transitional cell carcinomas was measured by flow cytometry and image analysis. Interpretable data were available for 26 samples by flow cytometry and 27 samples by image analysis. For 23 neoplasms with interpretable data by both methods, a good correlation (r = .80, P < .001) was obtained between the DNA indices determined by flow cytometry and image analysis. Concordance of DNA ploidy classification was reached in 21 samples; however, for 4 samples an aneuploid cell population, usually tetraploid, was identified by image analysis and not by flow cytometry. Two samples also had aneuploid peaks by flow cytometry and not by image analysis. Although a good correlation was seen between the measurement of DNA content of paraffin-embedded canine tissue by image analysis and flow cytometry, this study did demonstrate that aneuploid cell populations can be missed by both methods and that image analysis was better than flow cytometry in the detection of aneuploid cell populations, particularly tetraploid ones, in samples with excessive cellular debris.

Animals↗
PubMed2001

Automated image analysis for array hybridization experiments.

MOTIVATION: Image analysis is a major part of data evaluation for array hybridization experiments in molecular biology. The program presented here is designed to analyze automatically images from hybridization experiments with various arrangements: different kinds of probes (oligonucleotides or complex probes), different supports (nylon filters or glass slides), different labeling of probes (radioactively or fluorescently). The program is currently applied to oligonucleotide fingerprinting projects and complex hybridizations. The only precondition for the use of the program is that the targets are arrayed in a grid, which can be approximately transformed to an orthogonal equidistant grid by a projective mapping. RESULTS: We demonstrate that our program can cope with the following problems: global distortion of the grid, missing of grid nodes, local deviation of the spot from its specified grid position. This is checked by different quality measures. The image analysis of oligonucleotide fingerprint experiments on an entire genetic library is used, in clustering procedures, to group related clones together. The results show that the program yields automatically generated high quality input data for follow up analysis such as clustering procedures. AVAILABILITY: The executable files will be available upon request for academics.

Algorithms↗
PubMed1991

Diagnostic value of DNA analysis in effusions by flow cytometry and image analysis. A prospective study on 102 patients as compared with cytologic examination.

One hundred twenty-six effusion samples from 102 patients were examined by cytology and flow cytometry (FCM). Overall, there was an 84% correlation between cytologic and FCM results. Of the 36 malignant cases determined by cytologic examination, FCM revealed an aneuploid peak in 20 (56%). Image analysis (IA) performed on the malignant cytologic cases with a diploid flow pattern detected two additional aneuploid peaks. In addition, FCM indicated three aneuploid cases in which cytologic characteristics were initially interpreted as benign (false negative). Aneuploidy was therefore detected in 64% of the malignant effusion specimens by FCM and IA. Twenty-three of the total of 24 aneuploid cases detected by FCM were associated with malignancy (predictive value = 96%). The one nonmalignant case was that of hemorrhagic pancreatitis with infected pseudocyst. FCM is an excellent tool when moderate to large numbers of tumor cells are present, whereas use of IA is advantageous for specimens containing smaller numbers of malignant cells because these can be directly analyzed. When an aneuploid peak is present, a diagnosis of malignancy must be suspected, and, if the initial cytologic screen is negative, a critical review of the cytology slides is justified. In those cases with an equivocal atypical cytology report and an abnormal cytometric histogram, additional investigation is warranted. In some malignancies the tumor cells will be diploid (in this study 36%) and neither FCM nor IA will add to tumor detection, leaving cytologic examination as the definitive technique.

Adult↗
PubMed1992

Predicting outcome for patients with node negative breast cancer: a comparative study of the value of flow cytometry and cell image analysis for determination of DNA ploidy.

This study was aimed at determining whether tumour DNA content measured by cell image analysis could provide additional prognostic information when compared to that provided by flow cytometry. Sections cut from paraffin blocks of tumours from 101 patients with node negative breast cancer were analysed by both methods and the results related to other prognostic variables and to patient relapse and overall survival. DNA ploidy measured by flow cytometry classified 46 tumours as diploid and 55 as aneuploid, whereas by cell image analysis 30 were diploid and 71 aneuploid (P less than 0.002). There were 20 tumours with discrepancies between the two methods; 18 of these were tumours with only one peak in flow analysis, but determined to be aneuploid with image analysis. DNA content as measured by both methods was significant for predicting relapse and survival by log-rank test, as were tumour histological grade, c-erbB-2 expression and tumour size. Multivariate analysis showed DNA ploidy measured by flow cytometry to be the only variable of independent significance (P less than 0.02) for both relapse and overall survival. Compared with cell image analysis, flow cytometry demonstrated a significantly higher proportion of diploid tumours, which may be related to differences in the internal standards applied to each method. We suggest that cell image analysis techniques can provide more sensitive information on the DNA content of tumour cells by direct measurement of nuclear DNA density of both normal lymphocytes and tumour cells in the same section. However, although image analysis appears to be more sensitive than flow cytometry in detecting DNA aneuploidy, the image technique appears to lack the specificity of flow cytometry in correlation with clinical outcome.

