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PubMed2002

Role of color flow Doppler sonography in pre-operative diagnostics of the thyroid pathology.

BACKGROUND: The aim of this work is to demonstrate the high effectiveness of preoperative diagnosis by echotomographic study of thyroid nodules through color-Doppler sonography integrated by B-mode. The authors performed both B-mode ultrasonography and color-Doppler sonography on 125 patients expecting total thyroidectomy surgical intervention, without a previous evaluation of a number of other already performed clinical and instrumental tests. After the intervention, we compared the histologic test with the data drawn from the ultrasound scan, in order to demonstrate that color-Doppler sonography is able to provide for additional diagnostic information in the preoperative period. METHODS: One hundred and twenty five patients with thyroid pathologies were examined by both B-mode and color-Doppler sonography. Two diagnoses were made for each clinical case: the first supported by B-mode data, the second based on vascularity. Our aim was to check color-Doppler's ability to provide new information in the ultrasound diagnosis. All patients underwent a total thyroidectomy surgical intervention. The data were examined by K concordance test. RESULTS: Ultrasound data were compared with the histologic test, which showed 118 (97.4%) benign and 7 (5.6%) malignant lesions. B-mode ultrasound test gave a correct diagnosis in 115 (97%) out of 118 benign lesions and in 4 (57%) out of 7 malignant lesions, while 3 (2.5%) out of 118 cases were false positive and 3 (42.8%) out of 7 were false negative. In those cases showing a wrong conventional ultrasound diagnosis, after the integration of B-mode with color-Doppler results, a decrease was recorded in both false negative and false positive. CONCLUSIONS: Even if no correspondence was found between the different aspects of blood flow and the histologic types of lesions, this experience proves that the color-Doppler test has a high predictive value of benignity in cases with pattern I II and IV, while lesions with pattern III should be more carefully examined, since both malignant and benign lesions belong to this group. From the data drawn from this study, we are able to infer that color-Doppler sonography is undoubtedly an advantage not only in terms of cutting the false negatives, but also in the aim of obtaining a higher effectiveness in the screening of goitrogenic pathology.

Adenocarcinoma, Follicular↗

PubMed2001

[Experimental study on ergonomical color matching design of virtual crew cabin layout in manned spacecraft].

Objective. To approach general principles of color matching for crew module layout and to provide its ergonomical evaluation with basic data. Method. First, according to some ergonomic rules a virtual reality experimental system was set up, then 64 subjects of different ages and with some background of spaceflight were offered a color matching example according to their own choice in advance. Finally, all the hues, saturations, and lightnesses of the selected colors and their total number were statistically analyzed by SPSS 8.0 software. Result. After choosing the colors for items (standard cabinets, floor, handrails, supports and etc.) in the crew cabin, the mean kinds of color hue matching in the cockpit was 5. In addition, above half of subjects endorsed the example colors but its saturation and lightness were a little higher than those of the example every time. Although its distribution was discrete, there still was a common agreement on color matching (about 50%). Conclusion. When the color matching of crew module in long time flight was ergonomically designed, generally, cool and warm hues should be taken into consideration, and their total number need be controlled to be under 5 so as to satisfy human psychological characters.

Color Perception↗

PubMed2002

The contributions of color to recognition memory for natural scenes.

The authors used a recognition memory paradigm to assess the influence of color information on visual memory for images of natural scenes. Subjects performed 5%-10% better for colored than for black-and-white images independent of exposure duration. Experiment 2 indicated little influence of contrast once the images were suprathreshold, and Experiment 3 revealed that performance worsened when images were presented in color and tested in black and white, or vice versa, leading to the conclusion that the surface property color is part of the memory representation. Experiments 4 and 5 exclude the possibility that the superior recognition memory for colored images results solely from attentional factors or saliency. Finally, the recognition memory advantage disappears for falsely colored images of natural scenes: The improvement in recognition memory depends on the color congruence of presented images with learned knowledge about the color gamut found within natural scenes. The results can be accounted for within a multiple memory systems framework.

Adult↗

PubMed2003

Color removal ability of a streptomycin resistant decolorizing strain Rhodococcus erythropolis (ATCC:4277.1).

