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PubMed2003

Cardiac arrest: long-term cognitive and imaging analysis.

BACKGROUND: Neurological and cognitive sequelae resulting from cardiac arrest (CA), despite their potential personal and social impact, are usually not considered as major outcome measures in long-term analysis of survivors. The aim of this study is to analyze the contribution of neuropsychological testing and cerebral imaging to the development of a long-term classification of neurological impairment. PATIENTS AND METHODS: A total of 19 patients admitted over a 3 years period in an eight-bed intensive care unit of a tertiary care hospital with a diagnosis of CA were alive and attended a 6-month follow-up consultation. Eleven of these patients agreed to participate in this study carried out between 1 and 3 years after CA. Patients were classified using the Cerebral Performance Categories (CPC), neurological examination, detailed cognitive testing and computerized tomography (CT) scan with qualitative and quantitative imaging analysis. RESULTS: Six of the 11 patients had good cerebral performance. Verbal and visuo-spatial short-term memory scores were associated with CPC. All patients with at least moderate cerebral disability had abnormal verbal memory test results compared with only one survivor with CPC 1; visuo-spatial short-term memory was abnormal in four moderately affected survivors and normal in those with CPC 1. The bicaudate ratio evaluated in the CT scan was correlated with the verbal memory score while the III ventricle diameter correlated with the executive functions score, suggesting involvement of different brain areas in these functions. CONCLUSIONS: Neuropsychological and CT scan measurements are proxy measures of long-term impairment of CA survivors, providing a dichotomized global evaluation of CA survivors in close agreement with CPC.

Adult↗
PubMed2006

A novel two-dimensional echocardiographic image analysis system using artificial intelligence-learned pattern recognition for rapid automated ejection fraction.

OBJECTIVES: We sought to test the hypothesis that a novel 2-dimensional echocardiographic image analysis system using artificial intelligence-learned pattern recognition can rapidly and reproducibly calculate ejection fraction (EF). BACKGROUND: Echocardiographic EF by manual tracing is time consuming, and visual assessment is inherently subjective. METHODS: We studied 218 patients (72 female), including 165 with abnormal left ventricular (LV) function. Auto EF incorporated a database trained on >10,000 human EF tracings to automatically locate and track the LV endocardium from routine grayscale digital cineloops and calculate EF in 15 s. Auto EF results were independently compared with manually traced biplane Simpson's rule, visual EF, and magnetic resonance imaging (MRI) in a subset. RESULTS: Auto EF was possible in 200 (92%) of consecutive patients, of which 77% were completely automated and 23% required manual editing. Auto EF correlated well with manual EF (r = 0.98; 6% limits of agreement) and required less time per patient (48 +/- 26 s vs. 102 +/- 21 s; p < 0.01). Auto EF correlated well with visual EF by expert readers (r = 0.96; p < 0.001), but interobserver variability was greater (3.4 +/- 2.9% vs. 9.8 +/- 5.7%, respectively; p < 0.001). Visual EF was less accurate by novice readers (r = 0.82; 19% limits of agreement) and improved with trainee-operated Auto EF (r = 0.96; 7% limits of agreement). Auto EF also correlated with MRI EF (n = 21) (r = 0.95; 12% limits of agreement), but underestimated absolute volumes (r = 0.95; bias of -36 +/- 27 ml overall). CONCLUSIONS: Auto EF can automatically calculate EF similarly to results by manual biplane Simpson's rule and MRI, with less variability than visual EF, and has clinical potential.

Aged↗
PubMed2003

Radiographic alveolar bone loss in untreated Taiwan Chinese subjects with adult periodontitis measured by the digital scanning radiographic image analysis method.

OBJECTIVES: To determine differences in radiographic alveolar bone loss (RABL) by age group, gender and tooth type in subjects with adult periodontitis using the digital scanning radiographic image analysis (DSRIA) method. METHODS: A total of 4262 teeth were examined for RABL in 178 individuals (96 males and 82 females). Mesial and distal sites were determined by the DSRIA method following scanning of periapical radiographs and using the Microstation 95 image software. RESULTS: Linear assessment of RABL using DSRIA revealed the following results. Mean bone loss of maxillary and mandibular anterior teeth was significantly higher (P<0.001 and P<0.01, respectively) in males compared with females using a two-sample t-test. The highest values of mean RABL occurred most commonly in the maxillary first molars (53.8% and 51.4% for females and males, respectively) and the mandibular central incisors (50.4% and 41.5% for males and females, respectively). Mean RABL was greater in males than in females for both the mandibular and maxillary arches, with the exception of molar sites. CONCLUSIONS: Maxillary first molars and mandibular incisors are the highest risk sites. Moreover, greater loss occurs at the molar site in females compared with males for untreated periodontitis in Taiwan Chinese people.

