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PubMed1989

Sources of variability for Doppler color flow mapping of regurgitant jets in an animal model of mitral regurgitation.

To determine whether Doppler color flow mapping could be used to quantify changing levels of regurgitant flow and define the technical variables that influence the size of color flow images of regurgitant jets, nine stable hemodynamic states of mitral insufficiency were studied in four open chest sheep with regurgitant orifices of known size. The magnitude of mitral regurgitation was altered by phenylephrine infusion. Several technical variables, including the type of color flow instrument (Irex Aloka 880 versus Toshiba SSH65A), transducer frequency, pulse repetition frequency and gain level, were studied. Significant increases in the color flow area, but not in color jet width measurements, were seen after phenylephrine infusion for each regurgitant orifice. For matched levels of mitral regurgitation, an increase in gain resulted in a 125% increase in color flow area. An increase in the pulse repetition and transducer frequencies resulted in a 36% reduction and a 28% increase in color flow area, respectively. Jet area for matched regurgitant volumes was larger on the Toshiba compared with the Aloka instrument (5.2 +/- 3.1 versus 3.2 +/- 1.2 cm2, p less than 0.05). Color flow imaging of mitral regurgitant jets is dependent on various technical factors and the magnitude of regurgitation. Once these are standardized for a given patient, the measurement of color flow jet area may provide a means of making serial estimates of the severity of mitral insufficiency.

Animals↗

PubMed1993

Effects of adjacent surfaces of different shapes on regurgitant jet sizes: an in vitro study using color Doppler imaging and laser-illuminated dye visualization.

OBJECTIVES: The present study was designed to estimate the influence of different-shaped adjacent surfaces on regurgitant jets as assessed by color Doppler imaging and laser-illuminated dye optical visualization. BACKGROUND: Because color Doppler techniques provide real-time two-dimensional imaging of flow, the evaluation of valvular regurgitation by analysis of variance-encoded regurgitant jets by this method has been widely used in clinical studies. However, recent studies have demonstrated that color Doppler jet sizes are affected not only by several hemodynamic factors and instrument settings but also by the interaction between jets and adjacent wall surfaces. In clinical conditions, jets may interact with adjacent walls of variable shapes that might have different effects on the jet size. METHODS: An in vitro model was constructed consisting of a rigid, optically clear receiving chamber that had no outlet resistance and had a pulsatile pump ejecting through 1.5, 2.3 and 3.1 mm2 inflow orifices into the chamber. The surfaces were flat or smoothly and equally curved, convex and concave aluminum positioned at 0, 2 and 4 mm from and to the side of the inflow orifices. The pump was run with stroke volumes from 0.5 to 3.0 ml and with a pulse frequency of 70 beats/min. The echocardiographic and laser beams were aimed at the inflow orifice imaging jets perpendicular to the surfaces (vertical view) through the central plane of the jet flows. Maximal jet areas were measured by both color Doppler techniques and laser-illuminated dye visualization. RESULTS: Color Doppler study showed fair correlation between the jet areas and the stroke volumes (r = 0.83 to 0.99), but the jet sizes under different surface conditions were variable. All the surface jet areas at a jet-surface distance of 0 and 2 mm were smaller than free jet areas at the same stroke volume for both flat and convex surfaces (p < 0.001). Flow constraint by the concave surface resulted in the smallest jet areas (p < 0.001). The color Doppler jet areas on the curved surfaces were significantly smaller than the laser-illuminated dye visualization jet areas (p < 0.01 to 0.0001). However, at intermediate jet-surface distances (4 mm and sometimes 2 mm with higher velocity flows), jet interaction with the flat and especially with the convex surface resulted in larger jets. This effect was most pronounced on dye fluorescence studies because flow around these jets consisted mainly of low velocity vortical events with only partial surface adherence and these low velocity swirling flows were not well imaged by color Doppler technique. CONCLUSIONS: Our study suggests that the different-shaped adjacent surfaces with different degrees of flow alterations resulted in variable decreases in jet size and that color Doppler imaging could not encode and image the angled and low velocity swirling events well when jets flowed along the curved surfaces. These effects need to be taken into account when interpreting color Doppler images.

Analysis of Variance↗

PubMed2006

Interactions of environmental factors influencing pupal coloration in swallowtail butterfly Papilio xuthus.

