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Sample records for color doppler optical

  1. In-vivo imaging of blood flow dynamics using color Doppler optical coherence tomography

    Science.gov (United States)

    Yazdanfar, Siavash; Rollins, Andrew M.; Izatt, Joseph A.

    2000-04-01

    Noninvasive quantitation of blood flow in the retinal micro circulation may elucidate the progression and treatment of ocular disorders including diabetic retinopathy, age-related degeneration, and glaucoma. Color Doppler optical coherence tomography was recently introduced as a technique allowing simultaneous micron-scale resolution cross-sectional imaging of tissue micro structure and blood flow in the human retina. Here, time-resolved imaging of dynamics of blood flow profiles was performed to measure cardiac pulsatility within retinal vessels. Retinal pulsatility has been shown to decrease throughout the progression of diabetic retinopathy.

  2. Color Doppler imaging of the retrobulbar circulation in progressive glaucoma optic neuropathy.

    Science.gov (United States)

    Magureanu, Marineta; Stanila, Adriana; Bunescu, Liviu Valentin; Armeanu, Cristina

    2016-01-01

    It is known that elevated intraocular pressure (IOP) is the primary risk factor for glaucoma. Recently, more and more evidences have shown that the vascular deficit also plays an important role in the pathogenesis and progressions of glaucomatous optic neuropathy. This issue is backed up by glaucomatous optic neuropathy (GON) cases drug compensated in which the progression of the disease in one or both eyes is ascertained despite a normal and relatively constant IOP. The present study evaluated the hemodynamic parameters in the retrobulbar circulation in patients with progressive glaucomatous optic neuropathy in one eye, who received compensated medication. The hemodynamic parameters (PSV, EDV, IR) were measured by using color Doppler ultrasound and progression was evaluated by a repeated automated perimetry. The obtained values were statistically analyzed and compared with those obtained for the stable eye.

  3. High-flow-velocity and shear-rate imaging by use of color Doppler optical coherence tomography

    NARCIS (Netherlands)

    van Leeuwen, T. G.; Kulkarni, M. D.; Yazdanfar, S.; Rollins, A. M.; Izatt, J. A.

    1999-01-01

    Color Doppler optical coherence tomography (CDOCT) is capable of precise velocity mapping in turbid media. Previous CDOCT systems based on the short-time Fourier transform have been limited to maximum flow velocities of the order of tens of millimeters per second. We describe a technique, based on

  4. In-vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography

    Science.gov (United States)

    Yazdanfar, Siavash; Rollins, Andrew M.; Izatt, Joseph A.

    1999-04-01

    Quantification of retinal blood flow may lead to a better understanding of the progression and treatment of several ocular disorders, including diabetic retinopathy, age- related macular degeneration, and glaucoma. Current techniques, such as fluorescein angiography and laser Doppler velocimetry are limited, failing to provide sufficient information to the clinician. Color Doppler optical coherence tomography (CDOCT) is a novel technique using coherent heterodyne detection for simultaneous cross- sectional imaging of tissue microstructure and blood flow. This technique is capable of high spatial and velocity resolution imaging in highly scattering media. We implemented CDOCT for retinal blood flow mapping in human subjects. No dilation of the pupil was necessary. CDOCT is demonstrated for determining bidirectional flow in sub- 100micrometers diameter vessels in the retina. Additionally, we calculated Doppler broadening using the variance of depth- resolved spectra to identify regions with large velocity gradients within the Xenopus heart. This technique may be useful in quantifying local tissue perfusion in highly vascular retinal tissue.

  5. Color doppler sonography in thickened gallbladder wall

    International Nuclear Information System (INIS)

    Han, Sang Suk; Choi, Seok Jin; Seo, Chang Hae; Eun, Choong Ki

    1996-01-01

    The thickening of the gallbladder wall is a valuable finding for the diagnosis of cholecystitis, but may be seen in non-cholecystic disease as well as in acute or chronic cholecystitis. The purpose of this study is to determine the value of color Doppler sonography in differentiating the causes of thickened gallbladder wall. Ninety eight patients with thickened gallbladder wall(more than 3mm) which was not due to gallbladder cancer were prospectively evaluated with color Doppler sonography. Sixty-six cases, confirmed by pathologic reports and clinical records, were analyzed for correlation between thickened gallbladder wall and color flow signal according to the underlying causes. Of the 66 patients, 28 cases were cholecystitis and 38 cases had non-cholecystic causes such as liver cirrhosis, ascites, hepatitis, pancreatitis, renal failure, and hypoalbuminemia. Of the 28 patients with cholecystitis(12 acute, 16 chronic), 23(82%) had color Doppler flow signals in the thickened gallbladder wall. Of the 38 patients with non-cholecystic causes, eight(21%) had color Doppler flow signals. There was a statistically significant difference of color Doppler flow signals between the cholecystitis and non-cholecystic groups(p=0.0001). No significant difference of color Doppler flow signals was found between cases of acute and chronic cholecystitis. Of the 23 patients with color Doppler flow signals in 28 cases of cholecystitis, 18(78.3%) showed a linear pattern and five(21.7%) showed a spotty pattern. Of the eight patients with color Doppler flow signals in the 38 non-cholecystic cases, four(50%) showed a linear pattern and four(50%) showed a spotty pattern. In cholecystitis, a linear color Doppler flow signal pattern is a much more frequent finding than a spotty pattern. Color Doppler sonography is a useful and adequate method for determining whether a thickened gallbladder wall is the result of cholecystitis or has non-cholecystic causes

  6. Color doppler imaging of subclavian steal phenomenon

    International Nuclear Information System (INIS)

    Cho, Nari Ya; Chung, Tae Sub; Kim, Jai Keun

    1997-01-01

    To evaluate the characteristic color doppler imaging of vertebral artery flow in the subclavian steal phenomenon. The study group consisted of eight patients with reversed vertebral artery flow proved by color Doppler imaging. We classified this flow into two groups:(1) complete reversal;(2) partial reversal, as shown by Doppler velocity waveform. Vertebral angiography was performed in six of eight patients;color Doppler imaging and angiographic findings were compared. On color Doppler imaging, all eight cases with reversed vertebral artery flow showed no signal at the proximal subclavian or brachiocephalic artery. We confirmed shunting of six cases by performing angiography from the contralateral vertebral and basilar artery to the ipsilateral vertebral artery. On the Doppler spectrum, six cases showed complete reversal and two partial reversal. On angiography, one partial reversal case showed complete occlusion of the subclavian artery with abundant collateral circulation of muscular branches of the vertebral artery. On color Doppler imaging, a reversed vertebral artery suggests the subclavian steal phenomenon. In particular, partial reversal waveform may reflect collateral circulation

  7. Ultrasonic Doppler color in glaucoma: Concordance study

    International Nuclear Information System (INIS)

    Uriza, Felipe; Useche, Nicolas

    2005-01-01

    Our study demonstrates that US color Doppler is a non invasive, reliable and reproducible method for the evaluation of the orbitary flow in normal and glaucomatous patients. However is suggested that every group evaluates the inter and intraobserver variability because of the lack of universal reference velocity measurements

  8. Color Doppler Ultrasonographic Features of Hashimoto's Thyroiditis

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    Lee, Joo Hyuk; Kim, Mie Young; Rho, Eun Jin; Yi, Jeong Geun; Han, Chun Hwan [Kangnam General Hospital Public Corporation, Seoul (Korea, Republic of); Hwang, Hee Yong [Choong Ang Gil Hospital, Incheon (Korea, Republic of)

    1995-06-15

    Color Doppler ultrasonographic(US) features of 28 patients with Hashimato's thyroiditis were evaluated with regard to echo and color-flow patterns. Correlation of color-flow pattern with thyroid function was performed. All 28 patients showed varying degrees of diffuse enlargement of the thyroid gland and a heterogeneous echo pattern.Color-flow pattern of increased blood flow. Low to moderate, focally increased blood flow was seen in 26 patients(92.8%). Of these 26 patients, 24 patients showed subclinical hypothyroidism or euthyroidism. Two patients who showed hyperthyroidism showed several pieces of focally increased color flow, Which was noted during both systole and diastole. Diffuse, multifocal color-flow throughout thyroid gland was seen in two patients with Hashimato's thyroiditis: one with clinical hypothyroidism and the other with subclinical hypothyroidism. Even though Hashimoto's thyroiditis showed variable color-flow patterns, we believe that heterogenous parenchymal echopattern with low or moderately increased flow is a rather characteristic feature of Hashimoto's thyroiditis, and we suggest that color Doppler US provides additional information for evaluation of Hashimoto's thyroiditis

  9. Color Doppler Ultrasonographic Features of Hashimoto's Thyroiditis

    International Nuclear Information System (INIS)

    Lee, Joo Hyuk; Kim, Mie Young; Rho, Eun Jin; Yi, Jeong Geun; Han, Chun Hwan; Hwang, Hee Yong

    1995-01-01

    Color Doppler ultrasonographic(US) features of 28 patients with Hashimato's thyroiditis were evaluated with regard to echo and color-flow patterns. Correlation of color-flow pattern with thyroid function was performed. All 28 patients showed varying degrees of diffuse enlargement of the thyroid gland and a heterogeneous echo pattern.Color-flow pattern of increased blood flow. Low to moderate, focally increased blood flow was seen in 26 patients(92.8%). Of these 26 patients, 24 patients showed subclinical hypothyroidism or euthyroidism. Two patients who showed hyperthyroidism showed several pieces of focally increased color flow, Which was noted during both systole and diastole. Diffuse, multifocal color-flow throughout thyroid gland was seen in two patients with Hashimato's thyroiditis: one with clinical hypothyroidism and the other with subclinical hypothyroidism. Even though Hashimoto's thyroiditis showed variable color-flow patterns, we believe that heterogenous parenchymal echopattern with low or moderately increased flow is a rather characteristic feature of Hashimoto's thyroiditis, and we suggest that color Doppler US provides additional information for evaluation of Hashimoto's thyroiditis

  10. Color Doppler US of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Bertolotto, Michele (ed.) [Trieste Univ. Ospedale di Cattinara (Italy). Dept. Radiology

    2008-07-01

    This book provides a comprehensive reference and practical guide on the application of US to penile diseases and conditions. After introductory chapters on technical requirements and penile anatomy, subsequent chapters offer a systematic overview of the diverse applications of color Doppler US. The topics covered include erectile dysfunction, Peyronie's disease, priapism, trauma, tumors, the postoperative penis, inflammation, and fibrosis. Each topic is introduced by a clinical overview with the purpose of clarifying the problems and elucidating what the urologist may expect from color Doppler US. Thereafter, performance of the US study is explained and the pathological anatomy reviewed. High-quality images obtained with high-end US equipment are included. Each chapter also contains a section on the diagnostic information provided by other imaging modalities, and in particular MRI. (orig.)

  11. OCT angiography and Color Doppler Imaging in the study of hemoperfusion in the retina and optic nerve in POAG

    Directory of Open Access Journals (Sweden)

    N. I. Kurysheva

    2016-01-01

    Full Text Available Purpose: To evaluate the hemoperfusion of Optic Nerve Disk (OND, peripapillary and macular areas, and retrobulbar blood flow in patients with primary open-angle glaucoma using optical coherence tomography with angiography (OCT-A and Сolor Doppler Imaging (CDI.Patients and Methods: 65 eyes of patients with primary open angle glaucoma (POAG and 22 eyes of age-matched healthy subjects were examined using the SD-OCT-А (RtVue xR Avanti with the AngioVue software. Retinal Thickness and Angio Flow Density (AFD were measured. AFD Disc and Peripapillary Flow Density were measured in OND and in peripapillary area. AFD Retina were evaluated in Macula inсluding Fovea- and Parafovea regions (superficial and deep of the inner retinal layers. Ophthalmic Artery (OA, Central Retinal Artery (CRA, Posterior short Ciliary Arteries (PCA, Central Retinal Vein (CRV and Vortex Vein (VV were measured by CDI. Statistical analysis was performed using SPSS version 21 and MASS library of language R. The value of each diagnostic indicator (z-value was calculated with the Wilcoxon-Mann-Whitney test and the area under the receiver operating characteristic curve (AUC.Results: Both OCT-A and CDI indicators were reduced in glaucoma compared to healthy eyes. The following indicators had the largest AUC and diagnostic value (z-value to discriminate the early glaucoma from normal eyes: AFD Retina Superficial Whole En Face (z = 3,83, p<0,0001; AUC 0,8 (0,69‑0,90, AFD Retina Deep Whole En Face (z = 3,31, p = 0,0007; AUC 0,76 (0,64‑0,88, Peripapillary Vessel Density (z = 3,2, p = 0,001; AUC 0,75 (0,63‑0,87, end-diastolic flow velocity in AO (z = 3,03, p = 0,002; AUC 0,74 (0,61‑0,86 and in TPCA (z = 2,78, p = 0,005; AUC 0,72 (0,58‑0,86; and to discriminate the early glaucoma from the advanced and far advanced stages: AFD Disc Peripapillary Inferior Temporalis (z = 5,61, p<0,0001; AUC 0,94 (0,86‑1,0 and the mean flow velocity in the CRA (z = 4,16, p<0

  12. Power and color Doppler ultrasound settings for inflammatory flow

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin

    2015-01-01

    OBJECTIVE: To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. METHODS: Six different types of ultrasound machines were used....... On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA......) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity. RESULTS...

  13. Evaluating Peripheral Vascular Injuries: Is Color Doppler Enough for Diagnosis?

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    Mohd Lateef Wani

    2014-03-01

    Full Text Available Background:: Vascular injury poses a serious threat to limb and life. Thus, diagnosis should be made immediately with minimally invasive methods. Doppler is a good aid in diagnosis of vascular injury. Methods:: The present prospective study was conducted on 150 patients who presented with soft signs (the signs which are suggestive but not confirmatory of vascular injury. They were subjected to color Doppler examination before exploration. The patients with the features of vascular injury on color Doppler were subjected to exploration. On the other hand, those who had normal Doppler were subjected to CT- angiography. Then, the findings of the exploration were matched with those of color Doppler. The data were analyzed using the SPSS statistical software. Results:: Out of the 150 Doppler examinations, 110 (73.33% were reported as positive, while 40 were reported as negative for vascular injury. These were subjected to CT-angiography and seven of them had the features of vascular injury on CT-angiography. All the patients with positive Doppler or CT angiography findings were subjected to exploration. Doppler had a sensitivity of 94% and specificity of 82.5% in diagnosis of vascular injury using Binary classification test. Conclusions:: Color Doppler is an easily available, reliable, and handy method of diagnosing a vascular injury. It has a very high sensitivity and specificity in diagnosis of vascular injuries.

  14. Color doppler ultrasound diagonosis in cesarean scar pregnancy

    International Nuclear Information System (INIS)

    Chen Shanshan; Xia Fei; Shen Zongji; Xu Jianyin; Gu Xinxian

    2010-01-01

    Objective: To study the sonographic characteristics of cesarean scar pregnancy(CSP), and the value of color Doppler in the diagnosis of CSP. Methods: Twelve cases of CSP were all confirmed by transabdominal and transvaginal ultrasound. Results: The ultrasonogram of CSP could be divided into gestational sac type and mixed mass type. Conclusion: Color Doppler can give guidance to the early diagnosis, treatment and following-up of CSP because of the sonographic specifity of CSP. (authors)

  15. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Science.gov (United States)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    Aim: To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions. PMID:22223940

  16. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    International Nuclear Information System (INIS)

    Goel, Sumit; Nagendrareddy, Suma Gundareddy; Raju, Manthena Srinivasa; Krishnojirao, Dayashankara Rao Jingade; Rastogi, Rajul; Mohan, Ravi Prakash Sasankoti; Gupta, Swati

    2011-01-01

    To evaluate the efficacy of ultrasonography (USG) with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas) of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas). There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions

  17. Ultrasonography with color Doppler and power Doppler in the diagnosis of periapical lesions

    Directory of Open Access Journals (Sweden)

    Sumit Goel

    2011-01-01

    Full Text Available Aim: To evaluate the efficacy of ultrasonography (USG with color Doppler and power Doppler applications over conventional radiography in the diagnosis of periapical lesions. Materials and Methods: Thirty patients having inflammatory periapical lesions of the maxillary or mandibular anterior teeth and requiring endodontic surgery were selected for inclusion in this study. All patients consented to participate in the study. We used conventional periapical radiographs as well as USG with color Doppler and power Doppler for the diagnosis of these lesions. Their diagnostic performances were compared against histopathologic examination. All data were compared and statistically analyzed. Results: USG examination with color Doppler and power Doppler identified 29 (19 cysts and 10 granulomas of 30 periapical lesions accurately, with a sensitivity of 100% for cysts and 90.91% for granulomas and a specificity of 90.91% for cysts and 100% for granulomas. In comparison, conventional intraoral radiography identified only 21 lesions (sensitivity of 78.9% for cysts and 45.4% for granulomas and specificity of 45.4% for cysts and 78.9% for granulomas. There was definite correlation between the echotexture of the lesions and the histopathological features except in one case. Conclusions: USG imaging with color Doppler and power Doppler is superior to conventional intraoral radiographic methods for diagnosing the nature of periapical lesions in the anterior jaws. This study reveals the potential of USG examination in the study of other jaw lesions.

  18. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

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    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee [Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Kim, Sam Soo [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2009-12-15

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  19. Color Doppler Ultrasonographic Findings of Vascular Leiomyoma: Pathologic Correlation

    International Nuclear Information System (INIS)

    Ko, Ji Young; Koh, Sung Hye; Min, Soo Kee; Choi, A Lam; Jang, Kyung Mi; Lee, Yul; Lee, Kwan Seop; Lee, Hyun; Sohn, Jeong Hee; Kim, Sam Soo

    2009-01-01

    To evaluate the distribution of color flow signals on color Doppler ultrasonography of vascular leiomyomas and to correlate them with pathologic findings. We retrospectively analyzed color Doppler ultrasonographic images and pathologic slides of six vascular leiomyomas. We classified the patterns of distribution of color flow signals into localized compact cluster types and non-cluster types, and the pathologic findings into three subtypes: solid, venous and cavernous. All cases showed well-defined homogenous hypoechoic subcutaneous masses on gray-scale ultrasonography. Three cases showed localized compact cluster types on color Doppler ultrasonography, one in each subtype (solid, venous and cavernous). For the three non-cluster types, again there was on in each subtype. In addition, on pathologic analysis the zone of the localized compact cluster of color flow signals coincided with a cluster of larger, vascular caliber masses. Localized compact clusters of color flow signals on color Doppler ultrasonography were seen in 50% of our cases and correlated with a cluster of larger vascular caliber in the mass. But the pattern of distribution of color flows didn't show a correlation with pathologic type

  20. Gallblader varices in children with portal cavernoma: duplex-Doppler and color Doppler ultrasound studies

    International Nuclear Information System (INIS)

    Muro, D.; Sanguesa, C.; Lopez, A.

    1998-01-01

    To determine the prevalence of varices in the gallbladder wall, observed by duplex-Doppler and color Doppler ultrasound, in children with cavernoma of the portal vein. Nineteen patients with portal hypertension were studied prospectively by duplex-Doppler and color Doppler ultrasound: 12 of the patients had developed a cavernoma of the portal vein. The presence of peri vesicular varices was assessed in the group of patients with portal cavernoma. Duplex-Doppler and color Doppler ultrasound disclosed the presence of varices in gallbladder wall in nine of the 12 patients (75%). The varices appeared as anechoic and serpiginous areas, and Doppler ultrasound revealed slowed venous flow. However, the three patients in whom gallbldder varices were not detected presented collateral gastric ciculation and spontaneous splenorenal shunt. Gallbladder varices are common in children with portal vein cavernoma; they present hepatopetal flow. Their developments is not related to the size of the portal cavernoma, the presence of spontaneous portosystemic shunts, or endoscopic obliteration of gastric and esophageal varices. The detection of gallbladder varices in patients with portal hypertension who are to undergo biliary surgery is highly important for the surgeon, helping to avoid perioperative complications. (Author) 15 refs

  1. Comparison of power Doppler and color Doppler ultrasonography in the detection of intrasticular blood flow of normal infants

    International Nuclear Information System (INIS)

    Shin, Sung Ran; Lee, Ho Kyoung; Lee, Won Gyun; Youk, Dong Joon; Rho, Taek Soo; Lee, Min Jin; Lee, Sang Chun

    1999-01-01

    To compare color Doppler ultrasonography (US) and power Doppler US in the detection of intratesticular blood flow in normal infants and to asses the symmetry of blood flow. Testicular blood flow was assessed prospectively in 100 testes of 50 infants with both power and color Doppler US. We compared the power Doppler with color Doppler to detect intratesticular blood. When the flow was detected, intratesticular blood flow was graded as follows: grade 1: single intratesticular Doppler signal ; grade 2: multiple intratesticular Doppler signals. The symmetry of intratesticular flow was assessed by using the same method. Intratesticular flow was detected in 72 (72%) and 68 (68%) testes on power and color Doppler US, respectively. In 76 testes (76%), intratesticular flow was detected in either one or both techniques. On power Doppler US, grade 1 was seen in 40 tests and grade 2 in 32 testes. On color Doppler US, grade 1 was noted in 52 testes and grade 2 in 16 testes. Testicular blood flow was symmetric on both power and color Doppler US in each patient. There was no difference between power Doppler and color Doppler ultrasonography in detecting intratesticular blood flow in normal infants.

  2. Temporal enhancement of two-dimensional color doppler echocardiography

    Science.gov (United States)

    Terentjev, Alexey B.; Settlemier, Scott H.; Perrin, Douglas P.; del Nido, Pedro J.; Shturts, Igor V.; Vasilyev, Nikolay V.

    2016-03-01

    Two-dimensional color Doppler echocardiography is widely used for assessing blood flow inside the heart and blood vessels. Currently, frame acquisition time for this method varies from tens to hundreds of milliseconds, depending on Doppler sector parameters. This leads to low frame rates of resulting video sequences equal to tens of Hz, which is insufficient for some diagnostic purposes, especially in pediatrics. In this paper, we present a new approach for reconstruction of 2D color Doppler cardiac images, which results in the frame rate being increased to hundreds of Hz. This approach relies on a modified method of frame reordering originally applied to real-time 3D echocardiography. There are no previous publications describing application of this method to 2D Color Doppler data. The approach has been tested on several in-vivo cardiac 2D color Doppler datasets with approximate duration of 30 sec and native frame rate of 15 Hz. The resulting image sequences had equivalent frame rates to 500Hz.

  3. Acute intrascrotal pathology in childhood: color Doppler study

    International Nuclear Information System (INIS)

    Cinta Sanguesa, C.; Muro, D.; Cortina, H.; Moreno, A.

    1997-01-01

    To asses the utility of color Doppler ultrasound in the study of acute intrascrotal pathology in childhood. Seventy-five boys with evidence of an acute intrascrotal abnormality were studied by means of color Doppler ultrasound. A 7.5 MHz linear transducer was used. The most common findings was inflammatory disease (60%) which was indicated by the presence of hyperemia in color Doppler. Of the nine boys with testicular torsion (12%) two presented extravaginal torsion, with a complete absence of intratesticular vascularization. Intravaginal torsion was observed in seven patients, six of whom presented reduced vascularization in the abnormal testicle with respect to the healthy testicle. There was one false negative in which testicular vascularization was normal but 360 degree centigree torsion was found at surgery. In addition, there were seven cases of hydatid torsion (9.33%), four of idiopathic scrotal swelling (5.3%). two cases of intermittent torsion (2.6%) and one case of Shcolein-Henoch purpura (1.3%). The ultrasound findings were completely nornal in seven boys. Color Doppler is a rapid, noninvasive method for assessing testicular blood flow. The elevated sensitivity and specificity (85.7 and 100%, respectively, in our series) for testicular torsion make Doppler ultrasound a highly reliable method for the study of this disorder. (Author) 18 refs

  4. Prenatal color Doppler ultrasonographic diagnosis of fetal tetralogy of Fallot

    International Nuclear Information System (INIS)

    Tan Buqiao

    2009-01-01

    Objective: To investigate the sonographic findings of tetralogy of Fallot in fetuses. Methods: The data of color Doppler ultrasonography and follow-up results of 5 fetal tetralogy of Fallot were analyzed retrospectively, and their abnormal ultrasound imaging characteristic were summarized. Results: Two cases were proved tetralogy of Fallot by autopsy, and three cases were confirmed to be tetralogy of Fallot by echocardiography after birth. The image features were the main aorta situated above the ventricular septal defect, pulmonary stenosis, no obvious thickening of the right wall. Conclusion: Fetal tetralogy of Fallot have characteristic ultrasound images, prenatal color Doppler ultrasonographic can diagnoses fetal tetralogy of Fallot correctly and has important clinical value. (authors)

  5. Gestational trophoblastic neoplasia: efficacy of color doppler ultrasound

    International Nuclear Information System (INIS)

    Song, Sun Wha; Jee, Won Hee; Choe, Bo Young; Byun, Jae Young; Choi, Byung Gil; Shinn, Kyung Sub

    1997-01-01

    To evaluate the efficacy of color Doppler ultrasound (US) in the diagnosis of gestational trophoblastic neoplasia (GTN). Intralesional color flows and resistive index (RI) on color Doppler US were prospectively analyzed in 21 consecutive suspected GTN cases. RI of the intralesional artery was investigated on the basis of the presence or absence of mass and metastasis. Correlation between RI of intralesional artery and urinary β-hCG was also investigated. Intralesional color flows were identified in 15 patients with GTN. On operation, intralesional color flows were observed in one of two patients in whom the presence of completely necrotic tissue was confirmed. Intralesional color flows, however, were not detected in four patients who were proved not to be GTN sufferers. Sensitivity, specificity, accuracy, positive and negative predictive values, and accuracy were 100%, 83%, 95%, 94% and 100%, respectively. Significant correlation between RI of the intralesional artery and urinary β-hCG was not established (p=0.49, r=0.19). RI of this artery was not substantially different between groups with and without mass, and between groups with and without metastasis (p=0.32, p=0.82). The current study demonstrates that color Doppler US is a sensitive and useful method for the diagnosis of GTN

  6. Color Doppler Echocardiographic Assessment of Valvular Regurgitation in Normal Infants

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    Shu-Ting Lee

    2010-01-01

    Conclusion: The prevalence of inaudible valvular regurgitation is high in infants with structurally normal hearts. Multiple-valve involvement with regurgitation is not uncommon. Mild severity and low velocity on color Doppler, and the structural information provided by 2D imaging strongly suggest that these regurgitant flows are physiologically normal in infancy.

  7. Ultrasonography and color Doppler in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2011-01-01

    hypertrophy, effusion) and by color Doppler (synovial hyperemia) before and 4 weeks after US-guided steroid injection. Results US detected 121 compartments with active disease (joints, tendon sheaths and 1 ganglion cyst). Multiple compartments were involved in 80% of the ankle regions. The talo-crural joint...

  8. Color M-mode and pulsed wave tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Poulsen, S H

    2001-01-01

    To assess the association between color M-mode flow propagation velocity and the early diastolic mitral annular velocity (E(m)) obtained with tissue Doppler echocardiography and to assess the prognostic implications of the indexes, echocardiography was performed on days 1 and 5, and 1 and 3 month...

  9. Role of color Doppler ultrasound in the diagnosis of nonpalpable ...

    African Journals Online (AJOL)

    excluded from the study. Color Doppler was performed in all cases, followed by laparoscopy. Further, findings on laparoscopy were compared with those of CDUS. A 95% confidence interval for the sensitivity of CDUS was estimated considering a positive result on CDUS as the binomial variable. Results. Out of 25 patients, ...

  10. Color Doppler Ultrasonographic Features of Hashimoto's Thyroiditis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo Hyuk; Kim, Mie Young; Rho, Eun Jin; Yi, Jeong Geun; Han, Chun Hwan [Kangnam General Hospital Public Corporation, Seoul (Korea, Republic of); Hwang, Hee Yong [Choong Ang Gil Hospital, Incheon (Korea, Republic of)

    1995-06-15

    Color Doppler ultrasonographic(US) features of 28 patients with Hashimato's thyroiditis were evaluated with regard to echo and color-flow patterns. Correlation of color-flow pattern with thyroid function was performed. All 28 patients showed varying degrees of diffuse enlargement of the thyroid gland and a heterogeneous echo pattern.Color-flow pattern of increased blood flow. Low to moderate, focally increased blood flow was seen in 26 patients(92.8%). Of these 26 patients, 24 patients showed subclinical hypothyroidism or euthyroidism. Two patients who showed hyperthyroidism showed several pieces of focally increased color flow, Which was noted during both systole and diastole. Diffuse, multifocal color-flow throughout thyroid gland was seen in two patients with Hashimato's thyroiditis: one with clinical hypothyroidism and the other with subclinical hypothyroidism. Even though Hashimoto's thyroiditis showed variable color-flow patterns, we believe that heterogenous parenchymal echopattern with low or moderately increased flow is a rather characteristic feature of Hashimoto's thyroiditis, and we suggest that color Doppler US provides additional information for evaluation of Hashimoto's thyroiditis

  11. Choroid metastasis of papillary thyroid carcinoma. Color doppler ultrasound study

    International Nuclear Information System (INIS)

    Ganado, T.; Torre, S. de la; Contreras, E.; Hernandez, J.

    1997-01-01

    The most common causes of intraocular metastases are breast and lung cancers, although many other neoplasms can metastasize to the eye. Most of the metastases are located in the posterior pole and the choroid is more often involved than the retina. We present a case of a choroidal metastasis from a papillary carcinoma of the thyroid, associated with a massive subretinal hemorrhage. Findings with color Doppler ultrasound are emphasized. (Author) 9 refs

  12. Complex regression Doppler optical coherence tomography

    Science.gov (United States)

    Elahi, Sahar; Gu, Shi; Thrane, Lars; Rollins, Andrew M.; Jenkins, Michael W.

    2018-04-01

    We introduce a new method to measure Doppler shifts more accurately and extend the dynamic range of Doppler optical coherence tomography (OCT). The two-point estimate of the conventional Doppler method is replaced with a regression that is applied to high-density B-scans in polar coordinates. We built a high-speed OCT system using a 1.68-MHz Fourier domain mode locked laser to acquire high-density B-scans (16,000 A-lines) at high enough frame rates (˜100 fps) to accurately capture the dynamics of the beating embryonic heart. Flow phantom experiments confirm that the complex regression lowers the minimum detectable velocity from 12.25 mm / s to 374 μm / s, whereas the maximum velocity of 400 mm / s is measured without phase wrapping. Complex regression Doppler OCT also demonstrates higher accuracy and precision compared with the conventional method, particularly when signal-to-noise ratio is low. The extended dynamic range allows monitoring of blood flow over several stages of development in embryos without adjusting the imaging parameters. In addition, applying complex averaging recovers hidden features in structural images.

  13. Doppler optical cardiogram gated 2D color flow imaging at 1000 fps and 4D in vivo visualization of embryonic heart at 45 fps on a swept source OCT system.

    Science.gov (United States)

    Mariampillai, Adrian; Standish, Beau A; Munce, Nigel R; Randall, Cristina; Liu, George; Jiang, James Y; Cable, Alex E; Vitkin, I A; Yang, Victor X D

    2007-02-19

    We report a Doppler optical cardiogram gating technique for increasing the effective frame rate of Doppler optical coherence tomography (DOCT) when imaging periodic motion as found in the cardiovascular system of embryos. This was accomplished with a Thorlabs swept-source DOCT system that simultaneously acquired and displayed structural and Doppler images at 12 frames per second (fps). The gating technique allowed for ultra-high speed visualization of the blood flow pattern in the developing hearts of African clawed frog embryos (Xenopus laevis) at up to 1000 fps. In addition, four-dimensional (three spatial dimensions + temporal) Doppler imaging at 45 fps was demonstrated using this gating technique, producing detailed visualization of the complex cardiac motion and hemodynamics in a beating heart.

  14. Study of retrobulbar hemodynamics in diabetes via color doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2014-09-01

    Full Text Available AIM: To explore the changes of retrobulbar hemodynamics in diabetes via color doppler ultrasound. METHODS: Totally 80 patients(160 eyeswith eye diseases in type 2 diabetes from June 2010 to May 2013 in our hospital were enrolled as research group. By fundus photography and direct ophthalmoscopy, patients were assigned to diabetes without retinopathy group(DNR subgroup, non-proliferative diabetic retinopathy group(NPDR subgroupand proliferative diabetic retinopathy group(PDR subgroup. Of 60 healthy patients(120 eyesover the same period were chosen as control group. The doppler parameters of central retinal artery(CRA, posterior ciliary artery(PCAand ophthalmic artery(OAwere measured.RESULTS: There were significant differences on circulatory parameters of CRA, PCA and OA between both groups(PPPCONCLUSION: The monitoring of retinal blood flow and analysis of blood spectrum morphology via color doppler ultrasound can effectively evaluate the degree of diabetic retinopathy lesions, especially before DR vascular disease. Early detection can reveal the hemodynamic change pattern of DR, facilitating the prevention of diabetic eye complications and improvement of the quality of life.

  15. [Current role of color Doppler ultrasound in acute renal failure].

    Science.gov (United States)

    Bertolotto, M; Quaia, E; Rimondini, A; Lubin, E; Pozzi Mucelli, R

    2001-01-01

    Acute Renal Failure (ARF) is characterized by a rapid decline of the glomerular filtration rate, due to hypotension (prerenal ARF), obstruction of the urinary tract (post-renal ARF) or renal parenchymal disease (renal ARF). The differential diagnosis among different causes of ARF is based on anamnesis, clinical symptoms and laboratory data. Usually ultrasound (US) is the only imaging examination performed in these patients, because it is safe and readily available. In patients with ARF gray scale US is usually performed to rule out obstruction since it is highly sensitive to recognize hydronephrosis. Patients with renal ARF have no specific changes in renal morphology. The size of the kidneys is usually normal or increased, with smooth margins. Detection of small kidneys suggests underlying chronic renal pathology and worse prognosis. Echogenicity and parenchymal thickness are usually normal, but in some cases there are hyperechogenic kidneys, increased parenchymal thickness and increased cortico-medullary differentiation. Evaluation of renal vasculature with pulsed Doppler US is useful in the differential diagnosis between prerenal ARF and acute tubular necrosis (ATN), and in the diagnosis of renal obstruction. Latest generation US apparatus allow color Doppler and power Doppler evaluation of renal vasculature up to the interlobular vessels. A significant, but non specific, reduction in renal perfusion is usually appreciable in the patients with ARF. There are renal pathologic conditions presenting with ARF in which color Doppler US provides more specific morphologic and functional information. In particular, color Doppler US often provides direct or indirect signs which can lead to the right diagnosis in old patients with chronic renal insufficiency complicated with ARF, in patients with acute pyelonephritis, hepatic disease, vasculitis, thrombotic microangiopathies, and in patients with acute thrombosis of the renal artery and vein. Contrast enhanced US is

  16. Color doppler energy (CDE) : initial ten-months experience

    International Nuclear Information System (INIS)

    Ro, Young Jin; Son, Hyun Ju; Lee, Suck Hong; Kim, Byung Soo; Han, Kook Sang; Nam, SAng Hwa; Lee, Keum Seob; Shin Se Kwon

    1996-01-01

    Color Doppler imaging(CDI) has shortcomings, including random noise, aliasing, and angle dependence. To overcome these, a method using CD US, termed power doppler or Color Doppler Energy(CDE), has recently been introduced. The purpose of this study was to show the clinical usefulness of CDE. We retrospectively analyzed the CDI and CDE of 61 cases(20 renal pseudotumors, 8 musculoskeletal inflammations, 17 epididymitis or epididymo-orchitis, 3 varicoceles, 1 normal testis, 1 hepatocellualr carcinoma, 7 renal cell carcinoma, 1 renal angiomyolipoma, and 3 splenic varices). CDI and CDE scans were obtained at the same region with constant scan plane. The color gain was increased until noise first became perceptible, and scans were always obtained in such a way that the maximum amount of vascularity was shown. Thereafter, the vascularity, vascular displacement, and the vascular relationship between CDI and CDE were compared. In 17 of 20 cases of pseudotumor in the kidney, normal vascularity was identified in CDI and CDE, but was more cleary visible in CDE. In three cases, there was no visible vascularity in CDI, but normal vascularity in CDE. In eight cases of musculoskeletal inflammation and 17 cases of epididymitis with or without orchitis, the vascularity was increased due to hyperemia, which was more prominently seen in CDE than in CDI. In three varicoceles, CDE appeared to be better in demonstrating low velocity flow. In one patient who was suspected of having acute testicular torsion, CDE was helpful in excluding this suspicion. In one case of hepatocellualr carcinoma, seven cases of renal cell carcinoma, one case of renal angiomyolipoma, and three cases of splenic varices, CDE was better than CDI in showing the vascularity, vascular relationship, and vascular displacement

  17. Color-flow Doppler imaging in suspected extremity venous thrombosis

    International Nuclear Information System (INIS)

    Foley, W.D.; Middleton, W.D.; Lawson, T.L.; Hinson, G.W.; Puller, D.R.

    1987-01-01

    Color-flow Doppler imaging (CFDI) (Quanatum, 5 and 7.5 MHz, linear array) has been performed on 23 extremities (nine positive for venous thrombosis, 14 negative) with venographic correlation. CFDI criteria evaluated were venous color-flow respiratory variation, augmentation, compressibility, valve competence, and intraluminal echogenic filling defects. Both CFDI and venography were evaluated independently and prospectively. CFDI and venography agreed in all six cases of femoral vein thrombosis and eight of nine cases of popliteal vein thrombosis. CFDI was negative in one instance of recanalized popliteal vein thrombosis. Recanalized femoral vein thrombosis was documented in three patients by CFDI when the vein was nonopacified on conventional venography. CFDI provides a rapid and accurate assessment of the femoral popliteal venous system and can distinguish an occluded from a recanalized thrombus. Initial experience with auxiliary subclavian venous thrombus has produced equally accurate results

  18. [Usefulness of transvaginal Doppler color in ovarian neoplasms diagnosis].

    Science.gov (United States)

    Muñoz, H; Martínez, L; Parra, M; Cunill, E; Polanco, M; Leible, S; Romero, C

    1993-01-01

    The vascular resistant evaluation by Doppler waveform is a method used in clinic and research. The neoplastic malignant has an increased growth with an increased amount of neomalignant vessels. The presence of these vessels produce an increase of the transversal section area from the tumoral vascular system, therefore there is a decrease in the vascular resistance. The main objective of this work is to show the usefulness of Doppler waveform as predictor factor of malignity in ovary tumors. Eighteen patients with tumoral mass in the ovary were studied. They were between 21 and 67 years old (mean = 43). The tumoral volume and the flow resistance of blood vessels which irrigated those tumoral mass were evaluated by transvaginal ultrasound with color and pulsed Doppler. The pulsatility index (SD/media) was used. The Chi cuadrado test was used to evaluate the results. The results show the presence of six malignant tumors, three of them with low malignicity and the presence of twelve benign tumors. The age of the patients between both groups (malignant and benign tumors) were significant different (40.7 versus 52 years old, p < 0.001). The mean tumoral volume was 65 ml, with a range of 17 to 225 ml in the group of patients with benign tumors and the mean tumoral volume from patients with malignant tumors was 951 ml with a range of 141 to 3142 ml. The difference in the tumoral in both groups was significative with p < 0.001.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Digital storage and analysis of color Doppler echocardiograms

    Science.gov (United States)

    Chandra, S.; Thomas, J. D.

    1997-01-01

    Color Doppler flow mapping has played an important role in clinical echocardiography. Most of the clinical work, however, has been primarily qualitative. Although qualitative information is very valuable, there is considerable quantitative information stored within the velocity map that has not been extensively exploited so far. Recently, many researchers have shown interest in using the encoded velocities to address the clinical problems such as quantification of valvular regurgitation, calculation of cardiac output, and characterization of ventricular filling. In this article, we review some basic physics and engineering aspects of color Doppler echocardiography, as well as drawbacks of trying to retrieve velocities from video tape data. Digital storage, which plays a critical role in performing quantitative analysis, is discussed in some detail with special attention to velocity encoding in DICOM 3.0 (medical image storage standard) and the use of digital compression. Lossy compression can considerably reduce file size with minimal loss of information (mostly redundant); this is critical for digital storage because of the enormous amount of data generated (a 10 minute study could require 18 Gigabytes of storage capacity). Lossy JPEG compression and its impact on quantitative analysis has been studied, showing that images compressed at 27:1 using the JPEG algorithm compares favorably with directly digitized video images, the current goldstandard. Some potential applications of these velocities in analyzing the proximal convergence zones, mitral inflow, and some areas of future development are also discussed in the article.

  20. Biometric, B-mode and color Doppler ultrasound assessment of eyes in healthy dogs

    Directory of Open Access Journals (Sweden)

    Elzivânia G. Silva

    Full Text Available ABSTRACT: B-scan ultrasonography is an important diagnostic tool that allows characterization of internal organ anatomy and, when complemented by Doppler ultrasound, allows vascular hemodynamic assessment, increasing the diagnostic accuracy. Thus, the aim of the present study was the B-scan ultrasound characterization and measurement of the eyeball segments and assessment of the external ophthalmic artery by color and pulsed Doppler. Sixty eyeballs were assessed from 30 dogs of different breeds using an 8.5MHz microconvex transductor. First, biometry was performed by B-scan of the following segments: axial length (M1, anterior chamber depth (M2, lens thickness (M3, lens length (M4, vitreous chamber depth (M5, optical disc length (M6 and optic nerve diameter (M7. Colored Doppler identified the external ophthalmic article and pulsed Doppler assessed its flow, and the following were measured: systolic peak velocity (VPS, final diastolic velocity (VDF, resistivity index (IR and pulse index (IP. No statistical difference was observed for the biometric values of the eye segments between the right and left eyes (p>0.05. The vitreous chamber depth (M5 was shown to be the biometric variable with greatest bilateral symmetry, varying from 0.79 to 0.87cm and 0.78 to 0.86cm for the right and left eye, respectively. The ophthalmic artery was visualized over the optic nerve towards the eyeball, with flow stained red. There was no significant statistical difference between the Doppler velocimetric values for the ophthalmic artery between the right and left eye of the animals assessed (p>0.05. The mean resistivity index (RI showed average values equal to 0.63±0.03, bilaterally. The mean base velocity was 17.50cm/s and 18.18cm/s at the systolic peak and 6.21cm/s and 6.68cm/s at the end of the diastole, for the right and left eyes respectively. The anatomic, biometric and hemodynamic characterization using the ultrasound B-scan and the Doppler modalities

  1. Discrimination between pleural thickening and minimal pleural effusion using color Doppler chest ultrasonography

    Directory of Open Access Journals (Sweden)

    Ali A. Hasan

    2013-07-01

    Conclusions: Application of color Doppler examination increases the accuracy of real time chest ultrasound to discriminate pleural thickening from minimal pleural effusion and hence color Doppler examination proved to be a useful diagnostic tool to real-time gray-scale ultrasound for diagnosis of minimal pleural effusion.

  2. Bubble-Induced Color Doppler Feedback for Histotripsy Tissue Fractionation.

    Science.gov (United States)

    Miller, Ryan M; Zhang, Xi; Maxwell, Adam D; Cain, Charles A; Xu, Zhen

    2016-03-01

    Histotripsy therapy produces cavitating bubble clouds to increasingly fractionate and eventually liquefy tissue using high-intensity ultrasound pulses. Following cavitation generated by each pulse, coherent motion of the cavitation residual nuclei can be detected using metrics formed from ultrasound color Doppler acquisitions. In this paper, three experiments were performed to investigate the characteristics of this motion as real-time feedback on histotripsy tissue fractionation. In the first experiment, bubble-induced color Doppler (BCD) and particle image velocimetry (PIV) analysis monitored the residual cavitation nuclei in the treatment region in an agarose tissue phantom treated with two-cycle histotripsy pulses at [Formula: see text] using a 500-kHz transducer. Both BCD and PIV results showed brief chaotic motion of the residual nuclei followed by coherent motion first moving away from the transducer and then rebounding back. Velocity measurements from both PIV and BCD agreed well, showing a monotonic increase in rebound time up to a saturation point for increased therapy dose. In a second experiment, a thin layer of red blood cells (RBC) was added to the phantom to allow quantification of the fractionation of the RBC layer to compare with BCD metrics. A strong linear correlation was observed between the fractionation level and the time to BCD peak rebound velocity over histotripsy treatment. Finally, the correlation between BCD feedback and histotripsy tissue fractionation was validated in ex vivo porcine liver evaluated histologically. BCD metrics showed strong linear correlation with fractionation progression, suggesting that BCD provides useful quantitative real-time feedback on histotripsy treatment progression.

  3. Doppler color flow mapping of peripheral vessels: Comparison of angiodynography with conventional duplex US

    International Nuclear Information System (INIS)

    Merritt, C.R.B.; Bluth, E.I.; Sullivan, M.A.

    1986-01-01

    A new Doppler color flow imager was compared to duplex US in the evaluation of carotid and peripheral vessels in 50 patients. A 7.5-MHz transducer permitted simultaneous high-resolution real-time imaging of Doppler flow and tissue. The system was found to have excellent image quality and Doppler sensitivity. Flow characteristics and velocity measurements obtained with this system correlated well with those obtained using the duplex scanner and were obtained more quickly than with the conventional system, allowing more complete assessment of flow characteristics. Color Doppler flow imaging appears to be an extremely promising method for the rapid and effective evaluation of peripheral vascular flow

  4. Transesophageal color Doppler evaluation of obstructive lesions using the new "Quasar" technology.

    Science.gov (United States)

    Fan, P; Nanda, N C; Gatewood, R P; Cape, E G; Yoganathan, A P

    1995-01-01

    Due to the unavoidable problem of aliasing, color flow signals from high blood flow velocities cannot be measured directly by conventional color Doppler. A new technology termed Quantitative Un-Aliased Speed Algorithm Recognition (Quasar) has been developed to overcome this limitation. Employing this technology, we used transesophageal color Doppler echocardiography to investigate whether the velocities detected by the Quasar would correlate with those obtained by continuous-wave Doppler both in vitro and in vivo. In the in vitro study, a 5.0 MHz transesophageal transducer of a Kontron Sigma 44 color Doppler flow system was used. Fourteen different peak velocities calculated and recorded by color Doppler-guided continuous-wave Doppler were randomly selected. In the clinical study, intraoperative transesophageal echocardiography was performed using the same transducer 18 adults (13 aortic valve stenosis, 2 aortic and 2 mitral stenosis, 2 hypertrophic obstructive cardiomyopathy and 1 mitral valve stenosis). Following each continuous-wave Doppler measurement, the Quasar was activated, and a small Quasar marker was placed in the brightest area of the color flow jet to obtain the maximum mean velocity readout. The maximum mean velocities measured by Quasar closely correlated with maximum peak velocities obtained by color flow guided continuous-wave Doppler in both in vitro (0.53 to 1.65 m/s, r = 0.99) and in vivo studies (1.50 to 6.01 m/s, r = 0.97). We conclude that the new Quasar technology can accurately measure high blood flow velocities during transesophageal color Doppler echocardiography. This technique has the potential of obviating the need for continuous-wave Doppler.

  5. Color Doppler flow mapping of stenotic and regurgitant natural heart valves

    International Nuclear Information System (INIS)

    Nanda, N.C.

    1986-01-01

    Color Doppler echocardiography has found widest application in reliable detection and assessment of severity of both atrio-ventricular and semi-lunar valve incompetence. The authors believe both the sensitivity and specificity of color Doppler for the detection of mitral and aortic regurgitation is very high in patients with adequate acoustic windows. In 82 patients with proven mitral regurgitation studied, the best correlations with angiography were noted when the maximum or average regurgitant jet are obtained by color Doppler from three standard 2-D echo planes (parasternal long and short axis and apical four chamber view) and expressed as a percentage of the left atrial area were considered. The criteria the authors used for assessment of tricuspid and pulmonary valve incompetence are similar to those used for mitral and aortic valve incompetence, but the lack of a good ''gold'' standard has hampered validation. The color Doppler technique also supplements conventional Doppler in the assessment of severity of stenotic lesions by facilitating parallel alignment of the continuous wave Doppler cursor line with the stenotic jet for accurate recording of maximal velocities and pressure gradients. The authors have found this method especially useful in the assessment of aortic stenosis. In conclusion, color Doppler flow mapping combined with conventional echocardiography provides, for the first time, a comprehensive noninvasive assessement of the severity of regurgitant and stenotic lesions

  6. Endosonographic and color doppler flow imaging alterations observed within irradiated rectal cancer

    International Nuclear Information System (INIS)

    Alexander, Archie A.; Palazzo, Juan P.; Ahmad, Neelofur R.; Liu, J.-B.; Forsberg, Flemming; Marks, John

    1996-01-01

    Purpose: To correlate the endosonographic and color Doppler flow imaging alterations observed in irradiated rectal cancers with the pathologic features of radiation response, and to evaluate the potential impact of altered blood flow on the integrity of the surgical anastamosis. Methods and Materials: Endosonography with color and pulsed wave Doppler was performed on 20 rectal cancer masses before and after high dose preoperative radiation (XRT). Pre- and post-XRT observations included comparing alterations in tumor size, sonographic echotexture, color Doppler flow, and pulsatility indices. Comparisons were made with pathologic findings in the irradiated specimens and with the incidence of anastomotic failure. Results: Compared to pre-XRT observations, irradiated rectal cancers decreased in size and became either mixed in echogenicity with less apparent color Doppler flow (16 of 20) or unchanged in color Doppler flow and echotexture (4 of 20). Those with less flow (16 of 20) were imaged later (mean = 90.2 ± 12.1 days) than those without change in color Doppler flow (mean = 21.7 ± 2.7 days). Pathologically, the group of four without change in color Doppler signal had features of acute inflammation which were not observed in 16 of 20 imaged later. Based on pulsatility index measurements, both high and low resistance vessels were detected and confirmed by immunohistochemical staining, and features of postradiation obliterative vasculitis were observed. Only one primary anastomosis in 14 patients with decreased flow failed. Conclusions: The sonographic and color Doppler flow imaging alterations observed within irradiated rectal cancer correlated with changes of postradiation obliterative vasculitis. The apparent diminished local blood flow within high and low resistance vessels post-XRT did not result in an increased incidence of anastomotic failures

  7. Studi Penentuan Kecepatan Aliran Darah dan Frekuensi Terimaan Pasien Atherosclerosis Menggunakan USG Color Doppler

    OpenAIRE

    Mulyani, Emba

    2014-01-01

    Jurnal Fisika Medik Studi Penentuan Kecepatan Aliran Darah dan Frekuensi Terimaan Pasien Atherosclerosis Menggunakan USG Color Doppler Mulyani H211 08 507 Pembimbing Utama Sri Dewi Astuty Ilyas,Ssi, Msi Nip.19750513 199903 2 001 Pembimbing Pertama Dahlang Tahir, Msi, Ph.D Nip.19750907 200003 1 001 ABSTRACT Research about Study of determination blood speed of current and freq uency give patient atherosclero sis uses plane USG Color Doppler had be...

  8. Phylloedes tumor of breast: findings at mammography, sonography and color Doppler imaging

    International Nuclear Information System (INIS)

    Park, Kun Choon; Ahn, Sei Hyun; Kim, Young Hwan; Choi, Hye Yong; Baek, Seung Yon; Yoon, Jeong Hyun

    1994-01-01

    The phylloides tumor of the breast is rare. the purposes of this study were to find the characteristic findings at mammography, sonography, and color Doppler imaging and to evaluate the usefulness of color Doppler study as an additional modality in the diagnosis of phylloides tumor and differentiation between benign and malignant varieties. Eight cases, who were pathologically proven as pylloides tumors, were retrospectively studied. The findings at histologic examination suggested benign in five, malignantin two, and borderline in one. We analyzed the mammograms of all eight patients and sonogram and color Doppler images of four patients. Phylloides tumors were seen as dense masses with lobulated margins in mammograms. On sonography, they showed relatively well-defined masses with in homogenous internal echo pattern and central echogenic areas. They were characterized by the presence of arterial and venous flows in the center and periphery of the lesion on color Doppler imaging and spectral analysis. We conclude that mammographic, sonographic and even color Doppler findings are not predictive of benign or malignant nature of the phylloides tumor. However, mammography and sonography with color Doppler interrogation are helpful in the diagnosis of phylloides tumor

  9. Magnetic angioresonance of the carotid artery: correlation with color Doppler ultrasound

    International Nuclear Information System (INIS)

    Cotilla, J.; Miralles, M.; Cairols, M.C.; Dolz, J.L.; Vilanova, J.C.; Capdevila, A.

    1998-01-01

    To determine the value of magnetic angioresonance (MAR) in grading carotid stenosis, comparing it with color Doppler and intraarterial digital subtraction angiography (IADSA). A comparative study using color Doppler and MAR was carried out in 84 patients with coratid lesions. Fifty-two of the patients underwent angiographic study as well. The comparison of MAR versus arteriography in discriminating stenosis of more than 70%, expressed in terms of sensitivity specificity, overall precision and the kappa concordance index, gave values of 87.2, 90.8, 89.4 and 0.78%, respectively. When MAR was compared with color Doppler, the results were 86.8, 85.9, 86.3 and 0.72%, respectively. The results of the comparison between color Doppler and arteriography were 82.2, 86.2, 84.6 and 0.68%, respectively. The better correlation of MAR, as compares with angiography and color Doppler, with the grade of carotid stenosis indicates the high degree of reliability. The better correlation of MAR, as compares with angiography and color Doppler, with the grade of carotid stenosis indicates the high degree of reliability of this imaging technique. (Author) 29 refs

  10. Clinical study of color Doppler sonography in Graves' disease blood flow changes after thyroid arteries embolization

    International Nuclear Information System (INIS)

    Zhuang Wenquan; Li Weiduo; Yang Jianyong; Chen Wei; Huang Yonghui; Guo Wenbo; Li Jiaping

    2003-01-01

    Objective: To study the color doppler image characteristics of thyroid arteries pre- and post-interventional procedure and to assess the clinical efficacy in Gnaves' disease. Methods: 11 from 31 patients diagnosed as Graves' disease undertaken thyroid arteries embolization, were analyzed. Color Doppler sonography was applied to monitor the pre-and post- procedure thyroid size and diameters of thyroid arteries. Power Doppler was used to detect the Vmax, Vmin, RI and blood flow. Results: After thyroid arteries embolization, the size and vascularity of thyroids were reduced. The thyroid arteries showed shrinkage and stoppage blood flow at the embolized site. The changes of RI, blood parameters of Vmax, Vmin and diameters of the thyroid arteries pre- and post-procedure turned out to be statistically significant for clinical restriction. Conclusion: The color Doppler sonography plays an important role for preoperative diagnosis and predicting the prognosis

  11. The use of contrast-enhanced color doppler ultrasound in the differentiation of retinal detachment from vitreous membrane

    International Nuclear Information System (INIS)

    Han, Sang Suk; Chang, Seung Kook; Yoon, Jung Hee; Lee, Young Joon

    2001-01-01

    To compare the clinical utility of contrast-enhanced color Doppler US in the differentiation of retinal detachment (RD) from vitreous membrane (VM) with that of various conventional US modalities, and to analyze the enhancement patterns in cases showing an enhancement effect. In 32 eyes examined over a recent two-year period, RD (n=14) and VM (n=18) were confirmed by surgery (n=28) or clinical follow-up (n=4). In all cases, gray-scale, color Doppler, and power Doppler US were performed prior to contrast injection, and after the intravenous injection of Levovist (Schering, Berlin) by hand for 30 seconds at a dose of 2.5 g and a concentration of 300 mg/mL via an antecubital vein, contrast-enhanced color Doppler US was performed. At Doppler US, the diagnostic criterion for RD and VM was whether or not color signals were visualized in membranous structures. Diagnostic accuracy was 78% at gray-scale US, 81% at color Doppler US, 59% at power Doppler US, and 97% at contrast-enhanced color Doppler US. The sensitivity of color Doppler US to color signals in RD increased from 57% to 93% after contrast enhancement. The enhancement patterns observed were signal accentuation (n=3), signal extension (n=2), signal addition (n=3), and new signal visualization (n=5). Contrast-enhanced color Doppler US was the most accurate US modality for differentiating RD from VM, showing a significantly increased signal detection rate in RD

  12. Optical Doppler tomography based on a field programmable gate array

    DEFF Research Database (Denmark)

    Larsen, Henning Engelbrecht; Nilsson, Ronnie Thorup; Thrane, Lars

    2008-01-01

    We report the design of and results obtained by using a field programmable gate array (FPGA) to digitally process optical Doppler tomography signals. The processor fits into the analog signal path in an existing optical coherence tomography setup. We demonstrate both Doppler frequency and envelope...... extraction using the Hilbert transform, all in a single FPGA. An FPGA implementation has certain advantages over general purpose digital signal processor (DSP) due to the fact that the processing elements operate in parallel as opposed to the DSP. which is primarily a sequential processor....

  13. Analysis of multiple scattering effects in optical Doppler tomography

    DEFF Research Database (Denmark)

    Yura, H.T.; Thrane, L.; Andersen, Peter E.

    2005-01-01

    Optical Doppler tomography (ODT) combines Doppler velocimetry and optical coherence tomography (OCT) to obtain high-resolution cross-sectional imaging of particle flow velocity in scattering media such as the human retina and skin. Here, we present the results of a theoretical analysis of ODT where...... multiple scattering effects are included. The purpose of this analysis is to determine how multiple scattering affects the estimation of the depth-resolved localized flow velocity. Depth-resolved velocity estimates are obtained directly from the corresponding mean or standard deviation of the observed...

  14. Power and color Doppler ultrasound settings for inflammatory flow: impact on scoring of disease activity in patients with rheumatoid arthritis.

    Science.gov (United States)

    Torp-Pedersen, Søren; Christensen, Robin; Szkudlarek, Marcin; Ellegaard, Karen; D'Agostino, Maria Antonietta; Iagnocco, Annamaria; Naredo, Esperanza; Balint, Peter; Wakefield, Richard J; Torp-Pedersen, Arendse; Terslev, Lene

    2015-02-01

    To determine how settings for power and color Doppler ultrasound sensitivity vary on different high- and intermediate-range ultrasound machines and to evaluate the impact of these changes on Doppler scoring of inflamed joints. Six different types of ultrasound machines were used. On each machine, the factory setting for superficial musculoskeletal scanning was used unchanged for both color and power Doppler modalities. The settings were then adjusted for increased Doppler sensitivity, and these settings were designated study settings. Eleven patients with rheumatoid arthritis (RA) with wrist involvement were scanned on the 6 machines, each with 4 settings, generating 264 Doppler images for scoring and color quantification. Doppler sensitivity was measured with a quantitative assessment of Doppler activity: color fraction. Higher color fraction indicated higher sensitivity. Power Doppler was more sensitive on half of the machines, whereas color Doppler was more sensitive on the other half, using both factory settings and study settings. There was an average increase in Doppler sensitivity, despite modality, of 78% when study settings were applied. Over the 6 machines, 2 Doppler modalities, and 2 settings, the grades for each of 7 of the patients varied between 0 and 3, while the grades for each of the other 4 patients varied between 0 and 2. The effect of using different machines, Doppler modalities, and settings has a considerable influence on the quantification of inflammation by ultrasound in RA patients, and this must be taken into account in multicenter studies. Copyright © 2015 by the American College of Rheumatology.

  15. Ultrasonographic investigation of the Achilles tendon in elite badminton players using color Doppler.

    Science.gov (United States)

    Boesen, Morten Ilum; Boesen, Anders; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren

    2006-12-01

    The most frequent injuries in badminton players are in the lower extremities, especially in the Achilles tendon. The game of badminton may be related to abnormal intratendinous flow in the Achilles tendon as detected by color Doppler ultrasound. To a certain extent, this blood flow might be physiological, especially when examined after match. Cohort study (prevalence); Level of evidence, 3. Seventy-two elite badminton players were interviewed regarding Achilles tendon pain (achillodynia) in the preceding 3 years. Color Doppler was used to examine the tendons of 64 players before their matches and 46 players after their matches. Intratendinous color Doppler flow was graded from 0 to 4. The Achilles tendon was divided into dominant (eg, right side for right-handed players and vice versa) and nondominant side and classified as midtendon, preinsertional, and calcaneal areas. Of 72 players, 26 had experienced achillodynia in 34 tendons, 18 on the dominant side and 16 on the nondominant side. In 62% of the players with achillodynia, the problems had begun slowly, and the median duration of symptoms was 4 months (range, 0-36 months). Thirty-five percent had ongoing pain in their tendons for a median duration of 12 months (range, 0-12 months). Achillodynia was not associated with the self-reported training load or with sex, age, weight, singles or doubles players, or racket side. Forty-six players were scanned before and after match. At baseline, color Doppler flow was present in the majority of players, and only 7 (16%) players had no color Doppler flow in either tendon. After match, all players had some color Doppler flow in 1 or both tendons. Achillodynia and color Doppler flow were related in the nondominant Achilles tendon (chi-square, P = .008). The grades of Doppler flow also increased significantly after match in the preinsertional area in both the nondominant (P = .0002) and dominant (P = .005) side tendons. A large proportion of the players had experienced

  16. Analysis on correlation between overall classification on color doppler ultrasound and clinical stages of atherosclerosis obliterans

    International Nuclear Information System (INIS)

    Zhang Dongmei; Liu Meihan; Shi Weidong; Chen Enqi; Li Xinying; Lin Yu

    2010-01-01

    Objective: To investigate the correlation and the clinical significance between the overall classification on color Doppler ultrasound and the clinical stages of atherosclerosis obliterans (ASO), and evaluate the extent of arterial lesions comprehensively. Methods: 125 patients of ASO, who were divided into three groups of mild, moderate and severe with Color Doppler ultrasound according to differences of occlusion, quantity, degree of stenosis and collateral number, were analyzed with clinical stages, then their associations were studied with Spearman rank analysis. Results: The clinical manifestations of ASO patients who were divided into three groups of mild, moderate and severe according to overall classification on color Doppler ultrasound were respectively gradually serious, which had positive correlations with the stages of I, II and III according to clinical stages. Spearman rank analysis showed that the correlation coefficients (rs)was 0.797 2 between two groups (P<0.01), there was good consistency between the overall classification on color Doppler ultrasound and the clinical stagesof ASO. Conclusion: The overall classification of ASO on color Doppler ultrasound has considered impact of many other factors on the clinical symptoms,such as the level of the local narrow, narrow scope, segments of occlusion and collateral arteries, which divides the lesions more objectively, shows good consistency with the clinical stages. (authors)

  17. Alveolar Echinococcosis of the Liver: Correlative Color Doppler US, CT, and MRI Study

    International Nuclear Information System (INIS)

    Cokun, A.; Oeztuerk, M.; Karahan, O.I.; Erdogan, N.; Ikin, S.; Guelec, M.