Adult↗
PubMedDate not supplied

Image analysis in quantitative PCR. An application for the measurement of c-erbB-2 oncogene amplification in DNA from human tumours.

We present an application of image analysis for the direct quantification of PCR products after gel electrophoresis and ethidium bromide staining of DNA. This procedure has been applied to the development of an assay based on competitive PCR for the measurement of the degree of amplification of c-erbB-2 oncogene in DNA from human tumours. In this method two DNA species (genomic and competitor) compete for PCR amplification. Since results are calculated from the final competitor/genomic ratio any variable affecting the rate of PCR amplification has no effect on the accuracy of the ratio measurement. Results are reported which show that even large variations in the experimental conditions (number of PCR cycles, sample volumes and extracted DNA quality) did not interfere with the precision of the measurement of the competitor/genomic ratio.

Binding, Competitive↗
PubMed1984

Correlation between protein synthesis rate and nuclear morphology of human erythroblasts as determined by quantitative autoradiography and high-resolution image analysis.

Human erythropoiesis is an appropriate model for analyzing correlations between functional activity of cells during maturation and nuclear morphology as determined by high-resolution image analysis. In a previous study a relationship had been found between nuclear condensation and the proliferative activity of the cells. This present study analyzed the correlation between nuclear morphology and the protein synthesis rate. The latter was assayed by measuring the 14C-1-leucine incorporation rate utilizing the technique of quantitative 14C-autoradiography. The labeled cells were first classified according to conventional cytological criteria into four groups of increasing maturity. Following grain counting the nuclei were Feulgen-stained, and after removal of the silver grains, the local nuclear optical densities were evaluated by scanning. There was a nonlinear relationship between the protein synthesis rate and features representing the degree of chromatin condensation. This nonlinearity was explained by the mediator function of RNA, predominantly mRNA. The amount of protein produced at a given time depends on the transcriptional activity of the chromatin, the frequency of mitotic divisions partitioning the mRNA, and the half-life of the mRNA. It was concluded that the chromatin texture of erythroblasts reflects three different metabolic activities: the rate of DNA strand duplication, the transcriptional activity for structural proteins enabling a cell to grow and cycle, and for functional proteins, particularly hemoglobin. Since these three activities appear to be synchronized, it is understandable that functional as well as textural features can be used to perform a supervised classification by means of multivariate analysis. Application of the five most significant features allowed a consistent classification of the erythroblasts into the various cytological compartments in 76.7% of all cases, while the classification error of the observer amounted to 13.7%.

Autoradiography↗
PubMed1986

Periosteal resorption and periosteal neostosis: comparison of normal subjects and renal failure patients on chronic ambulatory peritoneal dialysis using MOP-3 image analysis system and a grading method.

This is the first known attempt to quantitate periosteal resorption (PR) and perisoteal neostosis (PN) by a semi-automatic image analysis system (Zeiss MOP-3). The normal ranges and errors for PR were found to be similar to those of a previous study using a measuring magnifier. The findings in chronic renal failure patients showed that MOP-3 measurements were actually diagnostically slightly less sensitive than the results by a simple grading method. Comparison with plasma-immunoreactive parathyroid hormone (iPTH) concentrations showed that while the latter had a higher sensitivity for detection of hyperparathyroidism, the radiologic parameters nevertheless showed abnormal PR in 12% of the observations where iPTH was normal. Both PR and PN correlated significantly with iPTH (r = 0.55 and 0.30 respectively, P less than 0.01).

Adult↗
PubMed2000

The consistency and reliability of periodontal bone level measurements using digital scanning radiographic image analysis--a pilot study.