The swallowtail butterfly Papilio xuthus Linné [Lepidoptera: Papilionidae] exhibits pupal protective color polyphenism. Interactions of various environmental factors on pupal coloration were analyzed in non-diapausing individuals. Under sufficient light (200lux), most pupating larvae became green pupae when the surface of the pupation site was smooth, while they became brown when the surface was rough. Tactile signals are the positive environmental factors causing induction of the brown pupal coloration. In dark boxes, the induction of the brown pupal coloration was easily induced even on a smooth surface, suggesting that light suppresses induction of brown coloration. Different colors of pupation sites did not affect pupal coloration under sufficient light. Environmental factors received during a critical period both before girdling and after girdling affected pupal coloration. When tactile signals received from rough surfaces reach threshold levels during pupation, brown pupal coloration is determined. Larvae reared under a daily periodicity of natural light formed a girdle at midnight, subsequently, the prepupae received strong daylight the following day. Under natural light most larvae produced brown pupae on rough surfaces and green pupae on smooth surfaces.

Animals↗

PubMed1996

The use of power Doppler and color power angiography in fetal imaging.

OBJECTIVE: The potential usefulness of a new color Doppler ultrasonography technique called color power angiography in imaging fetal anatomy is presented. STUDY DESIGN: An ultrasonography system set on color power angiography was used to image fetal anatomy. Perfusion of normal organs was compared, with several fetuses demonstrating pathologic disorders of these organ systems. Color power angiography was compared with standard color Doppler imaging. RESULTS: We were able to demonstrate detailed imaging of the fetal vasculature in the lung, kidney, and brain. Abnormal lung and renal anatomy could be visualized by the distinctive perfusion "footprint." Fetal movement compromised the ability of color power angiography to visualize these structures but could be overcome by judicious use of the cineloop and persistence functions. Color power angiography was found to be more sensitive to low-flow states than was Doppler imaging. CONCLUSION: Color power angiography, which is more sensitive to low-flow states than color Doppler imaging is, may be useful in the imaging of normal and abnormal fetal anatomic structures.

Angiography↗

PubMed2005

Reversible color changes in lamella hybrids of poly(diacetylenecarboxylates) incorporated in layered double hydroxide nanosheets.

The present study is an investigation of a reversible thermal color change induced in lamella hybrids of poly(diacetylenecarboxylates) incorporated in layered double hydroxide (LDH) nanosheets. These poly-[m,n]/LDH hybrids prepared by the photo- or gamma-ray-induced polymerization of diacetylenecarboxylates, i.e., CH(3)(CH(2))(m)()(-)(1)CC-CC(CH(2))(n)()(-)(1)CO(2)(-) (mono-[m,n]), and intercalated in LDH lamella sheets, were observed to develop colors ranging from yellow to blue. The change in color was found to depend greatly on the alkyl carbon numbers of the mono-[m,n] (m,n = 10,11; 5,11; 10,5; 16,1) values. Moreover, the conformational alignment of the mono-[m,n] within the LDH was observed to be a crucial factor in color development, which was greatly affected by the intercalation degrees and extent of poly(ene-yne) linkage elongation of the polymers. For the poly-[m,n]/LDH hybrids investigated, a reversible color change was found to occur repeatedly and remarkably for the poly-[10,11]/LDH hybrid. This color change occurred at temperatures between ca. 20 and 80 degrees C back and forth from purple red to bright orange, in stark contrast to the irreversible color change for poly-[10,11] without LDH. Moreover, DSC and Raman spectroscopic studies of the LDH hybrids showed that the thermochromic temperature corresponded to the phase transition temperature of 80 degrees C. XRD analysis also indicated that the poly-[m,n]/LDH hybrid could retain its lamella structure during such thermochromic color changes, enabling conformational recovery in the polymer chains by a cooling down of the hybrids to temperatures lower than the transition temperature, while the nonhybrid poly-[10,11] powders exhibited an irreversible color change at 60 degrees C, above which the polymer powder turned amorphous.

Journal Article↗

PubMed1997

Genetic parameters for egg number, egg weight, and eggshell color in three Catalan poultry breeds.