    2004-01-01

    Purpose: To determine and compare the imaging features of hepatic alveolar Echinococcosis using color Doppler US, CT, and MRI. Material and Methods: Abdominal CT and MRI with and without contrast agents and color Doppler US were performed on seven patients with hepatic alveolar Echinococcosis. The lesions were evaluated for location, features of echogenicity, intensity and density, calcification, and vascular, hilar, and perihepatic involvement. The diagnosis was confirmed histopathologically in all patients. Results: Six patients had solitary lesions, and one displayed multiple lesions. The lesions were generally seen as heterogeneous and hyper- or hypoechoic when imaged with color Doppler US, hypodense with CT, and hypointense with MRI, in comparison with the liver parenchyma. Calcification, central necrosis, and small peripheral cysts were observed in six, seven, and four patients, respectively. Vascular flow or contrast enhancement was not observed in any of the cases. A look at the respective advantages of each method reveals that calcification was best rendered visible via CT, small peripheral cysts with T2-weighted MRI, central necrosis with CT and MRI, and perihepatic invasion with multiplanar MRI. Vascular involvement was revealed by all methods. Conclusion: Color Doppler US, CT, and MR imaging function extremely well as complementary methods in the diagnosis of HAE. Color Doppler US should be performed in these patients owing to its ability to efficiently detect the disease. Knowledge of imaging characteristics makes it possible to radiologically ascertain an early diagnosis

  18. Ultrasonography and color Doppler in juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2012-01-01

    The wrist region is one of the most complex joints of the human body. It is prone to deformity and functional impairment in juvenile idiopathic arthritis (JIA), and is difficult to examine clinically. The aim of this study was to evaluate the role of ultrasonography (US) with Doppler in diagnosis...

  19. Optical coherence techniques for plasma doppler spectroscopy

    International Nuclear Information System (INIS)

    Howard, J.; Michael, C.; Glass, F.; Cheetham, A.D.

    2000-01-01

    A new electro-optically Modulated Optical Solid-State (MOSS) interferometer has been constructed for measurement of the low order spectral moments of line emission from optically thin radiant media. The instrument, which is based on the principle of the Fourier transform spectrometer, has high etendue and is rugged, compact and inexpensive. By employing electro-optical path-length modulation techniques, the spectral information is transferred to the temporal frequency domain and can be obtained using a single photodetector. Specifically, the zeroth moment (brightness) is given by the average signal level, the first moment (shift) by the modulation phase and the second moment (line width) by the modulation amplitude. (author)

  20. Acute scrotal pathology in Schonlein-Henoch purpura: management by color Doppler ultrasound. A case report

    International Nuclear Information System (INIS)

    Jornet, J.; Cervera, J.; Marco, S.F.; Gonzalez, M.

    1998-01-01

    Schonlein-Henoch purpura is the most common form of purpura in children. It can affect a number of organs, but scrotal involvement is rare. We present a case of scrotal hemorrhage and epidymo-orchitis, diagnosed by color Doppler ultrasound, in which conservative treatment was employed. The differential diagnosis involves testicular torsion, which is also, although less frequently, associated with Schonlein-Henoch purpura. color Doppler ultrasound results in the correct diagnosis, ruling out testicular torsion and avoiding surgical exploration of the testicles. (Author) 8 refs

  1. Color Doppler Ultrasonography-Targeted Perforator Mapping and Angiosome-Based Flap Reconstruction

    DEFF Research Database (Denmark)

    Gunnarsson, Gudjon Leifur; Tei, Troels; Thomsen, Jørn Bo

    2016-01-01

    Knowledge about perforators and angiosomes has inspired new and innovative flap designs for reconstruction of defects throughout the body. The purpose of this article is to share our experience using color Doppler ultrasonography (CDU)-targeted perforator mapping and angiosome-based flap reconstr......Knowledge about perforators and angiosomes has inspired new and innovative flap designs for reconstruction of defects throughout the body. The purpose of this article is to share our experience using color Doppler ultrasonography (CDU)-targeted perforator mapping and angiosome-based flap...

  2. Diagnosis of Cervical Abortion by TransvaginaI Color Doppler Sonography : A Case Report

    International Nuclear Information System (INIS)

    Lee, Eun Ju; Ryu, Hee Sug; Ji, Hoon; Suh, Jung Ho

    1995-01-01

    Cervical abortion is a spontaneous abortion of an intrauterine pregnancy into the cervical canal where the abortus is retained by a closed external os, causing distension of the cervical canal. Cervical abortion should be distinguished from the cervical pregnancy. We present a case of cervical abortion diagnosed preoperatively by transvaginal sonography and color doppler imaging, and treated by dilatation and curettage. Charateristic transvaginal sonographic findings and identification of subtrophoblastic blood flow by color doppler imaging could allow differentiation of the cevical aborition from the cervical pregnancy

  3. The Role of Color Doppler Ultrasonography in Characterization of Thyroid Tumors

    International Nuclear Information System (INIS)

    Kim, Hee Soo; Jeon, Pyong; Won, Jong Yoon; Na, Jae Beom; Lee, Hyang Mee; Yoo, Hyung Sik; Lee, Jong Tae; Park, Jeong Soo; Cho, Nam Hoon

    1995-01-01

    To assess the usefulness of color Doppler ultrasonography in the characterization of thyroid tumors, surgically proven 88 nodules in 85 patients were evaluated. Using 10 MHz linear array transducer, gray scale images were initially evaluated. Then, distribution pattern of color signals (marginal, intra-tumoral, mixed) and graded internal vascularity according to morphology of color signal (0:absence of internal signal, 1: spotty, 2: linear,3: branching) were observed on color doppler imaging. Pulsed doppler waves were analyzed with parameters including peak systolic velocity(PSV), resistive index(RI), and pulsatile index(PI). Significantly larger numbers of intra-tumoral type, 20 cases(62.5%), were observed in malignant nodules, whereas mixed forms were predominant in benign group, 37 cases (66%) In graded internal vascularity, malignant nodules tended to have grade 2 or 3 signals, whereas benign nodules tended to have grade 0 or 1 signals. Spectral wave analysis show no significant difference in the value of PSV, RI, and PI between malignancy and benignity group. In conclusion, color Doppler imaging has a potential role in the characterization of thyroid nodules as a supportive method for gray scale diagnosis

  4. Color Doppler Score: A New Approach for Monitoring a Large Placental Chorioangioma

    Directory of Open Access Journals (Sweden)

    Maria Angelica Zoppi

    2014-01-01

    Full Text Available We employed color Doppler score as an innovative approach for the prenatal diagnosis and monitoring of a large placental chorioangioma case diagnosed at 26 weeks and the subjective semiquantitative assessment of the vascularization. The blood flow was assessed by a color Doppler score based on the intensity of the color signal with the following value ranges: (1 no flow, (2 minimal flow, (3 moderate flow, and (4 high vascular flow. Weekly examinations were programmed. Initially, a color Doppler score 3 was assigned, remaining unchanged at the following two exams and decreasing to Score 2 in the following 2 exams and to Score 1 thereafter. The ultrasonographic scan showed an increase of the mass size at the second and third exams and was followed by an arrest of the growth persisting for the rest of the pregnancy. Some hyperechogenic spots inside the mass appeared at the end. Expectant management was opted for, and the delivery was at 39, 2 weeks and maternal and fetal outcomes were favourable. The color Doppler score employed for assessment of vascularization in successive examinations proved to be an important tool for the prediction of the chorioangioma involution, and this new approach of monitoring allowed effective surveillance and successful tailored management.

  5. Multipoint photonic doppler velocimetry using optical lens elements

    Science.gov (United States)

    Frogget, Brent Copely; Romero, Vincent Todd

    2014-04-29

    A probe including a fisheye lens is disclosed to measure the velocity distribution of a moving surface along many lines of sight. Laser light, directed to the surface and then reflected back from the surface, is Doppler shifted by the moving surface, collected into fisheye lens, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to an index-matching lens and eventually to a fisheye lens. The fiber array flat polished and coupled to the index-matching lens using index-matching gel. Numerous fibers in a fiber array project numerous rays through the fisheye lens which in turn project many measurement points at numerous different locations to establish surface coverage over a hemispherical shape with very little crosstalk.

  6. Vesico-ureteral reflux: diagnosis and staging with voiding color doppler US Preliminary experience

    International Nuclear Information System (INIS)

    Farina, Renato; Arena, Carmela; Pennisi, Francesco; Di Benedetto, Vincenzo; Politi, Guido; Di Benedetto, Aurelio

    2000-01-01

    Introduction: The aim of this study is to assess the accuracy of a new US examination: 'voiding color Doppler US ' in the early diagnosis and staging of vesico-ureteral reflux (VUR). The contrast agent US was SH U 508A (Levovist, Schering, Berlin), which produces a chromatic accentuation of the signals picked up by the color Doppler US. Eighteen patients (10 females, eight males) were recruited for the study. In two patients a second examination was performed for follow-up after a VUR conservative therapy. All patients were taken under examination for the evaluation of possible VUR. In all patients the voiding color Doppler US was followed by voiding cystourethrography (VCUG) and the data obtained were compared. Materials and methods: A total of 18 patients aged between 3 months and 10 years, were recruited for the study. The results of the examination were the following: urinary tract infections, follow-up of VUR after conservative or surgical therapy, miscellaneous indications. Voiding color Doppler US was performed, followed by a VCUG. The voiding color Doppler US consists in the trans-catheter introduction of a contrast agent SHU 508 A (Levovist, Schering, Ag. Berlin) into the bladder and a subsequent test with the color Doppler US to show or exclude the presence of reflux into the ureters and/or into the pyelo-caliceal cavity of the kidneys. After the introduction of the contrast agent US the ultrasound scanning of the bladder, the ureters and the pyelo-caliceal cavity was performed to examine the reflux degree. The ultrasonographic investigations were perfomed with AU 590 asyncronus US (Esaote Biomedica, Genova) with a 3.5 MHz convex probe. Results: After the trans-catheter introduction of the contrast agent US, vesico-ureteral reflux occured in 13 patients (77.2%). The reflux degree was also measured by means of ultrasound and was later confirmed by VCUG. The mean times of each examination were as follows: initial US, 10 min; catheterization, 8 min; voiding

  7. Vascular response to ischemia in the feet of falanga torture victims and normal controls--color and spectral Doppler findings

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Amris, Kirstine; Holm, Christian Cato

    2009-01-01

    to controls. On color Doppler this would be seen as less color after ischemia and on spectral Doppler as elevated resistive index (RI). METHODS: Ten male torture victims from the Middle East and nine age, sex and ethnically matched controls underwent Doppler examination of the abductor hallucis and flexor...... digitorum brevis muscles before and after two minutes ischemia induced with a pressure cuff over the malleoli. The color Doppler findings were quantified with the color fraction (CF) before and after ischemia. On spectral Doppler the resistive index was measured once before and three consecutive times after....... However, the trend in RI still supports the hypothesis. The negative findings may be due to inadequate design where the CF and RI were measured in one setting, perhaps resulting in both methods being applied imperfectly. The response to ischemia seems short-lived and we suggest that the Doppler methods...

  8. Spectroscopic Doppler analysis for visible-light optical coherence tomography

    Science.gov (United States)

    Shu, Xiao; Liu, Wenzhong; Duan, Lian; Zhang, Hao F.

    2017-12-01

    Retinal oxygen metabolic rate can be effectively measured by visible-light optical coherence tomography (vis-OCT), which simultaneously quantifies oxygen saturation and blood flow rate in retinal vessels through spectroscopic analysis and Doppler measurement, respectively. Doppler OCT relates phase variation between sequential A-lines to the axial flow velocity of the scattering medium. The detectable phase shift is between -π and π due to its periodicity, which limits the maximum measurable unambiguous velocity without phase unwrapping. Using shorter wavelengths, vis-OCT is more vulnerable to phase ambiguity since flow induced phase variation is linearly related to the center wavenumber of the probing light. We eliminated the need for phase unwrapping using spectroscopic Doppler analysis. We split the whole vis-OCT spectrum into a series of narrow subbands and reconstructed vis-OCT images to extract corresponding Doppler phase shifts in all the subbands. Then, we quantified flow velocity by analyzing subband-dependent phase shift using linear regression. In the phantom experiment, we showed that spectroscopic Doppler analysis extended the measurable absolute phase shift range without conducting phase unwrapping. We also tested this method to quantify retinal blood flow in rodents in vivo.

  9. Evaluation of diagnosis of small breast cancer with high frequency and color doppler ultrasound

    International Nuclear Information System (INIS)

    Xia Guobing; Hu Chunhong; Jing Qiulong

    2008-01-01

    Objective: To probe the features of high frequency ultrasonography (HFU) and color Doppler ultrasound (CDU) in the case of small breast cancers in order to evaluate the diagnostic value for small breast cancer with CDU. Methods: The features of HFU and CDU were respective analyzed in 67 small breast masses, the biggest diameter of which was under 2cm identified with pathology. Results Partially characteristic changes of small breast cancers were displayed, and micro-calcification within the mass was an important characteristic, in addition, the Resistant Index (RI) ≥ 0.70 on Pulsed Doppler (PD) and the grade of blood flow on Color Doppler Flow Imaging (CDFI)≥T2 implied much more positive malignancy prediction. Conclusion: HFU integrated with CDU can be used for the early and accurate diagnosis of the small breast cancer. (authors)

  10. Color doppler findings of gastric varices compared with findings on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Takahiro; Yamazaki, Katsu; Toyota, Jouji; Karino, Yoshiyasu; Ohmura, Takumi; Suga, Toshihiro [Sapporo Kosei General Hospital (Japan)

    2002-08-01

    The aim of this study was to evaluate the hemodynamics of gastric varices. We evaluated the detection rates of gastric varices, inflowing vessels to gastric varices, and outflowing vessels from gastric varices in 24 patients with gastric varices, using color Doppler sonography, and compared these findings with computed tomography findings. Eighteen patients had F2-type varices and 6 had F3-type, classified according to the Japanese Research Society for Portal Hypertension. Fourteen patients had fundal varices, and 10 had cardiac and fundal varices. The detection rates of collateral veins using color Doppler sonography were as follows: gastric varices were detected in all 24 patients (100%); inflowing vessels, in 21 of the 24 patients (87.5%); and outflowing vessels, in 18 of the 24 patients (75.0%). The detection rates of collateral veins, using computed tomography, were: gastric varices were detected in all 24 patients (100%); inflowing vessels, in all 24 patients (100%); and outflowing vessles, in 21 of the 24 patients (87.5%). The color Doppler findings agreed perfectly with the computed tomography findings in 13 of the 24 patients (54.2%). Although color Doppler sonography is a useful, noninvasive modality for evaluating the hemodynamics of gastric varices, it falls short in visualizing the detailed hemodynamics of the inflowing and outflowing vessels of gastric varices in half of the patients when compared with computed tomography. (author)

  11. The color Doppler ultrasonography in in the diagnosis of deep vein thrombosis

    International Nuclear Information System (INIS)

    Ameneiro Perez, Santiago; Alvarez Sanchez, Jose A.; Rodriguez Villalonga, Luis; Borras Migues, Marisela; Quinnones Castro, Mayda

    2004-01-01

    The paper was aimed at evaluating the accuracy of color Doppler ultrasonography, a noninvasive method, in the diagnosis of deep vein thrombosis of the lower limbs, comparing it to the results of the cruel and costly diagnostic g olden rule , that is, phlebography. Methods: Color Doppler ultrasonography served to assess 102 patients clinically suspected of deep vein thrombosis of the lower limbs, taking into account the following criteria: vein compressibility, echographic images, color, Vein Doppler signal modulation after several maneuvers and distal compression. Sensitivity, specificity, positive and negative predictive values and diagnostic efficacy were estimated for each criteria, taking the phlebography as a reference. Results: Total or partial lack of vein compressibility combined with the vein flow evaluation is the ultrasonographic criterion that reveals higher degree of sensitivity, specificity and efficacy (0,98; 0,95 and 0,97 respectively. Color Doppler ultrasonography is a highly effective noninvasive diagnostic method that detects deep vein thrombosis in proximal areas of the lower limbs

  12. Assessment of ureterovesical jet dynamics in obstructed ureter by urinary stone with color Doppler and duplex Doppler examinations.

    Science.gov (United States)

    Jandaghi, Ali Babaei; Falahatkar, Siavash; Alizadeh, Ahmad; Kanafi, Alireza Rajabzadeh; Pourghorban, Ramin; Shekarchi, Babak; Zirak, Amin Keshavarz; Esmaeili, Samaneh

    2013-04-01

    This study was designed to evaluate ureterovesical jet dynamics in obstructed ureter and to compare it with those of contralateral unobstructed side. Forty-six patients with diagnosis of ureteral stone, based on imaging findings in computed tomography were enrolled in this study. The gray-scale ultrasound exam from both kidneys and urinary bladder was performed. Then, ureterovesical jet characteristics including ureteral jet frequency, duration and peak velocity were assessed by color Doppler and duplex Doppler studies in both obstructed and unobstructed ureters by a radiologist, 15-30 min after oral hydration with 750-1,000 mL of water. When compared with contralateral normal side, the ureterovesical jet in obstructed ureter showed less frequency (0.59 vs. 3.04 jets/min; P < 0.05), shorter duration (1.24 vs. 5.26 s; P < 0.05) and lower peak velocity (5.41 vs. 32.09 cm/s; P < 0.05). The cut-off points of 1.5 jets/min, 2.5 s and 19.5 cm/s for difference of ureteral jet frequency, duration and peak velocity between obstructed and contralateral normal ureters yielded sensitivities of 97.8, 95.6 and 100 % and specificities of 87, 87.9 and 97.8 %, respectively for diagnosis of ureteral obstruction. Given the safety of Doppler study and significant differences in flow dynamics of obstructed versus unobstructed ureters, our findings demonstrated the utility of Doppler ultrasound examination as a useful adjunct to gray-scale ultrasound by improving the accuracy of ultrasound exam in diagnosis of ureteral obstruction.

  13. Usefulness of color and pulsed Doppler's in the evaluation of surgical portosystemic shunts in pediatric patients

    International Nuclear Information System (INIS)

    Berrocal, T.; Prieto, C.; Cortes, P.; Rodriguez, R.; Pastor, I.

    2003-01-01

    Portosystemic shunts are performed to relieve symptomatic portal hypertension symptomatic or removal pressure in hepatic vascularisation in patients with Budd-Chiari's syndrome. Most surgical portosystemic shunts can be suitably studied by means of ultrasound scan complemented by color and pulsed Dopplers, proved one understands the hemodynamics of the surgical procedures involved. This article demonstrates the usefulness and limitations of the ultrasound scan Duplex Doppler in the evaluation of portosystemic shunts performed on pediatric patients. Pulsed Doppler provides information regarding the nature and direction of blood flow. Color doppler is capable of directly revealing the shunt and, in most cases, permits the anastomosis to be located. The types of shunts that appear include proximal and distal spleno-renal, portocaval and mesocaval. Types of vascular connections are illustrated,s well as expected post-surgical blood flow direction in affected vessels. The ultrasound scanning technique is discussed, as well as the criteria for determining vascular permeability. Also highlighted are the advantages, limitations and diagnostic difficulties associated with the different forms of Doppler. (Author) 17 refs

  14. Two-dimensional intraventricular flow mapping by digital processing conventional color-Doppler echocardiography images.

    Science.gov (United States)

    Garcia, Damien; Del Alamo, Juan C; Tanne, David; Yotti, Raquel; Cortina, Cristina; Bertrand, Eric; Antoranz, José Carlos; Perez-David, Esther; Rieu, Régis; Fernandez-Aviles, Francisco; Bermejo, Javier

    2010-10-01

    Doppler echocardiography remains the most extended clinical modality for the evaluation of left ventricular (LV) function. Current Doppler ultrasound methods, however, are limited to the representation of a single flow velocity component. We thus developed a novel technique to construct 2D time-resolved (2D+t) LV velocity fields from conventional transthoracic clinical acquisitions. Combining color-Doppler velocities with LV wall positions, the cross-beam blood velocities were calculated using the continuity equation under a planar flow assumption. To validate the algorithm, 2D Doppler flow mapping and laser particle image velocimetry (PIV) measurements were carried out in an atrio-ventricular duplicator. Phase-contrast magnetic resonance (MR) acquisitions were used to measure in vivo the error due to the 2D flow assumption and to potential scan-plane misalignment. Finally, the applicability of the Doppler technique was tested in the clinical setting. In vitro experiments demonstrated that the new method yields an accurate quantitative description of the main vortex that forms during the cardiac cycle (mean error for vortex radius, position and circulation). MR image analysis evidenced that the error due to the planar flow assumption is close to 15% and does not preclude the characterization of major vortex properties neither in the normal nor in the dilated LV. These results are yet to be confirmed by a head-to-head clinical validation study. Clinical Doppler studies showed that the method is readily applicable and that a single large anterograde vortex develops in the healthy ventricle while supplementary retrograde swirling structures may appear in the diseased heart. The proposed echocardiographic method based on the continuity equation is fast, clinically-compliant and does not require complex training. This technique will potentially enable investigators to study of additional quantitative aspects of intraventricular flow dynamics in the clinical setting by

  15. TORSION TESTIS : ROLE OF COLOR DOPPLER : A STUDY OF 50 CASES

    Directory of Open Access Journals (Sweden)

    Anand

    2015-09-01

    Full Text Available BACKGROUND: T orsion testis is one of the catast r ophic conditions in children and young a d u lts. Traditionally the diagnosis was made clinical presentation and suspicion. Critical decision making is essential to save the testis . OBJECTIVE: To study the usefu lness and efficacy of Doppler ultrasound in correctly diagnosing acute scrotal conditions in children and young adults to save the testis and to avoid negative explorations. METHODS: Over a period of two years 50 patients with acute scrotum were admitted i n general surgery department who underwent Doppler ultrasound scrotum and its efficacy in correctly diagnosing the pathology was analysed. RESULTS: 50 patients with age group <25 years were included in study. Scrotal pain was the most frequent presenting s ymptom of acute scrotum (98% followed by Swelling of the hemiscrolum on the involved side present in 86% of the patients. Doppler ultrasound showed torsion of testis in 18 patients. On Scrotal exploration, torsion of spermatic cord was confirmed in 16 pat ients, one patient had torsion of appendix of testis and the other had Epididymo - orchitis. Thus the sensitivity and specificity of Doppler ultrasonography for testicular torsion was 86.9% and 92.6% respectively. 2 patients with equivocal Doppler findings, but strong clinical suspicion of testicular torsion were explored, and testis was found to be torsed in both two patients. Doppler ultrasonography showed Epididymo - orchitis in 22 patients, torsion of testicular appendage in 2 patients, Idiopathic scrotal edema in one, and in 5 pts no significant pathology found. All twenty patients of epididymo - orchitis, two patients of torsion of testicular appendage, and one patient of idiopathic scrotal edema were managed conservatively. At three weeks follow up, all th e patients were free of symptoms. The sensitivity and specificity of Doppler ultrasonography for epididymo - orchitis was 95% and 100% respectively. CONCLUSIONS: color

  16. Pulsed and Color Doppler Sonographic Findings of Penile Mondor' Disease

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hye Yeon; Chung, Dong Jin; Kim, Kum Won; Hwang, Cheol Mog [University of Konyang School of Medicine, Daejeon (Korea, Republic of)

    2008-04-15

    Penile Mondor's disease is a rare disease that's characterized by thrombosis in the dorsal vein of the penis. Doppler ultrasonography (US) clearly visualizes dorsal vein thrombosis and the associated hemodynamic alterations. Previous studies have demonstrated the typical color Doppler US findings of superficial dorsal vein thrombosis without the flow signals in this area, yet this is insufficient to understand the hemodynamics in penile Mondor's disease. We report here for the first time a cavernosal artery flow signal pattern in a penile Mondor's disease patient, in addition to its previously reported classic US findings. In conclusion, the Doppler US findings of thrombus without blood flow in the superficial dorsal vein and the low-flow, high resistance in the cavernosal artery may be suggestive of penile Mondor's disease.

  17. Ophthalmic artery color Doppler ultrasonography in mild-to-moderate preeclampsia

    Energy Technology Data Exchange (ETDEWEB)

    Ayaz, Tunahan; Akansel, Gur. E-mail: gakansel@superonline.com; Hayirlioglu, Alper; Arslan, Arzu; Suer, Necdet; Kuru, Ihsan

    2003-06-01

    Objective: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. Methods: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. Results: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. Conclusion: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia.

  18. Ophthalmic artery color Doppler ultrasonography in mild-to-moderate preeclampsia

    International Nuclear Information System (INIS)

    Ayaz, Tunahan; Akansel, Gur.; Hayirlioglu, Alper; Arslan, Arzu; Suer, Necdet; Kuru, Ihsan

    2003-01-01

    Objective: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. Methods: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. Results: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. Conclusion: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia

  19. Contrast-enhanced color Doppler ultrasound characteristics in hypervascular breast tumors: comparison with MRI

    International Nuclear Information System (INIS)

    Alamo, L.; Fischer, U.

    2001-01-01

    The aim of this study was to evaluate the accuracy of contrast-enhanced color Doppler ultrasound (CE-US) in comparison with contrast-enhanced MR imaging (CE-MRI) in the discrimination of hypervascularized breast tumors. An additional CE-US of the breast was preoperatively performed in 40 patients with a hypervascular breast lesion detected on CE-MRI. The presence of blood flow signals and the morphological characteristics of the vessels in the breast lesions were evaluated pre- and post-contrast administration, as well as the dynamic aspects of the Doppler signal, including time interval to maximum signal enhancement and persistence of the signal enhancement. Twenty-three carcinomas and 17 fibroadenomas were explored. Considering initial signal enhancement > 100 % after the administration of contrast material as a criterion suggesting malignancy, CE-MRI showed a sensitivity of 100 % and a specificity of 76.5 % in the detection of malignant breast tumors. Color Doppler signals were consistently demonstrated in all carcinomas and in 68.7 % of fibroadenomas after the administration of Levovist, with CE-US showing a sensitivity of 95.6 % and a specificity of 5.9 %. Neither the mean number of vessels per tumor, nor the location of vessels, the time to maximum increase of the Doppler signal or the persistence of signal enhancement showed significant differences between benign and malignant lesions. Additional CE-US does not increase the low specificity of MRI in patients with hypervascularized breast tumors. (orig.)

  20. Color doppler flow imaging in evaluation of uterine arterial embolization of leiomyoma with KMG

    International Nuclear Information System (INIS)

    Li Furong; Guo Yunhuai; Liu Lifang; Liu Jianhua; Guo Yunhuai

    2006-01-01

    Objective: To explore the effectiveness of a new kind of embolization agent-sodium alginate(KMG), and to evaluate the clinical value of 2D color Doppler ultrasound in assessing the therapeutic effect of uterine arterial embolization (UAE) in leiomyomas. Methods: Forty nine patients with symptomatic leiomyomas were undertaken UAE with KMG for the treatment. Sonography was performed at 3-7 days before and, 1, 3, 6 months after UAE with 2D color Doppler for evaluating the 2D echograms and hemodynamics. Results: Forty nine leiomyomas were studied after UAE, showing a marked reduction in the size (35%-90%). No blood flow was demonstrated in the leiomyomas either 3-7 days or 1 month or 3 months after the procedure. The reappearance of blood flow could be seen in only one case. Conclusion: KMG is an efficient embolization agent for the treatment of symptomatic leiomyomas with UAE, and ultrasonography is a useful tool to assess the effectiveness. (authors)

  1. The Efficacy of Magnetic Resonance Imaging and Color Doppler Ultrasonography in Diagnosis of Salivary Gland Tumors

    Directory of Open Access Journals (Sweden)

    Behrooz Davachi

    2014-12-01

    Full Text Available Background and aims. Although salivary gland tumors are not very common, early diagnosis and treatment is crucial because of their proximity to vital organs, and therefore, determining the efficacy of new imaging procedures becomes important. This study aimed to evaluate the efficacy of magnetic resonance imaging (MRI and color doppler ultrasonography parameters in the diagnosis and differentiation of benign and malignant salivary gland tumors. Materials and methods. In this cross-sectional study, color doppler ultrasonography and MRI were performed for 22 patients with salivary gland tumor. Demographic data as well as MRI, color doppler ultrasonography, and surgical parameters including tumor site, signal in MRI images, ultrasound echo, tumor border, lymphadenopathy, invasion, perfusion, vascular resistance index (RI, vascular pulse index (PI were analyzed using Chi-square test, Fisher’s exact test, and independent ttest. Results. The mean age of patients was 46.59±13.97 years (8 males and 14 females. Patients with malignant tumors were older (P < 0.01. The most common tumors were pleomorphic adenoma (36.4%, metastasis (36.4%, and mucoepidermoid carcinoma (9%. Nine tumors (40.9% were benign and 13 (59.1% were malignant. The overall accuracy of MRI and color doppler ultrasonography in determining tumor site was 100% and 95%, respectively. No significant difference observed between RI and PI and the diagnosis of tumor. Conclusion. Both MRI and ultrasonography have high accuracy in the localization of tumors. Well-identified border was a sign of benign tumors. Also, invasion to adjacent structures was a predictive factor for malignancy.

  2. Role of color Doppler in differentiation of Graves' disease and thyroiditis in thyrotoxicosis

    Science.gov (United States)

    Donkol, Ragab Hani; Nada, Aml Mohamed; Boughattas, Sami

    2013-01-01

    AIM: To evaluate the role of thyroid blood flow assessment by color-flow Doppler ultrasonography in the differential diagnosis of thyrotoxicosis and compare it to technetium pertechnetate thyroid scanning. METHODS: Twenty-six patients with thyrotoxicosis were included in the study. Clinical history was taken and physical examination and thyroid function tests were performed for all patients. Thyroid autoantibodies were measured. The thyroid glands of all patients were evaluated by gray scale ultrasonography for size, shape and echotexture. Color-flow Doppler ultrasonography of the thyroid tissue was performed and spectral flow analysis of both inferior thyroid arteries was assessed. Technetium99 pertechnetate scanning of the thyroid gland was done for all patients. According to thyroid scintigraphy, the patients were divided into two groups: 18 cases with Graves’ disease and 8 cases with Hashimoto’s thyroiditis. All patients had suppressed thyrotropin. The diagnosis of Graves’ disease and Hashimoto’s thyroiditis was supported by the clinical picture and follow up of patients. RESULTS: Peak systolic velocities of the inferior thyroid arteries were significantly higher in patients with Graves’ disease than in patients with thyroiditis (P = 0.004 in the right inferior thyroid artery and P = 0.001 in left inferior thyroid artery). Color-flow Doppler ultrasonography parameters demonstrated a sensitivity of 88.9% and a specificity of 87.5% in the differential diagnosis of thyrotoxicosis. CONCLUSION: Color Doppler flow of the inferior thyroid artery can be used in the differential diagnosis of thyrotoxicosis, especially when there is a contraindication of thyroid scintigraphy by radioactive material in some patients. PMID:23671754

  3. Discrimination between pleural thickening and minimal pleural effusion using color Doppler chest ultrasonography

    OpenAIRE

    Hasan, Ali A.; Makhlouf, Hoda A.; Mohamed, Alaa R.M.

    2013-01-01

    Background: The discrimination of pleural thickening from minimal pleural effusion may be difficult as both lesions appear as anechoic on grayscale ultrasound, hence, free of “echoes” does not confirm the presence of pleural fluid. Aim of this study: To evaluate the value of color Doppler ultrasound in differentiating minimal pleural effusion that could be aspirated from pleural thickening and to compare it with grayscale ultrasound. Patients and methods: This analytic cross-sectional s...

  4. A feasability study of color flow doppler vectorization for automated blood flow monitoring.

    Science.gov (United States)

    Schorer, R; Badoual, A; Bastide, B; Vandebrouck, A; Licker, M; Sage, D

    2017-12-01

    An ongoing issue in vascular medicine is the measure of the blood flow. Catheterization remains the gold standard measurement method, although non-invasive techniques are an area of intense research. We hereby present a computational method for real-time measurement of the blood flow from color flow Doppler data, with a focus on simplicity and monitoring instead of diagnostics. We then analyze the performance of a proof-of-principle software implementation. We imagined a geometrical model geared towards blood flow computation from a color flow Doppler signal, and we developed a software implementation requiring only a standard diagnostic ultrasound device. Detection performance was evaluated by computing flow and its determinants (flow speed, vessel area, and ultrasound beam angle of incidence) on purposely designed synthetic and phantom-based arterial flow simulations. Flow was appropriately detected in all cases. Errors on synthetic images ranged from nonexistent to substantial depending on experimental conditions. Mean errors on measurements from our phantom flow simulation ranged from 1.2 to 40.2% for angle estimation, and from 3.2 to 25.3% for real-time flow estimation. This study is a proof of concept showing that accurate measurement can be done from automated color flow Doppler signal extraction, providing the industry the opportunity for further optimization using raw ultrasound data.

  5. Diagnostic agreement between panoramic radiographs and color doppler images of carotid atheroma

    Directory of Open Access Journals (Sweden)

    Claudia Maria Romano-Sousa

    2009-02-01

    Full Text Available The aim of this study was to investigate the agreement between diagnoses of calcified atheroma seen on panoramic radiographs and color Doppler images. Our interest stems from the fact that panoramic images can show the presence of atheroma regardless of the level of obstruction detected by color Doppler images. Panoramic and color Doppler images of 16 patients obtained from the archives of the Health Department of the city of Valença, RJ, Brazil, were analyzed in this study. Both sides of each patient were observed on the images, with a total of 32 analyzed cervical regions. The level of agreement between diagnoses was analyzed using the Kappa statistics. There was a high level of agreement, with a Kappa value of 0.78. In conclusion, panoramic radiographs can help detecting calcifications in the cervical region of patients susceptible to vascular diseases predisposing to myocardial infarction and cerebrovascular accidents. If properly trained and informed, dentists can refer their patients to a physician for a cardiovascular evaluation in order to receive proper and timely medical treatment.

  6. High resolution compression elastography and color doppler sonography in characterization of breast fibroadenoma.

    Science.gov (United States)

    Rjosk-Dendorfer, D; Reu, S; Deak, Z; Hetterich, H; Kolben, T; Reiser, M; Clevert, D A

    2014-01-01

    To evaluate the use of color Doppler sonography and free hand sonoelastography in the assessment of breast fibroadenomas according to their size and shape. From December 2012 to March 2013 women with 16 solid breast masses, classified as BI-RADS category 3 or 4 were examined with B-mode ultrasound, sonoelastography and color Doppler sonography. Lesions were subdivided according to their shape in round, ovoid or macrolobulated and according to their size (fibroadenomas in B-mode sonography could be shown (p = 0.91) and also comparison of Tsukuba-scores and size of masses revealed no significant differences (p = 1.0). Sizes of fibroadenomas ≥2 cm were significantly associated with an increased vascularization of the lesions (p = 0.04) and a macrolobulated appearance in B-mode sonography (p = 0.04). The combination of color Doppler sonography and sonoelastography in addition to B-mode sonography leads to an increased accuracy in distinguishing benign from malignant breast masses and to an improvement in characterization of fibroadenomas independent of their shape or size.

  7. Color/power Doppler transrectal US in prostate cancer: Correlation with Gleason score

    International Nuclear Information System (INIS)

    Kim, Hyo Cheol; Kim, Seung Hyup; Moon, Min Hoan; Park, Byung Kwan; Kim, Keon Ha; Choi, Hyuck Jae; Yoon, Chang Jin

    2002-01-01

    To evaluate the relationship between hypervascularity on color/power Doppler transrectal ultrasonography and the Gleason score of corresponding biopsied specimen in patients with prostatic cancer. From July 1998 to March 2002, one hundred fifty seven patients with pathologically proven prostate cancer at this institution were included, and all of them underwent transrectal ultrasonographic examination. Initially, ultrasonographic findings and pathologic data of 129 patients were retrospectively reviewed and excluded 28 patients whose sonographic images were either unavailable or inconclusive. The presence of hypoechoic lesion on transrectal sonography and hypervascularity on color/power Doppler sonography in the peripheral zone of the prostate was first evaluated, and these sonographic findings and Gleason score of the corresponding biopsied specimen were then compared. Statistical analysis was done by Student t-test using SPSS package. Among one hundred twenty nine patients, ninety four patients had a hypoechoic lesion on gray scale sonography while sixty one showed a hypervascular lesion on color/power Doppler sonography. Fifty seven of 61 patients (93.4%) had hypoechoic lesion on gray scale sonography. The mean Gleason score of patients with hypervascular lesion was 7.9 ± 0.98 whereas that of the patients without hypervascular lesion, 6.9 ± 1.22, showing a statistically significant difference (p<0.01). Prostate cancer with hypervascularity on transrectal sonography appears to have a higher Gleason score on pathologic examination than that without hypervascularity.

  8. Spectral color Doppler in the diagnosis and follow-up of Graves' disease

    International Nuclear Information System (INIS)

    Sponza, Massimo; Bertolotto, Michele; Ricci, Claudio; Fabris, Bruno; Armini, Lorenzo

    1997-01-01

    Hyperthyroidism in Graves' disease is caused by the presence of circulating autoantibodies to the THS receptors on the thyroid cells. Thyroid-suppression therapy prevents hormone production directly, without affecting the pathogenetic process. They performed color Doppler US of the thyroid gland and pulsed Doppler analysis of thyroid artery flow in 21 patients with Graves' disease before and during medical treatment. US results were compared with those of a control group of 40 healthy subjects and correlated with the values of thyroid hormones, TSH and thyroid microsomal and thyroglobulin antibodies. The thyroid gland was hypo vascularized in the control group. Pulsed Doppler examination of the thyroid arteries exhibited peak systolic velocity of PSV 20 ± 4 cm/s, diastolic velocity of 8 ± 1 cm/s, and resistive index of 0.60 ± 0.04. The thyroid gland of Graves' disease patients was hyper vascularized. Pulsed Doppler examination of the thyroid arteries exhibited peak systolic velocity (PSV = 51 ± 12 cm/s), end diastolic velocity (VD = 15 ± 4 cm/s) and resistive index (RI = 0.71 ± 0.04) significantly higher than in normal subjects (p < 0.001). Circulating thyroid hormones and flow parameters normalized after 6-8 months of medical therapy (PSV = 20 ± 6 cm/s, VD = 9 ± 3 cm(s, RI = 0.58 ± 0.07). The color Doppler patterns normalized only in a patient with normal TSH and antibodies. Sampling of the thyroid arteries proved more repeatable than sampling of parenchymal vessels

  9. Cow's milk allergy: color Doppler ultrasound findings in infants with hematochezia.

    Science.gov (United States)

    Epifanio, Matias; Spolidoro, Jose Vicente; Missima, Nathalia Guarienti; Soder, Ricardo Bernardi; Garcia, Pedro Celiny Ramos; Baldisserotto, Matteo

    2013-01-01

    ultrasound (US) has been an important diagnostic tool to identify several causes of gastrointestinal bleeding. Infants with cow's milk allergy (CMA) may present hematochezia and the confirmation of the diagnosis can be difficult. The aim of this study is to describe grayscale and color Doppler ultrasound findings in patients with CMA. we retrospectively studied 13 infants with CMA. All infants presented severe hematochezia and abdominal pain. All underwent an US study with the diagnosis of allergic colitis. This diagnosis was based on clinical findings, recovery after infant or mother exclusion diets in the case of exclusive breastfeeding and positive oral challenge test. the mean age ranged from 1 to 6 months (mean=3.53). Seven out of 13 infants (53.8%) had grayscale and color Doppler sonographic repeated after exclusion diet. Twelve out of 13 (92,3%) showed abnormalities at US and CDUS at beginning. The positive findings suggesting colitis were thickened bowel walls and increased vascularity, especially in the descending and sigmoid colon. Colonoscopy and histopathological findings were compatible with allergic colitis. After a diet change the 13 infants recovered and their oral challenge tests were positive. Doppler US may be very useful in diagnosing secondary colitis, such as CMA, and to exclude several other abdominal diseases that can emulate this disease. Copyright © 2013 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  10. Optical escape factors for Doppler profiles in spherical, cylindrical and plane parallel geometries

    International Nuclear Information System (INIS)

    Otsuka, Masamoto.

    1977-12-01

    Optical escape factors for Doppler profiles in spherical, cylindrical and plane parallel geometries are tabulated over the range of optical depths from 10 -3 to 10 5 . Relations with the known formulae are discussed also. (auth.)

  11. Preload dependence of color M-mode Doppler flow propagation velocity in controls and in patients with left ventricular dysfunction

    DEFF Research Database (Denmark)

    Møller, J E; Poulsen, S H; Søndergaard, E

    2000-01-01

    The purpose of this study was to assess the effects of preload alterations on color M-mode flow propagation velocity (Vp) in volunteers with normal left ventricular (LV) function and in patients with depressed LV function. Color M-mode Doppler echocardiography was performed during Valsalva maneuv...

  12. Contrast-enhanced color Doppler US in breast cancer: Tumoral vascularity correlated with angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun A; Yoon, Kwon Ha; Yun, Ki Jung; Lee, Kwang Man; Park, Ki Han; Juhng, Seon Kwan; Won, Jong Jin [Wonkwang University School of Medicine, Seoul (Korea, Republic of)

    2000-12-15

    To evaluate the effects of contrast-enhanced color Doppler ultrasonography (CDUS) on the depiction of vascularity and flow pattern in breast cancer and to determine the relationship between tumoral vascularity and angiogenesis. Twenty-one patients with breast cancer were prospectively evaluated with CDUS before and after injection of the contrast agent (SH U 508A, 2.5g, 300 mg/ml ). The tumoral vascularity was expressed as percentage of color Doppler area, which was measured quantitatively by a computerized program (Ultrasonic Imaging Tool; Soongsil University, Seoul, Korea). The flow pattern (four-patterns; spotty, linear, branching, marginal) of the vascularity was analyzed. After surgery, tumor angiogenesis was assessed by microvessel density. The relationship between the vascularity on CDUS and microvessel density was statistically analyzed. At unenhanced CDUS, tumoral flow signals were detected in 12 lesions (48%); at contrast-enhanced CDUS, 18 lesions (86%). All These 18 lesions showed increased signals, compared with those at unenhanced CDUS. The percentage color Doppler area was 1.86 {+-} 0.48% at unenhanced CDUS and 5.23 {+-} 1.18% at contrast-enhanced CDUS. The flow patterns before contrast injection were spotty pattern in 11 tumors and linear pattern in one; after contrast injection, spotty in 8, linear in 4, branching in 5, and marginal in one. The tumoral vascularity at contrast-enhanced CDUS showed no significant correlation with microvessel density. Contrast-enhanced CDUS seems to be a valuable tool in the depiction of vascularity and characterization of flow pattern in breast cancer. However, tumoral vascularity on CDUS may not reflect tumoral angiogenesis.

  13. 99m-Tc DMSA scintigraphy and color/power doppler sonography for children pyelonephritis diagnosis and follow-up

    International Nuclear Information System (INIS)

    Hitzel, A.; Manrique, A.; Gardin, I.; Vera, P.; Hitzel, A.; Dacher, J.N.; Manrique, A.; Menard, J.F.; Gardin, I.; Vera, P.; Dacher, J.N.; Liard, A.; Menard, J.F.

    2004-01-01

    Early diagnosis of acute pyelonephritis is essential to avoid scarring development. This study was performed to evaluate capabilities of color/doppler sonography to detect pyelonephritis and to predict scarring when compared with 99m Tc-DMSA scintigraphy. Fifty-seven children were evaluated during pyelonephritis: biology (CRP, creatinine, blood formula), color/power doppler sonography and 99m Tc-DMSA scintigraphy (DMSA1). 7 ± 2 months later, follow-up consisted in biological tests and a 99m 'Tc-DMSA scintigraphy (DMSA2). During pyelonephritis, body temperature, CRP value and neutrophil counts were significantly higher in patients with an abnormal DMSA1 but not in patients with abnormal doppler sonography. When compared with DMSA1, doppler sonography sensitivity and specificity were 80% and 81% respectively. DMSA1 and doppler sonography were concordant in 86% of children with a pyelonephritis. At follow-up, all clinical et biological parameters were normalized. DMSA2 was abnormal in 51% of children. When compared with DMSA2, positive and negative predictive values for scarring of doppler sonography were 57% and 75% respectively. DMSA 1, positive and negative predictive values for scarring were 62% and 100%. In conclusion, color/power doppler sonography is a reliable tool for pyelonephritis diagnosis, but its predictive value for scarring is poor. Negative predictive value of DMSA scintigraphy is excellent. (author)

  14. Visualization of the Origin of the Vertebral Arteries with Color Doppler Sonography

    International Nuclear Information System (INIS)

    Yoon, Seok Hwan; Lee, Won Hong; Lee, Dae Hyung

    2009-01-01

    Atherosclerotic disease at the origin of the vertebral arteries is one of the risk factors for vertebrobasilar ischemic disease. Assessment and visualization of the origin of the vertebral arteries with color doppler sonography is a non-trivial task. The aim of this study is to increase the visualization rate of the origin of the vertebral arteries with color doppler sonography. Color doppler sonography for the vertebral arteries included carotid arteries was performed to 198 patients. We first examined the vertebral artery in the upper neck in the direction of the subclavian artery to distinguish its origin more easily. If the vertebral artery origin was not visualized in natural position, the examiner pushed the transducer toward a clavicle or pushed the shoulder of patient by the other hand. The technical methods for visualization of the vertebral artery origin were classified into three grades: natural position, pushing the transducer, and pushing the shoulder of patient according to the depth (3.0 cm and shallower, deeper than 3.0 cm) of the origin. The origin of the vertebral arteries could be visualized in 97% on the right and in 92% on the left. The origin of the vertebral arteries could be visualized in 98.6%, 1.4%, and 0.0% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at shallower than 3.0 cm on the right side. The origin of the vertebral arteries could be visualized in 81.2%, 14.6%, and 4.2% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at deeper than 3.0 cm on the right side. The origin of the vertebral arteries could be visualized in 85.4%, 10.7%, and 3.9% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at shallower than 3.0 cm on the left side. The origin of the vertebral arteries could be visualized in 55.7%, 30.4%, and 13.9% in natural position, pushing the transducer, and pushing the shoulder of

  15. Renal venous thrombosis in an infant with predisposing thrombotic factors: color Doppler ultrasound and MR evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Argyropoulou, Maria I.; Papadopoulou, Frederica; Nikolopoulos, Pangiotis [Department of Radiology, Medical School, University of Ioannina, 45110, Ioannina (Greece); Giapros, Vassilios I.; Drougia, Aikaterini A.; Andronikou, Styliani [Neonatology Clinic, Medical School, University of Ioannina, 45110, Ioannina (Greece); Vartholomatos, Georgios A. [Department of Haematology, Medical School, University of Ioannina, 45110, Ioannina (Greece)

    2003-08-01

    We report a case of a neonate with hereditary thrombophilia presenting with renal venous thrombosis (RVT). Early color Doppler findings of RVT were lacking venous flow, and the arterial diastolic flow was reversed. This very high-resistance arterial flow is for the first time described in neonatal RVT. Magnetic resonance imaging showed low signal intensity of the renal pyramids on T1- and T2-weighted images, suggesting acute hemorrhage. After intravenous contrast injection, persistent cortical enhancement was observed along with lack of medullary enhancement. Despite the progressive reestablishment of some venous drainage, the kidney showed atrophy and loss of function. (orig.)

  16. Renal venous thrombosis in an infant with predisposing thrombotic factors: color Doppler ultrasound and MR evaluation

    International Nuclear Information System (INIS)

    Argyropoulou, Maria I.; Papadopoulou, Frederica; Nikolopoulos, Pangiotis; Giapros, Vassilios I.; Drougia, Aikaterini A.; Andronikou, Styliani; Vartholomatos, Georgios A.

    2003-01-01

    We report a case of a neonate with hereditary thrombophilia presenting with renal venous thrombosis (RVT). Early color Doppler findings of RVT were lacking venous flow, and the arterial diastolic flow was reversed. This very high-resistance arterial flow is for the first time described in neonatal RVT. Magnetic resonance imaging showed low signal intensity of the renal pyramids on T1- and T2-weighted images, suggesting acute hemorrhage. After intravenous contrast injection, persistent cortical enhancement was observed along with lack of medullary enhancement. Despite the progressive reestablishment of some venous drainage, the kidney showed atrophy and loss of function. (orig.)

  17. Twinkling artifact on color Doppler ultrasound: an advantage or a pitfall?

    Science.gov (United States)

    Ozan, Ebru; Atac, Gokce Kaan; Gundogdu, Sadi

    2016-07-01

    The twinkling artifact (TA) or color comet-tail artifact is characterized by a rapidly changing mixture of red and blue color Doppler signals. Even though many diseases and clinical conditions have been shown to produce this artifact, its source is not clearly understood yet. The TA may provide additional information to gray-scale ultrasound findings in several clinical situations. However, there may be pitfalls to keep in mind. We must first be aware of the TA to benefit from the advantages and avoid the pitfalls. In this review, we aim to give practicing radiologists an overview of the mechanisms and clinical applications of the TA by illustrating sample cases we have encountered.

  18. [Vascular complications following kidney transplant: the role of color-Doppler imaging].

    Science.gov (United States)

    Granata, Antonio; Floccari, Fulvio; Lentini, Paolo; Vittoria, Salvatore; Di Pietro, Fabio; Zamboli, Pasquale; Fiorini, Fulvio; Fatuzzo, Pasquale

    2012-01-01

    The progressive decline in the incidence of graft rejection has made urological, surgical, parenchymal and vascular complications of kidney transplant more frequent. The latter, although accounting for only 5-10% of all post-transplant complications, are a frequent cause of graft loss. Ultrasonography, both in B-mode and with Doppler ultrasound, is an important diagnostic tool in case of clinical conditions which might impair kidney function. Even though ultrasonography is considered fundamental in the diagnosis of parenchymal and surgical complications of the transplanted kidney, its role is not fully understood in case of vascular complications of the graft. The specificity of Doppler ultrasound is very important in case of stenosis of the transplanted renal artery, pseudoaneurysms, arteriovenous fistulas, and thrombosis with complete or partial artery or vein occlusion. Doppler and color determinations present high diagnostic accuracy, which is higher in case of successive measurements performed during the follow-up of the graft. Modern techniques including contrast-enhanced ultrasound increase the diagnostic power of ultrasonography in case of vascular complications of the transplanted kidney, planted kidney.

  19. SELECTIVE AND NONSELECTIVE β-BLOCKERS IN PRIMARY OPEN ANGLE GLAUCOMA THERAPY – RESULTS OF COLOR DOPPLER SONOGRAPHY

    Directory of Open Access Journals (Sweden)

    Vukoslava Maričić-Došen

    2002-12-01

    Full Text Available Background. Primary open angle glaucoma (POAG is a syndrome of progressive optic neuropathy characterized by optic nerve head excavation and visual field defects. Poor correlation between IOP and progression of glaucoma disease sets vascular mechanism in the centre of attention. By Color Doppler sonography, quantification of blood flow changes in vessels, which supply optic nerve head, is possible. We wanted to find out whether there are changes in the circulation of central retinal artery and posterior ciliary arteries in patients with primary open angle glaucoma treated with selective or nonselective β -blockers.Methods. 44 patients (88 eyes were divided into two groups: group 1: 22 patients (44 eyes treated with selective β -blockers (Betaxolol 0.5% and group 2: 22 patients (44 eyes treated with nonselective β -blockers (Timolol 0.5%. Vascular indices (RI, PI were measured in the central retinal artery and posterior ciliary arteries.Results. We found decreased blood flow and increased vascular indices in both groups of patients, statistically significant difference between group 1 and group 2: blood flow velocity was higher and vascular indices were lower in group 1 (Betaxolol 0.5% compared to group 2 (Timolol 0..5%.Conclusions. Selective β -blockers (calcium channel blockers act more vasoactively and neuroprotectively comparing to nonselective β -blockers.

  20. Diagnosis of post-partum ovarian vein thrombophlebitis by color Doppler ultrasonography: about 10 cases.

    Science.gov (United States)

    Giraud, J R; Poulain, P; Renaud-Giono, A; Darnault, J P; Proudhon, J F; Grall, J Y; Mocquet, P Y

    1997-09-01

    Post-partum ovarian vein thrombosis is often overlooked or mistaken for other complications such as endometritis. Color Doppler ultrasonography is a very good diagnostic method when properly indicated and correctly interpreted according to clinical data. This study reports ten cases that were retrospectively studied, during which color Doppler ultrasonography was used. The clinical signs and the results are reviewed. The lesions were clearly visualized in eight of the ten cases; one of the two failures resulted from a methodological fault (uninterpretable result); the other one was due to the lack of experience of the operator and nonrecognition of the clinical signs. Thrombosis appears as a hypoechogenic and tubular image. This type of examination is particularly indicated in the presence of certain clinical signs that were observed in our cases: fever and iliac pain are the main precursor signs, often associated with abdominal meteorism and slow digestive transit; provoked cul-de-sac pain during vaginal probing was the only constant sign, sometimes associated with painful swelling.

  1. Measurement of ciliary beat frequency using Doppler optical coherence tomography.

    Science.gov (United States)

    Lemieux, Bryan T; Chen, Jason J; Jing, Joseph; Chen, Zhongping; Wong, Brian J F

    2015-11-01

    Measuring ciliary beat frequency (CBF) is a technical challenge and difficult to perform in vivo. Doppler optical coherence tomography (D-OCT) is a mesoscopic noncontact imaging modality that provides high-resolution tomographic images and detects micromotion simultaneously in living tissues. In this work we used D-OCT to measure CBF in ex vivo tissue as the first step toward translating this technology to clinical use. Fresh ex vivo samples of rabbit tracheal mucosa were imaged using both D-OCT and phase-contrast microscopy (n = 5). The D-OCT system was designed and built to specification in our lab (1310-nm swept source vertical-cavity surface-emitting laser [VCSEL], 6-μm axial resolution). The samples were placed in culture and incubated at 37°C. A fast Fourier transform was performed on the D-OCT signal recorded on the surface of the samples to gauge CBF. High-speed digital video of the epithelium recorded via phase-contrast microscopy was analyzed to confirm the CBF measurements. The D-OCT system detected Doppler signal at the epithelial layer of ex vivo rabbit tracheal samples suggestive of ciliary motion. CBF was measured at 9.36 ± 1.22 Hz using D-OCT and 9.08 ± 0.48 Hz using phase-contrast microscopy. No significant differences were found between the 2 methods (p > 0.05). D-OCT allows for the quantitative measurement of CBF without the need to resolve individual cilia. Furthermore, D-OCT technology can be incorporated into endoscopic platforms that allow clinicians to readily measure CBF in the office and provide a direct measurement of mucosal health. © 2015 ARS-AAOA, LLC.

  2. Gender-related asymmetric brain vasomotor response to color stimulation: a functional transcranial Doppler spectroscopy study.

    Science.gov (United States)

    Njemanze, Philip C

    2010-11-30

    The present study was designed to examine the effects of color stimulation on cerebral blood mean flow velocity (MFV) in men and women. The study included 16 (8 men and 8 women) right-handed healthy subjects. The MFV was recorded simultaneously in both right and left middle cerebral arteries in Dark and white Light conditions, and during color (Blue, Yellow and Red) stimulations, and was analyzed using functional transcranial Doppler spectroscopy (fTCDS) technique. Color processing occurred within cortico-subcortical circuits. In men, wavelength-differencing of Yellow/Blue pairs occurred within the right hemisphere by processes of cortical long-term depression (CLTD) and subcortical long-term potentiation (SLTP). Conversely, in women, frequency-differencing of Blue/Yellow pairs occurred within the left hemisphere by processes of cortical long-term potentiation (CLTP) and subcortical long-term depression (SLTD). In both genders, there was luminance effect in the left hemisphere, while in men it was along an axis opposite (orthogonal) to that of chromatic effect, in women, it was parallel. Gender-related differences in color processing demonstrated a right hemisphere cognitive style for wavelength-differencing in men, and a left hemisphere cognitive style for frequency-differencing in women. There are potential applications of fTCDS technique, for stroke rehabilitation and monitoring of drug effects.

  3. Color Doppler measurement of blood flow in the inferior thyroid artery in patients with autoimmune thyroid diseases

    International Nuclear Information System (INIS)

    Caruso, Giuseppe; Attard, Marco; Caronia, Aurelio; Lagalla, Roberto

    2000-01-01

    Purpose: The aim of the study is to find out whether the measurement of peak systolic velocity in the inferior thyroid artery (ITA) is a valuable parameter to differentiate autoimmune thyroid diseases (hyper-, normo- or hypofunctional) and to evaluate the efficacy of medical treatment. Material and methods: The ITA of 31 patients (eight with Graves' disease, 23 with subclinical hypothyroidism) was examined with color Doppler and pulsed Doppler. The final diagnosis was obtained by citology and by hormonal and antibodies assays. The patients were monitorized by ultrasound for a period of 8 months. Results: In all the patients with Graves' disease the peak systolic velocity was always over 150 cm/s, while in other autoimmune thyroiditis the peak systolic velocity was within the normal range, and never exceeding 65 cm/s. In the first group, the measurement taken in the ITA showed also the efficacy of the pharmacological treatment earlier and more reliably than the color Doppler pattern obtained in the parenchyma. Conclusions: The color Doppler measurement of the ITA seems to be a promising technique with low-cost and easy approach. In our experience, the color Doppler of the ITA could have a clinical role in the differential diagnosis of diffuse thyroid diseases and in the follow-up of the Graves' disease during medical treatment

  4. Color Doppler measurement of blood flow in the inferior thyroid artery in patients with autoimmune thyroid diseases

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, Giuseppe; Attard, Marco; Caronia, Aurelio; Lagalla, Roberto

    2000-10-01

    Purpose: The aim of the study is to find out whether the measurement of peak systolic velocity in the inferior thyroid artery (ITA) is a valuable parameter to differentiate autoimmune thyroid diseases (hyper-, normo- or hypofunctional) and to evaluate the efficacy of medical treatment. Material and methods: The ITA of 31 patients (eight with Graves' disease, 23 with subclinical hypothyroidism) was examined with color Doppler and pulsed Doppler. The final diagnosis was obtained by citology and by hormonal and antibodies assays. The patients were monitorized by ultrasound for a period of 8 months. Results: In all the patients with Graves' disease the peak systolic velocity was always over 150 cm/s, while in other autoimmune thyroiditis the peak systolic velocity was within the normal range, and never exceeding 65 cm/s. In the first group, the measurement taken in the ITA showed also the efficacy of the pharmacological treatment earlier and more reliably than the color Doppler pattern obtained in the parenchyma. Conclusions: The color Doppler measurement of the ITA seems to be a promising technique with low-cost and easy approach. In our experience, the color Doppler of the ITA could have a clinical role in the differential diagnosis of diffuse thyroid diseases and in the follow-up of the Graves' disease during medical treatment.

  5. Endoscopic Color Doppler Ultrasonographic Evaluation of GastricVarices Secondary to Left-Sided Portal Hypertension

    Science.gov (United States)

    Sato, Takahiro; Yamazaki, Katsu; Kimura, Mutsuumi; Toyota, Jouji; Karino, Yoshiyasu

    2014-01-01

    Gastric varices that arise secondary to the splenic vein occlusion can result in gastrointestinal hemorrhaging. Endoscopic color Doppler ultrasonography (ECDUS) was performed in 16 patients with gastric varices secondary to splenic vein occlusion. This study retrospectively evaluated the role of ECDUS in the diagnosis of gastric varices secondary to splenic vein occlusion. Thirteen patients had co-existing pancreatic diseases: 8 with chronic pancreatitis, 4 with cancer of the pancreatic body or tail and 1 with severe acute pancreatitis. Of the remaining 3 patients, 1 had myeloproliferative disease, 1 had advanced gastric cancer, and the third had splenic vein occlusion due to an obscure cause. The endoscopic findings of gastric varices were: variceal form (F) classified as enlarged tortuous (F2) in 12 cases and large, coil-shaped (F3) in 4 cases, and positive for erosion or red color sign of the variceal surface in 4 cases and negative in 12 cases. ECDUS color flow images of gastric variceal flow clearly depicted a round fundal region at the center, with varices expanding to the curvatura ventriculi major of the gastric body in all 16 cases. The velocities of F3 type gastric varices were significantly higher than those of the F2 type. The wall thickness of varices positive for erosion or red color sign was significantly less than the negative cases. I conclude that ECDUS color flow images of gastric variceal flow depicted specific findings of gastric varices secondary to splenic vein occlusion at the round fundal region at the center, with varices expanding to the curvatura ventriculi major of the gastric body. PMID:26852679

  6. Assessment of the fetomaternal circulation in threatened abortion by transvaginal color Doppler.

    Science.gov (United States)

    Kurjak, A; Zudenigo, D; Predanic, M; Kupesic, S; Funduk, B

    1994-01-01

    Transvaginal color Doppler was used to investigate blood flow in the fetomaternal circulation of 60 women with threatened abortion and 90 women with normal intrauterine pregnancy. The obtained Doppler sonograms were analyzed and the resistance index (RI) was calculated in the maternal circulation, while in the fetal circulation the pulsatility index (PI) was used. There was no significant difference in the RI values of the maternal circulation between women with normal pregnancies and pregnancies complicated by bleeding, but with normal pregnancy outcome (p > 0.05). No differences in RI values of the uterine, arcuate and radial arteries were found between pregnancies with threatened abortion and normal pregnancy outcome and women with abnormal outcome (p > 0.05). In 9 of 21 women with visible retrochorionic hematoma, the RI of the spiral arteries was higher on the hematoma side in comparison to the opposite side (p abortion, the RI of the spiral arteries was lower in comparison to the control group. Such findings could be caused by the vasodilatating products of inflammation which probably exist in such areas. There was no significant difference in terms of the PI of fetal blood vessels between normal pregnancy and threatened abortions with normal outcome, as well as between threatened abortions with normal outcome and subsequent abortions of live fetuses (p > 0.05).