Adult↗
PubMed1986

Estrogen receptor immunocytochemical assay (ER-ICA): computerized image analysis system, immunoelectron microscopy, and comparisons with estradiol binding assays in 115 breast carcinomas.

An estrogen receptor (ER) immunocytochemical assay (ER-ICA) was applied to 115 malignant breast carcinomas and the results were compared to those of steroid binding assays performed on cytosol extracts of the same tumors. Immunoperoxidase (peroxidase-antiperoxidase) staining was performed on frozen sections using rat monoclonal antibody to estrogen receptor H222SP gamma. A preembedding method was used for the immunoelectron microscopy study. A semiquantitative analysis and a computerized image analysis system (SAMBA 200 TITN) were used to evaluate the positive ER immunostaining. Positive immunostaining (81 of 115) was always located in the nucleus of tumor cells and of normal cells in adjacent breast tissue. The immunostaining pattern differed from one tumor to another, due to variations in either the intensity or the percentage of positive cells. When immunohistochemical staining was correlated to biochemical assay, there was an 88% correlation, and staining intensity and percentage of positive cells significantly increased (P less than 0.01) with cytosolic ER levels and were independent of cellularity. These results indicated that ER-ICA is to date the most reliable histochemical method for ER detection and correlated in 88% of the cases with ER biochemical assay; ER-ICA constitutes a method particularly valuable to screen ER negative tumors on condition that tumor fragment quality (sampling and storage) is perfectly controlled; ER-ICA provides additional information for heterogeneous ER distribution within tumors; ER-ICA as a qualitative method is unable to replace the quantitative ER determination obtained with biochemical assay although the computerized system (SAMBA 200) for image analysis of microscopic preparations constitutes a valuable improvement of immunostaining analysis; and ER-ICA based on ER antigenic site detection is complementary to biochemical assay based on ER functional site determination.

Antibodies, Monoclonal↗
PubMed1988

Detection and quantification of microorganisms in a heterogeneous foodstuff by image analysis.

A relatively inexpensive image analysis system has been developed to semi-automate the detection and quantification of microbial growth in sections of food. A system based on an IBM PC compatible, with a frame store card, was programmed to scan Gram-stained sections using a motorized stage. Each field of view was thresholded after subtraction of a background image and the area between two thresholds measured. In the food studied it was found that, by using a size limit, it was possible to reduce the number of fields that needed to be examined by a microscopist to approximately 3% of those scanned. Visual examination was still required to distinguish bacterial cells from other stained objects which occasionally occur.

Algorithms↗
PubMed2005

Reduced hippocampal metabolism in MCI and AD: automated FDG-PET image analysis.

BACKGROUND: To facilitate image analysis, most recent 2-[18F]fluoro-2-deoxy-d-glucose PET (FDG-PET) studies of glucose metabolism (MRglc) have used automated voxel-based analysis (VBA) procedures but paradoxically none reports hippocampus MRglc reductions in mild cognitive impairment (MCI) or Alzheimer disease (AD). Only a few studies, those using regions of interest (ROIs), report hippocampal reductions. The authors created an automated and anatomically valid mask technique to sample the hippocampus on PET (HipMask). METHODS: Hippocampal ROIs drawn on the MRI of 48 subjects (20 healthy elderly [NL], 16 MCI, and 12 AD) were used to develop the HipMask. The HipMask technique was applied in an FDG-PET study of NL (n = 11), MCI (n = 13), and AD (n = 12), and compared to both MRI-guided ROIs and VBA methods. RESULTS: HipMask and ROI hippocampal sampling produced significant and equivalent MRglc reductions for contrasts between MCI and AD relative to NL. The VBA showed typical cortical effects but failed to show hippocampal MRglc reductions in either clinical group. Hippocampal MRglc was the only discriminator of NL vs MCI (78% accuracy) and added to the cortical MRglc in classifying NL vs AD and MCI vs AD. CONCLUSIONS: The new HipMask technique provides accurate and rapid assessment of the hippocampus on PET without the use of regions of interest. Hippocampal glucose metabolism reductions are found in both mild cognitive impairment and Alzheimer disease and contribute to their diagnostic classification. These results suggest re-examination of prior voxel-based analysis 2-[18F]fluoro-2-deoxy-d-glucose PET studies that failed to report hippocampal effects.

Aged↗