Heritabilities for egg number, egg weight, and eggshell color (percentage light absorbance) at 39 wk of age, and the genetic correlations between them were estimated by restricted maximum likelihood in three Catalan poultry breeds: Penedesenca Negra (PN), Prat Lleonada (PL), and Empordanesa Roja (ER). Additive genetic differences between these breeds were also estimated. Data were from the IRTA Poultry Genetic Conservation Program and consisted of records from 1,309 PN, 1,466 PL, and 1,440 ER hens, which were obtained from 80 contemporary batches per breed hatched between 1987 and 1992. Estimates of heritability for egg number, egg weight, and eggshell color were, 0.20, 0.59, and 0.49 for PN, 0.31, 0.48, and 0.53 for PL; and 0.33, 0.50, and 0.27 for ER. Estimated genetic correlations between egg number and egg weight, egg number and shell color, and egg weight and shell color were, for PN, -0.22, -0.03, and 0.00; for PL, -0.21, -0.06, and 0.09; and -0.19, -0.29, and 0.30 for ER. Heritability for eggshell color and genetic correlation between eggshell color and other traits showed a different genetic pattern in ER breed. Significant additive genetic differences (P < 0.05) were found between ER and PN base populations for egg number (3.89), egg weight (0.91), and eggshell color (-3.50); and between ER and PL for egg number (6.69) and eggshell color (35.39). The PN and PL breeds differed significantly (P < 0.05) for eggshell color (38.22), which was darker in PN. These results could be taken as the expected genetic differences for these breeds.

Aging↗

PubMedDate not supplied

Color technology in video endoscopy.

The psychophysical aspects of the color experience and the clinical significance of color during video endoscopy are introduced in this paper. This introduction includes a description of how colors are rendered in video endoscope systems along with basic colorimetry, the science of color. Together these provide the clinical engineer with an understanding of color and a method of effectively communicating color information. The ability to standardize color rendition in video endoscopy systems is not yet available. Nonetheless, an argument is presented in favor of the clinical engineer normalizing color rendition in video endoscope systems in the hospital and educating the clinicians on managing endoscopic system color performance in the clinical setting.

Biomedical Engineering↗

PubMed1991

Doppler color flow image size: dependence on instrument settings.

Doppler color flow imaging provides important qualitative information about the location and spatial distribution of intracardiac blood flow. However, the effect of instrument-related variables on the size of color Doppler images requires further definition. Flow of a silicone particle solution was established in a tube or cylinder and scanned as color gain, pulse repetition frequency, depth, and transducer frequency were varied. The diameter of Doppler color flow images were measured during constant laminar or disturbed flow parallel to the ultrasound beam and during laminar flow perpendicular to the ultrasound beam. The diameter of color Doppler images of laminar flow perpendicular and parallel to the beam varied directly with color gain. Diameter varied inversely with transducer frequency for laminar flow parallel to the transducer and inversely with pulse repetition frequency for laminar flow perpendicular to the transducer. The diameter of laminar flow parallel to the transducer varied directly with the depth of the flow area below the transducer. The size of the color flow dropout of laminar flow exactly perpendicular to the ultrasound beam varied directly with transducer frequency and inversely with gain. During disturbed flow parallel to the transducer, the diameter of the image varied directly with gain and inversely with transducer frequency and pulse repetition frequency. Instrument settings have a significant impact on the size of color Doppler images. Understanding the effects of changes in these variables is important for reliable diagnostic use of Doppler color flow imaging.

Blood Flow Velocity↗

PubMed1998

Color Kinesis: Principles of Operation and Technical Guidelines.

Color kinesis is a new echocardiographic technique that aids in the assessment of global and regional left ventricular performance during either systole or diastole. Color kinesis uses automated border detection technology based on backscatter data to display both the magnitude and timing of endocardial motion in real time. The color kinesis display superimposes a color overlay on the two-dimensional echocardiographic image; the number of color pixels represents the magnitude of endocardial motion, while the different colors represent the timing of endocardial motion according to a predefined color scheme. Because color kinesis is an operator-dependent technique, the steps involved in performing a technically adequate study will be reviewed as well as the pitfalls and technical limitations. The potential clinical applications of color kinesis will also be discussed.

Journal Article↗

PubMed1991

Color velocity imaging: introduction to a new ultrasound technology.