  7. [Ultrasound and color Doppler applications in nephrology. The normal kidney: anatomy, vessels and congenital anomalies].

    Science.gov (United States)

    Meola, Mario; Petrucci, Ilaria; Giovannini, Lisa; Samoni, Sara; Dellafiore, Carolina

    2012-01-01

    Gray-scale ultrasound is the diagnostic technique of choice in patients with suspected or known renal disease. Knowledge of the normal and abnormal sonographic morphology of the kidney and urinary tract is essential for a successful diagnosis. Conventional sonography must always be complemented by Doppler sampling of the principal arterial and venous vessels. B-mode scanning is performed with the patient in supine, prone or side position. The kidney can be imaged by the anterior, lateral or posterior approach using coronal, transverse and oblique scanning planes. Morphological parameters that must be evaluated are the coronal diameter, the parenchymal thickness and echogenicity, the structure and state of the urinary tract, and the presence of congenital anomalies that may mimic a pseudomass. The main renal artery and the hilar-intraparenchymal branches of the arterial and venous vessels should be accurately evaluated using color Doppler. Measurement of intraparenchymal resistance indices (IP, IR) provides an indirect and quantitative parameter of the stiffness and eutrophic or dystrophic remodeling of the intrarenal microvasculature. These parameters differ depending on age, diabetic and hypertensive disease, chronic renal glomerular disease, and interstitial, vascular and obstructive nephropathy.

  8. Color-flow Doppler US usefulness in upper-extremity venous thrombosis

    International Nuclear Information System (INIS)

    Grassi, C.J.; Polak, J.F.

    1988-01-01

    Compared with its application in the leg veins, US has been used infrequently in the axillary-subclavian veins. Using color-flow Doppler US (CFDUS) as the primary means of follow-up, seven patients from a consecutive 120 venograms in the subgroup of effort thrombosis were restudied to compare CFDUS with venography in blinded fashion. In all seven patients, CFDUS allowed prediction of the thrombus location and the collateral veins; swirl (turbulent venous flow) was detected in two patients, asymmetric jugular distention was seen in three, and the normal response on inspiration was vein collapse, The authors experience indicates the CFDUS shows good correlation with axillary-subclavian venography, that blind areas behind the clavicle can be overcome, and that CFDUS may be preferable in follow-up to avoid patient discomfort or contrast material-induced phlebitis

  9. [Elective lymph node dissection in malignant melanoma--status of color Doppler findings].

    Science.gov (United States)

    Omlor, G; Dill-Müller, D; Gross, G; Kautz, G; Schüder, G; Zaun, H; Feifel, G

    1996-01-01

    Since there is still a controversial discussion about the ELND in melanoma patients, the purpose of this prospective study was to optimize the indication concerning ELND by ultrasound examinations. 144 patients with primary melanomas were checked every 3 months after excision. Echomorphologic pattern and intranodal vascularisation in the color-flow Doppler modus provide essential information for differential diagnosis. We found 47 patients (32.6%) with suspicious ultrasound lesions. 50% of these patients had no pathological clinical findings, the histological findings of excised lymph nodes were positive in all cases. It must be emphasized, however, that the group with lymph node metastases included 12 patients with low-risk-melanomas (2 x Tis, 10 x T1 historical control group (141 patients), where ELND was performed routinely in high-risk-patients ( > T2), the incidence of ELND in our hospital decreased more than 50%; at the same time the percentage of detected lymph node metastases increased (twice).

  10. Diagnostic accuracy of color Doppler flow imaging and Duplex US in peripheral arterial disease

    International Nuclear Information System (INIS)

    Karmel, M.I.; Polak, J.F.; Whittemore, A.D.; Mannick, J.A.; Donaldson, M.C.; O'Leary, D.H.

    1988-01-01

    Color Doppler flow imaging (5 MHz) and Duplex US were used in a prospective examination of 154 arterial segments in the lower extremities of 11 symptomatic patients. Each extremity was divided into seven arterial segments (common femoral, profunda femoral, proximal, middle, and distal superficial femoral, and proximal and distal popliteal arteries). Arterial maps were drawn for each patient and compared with the arteriograms. Seventeen significant stenoses and 18 complete occlusions were predicted and confirmed by means of arteriography. Four significant stenoses and four occlusions were predicted and not confirmed. One hundred nine normal arterial segments were correctly predicted. No significant stenoses or occlusions were missed. Prospective identification of the severity and location of disease can help to optimize both the angiographic approach and hospital services utilization

  11. Nutcracker Syndrome Accompanying Pelvic Congestion Syndrome; Color Doppler Sonography and Multislice CT Findings: A Case Report

    International Nuclear Information System (INIS)

    Inal, Mikail; Karadeniz Bilgili, Mihrace Yasemin; Sahin, Safa

    2014-01-01

    Nutcracker syndrome (NCS) is a rare pathology, caused by compression of the left renal vein (LRV) between the abdominal aorta (AA) and the superior mesenteric artery (SMA), due to reduction of the angle between AA and SMA. This leads to LRV varices, left gonadal vein varices and therefore, the pelvic congestion syndrome. For this reason, coexistence of NCS and pelvic congestion syndrome has been described. It manifests by hematuria, proteinuria, and nonspecific pelvic pain secondary to pelvic congestion, dyspareunia and persistent genital arousal. We report a 27-year-old woman who experienced hematuria and left flank pain. The diagnosis of NCS accompanied by pelvic congestion syndrome was missed initially, but later on the diagnosis was made by color Doppler ultrasound, abdominal computed tomography (CT) and CT angiography that were later performed. She refused interventional and surgical treatments, and was lost to follow up

  12. The diagnosis value of color doppler ultrasound in evaluating small renal carcinoma

    International Nuclear Information System (INIS)

    Chen Gaiyi

    2009-01-01

    Objective: To characterize the ultrasound and color doppler imaging of small renal carcinoma. Methods: Ultrasound and color doppler images by convex-probe and high frequency-probe of 24 patients with renal carcinoma confirmed by surgery and histology were analyzed retrospectively. Tumor echo, halo, internal blood flow and peripheral tumor blood flow were observed. Results: Tumor echo in 9 lesions was hyper-echo, in 4 was iso-echoic, in 10 was hypo-echo, and in 1 was echoless. Halo was detected in 9 tumors, and small cyst was detected in 5 tumors. By using the convex-probe, peripheral and internal blood flow signal in 24 tumors were observed. Spot blood follow was detected in 6 tumors, half-circularity blood follow in 18 tumors and no circularity blood follow. Detection rate of internal blood flow was 20.83%. By using the high frequency-probe in 21 tumors, spot blood was detected in 1 tumor, half-circularity blood follow in 14 tumors, circularity blood follow in 6 tumors. Detection rate of internal blood flow was 90.48%. It was not satisfied for high frequency-probe in 3 patients because of obesity. Accordance of the diagnosis by high frequency-probe ultrasound was 90.48% and 91.67% by CT (P > 0.05). Conclusion: Detection of renal carcinoma is sensitive by ultrasound. The high frequency-probe is significant sensitive to detect blood follow in renal carcinoma and is helpful to correct diagnosis of renal carcinoma. (authors)

  13. Significance of 'Bridging vessel sign' on color Doppler ultrasound in diagnosis of uterine subserosal leiomyoma

    International Nuclear Information System (INIS)

    Lee, Jin Hee; Lee, Jung Hee; Sohn, Chul Ho; Woo, Seung Koo; Kim, Jung Sik

    2002-01-01

    To evaluate the usefulness of the 'bridging vessel sign' in differentiating uterine subserosal leiomyoma from other pelvic masses mimicking leiomyoma on color Doppler ultrasound. Histologically (n=58) and clinically (n=1) proven 59 masses from 55 women were included in this study. Histologic diagnoses included leiomyoma (n=32) and various kinds of other masses (n=27). On gray scale ultrasound, the size of tumor and presence of the ovaries were recorded. On color Doppler ultrasound, the presence of 'bridging vessel sign', which was defined as a linear vessel demonstrated between the mass and the uterus was documented. Uterine subserosal leiomyoma was diagnosed on the basis of finding this sign, and the diagnostic accuracy of this sign in differentiating subserosal leiomyoma from other pelvic tumors was calculated. In addition, the diagnostic accuracy of this sign combined with the visibility of theopsilateral ovary was compared. The size of subserosal leiomyomas ranged from 4.2 to 22.1 cm (mean, 8.3 cm) while the size of other pelvic masses, from 4.6 to 21.5 cm (mean, 9.6 cm). The 'bridging vessel sign' was demonstrated in thirty of 32 leiomyomas and in three of 27 other pelvis masses. The sensitivity, specificity, accuracy, positive predictive value, and negative value of the 'bridging vessel sign' in the diagnosis of subserosal leiomyoma were 93.8%, 99.9%, 91.5%, 90.9% and 92.3%, respectively. The detection of the ipsilateral ovary was possible in 14 of 30 women with leiomyomas and in four of 25 women with other pelvic masses. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of this finding in the diagnosis of subserosal leiomyoma were 46.7%, 84.0%, 63.6%, 77.8%, and 56.8%, respectively. 'Bridging vessel sign' can be an useful finding in the differential diagnosis of subserosal leiomyomas from other pelvic masses mimicking leiomyoma.

  14. Color Doppler US of normal cerebral venous sinuses in neonates: a comparison with MR venography

    International Nuclear Information System (INIS)

    Miller, Elka; Daneman, Alan; Doria, Andrea S.; Blaser, Susan; Traubici, Jeffrey; Jarrin, Jose; Shroff, Manohar; Moineddin, Rahim; Moore, Aideen

    2012-01-01

    Color Doppler US (CDUS) has been used for evaluation of cerebral venous sinuses in neonates. However, there is very limited information available regarding the appearance of superficial and deep normal cerebral venous sinuses using CDUS and the specificity of the technique to rule out disease. To determine the specificity, inter-modality and inter-reader agreement of color Doppler US (CDUS). To evaluate normal cerebral venous sinuses in neonates in comparison to MR venography (MRV). Newborns undergoing a clinically indicated brain MRI were prospectively evaluated. All underwent a dedicated CDUS of the cerebral venous sinuses within 10 h (mean, 3.5 h, range, and 2-7.6 h) of the MRI study using a standard protocol. Fifty consecutive neonates participated in the study (30 males [60%]; 25-41 weeks old; mean, 37 weeks). The mean time interval between the date of birth and the CDUS study was 19.1 days. No cases showed evidence of thrombosis. Overall agreement for US reading was 97% (range, 82-100%), for MRV reading, 99% (range, 96-100%) and for intermodality, 100% (range, 96-100%). Excellent US-MRI agreement was noted for superior sagittal sinus, cerebral veins, straight sinus, torcular Herophili, sigmoid sinus, superior jugular veins (94-98%) and transverse sinuses (82-86%). In 10 cases (20%), MRV showed flow gaps whereas normal flow was demonstrated with US. Visualization of the inferior sagittal sinus was limited with both imaging techniques. Excellent reading agreement was noted for US, MRV and intermodality. CDUS is highly specific to rule out cerebral venous thrombosis in neonates and holds potential for clinical application as part of clinical-laboratory-imaging algorithms of pre/post-test probabilities of disease. (orig.)

  15. “Focal thyroid inferno” on color Doppler ultrasonography: A specific feature of focal Hashimoto's thyroiditis

    International Nuclear Information System (INIS)

    Fu, Xianshui; Guo, Limei; Zhang, Huabin; Ran, Weiqiang; Fu, Peng; Li, Zhiqiang; Chen, Wen; Jiang, Ling; Wang, Jinrui; Jia, Jianwen

    2012-01-01

    Purpose: To evaluate color-Doppler features predictive of focal Hashimoto's thyroiditis. Materials and methods: A total of 521 patients with 561 thyroid nodules that underwent surgeries or gun biopsies were included in this study. These nodules were divided into three groups: focal Hashimoto's thyroiditis (104 nodules in 101 patients), benignity other than focal Hashimoto's thyroiditis (73 nodules in 70 patients), and malignancy (358 nodules in 350 patients). On color Doppler sonography, four vascularity types were determined as: hypovascularity, marked internal flow, marked peripheral flow and focal thyroid inferno. The χ 2 test was performed to seek the potential vascularity type with the predictive ability of certain thyroid pathology. Furthermore, the gray-scale features of each nodule were also studied. Results: The vascularity type I (hypovascularity) was more often seen in focal Hashimoto's thyroiditis than other benignity and malignancy (46% vs. 20.5% and 19%). While the type II (marked internal flow) showed the opposite tendency (26.9% [focal Hashimoto's thyroiditis] vs. 45.2% [other benignity] and 52.8% [malignancy]). However, type III (marked peripheral flow) was unable to predict any thyroid pathology. Importantly, type IV (focal thyroid inferno) was exclusive to focal Hashimoto's thyroiditis. All 8 type IV nodules appeared to be solid, hypoechoic, and well-defined. Using “focal thyroid inferno” as an indicator of FHT, the diagnostic sensitivity and specificity were 7.7% and 100% respectively. Conclusions: The vascularity type of “focal thyroid inferno” is specific for focal Hashimoto thyroiditis. Recognition of this particular feature may avoid unnecessary interventional procedures for some solid hypoechoic thyroid nodules suspicious of malignancy.

  16. Magnetic resonance angiography in renal grafts. Comparison with color Doppler echography

    International Nuclear Information System (INIS)

    Yanagisawa, Takayoshi; Otsubo, Osamu; Nozaki, Harushige

    1995-01-01

    We studied relationship between magnetic resonance angiography (MRA) of renal graft and renal graft function in 14 renal transplantations (10 from living donors, 4 from cadaveric donors). MRA was performed on 0.3-T permanent magnet system (MRP 7000, HITACHI, JAPAN) using 2 dimensional time of flight technique (FOV: 350 mm 2 , RT: 60 msec, ET: 10 msec, FA: 90deg, Slice: volumes 60, thickness 4 mm, overlap 1 mm). As for parameters of renal graft function, we evaluated color doppler echography (CD) of transplanted renal artery, renal blood flow (RBF), velocity of interlobar artery (ILA) and serum creatinine level (S-Cr). CD, RBF and velocity of ILA were visualized and measured by duplex color doppler echosystem (EUB-565A, HITACHI, JAPAN). Depending on visualization of transplanted renal artery, MRA was graded into 3 groups (MA Grade 3: visualization of ILA, MA Grade 2: visualization of segmental artery and the first branch but no visualization of ILA, MA Grade 1: visualization of main renal artery only). Likewise, visualization of CD was graded into 3 groups (CD Grade 3: good visualization of arcuate artery (AA) and ILA, CD Grade 2: poor visualization of AA but good visualization of ILA, CD Grade 1: poor visualization of ILA). The MRA grading had a very significant correlation (r=0.79, p<0.001) with the CD grading. As for RBF and velocity of ILA, the RBF of MA Grade 3 group (n=8) was significantly (p<0.05) higher than the MA Grade 2 group (n=4) and the MA Grade 1 group (n=2), and the velocity of ILA of MA Grade 3 group was also higher than the above groups but not significantly. Furthermore, the S-Cr of MA Grade 3 was significantly (p<0.05) lower than the others. These results showed that MRA of renal graft had a qualitative index of renal graft function. (author)

  17. Does color Doppler sonography improve the clinical assessment of patients with acute scrotum?

    International Nuclear Information System (INIS)

    Pepe, Pietro; Panella, Paolo; Pennisi, Michele; Aragona, Francesco

    2006-01-01

    Introduction and objectives: Our experience concerning the use of color Doppler sonography (CDS) in the differential diagnosis of acute scrotum is reported. Material and methods: From July 2000 to July 2005, 155 patients (median 17.2 years) were admitted with a diagnosis of acute scrotum (unilateral in 150 cases, bilateral in 5). Along with a careful anamnesis and the physical exam, all patients underwent a CDS study of the scrotal content using a sonograph GE Logiq 500 with a multifrequency (7.5-10 MHz) linear probe Small Part. The following CDS parameters were evaluated: intensity of the color-power signal on the testicular parenchyma and on the epididymis; systolic peak velocity (SPV) and telediastolic velocity (TDV) in correspondence of the gonadal hilum. Ultrasound and flowmetry parameters registered on the painful testis were compared with those registered on the healthy controlateral testis. The reduction/absence versus the increase of color-power signal in the parenchyma and the reduction/absence versus the increase of SPV and TDV in the centripetal intratesticular arteries were considered presumptive of testicular torsion versus orchiepididymitis. Results: The results only refer to the 150 patients (300 testis) with acute monolateral scrotum. The clinical picture and the physical exam suggested a torsion of the spermatic cord in 40 cases, a spontaneous de-torsion in 5, an orchiepididymitis in 80, a blunt scrotal trauma in 15, a bulky epididymal cyst or a hydrocele in 4 and a testicular pain of unknown etiology in the remaining 6 cases. Standard US was pathological in 95 patients (63.3%); CDS was pathologic in 70 patients and in 42 of them suggested a testicular torsion. Fifty-three patients underwent surgical exploration: among 42 patients with a presumptive diagnosis of testicular torsion, the diagnosis was confirmed in 22 cases, no anomaly was found in 16 cases and in 4 patients a torsion of testicular appendix was found. The rupture of the tunica

  18. Análisis de perforantes de la epigástrica inferior profunda con Angio TC 3D, Eco Doppler color y Doppler simple de ultrasonidos en colgajo DIEP: resultados preliminares Analysis of deep inferior epigastric perforating vessels with 3D CT angiography, color Doppler ultrasonography and Doppler in diep flaps: preliminary results

    Directory of Open Access Journals (Sweden)

    J. Castro García

    2008-09-01

    Full Text Available Nuestro objetivo es la validación de la Angio TC tridimensional como herramienta de planificación de los colgajos DIEP, comparándolo con el Doppler de ultrasonidos (US y eco Doppler color. Entre enero de 2006 y marzo de 2007 se realiza en 11 pacientes (13 DIEP un estudio comparativo prospectivo entre el Doppler de US, eco Doppler color y Angio TC con reconstrucción tridimensional, utilizando como dato de referencia los hallazgos intraoperatorios. En dicho proceso se localiza la mejor perforante que pueda servir como pedículo al colgajo DIEP en función de su localización, calibre, trayecto y relaciones anatómicas con respecto al músculo. La Angio TC con reconstrucción tridimensional, demuestra una especificidad del 100% (IC 95% 75.3-100 lo que le convierte en una prueba con un alto valor predictivo positivo y una excelente herramienta en la planificación de los colgajos de perforantes. El eco Doppler color determinó, que tan sólo en un 46,1% (IC 95% 19,2-74,9 de los pacientes, la perforante seleccionada por la prueba de forma preoperatoria, coincidía con la perforante elegida en quirófano. Con el Doppler de US, en un 30,8 % (IC 95% 9,1-61,4 de los colgajos estudiados, coincidía la mejor perforante escogida de forma preoperatoria, con los hallazgos obtenidos tras la disección del colgajo. En el presente estudio, la Angio TC tridimensional se ha mostrado como una técnica con una gran especificidad que proporciona valiosa información, sólo comparable con la disección anatómica y por delante de pruebas como el Doppler de ultrasonidos y el eco Doppler color.The aim of this report, is to validate the Angio-CT technique with three-dimentional reconstruction as a preoperative planning tool, after comparison with Doppler ultrasound and color- Duplex. Between january 2006 and march 2007, we studied 11 consecutive patients (13 DIEP in whom a prospective comparative followed up was performed comparing, the findings observed using

  19. Spectral color Doppler in the diagnosis and follow-up of Graves` disease; Ruolo dell`eco color Doppler e dell`analisi flussimetrica nella diagnosi e nel follow-up della malattia dei Graves

    Energy Technology Data Exchange (ETDEWEB)

    Sponza, Massimo; Bertolotto, Michele; Ricci, Claudio [Ospedale di Cattinara, Trieste (Italy). Istituto di Medicina Clinica; Fabris, Bruno; Armini, Lorenzo [Ospedale di Cattinara, Trieste (Italy). Istituto di Radiologia

    1997-04-01

    Hyperthyroidism in Graves` disease is caused by the presence of circulating autoantibodies to the THS receptors on the thyroid cells. Thyroid-suppression therapy prevents hormone production directly, without affecting the pathogenetic process. They performed color Doppler US of the thyroid gland and pulsed Doppler analysis of thyroid artery flow in 21 patients with Graves` disease before and during medical treatment. US results were compared with those of a control group of 40 healthy subjects and correlated with the values of thyroid hormones, TSH and thyroid microsomal and thyroglobulin antibodies. The thyroid gland was hypo vascularized in the control group. Pulsed Doppler examination of the thyroid arteries exhibited peak systolic velocity of PSV 20 {+-} 4 cm/s, diastolic velocity of 8 {+-} 1 cm/s, and resistive index of 0.60 {+-} 0.04. The thyroid gland of Graves` disease patients was hyper vascularized. Pulsed Doppler examination of the thyroid arteries exhibited peak systolic velocity (PSV = 51 {+-} 12 cm/s), end diastolic velocity (VD = 15 {+-} 4 cm/s) and resistive index (RI = 0.71 {+-} 0.04) significantly higher than in normal subjects (p < 0.001). Circulating thyroid hormones and flow parameters normalized after 6-8 months of medical therapy (PSV = 20 {+-} 6 cm/s, VD = 9 {+-} 3 cm/s, RI = 0.58 {+-} 0.07). The color Doppler patterns normalized only in a patient with normal TSH and antibodies. Sampling of the thyroid arteries proved more repeatable than sampling of parenchymal vessels.

  20. Usefulness of color and pulsed Doppler's in the evaluation of surgical portosystemic shunts in pediatric patients; Utilidad del Doppler color y pulsado en la valoracion de los shunts portosistemicos quirurgicos en la edad pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Berrocal, T.; Prieto, C.; Cortes, P.; Rodriguez, R.; Pastor, I. [Hospital Universitario La Paz. Madrid (Spain)

    2003-07-01

    Portosystemic shunts are performed to relieve symptomatic portal hypertension symptomatic or removal pressure in hepatic vascularisation in patients with Budd-Chiari's syndrome. Most surgical portosystemic shunts can be suitably studied by means of ultrasound scan complemented by color and pulsed Dopplers, proved one understands the hemodynamics of the surgical procedures involved. This article demonstrates the usefulness and limitations of the ultrasound scan Duplex Doppler in the evaluation of portosystemic shunts performed on pediatric patients. Pulsed Doppler provides information regarding the nature and direction of blood flow. Color doppler is capable of directly revealing the shunt and, in most cases, permits the anastomosis to be located. The types of shunts that appear include proximal and distal spleno-renal, portocaval and mesocaval. Types of vascular connections are illustrated,s well as expected post-surgical blood flow direction in affected vessels. The ultrasound scanning technique is discussed, as well as the criteria for determining vascular permeability. Also highlighted are the advantages, limitations and diagnostic difficulties associated with the different forms of Doppler. (Author) 17 refs.

  1. Validation of color Doppler sonography for evaluating relative displacement between the flexor tendon and subsynovial connective tissue.

    Science.gov (United States)

    Tat, Jimmy; Kociolek, Aaron M; Keir, Peter J

    2015-04-01

    A common pathologic finding in carpal tunnel syndrome is fibrosis and thickening of the subsynovial connective tissue. This finding suggests an etiology of excessive shear forces, with relative longitudinal displacement between the flexor tendon and adjacent subsynovial connective tissue. The purpose of this study was to validate color Doppler sonography for measurement of tendon displacement over time. Eight unmatched fresh frozen cadaver arms were used to evaluate color Doppler sonography for measurement of tendon displacement. The middle flexor digitorum superficialis tendon was moved through a physiologic excursion of 20 mm at 3 different tendon velocities (50, 100, and 150 mm/s). We found that color Doppler sonography provided accurate measurement of tendon displacement, with absolute errors of -0.05 mm (50 mm/s), -1.24 mm (100 mm/s), and -2.36 mm (150 mm/s) on average throughout the tendon excursion range. Evaluating relative displacement between the tendon and subsynovial connective tissue during finger flexion-extension movements also offered insight into the gliding mechanism of the subsynovial connective tissue. During flexion, we observed a curvilinear increase in relative displacement, with greater differential motion at the end range of displacement, likely due to the sequential stretch of the fibrils between successive layers of the subsynovial connective tissue. In extension, there was a linear return in relative displacement, suggesting a different unloading mechanism characterized by uniform relaxation of fibrils. We demonstrated the validity of color Doppler displacement for use in the evaluation of relative motion. Color Doppler sonography is useful in our understanding of the behavior of the subsynovial connective tissue during tendon excursion, which may elucidate the role of finger motion in the etiology of shear injury. © 2015 by the American Institute of Ultrasound in Medicine.

  2. Gold nanorods as a contrast agent for Doppler optical coherence tomography.

    Directory of Open Access Journals (Sweden)

    Bo Wang

    Full Text Available To investigate gold nanorods (GNRs as a contrast agent to enhance Doppler optical coherence tomography (OCT imaging of the intrascleral aqueous humor outflow.A serial dilution of GNRs was scanned with a spectral-domain OCT device (Bioptigen, Durham, NC to visualize Doppler signal. Doppler measurements using GNRs were validated using a controlled flow system. To demonstrate an application of GNR enhanced Doppler, porcine eyes were perfused at constant pressure with mock aqueous alone or 1.0×10(12 GNR/mL mixed with mock aqueous. Twelve Doppler and volumetric SD-OCT scans were obtained from the limbus in a radial fashion incremented by 30°, forming a circular scan pattern. Volumetric flow was computed by integrating flow inside non-connected vessels throughout all 12 scans around the limbus.At the GNR concentration of 0.7×10(12 GNRs/mL, Doppler signal was present through the entire depth of the testing tube without substantial attenuation. A well-defined laminar flow profile was observed for Doppler images of GNRs flowing through the glass capillary tube. The Doppler OCT measured flow profile was not statistically different from the expected flow profile based upon an autoregressive moving average model, with an error of -0.025 to 0.037 mm/s (p = 0.6435. Cross-sectional slices demonstrated the ability to view anterior chamber outflow ex-vivo using GNR-enhanced Doppler OCT. Doppler volumetric flow measurements were comparable to flow recorded by the perfusion system.GNRs created a measureable Doppler signal within otherwise silent flow fields in OCT Doppler scans. Practical application of this technique was confirmed in a constant pressure ex-vivo aqueous humor outflow model in porcine eyes.

  3. The role of trapped bubbles in kidney stone detection with the color Doppler ultrasound twinkling artifact

    Science.gov (United States)

    Simon, Julianna C.; Sapozhnikov, Oleg A.; Kreider, Wayne; Breshock, Michael; Williams, James C., Jr.; Bailey, Michael R.

    2018-01-01

    The color Doppler ultrasound twinkling artifact, which highlights kidney stones with rapidly changing color, has the potential to improve stone detection; however, its inconsistent appearance has limited its clinical utility. Recently, it was proposed stable crevice bubbles on the kidney stone surface cause twinkling; however, the hypothesis is not fully accepted because the bubbles have not been directly observed. In this paper, the micron or submicron-sized bubbles predicted by the crevice bubble hypothesis are enlarged in kidney stones of five primary compositions by exposure to acoustic rarefaction pulses or hypobaric static pressures in order to simultaneously capture their appearance by high-speed photography and ultrasound imaging. On filming stones that twinkle, consecutive rarefaction pulses from a lithotripter caused some bubbles to reproducibly grow from specific locations on the stone surface, suggesting the presence of pre-existing crevice bubbles. Hyperbaric and hypobaric static pressures were found to modify the twinkling artifact; however, the simple expectation that hyperbaric exposures reduce and hypobaric pressures increase twinkling by shrinking and enlarging bubbles, respectively, largely held for rough-surfaced stones but was inadequate for smoother stones. Twinkling was found to increase or decrease in response to elevated static pressure on smooth stones, perhaps because of the compression of internal voids. These results support the crevice bubble hypothesis of twinkling and suggest the kidney stone crevices that give rise to the twinkling phenomenon may be internal as well as external.

  4. The role of trapped bubbles in kidney stone detection with the color Doppler ultrasound twinkling artifact.

    Science.gov (United States)

    Simon, Julianna C; Sapozhnikov, Oleg A; Kreider, Wayne; Breshock, Michael; Williams, James C; Bailey, Michael R

    2018-01-09

    The color Doppler ultrasound twinkling artifact, which highlights kidney stones with rapidly changing color, has the potential to improve stone detection; however, its inconsistent appearance has limited its clinical utility. Recently, it was proposed stable crevice bubbles on the kidney stone surface cause twinkling; however, the hypothesis is not fully accepted because the bubbles have not been directly observed. In this paper, the micron or submicron-sized bubbles predicted by the crevice bubble hypothesis are enlarged in kidney stones of five primary compositions by exposure to acoustic rarefaction pulses or hypobaric static pressures in order to simultaneously capture their appearance by high-speed photography and ultrasound imaging. On filming stones that twinkle, consecutive rarefaction pulses from a lithotripter caused some bubbles to reproducibly grow from specific locations on the stone surface, suggesting the presence of pre-existing crevice bubbles. Hyperbaric and hypobaric static pressures were found to modify the twinkling artifact; however, the simple expectation that hyperbaric exposures reduce and hypobaric pressures increase twinkling by shrinking and enlarging bubbles, respectively, largely held for rough-surfaced stones but was inadequate for smoother stones. Twinkling was found to increase or decrease in response to elevated static pressure on smooth stones, perhaps because of the compression of internal voids. These results support the crevice bubble hypothesis of twinkling and suggest the kidney stone crevices that give rise to the twinkling phenomenon may be internal as well as external.

  5. Pulsed-wave tissue Doppler and color tissue Doppler echocardiography: calibration with M-mode, agreement, and reproducibility in a clinical setting

    DEFF Research Database (Denmark)

    Olsen, Niels Thue; Jons, Christian; Fritz-Hansen, Thomas

    2009-01-01

    BACKGROUND: Myocardial velocities can be measured with both pulsed-wave tissue Doppler (PWTD) and color tissue Doppler (CTD) echocardiography. We aimed to (A) to explore which of the two methods better approximates true tissue motion and (B) to examine the agreement and the reproducibility...... of the two methods in a routine clinical setting. METHODS: For Study A, the displacements of 63 basal myocardial segments from 13 patients were examined with M-mode and compared with the velocity-time integral of PWTD and CTD velocities. For Study B, the basal lateral segments from 58 patients were examined...... with PWTD and CTD, and the peak myocardial velocities during systole (Sm), early diastole (Em), and late diastole (Am) were measured. RESULTS: Study A: CTD-based measurements of displacement were 12% lower than M-mode measurements (95% CI: -18%; -6%). PWTD velocity-time integrals measured at the outer edge...

  6. Corpus luteum blood flow in normal and abnormal early pregnancy: evaluation and analysis with transvaginal color and pulsed doppler sonography

    International Nuclear Information System (INIS)

    Tang Xiaoyi; Lin Meifang; Zheng Meirong; Liang Xiaoxian; Liu Jianfeng

    2005-01-01

    Objective: Detecting and assessment the corpus luteum blood flow in normal and abnormal early pregnancy. Methods: Using transvaginal color and pulse Doppler sonography, we detected 215 pregnant women including 150 normal intrauterine pregnancies, 25 abortion, 29 ectopic pregnancies, and then recorded corpus luteum blood flow feature and the blood flow indexes (Vmax, RI and PI). Results: 1) Corpus luteum was successfully identified in 148 cases out of 150 of normal early pregnancies, 25 cases out of 26 of threatened abortion; 22 cases out of 29 of ectopic pregnancy. 2) Three groups shared the same feature of Color Doppler imaging: a circumferential rim around the entire corpus luteum. 3) The flow index revealed mean PVS, RI and PI had no statistical difference in normal and abnormal early pregnancy; The mean PVS was lower in ectopic pregnancy than in normal pregnancy (P<0.05), while PI and PR had no characteristic in ectopic pregnancy group compared with the indexes obtained in normal pregnancy group. Conclusion: The corpus luteum can be precisely identified in most pregnancy using transvaginal color Doppler and manifests a characterized rim Doppler imaging. PVS may help in differentiating the ectopic pregnancy from normal early pregnancy. (authors)

  7. Ultrasonography and color Doppler of proximal gluteal enthesitis in juvenile idiopathic arthritis: a descriptive study

    Directory of Open Access Journals (Sweden)

    Thomsen Carsten

    2011-08-01

    Full Text Available Abstract Background The presence of enthesitis (insertional inflammation in patients with juvenile idiopathic arthritis (JIA is difficult to establish clinically and may influence classification and treatment of the disease. We used ultrasonography (US and color Doppler (CD imaging to detect enthesitis at the small and deep-seated proximal insertion of the gluteus medius fascia on the posterior iliac crest where clinical diagnosis is difficult. The findings in JIA patients were compared with those obtained in healthy controls and with the patients' MRI results. Methods Seventy-six proximal gluteus medius insertions were studied clinically (tenderness to palpation of the posterior iliac crest and by US and CD (echogenicity, thickness, hyperemia in 38 patients with JIA and in 38 healthy controls, respectively (median age 13 years, range 7-18 years. In addition, an additional MRI examination of the sacroiliac joints and iliac crests was performed in all patients. Results In patients with focal, palpable tenderness, US detected decreased echogenicity of the entheses in 53% of the iliac crests (bilateral in 37% and unilateral in 32%. US also revealed significantly thicker entheses in JIA patients compared to healthy controls (p Conclusions According to US, the gluteus medius insertion was thicker in JIA patients than in controls, and it was hypoechoic (enthesitis in about half of the patients. These findings may represent chronic, inactive disease in some of the patients, because there was only limited Doppler flow and MRI contrast enhancement. The present study indicates that US can be useful as an adjunct to clinical examination for improved assessment of enthesitis in JIA. This may influence disease classification, ambition to treat, and choice of treatment regimen.

  8. A rare case of OEIS complex –newer approach to diagnosis of exstrophy bladder by color doppler and its differentiation from simple omphalocele

    Directory of Open Access Journals (Sweden)

    Kavita Aneja

    2017-01-01

    Full Text Available The objective of this article is to present a new approach to diagnose and differentiate similar ventral masses by color Doppler. Two cases of ventral masses, a rare case of OEIS complex (Omphalocele-exstrophy-imperforate anus-spinal defects with unusual presentation of exstrophy bladder and another of simple omphalocele, were studied by color Doppler for diagnosis and differentiation between the nature of similar masses. Ventral mass with absent bladder, normal kidneys, and normal amniotic fluid index raised the suspicion of exstrophy bladder. Color Doppler depicting altered intrafetal course of umbilical arteries and umbilical arteries coursing along the sides of ventral mass substantiated the diagnosis. The spatial relation between umbilical artery and aorta (which has no mention in the current literature in sagittal view has been identified as an acute angle in a normal fetus and coined as “K angle” arbitrarily by the author. Color Doppler reveals altered (widened “K angle” in exstrophy bladder compared to normal fetuses. Other combined anomalies pointed to the diagnosis of OEIS complex. The second case of simple omphalocele depicts normal intrafetal course of umbilical arteries and normal acute umbilical artery–aorta angle (K angle on color Doppler. Color Doppler aids the early diagnosis of ventral defects. New method by umbilical artery-aorta angle (K angle assessment on color Doppler helps differentiate exstrophy bladder from omphalocele.

  9. Magneto-optic Doppler analyzer: a new instrument to measure mesopause winds

    Science.gov (United States)

    Williams, Bifford P.; Tomczyk, Steven

    1996-11-01

    The magneto-optic Doppler analyzer (MODA) is a new type of passive optical instrument that one can use to measure the Doppler shift of the sodium nightglow emitted at approximately 91 km near the mesopause. From this measurement, horizontal wind signatures are inferred. The MODA is based on a sodium vapor magneto-optic filter that provides inherent wavelength stability at a low cost. The instrument has been used to take nightly zonal and meridional wind measurements since October 1994 at Niwot Ridge, Colorado (40 N, 105 W). We obtained an internally consistent wind signal and measured the semidiurnal tide for several seasons.

  10. IRAS colors of carbon stars - An optical spectroscopic test

    International Nuclear Information System (INIS)

    Cohen, M.; Wainscoat, R.J.; Walker, H.J.; Volk, K.; Schwartz, D.E.

    1989-01-01

    Optical spectra are obtained of 57 photographic counterparts to IRAS sources not previously studied spectroscopically, and expected on the basis of their IRAS colors to be M or C type stars. Confirmed carbon stars are found only in a restricted range of 12-25 index, and constitute a striking vertical sequence in the 12-25-60 micron color-color diagram. This sequence is in accord with evolutionary models for AGB stars that convert M into C stars by dredge-up, and follow loops in the color-color plane. Optically visible and optically invisible carbon stars occupy different color-color locations consistent with their representations of different evolutionary states in the life of relatively low-mass stars. 16 refs

  11. Comparison of brucella and non-specific epididymorchitis: gray scale and color Doppler ultrasonographic features

    International Nuclear Information System (INIS)

    Ozturk, Adil; Ozturk, Ebru; Zeyrek, Fadile; Onur, Kahraman; Sirmatel, Ocal; Kat, Nurcan

    2005-01-01

    Objective: The aim of this study is to find out if it is possible to differentiate between brucellar and non-specific epididymorchitis by comparing ultrasonography (US) and color Doppler ultrasonography (CDUS) findings. Material and methods: Fifty-six patients diagnosed to have epididymorchitis both clinically and ultrasonographically were included to study. All of the patients were investigated serologically for brucella. Twenty-eight of those patients were admitted brucella epididymorchitis because of high agglutinations titers for brucella. The other 28 patients were admitted non-specific epididymorchitis because of normal agglutinations titers for brucella. Testicular size, echogenicity, hydrocele, internal echoes and/or septations within hydrocele, and scrotal skin thickness of normal and involved testis were compared by ultrasonography. Besides, pick systolic velocity, end diastolic velocity, resistive index and pick systolic velocity ratio values were measured by bilateral testicular color Doppler ultrasonography in both groups. When the p-value is <0.05, the difference between groups is accepted as statistically significant. Results: Thickening of scrotal skin was seen in 17 of 28 patients with brucella epididymorchitis (BEPO) (67%) and in 25 of 28 patients with non-specific epididymorchitis (NEPO) (89.2%) (p < 0.01). There was no difference between groups regarding presence of hydrocele. However hydrocele seen in all patients was anechoic except for two patients (8.6%). Hydrocele seen in 18 of 22 patients with BEPO and hydrocele had internal echogenicity or septation (p < 0.001). Sizes of testes and epididymis were found to be increased in involved testis compared to normal testis. Testes of all patients with NEPO were homogenous with decreased echogenicity except for five patients (17.8%). However, 23 patients with BEPO (82%) found to have heterogenous testis (p < 0.001). Spectral measurements showed increased PSV and EDV values and decreased RI values in

  12. Comparison of brucella and non-specific epididymorchitis: gray scale and color Doppler ultrasonographic features

    Energy Technology Data Exchange (ETDEWEB)

    Ozturk, Adil [Department of Radiology, Harran University School of Medicine, Arastirma ve Uygulama Hastanesi, TR-63100 Sanliurfa (Turkey)]. E-mail: ozturka26@hotmail.com; Ozturk, Ebru [Department of Radiology, Harran University School of Medicine, Arastirma ve Uygulama Hastanesi, TR-63100 Sanliurfa (Turkey); Zeyrek, Fadile [Department of Microbiology, Harran University School of Medicine, Sanliurfa (Turkey); Onur, Kahraman [Department of Urology, SSK Sanliurfa Hastanesi, Sanliurfa (Turkey); Sirmatel, Ocal [Department of Radiology, Harran University School of Medicine, Arastirma ve Uygulama Hastanesi, TR-63100 Sanliurfa (Turkey); Kat, Nurcan [Department of Radiology, Harran University School of Medicine, Arastirma ve Uygulama Hastanesi, TR-63100 Sanliurfa (Turkey)

    2005-11-01

    Objective: The aim of this study is to find out if it is possible to differentiate between brucellar and non-specific epididymorchitis by comparing ultrasonography (US) and color Doppler ultrasonography (CDUS) findings. Material and methods: Fifty-six patients diagnosed to have epididymorchitis both clinically and ultrasonographically were included to study. All of the patients were investigated serologically for brucella. Twenty-eight of those patients were admitted brucella epididymorchitis because of high agglutinations titers for brucella. The other 28 patients were admitted non-specific epididymorchitis because of normal agglutinations titers for brucella. Testicular size, echogenicity, hydrocele, internal echoes and/or septations within hydrocele, and scrotal skin thickness of normal and involved testis were compared by ultrasonography. Besides, pick systolic velocity, end diastolic velocity, resistive index and pick systolic velocity ratio values were measured by bilateral testicular color Doppler ultrasonography in both groups. When the p-value is <0.05, the difference between groups is accepted as statistically significant. Results: Thickening of scrotal skin was seen in 17 of 28 patients with brucella epididymorchitis (BEPO) (67%) and in 25 of 28 patients with non-specific epididymorchitis (NEPO) (89.2%) (p < 0.01). There was no difference between groups regarding presence of hydrocele. However hydrocele seen in all patients was anechoic except for two patients (8.6%). Hydrocele seen in 18 of 22 patients with BEPO and hydrocele had internal echogenicity or septation (p < 0.001). Sizes of testes and epididymis were found to be increased in involved testis compared to normal testis. Testes of all patients with NEPO were homogenous with decreased echogenicity except for five patients (17.8%). However, 23 patients with BEPO (82%) found to have heterogenous testis (p < 0.001). Spectral measurements showed increased PSV and EDV values and decreased RI values in

  13. Noticeable positive Doppler effect on optical bistability in an N-type active Raman gain atomic system

    International Nuclear Information System (INIS)

    Chang Zeng-Guang; Zhang Jing-Tao; Niu Yue-Ping; Gong Shang-Qing

    2012-01-01

    We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity. It is shown that the Doppler effect can greatly enhance the dispersion and thus create the bistable behaviour or greatly increase the bistable region, which has been known as the positive Doppler effect on optical bistability. In addition, we find that a positive Doppler effect can change optical bistability from the hybrid dispersion-gain type to a dispersive type

  14. Granulomatous Prostatitis: Gray-scale Transrectal Ultrasonography and Color Doppler Ultrasonography Findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Jung; Lim, Joo Won; Lee, Dong Ho; Ko, Young Tae; Kim, Eui Jong [Kyung Hee University Medical Center, Seoul (Korea, Republic of)

    2007-12-15

    We report here three cases of granulomatous prostatitis. All cases were confirmed by a transrectal ultrasonography (TRUS)-guided core biopsy of the prostate. Two cases received intravesical BCG therapy for a bladder tumor, and one case had no known predisposing condition. Gray-scale TRUS showed low echoic nodules in the outer gland in all cases. Color Doppler ultrasonography (CDUS) showed several dot-like blood flows within the low echoic nodules in two cases and several dot-like blood flows and short linear blood flows within the low echoic nodules in one case. Gray-scale TRUS findings of granulomatous prostatitis are similar to findings of prostate cancer. On CDUS, several dot-like blood flows or short linear blood flows were noted within the low echoic nodules in patients with granulomatous prostatitis. If low echoic nodules with dot-like or short linear blood flows are noted in patients with genitourinary tract tuberculosis or previous BCG therapy, granulomatous prostatitis should be included in the differential diagnosis. However, a prostatic biopsy is required for a final diagnosis

  15. MR imaging of multiple fibroadenoma in breast: comparison with color doppler images and histologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Soo Young; Yang, Ik; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Ahn, Hye Kyung [Hallym Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-10-01

    To understand the different signal intensities seen on contrast enhanced magnetic resonance imaging (MRI) in multiple fibroadenoma of the breast, and to compare these with color Doppler ultrasonographic (CDUS) and histologic findings. MRI (1.0 Tesla, TIWI, T2WI, 3D-gradient echo dynamic contrast enhancement study) findings of 24 histologically proven cases of fibroadenoma in five patients were evaluated and compared with the histologic components (myxoid, adenomatous, fibrous). In addition, vascular flow, as seen on CDUS and histologic section, was compared. The observed degree of signal intensity waw classified into three groups, as follows: negative, 8.3%, mild to moderate, 54.2%; marked, 37.5%. On histologic section, the greater the fibrotic component, the higher the intensity of MRI enhancement, the greater the glandular component, and the intensity. CDUS showed vascular flow in only one tumor larger than 3cm in diameter. Vascular patterns of tumors on CDUS were dots in mass and detouring pattern, but in this case and in strongly enhanced cases, tumor vascularity-as seen on histologic section-showed no significant increase. Different signal intensities seen on contrast enhanced MRI in multiple fibroadenoma of the breast may be related more to the amount of glandular and fibrotic component than to increased tumor vascularity.

  16. Primary chronic venous insufficiency of the lower extremities: preoperative color duplex Doppler ultrasound study

    International Nuclear Information System (INIS)

    Selfa, S.; Diago, T.; Ricart, M.; Chulia, R.; Martin, F.

    2000-01-01

    To asses the role of color duplex Doppler ultrasound (CDU) in the preoperative study of patients with varicose veins in lower extremities. We employed CDU to examine varicose veins in 342 lower limbs, assessing reflux in saphenous veins (SV), deep venous system (DVS) and perforating veins (PV). We analyzed the relationship between the anatomical extent of the reflux and the clinical findings. Insufficiency of the superficial venous system alone was uncommon, occurring in only 10.8% of the limbs examined. Reflux was observed in SV and PV in 48.2% of the legs. It was detected in all three systems in 29.2% of cases. The presence of reflux in more than one system and more than one value was associated with increased clinical severity. The site of venous reflux in lower extremities with varicose veins varies. Greater clinical severity is observed in the presence of more marked reflux in the DVS and PV. CDU provides anatomic and functional data on the three venous systems of the lower limbs, allowing an individualized therapeutic surgery. Preoperative localization of incompetent PV by means of CDU facilities their ligation. CDU is the technique of choice for the preoperative examination of the venous systems of patients with varicose veins. (Author)

  17. MR imaging of multiple fibroadenoma in breast: comparison with color doppler images and histologic findings

    International Nuclear Information System (INIS)

    Chung, Soo Young; Yang, Ik; Park, Hai Jung; Lee, Yul; Chung, Bong Wha; Ahn, Hye Kyung

    1997-01-01

    To understand the different signal intensities seen on contrast enhanced magnetic resonance imaging (MRI) in multiple fibroadenoma of the breast, and to compare these with color Doppler ultrasonographic (CDUS) and histologic findings. MRI (1.0 Tesla, TIWI, T2WI, 3D-gradient echo dynamic contrast enhancement study) findings of 24 histologically proven cases of fibroadenoma in five patients were evaluated and compared with the histologic components (myxoid, adenomatous, fibrous). In addition, vascular flow, as seen on CDUS and histologic section, was compared. The observed degree of signal intensity waw classified into three groups, as follows: negative, 8.3%, mild to moderate, 54.2%; marked, 37.5%. On histologic section, the greater the fibrotic component, the higher the intensity of MRI enhancement, the greater the glandular component, and the intensity. CDUS showed vascular flow in only one tumor larger than 3cm in diameter. Vascular patterns of tumors on CDUS were dots in mass and detouring pattern, but in this case and in strongly enhanced cases, tumor vascularity-as seen on histologic section-showed no significant increase. Different signal intensities seen on contrast enhanced MRI in multiple fibroadenoma of the breast may be related more to the amount of glandular and fibrotic component than to increased tumor vascularity

  18. Determination of Testicular Blood Flow in Camelids Using Vascular Casting and Color Pulsed-Wave Doppler Ultrasonography

    OpenAIRE

    Kutzler, Michelle; Tyson, Reid; Grimes, Monica; Timm, Karen

    2011-01-01

    We describe the vasculature of the camelid testis using plastic casting. We also use color pulsed-wave Doppler ultrasonography to measure testicular blood flow and compare the differences between testicular blood flow in fertile and infertile camelids. The testicular artery originates from the ventral surface of the aorta, gives rise to an epididymal branch, and becomes very tortuous as it approaches the testis. Within the supratesticular arteries, peak systolic velocity (PSV) was higher in f...

  19. Color Doppler ultrasound evaluation of asphyxial neonatal left ventricular function and its correlation with target organ damage

    Directory of Open Access Journals (Sweden)

    Cheng-Cai Chen

    2017-01-01

    Full Text Available Objective: To study the color Doppler ultrasound parameters of asphyxial neonatal left ventricular function and the correlation with target organ damage. Methods: Normal neonates, mildly asphyxial neonates and severely asphyxial neonates born in our hospital between January 2014 and December 2015 were selected as the control group (n = 46, mild asphyxia group (n = 37 and severe asphyxia group (n = 23 respectively. On the 1st day after birth, color Doppler ultrasound was used to evaluate left ventricular function, and serum was collected to determine myocardial tissue injury, brain tissue injury and brain tissue metabolism indexes. Results: Color Doppler ultrasound parameters cardiac output (CO, ejection fraction (EF and left ventricular fraction shortening (FS as well as serum folate and vitamin B12 content of mild asphyxia group and severe asphyxia group were significantly lower than those of control group (P<0.05 while serum creatine kinase isoenzyme (CK-MB, troponin I (cTnI, troponin T (cTnT, S100B, neuron-specific enolase (NSE, creatine kinase BB (CK-BB, glycogen phosphorylase BB (GPBB, and homocysteine (Hcy content were significantly higher than those of control group (P<0.05; CO, FS and EF as well as serum folate and vitamin B12 content of severe asphyxia group were significantly lower than those of mild asphyxia group (P<0.05 while serum CK-MB, cTnT, cTnI, S100B, NSE, CK-BB, GPBB and Hcy content were significantly higher than those of mild asphyxia group (P<0.05. Conclusions: Color Doppler ultrasound can accurately assess asphyxial neonatal left ventricular function damage degree and is closely related to myocardial tissue injury and brain tissue injury degree.

  20. Sub-Doppler cooling in reduced-period optical lattice geometries

    International Nuclear Information System (INIS)

    Berman, P.R.; Raithel, G.; Zhang, R.; Malinovsky, V.S.

    2005-01-01

    It is shown that sub-Doppler cooling occurs in an atom-field geometry that can lead to reduced-period optical lattices. Four optical fields are combined to produce a 'standing wave' Raman field that drives transitions between two ground state sublevels. In contrast to conventional Sisyphus cooling, sub-Doppler cooling to zero velocity occurs when all fields are polarized in the same direction. Solutions are obtained using both semiclassical and quantum Monte Carlo methods in the case of exact two-photon resonance. The connection of the results with conventional Sisyphus cooling is established using a dressed state basis

  1. Cavernous hemangioma of liver: a comparative study of MRI and color Doppler ultrasound (with 58 case report)

    International Nuclear Information System (INIS)

    Luan Zhiyong; Xu Weidong; Wang Jiazhong

    2006-01-01

    Objective: To evaluate MRI and the color Doppler ultrasound in the diagnosis of cavernous hemangioma of liver. Methods: In total 58 patients with hemangioma of liver underwent dynamic enhanced MRI and the color Doppler ultrasound examination. The imaging manifestations obtained by both modalities were comparatively studied. Result: Highly echoic lesions were revealed in 36 cases out of 58; low echoic lesions were noted in 8; and in 14 cases the tumors were of mixed echoic. On T 1 WI the lesions were hypo- or slightly hypo-intense; while on T 2 WI they were hyper- or slightly hyper-intense. The nidi were hyper-intense on T 2 WI of CRE array. On enhanced scan the lesions were quickly fully enhanced in 25 cases out of 58. Peripheral nodular enhancement was seen in 19 cases, and centered spreading enhancement was demon- strated in 14 cases. On delayed scan remarkable homogenous enhancement was observed in all cases. Conclusion: The bigger size has the hemangioma, the smaller highly echoic proportion and bigger mixed echoic or poorly echoic proportion will be found within the lesions. More peripheral nodular enhancement will be revealed on enhanced MRI scan when the tumor size is getting larger, in which the proportion of quickly fully enhancement will decrease gradually. Ultrasound is better than MRI in the evaluation of the liver hemangioma smaller than 3 cm in diameter. MRI is superior to color Doppler ultrasound in diagnosing the lesion larger' than 3 cm in diameter. (authors)

  2. Experimental study on blood flow patterns through the phantoms of the intracranial arterial aneurysms using color Doppler imaging

    International Nuclear Information System (INIS)

    Chung, Tae Sub; Jeong, Eun Kee; Rhim, Yoon Chul; Kim, Sung Bin; Lee, Dong Hoon; Kim, Dae In

    1994-01-01

    The occurrence, growth, thrombosis, and rupture of intracranial saccular aneurysms can be directly related to the effect of hemodynamic forces. We developed the phantom flow models and compared with the computer simulation program to analyse the flow pattern and hemodynamics that might be responsible for the intracranial arterial aneurysms. We designed the arterial phantoms of three major sites of intracranial arterial aneurysm ; 1) basilar artery tip, 2) internal carotid artery bifurcation, 3) curved area of internal carotid artery. Flow patterns in the aneurysmal portion of phantoms were evaluated with color Doppler system on the connection with automatic closed type of circulation system. Then, we compared the results with computer simulation. The hemodynamic characteristics of the phantoms were identical with those obtained by computerisation's. Three distinct zones of flow were identified by color Doppler studies on the aneurysm of the curved area of an internal carotid artery : 1) an inflow zone entering the aneurysm at the distal aspect of its orifice, 2) an outflow zone exiting the aneurysm at the proximal aspect of its orifice, 3) a central slow vortex.However, the phantoms of basilar artery tip and artery bifurcation showed a direct inflow stream at the dome of an aneurysm. Flow dynamics in the various phantoms of the aneurysms can be successfully evaluated with color Doppler imaging, and were consistent with those predicted by computer simulations

  3. [The diagnostic performance of color Doppler ultrasonography for newborn four cases of midgut volvulus accompanied by intestinal malrotation].

    Science.gov (United States)

    Ikeshima, Yukari; Hisano, Katsuya; Morisawa, Takeshi; Inoue, Kozue; Shimamoto, Masahiro; Koujitani, Toshiaki; Yonetani, Masahiko; Yasufuku, Masao

    2014-03-01

    Midgut volvulus accompanied by intestinal malrotation is classified as a surgical emergency disease of the newborn, which emerges with the bilious vomiting or melena. This report presents four patients of this disease in our hospital, evaluated by color Doppler ultrasonography before surgical operation. All four patients were presented by bilious vomiting at the onset. By color Doppler ultrasonography method, the whirlpool sign which is the view of intestine and superior mesenteric vein rotated around with the axis of superior mesenteric artery, were shown in all cases. This whirlpool sign led to the diagnosis of midgut volvulus accompanied by intestinal malrotation. Intestinal contrast imaging was tested in three patients for the purpose of confirming the diagnosis. Repair of the volvulus and a ladd operation was performed in all four patients, without the excision of intestine because of no intestinal ischemic change. The clinical courses of four cases were good, and all patients were discharged within 17 days. Early diagnosis and timely surgical operation are essential for decreasing the possibility of occurring intestinal ischemic changes and improving clinical outcome after surgical operation. We propose that color Doppler ultrasonography is the powerful tool for the diagnosis of this disease, especially for the newborn, for whom the available diagnostic tests are limited.

  4. Normal reference values for vertebral artery flow volume by color Doppler sonography in Korean adults

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Hyun Sook; Cha, Jang Gyu; Park, Seong Jin; Joh, Joon Hee; Park, Jai Soung; Kim, Dae Ho; Lee, Hae Kyung; Ahn, Hyun Cheol [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2003-09-15

    Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume. This study was to establish the reference values for the flow volume of the vertebral artery using color Doppler sonography in the normal Korea adults. Thirty five normal Korea adults without any underlying disease including hypertension, hyperlipidemia, diabetes, heart disease, obesity (body mas index>30), or carotid artery stenosis was included. There were 17 males and 18 females, age ranged from 20 to 53 years (average=32.86 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segment, usually at C5-6 level, bilaterally. The flow volume (Q) was calculated. (Q=time averaged mean velocity x cross sectional area of vessel) A lower Flow velocity and smaller vessel diameter were measured on the right side compared to those of the left side, resulting in a lower flow volume. The calculated flow volumes using the equation were 77.0 +- 39.7 ml/min for the right side and 127.6 +- 71.0 ml/min for the left side (p=0.0001) while the net vertebral artery flow volume was 204.6 +- 81.8 ml/min. Decrease in the vertebral artery flow volume was statistically significant with advanced age. (r=-0.36, p=0.032). Vertebral artery blood flow volume was 191.20 +- 59.19 ml/min in male, and 217.28 +- 98.67 ml/min in female (p=0.6). The normal range for the net vertebral artery flow volume defined by the 5th to 95th percentiles was between 110.06 and 364.1 ml/min. The normal range for the net vertebral artery flow volume was between 110.06 and 364.1 ml/min. Vertebral artery flow volume decreased with the increase of age. However, gender did not affect the blood flow volume.

  5. The transabdominal chorionic villus sampling puncture guided by color Doppler ultrasound during early pregnancy

    International Nuclear Information System (INIS)

    Liang Weixiang; Chen Zhiyi; Yuan Wenlin; Cai Kuan; Zhu Junlin; Wang Weiqun; Chen Xia

    2008-01-01

    Objective: To study the operation of chorionic villus sampling (CVS) guided by color Doppler ultrasound (CDU) via abdomen puncture during early pregnancy and investigate the advertences during the operation. Methods: CVS guided by CDU probe via abdomen puncture were operated on 28 pregnant women who had the indications of antenatal diagnosis. CDU was used to observe the implantation position of the fo1iaceous villis and help setting mark of the puncture point and puncture range on body surface before operation. The needle was punctured under real-time ultrasound guidance and villis were aspirated during the operation: The choice of the right time of puncture and the operation skills were emphasized in the study. Results: The CVS puncture approach should be set through CDU ob servation, which attend to avoid the surrounding blood vessels, intestinal canal and surrounding important organs. The puncture point should be chosen in a point where lobif0rmed villis distributed wider and with a larger scope. The operations were performed from 10 to13 weeks of pregnancy, with an average of 11 weeks. Among these 28 cases, 9.6 were successfully drawn materials in one time, 1 in twice and l failure, with the total ratio of achievement was 96.4%. For all the cases, fetal heart pulsating could be seen by real-time CDU observation fight after the operation, and no larger hematoma echo in the placental site occurred. Ultrasound reexamined one week after the operation, fetal heart pulsation could be found in all cases, and no abortion cases occurred after regular follow-up in 25 continued pregnant patients. Conclusion: Abdominal CVS puncture guided by CDU probe is conveniently operated, safe and available in clinic. It is an important method for antenatal diagnosis during early pregnancy. The puncture localization, skills and the time are the key points for the success in obtaining the materials. (authors)

  6. Correlation of Color Doppler with Multidetector CT Angiography Findings in Carotid Artery Stenosis

    Directory of Open Access Journals (Sweden)

    Živorad N. Savic

    2010-01-01

    Full Text Available The aim of this paper was to examine the correlation between the Color Doppler ultrasound (CD-US and multidetector CT angiography (MDCTA diagnostic methods, and to define the degree and extent of stenosis in patients with internal carotid artery stenosis. This was a cross-sectional study with a consecutive series of patients. All US examinations were always carried out by the same physician-angiologist, while all CT examinations were always carried out by the same physician-radiologist. Both worked independently from each other. The stenosis area was measured at the narrowest point by NASCET criteria for US/CT. Peak systolic velocity (PSV over 210 cm/sec and end diastolic velocity (EDV over 110 cm/sec criteria were applied for stenoses with lumen narrowed over 70%, while PSV under 130 cm/sec and EDV under 100 cm/sec criteria were applied for those with lumen narrowed under 70%. A total of 124 carotid arteries were observed; namely, 89 narrowed and 68 surgically treated. All patients were reviewed by US and then by MDCTA; patients with 70–99% stenosis underwent surgery. The correlation coefficient between stenosis degree measured by US and MDCTA was 0.922; p 0.05. The US and CT matching level for stenoses from 70 to 99% was very high (κ = 0.778, p < 0.01. In conclusion, there is a highly significant statistical correlation among both diagnostic methods when measuring stenosis degree and extent. US is more dependent on the physician, while MDCTA is more objective and independent from the physician. We think it would be appropriate to undertake an MDCTA exam for those patients who are candidates for carotid endarterectomy.

  7. Color Doppler evaluation of the ocular arterial flow changes in chronic obstructive pulmonary disease

    International Nuclear Information System (INIS)

    Ozer, Tulay; Altin, Remzi; Ugurbas, Suat Hayri; Ozer, Yetkin; Mahmutyazicioglu, Kamran; Kart, Levent

    2006-01-01

    Purpose: To evaluate the hemodynamic changes in the extraocular orbital vessels of the patients with chronic obstructive pulmonary disease (COPD), using color Doppler ultrasonography (CDU) technique, and to compare the results with those of healthy control subjects. Methods: Forty-five patients with COPD and 17 healthy control subjects were included in this study. Patients with COPD were classified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Fifteen patients of stage I COPD (mild airflow limitation), stage II COPD (worsening airflow limitation) or stage III COPD (severe airflow limitation) were enrolled into Group I, II and III, respectively. End tidal carbon dioxide (EtCO 2 ), peripheral oxygen saturation (SpO 2 ), pulse rate (PR) and respiratory rate (RR) were measured by using capnograph/pulse oximeter in all patients. Measurements were performed in only one randomly chosen eye of each participant. The peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index (RI) were measured in the ophthalmic artery (OA), central retinal artery (CRA), lateral short posterior ciliary artery (LPCA) and medial short posterior ciliary artery (MPCA), using CDU technique. Results: The PSV measurements of the OA were significantly higher in Groups II and III compared to control group (p 2 with PSV (r = 0.53, p < 0.01) and EDV (r = 0.51, p < 0.01) of the OA. Statistically significant correlations were also found for the SpO2 with RI (r = -0.34, p < 0.05) in the OA. Conclusion: We concluded that COPD is associated with impaired retrobulbar hemodynamics, especially in the ophthalmic artery. Moreover, central retinal and posterior ciliary arteries with increased resistance are also found to be affected when compared with healthy control eyes

  8. Basal ganglia perfusion using dynamic color Doppler sonography in infants with hypoxic ischemic encephalopathy receiving therapeutic hypothermia: a pilot study.