The purpose of the present study was to evaluate the consistency and reliability of alveolar bone height measurement using digital scanning radiographic image analysis (DSRIA). A randomly selected (standardized paralleling technique) periapical radiographs of 20 molar teeth (10 maxillary molars and 10 mandibular molars) from 178 individuals with periodontitis were reporting or referred to the patient population of the dental clinics of the teaching hospital. Radiographic measurements were performed and read by two examiners, with a separation time of three weeks of different tooth groups and as established by double reading of 20 molar teeth in 10 individuals using the DSRIA. The calculating data of radiographic alveolar bone loss (RABL) measured and analyzed by the DSRIA for each molar group were compared based on the inter- and intra-examiners' data. The means and standard deviations were calculated to compare radiographs of the inter- and intra-examiners' groups. The reliability coefficients were computed to assess the consistency and reliability for each molar group. The results revealed that the intra- and inter-examiners' reliability coefficients ranged from 0.986 to 0.995 (p < 0.001, significantly different from 0). An excellent reproducibility was indicated in maxillary molar, mandibular molar and of both arches, respectively. It was concluded that the standard periapical radiograph using the DSRIA has the potential to be a valuable and reliable method in measuring linear alveolar bone defects caused by periodontitis.

Adult↗
PubMedDate not supplied

Image analysis methods for solitary pulmonary nodule characterization by computed tomography.

Computer software was designed for classifying solitary pulmonary nodules (SPNs) into benign and malignant from their CT images, using image analysis methods. The system made use of three features, computed from the CT density matrix of the SPN, and a class-discriminating algorithm. System evaluation was performed on 51 histologically confirmed SPNs of indeterminate CT diagnosis. Overall classification accuracy in distinguishing benign and malignant SPNs was 90.2%, while 83.3% of the benign and 93.9% of the malignant SPNs were correctly classified. The proposed system may be of value to the radiologist in assessing the probability of malignancy in patients with a solitary pulmonary nodule.

Adult↗
PubMed1996

Evaluation and prognostic value of DNA content and of morphometric parameters in malignant mesothelioma using digital image analysis.

Fifty-seven cases of malignant mesothelioma were analyzed for nuclear diameter, DNA content and ploidy-related parameters, using Feulgen stained paraffin sections with a digital imaging analysis system. Thirty cases had a mean nuclear diameter > 7 microns and 31 cases were classified as near-diploid. A statistically significant correlation between survival and the mean nuclear diameter (P = 0.0006) and between survival and DNA index (P = 0.007) was obtained. For other DNA content parameters (proliferation index, 5c exceeding rate), only one of the two statistical tests showed a significant correlation with survival while the other test was of borderline significance. In this malignant mesothelioma population, the prognosis for patients with the epithelial type was better than for those with sarcomatous tumours (P = 0.01). In this population of patients, about half of the malignant mesotheliomas were aneuploid. The mean nuclear diameter, DNA index analysis and proliferation index analysis of the tumour cells on Feulgen stained paraffin sections can be used as independent prognostic parameters.

Cell Nucleus↗
PubMed1987

Automated quantitative fluorescent image analysis of cervical cytology.

Cervical cytology from 122 patients with histories of one or more abnormal Pap smears were studied using slide-based automated quantitative fluorescence image analysis (QFIA) in order to determine the usefulness of the QFIA technique in detecting neoplasias. The purpose of the study was to evaluate the accuracy and validity of QFIA as a cytological method for the early detection of cervical cancer, based on comparisons with the conventional Pap smear and histopathology. The results of the analysis demonstrated that the sensitivity of the automated QFIA cytology was 100% for high-grade neoplasms (CIN III and invasive carcinoma), compared with 82% for the Pap smear. Evaluation of lower grade neoplasms was also performed. Initial analyses of the data indicate that QFIA, which uses objective biochemical criteria to identify cells with increased nuclear nucleic acid content, is a more sensitive detector of cervical neoplasia of all grades than is conventional Pap cytology.

Acridine Orange↗
PubMed1990

Allo-activated CD4+ and CD8+ lymphocyte subsets: new ultrastructural findings based on computer-assisted image analysis.