Noninvasive ultrasound is the preferred methodology for the initial evaluation of carotid atherosclerosis. Since the early use of continuous-wave Doppler to assess carotid artery flow velocity blindly, neurosonology has progressed through crude B-mode imaging, spectral analysis of the Doppler signal, and gray-scale duplex Doppler/B-mode imaging, to color-flow Doppler duplex imaging. The latter allows color coding of Doppler data based on the velocity of blood flow. The combination of color-flow Doppler with gray-scale B-mode imaging allows simultaneous visual display of anatomical and hemodynamic information. Physical limitations of color-flow duplex Doppler imaging may affect the clinical utility of these techniques. Problems with pulse repetition frequency, aliasing, resolution capability of the color data, and interpolation of data make some applications difficult. Color velocity imaging uses the data contained in the gray-scale B-mode image scan lines to determine velocity of blood flow, and it offers potential advantages over conventional color-flow duplex Doppler for the assessment of carotid atherosclerosis and hemodynamics. Initial comparison of spectral Doppler and color velocity imaging data suggests that the latter is an accurate method to assess blood flow velocity. Understanding of the validity, utility, and prognostic advantages offered by color velocity imaging awaits careful prospective clinical trials.

Arteriosclerosis↗

PubMed1982

Long-term storage and regular repeated use of diluted antisera in glass staining jars for increased sensitivity, reproducibility, and convenience of single- and two-color light microscopic immunocytochemistry.

A procedure is described for the dilution and storage of antisera in glass staining jars into which whole slides are immersed for incubation during light microscopic neuropeptide immunocytochemistry. Diluted antisera, stored at 4 degrees C and continuously reused, were found to be stable for long periods of time (to date over 3 years), and consistently yielded high quality staining in both single- and two-color immunoperoxidase staining. We found this procedure to be more convenient than conventional incubation procedures, allowing the more rapid processing of large numbers of slides and reducing the loss of slides due to technical errors. The consistency and reproducibility of day to day staining were also improved. The immersion of whole slides into the antisera permitted the use of long incubation times (up to 7 days) without the sections drying out, which in many cases substantially enhanced the sensitivity of the staining obtained. A procedure for two-color immunoperoxidase staining is described using diaminobenzidine for a brown color and alpha-naphthol/pyronin for a red/purple color. We found the alpha-naphthol/pyronin reaction superior to the more commonly used 4-chlornaphthol reaction as a second color. The two-color staining was found useful not only for demonstrating nerve cell bodies stained different colors, but also for staining nerve terminals one color that are around and contacting nerve cell bodies stained another color.

Adrenocorticotropic Hormone↗

PubMed1989

Color Doppler ultrasound imaging of lower-extremity venous disease.

A color Doppler ultrasound imaging device was used to evaluate 475 patients with suspected lower-extremity venous thrombosis. Occlusive and nonocclusive femoral and popliteal thrombi were detected in 200 studies (42%). In phase 1 of the study (240 examinations), peripheral augmentation with the use of periodic calf compression was required to show color flow throughout the femoropopliteal venous segment. In phase 2 (235 examinations), with a software upgrade to enhance detectability of slow flow, spontaneous flow could be appreciated in the normal, partly thrombosed, and recanalized femoral popliteal veins without augmentation. Augmentation was often necessary to view tibioperoneal veins. Of the total study group, conventional venography was performed for correlation in 47 patients. In the other patients, clinicians relied on the color Doppler test for the definitive diagnosis of the presence or absence of femoral popliteal venous thrombosis and treated these patients on the basis of the color Doppler test result. In the femoral veins, color Doppler studies and venography agreed in all 12 positive and 35 negative cases. In the popliteal veins, there was agreement in five isolated popliteal thromboses and in 10 femoral popliteal thromboses; there were two false-negative color Doppler studies of isolated popliteal thromboses. In four patients, Doppler studies detected nonocclusive thrombus not evident on venography. Color Doppler imaging is easy to perform and does not require augmentation to view color flow in the femoropopliteal venous segment. Eccentric thrombus and partially canalized thrombus can be shown. Initial experience suggests color Doppler imaging may be useful in the detection of tibioperoneal venous thrombosis.

Femoral Vein↗

PubMed2003

Effects of postexsanguination vascular infusion of carcasses with calcium chloride or a solution of saccharides, sodium chloride, and phosphates on beef display-color stability.