Rhodococcua erythropolis (ATCC 4277.1) is a streptomycin resistant mutant of ATCC 4277, which can decolorize the sulfonated azo dye of Orange II and Amido Black. Pseudomonaes luteola is a decolorizing strain, which was isolated from sludge resulting from the treatment of dyeing wastewater. This study had two purposes: 1) to determine the color removal capacity of R. erythropolis (ATCC 4277.1) for Red 22, V2RP and RP2B dyes; and 2) to compare the decolorization capability of R. erythropolis (ATCC 4277.1) to that of P. luteola, a wild type decolorizing strain. R. erythropolis (ATCC 4277.1) grew well in broth containing the azo dyes of Red 22, V2RP or RP2B, and the color of azo dyes could be removed within five days of incubation. The total percentage of color removal was 70%, 30% and 23%, respectively. Color removal by R. erythropolis occurred through a process of degradation, since after five day's incubation in a dye containing broth, the color of R. erythropolis cells remained the same as their original pinkish white color. Comparison of the color removing ability between R. erythropolis and P. luteola showed that the specific color removal (SCR) of R. erythropolis was 1.52 mg of RP2B degraded per gram of dried cells, and that of SCR of P. luteola was 31.7 mg, which was 30 fold higher than that of R. erythropolis.

Azo Compounds↗

PubMed1999

Feasibility study of an ultrasound contrast agent (levovist) in color Doppler imaging of liver neoplasms.

The purpose of this study was to determine the efficacy of using an ultrasound contrast agent (levovist) to enhance the color Doppler imaging of liver neoplasms. Thirty patients with hepatic tumors were enrolled in this study. After intravenous administration of levovist, the color Doppler signals of normal hepatic vessels were enhanced. In various hepatic tumors, the different patterns of tumor vascularity were observed, which had not been demonstrated in conventional non-contrast color Doppler imaging. In 11 of 16 patients with hepatocarcinoma, additional color Doppler signals were observed in the central part of the tumors. On the contrary, 3 patients with metastatic liver lesions the enhanced color Doppler signals appear only at the peripheral of tumors. A typical rim-like color enhancement was seen in 2 of the 3 cases. In six patients with hepatic hemangiomas contrast-enhanced color Doppler imaging demonstrated the blood vessels at the margin of the neoplasms. Contrast-enhanced color Doppler imaging improves the visualization of the hepatic neoplasm vascularity. This technique holds great promise for detecting small liver tumors and differentiating hepatic neoplasms.

Adult↗

PubMed1992

Cortical area V4 and its role in the perception of color.

The color and lightness vision of three monkeys with bilateral removal of cortical area V4 and three unoperated controls were tested by measuring their ability to discriminate between two rows of colored or gray stimuli. In one row, the stimuli were ordered in terms of either chromaticity or luminance, whereas in the other row they were disordered. Their ability to select the odd-one-out in an array of colors or grays and to select the colored patch from an array of achromatic grays was also assessed. Unlike an achromatopsic patient tested previously in an identical fashion, monkeys with V4 lesions performed indistinguishably from controls in the oddity test. The animals lacking V4 were slightly impaired at discriminating between ordered and disordered arrays of colors or grays, but the color impairment was no more severe than the impairment with grays. These deficits were readily accounted for in terms of the conspicuous deficits in pattern discrimination apparent in a nine-choice pattern oddity task. The results do not support the view that cortical area V4 in the monkey is the homolog of the cortical "color center" in humans, located in the lingual and fusiform gyri and damage to which leads to the clinical syndrome of cerebral achromatopsia, unless it is the additional damage to underlying white matter that leads to the severe color disorder in patients.

Animals↗

PubMed2004

[A preliminary study on the color effect of IPS Empress all-ceramic veneers].