Primary allo-stimulation induces substantial and differentiated modifications in the development of cytoplasmic organelles of peripheral T-lymphocyte subsets. The present computer-assisted image analysis provides evidence that the CD4+ subset undergoes significant increase in organelle density after stimulation, while the CD8+ subset exhibits a post-stimulation organelle development proportional to the cell size. Each immunological subset contains two distinct patterns of cytoplasmic organization, here defined as type I (containing a few cytoplasmic organelles) and type II (with well-developed synthesis and storage organelles). On the basis of these findings cytologic parameters could be ascribed to a heterogeneous proliferation of functionally distinct T-cell clones in CD4+ and CD8+ subsets.

CD4-Positive T-Lymphocytes↗
PubMed2000

Simple horizontal averaging programme enables shade correction for image analysis in psoriasis.

Computer-assisted area measurement of skin lesions would be useful for the assessment of disease severity. Difficulties can be encountered, however, when lesions cannot simply be separated using the normal threshold tool of an image analyser. Owing to body curvature, peripheral sites are usually shadowed. To obtain a well-fitting curved line to account for body curvature-induced glare and shadow, we devised a simple C-programme for averaging neighbouring pixels on the same horizontal line. An image was captured from a colour slide to the image analysis system. C++ was used for programming. Execution of the averaging programme with the original image resulted in a background brightness image file. When this was subtracted from the original image, the lesions were easily detected using the standard threshold tool and the percentage of area involved was calculated. This method is sufficiently accurate for the assessment of disease severity.

Humans↗
PubMed1991

Quantification of tartrate resistant acid phosphatase activity using a computerized image analysis system.

Tartrate resistant acid phosphatase (TRAP) has been accepted as a marker for identification of osteoclasts. A method is reported here for quantitating TRAP using an image analysis system. The amount of the enzyme specific to osteoclasts can be used to differentiate osteoclasts from other cells capable of TRAP expression. TRAP expression characteristic of the osteoclast was compared with that of multi-nucleated giant cells (MNGC)s recruited to the site of subcutaneously implanted mineralized bone matrix. Two weeks post-implantation, the pellets were removed and processed for the demonstration of TRAP along with rat proximal tibiae. A large amount of TRAP was consistently expressed by the in situ osteoclasts. The MNGCs associated with the mineralized bone implants expressed little if any TRAP reaction product. Using this system, the amount of TRAP reaction product or any other enzyme reaction product expressed can be objectively and reproducibly quantitated.

Acid Phosphatase↗
PubMed1994

Echographic evaluation with image analysis of irritant reactions induced by nonanoic acid and hydrochloric acid.

Skin reactions to 40% nonanoic acid in propanol (NON) and to 4% hydrochloric acid were evaluated by image analysis of 20 MHz B scan recordings (Dermascan C, Cortex Technology). 18 women, aged 18 to 45, were patch tested with 24-h application time, and clinical and instrumental evaluations were performed at the beginning of the experiment, and 24 and 48 h after patch testing. To check possible regional variations in reactivity to NON and HCl, both substances were applied 2 x on the same forearm. As control tests, saline solution, propanol and sodium lauryl sulfate (SLS) 3% were applied. Echographic images were processed by a program enabling numerical representation of picture data, based on attribution of fictional values to the echoes' amplitudes, selection of amplitude bands of interest, binary transformation of the image, and calculation of the extension of areas reflecting within the same amplitude range. Sonographic recordings were evaluated by an amplitude interval marking hyporeflecting parts of the dermis (corresponding to edema and inflammatory infiltration), and by a band highlighting the entrance echo (epidermis). Our evaluations showed that extension of the hypoechogenic area of the dermis increases according to intensity of inflammatory reaction for all irritant substances. A clear decrease in reflectivity of the epidermis echo at 24 h was visible at SLS patch test test sites, whereas at patch test sites performed with NON and HCl, there was a trend towards an increase in values of hyperreflecting pixels. No significant variations between data recorded at proximal compared to distal skin sites were observed for NON and HCl. In conclusion, the echographic technique provides a method for quantification of the dermal inflammatory reaction, and also for description of skin reactions induced by irritant substances, according to their specific epidermal effects.

Adolescent↗
PubMedDate not supplied

New software for lens retro-illumination digital image analysis.