    Science.gov (United States)

    Faingold, Ricardo; Cassia, Guilherme; Morneault, Linda; Saint-Martin, Christine; Sant'Anna, Guilherme

    2016-10-01

    The objective of this study was to evaluate the cerebral perfusion of the basal ganglia in infants with hypoxic-ischemic encephalopathy (HIE) receiving hypothermia using dynamic color Doppler sonography (CDS) and investigate for any correlation between these measurements and survival. Head ultrasound (HUS) was performed with a 9S4 MHz sector transducer in HIE infants submitted to hypothermia as part of their routine care. Measurements of cerebral perfusion intensity (CPI) with an 11LW4 MHz linear array transducer were performed to obtain static images and DICOM color Doppler videos of the blood flow in the basal ganglia area. Clinical and radiological data were evaluated retrospectively. The video images were analyzed by two radiologists using dedicated software, which allows automatic quantification of color Doppler data from a region of interest (ROI) by dynamically assessing color pixels and flow velocity during the heart cycle. CPI is expressed in cm/sec and is calculated by multiplying the mean velocity of all pixels divided by the area of the ROI. Three videos of 3 seconds each were obtained of the ROI, in the coronal plane, and used to calculate the CPI. Data are presented as mean ± SEM or median (quartiles). A total of 28 infants were included in this study: 16 male, 12 female. HUS was performed within the first 48 hours of therapeutic hypothermia treatment. CPI values were significantly higher in the seven non-survivors when compared to survivors (0.226±0.221 vs . 0.111±0.082 cm/sec; P=0.02). Increased perfusion intensity of the basal ganglia area within the first 48 of therapeutic hypothermia treatment was associated with poor outcome in neonates with HIE.

  9. Color Doppler, power Doppler and B-flow ultrasound in the assessment of ICA stenosis: Comparison with 64-MD-CT angiography

    International Nuclear Information System (INIS)

    Clevert, D.A.; Johnson, T.; Flach, P.M.; Strautz, T.I.; Becker, C.; Reiser, M.; Jung, E.M.; Ritter, G.; Gallegos, M.T.; Kubale, R.

    2007-01-01

    The purpose of this study is to investigate the diagnostic potential of color-coded Doppler sonography (CCDS), power-Doppler (PD) and B-flow ultrasound in assessing the degree of extracranial internal carotid artery (ICA) stenosis in comparison to CT-angiography (MD-CTA). Thirty-two consecutive patients referred for CTA with 41 ICA-stenoses were included in this prospective study. MD-CTA was performed using a 64 row scanner with a CTDIvol of 13.1 mGy/cm. In CTA, CCDS, PD and B-flow, the degree of stenosis was evaluated by the minimal intrastenotic diameter in comparison to the poststenotic diameter. Two radiologists performed a quantitative evaluation of the stenoses in consensus blinded to the results of ultrasound. These were correlated to CTA, CCDS, PD and B-flow, intraoperative findings and clinical follow-up. Grading of the stenoses in B-flow ultrasound outperformed the other techniques in terms of accuracy with a correlation coefficient to CTA of 0.88, while PD and CCDS measurements yield coefficients of 0.74 and 0.70. Bland-Altman analysis additionally shows a very little bias of the three US methods between 0.5 and 3.2 %. There is excellent correlation (coefficient 0.88, CI 0.77-0.93) with 64-MD-CTA and B-flow ultrasound in terms of accuracy for intrastenotic and poststenotic diameter. Duplex sonography is useful for screening purposes. (orig.)

  10. Application of low-coherence optical fiber Doppler anemometry to fluid-flow measurement: optical system considerations

    Science.gov (United States)

    Boyle, William J. O.; Grattan, Kenneth T. V.; Palmer, Andrew W.; Meggitt, B. T.

    1991-08-01

    A fiber optic Doppler anemometric (FODA) sensor using an optical delay cavity technique and having the advantage of detecting velocity rather than simple speed is outlined. In this sensor the delay in a sensor cavity formed from light back-reflected from a fiber tip (Fresnel reflection) and light back-reflected from particles flowing in a fluid is balanced by the optical delay when light from this sensor cavity passes through a reference cavity formed by a combination of the zero and first diffraction orders produced by a Bragg cell inserted into the optical arrangement. The performance of an experimental sensor based on this scheme is investigated, and velocity measurements using the Doppler shift data from moving objects are presented. The sensitivity of the scheme is discussed, with reference to the other techniques of fluid flow measurement.

  11. Absence of Doppler signal in transcranial color-coded ultrasonography may be confirmatory for brain death: A case report

    Directory of Open Access Journals (Sweden)

    Mehmet Akif Topçuoğlu

    2015-08-01

    Full Text Available Transcranial Doppler ultrasonography (TCD is a valuable tool for demonstrating cerebral circulatory arrest (CCA in the setting of brain death. Complete reversal of diastolic flow (to-and-fro flow and systolic spikes in bilateral terminal internal carotid arteries and vertebrobasilar circulation are considered as specific sonogram configurations supporting the diagnosis of CCA. Because of the possibility of sonic bone window impermeability, absence of any waveform in TCD is not confirmatory for CCA unless there is documentation of disappearance of a previously well detected signal by the same recording settings. Transcranial color-coded sonography (TCCS with B-mode imaging can reliably detect adequacy of bone windows with clarity contralateral skull and ipsilateral planum temporale visualization. Therefore, absence of detectable intracranial Doppler signal along with available ultrasound window in TCCS can confirm clinical diagnosis of brain death. We herein discuss this entity from the frame of a representative case.

  12. Doppler optical coherence microscopy and tomography applied to inner ear mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Page, Scott; Freeman, Dennis M. [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States); Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States); Ghaffari, Roozbeh [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States)

    2015-12-31

    While it is clear that cochlear traveling waves underlie the extraordinary sensitivity, frequency selectivity, and dynamic range of mammalian hearing, the underlying micromechanical mechanisms remain unresolved. Recent advances in low coherence measurement techniques show promise over traditional laser Doppler vibrometry and video microscopy, which are limited by low reflectivities of cochlear structures and restricted optical access. Doppler optical coherence tomography (DOCT) and Doppler optical coherence microscopy (DOCM) both utilize a broadband source to limit constructive interference of scattered light to a small axial depth called a coherence gate. The coherence gate can be swept axially to image and measure sub-nanometer motions of cochlear structures throughout the cochlear partition. The coherence gate of DOCT is generally narrower than the confocal gate of the focusing optics, enabling increased axial resolution (typically 15 μm) within optical sections of the cochlear partition. DOCM, frequently implemented in the time domain, centers the coherence gate on the focal plane, achieving enhanced lateral and axial resolution when the confocal gate is narrower than the coherence gate. We compare these two complementary systems and demonstrate their utility in studying cellular and micromechanical mechanisms involved in mammalian hearing.

  13. Middle cerebral artery vasospasm: transcranial color-coded duplex sonography versus conventional nonimaging transcranial Doppler sonography.

    Science.gov (United States)

    Swiat, Maciej; Weigele, John; Hurst, Robert W; Kasner, Scott E; Pawlak, Mikolaj; Arkuszewski, Michal; Al-Okaili, Riyadh N; Swiercz, Miroslaw; Ustymowicz, Andrzej; Opala, Grzegorz; Melhem, Elias R; Krejza, Jaroslaw

    2009-03-01

    To prospectively compare accuracies of transcranial color-coded duplex sonography (TCCS) and transcranial Doppler sonography (TCD) in the diagnosis of middle cerebral artery (MCA) vasospasm. Prospective blinded head-to-head comparison TCD and TCCS methods using digital subtraction angiography (DSA) as the reference standard. Department of Radiology in a tertiary university health center in a metropolitan area. Eighty-one consecutive patients (mean age, 53.9 +/- 13.9 years; 48 women). The indication for DSA was subarachnoid hemorrhage in 71 patients (87.6%), stroke or transient ischemic attack in five patients (6.2%), and other reasons in five patients (6.2%). The MCA was graded as normal, narrowed 50% using DSA. The accuracy of ultrasound methods was estimated by total area (Az) under receiver operator characteristic curve. To compare sensitivities of ultrasound methods, McNemar's test was used with mean velocity thresholds of 120 cm/sec for the detection of less advanced, and 200 cm/sec for the more advanced MCA narrowing. Angiographic MCA narrowing 50% in 10 of 135 arteries. Accuracy of TCCS was insignificantly higher than that of TCD in the detection of 50% narrowing, total Az for mean velocity being 0.83 +/- 0.05, 0.77 +/- 0.05, and 0.95 +/- 0.02, 0.86 +/- 0.08, respectively. Sensitivity of TCCS at commonly used threshold of 120 cm/sec for less advanced MCA spasm was significantly better than that of TCD at similar specificity, 55% vs. 39%, p = 0.038, whereas at a threshold of 200 cm/sec used for more advanced spasm, sensitivities and specificities of both methods were not different. The accuracy of TCCS and TCD is similar, but TCCS is more sensitive than TCD in the detection of MCA spasm. Sensitivity of both techniques in the detection of mild and more advanced spasm using 120 cm/sec and 200 cm/sec thresholds, respectively, is poor; however, a larger sample is required to increase precision of our sensitivity estimates.

  14. Normal reference values for vertebral artery flow volume by color Doppler sonography in Korean adults

    International Nuclear Information System (INIS)

    Hong, Hyun Sook; Cha, Jang Gyu; Park, Seong Jin; Joh, Joon Hee; Park, Jai Soung; Kim, Dae Ho; Lee, Hae Kyung; Ahn, Hyun Cheol

    2003-01-01

    Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume. This study was to establish the reference values for the flow volume of the vertebral artery using color Doppler sonography in the normal Korea adults. Thirty five normal Korea adults without any underlying disease including hypertension, hyperlipidemia, diabetes, heart disease, obesity (body mas index>30), or carotid artery stenosis was included. There were 17 males and 18 females, age ranged from 20 to 53 years (average=32.86 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segment, usually at C5-6 level, bilaterally. The flow volume (Q) was calculated. (Q=time averaged mean velocity x cross sectional area of vessel) A lower Flow velocity and smaller vessel diameter were measured on the right side compared to those of the left side, resulting in a lower flow volume. The calculated flow volumes using the equation were 77.0 ± 39.7 ml/min for the right side and 127.6 ± 71.0 ml/min for the left side (p=0.0001) while the net vertebral artery flow volume was 204.6 ± 81.8 ml/min. Decrease in the vertebral artery flow volume was statistically significant with advanced age. (r=-0.36, p=0.032). Vertebral artery blood flow volume was 191.20 ± 59.19 ml/min in male, and 217.28 ± 98.67 ml/min in female (p=0.6). The normal range for the net vertebral artery flow volume defined by the 5th to 95th percentiles was between 110.06 and 364.1 ml/min. The normal range for the net vertebral artery flow volume was between 110.06 and 364.1 ml/min. Vertebral artery flow volume decreased with the increase of age. However, gender did not affect the blood flow volume.

  15. The application of color Doppler flow imaging in the diagnosis and therapeutic effect evaluation of erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Xu-Jun Xuan

    2016-01-01

    Full Text Available We aim to investigate the correlations between hemodynamic parameters, penile rigidity grading, and the therapeutic effects of phosphodiesterase type 5 inhibitors using color Doppler flow imaging after intracavernosal injection in patients with erectile dysfunction. This study involved 164 patients. After intracavernosal injection with a mixture of papaverine (60 mg, prostaglandin E 1 (10 mg, and lidocaine (2%, 0.5-1 ml, the penile vessels were assessed using color Doppler flow imaging. Penile rigidity was classified based on the Erection Hardness Score system as Grades 4, 3, 2 or 1 (corresponding to Schramek Grades V to II. Then, the patients were given oral sildenafil (50-100 mg and scored according to the International Index of Erectile Function (IIEF-5 questionnaire. The number of patients with penile rigidities of Schramek Grades II to V was 14, 18, 21, and 111, respectively. The IIEF-5 score was positively correlated with the refilling index of the penile cavernosal artery (r = 0.79, P< 0.05, the peak systolic velocity (r = 0.45, P< 0.05, and penile rigidity (r = 0.75, P< 0.05, and was negatively correlated with the end diastolic velocity (r = −0.74, P< 0.05. For patients with erectile dysfunction, both the IIEF-5 score after sildenafil administration, which is correlated with penile rigidity, and the hemodynamic parameters detected using color Doppler flow imaging may predict the effects of phosphodiesterase type 5 inhibitor treatment and could provide a reasonable model for the targeted-treatment of erectile dysfunction.

  16. A Fourier Optical Model for the Laser Doppler Velocimeter

    DEFF Research Database (Denmark)

    Lading, Lars

    1972-01-01

    The treatment is based on a fourier optical model. It is shown how the various configurations (i.e. ldquodifferential moderdquo and reference beam mode with both one and two incident beams) are incorporated in the model, and how it can be extended to three dimensions. The particles are represented...... filtering ability vanishes as the aperture size converges towards zero. The results based on fourier optics are compared with the rough estimates obtainable by using the "antenna formular" for heterodyning (ArΩr≈λ2)....

  17. Contribution of spiral artery blood flow changes assessed by transvaginal color Doppler sonography for predicting endometrial pathologies

    Directory of Open Access Journals (Sweden)

    Suna Kabil Kucur

    2013-01-01

    Full Text Available ive: To investigate the diagnostic value of blood flow measurements in spiral artery by transvaginal color Doppler sonography (CDS in predicting endometrial pathologies.Methods: Ninety-seven patients presenting with abnormal uterine bleeding and requiring endometrial assessment were included in this prospective observational study. Endometrial thickness, structure and echogenicity were recorded. Pulsatility index (PI and resistive index (RI of the spiral artery were measured by transvaginal CDS. Endometrial sampling was performed for all subjects. Sonographic and hystopathologic findings were compared.Results: The histopathological diagnoses were as follows; 39 cases (40.2% endometrial polyp, 9 cases (9.3% endometrial hyperplasia, 10 cases (10.3 submucous myoma, 7 cases (7.2% endometrium cancer, and 32 cases (33% nonspecific findings. The spiral artery PI in endometrium cancer group was highly significantly lower than other groups (p<0.01. The spiral artery RI was also significantly lower in the patients with malignant histology (p<0.05. Conclusion: Endometrial pathologies are associated significantly with endometrial spiral artery Doppler changes.Key words: Spiral artery, Doppler ultrasonography, endometrium

  18. Coherent optical transients observed in rubidium atomic line filtered Doppler velocimetry experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fajardo, Mario E., E-mail: mario.fajardo@eglin.af.mil; Molek, Christopher D.; Vesely, Annamaria L. [Air Force Research Laboratory, Munitions Directorate, Ordnance Division, Energetic Materials Branch, AFRL/RWME, 2306 Perimeter Road, Eglin AFB, Florida 32542-5910 (United States)

    2015-10-14

    We report the first successful results from our novel Rubidium Atomic Line Filtered (RALF) Doppler velocimetry apparatus, along with unanticipated oscillatory signals due to coherent optical transients generated within pure Rb vapor cells. RALF is a high-velocity and high-acceleration extension of the well-known Doppler Global Velocimetry (DGV) technique for constructing multi-dimensional flow velocity vector maps in aerodynamics experiments [H. Komine, U.S. Patent No. 4,919,536 (24 April 1990)]. RALF exploits the frequency dependence of pressure-broadened Rb atom optical absorptions in a heated Rb/N{sub 2} gas cell to encode the Doppler shift of reflected near-resonant (λ{sub 0} ≈ 780.24 nm) laser light onto the intensity transmitted by the cell. The present RALF apparatus combines fiber optic and free-space components and was built to determine suitable operating conditions and performance parameters for the Rb/N{sub 2} gas cells. It yields single-spot velocities of thin laser-driven-flyer test surfaces and incorporates a simultaneous Photonic Doppler Velocimetry (PDV) channel [Strand et al., Rev. Sci. Instrum. 77, 083108 (2006)] for validation of the RALF results, which we demonstrate here over the v = 0 to 1 km/s range. Both RALF and DGV presume the vapor cells to be simple Beer's Law optical absorbers, so we were quite surprised to observe oscillatory signals in experiments employing low pressure pure Rb vapor cells. We interpret these oscillations as interference between the Doppler shifted reflected light and the Free Induction Decay (FID) coherent optical transient produced within the pure Rb cells at the original laser frequency; this is confirmed by direct comparison of the PDV and FID signals. We attribute the different behaviors of the Rb/N{sub 2} vs. Rb gas cells to efficient dephasing of the atomic/optical coherences by Rb-N{sub 2} collisions. The minimum necessary N{sub 2} buffer gas density ≈0.3 amagat translates into a

  19. Tumor vascularity evaluated by transrectal color Doppler US in predicting therapy outcome for low-lying rectal cancer

    International Nuclear Information System (INIS)

    Barbaro, Brunella; Valentini, Vincenzo; Coco, Claudio; Mancini, Anna Paola; Gambacorta, Maria Antonietta; Vecchio, Fabio Maria; Bonomo, Lorenzo

    2005-01-01

    Purpose: To evaluate the impact on T downstaging of the vasculature supplying blood flow to rectal cancer evaluated by color Doppler ultrasound. Methods and Materials: Color Doppler images were graded in 29 T3-staged rectal carcinoma patients sonographically just before chemoradiation. Any arterial vessels detected in rectal masses were assigned one of two grades: vascularity was considered as grade 1 for vessels feeding the periphery and as grade 2 for vessels coursing in all rectal masses within its peripheral and central portions. The pulsatility indices (PI = peak systolic velocity - end-diastolic velocity/time-averaged maximum velocity) were calculated in the central and peripheral portions. Results: The pathologic observations showed a change in stage in 15 of the 23 patients graded 2, positive predictive value 65.2% (p = 0.047), and in one of the six rectal cancers graded 1 (negative predictive value, 83.3%). The minimal peripheral PI values in rectal cancer graded 2 were higher in nonresponding (2.2 ± 1.3) than in responding lesions (1.6 ± 0.7) p = 0.01. Conclusion: Vascularity graded 2 associated with low peripheral PI values are indicators of therapy outcome. Vascularity graded 1 and high peripheral PI values in graded 2 have negative predictive value

  20. Value of downstream circulation in renal artery stenosis with arterial hypertension: comparison between color Doppler flow and digital renal angiography in 123 patients

    International Nuclear Information System (INIS)

    Grataloup, C.; Challande, P.; Plainfosse, M.C.; Girerd, X.; Belattar, K.; Plouin, P.F.

    1996-01-01

    Digital renal angiography and color Doppler flow were compared for diagnosis of renal artery stenosis in 123 hypertensive patients with a prevalence of renal artery stenosis ≥75% of 21 %. Only color Doppler flow signs found downstream from the stenosis could be quantified. A rising time (RT) >0.07 s was the best marker for renal artery stenosis ≥ 75 % according to a receiver operating characteristic curve with a specificity of 97 %, a sensitivity of 88 %, a positive predictive value of 86 %, a negative predictive value of 98 % and an accuracy of 96 %. Digital renal angiography and color Doppler flow findings for renal artery lesions were classified into 4 degrees with agreement for 86 % of the kidneys. (authors). 13 refs., 5 figs., 8 tabs

  1. A flexible optically re-writable color liquid crystal display

    Science.gov (United States)

    Zhang, Yihong; Sun, Jiatong; Liu, Yang; Shang, Jianhua; Liu, Hao; Liu, Huashan; Gong, Xiaohui; Chigrinov, Vladimir; Kowk, Hoi Sing

    2018-03-01

    It is very difficult to make a liquid crystal display (LCD) that is flexible. However, for an optically re-writable LCD (ORWLCD), only the spacers and the substrates need to be flexible because the driving unit and the display unit are separate and there are no electronics in the display part of ORWLCD. In this paper, three flexible-spacer methods are proposed to achieve this goal. A cholesteric liquid crystal colored mirror with a polarizer behind it is used as the colored reflective backboard of an ORWLCD. Polyethersulfone substrates and flexible spacers are used to make the optically re-writable cell insensitive to mechanical force.

  2. The Diagnostic Value of Transvaginal Sonograph (TVS), Color Doppler, and Serum Tumor Marker CA125, CEA, and AFP in Ovarian Cancer.

    Science.gov (United States)

    Zhang, Fang; Zhang, Zhou-Long

    2015-06-01

    The purpose of this study is to investigate the diagnostic value of transvaginal sonograph (TVS), color Doppler, and serum tumor marker CA125, CEA, and AFP in ovarian cancer. From June, 2011 to May, 2013, 102 cases with adnexal mass were recruited in this study (32 cases of malignant ovarian cancer and 70 cases of benign ovarian tumor according to pathological diagnosis). TVS, color Doppler, and serum tumor markers were used for tumor diagnosis. The sensitivity, specifity, positive prediction, negative prediction, and Youden's index were analyzed. Of the 102 patients, 32 were diagnosed with malignant ovarian cancer and 70 were diagnosed with benign ovarian tumor according to pathological diagnosis. Based on TVS results, 37 cases were malignant while 65 cases were benign. Based on color Doppler results, 34 cases were malignant while 68 cases were benign. Based on TVS and color Doppler results, 35 cases were malignant while 65 were benign. Based on CA125 test results, 34 cases were malignant while 68 cases were benign. Based on CEA test results, 8 cases were malignant and 94 cases were benign. Bases on AFP test results, 9 cases were malignant while 93 cases were benign. Based on the results of combination tumor marker test, 38 cases were malignant while 64 cases were benign. The combination of TVS, color Doppler, and tumor marker test showed optimal diagnostic value with a sensitivity of 90.63 %, specificity of 97.14 %, positive prediction of 93.94 %, negative prediction of 98.55 %, and Youden's index of 94.02 %. The combination of TVS, color Doppler, and tumor marker test is of great diagnostic value, which should be widely used in clinical practice.

  3. Iterative inversion of phase-Doppler-anemometry size distributions from sprays of optically inhomogeneous liquids.

    Science.gov (United States)

    Köser, O; Wriedt, T

    1996-05-20

    Using phase Doppler anemometry (PDA) to investigate sprays of optically inhomogeneous liquids leads to blurred measured size distributions. The blurring function is formed by performance of PDA measurements on single-size droplets generated by a piezoelectric droplet generator. To obtain the undistorted droplet-size distributions, a constrained iterative inversion algorithm is applied. The number of iteration steps to achieve the best possible restoration is determined by the use of synthetically generated data that has noise properties similar to the measured histograms. The obtained size distributions are checked by comparison with undistorted measurement results of an atomized optical homogeneous liquid.

  4. A colorful approach to teaching optics

    Science.gov (United States)

    Magnani, Nancy J.; Donnelly, Judith

    2014-09-01

    In a traditional Connecticut elementary school setting, the classroom teacher will teach language arts, social studies and science curriculum. For 5th grade, the science curriculum includes learning about the senses and moon phases, in addition to the fundamentals of light. For art, music and physical education, students are sent to teachers who have certifications in teaching these subjects. In support of the science curriculum, we have traditionally provided workshops to enhance and supplement existing science curriculum. This method of instruction has become a routine. What if we invigorate the curriculum by using visual art to teach science? Will the students achieve a greater understanding of the principals of light? In this paper, we will explore the use of art to enhance the understanding of color and light phenomena.

  5. Optical properties of implanted Xe color centers in diamond

    Science.gov (United States)

    Sandstrom, Russell; Ke, Li; Martin, Aiden; Wang, Ziyu; Kianinia, Mehran; Green, Ben; Gao, Wei-bo; Aharonovich, Igor

    2018-03-01

    Optical properties of color centers in diamond have been the subject of intense research due to their promising applications in quantum photonics. In this work we study the optical properties of Xe related color centers implanted into nitrogen rich (type IIA) and an ultrapure, electronic grade diamond. The Xe defect has two zero phonon lines at ∼794 nm and 811 nm, which can be effectively excited using both green and red excitation, however, its emission in the nitrogen rich diamond is brighter. Near resonant excitation is performed at cryogenic temperatures and luminescence is probed under strong magnetic field. Our results are important towards the understanding of the Xe related defect and other near infrared color centers in diamond.

  6. Optical characteristics of modified fiber tips in single fiber, laser Doppler flowmetry

    Science.gov (United States)

    Oberg, P. Ake; Cai, Hongming; Rohman, Hakan; Larsson, Sven-Erik

    1994-02-01

    Percutaneous laser Doppler flowmetry (LDF) and bipolar surface electromyography (EMG) were used simultaneously for measurement of skeletal muscle (trapezius) perfusion in relation to static load and fatigue. On-line computer (386 SX) processing of the LDF- and EMG- signals made possible interpretation of the relationship between the perfusion and the activity of the muscle. The single fiber laser Doppler technique was used in order to minimize the trauma. A ray-tracing program was developed in the C language by which the optical properties of the fiber and fiber ends could be simulated. Isoirradiance graphs were calculated for three fiber end types and the radiance characteristics were measured for each fiber end. The three types of fiber-tips were evaluated and compared in flow model measurements.

  7. Diagnostic value of color doppler ultrasonography in detecting stenosis and occlusion of central veins in patients with chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Masoud Pezeshki Rad

    2015-01-01

    Full Text Available Venography is an invasive diagnostic test that uses contrast material that provides a picture of the condition of the veins. But, complications, including adverse effects on the kidney, do occur. On the other hand, with the current technological development, application of ultrasound in the diagnosis of obstructive diseases of the veins is gaining popularity, being non-invasive, easy to perform and cost-effective. The aim of this study was to evaluate the diagnostic value of Doppler sonography in the diagnosis of central vein stenosis. In this descriptive-analytical study, 41 hemodialysis patients who had been referred for 50 upper limb venographies to the radiology department of Imam Reza (AS were included. Patients with chronic kidney disease with a history of catheterization of the vein, jugular or subclavian, and who had established fistulas or synthetic vascular grafts were targeted. Central venous ultrasound was performed on both sides to evaluate stenosis or occlusion. Venography was performed by the radiologist the next day or the day before hemodialysis. Data on demographic characteristics, findings of clinical examination and findings of ultrasound as well as venography were recorded by using the SPSS software, Chi-square test and Spearman correlation, and Kappa agreement was calculated for sensitivity, specificity and predictive values. Twenty-three (56% patients were male subjects and 18 patients (44% were female. Twenty-three (56% patients of the study population were aged 60 years. The overall sensitivity, specificity and positive predictive value and negative predictive value of Doppler sonography in the proximal veins in hemodialysis patients compared with venography were, respectively, 80.9%, 79.3%, 73.9% and 85.1%. Color Doppler sonography, as a non-invasive method, could be a good alternative for venography in the assessment of the upper limb with central vein stenosis and occlusion.

  8. Diagnostic value of color doppler ultrasonography in detecting stenosis and occlusion of central veins in patients with chronic kidney disease.

    Science.gov (United States)

    Rad, Masoud Pezeshki; Kazemzadeh, Gholam Hosain; Ziaee, Masood; Azarkar, Ghodsieh

    2015-03-01

    Venography is an invasive diagnostic test that uses contrast material that provides a picture of the condition of the veins. But, complications, including adverse effects on the kidney, do occur. On the other hand, with the current technological development, application of ultrasound in the diagnosis of obstructive diseases of the veins is gaining popularity, being non-invasive, easy to perform and cost-effective. The aim of this study was to evaluate the diagnostic value of Doppler sonography in the diagnosis of central vein stenosis. In this descriptive-analytical study, 41 hemodialysis patients who had been referred for 50 upper limb venographies to the radiology department of Imam Reza (AS) were included. Patients with chronic kidney disease with a history of catheterization of the vein, jugular or subclavian, and who had established fistulas or synthetic vascular grafts were targeted. Central venous ultrasound was performed on both sides to evaluate stenosis or occlusion. Venography was performed by the radiologist the next day or the day before hemodialysis. Data on demographic characteristics, findings of clinical examination and findings of ultrasound as well as venography were recorded by using the SPSS software, Chi-square test and Spearman correlation, and Kappa agreement was calculated for sensitivity, specificity and predictive values. Twenty-three (56%) patients were male subjects and 18 patients (44%) were female. Twenty-three (56%) patients of the study population were aged 60 years. The overall sensitivity, specificity and positive predictive value and negative predictive value of Doppler sonography in the proximal veins in hemodialysis patients compared with venography were, respectively, 80.9%, 79.3%, 73.9% and 85.1%. Color Doppler sonography, as a non-invasive method, could be a good alternative for venography in the assessment of the upper limb with central vein stenosis and occlusion.

  9. Determination of testicular blood flow in camelids using vascular casting and color pulsed-wave Doppler ultrasonography.

    Science.gov (United States)

    Kutzler, Michelle; Tyson, Reid; Grimes, Monica; Timm, Karen

    2011-01-01

    We describe the vasculature of the camelid testis using plastic casting. We also use color pulsed-wave Doppler ultrasonography to measure testicular blood flow and compare the differences between testicular blood flow in fertile and infertile camelids. The testicular artery originates from the ventral surface of the aorta, gives rise to an epididymal branch, and becomes very tortuous as it approaches the testis. Within the supratesticular arteries, peak systolic velocity (PSV) was higher in fertile males compared to infertile males (P = 0.0004). In addition, end diastolic velocity (EDV) within the supratesticular arteries was higher for fertile males when compared to infertile males (P = 0.0325). Within the marginal arteries, PSV was also higher in fertile males compared to infertile males (P = 0.0104). However, EDV within the marginal arteries was not significantly different between fertile and infertile males (P = 0.121). In addition, the resistance index was not significantly different between fertile and infertile males within the supratesticular (P = 0.486) and marginal arteries (P = 0.144). The significance of this research is that in addition to information obtained from a complete reproductive evaluation, a male camelid's fertility can be determined using testicular blood flow measured by Doppler ultrasonography.

  10. Determination of Testicular Blood Flow in Camelids Using Vascular Casting and Color Pulsed-Wave Doppler Ultrasonography

    Directory of Open Access Journals (Sweden)

    Michelle Kutzler

    2011-01-01

    Full Text Available We describe the vasculature of the camelid testis using plastic casting. We also use color pulsed-wave Doppler ultrasonography to measure testicular blood flow and compare the differences between testicular blood flow in fertile and infertile camelids. The testicular artery originates from the ventral surface of the aorta, gives rise to an epididymal branch, and becomes very tortuous as it approaches the testis. Within the supratesticular arteries, peak systolic velocity (PSV was higher in fertile males compared to infertile males (P=0.0004. In addition, end diastolic velocity (EDV within the supratesticular arteries was higher for fertile males when compared to infertile males (P=0.0325. Within the marginal arteries, PSV was also higher in fertile males compared to infertile males (P=0.0104. However, EDV within the marginal arteries was not significantly different between fertile and infertile males (P=0.121. In addition, the resistance index was not significantly different between fertile and infertile males within the supratesticular (P=0.486 and marginal arteries (P=0.144. The significance of this research is that in addition to information obtained from a complete reproductive evaluation, a male camelid's fertility can be determined using testicular blood flow measured by Doppler ultrasonography.

  11. Standardization of the first-trimester fetal cardiac examination using spatiotemporal image correlation with tomographic ultrasound and color Doppler imaging.

    Science.gov (United States)

    Turan, S; Turan, O M; Ty-Torredes, K; Harman, C R; Baschat, A A

    2009-06-01

    The challenges of the first-trimester examination of the fetal heart may in part be overcome by technical advances in three-dimensional (3D) ultrasound techniques. Our aim was to standardize the first-trimester 3D imaging approach to the cardiac examination to provide the most consistent and accurate display of anatomy. Low-risk women with normal findings on first-trimester screening at 11 to 13 + 6 weeks had cardiac ultrasound using the following sequence: (1) identification of the four-chamber view; (2) four-dimensional (4D) volume acquisition with spatiotemporal image correlation (STIC) and color Doppler imaging (angle = 20 degrees, sweep 10 s); (3) offline, tomographic ultrasound imaging (TUI) analysis with standardized starting plane (four-chamber view), slice number and thickness; (4) assessment of fetal cardiac anatomy (four-chamber view, cardiac axis, size and symmetry, atrioventricular valves, great arteries and descending aorta) with and without color Doppler. 107 consecutive women (age, 16-42 years, body mass index 17.2-50.2 kg/m(2)) were studied. A minimum of three 3D volumes were obtained for each patient, transabdominally in 91.6%. Fetal motion artifact required acquisition of more than three volumes in 20%. The median time for TUI offline analysis was 100 (range, 60-240) s. Individual anatomic landmarks were identified in 89.7-99.1%. Visualization of all structures in one panel was observed in 91 patients (85%). Starting from a simple two-dimensional cardiac landmark-the four-chamber view-the standardized STIC-TUI technique enables detailed segmental cardiac evaluation of the normal fetal heart in the first trimester. (c) 2009 ISUOG.

  12. Diagnosis of Pentalogy of Cantrell in the First Trimester Using Transvaginal Sonography and Color Doppler

    Directory of Open Access Journals (Sweden)

    Ayşe Figen Türkçapar

    2015-01-01

    Full Text Available We report the prenatal diagnosis of Cantrell syndrome in the first trimester. During a routine transabdominal ultrasonographic examination, a midline supraumbilical abdominal wall defect including herniated liver and ectopia cordis with a large omphalocele containing the intestines and cystic hygroma was incidentally identified at the 12th week of gestation. A transvaginal sonography examination revealed a severe lumbosacral scoliosis in addition to the inability to visualize the abdominal aorta which was indicative of a severe intracardiac defect. The parents opted for pregnancy to be terminated. In this case report, we discuss the complementary role of transvaginal sonography and Doppler imaging in the diagnosis of Cantrell syndrome in early pregnancy.

  13. Comparative study of multi-slice spiral CT angiography and color doppler ultrasound in diagnosis of arteriosclerotic occlusive disease of lower extremity

    International Nuclear Information System (INIS)

    Li Wanjun; Lai Zhenhui; Cui Dong; Lin Xiupeng; Du Muxuan

    2010-01-01

    Objective: To compare the difference between multi-slice spiral CT angiography (MSCTA) and color doppler ultrasound in diagnosis of arteriosclerotic occlusive disease of lower extremity. Methods: Patients with arteriosclerosis occlusion were assessed by color doppler ultrasound, multi-slice spiral CT angiography and digital subtraction angiography (DSA). The image information of color doppler ultrasound and MSCTA were compared with that of DSA. Results: Color doppler ultrasound showed the anatomical shape and hemodynamics of the arteries of lower extremity. The sensitivity, specificity, and accuracy for diagnosis arteriosclerotic occlusive disease of lower extremity were 88.04%, 90.69% and 88.77% respectively. MSCTA showed the three dimensional structure of the arteries of lower extremity as well as the collateral arteries and the distal arterials. The sensitivity, specificity and accuracy of MSCTA were 97.69%, 96.90% and 97.66%, respectively. Conclusion: Multi-slice spiral CT angiography is an ideal imaging method for the diagnosis of arteriosclerotic occlusive disease of lower extremity. (authors)

  14. Usefulness of hemodynamically distribution of intranodal vessels in differentiating metastatic neck lymph nodes-value of color doppler and spectral wave sonogram

    International Nuclear Information System (INIS)

    Mumtaz, U.

    2017-01-01

    Objective: To evaluate the diagnostic assessment of enlarged lymph nodes, based on its perfusion pattern by taking tissue diagnosis as gold standard. Study Design: Analytical study. Place and Duration of Study: Departments of Radiology and Pathology, PIMS Hospital, Islamabad, from February to May 2016. Methodology: Color sonography of patients with clinically, palpable cervical lymph nodes were carried by senior trainee under the supervision of senior radiologist. Ultrasound guided tissue diagnosis was obtained in all suspected malignant cases. Histopathology was taken as the gold standard for determining accuracy. Results: Accuracy, sensitivity and specificity, positive and negative predictive values of color Doppler ultrasound in detecting malignant cervical lymphadenopathy was found to be 88.46%, 86.05%, 79.31% and 92.50%, respectively with diagnostic accuracy of 86.95%, when intranodal vascular pattern on color Doppler imaging was analyzed. Using spectral wave indexes, the same values were 92.31%, 90.70%, 85.71%, 95.12%, respectively with overall diagnostic accuracy of 91.30%. Conclusion: Color Doppler sonography is much sensitive borderline than grey scale findings alone. Furthermore, lymph nodes appearing in the detection of malignant nodes on grey scale images can be reliably diagnosed on Doppler scan. (author)

  15. Ratio of left ventricular peak E-wave velocity to flow propagation velocity assessed by color M-mode Doppler echocardiography in first myocardial infarction

    DEFF Research Database (Denmark)

    Møller, J E; Søndergaard, E; Seward, J B

    2000-01-01

    OBJECTIVES: To determine the ability of the ratio of peak E-wave velocity to flow propagation velocity (E/Vp) measured with color M-mode Doppler echocardiography to predict in-hospital heart failure and cardiac mortality in an unselected consecutive population with first myocardial infarction (MI...

  16. Sub-Doppler temperature measurements of laser-cooled atoms using optical nanofibres

    International Nuclear Information System (INIS)

    Russell, Laura; Daly, Mark J; Chormaic, Síle Nic; Deasy, Kieran; Morrissey, Michael J

    2012-01-01

    We present a method for measuring the average temperature of a cloud of cold 85 Rb atoms in a magneto-optical trap using an optical nanofibre. A periodic spatial variation is applied to the magnetic fields generated by the trapping coils and this causes the trap centre to oscillate, which, in turn, causes the cloud of cold atoms to oscillate. The optical nanofibre is used to collect the fluorescence emitted by the cold atoms, and the frequency response between the motion of the centre of the oscillating trap and the cloud of atoms is determined. This allows us to make measurements of cloud temperature both above and below the Doppler limit, thereby paving the way for nanofibres to be integrated with ultracold atoms for hybrid quantum devices

  17. [Parenchymal complications of the transplanted kidney: the role of color-Doppler imaging].

    Science.gov (United States)

    Granata, Antonio; Clementi, Silvia; Clementi, Anna; Di Pietro, Fabio; Scarfia, Viviana R; Insalaco, Monica; Aucella, Filippo; Prencipe, Michele; Fiorini, Fulvio; Sicurezza, Elvia

    2012-01-01

    Kidney transplantation is the treatment of choice for end-stage renal disease, given the better quality of life of transplanted patients when compared to patients on maintenance dialysis. In spite of surgical improvements and new immunosuppressive regimens, part of the transplanted grafts still develop chronic dysfunction. Ultrasonography, both in B-mode and with Doppler ultrasound, is an important diagnostic tool in case of clinical conditions which might impair kidney function. Even though ultrasonography is considered fundamental in the diagnosis of vascular and surgical complications of the transplanted kidney, its role is not fully understood in case of parenchymal complications of the graft. The specificity of Doppler ultrasound is low both in case of acute complications such as acute tubular necrosis, drug toxicity and acute rejection, and in case of chronic conditions such as chronic allograft nephropathy. Single determinations of resistance indices present low diagnostic accuracy, which is higher in case of successive measurements performed during the follow-up of the graft. Modern techniques including tissue pulsatility index, maximal fractional area and contrast-enhanced ultrasound increase the diagnostic power of ultrasonography in case of parenchymal complications of the transplanted kidney.

  18. [Changes of renal blood flow during organ-associated foot reflexology measured by color Doppler sonography].

    Science.gov (United States)

    Sudmeier, I; Bodner, G; Egger, I; Mur, E; Ulmer, H; Herold, M

    1999-06-01

    Using colour Doppler sonography blood flow changes of the right kidney during foot reflexology were determined in a placebo-controlled, double-blind, randomised study. 32 healthy young adults (17 women, 15 men) were randomly assigned to the verum or placebo group. The verum group received foot reflexology at zones corresponding to the right kidney, the placebo group was treated on other foot zones. Before, during and after foot reflexology the blood flow of three vessels of the right kidney was measured using colour Doppler sonography. Systolic peak velocity and end diastolic peak velocity were measured in cm/s, and the resistive index, a parameter of the vascular resistance, was calculated. The resistive index in the verum group showed a highly significant decrease (p foot reflexology. There was no difference between men and women and no difference between smokers and non-smokers. Verum and placebo group significantly differed concerning alterations of the resistive index both between the measuring points before versus during foot reflexology (p = 0.002) and those during versus after foot reflexology (p = 0.031). The significant decrease of the resistive index during foot reflexology in the verum group indicates a decrease of flow resistance in renal vessels and an increase of renal blood flow. These findings support the hypothesis that organ-associated foot reflexology is effective in changing renal blood flow during therapy.

  19. Microvascular anastomosis in rodent model evaluated by Fourier domain Doppler optical coherence tomography

    Science.gov (United States)

    Huang, Yong; Tong, Dedi; Zhu, Shan; Wu, Lehao; Ibrahim, Zuhaib; Lee, WP Andrew; Brandacher, Gerald; Kang, Jin U.

    2014-03-01

    Vascular and microvascular anastomosis are critical components of reconstructive microsurgery, vascular surgery and transplant surgery. Imaging modality that provides immediate, real-time in-depth view and 3D structure and flow information of the surgical site can be a great valuable tool for the surgeon to evaluate surgical outcome following both conventional and innovative anastomosis techniques, thus potentially increase the surgical success rate. Microvascular anastomosis for vessels with outer diameter smaller than 1.0 mm is extremely challenging and effective evaluation of the outcome is very difficult if not impossible using computed tomography (CT) angiograms, magnetic resonance (MR) angiograms and ultrasound Doppler. Optical coherence tomography (OCT) is a non-invasive high-resolution (micron level), high-speed, 3D imaging modality that has been adopted widely in biomedical and clinical applications. Phaseresolved Doppler OCT that explores the phase information of OCT signals has been shown to be capable of characterizing dynamic blood flow clinically. In this work, we explore the capability of Fourier domain Doppler OCT as an evaluation tool to detect commonly encountered post-operative complications that will cause surgical failure and to confirm positive result with surgeon's observation. Both suture and cuff based techniques were evaluated on the femoral artery and vein in the rodent model.

  20. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length

    International Nuclear Information System (INIS)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu; Jiao, Shuliang; Zhang, Hao F.

    2015-01-01

    Purpose: Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. Methods: The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. Results: In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild-type rats. The authors’ measured flow rates were consistent with results in the literature. Conclusions: By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length

  1. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length.

    Science.gov (United States)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu; Jiao, Shuliang; Zhang, Hao F

    2015-09-01

    Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as -0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31 μl/min among four wild-type rats. The authors' measured flow rates were consistent with results in the literature. By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.

  2. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu [Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Jiao, Shuliang [Department of Biomedical Engineering, Florida International University, Miami, Florida 33174 (United States); Zhang, Hao F., E-mail: hfzhang@northwestern.edu [Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208 and Department of Ophthalmology, Northwestern University, Chicago, Illinois 60611 (United States)

    2015-09-15

    Purpose: Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. Methods: The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. Results: In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild-type rats. The authors’ measured flow rates were consistent with results in the literature. Conclusions: By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.

  3. Mammary blood supply in various diseases as evidenced by color Doppler sonography

    International Nuclear Information System (INIS)

    Kharchenko, V.P.; Rozhkova, N.I.; Zubovskij, G.A.; Medvedeva, N.A.

    1993-01-01

    Color dopplerosonography, traditional sonography, and mammography without contrast staining, as well as physical and pathomorphologic methods were used in examinations of the mammary glands of 76 women aged 18 to 65. Characteristic features of the blood supply to the gland were detected, and differential diagnostic criteria defined on the basis of these findings, to simplify differentiation between malignant and benign nodular formations and the diffuse changes in the mamma

  4. Real-time three-dimensional color Doppler echocardiography for characterizing the spatial velocity distribution and quantifying the peak flow rate in the left ventricular outflow tract

    Science.gov (United States)

    Tsujino, H.; Jones, M.; Shiota, T.; Qin, J. X.; Greenberg, N. L.; Cardon, L. A.; Morehead, A. J.; Zetts, A. D.; Travaglini, A.; Bauer, F.; hide

    2001-01-01

    Quantification of flow with pulsed-wave Doppler assumes a "flat" velocity profile in the left ventricular outflow tract (LVOT), which observation refutes. Recent development of real-time, three-dimensional (3-D) color Doppler allows one to obtain an entire cross-sectional velocity distribution of the LVOT, which is not possible using conventional 2-D echo. In an animal experiment, the cross-sectional color Doppler images of the LVOT at peak systole were derived and digitally transferred to a computer to visualize and quantify spatial velocity distributions and peak flow rates. Markedly skewed profiles, with higher velocities toward the septum, were consistently observed. Reference peak flow rates by electromagnetic flow meter correlated well with 3-D peak flow rates (r = 0.94), but with an anticipated underestimation. Real-time 3-D color Doppler echocardiography was capable of determining cross-sectional velocity distributions and peak flow rates, demonstrating the utility of this new method for better understanding and quantifying blood flow phenomena.

  5. A comparison of cell-free placental messenger ribonucleic acid and color Doppler ultrasound for the prediction of placental invasion in patients with placenta accreta

    OpenAIRE

    Naghshineh, Elham; Khorvash, Elahe; Kamali, Sara

    2015-01-01

    Background: The aim of the present study was to comparison between cell-free placental messenger ribonucleic acid (mRNA) and Doppler ultrasound for the prediction of placental invasion in women with placenta accreta. Materials and Methods: In this cross-sectional study, 50 pregnant women at risk for placenta accreta underwent color Doppler and assessment of cell-free placental mRNA. Real-time reverse-transcription polymerase chain reaction was used for measurement of cell-free placental m...

  6. Congenital arterioportal fistulas: radiological treatment and color Doppler US follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Teplisky, Dario; Tincani, Eliana Uruena; Lipsich, Jose; Sierre, Sergio [Department of Interventional Radiology, Pichincha 1890, Buenos Aires (Argentina)

    2012-11-15

    Congenital intrahepatic arterioportal fistulas (APFs) are a rare cause of portal hypertension in children. Doppler US is a useful diagnostic imaging modality. Transarterial embolization is a minimally invasive and effective therapy allowing occlusion of the fistula and restoration of liver hemodynamics. To describe the clinical and radiologic findings, percutaneous treatment and role of D-US in the postembolization follow-up of children with APF. Between 2002 and 2011, four children with APF were treated. Initial diagnosis and follow-up was performed with D-US and confirmed by arteriography, followed by endovascular embolization in all patients. D-US demonstrated abnormal arterioportal communications in all patients. Six endovascular procedures were performed in these four children. In two children, no residual fistula was seen on D-US after the first procedure and symptoms resolved. In the other two children, D-US demonstrated residual flow through the fistula, with resolution of pathological D-US findings and symptoms after the second endovascular procedure. All four children were successfully treated and asymptomatic at the end of follow-up. The mean follow-up was 24 months. Interventional radiology has a key role in the treatment of congenital APF. D-US is a noninvasive and effective tool for the diagnosis and follow-up of these patients. (orig.)

  7. Renal transplant assessment with color and pulsed Doppler ultrasonography. 2nd part: inmunomedical complications

    International Nuclear Information System (INIS)

    Martin Hervas, C.; Gil de Miguel, A.

    1994-01-01

    We have performed 304 serial explorations in 140 renal transplant (Tx) recipients (42 recent and 98 past patients), assessing the morphological aspect of the graft (Size, surface, thickness and echogenicity of the parenchyma, corticomedullary index and renal sinus index), vascular permeability and the morphology of the arterial and venous waves, with calculation of the resistance indices (RI). We have compared these findings with those observed in a control group of 45 recipients with normally functioning grafts, comparing the different pathologies with respect to analytical, isotopic and histological findings. Doppler is a highly sensitive method for detecting processes that increase parenchymal resistance (rejection, acute tubular necrosis, cyclosporine toxicity, disease recurrence, infection, etc), but its specificity is poor. In past Tx recipients, chronic dysfunction or failure is the principal object of interest, while in the immediate postoperative period, it is important to compare the results of basal and follow-up studies. In acute tubular necrosis, the IR were not seen to deteriorate, in contrast to the findings in acute vascular rejection, and inversion of the diastolic pressures is a sign of poor prognosis. Despite the performance of other tests, biopsy is necessary in many cases to identify the etiology. (Author) 9 refs

  8. Significance of 'Bridging vessel sign' on color Doppler ultrasound in diagnosis of uterine subserosal leiomyoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin Hee; Lee, Jung Hee; Sohn, Chul Ho; Woo, Seung Koo [Keimyung University School of Medicine, Taegu (Korea, Republic of); Kim, Jung Sik [Radiological Clinic, Taegu (Korea, Republic of)

    2002-06-15

    To evaluate the usefulness of the 'bridging vessel sign' in differentiating uterine subserosal leiomyoma from other pelvic masses mimicking leiomyoma on color Doppler ultrasound. Histologically (n=58) and clinically (n=1) proven 59 masses from 55 women were included in this study. Histologic diagnoses included leiomyoma (n=32) and various kinds of other masses (n=27). On gray scale ultrasound, the size of tumor and presence of the ovaries were recorded. On color Doppler ultrasound, the presence of 'bridging vessel sign', which was defined as a linear vessel demonstrated between the mass and the uterus was documented. Uterine subserosal leiomyoma was diagnosed on the basis of finding this sign, and the diagnostic accuracy of this sign in differentiating subserosal leiomyoma from other pelvic tumors was calculated. In addition, the diagnostic accuracy of this sign combined with the visibility of theopsilateral ovary was compared. The size of subserosal leiomyomas ranged from 4.2 to 22.1 cm (mean, 8.3 cm) while the size of other pelvic masses, from 4.6 to 21.5 cm (mean, 9.6 cm). The 'bridging vessel sign' was demonstrated in thirty of 32 leiomyomas and in three of 27 other pelvis masses. The sensitivity, specificity, accuracy, positive predictive value, and negative value of the 'bridging vessel sign' in the diagnosis of subserosal leiomyoma were 93.8%, 99.9%, 91.5%, 90.9% and 92.3%, respectively. The detection of the ipsilateral ovary was possible in 14 of 30 women with leiomyomas and in four of 25 women with other pelvic masses. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of this finding in the diagnosis of subserosal leiomyoma were 46.7%, 84.0%, 63.6%, 77.8%, and 56.8%, respectively. 'Bridging vessel sign' can be an useful finding in the differential diagnosis of subserosal leiomyomas from other pelvic masses mimicking leiomyoma.

  9. Evaluation of portal hypertension in cirrhotic patients using color duplex-doppler ultrasound. Preliminary study; Evaluacion de la hipertension portal del cirrotico mediante ultrasonografia duplex-Doppler color. Estudio prliminar

    Energy Technology Data Exchange (ETDEWEB)

    Varas, M J; Torres, G; Sanllely, H [Unidad de Ecografias, Consorcio del Hospital de la Cruz Roja, L` Hospitalet de Llobregat, Barcelona (Spain)

    1996-09-01

    The objective was to compare data obtained by color duplex-Doppler ultrasound (mean velocity, flow and portal vein congestion index) in patients with chronic diffuse liver disease with and without portal hypertension (PH) (demonstrated endoscopically) with that of a healthy control group. Over a two-year period, 50 studies were performed in 10 healthy subjects (control group) with a mean age of 36 years and in 40 chronic liver disease patients (study group with a mean age of 58 years), most of whom presented alcoholic liver cirrhosis and belonged to Child-Pugh class B. They were subdivided according to endoscopic study into patients without (group 1) and with (group 2) portal hypertension. There were statistically significant differences in the diameters of splenic vein, spleen, portal vein and in the portal Vm, which decreased as the Child-Pugh score rose. When the patients without (group 1) and with (group 2) endoscopic evidence of PH (esophageal varices)were analyzed and compared, the two groups presented no statistically significant differences with respect to portal Vm, blood flow out of the liver, presence of collateral vessels, or the portal vein congestion index; the latter was significantly different in both the study group as a whole and in the patients with PH when compared with the control group. Given that this report is based on a pilot study which requires a larger sample number, we are unable to arrive at definitive conclusions. (Author) 18 refs.

  10. Optical properties of pre-colored dental monolithic zirconia ceramics.

    Science.gov (United States)

    Kim, Hee-Kyung; Kim, Sung-Hun

    2016-12-01

    The purposes of this study were to evaluate the optical properties of recently marketed pre-colored monolithic zirconia ceramics and to compare with those of veneered zirconia and lithium disilicate glass ceramics. Various shades of pre-colored monolithic zirconia, veneered zirconia, and lithium disilicate glass ceramic specimens were tested (17.0×17.0×1.5mm, n=5). CIELab color coordinates were obtained against white, black, and grey backgrounds with a spectrophotometer. Color differences of the specimen pairs were calculated by using the CIEDE2000 (ΔE 00 ) formula. The translucency parameter (TP) was derived from ΔE 00 of the specimen against a white and a black background. X-ray diffraction was used to determine the crystalline phases of monolithic zirconia specimens. Data were analyzed with 1-way ANOVA, Scheffé post hoc, and Pearson correlation testing (α=0.05). For different shades of the same ceramic brand, there were significant differences in L * , a * , b * , and TP values in most ceramic brands. With the same nominal shade (A2), statistically significant differences were observed in L * , a * , b * , and TP values among different ceramic brands and systems (Pceramics of the corresponding nominal shades ranged beyond the acceptability threshold. Due to the high L * values and low a * and b * values, pre-colored monolithic zirconia ceramics can be used with additional staining to match neighboring restorations or natural teeth. Due to their high value and low chroma, unacceptable color mismatch with adjacent ceramic restorations might be expected. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Transvaginal color Doppler imaging of uterine contractions in early pregnancies: Significance of uterine contractions in early pregnancy failure

    International Nuclear Information System (INIS)

    Lee, Eun Ju; Han, Chang Jin; Suh, Jung Ho; Kwon, Hyuck Chan

    1999-01-01

    To assess uterine contractions in early pregnancies using transvaginal color Doppler sonography (TVCDS) and to determine the role of uterine contractions in the diagnosis of early pregnancy failure. 76 patients with abnormal pregnancy diagnosed by sonography or histopathology up to 10 weeks of gestation and 38 normal pregnant women as the control group were examines with TVCDS. The presence of uterine contractions was determined by complete or partial disappearance of the color flow signals of vessels within myometrium, and the direction, amplitude (grade 1-3), and interval of uterine contractions were also evaluated. Uterine contractions were identified in 42 (55.3%) of 76 patients with abnormal pregnancy, whereas they were detected only in 2 (5.3%) of 38 normal pregnant women who had initial grade 1 contraction but disappeared in the follow-up study. In 26 patients with blighted ovum or missed abortion, 15 patients (57.7%),showed uterine contraction of grade 1 in 3 cases, grade 2 in 8 cases, and grade 3 in 4 cases and interval from 45 seconds to 5 minutes. In 30 patients with inevitable or incomplete abortion, 23 patients (76.6%) showed uterine contraction of grade 1 in 2 cases, grade 2 in 9 cases, and grade 3 in 12 cases and interval from 1 to 5 minutes. 4 (20%) of 20 patients with threatened abortion had uterine contraction of grade 2 and interval from 2 to 4 minutes. The presence of uterine contractions was significantly different in abnormal pregnancies compared with that of normal and also among the tree different groups of abnormal pregnancies, but the amplitude did not differ.

  12. Two-dimensional color Doppler echocardiography for left ventricular stroke volume assessment: a comparison study with three-dimensional echocardiography.

    Science.gov (United States)

    Silva, Cristina Da; Pedro, Fátima; Deister, Lizandra; Sahlén, Anders; Manouras, Aristomenis; Shahgaldi, Kambiz

    2012-08-01

    Whether measurement of left ventricular outflow tract diameter (LVOTd) using color Doppler (CD) in order to more accurately define LVOTd is more accurate for determination of stroke volume (SV) than gray scale and compare it with direct measurement of LVOT area (a) using three-dimensional echocardiography (3DE) for SV determination. Twenty-one volunteers were examined. LVOTa was calculated by two-dimensional echocardiography (2DE) using the following formula: π× (d/2)(2) , d = LVOT diameter by gray scale and CD, respectively. Planimetry of LVOTa was performed in parasternal long axis using 3DE. Eccentricity Index was calculated using the lateral and anterior-posterior LVOTd. SV was obtained by four different methods: (1) 2D gray scale, (2) 2D color, (3) LVOTa × LVOT velocity time integral, and (4) SV by Simpson's biplane method. Gray scale LVOTd was significantly smaller compared to LVOTd obtained with CD (P vs 3.67 ± 0.70 cm(2) , P vs 3.61 ± 0.89 cm(2) , P = 0.011). Half of the subjects had at least 17% difference between the lateral and anterior-posterior LVOTd. There were significant differences between SV by 2D gray scale and 2D CD (82.8 ± 17.1 mL vs 92.4 ± 16.8 mL, P vs 90.7 ± 19.8 mL, P = 0.025). Our study demonstrates LVOT being frequently elliptical. SV and LVOTa were found to be similar when comparing 2DE CD and 3DE planimetry and showed higher values in comparison to 2DE gray scale, which suggests 2DE CD to be an alternative approach for SV assessment. © 2012, Wiley Periodicals, Inc.

  13. Transvaginal color Doppler imaging of uterine contractions in early pregnancies: Significance of uterine contractions in early pregnancy failure

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Ju; Han, Chang Jin; Suh, Jung Ho; Kwon, Hyuck Chan [Aju University SChool of Medicine, Suwon (Korea, Republic of)

    1999-06-15

    To assess uterine contractions in early pregnancies using transvaginal color Doppler sonography (TVCDS) and to determine the role of uterine contractions in the diagnosis of early pregnancy failure. 76 patients with abnormal pregnancy diagnosed by sonography or histopathology up to 10 weeks of gestation and 38 normal pregnant women as the control group were examines with TVCDS. The presence of uterine contractions was determined by complete or partial disappearance of the color flow signals of vessels within myometrium, and the direction, amplitude (grade 1-3), and interval of uterine contractions were also evaluated. Uterine contractions were identified in 42 (55.3%) of 76 patients with abnormal pregnancy, whereas they were detected only in 2 (5.3%) of 38 normal pregnant women who had initial grade 1 contraction but disappeared in the follow-up study. In 26 patients with blighted ovum or missed abortion, 15 patients (57.7%),showed uterine contraction of grade 1 in 3 cases, grade 2 in 8 cases, and grade 3 in 4 cases and interval from 45 seconds to 5 minutes. In 30 patients with inevitable or incomplete abortion, 23 patients (76.6%) showed uterine contraction of grade 1 in 2 cases, grade 2 in 9 cases, and grade 3 in 12 cases and interval from 1 to 5 minutes. 4 (20%) of 20 patients with threatened abortion had uterine contraction of grade 2 and interval from 2 to 4 minutes. The presence of uterine contractions was significantly different in abnormal pregnancies compared with that of normal and also among the tree different groups of abnormal pregnancies, but the amplitude did not differ.

  14. Effect of optical pumping on absorption spectra for the doppler broadened rubidium

    International Nuclear Information System (INIS)

    Shin, Seo Ro; Noh, Heung Ryoul

    2008-01-01

    The absorption of a laser beam in the Doppler broadened atomic vapor cell is one of the simplest problems in atomic physics. Although many reports on theoretical and experimental studies of linear absorption have been reported, the effect of optical pumping on the absorption coefficient has not been studied in detail. In this presentation, we present a theoretical and experimental study on linear absorption for the Doppler broadened rubidium vapor cell. The absorption coefficient of a σ"+"(or π)polarized laser beam was calculated as a function of the laser frequency for the various laser intensities. The calculated results were compared with the experimental results. Figure 1(a) shows the calculated absorption coefficient of the π polarized laser beam for the transition F"g"=1→F"e"=0,1,2 of the "87"Rb atom. The diameter of the laser beam was 3mm and the intensity was I=0 and I=0.1I"8"(I"8"=16.2W/m"2"). The peak values for various intensities are shown in Fig. 1(b). We found that the absorption coefficient for the transition from the lower hyperfine state decreased with the increased laser intensity, whereas that for the transition from the upper hyperfine state increased(decreased)for the σ"+"(π)polarized laser beam

  15. A fiber optic Doppler sensor and its application in debonding detection for composite structures.

    Science.gov (United States)

    Li, Fucai; Murayama, Hideaki; Kageyama, Kazuro; Meng, Guang; Ohsawa, Isamu; Shirai, Takehiro

    2010-01-01

    Debonding is one of the most important damage forms in fiber-reinforced composite structures. This work was devoted to the debonding damage detection of lap splice joints in carbon fiber reinforced plastic (CFRP) structures, which is based on guided ultrasonic wave signals captured by using fiber optic Doppler (FOD) sensor with spiral shape. Interferometers based on two types of laser sources, namely the He-Ne laser and the infrared semiconductor laser, are proposed and compared in this study for the purpose of measuring Doppler frequency shift of the FOD sensor. Locations of the FOD sensors are optimized based on mechanical characteristics of lap splice joint. The FOD sensors are subsequently used to detect the guided ultrasonic waves propagating in the CFRP structures. By taking advantage of signal processing approaches, features of the guided wave signals can be revealed. The results demonstrate that debonding in the lap splice joint results in arrival time delay of the first package in the guided wave signals, which can be the characteristic for debonding damage inspection and damage extent estimation.

  16. Value of sonomammography utilizing color Doppler technique in qualification of breast cancer patients for sentinel node identification

    International Nuclear Information System (INIS)

    Basta, P.; Wadowska-Jaszczynska, K.; Krysztopowicz, W.; Przybylska, P.; Wisniowski, Z.