OBJECTIVE: To evaluate the opaquing capacity, color compatibility and stability of IPS Empress all-ceramic veneers. METHODS: A total of 86 IPS Empress all-ceramic veneers were made for 18 patients. The patients were divided into three groups: Group A was tetracycline teeth, 64 veneers for 5 patients; Group B was non-tetracycline teeth, 22 veneers for 13 patients; Group C was 22 natural vital teeth with normal color as control group. Before and after veneers were inserted, ShadeEye NCC was employed to obtain L * a * b * values of each tooth. The values of cemented veneers used as the baseline, the L * a * b * values of each veneer were measured half a year, 1 year, and 2 years after restoration respectively. All L * a * b * values at different evaluation times were analyzed by SPSS 10.0. RESULTS: Before and after veneers were restored, the L * a * b * values of both Group A and Group B were significantly different, the color difference being 5.01 and 4.15 respectively. The color difference between Group A and selected shade guides was 2.45. Compared with the baseline value, the L * value of Group A significantly decreased 2 years after restoration, but the DeltaE of different evaluation times was not significantly different. The color difference between Group B and Group C was 0.22 and there was no significant color difference after restoration. CONCLUSIONS: IPS Empress all-ceramic veneers have excellent opaquing capacity, color compatibility and stability to non-tetracycline teeth. To tetracycline teeth IPS Empress all-ceramic veneers have a certain opaquing capacity, but they cannot completely match with shade guides; the L * value is significantly different after restoration and further studies are needed to evaluate its color effect.

Adolescent↗

PubMed2005

[Inheritance of coat color in the mole vole (Ellobius talpinus Pallas)].

Based on the ecological features of the mole vole, family analysis of the inheritance of coat color was performed with the use of material collected in a wild population. Analysis of coat color in parents and offspring has demonstrated that the offspring segregation into black and nonblack animals after crosses of different types agrees with the hypothesis on the monogenic inheritance of these color variations. Black mole voles are homozygous for the recessive allele (genotype aa). Homozygotes for the dominant allele (AA) are brown. Heterozygotes (Aa) may be brown or have transitional color. The mean frequency of brown coat color in heterozygotes is 0.509 and is very variable. The higher the color intensity in black elements of parent coat color, the more is the offspring coat color saturated with these elements.

Animals↗

PubMed1992

Different patterns of X inactivation in MZ twins discordant for red-green color-vision deficiency.

Two female identical twins who were clinically normal were obligatory heterozygotes for X-linked deuteranomaly associated with a green-red fusion gene derived from their deuteranomalous father. On anomaloscopy, one of the twins was phenotypically deuteranomalous while the other had normal color vision. The color vision-defective twin had two sons with normal color vision and one deuteranomalous son. X-inactivation analysis was done with the highly informative probe M27 beta. This probe detects a locus (DXS255) which contains a VNTR and which is somewhat differentially methylated on the active and inactive X chromosomes. In skin cells of the color vision-defective twin, almost all paternal X chromosomes with the abnormal color-vision genes were active, thereby explaining her color-vision defect. In contrast, a different pattern was observed in skin cells from the woman with normal color vision; her maternal X chromosome was mostly active. However, in blood lymphocytes, both twins showed identical patterns with mixtures of inactivated maternal and paternal X chromosomes. Deuteranomaly in one of the twins is explained by extremely skewed X inactivation, as shown in skin cells. Failure to find this skewed pattern in blood cells is explained by the sharing of fetal circulation and exchange of hematopoietic precursor cells between twins. These data give evidence for X inactivation of the color-vision locus and add another MZ twin pair with markedly different X-inactivation patterns for X-linked traits.

Chromosome Mapping↗

PubMed1990

[Color changes of light-cured composite resins. (1)].

The purpose of this study was to investigate the color changes of light-cured composite resins over specified periods of time. Composite resin disks which were 10 mm in diameter and 1 mm in thickness, and made by the 3M Co. light-cured composite resin Silux Plus (shades: U, Y, DY, L, G, UO, YO) were made with 2 minutes of light exposure through a 1 mm thick glass plate. The specimens were stored in 37 degrees C artical saliva. Chromatical values of the specimens immediately after curing, 1 day, 1 month, 3 months, 6 months and 1 year after curing were measured without background color, backed by a white plate. Color measuring was performed with the Murakami Color Research Laboratory Fast Spectrophotometer CMS-500 and the Flexible Sensor FS-3. 1) In the cases without background color, the delta E*ab values of all shades increased for 1 year proportionately to the time elapsed. In the cases backed by a white plate, the delta E*ab values of all shades increased for 6 months after curing, however, compared to the 6 month delta E*ab values, the 1 year delta E*ab values increased in some shades and decreased in other shades. 2) Both in the cases of with and without background color, compared to the delta E*ab values of immediately after curing, the 3 month delta E*ab values of all shades were over 1.2, and the 1 year delta E*ab values of many shades were near or over 2.5 and detectable to the naked eye. 3) Both in the cases of with and without background color, the L* values of all shades decreased for 6 months after curing. However, compared to the 6 month L* values, the 1 year L* values decreased in some shades and increased in other shades. 4) In the cases without background color, the a* values of all shades increased for 1 year after curing. In the cases backed by a white plate, the a* values of all shades increased for 6 months, however, compared to the 6 month a* values, the 1 year a* values of all shades decreased.(ABSTRACT TRUNCATED AT 400 WORDS)