PURPOSE: To describe functions of new software for cataract assessment and compare its validity with that of the Nidek EAS-1000 software (Nidek, Japan). METHODS: A new Microsoft Windows 3.1/95 (Microsoft, USA) compliant software, Retroillumination Image Analysis (RIA), has been developed. The cataract reading is based on the contrasts in illumination between the opaque and transparent areas of the lens. Image loading, pupil detection and image analyses are automated. Differentiation between the different cataract types (cortical/posterior subscapsular) and other opacities is possible. RESULTS: The program was tested on 233 Nidek EAS-1000 images. In all, 148 eyes had clear media or cortical cuneiform cataract, 37 also had confounding opacities and 48 had no confounding opacities but pupils were unevenly illuminated. The results of analysis with both Nidek EAS-1000 and RIA software were compared against clinical Wilmer grading. The correlation of cortical opacity size in Nidek EAS-1000 3.01c and RIA software, respectively, were 0.50* and 0.57* for whole data set, 0.54* and 0.55* for subgroup with no confounders or artefacts, 0.54* and 0.66* for subgroup with artefacts, 0.27 (P < 0.105) and 0.65* for subgroup with confounders (*P < 0.001). CONCLUSION: The RIA software significantly improves the accuracy of cataract measurement in lens images with uneven pupil illumination or confounding opacities. Automation of (i) image loading, (ii) pupil detection and (iii) defining of the opacity area increases the efficiency of digital eye photography, eliminates human errors and speeds assessment.

Cataract↗
PubMed1987

Quantitation of cellular resolution in situ hybridization histochemistry in brain by image analysis.

A new method for relative quantitation of mRNA levels with single neuron resolution is described. Hybridized tissue sections are emulsion dipped, exposed, and developed. The resulting silver grains are visualized using dark-field microscopy at high magnification. The method relies on computer-based image analysis of sequentially located, high resolution, small fields containing the cell images, each of which is analyzed for mRNA content. Maps of cell distributions are constructed, with cell marks color-coded for relative mRNA levels, yielding previously unavailable information on regional distribution of quantitative cellular expression of specific mRNA in brain.

Brain Chemistry↗
PubMed1991

Cell migration and actin organization in cultured human primary, recurrent cutaneous and metastatic melanoma. Time-lapse and image analysis.

Random cell migration and actin organization in seven human primary, recurrent cutaneous, and metastatic melanoma cell lines were studied by time-lapse video recording and image analysis. The migration of over 800 randomly selected cells from the cell lines were recorded using an inverted microscope with an attached incubator housing. The fraction of cells with random migration rates greater than 10 microns/hour was 8% in an established primary melanoma cell line, 2% and 34% in two recurrent cutaneous melanoma cell lines, and 5%, 30%, 31%, and 60% in four metastatic cell lines. The three metastatic cell lines with significantly higher mean migration rates (P less than 0.001) were derived from lymph node metastases, whereas the fourth metastatic cell line was derived from a visceral metastasis. The cellular morphology and presence of cell nests in the original tissue correlated with in vitro cell morphology and the formation of colonies. The ability of cells to organize actin into stress fibers directly correlated with significantly higher random migration rates and lack of colony formation. Characterization of random migration rates and actin organization of human melanoma cells that are isolated from different stages of tumor progression may lend insight into metastasis.

Actins↗
PubMedDate not supplied

Measurement of blood flow velocity in feeder vessels of choroidal neovascularization by a scanning laser ophthalmoscope and image analysis system.

PURPOSE: To measure the blood flow velocities in feeder vessels of patients with choroidal neovascularization (CNV) secondary to age-related macular degeneration. METHODS: We examined the early images of indocyanine green videoangiography (v-ICGA) in 29 patients (29 eyes) with CNV, in whom feeder vessels could be identified by v-ICGA. The v-ICGA images were installed in a personal computer. With original software, optical density measurements were performed for the determination of dye-dilution curves. The flow velocity in a CNV feeder vessel was obtained by analyzing the dye-dilution curves. RESULTS: The mean flow velocity in feeder vessels was 33.8 +/- 32.5 mm/s. The flow velocity in feeder vessels of CNV with a diameter of 1.5 mm or larger was significantly higher than that in feeder vessels of CNV with a diameter smaller than 1.5 mm (P <.05, unpaired t-test). CONCLUSIONS: The flow velocity in CNV feeder vessels can be measured with v-ICGA and a computer-based image analysis system. This system would be useful in the evaluation of choroidal circulation.

Aged↗