    2007-01-01

    Sentinel node identification has become a standard procedure in the management of breast cancer. This procedure requires involvement of a multidisciplinary team and is rather costly. Ultrasonography (USG) of axillary lymph nodes is a method that gives hope for improving the quality of qualification of patients for the procedure. Eighty patients with grade I and II breast cancers underwent sentinel node identification followed by axillary lymphadenectomy. Pre-operative ultrasonography was employed to assess axillary lymph nodes, using the morphological and vascular characteristics as predictors of the presence of lymph node metastases. Sensitivity of sentinel node identification reached 89.3%, specificity - 100%, positive predictive value - 100%, negative predictive value - 93.5%, percentage of false negative results - 10.7%. Sensitivity of USG reached 68.75 %, and specificity - 70.31%. In the group of patients in whom the sentinel node was identified, the sensitivity of the method was 69.23 %, and specificity - 72.41%. Preoperative axillary lymph node ultrasonography in breast cancer patients, utilizing color Doppler technique, allows better selection of patients for sentinel node identification procedure. (author)

  17. Color M-mode Doppler flow propagation velocity is a preload insensitive index of left ventricular relaxation: animal and human validation.

    Science.gov (United States)

    Garcia, M J; Smedira, N G; Greenberg, N L; Main, M; Firstenberg, M S; Odabashian, J; Thomas, J D

    2000-01-01

    To determine the effect of preload in color M-mode Doppler flow propagation velocity (v(p)). The interpretation of Doppler filling patterns is limited by confounding effects of left ventricular (LV) relaxation and preload. Color M-mode v(p) has been proposed as a new index of LV relaxation. We studied four dogs before and during inferior caval (IVC) occlusion at five different inotropic stages and 14 patients before and during partial cardiopulmonary bypass. Left ventricular (LV) end-diastolic volumes (LV-EDV), the time constant of isovolumic relaxation (tau), left atrial (LA) pre-A and LV end-diastolic pressures (LV-EDP) were measured. Peak velocity during early filling (E) and v(p) were extracted by digital analysis of color M-mode Doppler images. In both animals and humans, LV-EDV and LV-EDP decreased significantly from baseline to IVC occlusion (both p < 0.001). Peak early filling (E) velocity decreased in animals from 56 +/- 21 to 42 +/- 17 cm/s (p < 0.001) without change in v(p) (from 35 +/- 15 to 35 +/- 16, p = 0.99). Results were similar in humans (from 69 +/- 15 to 53 +/- 22 cm/s, p < 0.001, and 37 +/- 12 to 34 +/- 16, p = 0.30). In both species, there was a strong correlation between LV relaxation (tau) and v(p) (r = 0.78, p < 0.001, r = 0.86, p < 0.001). Our results indicate that color M-mode Doppler v(p) is not affected by preload alterations and confirms that LV relaxation is its main physiologic determinant in both animals during varying lusitropic conditions and in humans with heart disease.

  18. The use of the color Doppler ultrasonography in the diagnosis and monitoring of an atypical case of giant-cell arteritis.

    Science.gov (United States)

    Martins, N; Polido-Pereira, J; Rodrigues, A M; Soares, F; Batista, P; Pereira da Silva, J A

    2016-01-01

    Giant Cell Arteritis (GCA) is a large vessels vasculitis that is typically characterised by headache, scalp tenderness, jaw claudication and visual disturbances. Temporal arteries color Doppler ultrasonography (CDUS) is a sensitive and non-invasive image technique used in the diagnosis of this disease. This work highlights the importance of CDUS in the diagnostic workup of GCA and also demonstrates it´s usefullness in the evaluation and documentation of the response to corticosteroids therapy in an atypical case of ACG.

  19. Association of maternal and umbilical cord blood leptin concentrations and abnormal color Doppler indices of umbilical artery with fetal growth restriction

    Directory of Open Access Journals (Sweden)

    Elahe Zareaan

    2017-08-01

    Full Text Available Background: Fetal growth restriction (FGR is a condition with heterogeneous pathophysiology which characterized by fetal weight less than the tenth percentile for gestational age. Several factors have impact on maternal, placental and fetal due to growth restriction. Objective: The aim of this study was to investigate the relationship between levels of leptin in the cord, and serum leptin of mothers also abnormal color Doppler indices of umbilical artery with fetal growth restriction. Materials and Methods: This is a cross sectional study conducted in Isfahan, Iran, 2015-2016. We recruited 40 women with singleton pregnancies complicated by fetal growth restriction (Group I and 40 pregnant women with normal fetal growth (Group II with matched age. Maternal serum and umbilical artery leptin levels were determined with Enzyme-Linked immunosorben method. Also, color Doppler ultrasound of umbilical artery was performed. Results: Mean maternal and fetal leptin levels were lower in the FGR group compared to the normal group (36.58±(20.99 and 7.42 ±(4.08vs. 47.32±(22.50 and 30.49±(14.50 respectively. Also, mean fetal leptin level was lower in the group with abnormal color Doppler sonographic indices compared to the normal group (7. 40 ±(4.10vs 27.06±(15.80, respectively. Conclusion: This study indicated that maternal and fetal leptin levels are correlated with FGR originating from damaged placental function; also fetal leptin level can indicate changes in color Doppler sonographic indices.

  20. Determining degree of optic nerve edema from color fundus photography

    Science.gov (United States)

    Agne, Jason; Wang, Jui-Kai; Kardon, Randy H.; Garvin, Mona K.

    2015-03-01

    Swelling of the optic nerve head (ONH) is subjectively assessed by clinicians using the Frisén scale. It is believed that a direct measurement of the ONH volume would serve as a better representation of the swelling. However, a direct measurement requires optic nerve imaging with spectral domain optical coherence tomography (SD-OCT) and 3D segmentation of the resulting images, which is not always available during clinical evaluation. Furthermore, telemedical imaging of the eye at remote locations is more feasible with non-mydriatic fundus cameras which are less costly than OCT imagers. Therefore, there is a critical need to develop a more quantitative analysis of optic nerve swelling on a continuous scale, similar to SD-OCT. Here, we select features from more commonly available 2D fundus images and use them to predict ONH volume. Twenty-six features were extracted from each of 48 color fundus images. The features include attributes of the blood vessels, optic nerve head, and peripapillary retina areas. These features were used in a regression analysis to predict ONH volume, as computed by a segmentation of the SD-OCT image. The results of the regression analysis yielded a mean square error of 2.43 mm3 and a correlation coefficient between computed and predicted volumes of R = 0:771, which suggests that ONH volume may be predicted from fundus features alone.

  1. Evaluation of a multimode fiber optic low coherence interferometer for path length resolved Doppler measurments of diffuse light

    NARCIS (Netherlands)

    Varghese, Babu; Rajan, Vinayakrishnan; van Leeuwen, Ton; Steenbergen, Wiendelt

    2007-01-01

    The performance of a graded index multimode fiber optic low coherence Mach-Zehnder interferometer with phase modulation is analyzed. Investigated aspects were its ability to measure path length distributions and to perform path length resolved Doppler measurements of multiple scattered photons in a

  2. Evaluation of a multimode fiber optic low coherence interferometer for path length resolved Doppler measurements of diffuse light

    NARCIS (Netherlands)

    Varghese, Babu; Rajan, Vinayakrishnan; van Leeuwen, Ton G.; Steenbergen, Wiendelt

    2007-01-01

    The performance of a graded index multimode fiber optic low coherence Mach-Zehnder interferometer with phase modulation is analyzed. Investigated aspects were its ability to measure path length distributions and to perform path length resolved Doppler measurements of multiple scattered photons in a

  3. Identificação pelo eco-Doppler colorido de fístula arteriovenosa na trombose venosa profunda Arteriovenous fistula in deep venous thrombosis identified by color-flow Doppler ultrasonography

    Directory of Open Access Journals (Sweden)

    Fanilda Souto Barros

    2006-09-01

    Full Text Available Os três casos são referentes a pacientes em tratamento para trombose venosa profunda encaminhados ao laboratório vascular para avaliação da recanalização e/ou progressão do processo trombótico. Durante o estudo pelo eco-Doppler colorido, foram identificados sinais ecográficos compatíveis com fístula arteriovenosa no interior do trombo e adjacente à parede venosa.We report on a case series of three patients undergoing treatment for deep venous thrombosis, referred to our vascular laboratory for evaluation of recanalization and/or progression of the thrombotic process. During the color-flow Doppler ultrasonography, we identified ultrasound signs typical of arteriovenous fistula flow pattern within the thrombus and adjacent to the venous wall.

  4. Real Time Decoding of Color Symbol for Optical Positioning System

    Directory of Open Access Journals (Sweden)

    Abdul Waheed Malik

    2015-01-01

    Full Text Available This paper presents the design and real-time decoding of a color symbol that can be used as a reference marker for optical navigation. The designed symbol has a circular shape and is printed on paper using two distinct colors. This pair of colors is selected based on the highest achievable signal to noise ratio. The symbol is designed to carry eight bit information. Real time decoding of this symbol is performed using a heterogeneous combination of Field Programmable Gate Array (FPGA and a microcontroller. An image sensor having a resolution of 1600 by 1200 pixels is used to capture images of symbols in complex backgrounds. Dynamic image segmentation, component labeling and feature extraction was performed on the FPGA. The region of interest was further computed from the extracted features. Feature data belonging to the symbol was sent from the FPGA to the microcontroller. Image processing tasks are partitioned between the FPGA and microcontroller based on data intensity. Experiments were performed to verify the rotational independence of the symbols. The maximum distance between camera and symbol allowing for correct detection and decoding was analyzed. Experiments were also performed to analyze the number of generated image components and sub-pixel precision versus different light sources and intensities. The proposed hardware architecture can process up to 55 frames per second for accurate detection and decoding of symbols at two Megapixels resolution. The power consumption of the complete system is 342mw.

  5. Role of color Doppler US in the evaluation of uterine leiomyoma treated with gonadotrophin-releasing hormone (GnRH) agonist (Zoladex)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Sik; Sohn, Cheol Ho; Lee, Tae Sung [Keimyung University Dongsan Medical Center, Taegu (Korea, Republic of)

    1999-03-15

    To access the role of color Doppler US in the evaluation of uterine leiomyoma treated with GnRH agonist (Zoladex). Out of 25 patients with uterine leiomyoma treated with Zoladex, nineteen cases of leiomyoma in 18 women who had US examination before and after medication were included in this study. Zoladex was injected subcutaneously three times within three months. Both gray scale and color Doppler US were obtained before and 1-3 months after the medication. The size, volume, location and internal echoes of the leiomyoma were recorded with gray scale US. Changes in the amount of color signal within leiomyomas were recorded. Pulsatility index (PI), resistive index (RI), peak systolic velocity (PSV) of both uterine artery and arteries within leiomyomas were also recorded. The image findings of good response group and poor response group in which the volume reduction of the leiomyoma was above or below 50% respectively were compared with each other. The reduction of the volume of leiomyoma was compared between a group with decrease in the amount of color signals during follow-up US and a group with increase or no change. Mean reduction of the volume of leiomyomas was 52%. Changes in the amount of color signals of the leiomyoma, PI, RI, PSV obtained from the arteries within leiomyomas were not correlated with the change of the volume of leiomyomas. PSV of uterine artery in one month follow-up and PI of two month follow-up were correlated with the changes of the volume of leiomyomas (p<0.05). RI of uterine artery in two month follow-up was useful in prediction of the good response group and the poor response group (p<0.05). The prediction of the volume reduction of leiomyoma following Zoladex medication might be possible by obtaining RI of uterine artery in two month follow-up. Doppler US of the arteries within the leiomyoma was not useful.

  6. Role of color Doppler US in the evaluation of uterine leiomyoma treated with gonadotrophin-releasing hormone (GnRH) agonist (Zoladex)

    International Nuclear Information System (INIS)

    Kim, Jung Sik; Sohn, Cheol Ho; Lee, Tae Sung

    1999-01-01

    To access the role of color Doppler US in the evaluation of uterine leiomyoma treated with GnRH agonist (Zoladex). Out of 25 patients with uterine leiomyoma treated with Zoladex, nineteen cases of leiomyoma in 18 women who had US examination before and after medication were included in this study. Zoladex was injected subcutaneously three times within three months. Both gray scale and color Doppler US were obtained before and 1-3 months after the medication. The size, volume, location and internal echoes of the leiomyoma were recorded with gray scale US. Changes in the amount of color signal within leiomyomas were recorded. Pulsatility index (PI), resistive index (RI), peak systolic velocity (PSV) of both uterine artery and arteries within leiomyomas were also recorded. The image findings of good response group and poor response group in which the volume reduction of the leiomyoma was above or below 50% respectively were compared with each other. The reduction of the volume of leiomyoma was compared between a group with decrease in the amount of color signals during follow-up US and a group with increase or no change. Mean reduction of the volume of leiomyomas was 52%. Changes in the amount of color signals of the leiomyoma, PI, RI, PSV obtained from the arteries within leiomyomas were not correlated with the change of the volume of leiomyomas. PSV of uterine artery in one month follow-up and PI of two month follow-up were correlated with the changes of the volume of leiomyomas (p<0.05). RI of uterine artery in two month follow-up was useful in prediction of the good response group and the poor response group (p<0.05). The prediction of the volume reduction of leiomyoma following Zoladex medication might be possible by obtaining RI of uterine artery in two month follow-up. Doppler US of the arteries within the leiomyoma was not useful.

  7. Broader color gamut of color-modulating optical coating display based on indium tin oxide and phase change materials.

    Science.gov (United States)

    Ni, Zhigang; Mou, Shenghong; Zhou, Tong; Cheng, Zhiyuan

    2018-05-01

    A color-modulating optical coating display based on phase change materials (PCM) and indium tin oxide (ITO) is fabricated and analyzed. We demonstrate that altering the thickness of top-ITO in this PCM-based display device can effectively change color. The significant role of the top-ITO layer in the thin-film interference in this multilayer system is confirmed by experiment as well as simulation. The ternary-color modulation of devices with only 5 nano thin layer of phase change material is achieved. Furthermore, simulation work demonstrates that a stirringly broader color gamut can be obtained by introducing the control of the top-ITO thickness.

  8. Interrelation of surface tension, optical turbidity, and color of operational transformer oils

    International Nuclear Information System (INIS)

    L’vov, S. Yu.; Lyut’ko, E. O.; Lankau, Ya. V.; Komarov, V. B.; Seliverstov, A. F.; Bondareva, V. N.; L’vov, Yu. N.; L’vov, M. Yu.; Ershov, B. G.

    2011-01-01

    Measurements of the acidity, optical turbidity, surface tension, and color of transformer oil from 54 power transformers, autotransformers, and shunt reactors are reported. Changes in surface tension, optical turbidity, and color are found to obey adequate linear correlations, while the acidity has no correlation with any of these properties. Numerical criteria for the maximum permissible state (quality) of the oil with respect to optical turbidity and color are obtained. Recommendations to operating staff are provided for cases in which the criteria for optical turbidity and color are exceeded.

  9. Value of sagittal color Doppler ultrasonography as a supplementary tool in the differential diagnosis of fetal cleft lip and palate

    International Nuclear Information System (INIS)

    Lee, Myoung Seok; Cho, Jeong Yeon; Kim, Sang Youn; Kim, Seung Hyup; Park, Joong Shin; Jun, Jong Kwan

    2017-01-01

    The purpose of this study was to evaluate the feasibility and usefulness of sagittal color Doppler ultrasonography (CDUS) for the diagnosis of fetal cleft lip (CL) and cleft palate (CP). We performed targeted ultrasonography on 25 fetuses with CL and CP, taking coronal and axial images of the upper lip and maxillary alveolar arch in each case. The existence of defects in and malalignment of the alveolus on the axial image, hard palate defects on the midsagittal image, and flow-through defects on CDUS taken during fetal breathing or swallowing were assessed. We compared the ultrasonography findings with postnatal findings in all fetuses. Alveolar defects were detected in 16 out of 17 cases with CP and four out of eight cases with CL. Alveolar malalignment and hard palate defects were detected in 11 out of 17 cases and 14 out of 17 cases with CP, respectively, but not detected in any cases with CL. Communicating flow through the palate defect was detected in 11 out of 17 cases of CL with CP. The accuracy of detection in axial scans of an alveolar defect and malalignment was 80% and 76%, respectively. Accuracy of detection of in mid-sagittal images of hard palate defect and flow was 80% and 86%, respectively. The overall diagnostic accuracy of combined axial and sagittal images with sagittal CDUS was 92%. Sagittal CDUS of the fetal hard palate is a feasible method to directly reveal hard palate bony defects and flow through defects, which may have additional value in the differential diagnosis of fetal CL and CP

  10. Value of sagittal color Doppler ultrasonography as a supplementary tool in the differential diagnosis of fetal cleft lip and palate

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myoung Seok [Dept. of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Cho, Jeong Yeon; Kim, Sang Youn; Kim, Seung Hyup [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Park, Joong Shin; Jun, Jong Kwan [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    2017-01-15

    The purpose of this study was to evaluate the feasibility and usefulness of sagittal color Doppler ultrasonography (CDUS) for the diagnosis of fetal cleft lip (CL) and cleft palate (CP). We performed targeted ultrasonography on 25 fetuses with CL and CP, taking coronal and axial images of the upper lip and maxillary alveolar arch in each case. The existence of defects in and malalignment of the alveolus on the axial image, hard palate defects on the midsagittal image, and flow-through defects on CDUS taken during fetal breathing or swallowing were assessed. We compared the ultrasonography findings with postnatal findings in all fetuses. Alveolar defects were detected in 16 out of 17 cases with CP and four out of eight cases with CL. Alveolar malalignment and hard palate defects were detected in 11 out of 17 cases and 14 out of 17 cases with CP, respectively, but not detected in any cases with CL. Communicating flow through the palate defect was detected in 11 out of 17 cases of CL with CP. The accuracy of detection in axial scans of an alveolar defect and malalignment was 80% and 76%, respectively. Accuracy of detection of in mid-sagittal images of hard palate defect and flow was 80% and 86%, respectively. The overall diagnostic accuracy of combined axial and sagittal images with sagittal CDUS was 92%. Sagittal CDUS of the fetal hard palate is a feasible method to directly reveal hard palate bony defects and flow through defects, which may have additional value in the differential diagnosis of fetal CL and CP.

  11. Study on the value of color Doppler ultrasound in evaluating the efficacy of neoadjuvant chemotherapy for breast cancer

    Directory of Open Access Journals (Sweden)

    Chao-Xi Li

    2016-05-01

    Full Text Available Objective: To explore the value of color Doppler flow imaging (CDFI in evaluating the efficacy of neoadjuvant chemotherapy (NCT for breast cancer. Methods: A total of 60 patients with breast cancer who were admitted in our hospital from January, 2015 to December, 2015 were included in the study. TC scheme was used for chemotherapy before operation, i.e. cyclophosphamide 600 mg/m2, docetaxel 75 mg/m2, IV. Three-week treatment was regarded as one course, for 2-4 weeks. After chemotherapy for 1-2 week, the operation was performed. CDFI was used to observe the lesion location, number, size, shape, boundary, internal echo, surrounding echo, rear echo, axillary lymph node, and the relation with the surrounding tissues. The lesion resistance index (RI was measured. Results: CDFI results showed that 3 were CF, 35 were PR, 20 were SD, and 2 were PD, with a diagnostic sensitivity of 80.6% and coincidence rate of 68.3%. After NCT, the length, width, thickness, area, and volume of the lesions were significantly reduced when compared with before NCT. The comparison of the evaluation of the boundary resolution and echo of the lesions by CDFI before and after NCT was statistically significant. The pathological results showed that 31 were effective, and 29 were invalid, among which RI in the effective group was significantly reduced when compared with before NCT, while RI in the invalid group was not significantly different from that before NCT. Conclusions: The efficacy evaluation of NCT by CDFI is highly consistent with the pathology. CDFI in evaluating the size, boundary, echo, and blood flow indicators of the lesions is of great scientificity and clinical application value.

  12. Turbo machine tip clearance and vibration measurements using a fibre optic laser Doppler position sensor

    Science.gov (United States)

    Pfister, T.; Büttner, L.; Czarske, J.; Krain, H.; Schodl, R.

    2006-07-01

    This paper presents a novel fibre optic laser Doppler position sensor for single blade tip clearance and vibration measurements at turbo machines, which offers high temporal resolution and high position resolution simultaneously. The sensor principle is based on the generation of a measurement volume consisting of two superposed fan-like interference fringe systems with contrary fringe spacing gradients using wavelength division multiplexing. A flexible and robust measurement system with an all-passive fibre coupled measurement head has been realized employing diffractive and refractive optics. Measurements of tip clearance and rotor vibrations at a transonic centrifugal compressor performed during operation at up to 50 000 rpm (833 Hz) corresponding to 21.7 kHz blade frequency and 586 m s-1 blade tip velocity are presented. The results are in excellent agreement with those of capacitive probes. The mean uncertainty of the position measurement was around 20 µm and, thus, considerably better than for conventional tip clearance probes. Consequently, this sensor is capable of fulfilling the requirements for future active clearance control systems and has great potential for in situ and online tip clearance and vibration measurements at metallic and non-metallic turbine blades with high precision.

  13. Evaluation the index of ophthalmic arteries in diabetic patients with retinopathy compared to diabetic patients without retinopathy using color Doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Mohammad Ghasem Hanafi

    2016-12-01

    Full Text Available Diabetic retinopathy is the most common eye complication in diabetic patients that early detection of this complication is essential. The aim of this study was to evaluate ophthalmic artery index in diabetic retinopathy by Doppler ultrasound. . In this cross-sectional study, 64 patients were studied in 4 groups (healthy, diabetic without retinopathy, background retinopathy and proliferative retinopathy. Resistance index (RI and Pulsatile Index (PI were assessed by color Doppler ultrasound. The obtained data were analyzed by ANOVA and chi-square test and ROC curve. RI in diabetic patients with proliferative retinopathy has the highest mean (0.83 and the lowest mean was observed in healthy subjects (0.54 (P <0.001 as well as in PI, the highest rate was in diabetic patients with proliferative retinopathy (1.41 and the lowest was in healthy subjects (0.92 (P <0.001. The results of our study showed that the sensitivity, specificity, positive and negative predictive values and overall accuracy of RI and PI in diabetic patients with proliferative retinopathy in the best cut-off points (0.645 and 1.0175 respectively were 100%.Ophthalmic artery index RI and PI was significantly increased in patients with diabetic retinopathy and the sensitivity and specificity for detection retinopathy was 100%. Color Doppler ultrasound method is more efficient for screening diabetic patients with retinopathy.

  14. MEMS-based handheld fourier domain Doppler optical coherence tomography for intraoperative microvascular anastomosis imaging.

    Directory of Open Access Journals (Sweden)

    Yong Huang

    Full Text Available To demonstrate the feasibility of a miniature handheld optical coherence tomography (OCT imager for real time intraoperative vascular patency evaluation in the setting of super-microsurgical vessel anastomosis.A novel handheld imager Fourier domain Doppler optical coherence tomography based on a 1.3-µm central wavelength swept source for extravascular imaging was developed. The imager was minimized through the adoption of a 2.4-mm diameter microelectromechanical systems (MEMS scanning mirror, additionally a 12.7-mm diameter lens system was designed and combined with the MEMS mirror to achieve a small form factor that optimize functionality as a handheld extravascular OCT imager. To evaluate in-vivo applicability, super-microsurgical vessel anastomosis was performed in a mouse femoral vessel cut and repair model employing conventional interrupted suture technique as well as a novel non-suture cuff technique. Vascular anastomosis patency after clinically successful repair was evaluated using the novel handheld OCT imager.With an adjustable lateral image field of view up to 1.5 mm by 1.5 mm, high-resolution simultaneous structural and flow imaging of the blood vessels were successfully acquired for BALB/C mouse after orthotopic hind limb transplantation using a non-suture cuff technique and BALB/C mouse after femoral artery anastomosis using a suture technique. We experimentally quantify the axial and lateral resolution of the OCT to be 12.6 µm in air and 17.5 µm respectively. The OCT has a sensitivity of 84 dB and sensitivity roll-off of 5.7 dB/mm over an imaging range of 5 mm. Imaging with a frame rate of 36 Hz for an image size of 1000(lateral×512(axial pixels using a 50,000 A-lines per second swept source was achieved. Quantitative vessel lumen patency, lumen narrowing and thrombosis analysis were performed based on acquired structure and Doppler images.A miniature handheld OCT imager that can be used for intraoperative evaluation of

  15. Demonstration of blood flow by color doppler in the femoral artery distal to arterial cannula during peripheral venoarterial-extracorporeal membrane oxygenation

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    K G Suresh Rao

    2017-01-01

    Full Text Available In spite of distal perfusion of the limb using a cannula, the limb can have ischemic events if there is an undetected kink or clot anywhere in the line or thrombus in the artery. There are several ways to monitor and assess the limb ischemia. Monitoring for clinical signs of limb ischemia like temperature change and pallor is reliable and mandatory. We report a method where we used color Doppler to document the blood flow. Curvilinear vascular probe of an echo machine is used to identify the flow in the distal femoral artery of the lower limb. . As we have demonstrated in the video attached, once flow to the distal limb perfusion system is shut off by closing the three way stop cock, we can appreciate the immediate cessation of flow in the artery by Doppler.

  16. Quantitative comparison of disc rim color in optic nerve atrophy of compressive optic neuropathy and glaucomatous optic neuropathy.

    Science.gov (United States)

    Nakano, Eri; Hata, Masayuki; Oishi, Akio; Miyamoto, Kazuaki; Uji, Akihito; Fujimoto, Masahiro; Miyata, Manabu; Yoshimura, Nagahisa

    2016-08-01

    The purpose was to investigate an objective and quantitative method to estimate the redness of the optic disc neuroretinal rim, and to determine the usefulness of this method to differentiate compressive optic neuropathy (CON) from glaucomatous optic neuropathy (GON). In our study there were 126 eyes: 40 with CON, 40 with normal tension glaucoma (NTG), and 46 normal eyes (NOR). Digital color fundus photographs were assessed for the redness of disc rim color using ImageJ software. We separately measured the intensity of red, green, and blue pixels from RGB images. Three disc color indices (DCIs), which indicate the redness intensity, were calculated through existing formulas. All three DCIs of CON were significantly smaller than those of NOR (P  -6 dB), in which the extent of retinal nerve fiber layer thinning is comparable, the DCIs of mild CON were significantly smaller than those of mild NTG (P optic disc color was useful in differentiating early-stage CON from GON and NOR.

  17. Doppler optical coherence tomography imaging of local fluid flow and shear stress within microporous scaffolds

    Science.gov (United States)

    Jia, Yali; Bagnaninchi, Pierre O.; Yang, Ying; Haj, Alicia El; Hinds, Monica T.; Kirkpatrick, Sean J.; Wang, Ruikang K.

    2009-05-01

    Establishing a relationship between perfusion rate and fluid shear stress in a 3D cell culture environment is an ongoing and challenging task faced by tissue engineers. We explore Doppler optical coherence tomography (DOCT) as a potential imaging tool for in situ monitoring of local fluid flow profiles inside porous chitosan scaffolds. From the measured fluid flow profiles, the fluid shear stresses are evaluated. We examine the localized fluid flow and shear stress within low- and high-porosity chitosan scaffolds, which are subjected to a constant input flow rate of 0.5 ml.min-1. The DOCT results show that the behavior of the fluid flow and shear stress in micropores is strongly dependent on the micropore interconnectivity, porosity, and size of pores within the scaffold. For low-porosity and high-porosity chitosan scaffolds examined, the measured local fluid flow and shear stress varied from micropore to micropore, with a mean shear stress of 0.49+/-0.3 dyn.cm-2 and 0.38+/-0.2 dyn.cm-2, respectively. In addition, we show that the scaffold's porosity and interconnectivity can be quantified by combining analyses of the 3D structural and flow images obtained from DOCT.

  18. Functional evaluation of the urinary tract by color-Doppler ultrasonography (CDU) in 100 patients with renal colic

    Energy Technology Data Exchange (ETDEWEB)

    Pepe, Pietro E-mail: piepepe@hotmail.com; Motta, Luigi; Pennisi, Michele; Aragona, Francesco

    2005-01-01

    Introduction and objective: To evaluate if the addition of a renal color-Doppler ultrasonography (CDU) in the setting of acute renal colic improves the sensitivity of conventional sonography. Materials and methods: Between July 2002 and June 2003, 100 patients (median 49 years) with renal colic have been evaluated. Within 24 h of the admission, a CDU study of the urinary tract was performed using a sonograph GE Logiq 500 PRO with a multifrequency (3-5 MHz) convex probe. The following parameters were evaluated: ultrasonography (US) of both kidneys, ureters and bladder; resistive index (RI) of the arciform arteries of both kidneys in three different parenchymal areas; ureteric jets in response to hydration. A renal RI >0.70 and/or a 10% difference between the kidneys were considered as diagnostic of obstructive uropathy; an asymmetric and/or reduced ureteric jet from the ureteric orifices was an additional indicator of obstruction. All patients underwent a CT scan both with and without the administration of contrast medium. Results: Enhanced helical CT demonstrated an urinary stone in 90 out of the 100 patients (90%): 29 pyelic, 28 at the pyelo-ureteral junction, 23 lumbo-iliac and 10 juxtavesical stones. Among 90 patients with urolithiasis, the stone was undetectable with US in 11 cases (12.2%); in 8 cases (8.9%) pyelocalicectasis was absent, and in 6 patients (6.6%) a non-obstructive hydronephrosis was present. Median RI in obstructed and non-obstructed kidney was 0.73 (range 0.71-0.87) versus 0.62 (0.50-0.68), respectively; in two, obstructed kidneys RI was <0.70 but greater than 10% compared with normal side. Sensitivity and specificity of US, CDU (RI + ureteric jet), unenhanced helical CT and CDU in association with unenhanced helical CT were 94.8 and 55.5, 98.9 and 90.9, 100 and 100%, respectively. Discussion and conclusions: CDU in patients with renal colic and/or pelvicalicectasis improves the diagnostic accuracy of US in distinguishing between obstructive

  19. Color Doppler imaging and measurements of intraovarian and intrauterine vascularization on basal ultrasound examination in spontaneous ovulatory and anovulatory cycles

    Directory of Open Access Journals (Sweden)

    Kutlešić Ranko

    2008-01-01

    Full Text Available Background/Aim. Any organs functioning directly depends on vascularization. It applies also to the uterus and ovary which go through changes of vascularization during a menstruation cycle. The aim of this investigation was to determine differences in intrauterine and ovarian stromal arterioral blood flow on basal ultrasound examination (day 2-4 between spontaneous ovulatory and anovulatory cycles. Methods. This prospective clinical investigation included 205 patients divided into two groups: with ovulatory and with anovulatory cycles. Results. Resistance to ovarian arterioral stromal blood flow was significantly lower in the patients with ovulatory cycles (pulsatile index - PI 0.97 ± 0.4 vs 1.93 ± 1.37; p = 0.001737; and (resistance index - RI 0.55 ± 0.12 vs 0.68 ± 0.14; p = 0.040033. There were no statistically significant differences in arcuate arterioral blood flow in the pateints with ovulatory and anovulatory cycles (PI 1.21 ± 0.34 vs 61 ± 0,61 p = 0.136161 and RI 0.64 ± 0.11 vs 0.74 ± 0.07; p = 0.136649. The patients with ovulatory cycles had lower uterine radial arterioral blood flow than the patients with anovulatory cycles (PI 1.001 ± 0.22 vs 1.61 ± 0.23 p = 0.007501 and RI 0.55 ± 0.08 vs 0.71 ± 0.12; p = 0,0460113. The patients with ovulatory cycles had lower subendometrial arterioral blood flow resistance (PI 0.69 ± 0.19 vs 1.385±0.09; p = 0.00622 and RI 0.44 ± 0.09 vs 0.65 ± 0.02; p = 0.027458. Conclusion. Color Doppler ultrasuond imaging and measurements of intrauterine and ovarian stromal arterioral blood flow on basal ultrasound examination (day 2-4, showed lower resistance to blood flow in ovulatory than in anovulatory cycles.

  20. Transient basilar artery occlusion monitored by transcranial color Doppler presenting with a spectacular shrinking deficit: a case report

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    Del Sette Massimo

    2010-01-01

    Full Text Available Abstract Introduction We describe the case of a 79-year-old Caucasian Italian woman with a transient basilar occlusion monitored by transcranial Doppler, with subsequent recanalization and clinical shrinking deficit. This is the first case of transient basilar occlusive disease diagnosed and monitored by transcranial Doppler. This case is important and needs to be reported because transient basilar occlusion may be easily diagnosed if transcranial Doppler is performed. Case presentation A 79-year-old woman affected by chronic atrial fibrillation and not treated with oral anticoagulants, cardioverted to sinus rhythm during a gastric endoscopy. She then showed a sudden-onset loss of consciousness, horizontal and vertical gaze palsy, tetraparesis and bilateral miosis and coma. Two hours later, the symptoms resolved quickly, leaving no residual neurologic deficits. Transcranial Doppler examination showed a dampened flow in the basilar artery in the emergency examination and a restored flow when the symptoms resolved. Conclusion This is the first case of transient basilar occlusive disease diagnosed and monitored by transcranial Doppler. We believe that transcranial Doppler should be performed in all cases of unexplained acute loss of consciousness, in particular, if associated with signs of brainstem dysfunctions.

  1. Relationship between hemodynamic changes of portal vein and hepatic artery measured by color Doppler ultrasound and FibroScan value in patients with liver cirrhosis

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    CHENG Xiaofei

    2014-11-01

    Full Text Available ObjectiveTo explore the relationship between hemodynamic changes of the portal vein and hepatic artery measured by color Doppler ultrasound and FibroScan value in patients with liver cirrhosis. MethodsA total of 192 patients with hepatitis B cirrhosis who were admitted to our hospital from March 2010 to December 2013, as well as 100 healthy persons, were recruited. The mean portal vein blood flow velocity (PVVmean, hepatic artery pulsatility index (HAPI, and hepatic artery resistance index (HARI were measured by color Doppler ultrasound. FibroScan was also carried out. All data were statistically analyzed using SPSS 13.0. Continuous data were expressed as mean±SD and compared between groups by t-test. ResultsThe HAPI, HARI, and FibroScan value of the patient group were 1.56±024, 0.73±0.05, and 25.38±7.73, respectively, significantly higher than those of the control group (1.36±0.14, 0.65±0.07, and 7.8±3.6 (P<0.05; the PVVmean of the patient group was 14.43±1.86, significantly lower than that of the control group (17.35±0.56 (P<0.05. FibroScan value was positively correlated with HAPI and HARI (r1=0.59, r2=0.66, P<0.001, but negatively correlated with PVVmean (r=-0.64, P<0.001. ConclusionThe liver stiffness assessed by FibroScan and the hemodynamic changes of the portal vein and hepatic artery measured by color Doppler ultrasound are vitally important for evaluating the severity of liver cirrhosis.

  2. Mitral valve coaptation and its relationship to late diastolic flow: A color Doppler and vector flow map echocardiographic study in normal subjects.

    Science.gov (United States)

    Sherrid, Mark V; Kushner, Josef; Yang, Georgiana; Ro, Richard

    2017-04-01

    Three competing theories about the mechanism of mitral coaptation in normal subjects were evaluated by color Doppler and vector flow mapping (VFM): (1) beginning of ventricular (LV) ejection, (2) "breaking of the jet" of diastolic LV inflow, and (3) returning diastolic vortices impacting the leaflets on their LV surfaces. We analyzed 80 color Doppler frames and 320 VFM measurements. In all 20 normal subjects, coaptation occurred before LV ejection, 78±16 ms before onset. On color Doppler frames the larger anterior, and smaller posterior vortices circle back and, in all cases, strike the ventricular surfaces of the leaflets. On the first closing-begins frame, for the first time, vortex velocity normal to the ventricular surface of the anterior leaflet (AML) is greater than that in the mitral orifice, and the angle of attack of LV vortical flow onto the AML is twice as high as the angle of flow onto the valve in orifice. Thus, at the moment coaptation begins, vortical flow strikes the mitral leaflet with higher velocity, and higher angle of attack than orifice flow, and thus with greater force. According to the "breaking of the jet" theory, one would expect to see de novo LV flow perpendicular to the leaflets beginning after transmitral flow terminates. Instead, the returning continuous LV vortical flow that impacts the valve builds continuously after the P-wave. Late diastolic vortices strike the ventricular surfaces of the mitral leaflets and contribute to valve coaptation, permitted by concomitant decline in transmitral flow. © 2017, Wiley Periodicals, Inc.

  3. The use of the color Doppler ultrasonography in the diagnosis and monitoring of an atypical case of giant-cell arteritis

    Directory of Open Access Journals (Sweden)

    Nádia Martins

    2016-04-01

    Full Text Available Giant Cell Arteritis (GCA is a large vessels vasculitis that is typically characterised by headache, scalp tenderness, jaw claudication and visual disturbances. Temporal arteries color Doppler ultrasonography (CDUS is a sensitive and non-invasive image technique used in the diagnosis of this disease. This work highlights the importance of CDUS in the diagnostic workup of GCA and also demonstrates it´s usefullness in the evaluation and documentation of the response to corticosteroids therapy in an atypical case of ACG.

  4. Associations between abnormal ultrasound color Doppler measures and tendon pain symptoms in badminton players during a season: a prospective cohort study.

    Science.gov (United States)

    Boesen, Anders Ploug; Boesen, Morten Ilum; Torp-Pedersen, Soren; Christensen, Robin; Boesen, Lars; Hölmich, Per; Nielsen, Michael Bachmann; Koenig, Merete Juhl; Hartkopp, Andreas; Ellegaard, Karen; Bliddal, Henning; Langberg, Henning

    2012-03-01

    Color Doppler ultrasound is widely used to examine intratendinous flow in individuals with overuse tendon problems, but the association between color Doppler and pain is still unclear. Intratendinous flow is present and associated with pain in badminton players, and intratendinous flow and pain increase during a badminton season. Cohort study (prognosis); Level of evidence, 2. Ninety-five semiprofessional badminton players were included in the study at a tournament at the start of the badminton season. All players were interviewed regarding pain. The anterior knee tendons and Achilles tendons were studied. Each tendon was scored using a quantitative grading system (grades 0-5) and a qualitative scoring system (color fraction) using color Doppler ultrasound. Eight months later, 86 of the players (91%) were retested by the same investigators during an equivalent badminton tournament (including 1032 tendon regions; 86 players with 4 tendons each with 3 regions), thus forming the study group. At the start of the season, 24 players (28%) experienced pain in 37 tendons (11%), and at the end of the season, 31 players (36%) experienced pain in 51 tendons (15%), which was a statistically significant increase (P = .0002). Abnormal flow was found in 230 tendon regions in 71 players (83%) at the start of the season compared with 78 tendon regions in 41 players (48%) at the follow-up. The decrease in abnormal flow was statistically significant (P < .0001). Of the 37 painful tendons at the start of the season, 25 had abnormal flow (68%). In contrast, 131 tendons (85%) with abnormal flow at the start of the season were pain free. At the end of the season, 18 of the 51 painful tendons (35%) had abnormal flow. Ninety-six of the 131 pain-free tendons (73%) with abnormal flow at the start of the season were normalized (no pain and normal flow) at the end of the season. It was not possible to verify any association between intratendinous flow and pain at the start of the season or at

  5. Note: Pulsed single longitudinal mode optical parametric oscillator for sub-Doppler spectroscopy of jet cooled transient species

    Science.gov (United States)

    Zhang, Qiang; Zhu, Boxing; Zhang, Deping; Gu, Jingwang; Zhao, Dongfeng; Chen, Yang

    2017-12-01

    We present a pulsed single longitudinal mode optical parametric oscillator that was recently constructed for sub-Doppler spectroscopic studies of transient species in a supersonic slit jet expansion environment. The system consists of a Littman-type grazing-incidence-grating resonator and a KTP crystal and is pumped at 532 nm. By spatially filtering the pump laser beam and employing an active cavity-length-stabilization scheme, a frequency down-conversion efficiency up to 18% and generation of Fourier-transform limited pulses with a typical pulse duration of ˜5.5 ns and a bandwidth less than 120 MHz have been achieved. In combination with a slit jet expansion, a sub-Doppler spectrum of SiC2 has been recorded at ˜498 nm, showing a spectral resolution of Δν/ν ≈ 6.2 × 10-7.

  6. Apparent diffusion coefficient of renal parenchyma and color Doppler ultrasound of intrarenal arteries in patients with cirrhosis related renal dysfunction

    Directory of Open Access Journals (Sweden)

    Mohamed M Hefeda

    2014-12-01

    Conclusion: Liver cirrhosis, even in the presence of refractory ascites, did not affect the ADC value of renal parenchyma, however ADC value is affected in renal parenchyma of patients with hepato-renal syndrome. Duplex-Doppler ultrasound of intrarenal arteries enables the early detection of renal hemodynamic disturbances in patients with liver cirrhosis.

  7. SWIM: A Semi-Analytical Ocean Color Inversion Algorithm for Optically Shallow Waters

    Science.gov (United States)

    McKinna, Lachlan I. W.; Werdell, P. Jeremy; Fearns, Peter R. C. S.; Weeks, Scarla J.; Reichstetter, Martina; Franz, Bryan A.; Shea, Donald M.; Feldman, Gene C.

    2014-01-01

    Ocean color remote sensing provides synoptic-scale, near-daily observations of marine inherent optical properties (IOPs). Whilst contemporary ocean color algorithms are known to perform well in deep oceanic waters, they have difficulty operating in optically clear, shallow marine environments where light reflected from the seafloor contributes to the water-leaving radiance. The effect of benthic reflectance in optically shallow waters is known to adversely affect algorithms developed for optically deep waters [1, 2]. Whilst adapted versions of optically deep ocean color algorithms have been applied to optically shallow regions with reasonable success [3], there is presently no approach that directly corrects for bottom reflectance using existing knowledge of bathymetry and benthic albedo.To address the issue of optically shallow waters, we have developed a semi-analytical ocean color inversion algorithm: the Shallow Water Inversion Model (SWIM). SWIM uses existing bathymetry and a derived benthic albedo map to correct for bottom reflectance using the semi-analytical model of Lee et al [4]. The algorithm was incorporated into the NASA Ocean Biology Processing Groups L2GEN program and tested in optically shallow waters of the Great Barrier Reef, Australia. In-lieu of readily available in situ matchup data, we present a comparison between SWIM and two contemporary ocean color algorithms, the Generalized Inherent Optical Property Algorithm (GIOP) and the Quasi-Analytical Algorithm (QAA).

  8. Optical microscope using an interferometric source of two-color, two-beam entangled photons

    Science.gov (United States)

    Dress, William B.; Kisner, Roger A.; Richards, Roger K.

    2004-07-13

    Systems and methods are described for an optical microscope using an interferometric source of multi-color, multi-beam entangled photons. A method includes: downconverting a beam of coherent energy to provide a beam of multi-color entangled photons; converging two spatially resolved portions of the beam of multi-color entangled photons into a converged multi-color entangled photon beam; transforming at least a portion of the converged multi-color entangled photon beam by interaction with a sample to generate an entangled photon specimen beam; and combining the entangled photon specimen beam with an entangled photon reference beam within a single beamsplitter. An apparatus includes: a multi-refringent device providing a beam of multi-color entangled photons; a condenser device optically coupled to the multi-refringent device, the condenser device converging two spatially resolved portions of the beam of multi-color entangled photons into a converged multi-color entangled photon beam; a beam probe director and specimen assembly optically coupled to the condenser device; and a beam splitter optically coupled to the beam probe director and specimen assembly, the beam splitter combining an entangled photon specimen beam from the beam probe director and specimen assembly with an entangled photon reference beam.

  9. Ages of galaxy bulges and disks from optical and near-infrared colors

    NARCIS (Netherlands)

    Peletier, RF; Balcells, M

    We compare optical and near-infrared colors of disks and bulges in a diameter-limited sample of inclined, bright, nearby, early-type spirals. Color profiles along wedge apertures at 15 degrees from the major axis and on the minor axis on the side of the galaxy opposite to the dust lane are used to

  10. Functional photoreceptor loss revealed with adaptive optics: an alternate cause of color blindness.

    Science.gov (United States)

    Carroll, Joseph; Neitz, Maureen; Hofer, Heidi; Neitz, Jay; Williams, David R

    2004-06-01

    There is enormous variation in the X-linked L/M (long/middle wavelength sensitive) gene array underlying "normal" color vision in humans. This variability has been shown to underlie individual variation in color matching behavior. Recently, red-green color blindness has also been shown to be associated with distinctly different genotypes. This has opened the possibility that there may be important phenotypic differences within classically defined groups of color blind individuals. Here, adaptive optics retinal imaging has revealed a mechanism for producing dichromatic color vision in which the expression of a mutant cone photopigment gene leads to the loss of the entire corresponding class of cone photoreceptor cells. Previously, the theory that common forms of inherited color blindness could be caused by the loss of photoreceptor cells had been discounted. We confirm that remarkably, this loss of one-third of the cones does not impair any aspect of vision other than color.

  11. Nonlinear narrow Doppler-free resonances for optical transitions and annihilation radiation of a positronium atom

    International Nuclear Information System (INIS)

    Letokhov, V.S.; Minogin, V.G.

    1976-01-01

    The possibilities of obtaining narrow resonances without the Doppler broadening for transition between the fine structure levels of the ground and first excited states of a positronium atom are considered. An analysis is carried out of the conditions required for observation of the narrow resonances of saturation of single quantum absorption in the 1S-2P transitions and observation of narrow two-photon absorption resonances in the 1S-2S transitions. It is shown that narrow 2γ annihilation radiation lines of a positronium atom may be obtained with a width much smaller than the Doppler one

  12. Flagging optically shallow pixels for improved analysis of ocean color data

    Science.gov (United States)

    McKinna, L. I. W.; Werdell, J.; Knowles, D., Jr.

    2016-02-01

    Ocean color remote-sensing is routinely used to derive marine geophysical parameters from sensor-observed water-leaving radiances. However, in clear geometrically shallow regions, traditional ocean color algorithms can be confounded by light reflected from the seafloor. Such regions are typically referred to as "optically shallow". When performing spatiotemporal analyses of ocean color datasets, optically shallow features such as coral reefs can lead to unexpected regional biases. Benthic contamination of the water-leaving radiance is dependent on bathymetry, water clarity and seafloor albedo. Thus, a prototype ocean color processing flag called OPTSHAL has been developed that takes all three variables into account. In the method described here, the optical depth of the water column at 547 nm, ζ(547), is predicted from known bathymetry and estimated inherent optical properties. If ζ(547) is less then the pre-defined threshold, a pixel is flagged as optically shallow. Radiative transfer modeling was used to identify the appropriate threshold value of ζ(547) for a generic benthic sand albedo. OPTSHAL has been evaluated within the NASA Ocean Biology Processing Group's L2GEN code. Using MODIS Aqua imagery, OPTSHAL was tested in two regions: (i) the Pedro Bank south-west of Jamaica, and (ii) the Great Barrier Reef, Australia. It is anticipated that OPTSHAL will benefit end-users when quality controlling derived ocean color products. Further, OPTSHAL may prove useful as a mechanism for switching between optically deep and shallow algorithms during ocean color processing.

  13. Decision making in the treatment of peripheral arterial disease - A single-institution comparative study using information from color doppler and digital subtraction angiogram studies

    International Nuclear Information System (INIS)

    Koshy, Chiramel G; Chacko, Binita R; Keshava, Shyamkumar N; Stephen, Edwin; Agarwal, Sunil

    2011-01-01

    Numerous studies have compared the accuracy of color Doppler (CD) with that of digital subtraction angiography (DSA) in the diagnosis of peripheral arterial disease (PAD). However, only a few have looked at the influence of these diagnostic tests on the treatment decision in PAD. This study evaluated the differences in treatment decisions that were based on CD and with those based on DSA findings. Findings from CD and DSA studies obtained in 40 patients were entered on line diagrams by two radiologists working separately. These were randomized and sent to three experienced clinicians – two vascular surgeons and one interventional radiologist. The treatment decisions of the clinicians based on each proforma were collected and analyzed to look for the degree of agreement between Doppler-based and DSA-based decisions. There was fair to moderate agreement between CD-based and DSA-based decisions for all three clinicians, with some improvement in agreement with the addition of clinical data. The vascular surgeons showed better agreement with each other on treatment decisions compared to the interventional radiologist who showed a fair-to-moderate level of agreement with the vascular surgeons, which did not significantly change with the addition of clinical data. There is a fair to moderate agreement between treatment decisions based on CD findings and those based on DSA findings. We conclude that CD along with clinical data is sufficient to make decisions in the treatment of PAD

  14. Spontaneous development of bilateral subdural hematomas in an infant with benign infantile hydrocephalus: color Doppler assessment of vessels traversing extra-axial spaces

    Energy Technology Data Exchange (ETDEWEB)

    Amodio, John; Spektor, Vadim; Pramanik, Bidyut; Rivera, Rafael; Pinkney, Lynne; Fefferman, Nancy [New York University Medical Center, Department of Radiology, New York, NY (United States)

    2005-11-01

    We present an infant with macrocrania, who initially demonstrated prominent extra-axial fluid collections on sonography of the brain, compatible with benign infantile hydrocephalus (BIH). Because of increasing macrocrania, a follow-up sonogram of the brain was performed; it revealed progressive enlargement of the extra-axial spaces, which now had echogenic debris. Color Doppler US showed bridging veins traversing these extra-axial spaces, so it was initially thought that these spaces were subarachnoid in nature (positive cortical vein sign). However, an arachnoid membrane was identified superior to the cortex, and there was compression of true cortical vessels beneath this dural membrane. An MRI of the brain showed the extra-axial spaces to represent bilateral subdural hematomas. The pathogenesis of spontaneous development of the subdural hematomas, in the setting of BIH, is discussed. We also emphasize that visualizing traversing bridging veins through extra-axial spaces does not necessarily imply that these spaces are subarachnoid in origin. (orig.)

  15. Avaliação do bem-estar fetal pela dopplervelocimetria com mapeamento em cores Evaluation of fetal well-being through color doppler velocimetry

    Directory of Open Access Journals (Sweden)

    Cleide Mara Mazzotti de Oliveira Franzin

    1999-01-01

    aorta, and the adverse perinatal results was established. The pregnant women selected for this study were submitted electively to cesarean sections, at the utmost four hours after the color Doppler examination. We considered as adverse perinatal results: Apgar score lower than seven at the 5th minute, neonatal intensive care unit hospitalization, intrauterine growth retardation, acute fetal distress, perinatal mortality, hypoglycemia, polycythemia, necrotizing enterocolitis, and cerebral hemorrhage. The indexes for the umbilical and middle cerebral arteries and the abdominal aorta were related, in each case, to the adverse perinatal results. Results: the systole/diastole umbilical artery ratio presented a higher sensitivity than the pulsatile and tolerance indexes. The Doppler study of the umbilical artery presented greater sensitivity than the middle cerebral artery and the abdominal aorta in detecting adverse perinatal results. Conclusion: the Doppler velocimetry of the umbilical and middle cerebral arteries presented good diagnostic capacity in evaluating fetal well-being, and a significant association with the adverse perinatal results.

  16. Fiber optics reflectance spectroscopy (45°x: 45°) for color analysis of dental composite.

    Science.gov (United States)

    Gargano, Marco; Ludwig, Nicola; Federighi, Veronica; Sykes, Ros; Lodi, Giovanni; Sardella, Andrea; Carrassi, Antonio; Varoni, Elena M

    2016-08-01

    To evaluate the application of a fiber optic reflectance spectroscopy (FORS) prototype probe for 45°x: 45° FORS for determining color of dental materials. A portable spectrophotometer with a highly manageable fiber optics co-axial probe was used to apply 45°x: 45° FORS for color matching in restorative dentistry. The color coordinates in CIELAB space of two dental shade guides and of the corresponding photopolymerized composites were collected and compared. The 45°x: 45° FORS with the co-axial probe (test system), the integrating sphere spectroscopy (reference system) and a commercial dental colorimeter (comparator system) were used to collect data and calculate color differences (ΔE and ΔE00). FORS system displayed high repeatability, reproducibility and accuracy. ΔE and ΔE00 values between the shade-guide, each other, and the corresponding composites resulted above the clinically acceptable limit. The 45°x: 45° FORS test system demonstrated suitable in vitro performance for dental composite color evaluation. 45°x: 45° fiber optic reflectance spectroscopy allows reliable color analysis of small surfaces of dental composites, favoring the color matching of material with the closely surrounding dental tissue, and confirming significant color differences between shade guide tabs and photo-polymerized composites.

  17. Optical determination and magnetic manipulation of a single nitrogen-vacancy color center in diamond nanocrystal

    International Nuclear Information System (INIS)

    Diep Lai, Ngoc; Zheng, Dingwei; Treussart, François; Roch, Jean-François

    2010-01-01

    The controlled and coherent manipulation of individual quantum systems is fundamental for the development of quantum information processing. The nitrogen-vacancy (NV) color center in diamond is a promising system since its photoluminescence is perfectly stable at room temperature and its electron spin can be optically read out at the individual level. We review here the experiments currently realized in our laboratory concerning the use of a single NV color center as the single photon source and the coherent magnetic manipulation of the electron spin associated with a single NV color center. Furthermore, we demonstrate a nanoscopy experiment based on the saturation absorption effect, which allows to optically pin-point a single NV color center at sub-λ resolution. This offers the possibility to independently address two or multiple magnetically coupled single NV color centers, which is a necessary step towards the realization of a diamond-based quantum computer

  18. Probability of malignancy in non-palpable thyroid nodules. Predictive value of color Doppler ultrasound and cytological correlation

    International Nuclear Information System (INIS)

    Perez Espinosa Sebastian; Pineda Ordonez, Diego; Garcia, Sandra; Costilla, Mariela

    2011-01-01

    Objective: To evaluate the diagnostic accuracy of ultrasound and Doppler criteria in the differentiation of malignant nodules, using cytological diagnosis as standard reference. Material and Method: Prospective observational study in 200 patients, between March-September 2008, assessed for known thyroid nodular disease using FNA. The probability of malignancy was categorized as low (0-3), intermediate (4-7) or high (greater than 7). The procedures were performed using Medison Sonoline ultrasound equipment, with a linear transducer (7.5 MHz), and the aspiration was performed with a 25 G needle and sent to cytology immediately. A single sample was needed in 88% of cases. Results: Approximately 96% of the nodules that went to cytology were categorized as low-grade, 3% as intermediate and 1% as high, without significant differences (p>0.5) when compared with the ultrasound score. Sonographic features indicating a high probability of malignancy were found in 2% (n=5) of cases, and the diagnosis was confirmed by cytology in 2 cases. Malignancy criteria such as size (>1 cm), irregular contours, solid echo structure, calcifications, and intranodal Doppler showed variable sensitivity and specificity (S: 32-44% and E: 28-55%) with overlapping confidence intervals within lesions of intermediate and low probability. Low probability lesions showed isoechogenicity, regular contours, lack of calcifications and intralesional Doppler, for a negative predictive value of 62-77%. Conclusion: Our results suggest that overlapping sonographic features between benign and malignant nodules requires final cytological diagnosis in most cases, given the safety of the cytological technique and the short waiting time.

  19. Doppler color flow analysis of the uterine arteries before and after intrauterine device insertion: a prospective study.

    Science.gov (United States)

    de Souza, Marco Aurélio Martins; Geber, Selmo

    2006-02-01

    An intrauterine device (IUD) is one of the most frequently used methods of birth control around the world. Although a relationship between its use and menstrual disorders has been well documented, only a few studies have tried to show whether there are any vascular modifications. The aim of our study was to evaluate the influence of an IUD on uterine artery blood flow using Doppler assessment. A total of 100 patients selected for IUD use were prospectively evaluated with Doppler analysis before and 30 days after insertion. The resistive index (RI) and pulsatility index (PI) were used to evaluate uterine artery vascular resistance. Patients were allocated in 2 groups according to whether they were (group 2) or were not (group 1) lactating. The PI and RI of the patients in groups 1 and 2 before and after IUD insertion were not statistically significantly different (P = .298 and .23). When we compared uterine artery blood flow indices before and after IUD insertion for groups 1 and 2 separately, we observed in group 1 that the mean +/- SD PI values were 2.45 +/- 0.62 and 2.55 +/- 0.55 (P = .38) and the RI values were 0.87 +/- 0.08 and 0.87 +/- 0.06 (P = .88) before and after IUD insertion, respectively. In group 2, the PI values were 2.31 +/- 0.55 and 2.37 +/- 0.69 (P = .68) and the RI values were 0.85 +/- 0.07 and 0.86 +/- 0.07 (P = .44) before and after IUD insertion. Finally, we used the mean blood flow indices of the uterine arteries of all patients to compare the effect of IUD insertion. Results were also not statistically significant when we compared PI and RI before and after IUD insertion. The presence of an IUD does not interfere with the vascular resistance of the uterine arteries that can be shown by Doppler flow assessments 1 month after insertion.

  20. Synchronized epiaortic two-dimensional and color Doppler echocardiographic guidance enables routine ascending aortic cannulation in type A acute aortic dissection.

    Science.gov (United States)

    Inoue, Yoshito; Takahashi, Ryuichi; Ueda, Toshihiko; Yozu, Ryohei

    2011-02-01

    Preference for arterial inflow during surgery for type A acute aortic dissection remains controversial. Antegrade central perfusion prevents malperfusion and retrograde embolism, and the ascending aorta provides arterial access for rapid establishment of systemic perfusion, especially if there is hemodynamic instability. It has not been used routinely, however, because of the disruption caused to the aorta. We evaluated the safety and efficacy of routine cannulation of the dissected aorta for the repair of type A dissection. Surgical results were analyzed for 83 consecutive patients with type A acute aortic dissection between 2002 and 2009. They were treated surgically by prosthetic graft replacement under hypothermic circulatory arrest. The ascending aorta was routinely cannulated using the Seldinger technique with epiaortic echocardiographic guidance; antegrade systemic perfusion was evaluated by color Doppler ultrasound. Systemic antegrade perfusion via the dissected ascending aorta was performed safely in all cases. There was no malperfusion or thromboembolism as a result of ascending aortic cannulation. Epiaortic 2-dimensional and color Doppler imaging provided real-time monitoring adequate for the placement and for proper systemic perfusion. There were 5 in-hospital deaths (5/83=6.0%) and 8 strokes (preoperative 6/83=7.2%, postoperative 2/83=2.4%). A total of 78 patients (78/83=94%) were discharged and have been followed up without major adverse cardiac events for a mean duration of 31.8 months. Ascending aortic cannulation is a simple and safe technique that provides a rapid and reliable route of antegrade central systemic perfusion in type A aortic dissection. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  1. A study of the distribution of color Doppler flows in the superficial digital flexor tendon of young Thoroughbreds during their training periods.

    Science.gov (United States)

    Hatazoe, Takashi; Endo, Yoshiro; Iwamoto, Yohei; Korosue, Kenji; Kuroda, Taisuke; Inoue, Saemi; Murata, Daiki; Hobo, Seiji; Misumi, Kazuhiro

    2015-01-01

    Aim of this study was to evaluate the relationships of exercise and tendon injury with Doppler flows appearing in the superficial digital flexor tendon (SDFT) of young Thoroughbreds during training periods. The forelimb SDFTs of 24 one- to two-year-old Thoroughbreds clinically free of any orthopaedic disorders were evaluated using grey-scale (GS) and color Doppler (CD) images during two training periods between December 2013 to April 2015. Twelve horses per year were examined in December, February, and April in training periods that began in September and ended in April. The SDFT was evaluated in 3 longitudinal images of equal lengths (labelled 1, 2, 3 in order from proximal to distal), and 6 transversal images separated by equal lengths (labelled 1A, 1B, 2A, 2B, 3A and 3B in order from proximal to distal) of the metacarpus using both GS and CD. The running (canter and gallop) distance for 1 month before the date of the ultrasonographic examinations was increased in December, February, and April in both of the two training periods. CD flows defined as rhythmically blinking or pulsatory colored signals were found in 56 of 864 (6.4%) transversal CD images, in 28, 12, 13, and 3 images of 1A, 1B, 2A and 2B, respectively, and in 7, 14, and 35 images captured in December, February, and April, respectively. There were no longitudinal or transversal GS images indicating injury in the SDFTs in either of the two training periods. The increase of CD flows in the proximal regions of the SDFT are possibly related to the increase of the running distance during the training periods of the one- to two-year-old Thoroughbreds. Because no injury was diagnosed in the SDFTs by GS images during the training periods, the increase of CD flows in the proximal parts of SDFT is not necessarily predictive of tendon injury in the near future during the training period of young Thoroughbreds.

  2. 'Focal thyroid inferno' on color Doppler ultrasonography: A specific feature of focal Hashimoto's thyroiditis

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Xianshui, E-mail: fuxs1968@163.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Guo, Limei, E-mail: guolimei@bjmu.edu.cn [Department of Pathology, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Zhang, Huabin, E-mail: huabinzhang@bjmu.edu.cn [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Ran, Weiqiang, E-mail: ranwq-sina@vip.sina.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Fu, Peng, E-mail: fupeng01@gmail.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Li, Zhiqiang, E-mail: lizhq126@126.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Chen, Wen, E-mail: wendy7989@sina.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Jiang, Ling, E-mail: papayaling@yahoo.com.cn [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Wang, Jinrui, E-mail: jinrui_wang@sina.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China); Jia, Jianwen, E-mail: drjia88@sohu.com [Department of Ultrasound, Peking University Third Hospital, 49 Huayuanbeilu Road, Beijing 100191 (China)

    2012-11-15

    Purpose: To evaluate color-Doppler features predictive of focal Hashimoto's thyroiditis. Materials and methods: A total of 521 patients with 561 thyroid nodules that underwent surgeries or gun biopsies were included in this study. These nodules were divided into three groups: focal Hashimoto's thyroiditis (104 nodules in 101 patients), benignity other than focal Hashimoto's thyroiditis (73 nodules in 70 patients), and malignancy (358 nodules in 350 patients). On color Doppler sonography, four vascularity types were determined as: hypovascularity, marked internal flow, marked peripheral flow and focal thyroid inferno. The {chi}{sup 2} test was performed to seek the potential vascularity type with the predictive ability of certain thyroid pathology. Furthermore, the gray-scale features of each nodule were also studied. Results: The vascularity type I (hypovascularity) was more often seen in focal Hashimoto's thyroiditis than other benignity and malignancy (46% vs. 20.5% and 19%). While the type II (marked internal flow) showed the opposite tendency (26.9% [focal Hashimoto's thyroiditis] vs. 45.2% [other benignity] and 52.8% [malignancy]). However, type III (marked peripheral flow) was unable to predict any thyroid pathology. Importantly, type IV (focal thyroid inferno) was exclusive to focal Hashimoto's thyroiditis. All 8 type IV nodules appeared to be solid, hypoechoic, and well-defined. Using 'focal thyroid inferno' as an indicator of FHT, the diagnostic sensitivity and specificity were 7.7% and 100% respectively. Conclusions: The vascularity type of 'focal thyroid inferno' is specific for focal Hashimoto thyroiditis. Recognition of this particular feature may avoid unnecessary interventional procedures for some solid hypoechoic thyroid nodules suspicious of malignancy.