Bisphenol A-Glycidyl Methacrylate↗

PubMed1988

Differences in color preferences of school-age children in varying stages of health: a preliminary study.

The purpose of the study was to determine the preferences in color of children ages 7-12 who were physically well and those in varying states of ill health. Data were collected on a convenience sample of 72 subjects. Children were asked to name their favorite color, and then select the color they preferred from a set of color squares and the picture they preferred from two sets of colored pictures. General information about the child's diagnosis, number of days hospitalized, and number of siblings was also obtained along with other projective information. Data were analyzed using chi-square to test the hypotheses. Logistic regression models were used to examine the independent variables sex, age group, and health state in a multivariate manner by fitting the models with the choices of red, blue, or green as the first or second color on the Luscher Color Test as the dependent variable. This analysis was repeated with the Picture Test as the dependent variable. The only regressor for these models that was significant was health state. Significant differences were found (p less than 0.05 level) in color preferences of physically well children and those who were ill; in acutely ill and chronically ill children; in physically disabled and acutely ill children; and in children ages 7-9 and 10-12.

Child↗

PubMed1978

[Lens caused shifts in color co-ordinates measured on the ocular fundus (author's transl)].

Changes in certain areas of the ocular fundus are frequently accompanied by changes in the spectral distribution of the reflected light. In many diseases of the ocular fundus, it is desirable to have an objective difinition of the color of the fundus during a particular phase of the disease. An instrument designed by Carl Zeiss, Oberkochen, West Germany, provides a satisfactory solution to the problem of measuring color on the ocular fundus. Transformational equations make it possible to convert the measurement parameters obtained by visual comparison into standardized color measurment values. The measurement error is slighter than necessary for clinical examinations. The possible influence of the ocular lens's own color on the color co-ordinates measured on the fundus was examined. Measurement of fundus color in three suitable situations showed no differences in color coordinates on the fundus between aphakic eyes of younger patients and eyes containing lenses. Incipient cataracts cause only a slight shift of the color co-ordinates. More marked cataracts cannot lead to erroneous interpretation of the measurement results, since measurement with this method is no longer technically possible in such cases.

Adolescent↗

PubMed1993

[Computerized image analysis in the glaucomatous optic disc color changes].

The disc rim color changes in 40 eyes with primary open angle glaucoma (POAG) were studied using a computerized color analysis system. Optic disc color was evaluated by quantification of the red ratio based on the analyzed level of red, green, and blue elements. The correlation among the changes in neuroretinal rim color, visual field and cup area to disc area ratio (C/D.A) was evaluated. In 18 eyes in the early stage, with total initial loss less than 100 dB, the disc color change correlated with both mean sensitivity decrease (Pearson's r = 0.7410, p = 0.0004) and C/D. A increase (Pearson's r = 0.4698, p = 0.0492). In 22 eyes in the middle stage with total initial loss over 100 dB, the disc color variation correlated with mean sensitivity loss (Pearson's r = 0.7503, p < 0.0001) but not with C/D. A (Pearson's r = 0.2980, p = 0.1780). Neuroretinal rim color changes correlated with the value of mean sensitivity loss at any stage of POAG. These results suggest that neuroretinal rim color change in eyes at an early stage depend on a different histological change from that in the middle stage in POAG.

Color↗

PubMed1993

Impact of a color-flow duplex surveillance program on infrainguinal vein graft patency: a five-year experience.