Hereford x Angus crossbred steers (n = 36) were stunned, exsanguinated, and infused via the carotid artery either with an aqueous solution containing 98.52% water, 0.97% saccharides, 0.23% sodium chloride, and 0.28% phosphates (MPSC; n = 12) or with 0.3 M CaCl2 (n = 12). The remaining 12 steers served as noninfused controls. At 48 h postmortem, the quadriceps muscles and subcutaneous fat were removed from the carcasses, frozen, and later made into ground beef (18 to 20% fat). The longissimus lumborum (LL), semimembranosus, and psoas major (PM) also were removed, vacuum packaged, aged until 14 d postmortem, and then one steak was sliced from each muscle for visual and instrumental color evaluations. The inside (ISM) and outside (OSM) portions of the SM were evaluated separately. The LL and OSM steaks from MPSC-infused carcasses had a lighter red (P < 0.05) initial appearance than steaks from the other treatments. The LL steaks from noninfused carcasses had the most (P < 0.05) uniform color; the MPSC treatment was intermediate, and the CaCl2 treatment was the most two-toned. Steaks from both infusion treatments had higher (P < 0.05) L* values for the LL, ISM, and OSM muscles compared with noninfused carcasses. In general, the LL from CaCl2-infused carcasses had lower (P < 0.05) a* values, saturation indices, and 630 nm to 580 nm reflectance values, and had larger (P < 0.05) hue angles. Infusion with MPSC increased (P < 0.05) hue angles in the LL and OSM. Display color stability was lowest (P < 0.05) for LL steaks from CaCl2-infused carcasses, whereas steaks from MPSC-infused carcasses were lighter red in initial color, but otherwise had display color stability similar to those from noninfused carcasses. No differences (P > 0.05) due to infusion were found for any color traits for the PM muscle and ground beef. Carotid artery vascular infusion of carcasses with CaCl2 resulted in undesirable meat colors, whereas the MPSC solution lightened loin and inside round color in a desirable way, but the color stability was slightly less compared to muscle from noninfused carcasses. Infusion effects were not consistent among muscles, and further research will be needed to determine what caused these differences.

Animals↗

PubMed2006

Quantitative genetic aspects of coat color in horses.

The aim of this study was to estimate genetic parameters for coat color in horses. Besides defining coat color classes (gray, chestnut, bay, and black), the phenotypes were also measured quantitatively according to standardized international procedures (Commission Internationale de l'Eclairage L*, a*, b*), where L* describes lightness, a* describes color saturation from red to green, and b* describes color saturation from yellow to blue. The total color saturation was derived from a* and b* and referred to as Chroma. A total of 294 horses from the breeds Lipizzan, Nonius, Arabian Pure Bred, Shagya Arabian, and Gidran were measured at neck, shoulder, and belly. Heritabilities (within and between breeds or color classes) and repeatabilities were estimated using REML from univariate animal models defined separately for gray and nongray horses. For gray horses, the estimated within-breed heritabilities for L* ranged from 0.45 to 0.49 and for a*, b*, and Chroma from 0.09 to 0.52, indicating moderate polygenic effect. For nongray horses, between-color class heritabilities were high (0.70 to 0.85) and within-color class heritabilities were negligible (except for L* measured on neck and belly, 0.21 and 0.34, respectively). Additionally, the importance of L* was described by the relation with the total melanin content of horse coat hair; for gray and nongray horses, a strong negative linear relationship was detected (P < 0.01). The spectrometric measures and the results of this study demonstrate a possible approach to the estimation of the polygenic component involved in coat color inheritance.

Animals↗

PubMed1988

Effects of a hot climate on the performance of first lactation Holstein cows grouped by coat color.

Dairy Herd Improvement data from 432 Holstein cows were analyzed to determine if coat color was a significant source of variation in the performance of first lactation cows in a hot climate. One of three coat color scores was subjectively assigned to first lactation Holstein cows. White coat color was less than 40% black (15% of the cows), mixed coat color was 40 to 60% black (42% of the cows), and black coat color was greater than 60% black (43% of the cows). Coat color by season of freshening interaction was not an important source of variation for any of the production traits studied; but cows were cooled during the first 130 d of lactation, perhaps removing any advantage white cows may have had during the summer months. The interaction between coat color and season of freshening was significant for days open and services per conception. White cows freshening in February and March required fewer services per conception and had fewer open days than the mixed and black cows. The heritability estimate of coat color was .22 using a paternal half-sib analysis. Additional studies, with more white cows represented, would be useful to elucidate the effects of coat color on production in a hot climate.

Animals↗

PubMed2000

Effect of electron beam irradiation on color and microbial bioburden of red paprika.