  3. [Chromaticity and optical spectrum colorimetry of the tongue color in different syndromes of primary hepatic carcinoma].

    Science.gov (United States)

    Xu, Ying; Zeng, Chang-chun; Cai, Xiu-yu; Guo, Rong-ping; Nie, Guang; Jin, Ying

    2012-11-01

    In this study, the optical data of tongue color of different syndromes in primary hepatic carcinoma (PHC) were detected by optical spectrum colorimetry, and the chromaticity of tongue color was compared and analyzed. The tongue color characteristics of different syndromes in PHC and the relationship between different syndromes and tongue color were also investigated. Tongue color data from 133 eligible PHC patients were collected by optical spectrum colorimetry and the patients were divided into 4 syndrome groups according to their clinical features. The syndrome groups were liver depression and spleen deficiency (LDSD), accumulation of damp-heat (ADH), deficiency of liver and kidney yin (DLKY), and qi stagnation and blood stasis (QSBS). The variation characteristics of chromaticity coordinates, dominant wavelength, excitation purity and the distribution in the International Commission on Illumination (CIE) LAB uniform color space were measured. At the same time, the differences of overall chromatism, clarity, chroma, saturation and hue were also calculated and analyzed. PHC patients in different syndrome groups exhibited differences in chromaticity coordinates. The dominant wavelength of QSBS was distinctly different from that of the other 3 syndromes. Excitation purity in the syndromes of LDSD, ADH and DLKY showed gradual increases (Pcolorimetry technology. Different syndromes in PHC exhibit distinct chromatisms of tongue color through the calculation and analysis of chromaticity parameters of CIE, combined with colorimetric system and CIE LAB color space, and these are consistent with the characteristics of clinical tongue color. Applying optical spectrum colorimetry technology to tongue color differentiation has the potential to serve as a reference point in standardizing traditional Chinese medicine syndrome classification in PHC.

  4. A comparison of cell-free placental messenger ribonucleic acid and color Doppler ultrasound for the prediction of placental invasion in patients with placenta accreta.

    Science.gov (United States)

    Naghshineh, Elham; Khorvash, Elahe; Kamali, Sara

    2015-01-01

    The aim of the present study was to comparison between cell-free placental messenger ribonucleic acid (mRNA) and Doppler ultrasound for the prediction of placental invasion in women with placenta accreta. In this cross-sectional study, 50 pregnant women at risk for placenta accreta underwent color Doppler and assessment of cell-free placental mRNA. Real-time reverse-transcription polymerase chain reaction was used for measurement of cell-free placental mRNA in maternal plasma. Based on the findings at cesarean delivery and histological examination, patients were divided into two groups of women with and without placenta accrete. To compare of the mean of mRNA levels between the two groups we used independent t-test and to compare of the mean of age and gestational age at sonography we used Mann-Whitney test. For determination of sensitivity and specificity and the cut-off point of mRNA levels we used the receiver operating characteristic curve. A total of 50 women with a mean age of 30.24 ± 4.905 years entered the study and 12 (24%) patients were diagnosed with placenta accreta. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of Doppler ultrasound were 83.3%, 78.9%, 56% and 94%, respectively. Results of our study showed if we consider a cut-off point equal to 3.325, with sensitivity and specificity of 0.917 and 0.789, respectively and the sensitivity, specificity, PPV and NPV of mRNA with were cut-off point of 3.325 were 91.7%, 78.9%, 57.9% and 96.8%, respectively. Cell-free mRNA is an acceptable, easy made, functional test with sensitivity, specificity, PPV and NPV more than Doppler ultrasound for diagnosis and prediction of incidence of placenta accrete and we recommend the use of cell-free mRNA test for diagnosis of placenta accreta.

  5. Suspended sediment concentration and optical property observations of mixed-turbidity, coastal waters through multispectral ocean color inversion

    Science.gov (United States)

    Multispectral satellite ocean color data from high-turbidity areas of the coastal ocean contain information about the surface concentrations and optical properties of suspended sediments and colored dissolved organic matter (CDOM). Empirical and semi-analytical inversion algorit...

  6. INITIAL FOLLOW-UP OF OPTICAL TRANSIENTS WITH COLORES USING THE BOOTES NETWORK

    Directory of Open Access Journals (Sweden)

    Maria D. Caballero-Garcia

    2015-04-01

    Full Text Available The Burst Observer and Optical Transient Exploring System (BOOTES is a network of telescopes that allows the continuous monitoring of transient astrophysical sources. It was originally devoted to the study of the optical emissions from gamma-raybursts (GRBs that occur in the Universe. In this paper we show the initial results obtained using the spectrograph COLORES (mounted on BOOTES-2, when observing optical transients (OTs of a diverse nature.

  7. Sub-Doppler spectroscopy

    International Nuclear Information System (INIS)

    Hansch, T.W.

    1983-01-01

    This chapter examines Doppler-free saturation spectroscopy, tunable cw sources, and Doppler-free two-photon spectroscopy. Discusses saturation spectroscopy; continuous wave saturation spectroscopy in the ultraviolet; and two-photon spectroscopy of atomic hydrogen 1S-2S. Focuses on Doppler-free laser spectroscopy of gaseous samples. Explains that in saturation spectroscopy, a monochromatic laser beam ''labels'' a group of atoms within a narrow range of axial velocities through excitation or optical pumping, and a Doppler-free spectrum of these selected atoms is observed with a second, counterpropagating beam. Notes that in two-photon spectroscopy it is possible to record Doppler-free spectra without any need for velocity selection by excitation with two counterpropagating laser beams whose first order Doppler shifts cancel

  8. Metasurface optics for full-color computational imaging.

    Science.gov (United States)

    Colburn, Shane; Zhan, Alan; Majumdar, Arka

    2018-02-01

    Conventional imaging systems comprise large and expensive optical components that successively mitigate aberrations. Metasurface optics offers a route to miniaturize imaging systems by replacing bulky components with flat and compact implementations. The diffractive nature of these devices, however, induces severe chromatic aberrations, and current multiwavelength and narrowband achromatic metasurfaces cannot support full visible spectrum imaging (400 to 700 nm). We combine principles of both computational imaging and metasurface optics to build a system with a single metalens of numerical aperture ~0.45, which generates in-focus images under white light illumination. Our metalens exhibits a spectrally invariant point spread function that enables computational reconstruction of captured images with a single digital filter. This work connects computational imaging and metasurface optics and demonstrates the capabilities of combining these disciplines by simultaneously reducing aberrations and downsizing imaging systems using simpler optics.

  9. Optical effects of different colors of artificial gingiva on ceramic crowns.

    Science.gov (United States)

    Wang, Jian; Lin, Jin; Gil, Mindy; Da Silva, John D; Wright, Robert; Ishikawa-Nagai, Shigemi

    2013-08-01

    The interaction between gingival color and the shade of ceramic restorations has never been fully studied. The purpose of this study is to investigate the optical effects of altering artificial gingival color on the ceramic crown shade in the cervical area. Thirty-one all-ceramic crowns of different shades were used in this study with six different artificial gingival colors. Using a spectrophotometer (Crystaleye(®) Olympus, Japan), we measured the shade of crowns in cervical areas with each of six different artificial gingiva. The crown color measured in the presence of pink artificial gingiva (control) was compared with the crown color with five other artificial gingiva. color difference values ΔE* were calculated and compared between the control group and test groups and the correlation of the artificial gingival color with the crown color was also assessed. Significant differences were found in the mean L* and a* values of all-ceramic crowns at the cervical regions in all six gingival color groups (pcolors of artificial gingiva generated clinically detectable shade differences in the cervical region of ceramic crowns. Copyright © 2013. Published by Elsevier Ltd.

  10. SWIM: A Semi-Analytical Ocean Color Inversion Algorithm for Optically Shallow Waters

    Science.gov (United States)

    McKinna, Lachlan I. W.; Werdell, P. Jeremy; Fearns, Peter R. C. S.; Weeks, Scarla J.; Reichstetter, Martina; Franz, Bryan A.; Bailey, Sean W.; Shea, Donald M.; Feldman, Gene C.

    2014-01-01

    In clear shallow waters, light that is transmitted downward through the water column can reflect off the sea floor and thereby influence the water-leaving radiance signal. This effect can confound contemporary ocean color algorithms designed for deep waters where the seafloor has little or no effect on the water-leaving radiance. Thus, inappropriate use of deep water ocean color algorithms in optically shallow regions can lead to inaccurate retrievals of inherent optical properties (IOPs) and therefore have a detrimental impact on IOP-based estimates of marine parameters, including chlorophyll-a and the diffuse attenuation coefficient. In order to improve IOP retrievals in optically shallow regions, a semi-analytical inversion algorithm, the Shallow Water Inversion Model (SWIM), has been developed. Unlike established ocean color algorithms, SWIM considers both the water column depth and the benthic albedo. A radiative transfer study was conducted that demonstrated how SWIM and two contemporary ocean color algorithms, the Generalized Inherent Optical Properties algorithm (GIOP) and Quasi-Analytical Algorithm (QAA), performed in optically deep and shallow scenarios. The results showed that SWIM performed well, whilst both GIOP and QAA showed distinct positive bias in IOP retrievals in optically shallow waters. The SWIM algorithm was also applied to a test region: the Great Barrier Reef, Australia. Using a single test scene and time series data collected by NASA's MODIS-Aqua sensor (2002-2013), a comparison of IOPs retrieved by SWIM, GIOP and QAA was conducted.

  11. Advanced optical design and control of multi-colored SSL system for stage lighting application

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita

    , the light output from the light engine is energy and optically efficient as well as environmentally friendly. The light output stability during the operational time is investigated by using the Monte Carlo simulation and a color sensor is implemented along with the pre‐calibrated lookup table to a feedback...... system in order to provide controlled color and intensity variations within certain limits. By implementing the control mechanism, system‐to‐system calibration is possible. The control mechanism can be generalized to be used in any other SSL system. Instead of using a color sensor, the variation......The thesis deals with a novel LED color mixing light engine which is designed, developed, and subsequently demonstrated by making a prototype of the same, which is experimentally investigated. Further, the design optimization solves the problems of achieving collimated high luminous flux in a color...

  12. Seeing the Light: Optics in Nature, Photography, Color, Vision, and Holography

    Science.gov (United States)

    Falk, David R.; Brill, Dieter R.; Stork, David G.

    1985-11-01

    The most complete and lucid nonmathematical study of light available. Chapters are self-contained, making the book flexible and easy to read. Coverage includes such non-traditional topics as processes of vision and the eye, atmospherical optical phenomena, color perception and illusions, color in nature and in art, Kirilian photography, and holography. Includes experiments that can be carried out with simple equipment. Chapters contain optional advanced sections, and appendixes review the mathematics for quantitative aspects. Illustrated, including a four-color insert.

  13. Simulation of multicomponent light source for optical-electronic system of color analysis objects

    Science.gov (United States)

    Peretiagin, Vladimir S.; Alekhin, Artem A.; Korotaev, Valery V.

    2016-04-01

    Development of lighting technology has led to possibility of using LEDs in the specialized devices for outdoor, industrial (decorative and accent) and domestic lighting. In addition, LEDs and devices based on them are widely used for solving particular problems. For example, the LED devices are widely used for lighting of vegetables and fruit (for their sorting or growing), textile products (for the control of its quality), minerals (for their sorting), etc. Causes of active introduction LED technology in different systems, including optical-electronic devices and systems, are a large choice of emission color and LED structure, that defines the spatial, power, thermal and other parameters. Furthermore, multi-element and color devices of lighting with adjustable illumination properties can be designed and implemented by using LEDs. However, devices based on LEDs require more attention if you want to provide a certain nature of the energy or color distribution at all the work area (area of analysis or observation) or surface of the object. This paper is proposed a method of theoretical modeling of the lighting devices. The authors present the models of RGB multicomponent light source applied to optical-electronic system for the color analysis of mineral objects. The possibility of formation the uniform and homogeneous on energy and color illumination of the work area for this system is presented. Also authors showed how parameters and characteristics of optical radiation receiver (by optical-electronic system) affect on the energy, spatial, spectral and colorimetric properties of a multicomponent light source.

  14. Multimodal reconstruction of microvascular-flow distributions using combined two-photon microscopy and Doppler optical coherence tomography.

    Science.gov (United States)

    Gagnon, Louis; Sakadžić, Sava; Lesage, Fréderic; Mandeville, Emiri T; Fang, Qianqian; Yaseen, Mohammad A; Boas, David A

    2015-01-01

    Computing microvascular cerebral blood flow ([Formula: see text]) in real cortical angiograms is challenging. Here, we investigated whether the use of Doppler optical coherence tomography (DOCT) flow measurements in individual vessel segments can help in reconstructing [Formula: see text] across the entire vasculature of a truncated cortical angiogram. A [Formula: see text] computational framework integrating DOCT measurements is presented. Simulations performed on a synthetic angiogram showed that the addition of DOCT measurements, especially close to large inflowing or outflowing vessels, reduces the impact of pressure boundary conditions and estimated vessel resistances resulting in a more accurate reconstruction of [Formula: see text]. Our technique was then applied to reconstruct microvascular flow distributions in the mouse cortex down to [Formula: see text] by combining two-photon laser scanning microscopy angiography with DOCT.

  15. The measurement of sperm motility by the fibre optic Doppler anemometer as a prediction of bovine fertility

    Science.gov (United States)

    Bullock, J. G.; Ross, D. A.

    The fibre optic Doppler anemometer (FODA) has been used to develop an accurate quantitative method of routinely assessing bull fertility. This method is of importance to the artificial insemination industry because the present qualitative estimation, performed by viewing semen using a microscope, can only set broad limits of quality. Laser light from the FODA was directed into diluted semen samples and the back scattered light was measured. A digital correlator was used to calculate the signal correlation of the back scattered light. The resultant data curves were interpreted in terms of the collective motility and swimming speed of the spermatozoa using a microcomputer. These two parameters are accepted as being indicative of fertility. The accuracy of this method is demonstrated by examination of results obtained in an experiment where enzymes, thought to alter fertility, were added to semen. The effect of the enzymes on the swimming speed and motility was clearly demonstrated.

  16. A High-Speed Optical Diagnostic that uses Interference Filters to Measure Doppler Shifts

    International Nuclear Information System (INIS)

    Paul, S.F.; Cates, C.; Mauel, M.; Maurer, D.; Navratil, G.; Shilov, M.

    2004-01-01

    A high-speed, non-invasive velocity diagnostic has been developed for measuring plasma rotation. The Doppler shift is determined by employing two detectors that view line emission from the identical volume of plasma. Each detector views through an interference filter having a passband that varies linearly with wavelength. One detector views the plasma through a filter whose passband has a negative slope and the second detector views through one with a positive slope. Because each channel views the same volume of plasma, the ratio of the amplitudes is not sensitive to variations in plasma emission. With suitable knowledge of the filter characteristics and the relative gain, the Doppler shift is readily obtained in real time from the ratio of two channels without needing a low throughput spectrometer. The systematic errors--arising from temperature drifts, stability, and frequency response of the detectors and amplifiers, interference filter linearity, and ability to thoroughly homogenize the light from the fiber bundle--can be characterized well enough to obtain velocity data with + or - 1 km/sec with a time resolution of 0.3 msec

  17. DISCOVERING THE MISSING 2.2 < z < 3 QUASARS BY COMBINING OPTICAL VARIABILITY AND OPTICAL/NEAR-INFRARED COLORS

    International Nuclear Information System (INIS)

    Wu Xuebing; Wang Ran; Bian Fuyan; Jiang Linhua; Fan Xiaohui; Schmidt, Kasper B.

    2011-01-01

    The identification of quasars in the redshift range 2.2 < z < 3 is known to be very inefficient because the optical colors of such quasars are indistinguishable from those of stars. Recent studies have proposed using optical variability or near-infrared (near-IR) colors to improve the identification of the missing quasars in this redshift range. Here we present a case study combining both methods. We select a sample of 70 quasar candidates from variables in Sloan Digital Sky Survey (SDSS) Stripe 82, which are non-ultraviolet excess sources and have UKIDSS near-IR public data. They are clearly separated into two parts on the Y - K/g - z color-color diagram, and 59 of them meet or lie close to a newly proposed Y - K/g - z selection criterion for z < 4 quasars. Of these 59 sources, 44 were previously identified as quasars in SDSS DR7, and 35 of them are quasars at 2.2 < z < 3. We present spectroscopic observations of 14 of 15 remaining quasar candidates using the Bok 2.3 m telescope and the MMT 6.5 m telescope, and successfully identify all of them as new quasars at z = 2.36-2.88. We also apply this method to a sample of 643 variable quasar candidates with SDSS-UKIDSS nine-band photometric data selected from 1875 new quasar candidates in SDSS Stripe 82 given by Butler and Bloom based on the time-series selections, and find that 188 of them are probably new quasars with photometric redshifts at 2.2 < z < 3. Our results indicate that the combination of optical variability and optical/near-IR colors is probably the most efficient way to find 2.2 < z < 3 quasars and is very helpful for constructing a complete quasar sample. We discuss its implications for ongoing and upcoming large optical and near-IR sky surveys.

  18. Fabrication of optical multilayer for two-color phase plate in super-resolution microscope.

    Science.gov (United States)

    Iketaki, Yoshinori; Kitagawa, Katsuichi; Hidaka, Kohjiro; Kato, Naoki; Hirabayashi, Akira; Bokor, Nandor

    2014-07-01

    In super-resolution microscopy based on fluorescence depletion, the two-color phase plate (TPP) is an indispensable optical element, which can independently control the phase shifts for two beams of different color, i.e., the pump and erase beams. By controlling a phase shift of the erase beam through the TPP, the erase beam can be modulated into a doughnut shape, while the pump beam maintains the initial Gaussian shape. To obtain a reliable optical multiplayer (ML) for the TPP, we designed a ML with only two optical layers by performing numerical optimization. The measured phase shifts generated by the fabricated ML using interferometry correspond to the design values. The beam profiles in the focal plane are also consistent with theoretical results. Although the fabricated ML consists of only two optical layers, the ML can provide a suitable phase modulation function for the TPP in a practical super-resolution microscope.

  19. Fabrication of optical multilayer for two-color phase plate in super-resolution microscope

    International Nuclear Information System (INIS)

    Iketaki, Yoshinori; Kitagawa, Katsuichi; Hidaka, Kohjiro; Kato, Naoki; Hirabayashi, Akira; Bokor, Nandor

    2014-01-01

    In super-resolution microscopy based on fluorescence depletion, the two-color phase plate (TPP) is an indispensable optical element, which can independently control the phase shifts for two beams of different color, i.e., the pump and erase beams. By controlling a phase shift of the erase beam through the TPP, the erase beam can be modulated into a doughnut shape, while the pump beam maintains the initial Gaussian shape. To obtain a reliable optical multiplayer (ML) for the TPP, we designed a ML with only two optical layers by performing numerical optimization. The measured phase shifts generated by the fabricated ML using interferometry correspond to the design values. The beam profiles in the focal plane are also consistent with theoretical results. Although the fabricated ML consists of only two optical layers, the ML can provide a suitable phase modulation function for the TPP in a practical super-resolution microscope

  20. Theoretical evaluation of measurement uncertainties of two-color pyrometry applied to optical diagnostics

    International Nuclear Information System (INIS)

    Fu Tairan; Cheng Xiaofang; Yang Zangjian

    2008-01-01

    We present a theoretical analysis of two-color pyrometry applied to optical diagnostics. A two-color pyrometer built with a single CCD is advantageous due to the simple system design. We evaluate the possibility and degree of ill-conditionness on the basis of measurement uncertainties for different measurement approaches of this two-color system. We classify measurement approaches. The corresponding ill-conditionness criterion is established. The greater the criterion value is, the worse the ill-conditioned degree of solution is. So, the optimum choice of measurement approach for the two-color system is achieved through intercomparison of the criterion values. Numerical examples are also given to illustrate this point. The theoretical analysis not only provides an effective way of evaluating different measurement approaches, but also may help us to better understand the influences that determine the choices between wavelength/waveband measurements and calibration/noncalibration modes for temperature and soot distribution

  1. Global control of colored moiré pattern in layered optical structures

    Science.gov (United States)

    Li, Kunyang; Zhou, Yangui; Pan, Di; Ma, Xueyan; Ma, Hongqin; Liang, Haowen; Zhou, Jianying

    2018-05-01

    Accurate description of visual effect of colored moiré pattern caused by layered optical structures consisting of gratings and Fresnel lens is proposed in this work. The colored moiré arising from the periodic and quasi-periodic structures is numerically simulated and experimentally verified. It is found that the visibility of moiré pattern generated by refractive optical elements is related to not only the spatial structures of gratings but also the viewing angles. To effectively control the moiré visibility, two constituting gratings are slightly separated. Such scheme is proved to be effective to globally eliminate moiré pattern for displays containing refractive optical films with quasi-periodic structures.

  2. Color Doppler Indices of Orbital Arterial Flow in End-Stage Renal Disease Patients; Are the Changes Related to Chronic Hemodialysis or Chronic Renal Failure?

    International Nuclear Information System (INIS)

    Rokni Yazdi, Hadi; Faraji, Safoura; Ahmadi, Farokhlegha; Shahmirzae, Reza

    2012-01-01

    Endothelial injury is a well-known complication in chronic kidney disease (CKD) and hemodialysis. One of the sites in which early vascular changes may be detected is the retina. Of course, these flow changes may not be detected in ophthalmologic exams, but it seems that color Doppler sonography of retinal arteries may be helpful in these cases. In previous studies on CKD patients who underwent chronic hemodialysis,hemodynamic changes were noted in retinal arteries, but no study has been performed to determine which of the two processes (CKD or chronic hemodialysis) can produce these changes. In this study, we tried to answer this question. Doppler ultrasonography of the orbital vasculature including the ophthalmic artery and the central retinal artery was carried out in 17 patients (34 eyes) with chronic renal failure (CRF) who underwent hemodialysis, 17 patients (34 eyes)with CRF without a history of hemodialysis and 17 normal patients (34 eyes). The peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index were measured excluding hypertensive, diabetic patients and patients with cardiovascular disease. The mean PSV and EDV were lower only in the ophthalmic artery of CRF patients irrespective of the history of hemodialysis (PSV was 35.2 in hemodialysis, 38.8 in CRF and 51.6 in normal patients, P value = 0.001 and EDV was 7.4, 9.4, 11.8, respectively, P value =0.001) with no significant difference in the resistance index of the ophthalmic artery and other parameters [EDV, PSV, Resistance Index (RI)] in the central retinal artery. The mean PSV and DSV in the ophthalmic artery were lower only in the ophthalmic artery of CRF patients regardless of the history of hemodialysis. No significant difference in the resistance index of the ophthalmic artery and other parameters (EDV, PSV) of the central retinal artery were noted between different groups. These findings suggest that microvascular disease and endothelial cell dysfunction of the orbital

  3. Color centers in KCN: ferro-elastic alignment and free optical absorption of phonons

    International Nuclear Information System (INIS)

    Grillo, M.L.N.

    1983-01-01

    Some color centers in KCN pure and KCL or KOH doped are studied. The used tecniques for detection of these color centers were optical absorption and electron paramagnetic resonance (EPR). To obtain this color centers crystals were always exposed to X-rays. With an optical absorption technique, one color center was analysed after X-ray irradiation followed by a suitable photochemical process. Throught the EPR technique the F center and three other centers produced by radiation damage were observed through several KCN solid phases. As in the orthorhombic and ferroelastic phase (temperatures between 168K and 83K), the crystals of KCN present one multidomain structure responsable for strong light scattering on the optical absorption spectra and EPR spectra that does not present the resolved lines formed above 168K, one system of aligned domains was obtained through mechanical stress built specifically to be capable of reducing the number of distinct domain, and this allowed us to observe of partially resolved EPR lines. (Auhtor) [pt

  4. Decomposition of a laser-Doppler spectrum for estimation of speed distribution of particles moving in an optically turbid medium: Monte Carlo validation study

    International Nuclear Information System (INIS)

    Liebert, A; Zolek, N; Maniewski, R

    2006-01-01

    A method for measurement of distribution of speed of particles moving in an optically turbid medium is presented. The technique is based on decomposition of the laser-Doppler spectrum. The theoretical background is shown together with the results of Monte Carlo simulations, which were performed to validate the proposed method. The laser-Doppler spectra were obtained by Monte Carlo simulations for assumed uniform and Gaussian speed distributions of particles moving in the turbid medium. The Doppler shift probability distributions were calculated by Monte Carlo simulations for several anisotropy factors of the medium, assuming the Hanyey-Greenstein phase function. The results of the spectra decomposition show that the calculated speed distribution of moving particles match well the distribution assumed for Monte Carlo simulations. This result was obtained for the spectra simulated in optical conditions, in which the photon is scattered with the Doppler shift not more than once during its travel between the source and detector. Influence of multiple scattering of the photon is analysed and a perspective of spectrum decomposition under such conditions is considered. Potential applications and limitations of the method are discussed

  5. Optical Coronagraphic Spectroscopy of AU Mic: Evidence of Time Variable Colors?

    Science.gov (United States)

    Lomax, Jamie R.; Wisniewski, John P.; Roberge, Aki; Donaldson, Jessica K.; Debes, John H.; Malumuth, Eliot M.; Weinberger, Alycia J.

    2018-02-01

    We present coronagraphic long slit spectra of AU Mic’s debris disk taken with the STIS instrument aboard the Hubble Space Telescope. Our spectra are the first spatially-resolved, scattered light spectra of the system’s disk, which we detect at projected distances between approximately 10 and 45 au. Our spectra cover a wavelength range between 5200 and 10200 Å. We find that the color of AU Mic’s debris disk is bluest at small (12–17 au) projected separations. These results both confirm and quantify the findings qualitatively noted by Krist et al. and are different than IR observations that suggested a uniform blue or gray color as a function of projected separation in this region of the disk. Unlike previous literature, which reported that the color of AU Mic’s disk became increasingly more blue as a function of projected separation beyond ∼30 au, we find the disk’s optical color between 35 and 45 au to be uniformly blue on the southeast side of the disk and decreasingly blue on the northwest side. We note that this apparent change in disk color at larger projected separations coincides with several fast, outward moving “features” that are passing through this region of the southeast side of the disk. We speculate that these phenomenon might be related and that the fast moving features could be changing the localized distribution of sub-micron-sized grains as they pass by, thereby reducing the blue color of the disk in the process. We encourage follow-up optical spectroscopic observations of AU Mic to both confirm this result and search for further modifications of the disk color caused by additional fast moving features propagating through the disk.

  6. Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies.

    Science.gov (United States)

    Vogel, Nicolas; Utech, Stefanie; England, Grant T; Shirman, Tanya; Phillips, Katherine R; Koay, Natalie; Burgess, Ian B; Kolle, Mathias; Weitz, David A; Aizenberg, Joanna

    2015-09-01

    Materials in nature are characterized by structural order over multiple length scales have evolved for maximum performance and multifunctionality, and are often produced by self-assembly processes. A striking example of this design principle is structural coloration, where interference, diffraction, and absorption effects result in vivid colors. Mimicking this emergence of complex effects from simple building blocks is a key challenge for man-made materials. Here, we show that a simple confined self-assembly process leads to a complex hierarchical geometry that displays a variety of optical effects. Colloidal crystallization in an emulsion droplet creates micron-sized superstructures, termed photonic balls. The curvature imposed by the emulsion droplet leads to frustrated crystallization. We observe spherical colloidal crystals with ordered, crystalline layers and a disordered core. This geometry produces multiple optical effects. The ordered layers give rise to structural color from Bragg diffraction with limited angular dependence and unusual transmission due to the curved nature of the individual crystals. The disordered core contributes nonresonant scattering that induces a macroscopically whitish appearance, which we mitigate by incorporating absorbing gold nanoparticles that suppress scattering and macroscopically purify the color. With increasing size of the constituent colloidal particles, grating diffraction effects dominate, which result from order along the crystal's curved surface and induce a vivid polychromatic appearance. The control of multiple optical effects induced by the hierarchical morphology in photonic balls paves the way to use them as building blocks for complex optical assemblies--potentially as more efficient mimics of structural color as it occurs in nature.

  7. Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies

    Science.gov (United States)

    Vogel, Nicolas; Utech, Stefanie; England, Grant T.; Shirman, Tanya; Phillips, Katherine R.; Koay, Natalie; Burgess, Ian B.; Kolle, Mathias; Weitz, David A.; Aizenberg, Joanna

    2015-01-01

    Materials in nature are characterized by structural order over multiple length scales have evolved for maximum performance and multifunctionality, and are often produced by self-assembly processes. A striking example of this design principle is structural coloration, where interference, diffraction, and absorption effects result in vivid colors. Mimicking this emergence of complex effects from simple building blocks is a key challenge for man-made materials. Here, we show that a simple confined self-assembly process leads to a complex hierarchical geometry that displays a variety of optical effects. Colloidal crystallization in an emulsion droplet creates micron-sized superstructures, termed photonic balls. The curvature imposed by the emulsion droplet leads to frustrated crystallization. We observe spherical colloidal crystals with ordered, crystalline layers and a disordered core. This geometry produces multiple optical effects. The ordered layers give rise to structural color from Bragg diffraction with limited angular dependence and unusual transmission due to the curved nature of the individual crystals. The disordered core contributes nonresonant scattering that induces a macroscopically whitish appearance, which we mitigate by incorporating absorbing gold nanoparticles that suppress scattering and macroscopically purify the color. With increasing size of the constituent colloidal particles, grating diffraction effects dominate, which result from order along the crystal’s curved surface and induce a vivid polychromatic appearance. The control of multiple optical effects induced by the hierarchical morphology in photonic balls paves the way to use them as building blocks for complex optical assemblies—potentially as more efficient mimics of structural color as it occurs in nature. PMID:26290583

  8. Influence of optical properties of esthetic brackets (color, translucence, and fluorescence) on visual perception.

    Science.gov (United States)

    Lopes Filho, Hibernon; Maia, Lúcio E G; Araújo, Marcus Vinicius A; Ruellas, Antônio Carlos O

    2012-04-01

    The aims of this study were to evaluate the optical properties of esthetic brackets and determine their influence on visual perception. Eighty esthetic brackets of 16 commercial brands were tested. The color and translucency of the brackets, as well as the color of the maxillary central incisors of 40 subjects, were measured with a spectrophotometer. The fluorescence of the brackets was determined by duly calibrated appraisers. The color differences between the brands of brackets and the teeth were calculated. Data were analyzed by using 1-way analysis of variance; the Scheffé multiple comparison test was used to establish the difference between brands of brackets, (α = 0.05). The color parameters L ∗ a ∗ b ∗ of nontranslucent brackets ranged from 49.4 to 86.0, -1.6 to 3.0, and 1.9 to 14.6, respectively. The direct transmission of light ranged from 0.0% to 38.8% transmittance. No bracket showed fluorescence. The color and translucency, as well as the color difference, of the brackets were influenced by brand (P perception; translucent brackets and the nontranslucent InVu (TP Orthodontics, LaPorte, Ind) brackets were less visually perceptible. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  9. Optical properties of color centers in calcium-stabilized gadolinium gallium garnets

    International Nuclear Information System (INIS)

    Pogatshnik, G.J.; Cain, L.S.; Chen, Y.; Evans, B.D.

    1991-01-01

    The addition of small amounts of calcium during the crystal growth of large-diameter, gadolinium gallium garnet (GGG) crystals creates color centers that absorb in the near-uv region of the spectrum. Ultraviolet and γ-ray irradiation of the crystals produced changes in the intensities of the uv color-center bands along with a broad absorption throughout the visible spectrum. The color center that gives rise to an absorption band at 350 nm serves as a photoionizable donor center so that uv excitation results in a visible coloration of the crystals. The effects of oxidation and reduction treatments on the strength of the color-center bands and on the radiation response of the material were examined. Photoluminescence bands were observed in both reduced GGG crystals as well as crystals that were irradiated with neutrons. Visible coloration is likely to occur during flashlamp pumping of laser rods that utilize large-diameter GGG crystals as the laser host. The changes in the optical properties of the material under uv excitation indicate that the addition of small amounts of calcium to assist in the growth of large-diameter crystals is likely to result in the degradation of laser performance

  10. Ocean Optics Protocols for Satellite Ocean Color Sensor Validation. Revised

    Science.gov (United States)

    Fargion, Giulietta S.; Mueller, James L.

    2000-01-01

    The document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. This document supersedes the earlier version (Mueller and Austin 1995) published as Volume 25 in the SeaWiFS Technical Report Series. This document marks a significant departure from, and improvement on, theformat and content of Mueller and Austin (1995). The authorship of the protocols has been greatly broadened to include experts specializing in some key areas. New chapters have been added to provide detailed and comprehensive protocols for stability monitoring of radiometers using portable sources, abovewater measurements of remote-sensing reflectance, spectral absorption measurements for discrete water samples, HPLC pigment analysis and fluorometric pigment analysis. Protocols were included in Mueller and Austin (1995) for each of these areas, but the new treatment makes significant advances in each topic area. There are also new chapters prescribing protocols for calibration of sun photometers and sky radiance sensors, sun photometer and sky radiance measurements and analysis, and data archival. These topic areas were barely mentioned in Mueller and Austin (1995).

  11. Anatomic and hemodynamic evaluation of renal venous flow in varicocele formation using color Doppler sonography with emphasis on renal vein entrapment syndrome.

    Science.gov (United States)

    Unlu, Murat; Orguc, Sebnem; Serter, Selim; Pekindil, Gokhan; Pabuscu, Yuksel

    2007-01-01

    To investigate the anatomic and hemodynamic properties of testicular venous drainage and its effects on varicocele formation and reflux using color Doppler ultrasound (US) with emphasis on renal vein entrapment syndrome. Upper abdominal and scrotal US examinations of 35 varicocele patients and 35 healthy male subjects were performed in the supine position during rest, during a Valsalva maneuver and in the erect position. The aortomesenteric angle and distance (AMA and AMD, respectively), peak mean velocities (PVs) and diameters of different segments of renal veins, testicular vein diameters and duration of flow inversion were measured. In the varicocele group, the lateral segment of the left renal vein (LRV) had a larger diameter and slower PV, and the medial segment of the LRV had a smaller diameter and faster PV. The diameter of the dominant draining vein correlated with the PV of the medial and lateral segments of the LRV, whereas there was no correlation between the diameter of the dominant draining vein and the diameters of the right renal vein (RRV) and the lateral segment of the LRV or the PV of the RRV. The duration of flow inversion correlated with the diameter and PV of the medial segment of the LRV. No correlation between the diameters and PVs of the RRV and the lateral segment of the LRV was detected. The decreases in the AMA, AMD, diameter of the medial segment of the LRV and PV of the lateral segment of the LRV, and the increases in the PV of the medial segment of the LRV and the diameter of the lateral segment of the LRV in varicocele patients in all positions suggest the entrapment or impingement of the left renal vein between the aorta and the superior mesenteric artery. This has been defined as the "nutcracker phenomenon", which is known to affect varicocele formation.

  12. Optimal combinations for detection of prostate cancer: systematic sextant and laterally directed biopsies versus systematic sextant and color Doppler-targeted biopsies.

    Science.gov (United States)

    Kravchick, Sergey; Cytron, Shmuel; Peled, Ronit; London, Daniel; Sibi, Yosef; Ben-Dor, David

    2004-02-01

    To determine the accuracy of different combinations of biopsies in detecting prostate cancer. The standard sextant protocol for obtaining prostate biopsy underestimates the presence of prostate cancer. Conversely, an increased cancer detection rate has been obtained with additional laterally directed biopsies. The results of the studies dedicated to transrectal color Doppler (CD) sonography have shown that it might detect neoplastic lesions with no corresponding gray-scale abnormality. A total of 120 consecutive patients underwent sextant biopsy with additional biopsy cores taken from the lateral peripheral zone (four to six cores, depending on the prostate volume) and CD-guided biopsy. The sensitivity of laterally directed, CD-guided, and different combinations of biopsies was compared. Various patient, clinical, and pathologic factors were compared, and multivariate analysis was performed to assess the strongest predictor of cancer detection. Cancer was detected in 43 (35.8%) of 120 patients. The combination of sextant biopsy with laterally directed cores gained sensitivity to 56.6% compared with 67.4% obtained in the regimen that combined sextant and CD-guided biopsy. The CD regimen detected cancer in 11 additional patients. However, the differences in the detection rates of these combinations were not statistically significant (P = 0.797). The results of multivariate analysis showed that sextant biopsy and laterally directed cores were the strongest predictors of cancer detection (odds ratio 8.356 versus 49.282; 95% confidence interval 1.698 to 41.114 versus 10.508 to 231.130). The regimen that included sextant and CD-guided biopsy was the most sensitive. However, only standard sextant and laterally directed biopsies were statistically significant predictors of cancer detection on biopsy.

  13. Real-time three-dimensional color doppler evaluation of the flow convergence zone for quantification of mitral regurgitation: Validation experimental animal study and initial clinical experience

    Science.gov (United States)

    Sitges, Marta; Jones, Michael; Shiota, Takahiro; Qin, Jian Xin; Tsujino, Hiroyuki; Bauer, Fabrice; Kim, Yong Jin; Agler, Deborah A.; Cardon, Lisa A.; Zetts, Arthur D.; hide

    2003-01-01

    BACKGROUND: Pitfalls of the flow convergence (FC) method, including 2-dimensional imaging of the 3-dimensional (3D) geometry of the FC surface, can lead to erroneous quantification of mitral regurgitation (MR). This limitation may be mitigated by the use of real-time 3D color Doppler echocardiography (CE). Our objective was to validate a real-time 3D navigation method for MR quantification. METHODS: In 12 sheep with surgically induced chronic MR, 37 different hemodynamic conditions were studied with real-time 3DCE. Using real-time 3D navigation, the radius of the largest hemispherical FC zone was located and measured. MR volume was quantified according to the FC method after observing the shape of FC in 3D space. Aortic and mitral electromagnetic flow probes and meters were balanced against each other to determine reference MR volume. As an initial clinical application study, 22 patients with chronic MR were also studied with this real-time 3DCE-FC method. Left ventricular (LV) outflow tract automated cardiac flow measurement (Toshiba Corp, Tokyo, Japan) and real-time 3D LV stroke volume were used to quantify the reference MR volume (MR volume = 3DLV stroke volume - automated cardiac flow measurement). RESULTS: In the sheep model, a good correlation and agreement was seen between MR volume by real-time 3DCE and electromagnetic (y = 0.77x + 1.48, r = 0.87, P time 3DCE-derived MR volume also showed a good correlation and agreement with the reference method (y = 0.89x - 0.38, r = 0.93, P time 3DCE can capture the entire FC image, permitting geometrical recognition of the FC zone geometry and reliable MR quantification.

  14. Color Doppler imaging of the retrobulbar circulation and plasmatic biomarkers of vascular risk in age-related macular degeneration: A pilot study

    Directory of Open Access Journals (Sweden)

    Fermin Rodrigo

    2018-01-01

    Full Text Available Purpose: To evaluate preliminarily and compare the level of plasmatic biomarkers of vascular risk in patients with and without exudative age-related macular degeneration (ARMD and to relate it to vascular resistance alterations in the ophthalmic artery (OA, central retinal artery (CRA, posterior temporal ciliary artery (PTCA, and posterior nasal ciliary artery (PNCA. Methods: Color Doppler imaging of the OA, CRA, PTCA, and PNCA was performed in 30 eyes of 30 cataract patients (control group as well as in 30 eyes of 30 patients with naive exudative ARMD (study group, measuring the peak systolic velocity, end-diastolic velocity (EDV, and Pourcelot resistive index (RI. Likewise, in both groups, a blood test was performed to determine the plasmatic levels of homocysteine, C-reactive protein (CRP, B12 vitamin, and folic acid. Results: A positive and significant correlation was found between the level of CRP and RI of the OA in the ARMD group (r = 0.498, P = 0.005, with an increased RI in all arteries compared to controls, although differences only reached statistical significance for the PTCA (P = 0.035. Likewise, a significantly lower EDV for the CRA was found in ARMD eyes compared to controls (P = 0.041. In the study group, significantly higher plasmatic levels of homocysteine (P = 0.042 and CRP (P = 0.046 were found. In contrast, no significant differences were found between groups in the levels of folic acid (P = 0.265 and B12 vitamin (P = 0.520. Conclusion: The decrease of the choroidal perfusion related to hyperhomocysteinemia, and increase in the CRP plasmatic levels may play an etiological role on the exudative ARMD. This should be investigated in future studies with larger samples of patients.

  15. Infiltrating a thin or single-layer opal with an atomic vapour: Sub-Doppler signals and crystal optics

    Science.gov (United States)

    Moufarej, Elias; Maurin, Isabelle; Zabkov, Ilya; Laliotis, Athanasios; Ballin, Philippe; Klimov, Vasily; Bloch, Daniel

    2014-10-01

    Artificial thin glass opals can be infiltrated with a resonant alkali-metal vapour, providing novel types of hybrid systems. The reflection at the interface between the substrate and the opal yields a resonant signal, which exhibits sub-Doppler structures in linear spectroscopy for a range of oblique incidences. This result is suspected to originate in an effect of the three-dimensional confinement of the vapour in the opal interstices. It is here extended to a situation where the opal is limited to a few- or even a single-layer opal film, which is a kind of bidimensional grating. We have developed a flexible one-dimensional layered optical model, well suited for a Langmuir-Blodgett opal. Once extended to the case of a resonant infiltration, the model reproduces quick variations of the lineshape with incidence angle or polarization. Alternately, for an opal limited to a single layer of identical spheres, a three-dimensional numerical calculation was developed. It predicts crystalline anisotropy, which is demonstrated through diffraction on an empty opal made of a single layer of polystyrene spheres.

  16. Effects of acetazolamide on the micro- and macro-vascular cerebral hemodynamics: a diffuse optical and transcranial doppler ultrasound study.

    Science.gov (United States)

    Zirak, Peyman; Delgado-Mederos, Raquel; Martí-Fàbregas, Joan; Durduran, Turgut

    2010-11-19

    Acetazolamide (ACZ) was used to stimulate the cerebral vasculature on ten healthy volunteers to assess the cerebral vasomotor reactivity (CVR). We have combined near infrared spectroscopy (NIRS), diffuse correlation spectroscopy (DCS) and transcranial Doppler (TCD) technologies to non-invasively assess CVR in real-time by measuring oxy- and deoxy-hemoglobin concentrations, using NIRS, local cerebral blood flow (CBF), using DCS, and blood flow velocity (CBFV) in the middle cerebral artery, using TCD. Robust and persistent increases in oxy-hemoglobin concentration, CBF and CBFV were observed. A significant agreement was found between macro-vascular (TCD) and micro-vascular (DCS) hemodynamics, between the NIRS and TCD data, and also within NIRS and DCS results. The relative cerebral metabolic rate of oxygen, rCMRO(2), was also determined, and no significant change was observed. Our results showed that the combined diffuse optics-ultrasound technique is viable to follow (CVR) and rCMRO(2) changes in adults, continuously, at the bed-side and in real time.

  17. Characterization of local fluid flow in 3D porous construct characterized by Fourier domain Doppler optical coherence tomography

    Science.gov (United States)

    Bagnaninchi, P. O.; Yang, Y.; El Haj, A.; Hinds, M. T.; Wang, R. K.

    2007-02-01

    In order to achieve functional tissue with the correct biomechanical properties it is critical to stimulate mechanically the cells. Perfusion bioreactor induces fluid shear stress that has been well characterized for two-dimensional culture where both simulation and experimental data are available. However these results can't be directly translated to tissue engineering that makes use of complex three-dimensional porous scaffold. Moreover, stimulated cells produce extensive extra-cellular matrix (ECM) that alter dramatically the micro-architecture of the constructs, changing the local flow dynamic. In this study a Fourier domain Doppler optical coherent tomography (FD-DOCT) system working at 1300nm with a bandwidth of 50nm has been used to determine the local flow rate inside different types of porous scaffolds used in tissue engineering. Local flow rates can then be linearly related, for Newtonian fluid, to the fluid shear stress occurring on the pores wall. Porous chitosan scaffolds (\\fgr 1.5mm x 3mm) with and without a central 250 μm microchannel have been produced by a freeze-drying technique. This techniques allow us to determine the actual shear stress applied to the cells and to optimise the input flow rate consequently, but also to relate the change of the flow distribution to the amount of ECM production allowing the monitoring of tissue formation.

  18. Improved atom number with a dual color magneto—optical trap

    International Nuclear Information System (INIS)

    Cao Qiang; Luo Xin-Yu; Gao Kui-Yi; Wang Xiao-Rui; Wang Ru-Quan; Chen Dong-Min

    2012-01-01

    We demonstrate a novel dual color magneto—optical trap (MOT), which uses two sets of overlapping laser beams to cool and trap 87 Rb atoms. The volume of cold cloud in the dual color MOT is strongly dependent on the frequency difference of the laser beams and can be significantly larger than that in the normal MOT with single frequency MOT beams. Our experiment shows that the dual color MOT has the same loading rate as the normal MOT, but much longer loading time, leading to threefold increase in the number of trapped atoms. This indicates that the larger number is caused by reduced light induced loss. The dual color MOT is very useful in experiments where both high vacuum level and large atom number are required, such as single chamber quantum memory and Bose—Einstein condensation (BEC) experiments. Compared to the popular dark spontaneous-force optical trap (dark SPOT) technique, our approach is technically simpler and more suitable to low power laser systems. (rapid communication)

  19. Observations of the atmospheric tide, mean wind, and sodium nightglow near the mesopause with the magneto- optic Doppler analyzer

    Science.gov (United States)

    Williams, Bifford Preston

    1997-09-01

    In this thesis, I (1) demonstrate a new instrument design that is capable of measuring winds and nightglow; (2) present measurements of the mean winds, tides, and sodium nightglow near the mesopause (ca. 90 km); (3) compare these wind results with those measured by other instruments and results of numerical and empirical models; and (4) compare the nightglow intensity measurements with the predictions of a comprehensive numerical model, to better understand the interaction of the tides with the mesopause-region chemistry. I designed, constructed and operated the Magneto-Optic Doppler Analyzer (MODA). For 1.5 years, Moda observed the sodium nightglow intensity variation and the horizontal wind integrated from ~86-96 km altitude at Niwot Ridge, Colorado (40.0o N, 105.5o W). The observed nightglow intensity showed a significant semidiurnal oscillation, with a 5 hr phase shift in the fall. The mean zonal wind peaked in the summer and winter with a minimum at the equinoxes. The meridional wind was slightly southward or near zero. The semidiurnal tide amplitude peaked in the early summer with a minimum in February. The phases were roughly in quadrature. The measured phase difference between the intensity and zonal wind indicated a seasonal variation of the tide-nightglow interaction. MODA wind results were compared with results from the Urbana Medium-Frequency (MF) Radar, the High Resolution Doppler Imager (HRDI), the empirical Horizontal Wind Model 1993 (HWM93), and the theoretical Global Scale Wave Model (GSWM). The annual variation of the mean winds showed the same pattern amongst the instruments and models. MODA measured the smallest tidal amplitudes, possibly due to longitudinal differences. MODA semidiurnal phases agreed better with HRDI and HWM93 (1-2 hr difference), than with GSWM (~6 hr difference). The calculated semidiurnal sodium nightglow variation from the Thermosphere-Ionosphere-Mesosphere- Electrodynamics General Circulation Model for March shows a

  20. Enhancement of absorption and color contrast in ultra-thin highly absorbing optical coatings

    Science.gov (United States)

    Kats, Mikhail A.; Byrnes, Steven J.; Blanchard, Romain; Kolle, Mathias; Genevet, Patrice; Aizenberg, Joanna; Capasso, Federico

    2013-09-01

    Recently a new class of optical interference coatings was introduced which comprises ultra-thin, highly absorbing dielectric layers on metal substrates. We show that these lossy coatings can be augmented by an additional transparent subwavelength layer. We fabricated a sample comprising a gold substrate, an ultra-thin film of germanium with a thickness gradient, and several alumina films. The experimental reflectivity spectra showed that the additional alumina layer increases the color range that can be obtained, in agreement with calculations. More generally, this transparent layer can be used to enhance optical absorption, protect against erosion, or as a transparent electrode for optoelectronic devices.

  1. Electro-optical and physic-mechanical properties of colored alicyclic polyimide

    Science.gov (United States)

    Kravtsova, V.; Umerzakova, M.; Korobova, N.; Timoshenkov, S.; Timoshenkov, V.; Orlov, S.; Iskakov, R.; Prikhodko, O.

    2016-09-01

    Main optical, thermal and mechanical properties of new compositions based on alicyclic polyimide and active bright red 6C synthetic dye have been studied. It was shown that the transmission ratio of the new material in the region of 400-900 nm and 2.0 wt.% dye concentration was around 60-70%. Thermal, mechanical and electrical properties of new colored compositions were comparable with the properties of original polyimide.

  2. Soft X-ray imaging by optically stimulated luminescence from color centers in lithium fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Bonfigli, F. [ENEA, C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy)], E-mail: bonfigli@frascati.enea.it; Almaviva, S.; Baldacchini, G.; Bollanti, S.; Flora, F.; Lai, A.; Montereali, R.M. [ENEA, C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy); Nichelatti, E. [ENEA, C.R. Casaccia, Via Anguillarese 301, 00060 S.Maria di Galeria (Rome) (Italy); Tomassetti, G.; Ritucci, A.; Reale, L. [Universita de L' Aquila e INFN, Dip. di Fisica, Coppito, L' Aquila (Italy); Faenov, A. Ya.; Pikuz, T.A. [MISDC of VNIIFTRI Mendeleevo, Moscow region, 141570 (Russian Federation); Larciprete, R. [ISC-CNR, Sezione Montelibretti, Via Salaria, Km. 29.3, 00016 Monterotondo Scalo (Rome) (Italy); Gregoratti, L.; Kiskinova, M. [Sincrotrone Trieste, S. S. 14, Km. 163.5, 34012 Basovizza (TS) (Italy)

    2007-07-15

    An innovative X-ray imaging detector based on Optically Stimulated Luminescence from color centers in lithium fluoride is presented. Regular photoluminescent patterns produced on LiF samples by different intense X-ray sources, like synchrotrons, laser plasma sources and a capillary discharge laser have been investigated by a Confocal Laser Scanning Microscope. The use of a LiF-based imaging plate for X-ray microscopy is also discussed showing microradiographies of small animals.

  3. Two-color mid-infrared spectroscopy of optically doped semiconductors

    International Nuclear Information System (INIS)

    Forcales, M.; Klik, M.A.J.; Vinh, N.Q.; Phillips, J.; Wells, J-P.R.; Gregorkiewicz, T.

    2003-01-01

    Optical doping is an attractive method to tailor photonic properties of semiconductor matrices for development of solid-state electroluminescent structures. For practical applications, thermal stability of emission obtained from these materials is required. Thermal processes can be conveniently investigated by two-color spectroscopy in the visible and the mid-infrared. Free-electron laser is a versatile high-brilliance source of radiation in the latter spectral range. In this contribution, we briefly review some of the results obtained recently by the two-color spectroscopy with a free-electron laser in different semiconductors optically doped with rare earth and transition metal ions. Effects leading to both enhancement and quenching of emission from optical dopants will be presented. For InP:Yb, Si:Er, and Si:Cu activation of particular optically induced non-radiative recombination paths will be shown. For Si:Er and Si:Ag, observation of a low temperature optical memory effect will be reported

  4. Color electron microprobe cathodoluminescence of Bishunpur meteorite compared with the traditional optical microscopy method

    Directory of Open Access Journals (Sweden)

    Amanda Araujo Tosi

    Full Text Available Abstract Cathodoluminescence (CL imaging is an outstanding method for sub classification of Unequilibrated Ordinary Chondrites (UOC - petrological type 3. CL can be obtained by several electron beam apparatuses. The traditional method uses an electron gun coupled to an optical microscope (OM. Although many scanning electron microscopes (SEM and electron microprobes (EPMA have been equipped with a cathodoluminescence, this technique was not fully explored. Images obtained by the two methods differ due to a different kind of signal acquisition. While in the CL-OM optical photography true colors are obtained, in the CL-EPMA the results are grayscale monochromatic electronic signals. L-RGB filters were used in the CL-EPMA analysis in order to obtain color data. The aim of this work is to compare cathodoluminescence data obtained from both techniques, optical microscope and electron microprobe, on the Bishunpur meteorite classified as LL 3.1 chondrite. The present study allows concluding that 20 KeV and 7 nA is the best analytical condition at EPMA in order to test the equivalence between CL-EPMA and CL-OM colour results. Moreover, the color index revealed to be a method for aiding the study of the thermal metamorphism, but it is not definitive for the meteorite classification.

  5. Field programmable gate array-based real-time optical Doppler tomography system for in vivo imaging of cardiac dynamics in the chick embryo

    DEFF Research Database (Denmark)

    Thrane, Lars; Larsen, Henning Engelbrecht; Norozi, Kambiz

    2009-01-01

    efficient and compact implementation by combining the conversion to an analytic signal with a pulse shaping function without the need for extra resources as compared to the Hilbert transform method. The conversion of the analytic signal to amplitude and phase is done by use of the coordinate rotation......We demonstrate a field programmable gate-array-based real-time optical Doppler tomography system. A complex-valued bandpass filter is used for the first time in optical coherence tomography signal processing to create the analytic signal. This method simplifies the filter design, and allows...

  6. Layer-by-layer assembly of multicolored semiconductor quantum dots towards efficient blue, green, red and full color optical films

    International Nuclear Information System (INIS)

    Zhang Jun; Li Qian; Di Xiaowei; Liu Zhiliang; Xu Gang

    2008-01-01

    Multicolored semiconductor quantum dots have shown great promise for construction of miniaturized light-emitting diodes with compact size, low weight and cost, and high luminescent efficiency. The unique size-dependent luminescent property of quantum dots offers the feasibility of constructing single-color or full-color output light-emitting diodes with one type of material. In this paper, we have demonstrated the facile fabrication of blue-, green-, red- and full-color-emitting semiconductor quantum dot optical films via a layer-by-layer assembly technique. The optical films were constructed by alternative deposition of different colored quantum dots with a series of oppositely charged species, in particular, the new use of cationic starch on glass substrates. Semiconductor ZnSe quantum dots exhibiting blue emission were deposited for fabrication of blue-emitting optical films, while semiconductor CdTe quantum dots with green and red emission were utilized for construction of green- and red-emitting optical films. The assembly of integrated blue, green and red semiconductor quantum dots resulted in full-color-emitting optical films. The luminescent optical films showed very bright emitting colors under UV irradiation, and displayed dense, smooth and efficient luminous features, showing brighter luminescence in comparison with their corresponding quantum dot aqueous colloid solutions. The assembled optical films provide the prospect of miniaturized light-emitting-diode applications.

  7. First ground-based optical analysis of Hβ Doppler profiles close to local noon in the cusp

    Directory of Open Access Journals (Sweden)

    S. C. Robertson

    2006-10-01

    Full Text Available Observations of hydrogen emissions along the magnetic zenith at Longyearbyen (78.2 N, 15.8 E geographic are used to investigate the energy and source of protons precipitating into the high latitude region. During the hours around local solar noon (11:00 UT, measurements of the hydrogen Balmer β line are severely affected by sunlight, such that most data until now have been disregarded during these times. Here we use a simple technique to subtract sunlight contamination from such spectral data. An example is shown in which the removal of twilight contamination reveals a brightening of Hβ aurora over Svalbard on 27 November 2000 between 08:00 UT and 10:00 UT, which is centred on magnetic noon (08:48 UT. These data were measured by the High Throughput Imaging Echelle Spectrograph (HiTIES, one instrument on the Southampton-UCL Spectrographic Imaging Facility (SIF. Data from the IMAGE satellite confirms the location of a cusp "spot" over Svalbard at the time of the ground-based measurements, which moved in response to changes in the IMF conditions. A coincident pass of the DMSP F12 satellite provided input spectra for modelling studies of the Hβ profiles, which confirm that the method for removing the twilight contamination is robust. The results described here are the first ground-based optical measurements of Hβ Doppler profiles from the cusp region close to local solar noon, when scattered sunlight swamps the raw data.

  8. In situ monitoring of localized shear stress and fluid flow within developing tissue constructs by Doppler optical coherence tomography

    Science.gov (United States)

    Jia, Yali; Bagnaninchi, Pierre O.; Wang, Ruikang K.

    2008-02-01

    Mechanical stimuli can be introduced to three dimensional (3D) cell cultures by use of perfusion bioreactor. Especially in musculoskeletal tissues, shear stress caused by fluid flow generally increase extra-cellular matrix (ECM) production and cell proliferation. The relationship between the shear stress and the tissue development in situ is complicated because of the non-uniform pore distribution within the cell-seeded scaffold. In this study, we firstly demonstrated that Doppler optical coherence tomography (DOCT) is capable of monitoring localized fluid flow and shear stress in the complex porous scaffold by examining their variation trends at perfusion rate of 5, 8, 10 and 12 ml/hr. Then, we developed the 3D porous cellular constructs, cell-seeded chitosan scaffolds monitored during several days by DOCT. The fiber based fourier domain DOCT employed a 1300 nm superluminescent diode with a bandwidth of 52 nm and a xyz resolution of 20×20×15 μm in free space. This setup allowed us not only to assess the cell growth and ECM deposition by observing their different scattering behaviors but also to further investigate how the cell attachment and ECM production has the effect on the flow shear stress and the relationship between flow rate and shear stress in the developing tissue construct. The possibility to monitor continuously the constructs under perfusion will easily indicate the effect of flow rate or shear stress on the cell viability and cell proliferation, and then discriminate the perfusion parameters affecting the pre-tissue formation rate growth.

  9. Quantitative analysis of aortic regurgitation: real-time 3-dimensional and 2-dimensional color Doppler echocardiographic method--a clinical and a chronic animal study

    Science.gov (United States)

    Shiota, Takahiro; Jones, Michael; Tsujino, Hiroyuki; Qin, Jian Xin; Zetts, Arthur D.; Greenberg, Neil L.; Cardon, Lisa A.; Panza, Julio A.; Thomas, James D.

    2002-01-01

    BACKGROUND: For evaluating patients with aortic regurgitation (AR), regurgitant volumes, left ventricular (LV) stroke volumes (SV), and absolute LV volumes are valuable indices. AIM: The aim of this study was to validate the combination of real-time 3-dimensional echocardiography (3DE) and semiautomated digital color Doppler cardiac flow measurement (ACM) for quantifying absolute LV volumes, LVSV, and AR volumes using an animal model of chronic AR and to investigate its clinical applicability. METHODS: In 8 sheep, a total of 26 hemodynamic states were obtained pharmacologically 20 weeks after the aortic valve noncoronary (n = 4) or right coronary (n = 4) leaflet was incised to produce AR. Reference standard LVSV and AR volume were determined using the electromagnetic flow method (EM). Simultaneous epicardial real-time 3DE studies were performed to obtain LV end-diastolic volumes (LVEDV), end-systolic volumes (LVESV), and LVSV by subtracting LVESV from LVEDV. Simultaneous ACM was performed to obtain LVSV and transmitral flows; AR volume was calculated by subtracting transmitral flow volume from LVSV. In a total of 19 patients with AR, real-time 3DE and ACM were used to obtain LVSVs and these were compared with each other. RESULTS: A strong relationship was found between LVSV derived from EM and those from the real-time 3DE (r = 0.93, P <.001, mean difference (3D - EM) = -1.0 +/- 9.8 mL). A good relationship between LVSV and AR volumes derived from EM and those by ACM was found (r = 0.88, P <.001). A good relationship between LVSV derived from real-time 3DE and that from ACM was observed (r = 0.73, P <.01, mean difference = 2.5 +/- 7.9 mL). In patients, a good relationship between LVSV obtained by real-time 3DE and ACM was found (r = 0.90, P <.001, mean difference = 0.6 +/- 9.8 mL). CONCLUSION: The combination of ACM and real-time 3DE for quantifying LV volumes, LVSV, and AR volumes was validated by the chronic animal study and was shown to be clinically applicable.