PURPOSE AND METHODS: The contribution of color-flow duplex surveillance to improving vein graft patency was evaluated in two patient groups after 201 infrainguinal bypass procedures were performed during a 5-year period. Incidence of revision procedures and the primary and assisted primary patency rates were compared for 160 bypass grafts monitored during the first 2 years by use of color-flow duplex scanning of the vein graft and adjacent arterial segments (color-flow surveillance group) versus 41 bypass grafts monitored by use of clinical assessment alone (clinical follow-up group). Only grafts that were patent after the first postoperative month are considered. RESULTS: The two groups were comparable with regard to most of the pertinent clinical factors. Stenotic lesions were identified in 58 bypass grafts, and severity was determined by use of intraarterial digital subtraction angiography. Eighteen bypass grafts with stenoses did not undergo a revision for reasons that were determined by the doctor, the hospital, or the patient. The occlusion rates of revised and nonrevised stenotic grafts were compared for lesions of different severity. None of the grafts for stenoses with 30% to 49% diameter reduction (DR) failed during follow-up. Occlusion occurred in 57% of the nonrevised and 9% of revised grafts (p = 0.047) for stenoses with 50% to 69% DR. Stenoses with 70% or greater DR were associated with graft failure in 100% of nonrevised bypasses and in 10% of revised grafts (p = 0.004). The assisted primary patency rate was higher in grafts that underwent color-flow surveillance compared with grafts with that underwent clinical follow-up (3-year patency rates of 91% and 72%, respectively; p = 0.004). The independent correlation of color-flow surveillance with higher patency rates was demonstrated in a proportional hazard analysis. The relative risk (probability of occlusion) in color-flow surveillance grafts is less than one third of the relative risk in bypass grafts that underwent clinical follow-up. CONCLUSIONS: We conclude that revision procedures were more optimally used during color-flow surveillance, whereas asymptomatic stenotic graft lesions are missed with clinical follow-up, which results in a higher percentage of graft failures. Overall graft patency rates can be improved with use of color-flow duplex surveillance and repair of significant stenotic lesions.

Angiography, Digital Subtraction↗

PubMed1998

Evaluation of regional left ventricular wall motion with color kinesis: comparison with two-dimensional echocardiography in patients after acute myocardial infarction.

BACKGROUND: Color kinesis (CK) is a new echocardiographic technique for the assessment of left ventricular (LV) wall motion based on acoustic quantification. Using integrated backscatter data, this technique identifies the pixel value transitions from blood to myocardial tissue throughout systole and tracks endocardial motion in real time. The color-encoded images, built on a frame-by-frame basis by adding one color at a time, provide an integrated display of the timing and amplitude of endocardial motion in a single end-systolic frame. Recent studies have shown that CK is a promising clinical tool for quantitative assessment of regional LV function. OBJECTIVES: The aim of this study was to evaluate the feasibility and accuracy of CK in identifying the regional wall-motion abnormalities diagnosed by conventional two-dimensional (2-D) echocardiography in patients after acute myocardial infarction (AMI). METHODS: The end-systolic color overlays were analyzed using a method to quantify the regional timing and amplitude of endocardial systolic excursion (ESE) based on the count of the numbers of colors. At this point, the total duration (ESE timing) and distance (ESE amplitude) of endocardial excursion from end-diastolic to end-systolic color-frame was calculated in each segment. In 54 patients after AMI, we compared the feasibility and ability of CK superimposed on 2-D superimposed on 2-D superimposed on 2-D echocardiographic images and visual 2-D echo analysis to evaluate the endocardial border excursion in parasternal short-axis (SAX) and apical four-(AP4CH) and two-(AP2CH) chamber views. In 20 normal subjects, the end-systolic color overlays were used to evaluate the variability of the measurements of ESE timing (msec) and amplitude (cm) and to define the reference values. Image quality was considered adequate if at least 12 of 16 segments could be evaluated for systolic function by conventional visual 2-D echo. Among 54 patients, 35 with adequate studies were selected to determine the accuracy of quantitative analysis of CK images in identifying regional wall-motion abnormalities. RESULTS: The SAX view was obtained in 36 of 54 patients; of the possible 216 segments, 210 (97%) were adequately visualized by 2-D echocardiography and 207 (96%) by CK. Apical views were obtained in 50 patients (93%); of the possible 300 segments, 93% were visualized by 2-D echocardiography and 90% by CK in the AP4CH view and 94% and 92%, respectively, were visualized by the two methods in the AP2CH view. In normal subjects, measurements of ESE timing and amplitude were found to be consistent and the mean values were 346 msec (range 280-360) and 0.99 cm (range 0.72-1.26) respectively. In the 35 selected patients, 2-D echocardiography identified 355 normokinetic segments in which ESE timing and amplitude were similar to the reference values. In 83 hypokinetic segments and 108 akinetic segments, ESE timing and amplitude were significantly inferior to values of normokinetic segments (p < 0.001). An ESE timing below the reference values of 280 msec identified all of the 191 asynergic segments (sensitivity and specificity = 100%) and an ESE amplitude of less than 0.70 cm identified 188 asynergic segments (sensitivity = 98% and specificity = 99%). CONCLUSIONS: CK showed good feasibility and diagnostic accuracy in identifying regional wall motion abnormalities in patients with acute myocardial infarction. The model used in our study for the quantitative analysis of color kinesis images, which provided easy and feasible indices of timing and amplitude of endocardial excursion, enabled fast and objective evaluation of LV regional wall motion.