The effect of irradiation with electron beams on the microbiological quality and color properties of red paprika was examined. The irradiation doses ranged from 0 to 12.5 kGy. The counts performed were total mesophilic aerobic microorganisms, Enterobacteriaceae, coliforms, sulfite-reducing clostridia, molds, and yeasts. It was concluded that molds, yeasts, and sulfite-reducing clostridia were the most resistant species, although a 10-kGy dose of irradiation leads to optimum sanitation. Extractable color and apparent color were analyzed to appraise the incidence of the irradiation treatments in the color properties of red paprika. Extractable color was determined according to the American Spice Trade Association method, and apparent color was analyzed by reflectance using the CIELab color space. Data showed no significant differences between the color properties of irradiated and nonirradiated samples. Irradiation was a suitable procedure to minimize the bioburden of red paprika with small modifications of its color properties.

Capsicum↗

PubMed2005

Evidence for sexual selection on structural plumage coloration in female eastern bluebirds (Sialia sialis).

Although the function of ornamental traits in males has been the focus of intensive research for decades, expression of such traits in females has received much less study. Eastern bluebirds (Sialia sialis) display structurally based ultraviolet/blue and melanin-based chestnut plumage, and in males this plumage coloration is related to both reproductive success and competitive ability. Compared to males, female bluebirds show a subdued expression of blue and chestnut ornamental coloration, and we used a combination of an aviary nutritional-stress experiment and four years of field data to test the hypothesis that coloration functions as a signal of female quality. First, we tested the effect of food intake on expression of structural and melanin coloration in female eastern bluebirds to determine whether structural or melanin coloration are condition-dependent traits. Females that were given ad libitum access to food displayed more ornamented structural coloration than females on a food-restricted diet, but there was no effect of the experiment on melanin ornamentation. Second, we used field data to assess whether female ornamentation correlated with measures of mate quality and parental effort. The structural coloration of females predicted first egg date, maternal provisioning rates, and measures of reproductive success. These data indicate that structural coloration is dependent on nutritional condition and suggest that sexual selection is acting on structurally based plumage coloration in female eastern bluebirds.

Age Factors↗

PubMed1994

[The estimation of the severity of tricuspid insufficiency by Doppler color: the effects of gain, pulse repetition frequency and the echographic view].

INTRODUCTION AND OBJECTIVES: Regurgitant jet area is to date the most widely accepted color Doppler parameter for quantitation of atrium-ventricular regurgitations. In experimental studies, it has been demonstrated that color regurgitant jet area is greatly influenced by technical settings. The present study was aimed to analyze the effect of gain setting, pulse repetition frequency and echocardiographic plane on color jet area in patients with tricuspid regurgitation. METHODS: We studied 64 patients with nontrivial (more than 1 cm2), rheumatic tricuspid regurgitation. Examinations were performed in apical four-chamber and right ventricle inflow-tract views, at two gain settings (subsaturation gain and 1/3 reduced gain) and at two pulse repetition frequencies (3.1 and 3.8 kHz). Therefore, every regurgitant jet was study under 8 different technical conditions. The remaining technical settings were held unchanged included throughout the studies. The traced area induced central varianced and aliased signals, as well as the immediately contiguous nonturbulent velocities that were moving in the same direction as the jet. Measurements were taken from 5 and 3 representative cycles in patients with atrial fibrillation and sinus rythm, respectively. RESULTS: Globally, reduction in gain setting produced a color area decrease by 50%. This reduction was of greater extent for small jets (less than 5 cm2, 45 +/- 17%) with respect to larger jets (more than 5 cm2, 61 +/- 30%, p = 0.0009). Results were similar for both apical four-chamber and right ventricle inflow views and for the two pulse repetition frequencies. At a given color gain level and echocardiographic view, pulse repetition frequency at 3.1 kHz produced greater color areas (by 3-11%) than frequency at 3.8 kHz, but the difference was not significant. Overall, color jet area was significantly greater in right ventricle inflow view than in apical four-chamber view, but substantial individual variability was observed. Difference between both views was greater than 40% in 28% of patients, with the largest color area in right ventricle inflow view in most, especially in those patients with eccentric jets. CONCLUSIONS: Gain setting and echocardiographic view greatly affect regurgitant jet area by color Doppler in patients with tricuspid regurgitation. Therefore, standardization of technical settings is mandatory in order to avoid diagnostic pitfalls.

Aged↗