  10. Comparison of findings of spontaneous splenorenal shunt in color Doppler sonography with multislice CT scan (64 slices) in liver transplant candidates

    Energy Technology Data Exchange (ETDEWEB)

    Bagheri, Mohammadhadi, E-mail: Bagherimh@gmail.com [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Hajati, Azadeh, E-mail: azadeh.hajati@gmail.com [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Hosseini, Mohammadkazem, E-mail: hosseiniaslm@sums.ac.ir [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of); Ostad, Seyed Pouria, E-mail: Pouria.Ostad@gmail.com [Department of Radiology, Shiraz University of Medical Sciences, Namazi Hospital, Shiraz (Iran, Islamic Republic of)

    2012-09-15

    Background: Liver transplantation is the only definite treatment for end stage liver disease and it has high costs for the medical system so decreasing its complication and increasing its effectiveness is crucial. One of the factors that affect liver transplantation is the presence of spontaneous splenorenal shunt. Its diagnosis is mainly overlooked in pre-liver transplant patients. Main modality for its diagnosis is multislice CT scan however this is more expensive than sonography. Also, it exposes the patients to ionizing radiation. Considering the advantages of color Doppler ultrasound, studies to determine the sensitivity and specificity for detection of spontaneous splenorenal shunt is essential. Materials and methods: In our study 70 cirrhotic patients who were referred by liver transplant surgeons for evaluation of abdomen by CT and sonograhy were assessed for presence of spontaneous splenorenal shunt, left adrenal varix and left renal vein diameter and velocity and sensitivity and specificity of both modalities were checked. Patients in whom left renal vein could not evaluated by sonography and patients with splenectomy and nutcracker syndrome were excluded. Results: In the point of 10 mm diameter of left renal vein in CT scan there was 78.6% sensitivity and 67.9% specificity for the presence of spontaneous splenorenal shunt. Left adrenal varix in CT had sensitivity of 71.4%, specificity of 100%, and positive predictive value of 100% and negative predictive value of 70% and varix below spleen in CT had sensitivity of 54.8%, specificity of 96.4%, and positive predictive value of 95.8% and negative predictive value of 58.7% for the presence of spontaneous splenorenal shunt. In the point of 8 mm diameter of left renal vein in sonography there was 66.7% sensitivity and 85.7% specificity for the presence of spontaneous splenorenal shunt. For the velocity of more than 35 cm/s of left renal vein in sonography there was 61.9% sensitivity and 82.1% specificity for

  11. OPTICAL-NEAR-INFRARED COLOR GRADIENTS AND MERGING HISTORY OF ELLIPTICAL GALAXIES

    International Nuclear Information System (INIS)

    Kim, Duho; Im, Myungshin

    2013-01-01

    It has been suggested that merging plays an important role in the formation and the evolution of elliptical galaxies. While gas dissipation by star formation is believed to steepen metallicity and color gradients of the merger products, mixing of stars through dissipation-less merging (dry merging) is believed to flatten them. In order to understand the past merging history of elliptical galaxies, we studied the optical-near-infrared (NIR) color gradients of 204 elliptical galaxies. These galaxies are selected from the overlap region of the Sloan Digital Sky Survey (SDSS) Stripe 82 and the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). The use of optical and NIR data (g, r, and K) provides large wavelength baselines, and breaks the age-metallicity degeneracy, allowing us to derive age and metallicity gradients. The use of the deep SDSS Stripe 82 images makes it possible for us to examine how the color/age/metallicity gradients are related to merging features. We find that the optical-NIR color and the age/metallicity gradients of elliptical galaxies with tidal features are consistent with those of relaxed ellipticals, suggesting that the two populations underwent a similar merging history on average and that mixing of stars was more or less completed before the tidal features disappeared. Elliptical galaxies with dust features have steeper color gradients than the other two types, even after masking out dust features during the analysis, which can be due to a process involving wet merging. More importantly, we find that the scatter in the color/age/metallicity gradients of the relaxed and merging feature types decreases as their luminosities (or masses) increase at M > 10 11.4 M ☉ but stays large at lower luminosities. Mean metallicity gradients appear nearly constant over the explored mass range, but a possible flattening is observed at the massive end. According to our toy model that predicts how the distribution of metallicity gradients

  12. Is the measurement of inferior thyroid artery blood flow velocity by color-flow Doppler ultrasonography useful for differential diagnosis between gestational transient thyrotoxicosis and Graves' disease? A prospective study.

    Science.gov (United States)

    Zuhur, Sayid Shafi; Ozel, Alper; Velet, Selvinaz; Buğdacı, Mehmet Sait; Cil, Esra; Altuntas, Yüksel

    2012-01-01

    To determine the role of peak systolic velocity, end-diastolic velocity and resistance indices of both the right and left inferior thyroid arteries measured by color-flow Doppler ultrasonography for a differential diagnosis between gestational transient thyrotoxicosis and Graves' disease during pregnancy. The right and left inferior thyroid artery-peak systolic velocity, end-diastolic velocity and resistance indices of 96 patients with thyrotoxicosis (41 with gestational transient thyrotoxicosis, 31 age-matched pregnant patients with Graves' disease and 24 age- and sex-matched non-pregnant patients with Graves' disease) and 25 age and sex-matched healthy euthyroid subjects were assessed with color-flow Doppler ultrasonography. The right and left inferior thyroid artery-peak systolic and end-diastolic velocities in patients with gestational transient thyrotoxicosis were found to be significantly lower than those of pregnant patients with Graves' disease and higher than those of healthy euthyroid subjects. However, the right and left inferior thyroid artery peak systolic and end-diastolic velocities in pregnant patients with Graves' disease were significantly lower than those of non-pregnant patients with Graves' disease. The right and left inferior thyroid artery peak systolic and end-diastolic velocities were positively correlated with TSH-receptor antibody levels. We found an overlap between the inferior thyroid artery-blood flow velocities in a considerable number of patients with gestational transient thyrotoxicosis and pregnant patients with Graves' disease. This study suggests that the measurement of inferior thyroid artery-blood flow velocities with color-flow Doppler ultrasonography does not have sufficient sensitivity and specificity to be recommended as an initial diagnostic test for a differential diagnosis between gestational transient thyrotoxicosis and Graves' disease during pregnancy.

  13. Study of hemodynamics of retroocular vascular by color Doppler ultrasound in diabetes%彩色多普勒超声对糖尿病眼球后血管血流动力学研究

    Institute of Scientific and Technical Information of China (English)

    雷震; 张梅; 李加平; 龙劲松

    2011-01-01

    目的:通过彩色多普勒超声观察糖尿病眼球后血管的血流动力学,研究其诊断价值.方法:共用彩色多普勒超声检查了正常人眼球、糖尿病视网膜病变(diabetic retinopathy,DR)及有糖尿病但无糖尿病视网膜病变(non-diabetic retinopathy,NDR)眼球的球后血管并与荧光素眼底血管造影及检眼镜对比.结果:随着DR的进展,糖尿病患者眼球后血管血流动力学改变的趋势是眼球后动脉的血流速度下降,阻力升高;球后静脉流速增高伴搏动性增强.结论:彩色多普勒超声技术为定量评价DR,判断其预后提供了重要的参考价值.%Objective: To observe the hemodynamic changes of retroocular and evaluate the diagnostic valuation of color Doppler ultraqound in diabetes. Methods: Retroocular hemodynamics were measured in normal and diabetic retinopathy (DR) and non-diabetic retinopathy (NDR) on color Doppler flow imagining and compared with fundus fluorescein angiography (FFA) and Ophthalmoscope. Results: In the progress of DR, the flow's decrease and the resistance's mcrease of retroocular artery were detected in this research, the increase of flow and pulsatility index of retroocular vein were observed too.Conclusion: Color Doppler ultrasound is of important reference value for not only prognosis but also quantitative analysis of diabetic retinopathy.

  14. Improving Coastal Ocean Color Validation Capabilities through Application of Inherent Optical Properties (IOPs)

    Science.gov (United States)

    Mannino, Antonio

    2008-01-01

    Understanding how the different components of seawater alter the path of incident sunlight through scattering and absorption is essential to using remotely sensed ocean color observations effectively. This is particularly apropos in coastal waters where the different optically significant components (phytoplankton, detrital material, inorganic minerals, etc.) vary widely in concentration, often independently from one another. Inherent Optical Properties (IOPs) form the link between these biogeochemical constituents and the Apparent Optical Properties (AOPs). understanding this interrelationship is at the heart of successfully carrying out inversions of satellite-measured radiance to biogeochemical properties. While sufficient covariation of seawater constituents in case I waters typically allows empirical algorithms connecting AOPs and biogeochemical parameters to behave well, these empirical algorithms normally do not hold for case I1 regimes (Carder et al. 2003). Validation in the context of ocean color remote sensing refers to in-situ measurements used to verify or characterize algorithm products or any assumption used as input to an algorithm. In this project, validation capabilities are considered those measurement capabilities, techniques, methods, models, etc. that allow effective validation. Enhancing current validation capabilities by incorporating state-of-the-art IOP measurements and optical models is the purpose of this work. Involved in this pursuit is improving core IOP measurement capabilities (spectral, angular, spatio-temporal resolutions), improving our understanding of the behavior of analytical AOP-IOP approximations in complex coastal waters, and improving the spatial and temporal resolution of biogeochemical data for validation by applying biogeochemical-IOP inversion models so that these parameters can be computed from real-time IOP sensors with high sampling rates. Research cruises supported by this project provides for collection and

  15. Freeform étendue-preserving optics for light and color mixing

    Science.gov (United States)

    Sorgato, Simone; Mohedano, Rubén.; Chaves, Julio; Cvetkovic, Aleksandra; Hernández, Maikel; Benítez, Pablo; Miñano, Juan C.; Thienpont, Hugo; Duerr, Fabian

    2015-09-01

    Today's SSL illumination market shows a clear trend towards high flux packages with higher efficiency and higher CRI, realized by means of multiple color chips and phosphors. Such light sources require the optics to provide both near- and far-field color mixing. This design problem is particularly challenging for collimated luminaries, since traditional diffusers cannot be employed without enlarging the exit aperture and reducing brightness (so increasing étendue). Furthermore, diffusers compromise the light output ratio (efficiency) of the lamps to which they are applied. A solution, based on Köhler integration, consisting of a spherical cap comprising spherical microlenses on both its interior and exterior sides was presented in 2012. When placed on top of an inhomogeneous multichip Lambertian LED, this so-called Shell-Mixer creates a homogeneous (both spatially and angularly) virtual source, also Lambertian, where the images of the chips merge. The virtual source is located at the same position with essentially the same size of the original source. The diameter of this optics was 3 times that of the chip-array footprint. In this work, we present a new version of the Shell-Mixer, based on the Edge Ray Principle, where neither the overall shape of the cap nor the surfaces of the lenses are constrained to spheres or rotational Cartesian ovals. This new Shell- Mixer is freeform, only twice as large as the original chip-array and equals the original model in terms of brightness, color uniformity and efficiency.

  16. Remote sensing estimation of colored dissolved organic matter (CDOM) in optically shallow waters

    Science.gov (United States)

    Li, Jiwei; Yu, Qian; Tian, Yong Q.; Becker, Brian L.

    2017-06-01

    It is not well understood how bottom reflectance of optically shallow waters affects the algorithm performance of colored dissolved organic matters (CDOM) retrieval. This study proposes a new algorithm that considers bottom reflectance in estimating CDOM absorption from optically shallow inland or coastal waters. The field sampling was conducted during four research cruises within the Saginaw River, Kawkawlin River and Saginaw Bay of Lake Huron. A stratified field sampling campaign collected water samples, determined the depth at each sampling location and measured optical properties. The sampled CDOM absorption at 440 nm broadly ranged from 0.12 to 8.46 m-1. Field sample analysis revealed that bottom reflectance does significantly change water apparent optical properties. We developed a CDOM retrieval algorithm (Shallow water Bio-Optical Properties algorithm, SBOP) that effectively reduces uncertainty by considering bottom reflectance in shallow waters. By incorporating the bottom contribution in upwelling radiances, the SBOP algorithm was able to explain 74% of the variance of CDOM values (RMSE = 0.22 and R2 = 0.74). The bottom effect index (BEI) was introduced to efficiently separate optically shallow and optically deep waters. Based on the BEI, an adaptive approach was proposed that references the amount of bottom effect in order to identify the most suitable algorithm (optically shallow water algorithm [SBOP] or optically deep water algorithm [QAA-CDOM]) to improve CDOM estimation (RMSE = 0.22 and R2 = 0.81). Our results potentially help to advance the capability of remote sensing in monitoring carbon pools at the land-water interface.

  17. Comprasion of ovarian stromal blood flow measured by color Doppler ultrasonography in polycystic ovary syndrome patients and healthy women with ultrasonographic evidence of polycystic.

    Science.gov (United States)

    Ozdemir, Ozhan; Sari, Mustafa Erkan; Kalkan, Dilek; Koc, Esra Meltem; Ozdemir, Seyda; Atalay, Cemal Resat

    2015-04-01

    To compare ovarian stromal artery blood flows measured by Doppler ultrasonography of polycystic ovary syndrome (PCOS) patients and healthy women with polycystic ovarian image in ultrasonography. Forty-two patients diagnosed with PCOS according to the criteria of 2003 Rotterdam Concencus Conferance on PCOS and 38 healthy volunteers with polycystic ovarian image in ultrasonography were included in the study. Ovarian volumes and ovarian stromal artery blood flows were measured by 3-dimensional (3-D) ultrasonography and Doppler ultrasonography in all patients. In patients with PCOS, ovarian stromal artery pulsatility index (PI) and resistivity index (RI) were found significantly different from healthy women with polycystic ovarian image in ultrasonography (p ovarian volumes were found significantly higher in patients with PCOS (p ovarian volumes and ovarian stromal artery resistivity indices. Ovarian stromal artery Doppler examination could have an importance to explain the pathophysiology of PCOS, but there are few publications in the literature about PCOS and the details of ovarian stromal artery Doppler parameters in patients with polycystic ovarian image only. We conclude that Doppler ultrasonography findings of PCOS patients might be helpful in understanding the clinical follow-up and etiology of the disease.

  18. Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4, Volume IV: Inherent Optical Properties: Instruments, Characterizations, Field Measurements and Data Analysis Protocols

    Science.gov (United States)

    Mueller, J. L.; Fargion, G. S.; McClain, C. R. (Editor); Pegau, S.; Zanefeld, J. R. V.; Mitchell, B. G.; Kahru, M.; Wieland, J.; Stramska, M.

    2003-01-01

    This document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparision and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. The document is organized into 6 separate volumes as Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4. Volume I: Introduction, Background, and Conventions; Volume II: Instrument Specifications, Characterization and Calibration; Volume III: Radiometric Measurements and Data Analysis Methods; Volume IV: Inherent Optical Properties: Instruments, Characterization, Field Measurements and Data Analysis Protocols; Volume V: Biogeochemical and Bio-Optical Measurements and Data Analysis Methods; Volume VI: Special Topics in Ocean Optics Protocols and Appendices. The earlier version of Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 3 is entirely superseded by the six volumes of Revision 4 listed above.

  19. Efficient color mixing through étendue conservation using freeform optics

    Science.gov (United States)

    Sorgato, Simone; Mohedano, Rubén.; Chaves, Julio; Cvetkovic, Aleksandra; Hernández, Maikel; Benitez, Pablo; Miñano, Juan C.; Thienpont, Hugo; Duerr, Fabian

    2015-08-01

    Today's SSL illumination market shows a clear trend to high flux packages with higher efficiency and higher CRI, realized by means of multiple color chips and phosphors. Such light sources require the optics to provide both near- and far-field color mixing. This design problem is particularly challenging for collimated luminaries, since traditional diffusers cannot be employed without enlarging the exit aperture and reducing brightness. Furthermore, diffusers compromise the light output ratio (efficiency) of the lamps to which they are applied. A solution, based on Köhler integration, consisting of a spherical cap comprising spherical microlenses on both its interior and exterior sides was presented in 2012. The diameter of this so-called Shell-Mixer was 3 times that of the chip array footprint. A new version of the Shell-Mixer, based on the Edge Ray Principle and conservation of etendue, where neither the outer shape of the cap nor the surfaces of the lenses are constrained to spheres or 2D Cartesian ovals will be shown in this work. The new shell is freeform, only twice as large as the original chip-array and equals the original model in terms of color uniformity, brightness and efficiency.

  20. Ultrasonography and color Doppler in juvenile idiopathic arthritis: diagnosis and follow-up of ultrasound-guided steroid injection in the ankle region. A descriptive interventional study

    DEFF Research Database (Denmark)

    Laurell, Louise; Court-Payen, Michel; Nielsen, Susan

    2011-01-01

    The ankle region is frequently involved in juvenile idiopathic arthritis (JIA) but difficult to examine clinically due to its anatomical complexity. The aim of the study was to evaluate the role of ultrasonography (US) of the ankle and midfoot (ankle region) in JIA. Doppler-US detected synovial h...

  1. A comparison of cell-free placental messenger ribonucleic acid and color Doppler ultrasound for the prediction of placental invasion in patients with placenta accreta

    Directory of Open Access Journals (Sweden)

    Elham Naghshineh

    2015-01-01

    Conclusions: Cell-free mRNA is an acceptable, easy made, functional test with sensitivity, specificity, PPV and NPV more than Doppler ultrasound for diagnosis and prediction of incidence of placenta accrete and we recommend the use of cell-free mRNA test for diagnosis of placenta accreta.

  2. Space grating optical structure of the retina and RGB-color vision.

    Science.gov (United States)

    Lauinger, Norbert

    2017-02-01

    Diffraction of light at the spatial cellular phase grating outer nuclear layer of the retina could produce Fresnel near-field interferences in three RGB diffraction orders accessible to photoreceptors (cones/rods). At perpendicular light incidence the wavelengths of the RGB diffraction orders in photopic vision-a fundamental R-wave with two G+B-harmonics-correspond to the peak wavelengths of the spectral brightness sensitivity curves of the cones at 559 nmR, 537 nmG, and 447 nmB. In scotopic vision the R+G diffraction orders optically fuse at 512 nm, the peak value of the rod's spectral brightness sensitivity curve. The diffractive-optical transmission system with sender (resonator), space waves, and receiver antennae converts the spectral light components involved in imaging into RGB space. The colors seen at objects are diffractive-optical products in the eye, as the German philosopher A. Schopenhauer predicted. They are second related to the overall illumination in object space. The RGB transmission system is the missing link optically managing the spectral tuning of the RGB photopigments.

  3. Multifocus microscopy with precise color multi-phase diffractive optics applied in functional neuronal imaging.

    Science.gov (United States)

    Abrahamsson, Sara; Ilic, Rob; Wisniewski, Jan; Mehl, Brian; Yu, Liya; Chen, Lei; Davanco, Marcelo; Oudjedi, Laura; Fiche, Jean-Bernard; Hajj, Bassam; Jin, Xin; Pulupa, Joan; Cho, Christine; Mir, Mustafa; El Beheiry, Mohamed; Darzacq, Xavier; Nollmann, Marcelo; Dahan, Maxime; Wu, Carl; Lionnet, Timothée; Liddle, J Alexander; Bargmann, Cornelia I

    2016-03-01

    Multifocus microscopy (MFM) allows high-resolution instantaneous three-dimensional (3D) imaging and has been applied to study biological specimens ranging from single molecules inside cells nuclei to entire embryos. We here describe pattern designs and nanofabrication methods for diffractive optics that optimize the light-efficiency of the central optical component of MFM: the diffractive multifocus grating (MFG). We also implement a "precise color" MFM layout with MFGs tailored to individual fluorophores in separate optical arms. The reported advancements enable faster and brighter volumetric time-lapse imaging of biological samples. In live microscopy applications, photon budget is a critical parameter and light-efficiency must be optimized to obtain the fastest possible frame rate while minimizing photodamage. We provide comprehensive descriptions and code for designing diffractive optical devices, and a detailed methods description for nanofabrication of devices. Theoretical efficiencies of reported designs is ≈90% and we have obtained efficiencies of > 80% in MFGs of our own manufacture. We demonstrate the performance of a multi-phase MFG in 3D functional neuronal imaging in living C. elegans.

  4. THE OPTICAL VARIABILITY OF SDSS QUASARS FROM MULTI-EPOCH SPECTROSCOPY. II. COLOR VARIATION

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hengxiao; Gu, Minfeng, E-mail: hxguo@shao.ac.cn, E-mail: gumf@shao.ac.cn [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China)

    2016-05-01

    We investigated the optical/ultraviolet (UV) color variations for a sample of 2169 quasars based on multi-epoch spectroscopy in the Sloan Digital Sky Survey data releases seven (DR7) and nine (DR9). To correct the systematic difference between DR7 and DR9 due to the different instrumental setup, we produced a correction spectrum by using a sample of F-stars observed in both DR7 and DR9. The correction spectrum was then applied to quasars when comparing the spectra of DR7 with DR9. In each object, the color variation was explored by comparing the spectral index of the continuum power-law fit on the brightest spectrum with the faintest one, and also by the shape of their difference spectrum. In 1876 quasars with consistent color variations from two methods, we found that most sources (1755, ∼94%) show the bluer-when-brighter (BWB) trend, and the redder-when-brighter (RWB) trend is detected in only 121 objects (∼6%). The common BWB trend is supported by the composite spectrum constructed from bright spectra, which is bluer than that from faint spectra, and also by the blue composite difference spectrum. The correction spectrum is proven to be highly reliable by comparing the composite spectrum from corrected DR9 and original DR7 spectra. Assuming that the optical/UV variability is triggered by fluctuations, the RWB trend can likely be explained if the fluctuations occur first in the outer disk region, and the inner disk region has not yet fully responded when the fluctuations are being propagated inward. In contrast, the common BWB trend implies that the fluctuations likely more often happen first in the inner disk region.

  5. Doppler Tomography

    Science.gov (United States)

    Marsh, T. R.

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the accretion disc or stream. I discuss all of these and finish with some musings on possible future directions for the method. At the end I include a tabulation of Doppler maps published in refereed journals.

  6. Double-resonance optical-pumping effect and ladder-type electromagnetically induced transparency signal without Doppler background in cesium atomic vapour cell

    International Nuclear Information System (INIS)

    Yang Bao-Dong; Gao Jing; Liang Qiang-Bing; Wang Jie; Zhang Tian-Cai; Wang Jun-Min

    2011-01-01

    In a Doppler-broadened ladder-type cesium atomic system (6S 1/2 -6P 3/2 -8S 1/2 ), this paper characterizes electromagnetically induced transparency (EIT) in two different experimental arrangements, and investigates the influence of the double-resonance optical-pumping (DROP) effect on EIT in both arrangements. When the probe laser is weak, DROP is explicitly suppressed. When the probe laser is moderate, population of the intermediate level (6P 3/2 F' = 5) is remarkable, therefore DROP is mixed with EIT. An interesting bimodal spectrum with the broad component due to DROP and the narrow part due to EIT has been clearly observed in cesium 6S 1/2 F = 4−6P 3/2 F' = 5−8S 1/2 F″ = 4 transitions. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  7. The effect of isometric exercise of the hand on the synovial blood flow in patients with rheumatoid arthritis measured by color Doppler ultrasound

    DEFF Research Database (Denmark)

    Ellegaard, Karen; Torp-Pedersen, Søren; Lund, Hans

    2013-01-01

    made it possible to investigate the direct effect on blood supply in the synovium after training. In this case-control study, 24 patients with RA with USD activity in the wrist joint participated. The USD activity was measured by the color fraction (CF) (CF = colored pixels/total number of pixels...

  8. Process of optical excitation and relaxation of color center in synthetic diamond and its application to optoelectronics

    International Nuclear Information System (INIS)

    Nishida, Yoshio

    1989-01-01

    Irradiation of high-pressure synthesized diamond is carried out by using a nuclear reactor or a linac. Then, the effect of annealing on the color centers is observed. A study is made to identify different color centers and to provide techniques to control their introduction. Investigations cover the relation of color center formation with annealing temperature, dependence of color center formation on radiation dose, migration of H3 center and hydrogen, and applicability of five different color centers to optoelectronics. Next, a study is made of the formation and relaxation of the nitrogen vacancy (NV) center in a metastable excited state produced by optical excitation. An optical gain is essential to provide laser. Optical amplification is measured at the vibronic emission band of the NV center. An increase in absorption is detected, indicating that the NV center will not provide laser. In the optical excitation-relaxation process, the relaxation proceeds via a metastable state. Finally, hole burning of ZPL of the NV center is observed in the temperature range from 20K to 80K, and some of its features are described. (N.K.)

  9. Report from two cases of vesicular varices secondary to thrombosis of the aorta vein, diagnosed by ultrasound Doppler color and pressed

    International Nuclear Information System (INIS)

    Triana R, Gustavo; Romero E, Javier; Prada, Mario; Uribe, Tomas

    1999-01-01

    We report two cases of gallbladder varices diagnosed by ultrasound. The first one is a 71-year-old patient who was diagnosed with liver cirrhosis of unknown etiology. The second patient is a 27-year-old woman who was diagnosed with a hypercoagulability state. Both of them were evaluated with Doppler ultrasound of the esplenoportal circulation, gallbladder varices associated with complete portal vein thrombosis were found

  10. Characterization of Optical Attenuation by Colored Dissolved Organic Matter (CDOM) in the Red Sea

    KAUST Repository

    Tiwari, Surya Prakash

    2016-02-01

    Optical properties of colored dissolved organic matter (CDOM) control the downward irradiance in the ultraviolet and visible range of the electromagnetic radiation. CDOM is a strong absorber in shorter wavelengths (ultraviolet light) with steeper spectral slopes in the open ocean. Despite the importance of CDOM in understanding physical and biogeochemical processes in the marine environment, in situ measurements of optical properties in the Red Sea are sparse. This study comprises CDOM absorption from two different instruments (i.e. a spectrophotometer and WET Labs ac-s sensor), and assesses the variations in optical properties of CDOM in the Red Sea using data collected in 2014 and 2015. Three global inversion algorithms (Garver-Siegel-Maritorena model - GSM, Quasi-Analytical Algorithm - QAA, and the Constrained Linear-Matrix inversion model - CLM) were applied to recent data collected in the Red Sea, providing the comparison at five key selected wavelengths (412, 443, 490, 510, and 555 nm) demonstrated that in situ aCDOM values were higher than the values predicted from the three inversion algorithms and leads to underestimating in situ measurements. This finding is consistent with the conclusion of Brewin et al. (2015) that overestimation of chlorophyll in the Red Sea could be due to excessive CDOM.

  11. New experimental diffractive-optical data on E.Land's Retinex mechanism in human color vision: Part II

    Science.gov (United States)

    Lauinger, N.

    2007-09-01

    A better understanding of the color constancy mechanism in human color vision [7] can be reached through analyses of photometric data of all illuminants and patches (Mondrians or other visible objects) involved in visual experiments. In Part I [3] and in [4, 5 and 6] the integration in the human eye of the geometrical-optical imaging hardware and the diffractive-optical hardware has been described and illustrated (Fig.1). This combined hardware represents the main topic of the NAMIROS research project (nano- and micro- 3D gratings for optical sensors) [8] promoted and coordinated by Corrsys 3D Sensors AG. The hardware relevant to (photopic) human color vision can be described as a diffractive or interference-optical correlator transforming incident light into diffractive-optical RGB data and relating local RGB onto global RGB data in the near-field behind the 'inverted' human retina. The relative differences at local/global RGB interference-optical contrasts are available to photoreceptors (cones and rods) only after this optical pre-processing.

  12. Effects of acetazolamide on the micro- and macro-vascular cerebral hemodynamics: A diffuse optical and transcranial doppler ultrasound study

    OpenAIRE

    Zirak P.; Delgado-Mederos R.; Marti-Fabregas J.; Durduran T.

    2010-01-01

    Acetazolamide (ACZ) was used to stimulate the cerebral vasculature on ten healthy volunteers to assess the cerebral vasomotor reactivity (CVR). We have combined near infrared spectroscopy (NIRS), diffuse correlation spectroscopy (DCS) and transcranial Doppler (TCD) technologies to non-invasively assess CVR in real-time by measuring oxy- and deoxy-hemoglobin concentrations, using NIRS, local cerebral blood flow (CBF), using DCS, and blood flow velocity (CBFV) in the middle cerebral artery, usi...

  13. DISCOVERING BRIGHT QUASARS AT INTERMEDIATE REDSHIFTS BASED ON OPTICAL/NEAR-INFRARED COLORS

    International Nuclear Information System (INIS)

    Wu, Xue-Bing; Zuo, Wenwen; Yang, Jinyi; Yang, Qian; Wang, Feige

    2013-01-01

    The identification of quasars at intermediate redshifts (2.2 < z < 3.5) has been inefficient in most previous quasar surveys since the optical colors of quasars are similar to those of stars. The near-IR K-band excess technique has been suggested to overcome this difficulty. Our recent study also proposed to use optical/near-IR colors for selecting z < 4 quasars. To verify the effectiveness of this method, we selected a list of 105 unidentified bright targets with i ≤ 18.5 from the quasar candidates of SDSS DR6 with both SDSS ugriz optical and UKIDSS YJHK near-IR photometric data, which satisfy our proposed Y – K/g – z criterion and have photometric redshifts between 2.2 and 3.5 estimated from the nine-band SDSS-UKIDSS data. We observed 43 targets with the BFOSC instrument on the 2.16 m optical telescope at Xinglong station of the National Astronomical Observatory of China in the spring of 2012. We spectroscopically identified 36 targets as quasars with redshifts between 2.1 and 3.4. The high success rate of discovering these quasars in the SDSS spectroscopic surveyed area further demonstrates the robustness of both the Y – K/g – z selection criterion and the photometric redshift estimation technique. We also used the above criterion to investigate the possible stellar contamination rate among the quasar candidates of SDSS DR6, and found that the rate is much higher when selecting 3 < z < 3.5 quasar candidates than when selecting lower redshift candidates (z < 2.2). The significant improvement in the photometric redshift estimation when using the nine-band SDSS-UKIDSS data over the five-band SDSS data is demonstrated and a catalog of 7727 unidentified quasar candidates in SDSS DR6 selected with optical/near-IR colors and having photometric redshifts between 2.2 and 3.5 is provided. We also tested the Y – K/g – z selection criterion with the recently released SDSS-III/DR9 quasar catalog and found that 96.2% of 17,999 DR9 quasars with UKIDSS Y- and K

  14. Generalized Ocean Color Inversion Model for Retrieving Marine Inherent Optical Properties

    Science.gov (United States)

    Werdell, P. Jeremy; Franz, Bryan A.; Bailey, Sean W.; Feldman, Gene C.; Boss, Emmanuel; Brando, Vittorio E.; Dowell, Mark; Hirata, Takafumi; Lavender, Samantha J.; Lee, ZhongPing; hide

    2013-01-01

    Ocean color measured from satellites provides daily, global estimates of marine inherent optical properties (IOPs). Semi-analytical algorithms (SAAs) provide one mechanism for inverting the color of the water observed by the satellite into IOPs. While numerous SAAs exist, most are similarly constructed and few are appropriately parameterized for all water masses for all seasons. To initiate community-wide discussion of these limitations, NASA organized two workshops that deconstructed SAAs to identify similarities and uniqueness and to progress toward consensus on a unified SAA. This effort resulted in the development of the generalized IOP (GIOP) model software that allows for the construction of different SAAs at runtime by selection from an assortment of model parameterizations. As such, GIOP permits isolation and evaluation of specific modeling assumptions, construction of SAAs, development of regionally tuned SAAs, and execution of ensemble inversion modeling. Working groups associated with the workshops proposed a preliminary default configuration for GIOP (GIOP-DC), with alternative model parameterizations and features defined for subsequent evaluation. In this paper, we: (1) describe the theoretical basis of GIOP; (2) present GIOP-DC and verify its comparable performance to other popular SAAs using both in situ and synthetic data sets; and, (3) quantify the sensitivities of their output to their parameterization. We use the latter to develop a hierarchical sensitivity of SAAs to various model parameterizations, to identify components of SAAs that merit focus in future research, and to provide material for discussion on algorithm uncertainties and future ensemble applications.

  15. [Pilot study of echocardiographic studies using color- and pulsed-wave spectral Doppler methods in blue-crowned amazons (Amazona ventralis) and blue-fronted amazons (Amazona a. aestiva)].

    Science.gov (United States)

    Pees, M; Straub, J; Schumacher, J; Gompf, R; Krautwald-Junghanns, M E

    2005-02-01

    Colour-flow and pulsed-wave spectral Doppler echocardiography was performed on 6 healthy, adult Hispaniolan amazon parrots (Amazona ventralis) and 6 blue-fronted amazon parrots (Amazona a. aestiva) to establish normal reference values. Birds were anesthetized with isoflurane in oxygen and placed in dorsal recumbency. An electrocardiogram was recorded continuously and birds were imaged with a micro-phased-array scanner with a frequency of 7.0 MHz. After assessment of cardiac function in 2-D-echocardiography, blood flow across the left and the right atrioventricular valve and across the aortic valve was determined using color-flow and pulsed-wave spectral Doppler echocardiography. Diastolic inflow (mean value +/- standard deviation) into the left ventricle was 0.17 +/- 0.02 m/s (Hispaniolan amazons) and 0.18 +/- 0.03 m/s (Blue fronted amazons). Diastolic inflow into the right ventricle was 0.22 +/- 0.05 m/s (Hispaniolan amazons) and 0.22 +/- 0.04 m/s (Blue fronted amazons). Velocity across the aortic valve was 0.84 +/- 0.07 m/s (Hispaniolan amazons) and 0.83 +/- 0.08 m/s (Blue fronted amazons). Systolic pulmonary flow could not be detected in any of the birds in this study. No significant differences were evident between the two species examined. Results of this study indicate that Doppler echocardiography is a promising technique to determine blood flow in the avian heart. Further studies in other avian species are needed to establish reference values for assessment of cardiac function in diseased birds.

  16. Diagnosic evaluation study of color doppler ultrasonic examination in abdominal wall endometriosis%彩色多普勒高频超声对腹壁子宫内膜异位症的诊断价值研究

    Institute of Scientific and Technical Information of China (English)

    史淼; 亓恒涛; 王倩; 张东东; 章阳

    2014-01-01

    Objective To explore the color doppler ultrasound manifestation of abdominal wall endometriosis,and evaluate its clinical value. Methods The manifestation of two-dimensional high frequency ultrasonography and color doppler imaging of 36 patients withabdominal wall endometriosis,which proven by surgery and pathology,were retrospectively analyzed.Results Among the 36 patients with abdominal wall endometriosis,1 6 cases located in fat layer,20 cases in muscular layer,with diameter ranging from 1 .1 to 5 .2 cm.With two-dimensionalultrasonography,there was no capsule,but with irregular morphology,blurred margins,low echoes inside and some parts of irregular no-echo areas.The size and internal echo of the mass changed respectively according to the menstruation.Color doppler ultrasound showed scattered or striped flow signals in the lesion,whose artery displayed low-speed and high resistance frequency spectrum.The accuracy and misdiagnosis rate of ultrasonography were 83.3% and 1 6.7%, respectively.Conclusions The color doppler ultrasound may directlydisplay the size,morphology,condition of internal echo and blood inflow of the abdominal wall endometriosis lesion.Therefore,it is the first choice of imaging examination for the diagnosis of abdominal wall endometriosis.%目的:探讨腹壁子宫内膜异位症的彩色多普勒高频超声表现,评价其临床应用价值。方法回顾性分析2010年2月至2013年12月,山东省聊城市人民医院经手术病理证实的腹壁子宫内膜异位症患者36例的高频超声二维图像及彩色多普勒超声表现。结果36例腹壁子宫内膜异位症患者中,位于脂肪层内16例,位于肌层内20例,直径1.1~5.2 cm。二维超声表现:无包膜,形态不规则,边缘不光滑,内部为不均质低回声,随月经的不同时期肿块大小及回声呈相应改变。彩色多普勒超声显示病灶内部可见点状或条状血流信号,其动脉均为低速高阻频谱。

  17. Transvaginal color Doppler ultrasound in the diagnosis of endometrial lesions%经阴道彩色多普勒超声在子宫内膜病变诊断的应用价值

    Institute of Scientific and Technical Information of China (English)

    高鸣

    2015-01-01

    目的 探讨经阴道彩色多普勒超声在子宫内膜病变诊断中的应用价值,总结其应用经验.方法 对90例不规则阴道流血患者行经阴道彩色多普勒超声检查,分析其超声影像学资料,并将超声检查结果与诊刮以及患者术后病理诊断结果相对照.结果 本研究90例患者经阴道彩色多普勒超声检查确诊86例,其中子宫内膜增生36例、子宫内膜息肉42例,子宫内膜癌8例,确诊率为95.64%;漏诊4例,漏诊率为4.36%,其中1例子宫内膜癌病变,3例子宫内膜增生病变.结论 经阴道彩色多普勒超声检查子宫内膜病变操作简便、准确性高,超声检查时应注意测量子宫内膜厚度,观察内膜形态、内膜与肌层的关系、内膜回声特点以及子宫内膜内血流情况及阻力指数,作为诊断子宫内膜病变的重要检查方法,还需要结合患者的临床表现及其他影像学检查手段,以提高其确诊率.%Objective To investigate the application value of transvaginal color Doppler ultrasound in the diagnosis of endometrial lesions,and summarize the application experience.Methods Ninety patients with irregular vaginal bleeding underwent transvaginal color Doppler ultrasound examination,the ultrasound image data were analyzed,and the ultrasonic inspection results and curettage and postoperative pathological diagnosis results were compared.Results Among the 90 cases,86 cases were diagnosed by transvaginal color Doppler ultrasound,of which 36 cases of endometrial hyperplasia,42 cases of endometrial polyps,endometrial carcinoma in 8 cases,the diagnosis rate was 95.64% ; 4 cases of missed diagnosis,the missed diagnosis rate was 4.36%,in which l case of endometrial carcinoma lesions,3 cases of uterus hyperplasia lesions.Conclusions Transvaginal color Doppler ultrasonography for endometrial lesions has simple operation,high accuracy,we should pay attention to measure the thickness of endometrium,endometrial morphology

  18. Application of Color Doppler Ultrasound in Renal Medullary Calcium%彩色多普勒超声在肾髓质钙质沉着症中的应用分析

    Institute of Scientific and Technical Information of China (English)

    金丽梅

    2016-01-01

    目的:分析彩色多普勒超声在肾髓质钙沉着症中的应用价值。方法回顾性分析2011—2015年期间在该院行彩色多普勒超声诊断肾髓质钙沉着症的68例患者的临床资料,观察患者的超声诊断特点以及血流动力学改变。结果68例行彩色多普勒超声诊断肾髓质钙沉着症的患者中,诊断阳性共65例,阴性3例,诊断的准确率为95.6%,65例肾髓质钙沉着症患者中包括皮质型30例,髓质型32例,混合型3例,患者的两侧肾脏大小正常,形态对称,包膜光滑,皮质和髓质界限较为清楚,肾脏的皮质厚度和回声均正常,在患者的髓质内,有密集点状的强回声,形态和椎体的形态基本一致,有一侧有弱声影。结论彩色多普勒超声在肾髓质钙沉着症中应用,准确率较高,可以有效的显示内部的形态、血流变化等指标,具有重要的临床诊断价值。%Objective To analyze the value of color Doppler ultrasound in the renal medulla of calcium applications. Methods Convenient selection a retrospective analysis of clinical data by color Doppler ultrasound diagnosis of renal medullary calcinosis disease 68 patients were retrospectively analyzed the period from 2011 to 2015, observed in patients with ultrasonic diagnostic characteristics and hemodynamic change. Results 68 patients with routine color Doppler ultra-sound diagnosis of renal medullary calcinosis disease, the diagnosis of a total of65 positive cases, negative in 3 cases, the diagnostic accuracy was 95.6%, 65 cases of renal medullary calcinosis patients included cortical 30 cases, 32 cases of medullary, mixed three cases, both sides of the patient's normal kidney size, shape symmetry, smooth coated, cortex and medulla boundaries more clearly, renal cortical thickness and echo were normal in patients within the medulla, a strong e-cho dense point-like, form and shape of the vertebral body are basically the same, there is one

  19. Color Doppler evaluation of left gastric vein hemodynamics in cirrhosis with portal hypertension and its correlation with esophageal varices and variceal bleed

    International Nuclear Information System (INIS)

    Adithan, Subathra; Venkatesan, Bhuvaneswari; Sundarajan, Elangovan; Kate, Vikram; Kalayarasan, Raja

    2010-01-01

    The purpose of this study was to assess the value of Doppler evaluation of left gastric vein hemodynamics when monitoring portal hypertension patients, by correlating Doppler ultrasonography (USG) parameters with the severity of esophageal varices and occurrence of variceal bleeding. This study was carried out on 100 patients using Doppler USG and endoscopy. Forty-seven of these were patients with cirrhosis with portal hypertension, who had not had a recent variceal bleed (group 1) and 26 were patients with cirrhosis with portal hypertension, with a recent history of bleeding (group 2). The control group comprised of 27 subjects who did not have liver disease or varices on endoscopy (group 3). The hemodynamic parameters, namely the diameter of the left gastric vein and the direction and flow velocity in the vessel, were compared in these groups, with the grade of esophageal varices. Hepatofugal flow velocity in the left gastric vein was higher in patients with large-sized varices compared to those patients with small-sized varices (P < 0.001). The left gastric vein hepatofugal flow velocity was higher in patients with a recent variceal bleed than in those patients without a history of a recent variceal bleed (P < 0.0149). Large-sized varices were more commonly found in patients with a history of a recent variceal bleed (P < 0.0124). Left gastric vein hemodynamics were found to correlate with the severity of the varices and the occurrence of recent variceal bleed in patients with cirrhosis with portal hypertension. Evaluation of the left gastric vein portal dynamics could be helpful in monitoring the progress of the disease in these patients

  20. Optical Interference Coatings Design Contest 2013: angle-independent color mirror and shortwave infrared/midwave infrared dichroic beam splitter.

    Science.gov (United States)

    Hendrix, Karen; Kruschwitz, Jennifer D T; Keck, Jason

    2014-02-01

    An angle-independent color mirror and an infrared dichroic beam splitter were the subjects of a design contest held in conjunction with the 2013 Optical Interference Coatings topical meeting of the Optical Society of America. A total of 17 designers submitted 63 designs, 22 for Problem A and 41 for Problem B. The submissions were created through a wide spectrum of design approaches and optimization strategies. Michael Trubetskov and Weidong Shen won the first contest by submitting color mirror designs with a zero color difference (ΔE00) between normal incidence and all other incidence angles up to 60° as well as the thinnest design. Michael Trubetskov also won the second contest by submitting beam-splitter designs that met the required transmission while having the lowest mechanical coating stress and thinnest design. Fabien Lemarchand received the second-place finish for the beam-splitter design. The submitted designs are described and evaluated.

  1. Ocean Optics Protocols for Satellite Ocean Color Sensor Validation. Volume 2; Revised

    Science.gov (United States)

    Mueller, James L. (Editor); Fargion, Giulietta S. (Editor); Trees, C.; Austin, R. W.; Pietras, C. (Editor); Hooker, S.; Holben, B.; McClain, Charles R.; Clark, D. K.; Yuen, M.

    2002-01-01

    This document stipulates protocols for measuring bio-optical and radiometric data for the SIMBIOS Project. It supersedes the earlier version, and is organized into four parts: Introductory Background, Instrument Characteristics, Field Measurements and Data Analysis, Data Reporting and Archival. Changes in this revision include the addition of three new chapters: (1) Fundamental Definitions, Relationships and Conventions; (2) MOBY, A Radiometric Buoy for Performance Monitoring and Vicarious Calibration of Satellite Ocean Color Sensors: Measurement and Data Analysis Protocols; and (3) Normalized Water-Leaving Radiance and Remote Sensing Reflectance: Bidirectional Reflectance and Other Factors. Although the present document represents another significant, incremental improvement in the ocean optics protocols, there are several protocols that have either been overtaken by recent technological progress, or have been otherwise identified as inadequate. Revision 4 is scheduled for completion sometime in 2003. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational Project. The contributions are published as submitted, after only minor editing to correct obvious grammatical or clerical errors.

  2. Ocean Optics Protocols for Satellite Ocean Color Sensor Validation. Volume 1; Revised

    Science.gov (United States)

    Mueller, James L. (Editor); Fargion, Giulietta (Editor); Mueller, J. L.; Trees, C.; Austin, R. W.; Pietras, C.; Hooker, S.; Holben, B.; McClain, Charles R.; Clark, D. K.; hide

    2002-01-01

    This document stipulates protocols for measuring bio-optical and radiometric data for the SIMBIOS Project. It supersedes the earlier version, and is organized into four parts: Introductory Background, Instrument Characteristics, Field Measurements and Data Analysis, Data Reporting and Archival. Changes in this revision include the addition of three new chapters: (1) Fundamental Definitions, Relationships and Conventions; (2) MOBY, A Radiometric Buoy for Performance Monitoring and Vicarious Calibration of Satellite Ocean Color Sensors: Measurement and Data Analysis Protocols; and (3) Normalized Water-Leaving Radiance and Remote Sensing Reflectance: Bidirectional Reflectance and Other Factors. Although the present document represents another significant, incremental improvement in the ocean optics protocols, there are several protocols that have either been overtaken by recent technological progress, or have been otherwise identified as inadequate. Revision 4 is scheduled for completion sometime in 2003. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational Project. The contributions are published as submitted, after only minor editing to correct obvious grammatical or clerical errors.

  3. Non-invasive assessment of fibrosis using color Doppler ultrasound in patients with hepatitis C virus in the Amazon rainforest, Brazil.

    Science.gov (United States)

    Leão, Jorge; Brock, Marianna; Castilho, Márcia; Scariot, André; Scariot, Ana; Braga, Wornei

    2012-02-01

    The purpose of this study was to correlate morphologic and hemodynamic Doppler ultrasound findings as indicators of the degree of inflammation and fibrosis and to diagnose chronic vital hepatitis complications and progression. A prospective, descriptive study of a case series was conducted that analyzed Doppler ultrasound images of the liver and portal system and used the portal vein congestion index, hepatic and splenic artery impedance indices, and the liver vascular index. Of 50 patients positive for antibodies against hepatitis C virus, morphologic changes highlighted increased hepatic parenchyma echogenicity in 24%, and increased gall blander echogenicity and wall thickness in 4%. The most common hemodynamic changes observed were reduced flow velocity in the portal vein trunk in 26%, congestion index changes in 12%, liver vascular index changes in 16%, and splenic and hepatic artery impedance index changes in 14%. These indices were shown to be associated with alanine aminotransferase levels, which suggested that they are important liver damage indicators in the early phase of infection with hepatitis C virus.

  4. Compact 6 dB Two-Color Continuous Variable Entangled Source Based on a Single Ring Optical Resonator

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2018-02-01

    Full Text Available Continuous-variable entangled optical beams at the degenerate wavelength of 0.8 μm or 1.5 μm have been investigated extensively, but separately. The two-color entangled states of these two useful wavelengths, with sufficiently high degrees of entanglement, still lag behind. In this work, we analyze the various limiting factors that affect the entanglement degree. On the basis of this, we successfully achieve 6 dB of two-color quadrature entangled light beams by improving the escape efficiency of the nondegenerate optical amplifier, the stability of the phase-locking servo system, and the detection efficiency. Our entangled source is constructed only from a single ring optical resonator, and thus is highly compact, which is suitable for applications in long-distance quantum communication networks.

  5. Christian Andreas Doppler--the man and his legacy.

    Science.gov (United States)

    Coman, I M

    2005-01-01

    Reminding the life and legacy of the Austrian Scientist who discovered the famous 'Doppler Effect'. C.A. Doppler was born the 29th of November 1803 in Salzburg. After studies in Linz and Vienna, he graduated in mathematics, became assistant at the University and later worked as a professor in Prague. Back to Vienna, he was appointed as professor at the Polytechnic School and --in 1850--as first director of the new Institute of Physics. C.A. Doppler did publish on magnetism, electricity, optics, and astronomy. He remains in the history of science due to the discovery presented (May 25, 1842) at the Royal Bohemian Society of Science entitled "On the colored light of the double stars and certain other stars of the heavens"; the paper described (applied to light) the shift of frequency which bears nowadays his name. The theory was later experimentally proven and--extended for any electromagnetic and acoustic waves--got myriads if applications in astronomy, physics, aviation, meteorology, and health science. Satomura in Japan (1955) published it's first ultrasound vascular application--with successive achievements in the next decades. Doppler ultrasonagraphy became the main noninvasive instrument for functional assesment of heart and vessels.

  6. [Optical characteristics of colored dissolved organic material (CDOM) in Yangtze Estuary].

    Science.gov (United States)

    Zhu, Wei-Jian; Shen, Fang; Hong, Guan-Lin

    2010-10-01

    Absorption property of colored dissolved organic material (CDOM) is one of the most important contents to remote sensing of ocean color in estuarine and coastal areas. In this study, the optical properties and mixing behavior of CDOM in surface water of Yangtze Estuary were discussed according to the two surveys in August of 2008 and May of 2009. Based on the research, the absorption coefficient and spectral slope were discussed. It was found that in summer of 2008 CDOM absorption coefficients at 440 nm [a(g) (440)], ranged from 0.20 m(-1) to 0.73 m(-1), while the coefficients in 2009 varied between 0.20 m(-1) and 0.77 m(-1). Statistics showed that the power function model fitted the best in the regression analysis of CDOM absorption spectral. The spectral slopes (S(g2)) of CDOM calculated by the power function model ranged from 5.10 to 7.90 in Summer of 2008 and from 2.95 to 6.11 in Spring of 2009. The highest absorption coefficients of two cruises appeared both in the south passage of the Yangtze Estuary. The absorption coefficient in surfer water was observed varied tremendously in the estuary and the offshore area. And the main reason is affected by the turbidity maximum zone. It is observed that the absorption coefficients of CDOM tended to a homogeneous distribution whilst the layers of water mixed tempestuously, but otherwise it always showed a conservative mixing behavior. Because of the frequent mixture, there is not assured correlativity between S(g2) and a(g) (440). In the offshore area of Yangtze Estuary, the effecting of local production cannot be negligent, which differed from the estuary area. Yet when the hydrological environment was relatively stable, the negative relationship between them was very clear. In conclusion, the optical properties and mixing behavior of CDOM had showed tremendous different characteristics from inside the estuary to outside the estuary because of the influence of complex physical, chemical and hydrology conditions.

  7. Our Continuing Program of Optical Color Measurements of Centaurs and KBOs

    Science.gov (United States)

    Romanishin, W.; Tegler, S. C.; Consolmagno, G. J.

    2012-05-01

    We report on our continuing program of BVR color measurement of Centaurs and KBOs. Most of our measurements have been made with the Vatican Advanced Technology Telescope (VATT). We report of new colors obtained through October 2011.

  8. SRTM Radar Image, Wrapped Color as Height/EarthKam Optical Honolulu, Hawaii

    Science.gov (United States)

    2000-01-01

    These two images of the eastern part of the island of Oahu, Hawaii provide information on regional topography and show the relationship between urban development and sensitive ecosystems. On the left is a topographic radar image collected by the Shuttle Radar Topography Mission (SRTM.) On the right is an optical image acquired by a digital camera on the Space Shuttle Endeavour, which carried SRTM. Features of interest in this scene include Diamond Head (an extinct volcano at the lower center), Waikiki Beach (just left of Diamond Head), the Punchbowl National Cemetery (another extinct volcano, at the foot of the Koolau Mountains), downtown Honolulu and Honolulu airport (lower left of center), and Pearl Harbor (at the left edge.)The topography shows the steep, high central part of the island surrounded by flatter coastal areas. The optical image shows the urban areas and a darker, forested region on the mountain slopes. The clouds in the optical image and the black areas on the topographic image are both a result of the steep topography. In this tropical region, high mountain peaks are usually covered in clouds. These steep peaks also cause shadows in the radar data, resulting in missing data 'holes.' A second pass over the island was obtained by SRTM and will be used to fill in the holes.The left image combines two types of SRTM data. Brightness corresponds to the strength of the radar signal reflected from the ground, while colors show the elevation. Each color cycle (from pink through blue and back to pink) represents 400 meters (1,300 feet) of elevation difference, like the contour lines on a topographic map. This image contains about 2,400 meters (8,000 feet) of total relief. The optical image was acquired by the Shuttle Electronic Still Camera with a lens focal length of 64 millimeters (2.5 inches) for the Earth Knowledge Acquired by Middle school students (EarthKAM) project. EarthKAM has flown on five space shuttle missions since 1996. Additional information

  9. High-resolution color Doppler ultrasonographic characteritics of lymphatic malformations%淋巴管畸形的高频超声与彩色多普勒特点

    Institute of Scientific and Technical Information of China (English)

    张梅; 谷凌云; 李宪坤; 许雅琴; 郝岩

    2012-01-01

    目的 研究淋巴管畸形的高频超声及彩色多普勒超声表现特点并进行分析、总结.方法 应用高频超声及彩色多普勒超声对23例淋巴管畸形的二维灰阶超声声像图及彩色血流信号进行回顾性研究.超声扫查内容包括:病变大小、边界、内部回声、彩色血流信号及用脉冲多普勒测量血流速度.结果 17例淋巴管畸形(74%,17/23)位于颈部、颌下或腋下,6例位于其他部位;21例位于皮下组织内,其中3例同时累及真皮及肌层.13例大囊型淋巴管畸型,均显示为较大的无回声区,有分隔,壁光滑,其中2例大囊型合并感染,无回声区内有稀疏低回声;5例混合型淋巴管畸形,为淋巴管畸形和血管畸形混合存在,超声显示为大小不等的无回声区有分隔,合并局部微小无回声区或不规则的小的实性低回声区,其中3例侵及肌层;5例微囊型淋巴管畸形,超声显示以无回声区为主,内有少量的低回声区,形成囊实混合性病变.所有病例无回声区内彩色多普勒扫查均无彩色血流信号.8例大囊型及3例混合型淋巴管畸形周边扫查到彩色血流信号,2例微囊型内部实性低回声内显示有彩色血流信号.脉冲多普勒检查最大血流速度18~73 cm/s,阻力指数0.55~0.72.结论 淋巴管畸形的高频超声及彩色超声多普勒成像有显著的特点,以较大的无回声区为主,多发可有分隔,无回声区内无血流信号,大部分位于皮下组织内,基于以上特点,可确诊大部分病例,因而高频超声及彩色多普勒是诊断淋巴管畸形的较好方法.%Objective To analyse the characteristics and diagnostic value of high resolution grayscale and color Doppler ultrasound in lymphatic malformations . Methods Twenty-three lymphatic malformations were evaluated by 7-12 MHz high-resolution grayscale and color Doppler ultrasound . All the cases were comfirmed by histopathologic diagnosis . The size, location, margin, echo

  10. A fully integrated optical detector with a-Si:H based color photodiodes

    Energy Technology Data Exchange (ETDEWEB)

    Watty, Krystian; Merfort, Christian; Seibel, Konstantin; Schoeler, Lars; Boehm, Markus [Institute for Microsystem Technologies (IMT), University of Siegen, Hoelderlinstr. 3, 57076 Siegen (Germany)

    2010-03-15

    The fabrication of an electrophoresis separation microchip with monolithic integrated excitation light source and variospectral photodiodes for absorption detection is presented in this paper. Microchip based separation techniques are essential elements in the development of fully integrated micro-total analysis systems ({mu}-TAS). An integrated microfluidic device, like an application specific lab-on-microchip (ALM) (Seibel et al., in: MRS Spring Meeting, San Francisco, USA, 2005 1), includes all components, necessary to perform a chemical analysis on chip and it can be used as a stand-alone unit directly at the point of sampling. Variospectral diodes based on hydrogenated amorphous silicon (a-Si:H) technology allow for advanced optical detection schemes, because the spectral sensitivity of the devices can be tailored to fit the emission of specific fluorescent markers. Important features of a-Si:H variospectral photodiodes are a high dynamic range, a bias-tunable spectral sensitivity and a very good linearity for the separation of mixed color signals. Principle of ALM device. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  11. Novel 2D-sequential color code system employing Image Sensor Communications for Optical Wireless Communications

    Directory of Open Access Journals (Sweden)

    Trang Nguyen

    2016-06-01

    Full Text Available The IEEE 802.15.7r1 Optical Wireless Communications Task Group (TG7r1, also known as the revision of the IEEE 802.15.7 Visible Light Communication standard targeting the commercial usage of visible light communication systems, is of interest in this paper. The paper is mainly concerned with Image Sensor Communications (ISC of TG7r1; however, the major challenge facing ISC, as addressed in the Technical Consideration Document (TCD of TG7r1, is Image Sensor Compatibility among the variety of different commercial cameras on the market. One of the most challenging but interesting compatibility requirements is the need to support the verified presence of frame rate variation. This paper proposes a novel design for 2D-sequential color code. Compared to a QR-code-based sequential transmission, the proposed design of 2D-sequential code can overcome the above challenge that it is compatible with different frame rate variations and different shutter operations, and has the ability to mitigate the rolling effect as well as the rotating effect while effectively minimizing transmission overhead. Practical implementations are demonstrated and a performance comparison is presented.

  12. Evaluation of pelvic varicose veins using color Doppler ultrasound: comparison of results obtained with ultrasound of the lower limbs, transvaginal ultrasound, and phlebography Avaliação de varizes pélvicas por Doppler colorido: comparação dos resultados obtidos com ultrassom dos membros inferiores, ultrassom transvaginal e flebografia

    Directory of Open Access Journals (Sweden)

    Fanilda Souto Barros

    2010-06-01

    Full Text Available Introduction: Pelvic varicose veins, one of the main causes of chronic pelvic pain and dyspareunia, are an important source of reflux for lower limb varicose veins, especially in recurrent cases. Color Doppler ultrasound of the lower limbs and transvaginal ultrasound are the noninvasive diagnostic methods most commonly used to assess pelvic venous insufficiency, whereas phlebography is still considered as the gold standard. Objectives: To determine the prevalence of lower limb varicose veins originating from the pelvis in a group of female patients and to determine the agreement between results obtained via color Doppler ultrasound of the lower limbs, transvaginal ultrasound, and phlebography. Methods: The sample comprised female patients referred to a vascular laboratory for lower limb screening. Patients diagnosed with deep venous thrombosis were excluded. Data analysis included kappa coefficient of agreement, McNemar's test, sensitivity and specificity values. Results: Of a total of 1,020 patients, 124 (12.2% had findings compatible with reflux of pelvic origin. Among these patients, 51 (41.2% were recurrent cases. A total of 249 were submitted to transvaginal ultrasound. There was significant agreement between lower limb ultrasonographic findings and transvaginal findings. Phlebography was performed in 54 patients. The comparison between transvaginal ultrasound and phlebography was associated with a 96.2% sensitivity and 100% specificity. Conclusions: The authors draw attention to the relatively high prevalence of lower limb varicose veins originating from the pelvis, suggesting an important but underdiagnosed cause of recurrent varicose veins.Introdução: AS VARIZES Pélvicas, uma das principais causas de dor pélvica crônica e dispareunia, são uma importante fonte de refluxo para as varizes dos membros inferiores, especialmente em casos recorrentes. O Doppler colorido dos membros inferiores e o ultrassom transvaginal são os m

  13. Efficacy of a Deep Learning System for Detecting Glaucomatous Optic Neuropathy Based on Color Fundus Photographs.

    Science.gov (United States)

    Li, Zhixi; He, Yifan; Keel, Stuart; Meng, Wei; Chang, Robert T; He, Mingguang

    2018-03-02

    To assess the performance of a deep learning algorithm for detecting referable glaucomatous optic neuropathy (GON) based on color fundus photographs. A deep learning system for the classification of GON was developed for automated classification of GON on color fundus photographs. We retrospectively included 48 116 fundus photographs for the development and validation of a deep learning algorithm. This study recruited 21 trained ophthalmologists to classify the photographs. Referable GON was defined as vertical cup-to-disc ratio of 0.7 or more and other typical changes of GON. The reference standard was made until 3 graders achieved agreement. A separate validation dataset of 8000 fully gradable fundus photographs was used to assess the performance of this algorithm. The area under receiver operator characteristic curve (AUC) with sensitivity and specificity was applied to evaluate the efficacy of the deep learning algorithm detecting referable GON. In the validation dataset, this deep learning system achieved an AUC of 0.986 with sensitivity of 95.6% and specificity of 92.0%. The most common reasons for false-negative grading (n = 87) were GON with coexisting eye conditions (n = 44 [50.6%]), including pathologic or high myopia (n = 37 [42.6%]), diabetic retinopathy (n = 4 [4.6%]), and age-related macular degeneration (n = 3 [3.4%]). The leading reason for false-positive results (n = 480) was having other eye conditions (n = 458 [95.4%]), mainly including physiologic cupping (n = 267 [55.6%]). Misclassification as false-positive results amidst a normal-appearing fundus occurred in only 22 eyes (4.6%). A deep learning system can detect referable GON with high sensitivity and specificity. Coexistence of high or pathologic myopia is the most common cause resulting in false-negative results. Physiologic cupping and pathologic myopia were the most common reasons for false-positive results. Copyright © 2018 American Academy of Ophthalmology. Published by

  14. 正常中晚期妊娠输尿管射尿的彩色多普勒检查%Observations of ureteral jets in normal second- and third-trimester pregnancy with color Doppler sonography

    Institute of Scientific and Technical Information of China (English)

    王家刚

    2001-01-01

    目的:了解正常中晚期妊娠输尿管的尿动力学改变是否影响输尿管射尿。方法:彩色多普勒超声观察32例中晚期妊娠妇女和11例非妊娠对照者膀胱射尿情况,观察时间5分钟。结果:妊娠受试者平均射尿5.9次/分,左、右侧射尿频率平均差异百分比为49%。对照组平均射尿7.3次/分,左、右射尿频率差异百分比为13%。受试组与对照组之间射尿对称性方面具有显著性差异(P<0.05)。32例妊娠受试者中有7例有单侧射尿缺乏,而对照者中无1例单侧射尿缺乏。结论:在妊娠中晚期,由于两侧输尿管射尿的不对称性,用彩色多普勒超声检测输尿管射尿诊断中晚期妊娠合并输尿管结石应慎用。%Objective: To understand whether ureteral urodynamic changes accompanying normal second- and third-trimester pregnancy altered the pattern of ureteral jets. Methods: Ureteral jets were observed with color Doppler sonography for five minutes in 32women during the second or third trimester of pregnancy and in 11 non-pregnant controls. Result: A mean of 5.9 jets/ minute were detected in the pregnant subjects. The mean percentage difference in frequency of jets between the right and left sides was 49%. A mean of 7.3 jets/ minute were detected and the mean percentage difference was 13% for controls. The two groups were significantly different in jet symmetry (P<0.05). Unilateral absence of jets was observed in seven pregnant subjects and in no controls. Conclusion: Because of asymmetry in ureteral jet between the left and right sides during the later stages of pregnacy, caution is recommended in the use of color Doppler sonography to diagnose ureteral urolithiasis during the later stages of pregnancy.