Acute Disease↗

PubMed1999

Performance of red-green color deficient subjects on the Farnsworth Lantern (FALANT).

BACKGROUND: The Farnsworth Lantern (Falant) is an occupational color vision test intended to identify people with significant red-green color deficiency who are unable to name aviation, marine or railway signal lights correctly. The colors shown are white, green and red selected to be within protan and deutan isochromatic zones. HYPOTHESIS: The Falant grades the severity of color deficiency and identifies subjects with different types of deficiency. METHOD: 270 color deficiency subjects (diagnosed with the Neitz anomaloscope) were examined. A subset of 108 subjects also completed the Farnsworth D15 and the Farnsworth-Munsell 100 hue test. RESULTS: All dichromats and 75% of anomalous trichromats failed the Falant. The mean error score of dichromats was greater than that anomalous trichromats, but errors were made in a similar number of qualitative color naming categories. The range of Falant error scores was continuous with no demarkation between the criteria for pass and fail. It was not possible to identify anomalous trichromats likely to pass the Falant from the size of the anomaloscope matching range or from the results of Farnsworth-Munsell tests. CONCLUSIONS: People with severe red-green color deficiency fail the Falant, but neither the type nor the severity of color deficiency can be determined either from the qualitative results or from the error score.

Aviation↗

PubMedDate not supplied

Visual sensitivity to color errors in images of natural scenes.

Simple color-difference formulae and pictorial images have traditionally been used to estimate the visual impact of color errors introduced by image-reproduction processes. But the limited gamut of RGB cameras constrains such analyses, particularly of natural scenes. The purpose of this work was to estimate visual sensitivity to color errors introduced deliberately into pictures synthesized from hyperspectral images of natural scenes without gamut constraints and to compare discrimination thresholds expressed in CIELAB and S-CIELAB color spaces. From each original image, a set of approximate images with variable color errors were generated and displayed on a calibrated RGB color monitor. The threshold for perceptibility of the errors was determined in a paired-comparison experiment. In agreement with previous studies, it was found that discrimination between original and approximate images needed on average a CIELAB color difference DeltaEab* of about 2.2. Although a large variation of performance across the nine images tested was found when errors were expressed in CIELAB units, little variation was obtained when they were expressed in S-CIELAB units.

Color↗

PubMed2004

Color vision testing.

The science of color vision testing has evolved since its inception in the late 1700s. Since then, the rudimentary technique of comparing color names has been replaced by more sophisticated methods. Commonly used tests in clinical practice today include isochromatic plates, arrangement tests, anomaloscopes, and lantern tests. Each category has unique attributes that make it suitable for a particular clinical situation. The clinician should be aware of the requirements for administering and grading each test type. Factors such as the quality of the illuminant and the size of the field of view are important elements in setting up a proper color vision laboratory. Currently, no treatment exists for congenital color vision defects. However, studies show that diagnosis of these defects early in life may help children adjust better to tasks at school and may help adults understand their limitations at work. Acquired color vision defects are often used as markers of ocular pathology in the clinical setting. Different color vision tests are appropriate for diagnosing the different categories of defects. Sometimes, a battery of tests may be appropriate. This paper is a review of the current knowledge in the field of color vision testing.

Color Perception↗