  15. QUENCHING DEPENDS ON MORPHOLOGIES: IMPLICATIONS FROM THE ULTRAVIOLET-OPTICAL RADIAL COLOR DISTRIBUTIONS IN GREEN VALLEY GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Zhizheng; Lin, Weipeng [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Science, 80 Nandan Road, Shanghai 200030 (China); Li, Jinrong; Kong, Xu [Center of Astrophysics, University of Science and Technology of China, Jinzhai Road 96, Hefei 230026 (China); Wang, Jing, E-mail: panzz@shao.ac.cn, E-mail: linwp@shao.ac.cn [CSIRO Astronomy and Space Science, Australia Telescope National Facility, PO Box 76, Epping, NSW 1710 (Australia)

    2014-09-01

    In this Letter, we analyze the radial ultraviolet-optical color distributions in a sample of low redshift green valley galaxies, with the Galaxy Evolution Explorer (GALEX)+Sloan Digital Sky Survey (SDSS) images, to investigate how the residual recent star formation is distributed in these galaxies. We find that the dust-corrected u – r colors of early-type galaxies (ETGs) are flat out to R {sub 90}, while the colors monotonously turn blue when r > 0.5 R {sub 50} for late-type galaxies (LTGs). More than half of the ETGs are blue-cored and have remarkable positive NUV – r color gradients, suggesting that their star formations are centrally concentrated. The rest have flat color distributions out to R {sub 90}. The centrally concentrated star formation activity in a large portion of ETGs is confirmed by the SDSS spectroscopy, showing that ∼50% of the ETGs have EW(Hα) >6.0 Å. Of the LTGs, 95% show uniform radial color profiles, which can be interpreted as a red bulge plus an extended blue disk. The links between the two kinds of ETGs, e.g., those objects having remarkable ''blue-cores'' and those having flat color gradients, are less known and require future investigations. It is suggested that the LTGs follow a general model by which quenching first occurs in the core regions, and then finally extend to the rest of the galaxy. Our results can be re-examined and have important implications for the IFU surveys, such as MaNGA and SAMI.

  16. QUENCHING DEPENDS ON MORPHOLOGIES: IMPLICATIONS FROM THE ULTRAVIOLET-OPTICAL RADIAL COLOR DISTRIBUTIONS IN GREEN VALLEY GALAXIES

    International Nuclear Information System (INIS)

    Pan, Zhizheng; Lin, Weipeng; Li, Jinrong; Kong, Xu; Wang, Jing

    2014-01-01

    In this Letter, we analyze the radial ultraviolet-optical color distributions in a sample of low redshift green valley galaxies, with the Galaxy Evolution Explorer (GALEX)+Sloan Digital Sky Survey (SDSS) images, to investigate how the residual recent star formation is distributed in these galaxies. We find that the dust-corrected u – r colors of early-type galaxies (ETGs) are flat out to R 90 , while the colors monotonously turn blue when r > 0.5 R 50 for late-type galaxies (LTGs). More than half of the ETGs are blue-cored and have remarkable positive NUV – r color gradients, suggesting that their star formations are centrally concentrated. The rest have flat color distributions out to R 90 . The centrally concentrated star formation activity in a large portion of ETGs is confirmed by the SDSS spectroscopy, showing that ∼50% of the ETGs have EW(Hα) >6.0 Å. Of the LTGs, 95% show uniform radial color profiles, which can be interpreted as a red bulge plus an extended blue disk. The links between the two kinds of ETGs, e.g., those objects having remarkable ''blue-cores'' and those having flat color gradients, are less known and require future investigations. It is suggested that the LTGs follow a general model by which quenching first occurs in the core regions, and then finally extend to the rest of the galaxy. Our results can be re-examined and have important implications for the IFU surveys, such as MaNGA and SAMI

  17. Color metallography

    International Nuclear Information System (INIS)

    Hasson, Raymond.

    1976-06-01

    After a short introduction explaining the reasons why color metallography was adopted, the various operations involved in this technique are described in turn and illustrated by colored photomicrographs. The sample preparation (cutting, covering) and surface preparation (trimming, polishing, finishing) are described briefly. The operations specific to color metallography are then detailed: revelation of the structure of polished surfaces, dye impregnation techniques, optical systems used in macrography, in micrography, different light sources used in microscopy, photographic methods [fr

  18. Clinical utility of eco-color-power Doppler ultrasonography and contrast enhanced magnetic resonance imaging for interpretation and quantification of joint synovitis: a review.

    Science.gov (United States)

    Carotti, Marina; Galeazzi, Vittoria; Catucci, Francesca; Zappia, Marcello; Arrigoni, Francesco; Barile, Antonio; Giovagnoni, Andrea

    2018-01-19

    With the introduction of new biologics such as anti-TNF-alpha antibodies and other therapies in the treatment of inflammatory arthritis, capable of halting joint destruction and functional disability, there are new pressures on diagnostic and prognostic imaging. Early demonstration of pre-erosive inflammatory features and monitoring of the long-term effects of treatment are becoming increasingly important. Early detection of synovitis offers advantages in terms of allowing early instigation of therapy and may allow the identification of those patients displaying more aggressive disease who might benefit from early intervention with expensive DMARD therapy. Advanced imaging techniques such as ultrasound (US) and magnetic resonance imaging (MRI) have focussed on the demonstration and quantification of synovitis and allow early diagnosis of inflammatory arthropathies such as rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Synovitis represents a potential surrogate measure of disease activity that can be monitored using either MRI or US; the techniques have, generally, focused on monitoring synovial volume or quality as assessed by its vascularity. However to achieve these goals, standardisation and validation of US and MRI are required to ensure accurate diagnosis, reproducibility and reliability. Each modality has different strengths and weaknesses and levels of validation. This article aims to increase the awareness of radiologists and rheumatologists about this field and to encourage them to participate and contribute to the ongoing development of these modalities. Without this collaboration, it is unlikely that these modalities will reach their full potential in the field of rheumatological imaging. This review is in two parts. The first part addresses the role of US and colour or power Doppler sonography (PDUS) in the detection and monitoring of synovitis in inflammatory arthropathies. The second part will look at advanced MR imaging and Dynamic contrast

  19. Optics

    CERN Document Server

    Fincham, W H A

    2013-01-01

    Optics: Ninth Edition Optics: Ninth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommen

  20. Modificações da hemodinâmica fetal pelo estímulo sonoro: avaliação pela dopplervelocimetria colorida Vibro-acoustic stimulation induced hemodynamic fetal changes assessed by color doppler

    Directory of Open Access Journals (Sweden)

    Francisco Mauad Filho

    1999-04-01

    Full Text Available Objetivos: verificar se ocorrem ou não alterações hemodinâmicas na aréria cerebral média (ACM aferido pela dopplervelocimetria colorida após realização de um estímulo sonoro. Métodos: trinta fetos de gestantes consideradas clinicamente normais com idade gestacional igual ou superior a 28 semanas foram submetidos a um estímulo sonoro. Examinamos as alterações da velocidade sangüínea na ACM fetal por meio do índice de resistência e da freqüência cardíaca fetal, pelo doppler colorido, antes e depois do estímulo acústico. Resultados: a média da freqüência cardíaca fetal (FCF antes do estímulo sonoro foi de 142,41 batimentos por minuto (bpm com desvio padrão de 9,01 e faixa de variação de 122 a 162 bpm. Após o estímulo sonoro, a média da FCF foi de 159,44 bpm com desvio padrão de 15,49, com faixa de variação de 130 a 187 bpm (pPurpose: to determine the possible occurrence of hemodynamic changes in the middle cerebral artery of the fetus (MCA using color doppler after vibro-acoustic stimulation. Methods: thirty fetuses from pregnant women considered to be clinically normal, with a gestational age of 28 weeks or more were submitted to vibro-acoustic stimulation. We examined the changes in blood flow rate in the middle cerebral artery of the fetus on the basis of resistance index (RI and fetal heart rate (FHR by color doppler before and after the sound stimulus. Results: mean FHR before vibro-acoustic stimulation was 142.41 beats per minute (bpm with a standard deviation of 9.01 and a range of 122 to 162 bpm. After stimulation, mean FHR was 159.44 bpm with a standard deviation of 15.49 and a range of 130 to 187 bpm (p<0.01. Mean RI in the MCA of the fetuses was 75.89% (range: 64 to 91% before the experiment. After the vibro-acoustic stimulation, mean RI was 66.93% (range: 47 to 83%; p < 0.01. Conclusions: we observed that a sound stimulus provokes the well-known immediate and significant elevation of FHR and a

  1. Laser doppler perfusion imaging

    International Nuclear Information System (INIS)

    Waardell, K.

    1992-01-01

    Recording of tissue perfusion is important in assessing the influence of peripheral vascular diseases on the microcirculation. This thesis reports on a laser doppler perfusion imager based on dynamic light scattering in tissue. When a low power He-Ne laser beam sequentally scans the tissue, moving blood cells generate doppler components in the back-scattered light. A fraction of this light is detected by a photodetector and converted into an electrical signal. In the processor, a signal proportional to the tissue perfusion at each measurement site is calculated and stored. When the scanning procedure is completed, a color-coded perfusion image is presented on a monitor. To convert important aspects of the perfusion image into more quantitative parameters, data analysis functions are implemented in the software. A theory describing the dependence of the distance between individual measurement points and detector on the system amplification factor is proposed and correction algorithms are presented. The performance of the laser doppler perfusion imager was evaluated using a flow simulator. A linear relationship between processor output signal and flow through the simulator was demonstrated for blood cell concentrations below 0.2%. The median sampling depth of the laser beam was simulated by a Monte Carlo technique and estimated to 235 μm. The perfusion imager has been used in the clinic to study perfusion changes in port wine stains treated with argon laser and to investigate the intensity and extension of the cutaneous axon reflex response after electrical nerve stimulation. The fact that perfusion can be visualized without touching the tissue implies elimination of sterilization problems, thus simplifying clinical investigations of perfusion in association with diagnosis and treatment of peripheral vascular diseases. 22 refs

  2. Self-mixing laser Doppler vibrometry with high optical sensitivity application to real-time sound reproduction

    CERN Document Server

    Abe, K; Ko, J Y

    2003-01-01

    Nanometre vibration measurement of an audio speaker and a highly sensitive sound reproduction experiment have been successfully demonstrated by a self-aligned optical feedback vibrometry technique using the self-mixing modulation effect in a laser-diode-pumped microchip solid-state laser. By applying nanometre vibrations to the speaker, which produced nearly inaudible music below 20 dB (200 mu Pa) sound pressure level, we could reproduce clear sound in real time by the use of a simple frequency modulated wave demodulation circuit with a -120 dB light-intensity feedback ratio.

  3. Self-mixing laser Doppler vibrometry with high optical sensitivity: application to real-time sound reproduction

    International Nuclear Information System (INIS)

    Abe, Kazutaka; Otsuka, Kenju; Ko, Jing-Yuan

    2003-01-01

    Nanometre vibration measurement of an audio speaker and a highly sensitive sound reproduction experiment have been successfully demonstrated by a self-aligned optical feedback vibrometry technique using the self-mixing modulation effect in a laser-diode-pumped microchip solid-state laser. By applying nanometre vibrations to the speaker, which produced nearly inaudible music below 20 dB (200 μPa) sound pressure level, we could reproduce clear sound in real time by the use of a simple frequency modulated wave demodulation circuit with a -120 dB light-intensity feedback ratio

  4. Self-mixing laser Doppler vibrometry with high optical sensitivity: application to real-time sound reproduction

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Kazutaka [Department of Human and Information Science, Tokai University, 1117 Kitakaname, Hiratsuka, Kanagawa (Japan); Otsuka, Kenju [Department of Human and Information Science, Tokai University, 1117 Kitakaname, Hiratsuka, Kanagawa (Japan); Ko, Jing-Yuan [Department of Physics, Tunghai University, 181 Taichung-kang Road, Section 3, Taichung 407, Taiwan (China)

    2003-01-01

    Nanometre vibration measurement of an audio speaker and a highly sensitive sound reproduction experiment have been successfully demonstrated by a self-aligned optical feedback vibrometry technique using the self-mixing modulation effect in a laser-diode-pumped microchip solid-state laser. By applying nanometre vibrations to the speaker, which produced nearly inaudible music below 20 dB (200 {mu}Pa) sound pressure level, we could reproduce clear sound in real time by the use of a simple frequency modulated wave demodulation circuit with a -120 dB light-intensity feedback ratio.

  5. A Noninvasive Miniaturized-Wireless Laser-Doppler Fiber-Optic Sensor for Understanding Distal Fingertip Injuries in Astronauts

    Science.gov (United States)

    Ansari, Rafat R.; Jones, Jeffrey A.; Pollonini, Luca; Rodriquez, Mikael; Opperman, Roedolph; Hochstein, Jason

    2009-01-01

    During extra-vehicular activities (EVAs) or spacewalks astronauts over use their fingertips under pressure inside the confined spaces of gloves/space suits. The repetitive hand motion is a probable cause for discomfort and injuries to the fingertips. We describe a new wireless fiber-optic probe that can be integrated inside the astronaut glove for noninvasive blood perfusion measurements in distal fingertips. In this preliminary study, we present blood perfusion measurements while performing hand-grip exercises simulating the use of space tools.

  6. Homogenization of Doppler broadening in spin-noise spectroscopy

    Science.gov (United States)

    Petrov, M. Yu.; Ryzhov, I. I.; Smirnov, D. S.; Belyaev, L. Yu.; Potekhin, R. A.; Glazov, M. M.; Kulyasov, V. N.; Kozlov, G. G.; Aleksandrov, E. B.; Zapasskii, V. S.

    2018-03-01

    The spin-noise spectroscopy, being a nonperturbative linear optics tool, is still reputed to reveal a number of capabilities specific to nonlinear optics techniques. The effect of the Doppler broadening homogenization discovered in this work essentially widens these unique properties of spin-noise spectroscopy. We investigate spin noise of a classical system—cesium atoms vapor with admixture of buffer gas—by measuring the spin-induced Faraday rotation fluctuations in the region of D 2 line. The line, under our experimental conditions, is strongly inhomogeneously broadened due to the Doppler effect. Despite that, optical spectrum of the spin-noise power has the shape typical for the homogeneously broadened line with a dip at the line center. This fact is in stark contrast with the results of previous studies of inhomogeneous quantum dot ensembles and Doppler broadened atomic systems. In addition, the two-color spin-noise measurements have shown, in a highly spectacular way, that fluctuations of the Faraday rotation within the line are either correlated or anticorrelated depending on whether the two wavelengths lie on the same side or on different sides of the resonance. The experimental data are interpreted in the frame of the developed theoretical model which takes into account both kinetics and spin dynamics of Cs atoms. It is shown that the unexpected behavior of the Faraday rotation noise spectra and effective homogenization of the optical transition in the spin-noise measurements are related to smallness of the momentum relaxation time of the atoms as compared with their spin-relaxation time. Our findings demonstrate abilities of spin-noise spectroscopy for studying dynamic properties of inhomogeneously broadened ensembles of randomly moving spins.

  7. Suppressing Structural Colors of Photocatalytic Optical Coatings on Glass: The Critical Role of SiO2.

    Science.gov (United States)

    Li, Ronghua; Boudot, Mickael; Boissière, Cédric; Grosso, David; Faustini, Marco

    2017-04-26

    The appearance of structural colors on coated-glass is a critical esthetical drawback toward industrialization of photocatalytic coatings on windows for architecture or automobile. Herein we describe a rational approach to suppress the structural color of mesoporous TiO 2 -based coatings preserving photoactivity and mechanical stiffness. Addition of SiO 2 as third component is discussed. Ti x Si (1-x) O 2 mesoporous coatings were fabricated by one-step liquid deposition process through the evaporation induced self-assembling and characterized by GI-SAXS, GI-WAXS, electron microscopies, and in situ Environmental Ellipsometry Porosimetry. Guided by optical simulation, we investigated the critical role of SiO 2 on the optical responses of the films but also on the structural, mechanical, and photocatalytic properties, important requirements to go toward real applications. We demonstrate that adding SiO 2 to porous TiO 2 allows tuning and suppression of structural colors through refractive index matching and up to 160% increase in mechanical stiffening of the films. This study leads us to demonstrate an example of "invisible" coating, in which the light reflection is angle- and thickness-independent, and exhibiting high porosity, mechanical stiffness, and photoactivity.

  8. An optical color image watermarking scheme by using compressive sensing with human visual characteristics in gyrator domain

    Science.gov (United States)

    Liansheng, Sui; Bei, Zhou; Zhanmin, Wang; Ailing, Tian

    2017-05-01

    A novel optical color image watermarking scheme considering human visual characteristics is presented in gyrator transform domain. Initially, an appropriate reference image is constructed of significant blocks chosen from the grayscale host image by evaluating visual characteristics such as visual entropy and edge entropy. Three components of the color watermark image are compressed based on compressive sensing, and the corresponding results are combined to form the grayscale watermark. Then, the frequency coefficients of the watermark image are fused into the frequency data of the gyrator-transformed reference image. The fused result is inversely transformed and partitioned, and eventually the watermarked image is obtained by mapping the resultant blocks into their original positions. The scheme can reconstruct the watermark with high perceptual quality and has the enhanced security due to high sensitivity of the secret keys. Importantly, the scheme can be implemented easily under the framework of double random phase encoding with the 4f optical system. To the best of our knowledge, it is the first report on embedding the color watermark into the grayscale host image which will be out of attacker's expectation. Simulation results are given to verify the feasibility and its superior performance in terms of noise and occlusion robustness.

  9. Comparison of optical and power Doppler ultrasound imaging for non-invasive evaluation of arsenic trioxide as a vascular disrupting agent in tumors.

    Science.gov (United States)

    Alhasan, Mustafa K; Liu, Li; Lewis, Matthew A; Magnusson, Jennifer; Mason, Ralph P

    2012-01-01

    Small animal imaging provides diverse methods for evaluating tumor growth and acute response to therapy. This study compared the utility of non-invasive optical and ultrasound imaging to monitor growth of three diverse human tumor xenografts (brain U87-luc-mCherry, mammary MCF7-luc-mCherry, and prostate PC3-luc) growing in nude mice. Bioluminescence imaging (BLI), fluorescence imaging (FLI), and Power Doppler ultrasound (PD US) were then applied to examine acute vascular disruption following administration of arsenic trioxide (ATO).During initial tumor growth, strong correlations were found between manual caliper measured tumor volume and FLI intensity, BLI intensity following luciferin injection, and traditional B-mode US. Administration of ATO to established U87 tumors caused significant vascular shutdown within 2 hrs at all doses in the range 5 to 10 mg/kg in a dose dependant manner, as revealed by depressed bioluminescent light emission. At lower doses substantial recovery was seen within 4 hrs. At 8 mg/kg there was >85% reduction in tumor vascular perfusion, which remained depressed after 6 hrs, but showed some recovery after 24 hrs. Similar response was observed in MCF7 and PC3 tumors. Dynamic BLI and PD US each showed similar duration and percent reductions in tumor blood flow, but FLI showed no significant changes during the first 24 hrs.The results provide further evidence for comparable utility of optical and ultrasound imaging for monitoring tumor growth, More specifically, they confirm the utility of BLI and ultrasound imaging as facile assays of the vascular disruption in solid tumors based on ATO as a model agent.

  10. Assessment of Optical Coherence Tomography Color Probability Codes in Myopic Glaucoma Eyes After Applying a Myopic Normative Database.

    Science.gov (United States)

    Seol, Bo Ram; Kim, Dong Myung; Park, Ki Ho; Jeoung, Jin Wook

    2017-11-01

    To evaluate the optical coherence tomography (OCT) color probability codes based on a myopic normative database and to investigate whether the implementation of the myopic normative database can improve the OCT diagnostic ability in myopic glaucoma. Comparative validity study. In this study, 305 eyes (154 myopic healthy eyes and 151 myopic glaucoma eyes) were included. A myopic normative database was obtained based on myopic healthy eyes. We evaluated the agreement between OCT color probability codes after applying the built-in and myopic normative databases, respectively. Another 120 eyes (60 myopic healthy eyes and 60 myopic glaucoma eyes) were included and the diagnostic performance of OCT color codes using a myopic normative database was investigated. The mean weighted kappa (Kw) coefficients for quadrant retinal nerve fiber layer (RNFL) thickness, clock-hour RNFL thickness, and ganglion cell-inner plexiform layer (GCIPL) thickness were 0.636, 0.627, and 0.564, respectively. The myopic normative database showed a higher specificity than did the built-in normative database in quadrant RNFL thickness, clock-hour RNFL thickness, and GCIPL thickness (P database in quadrant RNFL thickness, clock-hour RNFL thickness, and GCIPL thickness (P = .011, P = .004, P database. The implementation of a myopic normative database is needed to allow more precise interpretation of OCT color probability codes when used in myopic eyes. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Color Fundus Photography, Optical Coherence Tomography, and Fluorescein Angiography in Diagnosing Polypoidal Choroidal Vasculopathy.

    Science.gov (United States)

    Chaikitmongkol, Voraporn; Khunsongkiet, Preeyanuch; Patikulsila, Direk; Ratanasukon, Mansing; Watanachai, Nawat; Jumroendararasame, Chaisiri; Mayerle, Catherine B; Han, Ian C; Chen, Connie J; Winaikosol, Pawara; Dejkriengkraikul, Chutikarn; Choovuthayakorn, Janejit; Kunavisarut, Paradee; Bressler, Neil M

    2018-05-10

    To determine sensitivity and specificity of polypoidal choroidal vasculopathy (PCV) diagnosis using color fundus photography (CFP), optical coherence tomography (OCT) and fundus fluorescein angiography (FFA) without indocyanine-green angiography (ICGA). Validity analysis. Treatment-naïve eyes with serous/serosanguinous maculopathy undergoing CFP, OCT, FFA and ICGA imaging before treatment at a university-hospital in Thailand (January 2013 to June 2015) were identified. Images of each subject were categorized into 4 sets (set A: CFP; set B: CFP+OCT; set C: CFP+FFA; set D: CFP+OCT+FFA). Six graders, 3 from Thailand (PCV endemic area) and 3 from U.S. (non-endemic area), individually reviewed each set (without ICG), and determined if the presumed diagnosis was PCV. In parallel, 2 other graders confirmed if each case had PCV or not using EVEREST criteria (including ICGA). Sensitivity and specificity of a PCV diagnosis with each set (without ICGA) were analyzed compared with diagnoses including ICGA. Of 119 study eyes (113 subjects, 57% male, mean age±SD 59.9±13.8), definite PCV diagnosis was 40.3%. Sensitivity of sets A, B, C, D: 0.63 (95%CI: 0.47-0.76), 0.83 (95%CI: 0.69-0.92), 0.54 (95%CI: 0.39-0.68), 0.67 (95%CI: 0.51-0.79). Specificity were 0.93 (95% CI: 0.84-0.97), 0.83 (95%CI: 0.72-0.91), 0.97 (95%CI: 0.89-0.99), 0.92 (95%CI: 0.82-0.97). Accuracies: 0.81 (95%CI: 0.73-0.88), 0.83 (95%CI: 0.76-0.90), 0.79 (95%CI: 0.73-0.87), 0.82 (95%CI: 0.74-0.88). Discrepancies between Thai and US graders existed through sets A, C, and D. These data suggest without ICGA, fundus photography combined with OCT provides high sensitivity and high specificity to diagnosis PCV; adding FFA does not improve accuracy. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Optics

    CERN Document Server

    Fincham, W H A

    2013-01-01

    Optics: Eighth Edition covers the work necessary for the specialization in such subjects as ophthalmic optics, optical instruments and lens design. The text includes topics such as the propagation and behavior of light; reflection and refraction - their laws and how different media affect them; lenses - thick and thin, cylindrical and subcylindrical; photometry; dispersion and color; interference; and polarization. Also included are topics such as diffraction and holography; the limitation of beams in optical systems and its effects; and lens systems. The book is recommended for engineering st

  13. Three-color photometry of HDE 226868: The optical counterpart of cygnus X-1

    International Nuclear Information System (INIS)

    Lester, D.F.; Nolt, I.G.; Stearns, S.A.; Straton, P.; Radostitz, J.V.

    1976-01-01

    The results of UBV photoelectric observations of HDE 226868 (Cyg X-1) obtained on fifty nights during 1974 are presented. These observations show a light curve with the following characteristics: two unequal light maxima and minima during the 5/sup d/.6 orbital period which exhibit a peak-to-peak magnitude change of approx.0.07 mag in all colors;a small phase-dependent color variation which results in a reddening in both color indices of approx.0.003 mag at times of light minima; erratic light variability on a general time scale of days with an amplitude of +- 0.01 to 0.02 mag and no apparent color dependence

  14. Exemplar-based optical neural net classifier for color pattern recognition

    Science.gov (United States)

    Yu, Francis T. S.; Uang, Chii-Maw; Yang, Xiangyang

    1992-10-01

    We present a color exemplar-based neural network that can be used as an optimum image classifier or an associative memory. Color decomposition and composition technique is used for constructing the polychromatic interconnection weight matrix (IWM). The Hamming net algorithm is modified to relax the dynamic range requirement of the spatial light modulator and to reduce the number of iteration cycles in the winner-take-all layer. Computer simulation results demonstrated the feasibility of this approach

  15. Neuromorphic optical sensor chip with color change-intensity change disambiguation

    Science.gov (United States)

    Fu, ZhenHong; Mao, Rui; Cartwright, Alexander N.; Titus, Albert H.

    2010-02-01

    In this paper, we describe the development of a novel, retina-like neuromorphic chip that has an array of two types of retina 'cells' arranged to mimic the fovea structure in certain animals. One of the two retina cell types performs irradiance detection and the other can perform color detection. Together, via the two parallel pathways the retina chip can perform color change intensity change disambiguation (CCICD). The irradiance detection cell has a wide-dynamic detection range that spans almost 3 orders of magnitude. The color detection cell has a buried double junction (BDJ) photodiode as the photoreceptor followed by two parallel logarithmic I-V convertors. The output from this is a color response which has at least a 50nm resolution for wavelengths from 400nm to 900nm. With these two cells, the array can perform color change -intensity change disambiguation (CCICD) to determine if a change in the output of the irradiance pathway is because of irradiance change, color change, or both. This biological retina-like neuromorphic sensor array is implemented in ON-SEMI 0.5μm technology, a standard CMOS fabrication process available at MOSIS.

  16. An overview of approaches and challenges for retrieving marine inherent optical properties from ocean color remote sensing

    Science.gov (United States)

    Werdell, P. Jeremy; McKinna, Lachlan I. W.; Boss, Emmanuel; Ackleson, Steven G.; Craig, Susanne E.; Gregg, Watson W.; Lee, Zhongping; Maritorena, Stéphane; Roesler, Collin S.; Rousseaux, Cécile S.; Stramski, Dariusz; Sullivan, James M.; Twardowski, Michael S.; Tzortziou, Maria; Zhang, Xiaodong

    2018-01-01

    Ocean color measured from satellites provides daily global, synoptic views of spectral water-leaving reflectances that can be used to generate estimates of marine inherent optical properties (IOPs). These reflectances, namely the ratio of spectral upwelled radiances to spectral downwelled irradiances, describe the light exiting a water mass that defines its color. IOPs are the spectral absorption and scattering characteristics of ocean water and its dissolved and particulate constituents. Because of their dependence on the concentration and composition of marine constituents, IOPs can be used to describe the contents of the upper ocean mixed layer. This information is critical to further our scientific understanding of biogeochemical oceanic processes, such as organic carbon production and export, phytoplankton dynamics, and responses to climatic disturbances. Given their importance, the international ocean color community has invested significant effort in improving the quality of satellite-derived IOP products, both regionally and globally. Recognizing the current influx of data products into the community and the need to improve current algorithms in anticipation of new satellite instruments (e.g., the global, hyperspectral spectroradiometer of the NASA Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission), we present a synopsis of the current state of the art in the retrieval of these core optical properties. Contemporary approaches for obtaining IOPs from satellite ocean color are reviewed and, for clarity, separated based their inversion methodology or the type of IOPs sought. Summaries of known uncertainties associated with each approach are provided, as well as common performance metrics used to evaluate them. We discuss current knowledge gaps and make recommendations for future investment for upcoming missions whose instrument characteristics diverge sufficiently from heritage and existing sensors to warrant reassessing current approaches.

  17. Color doppler evaluation of the influence of type of delivery, sex, postnatal age and time post feeding on full term healthy newborns cerebral blood flow Doppler colorido na avaliação da influência do tipo de parto, sexo, idade pós-natal e tempo pós-mamada no fluxo sanguíneo cerebral em recém-nascidos a termo e saudáveis

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Aranha

    2009-06-01

    Full Text Available OBJECTIVE: The purpose of this study was to evaluate with Color Doppler the influence of type of delivery, sex, postnatal age and time post feeding on full term healthy newborns cerebral blood flow. METHOD: 50 newborns were studied. The Doppler parameters, peak-systolic velocity, end-diastolic velocity, mean velocity, pulsatility index and resistance index, were measured in the anterior cerebral artery, middle cerebral artery, posterior cerebral artery, and basilar artery. The data were compared and analyzed by statistical tests. Informed consent was obtained from all parents, and the study was approved by institutional ethical committee and review board. RESULTS: We observed not statistically significant differences on cerebral blood flow Doppler parameters in relation to type of delivery, sex, postnatal age and feeding in full term healthy newborns. CONCLUSION: We believe that the knowledge of these cerebral hemodynamic profile of newborns in the first days of life can contribute in an accurate interpretation of cranial Doppler abnormal findings when pathologic flow velocities are analyzed.OBJETIVO: O objetivo deste estudo foi avaliar com Doppler colorido a influência do tipo de parto, sexo, idade pós-natal e tempo pós-mamada no fluxo sanguíneo cerebral de recém-nascidos a termo e saudáveis. MÉTODO: Foram estudados 50 recém-nascidos. A Dopplervelocimetria foi obtida nas artérias cerebral anterior, cerebral média, cerebral posterior e basilar. Os parâmetros foram comparados e analisados pelos testes estatísticos Esta pesquisa foi aprovada pela comissão ética e de pós-graduação das instituições e o consentimento informado dos pais foi obtido em todos os casos. RESULTADOS: Não observamos diferenças estatísticamente significativas na Dopplervelocimetria do fluxo sanguíneo cerebral em relação ao tipo de parto, sexo, idade pós-natal e tempo pós-mamada dos recém-nascidos normais e saudáveis estudados. CONCLUS

  18. Molecules cooled below the Doppler limit

    Science.gov (United States)

    Truppe, S.; Williams, H. J.; Hambach, M.; Caldwell, L.; Fitch, N. J.; Hinds, E. A.; Sauer, B. E.; Tarbutt, M. R.

    2017-12-01

    Magneto-optical trapping and sub-Doppler cooling have been essential to most experiments with quantum degenerate gases, optical lattices, atomic fountains and many other applications. A broad set of new applications await ultracold molecules, and the extension of laser cooling to molecules has begun. A magneto-optical trap (MOT) has been demonstrated for a single molecular species, SrF, but the sub-Doppler temperatures required for many applications have not yet been reached. Here we demonstrate a MOT of a second species, CaF, and we show how to cool these molecules to 50 μK, well below the Doppler limit, using a three-dimensional optical molasses. These ultracold molecules could be loaded into optical tweezers to trap arbitrary arrays for quantum simulation, launched into a molecular fountain for testing fundamental physics, and used to study collisions and chemistry between atoms and molecules at ultracold temperatures.

  19. Encyclopedia of color science and technology

    CERN Document Server

    2016-01-01

    The Encyclopedia of Color Science and Technology provides an authoritative single source for understanding and applying the concepts of color to all fields of science and technology, including artistic and historical aspects of color. Many topics are discussed in this timely reference, including an introduction to the science of color, and entries on the physics, chemistry and perception of color. Color is described as it relates to optical phenomena of color and continues on through colorants and materials used to modulate color and also to human vision of color. The measurement of color is provided as is colorimetry, color spaces, color difference metrics, color appearance models, color order systems and cognitive color. Other topics discussed include industrial color, color imaging, capturing color, displaying color and printing color. Descriptions of color encodings, color management, processing color and applications relating to color synthesis for computer graphics are included in this work. The Encyclo...

  20. Full-color, large area, transmissive holograms enabled by multi-level diffractive optics.

    Science.gov (United States)

    Mohammad, Nabil; Meem, Monjurul; Wan, Xiaowen; Menon, Rajesh

    2017-07-19

    We show that multi-level diffractive microstructures can enable broadband, on-axis transmissive holograms that can project complex full-color images, which are invariant to viewing angle. Compared to alternatives like metaholograms, diffractive holograms utilize much larger minimum features (>10 µm), much smaller aspect ratios (30 mm ×30 mm). We designed, fabricated and characterized holograms that encode various full-color images. Our devices demonstrate absolute transmission efficiencies of >86% across the visible spectrum from 405 nm to 633 nm (peak value of about 92%), and excellent color fidelity. Furthermore, these devices do not exhibit polarization dependence. Finally, we emphasize that our devices exhibit negligible absorption and are phase-only holograms with high diffraction efficiency.

  1. Color vision versus pattern visual evoked potentials in the assessment of subclinical optic pathway involvement in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Fatih C Gundogan

    2013-01-01

    Full Text Available Background: Optic pathway involvement in multiple sclerosis is frequently the initial sign in the disease process. In most clinical applications, pattern visual evoked potential (PVEP is used in the assessment of optic pathway involvement. Objective: To question the value of PVEP against color vision assessment in the diagnosis of subclinical optic pathway involvement. Materials and Methods: This prospective, cross-sectional study included 20 multiple sclerosis patients without a history of optic neuritis, and 20 healthy control subjects. Farnsworth-Munsell (FM 100-Hue testing and PVEPs to 60-min arc and 15-min arc checks by using Roland-Consult RetiScan® system were performed. P 100 amplitude, P 100 latency in PVEP and total error scores (TES in FM 100-Hue test were assessed. Results: Expanded Disability Status Scale score and the time from diagnosis were 2.21 ± 2.53 (ranging from 0 to 7 and 4.1 ± 4.4 years. MS group showed significantly delayed P 100 latency for both checks (P 0.05 for all. 14 MS patients (70% had an increased TESs in FM-100 Hue, 11 (55% MS patients had delayed P 100 latency and 9 (45% had reduced P 100 amplitude. The areas under the ROC curves were 0.944 for FM-100 Hue test, 0.753 for P 100 latency, and 0.173 for P 100 amplitude. Conclusions: Color vision testing seems to be more sensitive than PVEP in detecting subclinical visual pathway involvement in MS.

  2. [Postpartal ovarian thrombophlebitis. Value of Doppler ultrasonograph y].

    Science.gov (United States)

    Renaud-Giono, A; Giraud, J R; Poulain, P; Proudhon, J F; Grall, J Y; Moquet, P Y; Darnault, J P

    1996-01-01

    Thrombophlebitis of the ovarian vein is a well recognized but uncommon complication during the postpartum period. We report a small series and emphasize the contribution of color Doppler and the basic therapeutic measures.

  3. Color-Coded Batteries - Electro-Photonic Inverse Opal Materials for Enhanced Electrochemical Energy Storage and Optically Encoded Diagnostics.

    Science.gov (United States)

    O'Dwyer, Colm

    2016-07-01

    For consumer electronic devices, long-life, stable, and reasonably fast charging Li-ion batteries with good stable capacities are a necessity. For exciting and important advances in the materials that drive innovations in electrochemical energy storage (EES), modular thin-film solar cells, and wearable, flexible technology of the future, real-time analysis and indication of battery performance and health is crucial. Here, developments in color-coded assessment of battery material performance and diagnostics are described, and a vision for using electro-photonic inverse opal materials and all-optical probes to assess, characterize, and monitor the processes non-destructively in real time are outlined. By structuring any cathode or anode material in the form of a photonic crystal or as a 3D macroporous inverse opal, color-coded "chameleon" battery-strip electrodes may provide an amenable way to distinguish the type of process, the voltage, material and chemical phase changes, remaining capacity, cycle health, and state of charge or discharge of either existing or new materials in Li-ion or emerging alternative battery types, simply by monitoring its color change. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Optics: Light, Color, and Their Uses. An Educator's Guide With Activities In Science and Mathematics

    Science.gov (United States)

    2000-01-01

    This document includes information on the Chandra X-Ray Observatory, the Hubble Space Telescope, the Next Generation Space Telescope, Soft X-Ray Imager, and the Lightning Imaging System. Classroom activities from grades K-12 are included, focusing on light and color, using mirrors, lenses, prisms, and filters.

  5. MULTI-COLOR OPTICAL AND NEAR-INFRARED LIGHT CURVES OF 64 STRIPPED-ENVELOPE CORE-COLLAPSE SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Bianco, F. B.; Modjaz, M. [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Hicken, M.; Friedman, A.; Kirshner, R. P.; Challis, P.; Marion, G. H. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Bloom, J. S. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Wood-Vasey, W. M. [PITT PACC, Department of Physics and Astronomy, 3941 O' Hara Street, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Rest, A., E-mail: fb55@nyu.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2014-08-01

    We present a densely sampled, homogeneous set of light curves of 64 low-redshift (z ≲ 0.05) stripped-envelope supernovae (SNe of Type IIb, Ib, Ic, and Ic-BL). These data were obtained between 2001 and 2009 at the Fred L. Whipple Observatory (FLWO) on Mount Hopkins in Arizona, with the optical FLWO 1.2 m and the near-infrared (NIR) Peters Automated Infrared 1.3 m telescopes. Our data set consists of 4543 optical photometric measurements on 61 SNe, including a combination of U BV RI, U BV r{sup ′}i{sup ′}, and u{sup ′} BV r{sup ′}i{sup ′}, and 1919 JHK{sub s} NIR measurements on 25 SNe. This sample constitutes the most extensive multi-color data set of stripped-envelope SNe to date. Our photometry is based on template-subtracted images to eliminate any potential host-galaxy light contamination. This work presents these photometric data, compares them with data in the literature, and estimates basic statistical quantities: date of maximum, color, and photometric properties. We identify promising color trends that may permit the identification of stripped-envelope SN subtypes from their photometry alone. Many of these SNe were observed spectroscopically by the Harvard-Smithsonian Center for Astrophysics (CfA) SN group, and the spectra are presented in a companion paper. A thorough exploration that combines the CfA photometry and spectroscopy of stripped-envelope core-collapse SNe will be presented in a follow-up paper.

  6. Two-color interpolation of the absorption response for quantitative acousto-optic imaging

    DEFF Research Database (Denmark)

    Bocoum, Maimouna; Gennisson, Jean Luc; Venet, Caroline

    2018-01-01

    Diffuse optical tomography (DOT) is a reliable and widespread technique for monitoring qualitative changes in absorption inside highly scattering media. It has been shown, however, that acousto-optic (AO) imaging can provide significantly more qualitative information without the need for inversio...

  7. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Maulik, D. [Winthrop Univ. Hospital, Mineola, NY (United States). Dept. of Obstetrics and Gynecology; Zalud, I. (eds.) [Kapiolani Medical Center for Women and Children, Honolulu, HI (United States)

    2005-07-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  8. Doppler ultrasound in obstetrics and gynecology. 2. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Maulik, D.

    2005-01-01

    The second edition of Doppler Ultrasound in Obstetrics and Gynecology has been expanded and comprehensively updated to present the current standards of practice in Doppler ultrasound and the most recent developments in the technology. Doppler Ultrasound in Obstetrics and Gynecology encompasses the full spectrum of clinical applications of Doppler ultrasound for the practicing obstetrician-gynecologist, including the latest advances in 3D and color Doppler and the newest techniques in 4D fetal echocardiography. Written by preeminent experts in the field, the book covers the basic and physical principles of Doppler ultrasound; the use of Doppler for fetal examination, including fetal cerebral circulation; Doppler echocardiography of the fetal heart; and the use of Doppler for postdated pregnancy and in cases of multiple gestation. Chapters on the use of Doppler for gynecologic investigation include ultrasound in ectopic pregnancy, for infertility, for benign disorders and for gynecologic malignancies. (orig.)

  9. Estudo dopplerfluxométrico das artérias uterinas antes e após inserção do DIU Color doppler flow analysis of the uterine arteries before and after DIU insertion

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Martins de Souza

    2004-06-01

    Full Text Available OBJETIVO: averiguar se ocorrem alterações nos parâmetros da dopplervelocimetria em usuárias do dispositivo intra-uterino (DIU T cobre 380, por meio do estudo das artérias uterinas antes e depois da inserção do DIU em mulheres lactantes e não lactantes. MÉTODOS: ensaio clínico prospectivo, analítico, com 100 pacientes, em que avaliamos à dopplervelocimetria: índice de resistência (IR, índice de pulsatilidade (IP e relação sístole/diástole (SD. As pacientes selecionadas foram submetidas à avaliação pré-inserção do DIU e a novos exames pós-inserção, realizados com 30 dias (um ciclo e com 90 dias (três ciclos. RESULTADOS: os valores obtidos nas artérias uterinas no grupo antes da inserção do DIU foram de 0,9 para o IR, de 2,4 para o IP e de 10,0 para a relação SD. Os valores 30 dias após a inserção do DIU foram de 0,9 para o IR, de 2,5 para o IP e de 10,7 para a relação SD. Após três ciclos aferimos um valor de 0,9 para o IR, de 2,5 para o IP e de 10,7 para a relação SD. A comparação dos resultados obtidos antes e depois da inserção do DIU mostrou valor p de 0,51 para o IR, de 0,37 para o IP e de 0,51 para a relação SD, demonstrando que após a inserção, não houve modificações significativas na dopplervelocimetria. CONCLUSÕES: o uso do DIU T cobre 380 não tem efeito nos índices de dopplervelocimetria das artérias uterinas tanto em pacientes amamentando ou não.OBJECTIVE: to observe if there is any alteration in the Dopplervelocimetry of the uterine arteries of nursing and not nursing women after the insertion of the copper T 380 intrauterine device (IUD. METHODS: prospective, analytical, self-paired clinical assay, with 100 patients in whom we evaluated the color doppler flow: resistance index (RI, pulsative index (PI and systole/diastole (SD ratio. Nursing and not nursing women were assessed before IUD insertion as well as 30 days (one cycle and 90 days (three cycles after the insertion

  10. Phenomenological marine snow model for optical underwater image simulation: Applications to color restoration

    OpenAIRE

    Boffety , Matthieu; Galland , Frédéric

    2012-01-01

    International audience; Optical imaging plays an important role in oceanic science and engineering. However, the design of optical systems and image processing techniques for subsea environment are challenging tasks due to water turbidity. Marine snow is notably a major source of image degradation as it creates white bright spots that may strongly impact the performance of image processing methods. In this context, it is necessary to have a tool to foresee the behavior of these methods in mar...

  11. Calculation of optical properties of dental composites as a basis for determining color impression and penetration depth of laser light

    Science.gov (United States)

    Weniger, Kirsten K.; Muller, Gerhard J.

    2005-03-01

    In order to achieve esthetic dental restorations, there should be no visible difference between restorative material and treated teeth. This requires a match of the optical properties of both restorative material and natural teeth. These optical properties are determined by absorption and scattering of light emerging not only on the surface but also inside the material. Investigating different dental composites in several shades, a method has been developed to calculate the optical parameters absorption coefficient μa, scattering coefficient μs, anisotropy factor g and reduced scattering coefficient μs'. The method includes sample preparation and measurements of transmittance and reflectance in an integrating sphere spectrometer, followed by inverse Monte Carlo simulations. Determination of optical properties is more precise and comprehensive than with the previously used Kubelka Munk theory because scattering can be looked at separated into pure scattering with the scattering coefficient μs and its direction with the anisotropy factor g. Moreover the use of the inverse Monte Carlo simulation not only minimizes systematic errors and considers the scattering phase function, but also takes into account the measuring geometry. The compilation of a data pool of optical parameters now enables the application of further calculation models as a basis for optimization of the composition of new materials. For example, a prediction of the general color impression for multiple layers can be carried out as well as the calculation of the wavelength dependent penetration depths of light with regard to photo polymerization. Further applications are possible in the area of laser ablation.

  12. SDSS QUASARS IN THE WISE PRELIMINARY DATA RELEASE AND QUASAR CANDIDATE SELECTION WITH OPTICAL/INFRARED COLORS

    International Nuclear Information System (INIS)

    Wu Xuebing; Hao Guoqiang; Jia Zhendong; Zhang Yanxia; Peng Nanbo

    2012-01-01

    We present a catalog of 37,842 quasars in the Sloan Digital Sky Survey (SDSS) Data Release 7, which have counterparts within 6'' in the Wide-field Infrared Survey Explorer (WISE) Preliminary Data Release. The overall WISE detection rate of the SDSS quasars is 86.7%, and it decreases to less than 50.0% when the quasar magnitude is fainter than i = 20.5. We derive the median color-redshift relations based on this SDSS-WISE quasar sample and apply them to estimate the photometric redshifts of the SDSS-WISE quasars. We find that by adding the WISE W1- and W2-band data to the SDSS photometry we can increase the photometric redshift reliability, defined as the percentage of sources with photometric and spectroscopic redshift difference less than 0.2, from 70.3% to 77.2%. We also obtain the samples of WISE-detected normal and late-type stars with SDSS spectroscopy, and present a criterion in the z – W1 versus g – z color-color diagram, z – W1 > 0.66(g – z) + 2.01, to separate quasars from stars. With this criterion we can recover 98.6% of 3089 radio-detected SDSS-WISE quasars with redshifts less than four and overcome the difficulty in selecting quasars with redshifts between 2.2 and 3 from SDSS photometric data alone. We also suggest another criterion involving the WISE color only, W1 – W2 > 0.57, to efficiently separate quasars with redshifts less than 3.2 from stars. In addition, we compile a catalog of 5614 SDSS quasars detected by both WISE and UKIDSS surveys and present their color-redshift relations in the optical and infrared bands. By using the SDSS ugriz, UKIDSS, YJHK, and WISE W1- and W2-band photometric data, we can efficiently select quasar candidates and increase the photometric redshift reliability up to 87.0%. We discuss the implications of our results on the future quasar surveys. An updated SDSS-WISE quasar catalog consisting of 101,853 quasars with the recently released WISE all-sky data is also provided.

  13. Cooperative effects between color centers in diamond: applications to optical tweezers and optomechanics

    Science.gov (United States)

    Bradac, Carlo; Prasanna Venkatesh, B.; Besga, Benjamin; Johnsson, Mattias; Brennen, Gavin; Molina-Terriza, Gabriel; Volz, Thomas; Juan, Mathieu L.

    2017-08-01

    Since the early work by Ashkin in 1970,1 optical trapping has become one of the most powerful tools for manipulating small particles, such as micron sized beads2 or single atoms.3 Interestingly, both an atom and a lump of dielectric material can be manipulated through the same mechanism: the interaction energy of a dipole and the electric field of the laser light. In the case of atom trapping, the dominant contribution typically comes from the allowed optical transition closest to the laser wavelength while it is given by the bulk polarisability for mesoscopic particles. This difference lead to two very different contexts of applications: one being the trapping of small objects mainly in biological settings,4 the other one being dipole traps for individual neutral atoms5 in the field of quantum optics. In this context, solid state artificial atoms present the interesting opportunity to combine these two aspects of optical manipulation. We are particularly interested in nanodiamonds as they constitute a bulk dielectric object by themselves, but also contain artificial atoms such as nitrogen-vacancy (NV) or silicon-vacancy (SiV) colour centers. With this system, both regimes of optical trapping can be observed at the same time even at room temperature. In this work, we demonstrate that the resonant force from the optical transition of NV centres at 637 nm can be measured in a nanodiamond trapped in water. This additional contribution to the total force is significant, reaching up to 10%. In addition, due to the very large density of NV centres in a sub-wavelength crystal, collective effects between centres have an important effect on the magnitude of the resonant force.6 The possibility to observe such cooperatively enhanced optical force at room temperature is also theoretically confirmed.7 This approach may enable the study of cooperativity in various nanoscale solid-state systems and the use of atomic physics techniques in the field of nano-manipulation and opto-mechanics.

  14. MODIS Aqua Optical Throughput Degradation Impact on Relative Spectral Response and Calibration on Ocean Color Products

    Science.gov (United States)

    Lee, Shihyan; Meister, Gerhard

    2017-01-01

    Since Moderate Resolution Imaging Spectroradiometer Aqua's launch in 2002, the radiometric system gains of the reflective solar bands have been degrading, indicating changes in the systems optical throughput. To estimate the optical throughput degradation, the electronic gain changes were estimated and removed from the measured system gain. The derived optical throughput degradation shows a rate that is much faster in the shorter wavelengths than the longer wavelengths. The wavelength-dependent optical throughput degradation modulated the relative spectral response (RSR) of the bands. In addition, the optical degradation is also scan angle-dependent due to large changes in response versus the scan angle over time. We estimated the modulated RSR as a function of time and scan angles and its impacts on sensor radiometric calibration for the ocean science. Our results show that the calibration bias could be up to 1.8 % for band 8 (412 nm) due to its larger out-of-band response. For the other ocean bands, the calibration biases are much smaller with magnitudes at least one order smaller.

  15. THE UV–OPTICAL COLOR GRADIENTS IN STAR-FORMING GALAXIES AT 0.5 < z < 1.5: ORIGINS AND LINK TO GALAXY ASSEMBLY

    International Nuclear Information System (INIS)

    Liu, F. S.; Jiang, Dongfei; Li, Yao; Li, Dingpeng; Guo, Yicheng; Koo, David C.; Faber, S. M.; Yesuf, Hassen M.; Barro, Guillermo; Fang, Jerome J.; Zheng, Xianzhong; Wang, Weichen; Mao, Shude

    2016-01-01

    The rest-frame UV–optical (i.e., NUV − B ) color index is sensitive to the low-level recent star formation and dust extinction, but it is insensitive to the metallicity. In this Letter, we have measured the rest-frame NUV − B color gradients in ∼1400 large ( r _e > 0.″18), nearly face-on ( b / a > 0.5) main sequence star-forming galaxies (SFGs) between redshift 0.5 and 1.5 in the CANDELS/GOODS-S and UDS fields. With this sample, we study the origin of UV–optical color gradients in the SFGs at z ∼ 1 and discuss their link with the buildup of stellar mass. We find that the more massive, centrally compact, and more dust extinguished SFGs tend to have statistically more negative raw color gradients (redder centers) than the less massive, centrally diffuse, and less dusty SFGs. After correcting for dust reddening based on optical-spectral energy distribution fitting, the color gradients in the low-mass ( M _* 10"1"0"."5 M _⊙) SFGs still retain shallow negative color gradients. These findings imply that dust reddening is likely the principal cause of negative color gradients in the low-mass SFGs, while both increased central dust reddening and buildup of compact old bulges are likely the origins of negative color gradients in the high-mass SFGs. These findings also imply that at these redshifts the low-mass SFGs buildup their stellar masses in a self-similar way, while the high-mass SFGs grow inside out.

  16. Automated Detection of Glaucoma From Topographic Features of the Optic Nerve Head in Color Fundus Photographs.

    Science.gov (United States)

    Chakrabarty, Lipi; Joshi, Gopal Datt; Chakravarty, Arunava; Raman, Ganesh V; Krishnadas, S R; Sivaswamy, Jayanthi

    2016-07-01

    To describe and evaluate the performance of an automated CAD system for detection of glaucoma from color fundus photographs. Color fundus photographs of 2252 eyes from 1126 subjects were collected from 2 centers: Aravind Eye Hospital, Madurai and Coimbatore, India. The images of 1926 eyes (963 subjects) were used to train an automated image analysis-based system, which was developed to provide a decision on a given fundus image. A total of 163 subjects were clinically examined by 2 ophthalmologists independently and their diagnostic decisions were recorded. The consensus decision was defined to be the clinical reference (gold standard). Fundus images of eyes with disagreement in diagnosis were excluded from the study. The fundus images of the remaining 314 eyes (157 subjects) were presented to 4 graders and their diagnostic decisions on the same were collected. The performance of the system was evaluated on the 314 images, using the reference standard. The sensitivity and specificity of the system and 4 independent graders were determined against the clinical reference standard. The system achieved an area under receiver operating characteristic curve of 0.792 with a sensitivity of 0.716 and specificity of 0.717 at a selected threshold for the detection of glaucoma. The agreement with the clinical reference standard as determined by Cohen κ is 0.45 for the proposed system. This is comparable to that of the image-based decisions of 4 ophthalmologists. An automated system was presented for glaucoma detection from color fundus photographs. The overall evaluation results indicated that the presented system was comparable in performance to glaucoma classification by a manual grader solely based on fundus image examination.

  17. The Value Of Different Standards And Measurement Systems To Determine The Optical Properties Of Paper And For Standardized Color Reproduction

    Science.gov (United States)

    Sobotica, Werner

    1990-06-01

    Several terms are used to determine the optical properties of paper and board. Brightness, whiteness, diffuse reflectance factor, diffuse blue reflectance factor, specular gloss, spectral reflectivity and whiteness and yellowness are the used terms. The mainly used term is brightness of paper, an important property in many specifications, but this property has no visual perceptual foundation. Instead it is based on the filter chosen to measure the reflectance of pulp in the region most sensitive to the effects, of bleaching. Therefore an increasing demand for a specification of whiteness can be observed. Belonging to the concept of color, whiteness has to be measured and interpreted in the scope of CIE (Commission Internationale l'Eclairage) based on colorimetri tristimulus data transformed to agree with the perceptual assessment of whiteness. Human observers differentiate between the whiteness of the object being viewed and its brightness. A special index of whiteness is needed. No general agreement was so far reached regarding the best index which could and should be adopted universally among the two recommended by the CIE. Nearly every white sample is a little colored, having bluish, greenish or redish tint. In the post no numerical measure of tint was assigned to any of the whiteness indexes. Further problems arise that fluorescent whiteness agents are added to paper and board to increase their whiteness. This requires not only instrumental design and calibration but also the illuminant to be adopted for such measurements.

  18. Doppler time-of-flight imaging

    KAUST Repository

    Heide, Felix

    2015-07-30

    Over the last few years, depth cameras have become increasingly popular for a range of applications, including human-computer interaction and gaming, augmented reality, machine vision, and medical imaging. Many of the commercially-available devices use the time-of-flight principle, where active illumination is temporally coded and analyzed on the camera to estimate a per-pixel depth map of the scene. In this paper, we propose a fundamentally new imaging modality for all time-of-flight (ToF) cameras: per-pixel velocity measurement. The proposed technique exploits the Doppler effect of objects in motion, which shifts the temporal frequency of the illumination before it reaches the camera. Using carefully coded illumination and modulation frequencies of the ToF camera, object velocities directly map to measured pixel intensities. We show that a slight modification of our imaging system allows for color, depth, and velocity information to be captured simultaneously. Combining the optical flow computed on the RGB frames with the measured metric axial velocity allows us to further estimate the full 3D metric velocity field of the scene. We believe that the proposed technique has applications in many computer graphics and vision problems, for example motion tracking, segmentation, recognition, and motion deblurring.

  19. TRUE COLORS: LEDS AND THE RELATIONSHIP BETWEEN CCT, CRI, OPTICAL SAFETY, MATERIAL DEGRADATION, AND PHOTOBIOLOGICAL STIMULATION

    Energy Technology Data Exchange (ETDEWEB)

    Royer, Michael P.

    2014-08-30

    This document analyzes the optical, material, and photobiological hazards of LED light sources compared to conventional light sources. It documents that LEDs generally produce the same amount of blue light, which is the primary contributor to the risks, as other sources at the same CCT. Duv may have some effect on the amount of blue light, but CRI does not.

  20. Which colors would extraterrestrial civilizations use to transmit signals?: The ;magic wavelengths; for optical SETI

    Science.gov (United States)

    Narusawa, Shin-ya; Aota, Tatusya; Kishimoto, Ryo

    2018-04-01

    In the case of radio SETI, there are predicted frequencies which extraterrestrial beings select to send messages to other civilizations. Those are called ;magic frequencies. Considering the optical region, terrestrial technologies can not transmit arbitrary wavelengths of high-power optical lasers, easily. In this article, we discuss communications among civilizations with the same level of technology as us to enhance the persuasive power. It might be possible to make a reasonable assumption about the laser wavelengths transmitted by extraterrestrial intelligences to benefit optical SETI (OSETI) methods. Therefore, we propose some ;magic wavelengths; for spectroscopic OSETI observations in this article. From the senders point of view, we argue that the most favorable wavelength used for interstellar communication would be the one of YAG lasers, at 1.064 μm or its Second Harmonic Generation (532.1 nm). On the contrary, there are basic absorption lines in the optical spectra, which are frequently observed by astrophysicists on Earth. It is possible that the extraterrestrials used lasers, which wavelengths are tuned to such absorption lines for sending messages. In that case, there is a possibility that SHG and/or Sum Frequency Generation of YAG and YLF lasers are used. We propose three lines at, 393.8 nm (near the Ca K line), 656.5 nm (near the Hα line) and 589.1 nm (Na D2 line) as the magic wavelengths.

  1. Characterization of Optical Attenuation by Colored Dissolved Organic Matter (CDOM) in the Red Sea

    KAUST Repository

    Tiwari, Surya Prakash; Kü rten, Benjamin; Jones, Burton

    2016-01-01

    from two different instruments (i.e. a spectrophotometer and WET Labs ac-s sensor), and assesses the variations in optical properties of CDOM in the Red Sea using data collected in 2014 and 2015. Three global inversion algorithms (Garver

  2. Optical efficiency enhancement in white organic light-emitting diode display with high color gamut using patterned quantum dot film and long pass filter

    Science.gov (United States)

    Kim, Hyo-Jun; Shin, Min-Ho; Kim, Young-Joo

    2016-08-01

    A new structure for white organic light-emitting diode (OLED) displays with a patterned quantum dot (QD) film and a long pass filter (LPF) was proposed and evaluated to realize both a high color gamut and high optical efficiency. Since optical efficiency is a critical parameter in white OLED displays with a high color gamut, a red or green QD film as a color-converting component and an LPF as a light-recycling component are introduced to be adjusted via the characteristics of a color filter (CF). Compared with a conventional white OLED without both a QD film and the LPF, it was confirmed experimentally that the optical powers of red and green light in a new white OLED display were increased by 54.1 and 24.7% using a 30 wt % red QD film and a 20 wt % green QD film with the LPF, respectively. In addition, the white OLED with both a QD film and the LPF resulted in an increase in the color gamut from 98 to 107% (NTSC x,y ratio) due to the narrow emission linewidth of the QDs.

  3. Bio-optical profiling floats as new observational tools for biogeochemical and ecosystem studies: Potential synergies with ocean color remote sensing

    CSIR Research Space (South Africa)

    Claustre, H

    2009-09-01

    Full Text Available Color Coordinating Group) BIO-Argo working group is to elaborate recommendations in view of a future use of bio-optical profiling floats as part of a network that would include a global array that could be "Argo-relevant", and specific arrays that would...

  4. Optical detection of two-color-fluorophore barcode for nanopore DNA sensing

    Science.gov (United States)

    Zhang, M.; Sychugov, I.; Schmidt, T.; Linnros, J.

    2015-06-01

    A simple schematic on parallel optical detection of two-fluorophore barcode for single-molecule nanopore sensing is presented. The chosen two fluorophores, ATTO-532 and DY-521-XL, emitting in well-separated spectrum range can be excited at the same wavelength. A beam splitter was employed to separate signals from the two fluorophores and guide them to the same CCD camera. Based on a conventional microscope, sources of background in the nanopore sensing system, including membranes, compounds in buffer solution, and a detection cell was characterized. By photoluminescence excitation measurements, it turned out that silicon membrane has a negligible photoluminescence under the examined excitation from 440 nm to 560 nm, in comparison with a silicon nitrite membrane. Further, background signals from the detection cell were suppressed. Brownian motion of 450 bps DNA labelled with single ATTO-532 or DY-521-XL was successfully recorded by our optical system.

  5. Observations and theoretical evaluations of color changes of traveling light beams caused by optical rotation phenomena in sugared water and their applications for educational purposes

    Science.gov (United States)

    Tokumitsu, Seika; Hasegawa, Makoto

    2017-08-01

    Investigations were conducted for the purposes of understanding coloring phenomena to be caused by optical rotation of polarized light beams in sugared water and realizing their applications as educational tools. By allowing polarized laser beams in red, blue or green to travel in sugared water of certain concentrations, changes in their intensities were measured while changing a distance between a pair of polarizing plates in the sugared water. An equation was established for a theoretical value for the angle of rotation for light of any colors (wavelengths) travelling in sugared water of any concentrations. The predicted results exhibited satisfactory matching with the measured values. In addition, the intensities of transmitted laser beams, as well as colors to be observable when a white-color LED torch was employed as a light source, were also become predictable, and the predicted results were well-matched with the observation results.

  6. High-z X-ray Obscured Quasars in Galaxies with Extreme Mid-IR/Optical Colors

    Science.gov (United States)

    Piconcelli, E.; Lanzuisi, G.; Fiore, F.; Feruglio, C.; Vignali, C.; Salvato, M.; Grappioni, C.

    2009-05-01

    Extreme Optical/Mid-IR color cuts have been used to uncover a population of dust-enshrouded, mid-IR luminous galaxies at high redshifts. Several lines of evidence point towards the presence of an heavily absorbed, possibly Compton-thick quasar at the heart of these systems. Nonetheless, the X-ray spectral properties of these intriguing sources still remain largely unexplored. Here we present an X-ray spectroscopic study of a large sample of 44 extreme dust-obscured galaxies (EDOGs) with F24 μm/FR>2000 and F24 μm>1.3 mJy selected from a 6 deg2 region in the SWIRE fields. The application of our selection criteria to a wide area survey has been capable of unveiling a population of X-ray luminous, absorbed z>1 quasars which is mostly missed in the traditional optical/X-ray surveys performed so far. Advances in the understanding of the X-ray properties of these recently-discovered sources by Simbol-X observations will be also discussed.

  7. Optical assessment of colored dissolved organic matter and its related parameters in dynamic coastal water systems

    Science.gov (United States)

    Shanmugam, Palanisamy; Varunan, Theenathayalan; Nagendra Jaiganesh, S. N.; Sahay, Arvind; Chauhan, Prakash

    2016-06-01

    Prediction of the curve of the absorption coefficient of colored dissolved organic matter (CDOM) and differentiation between marine and terrestrially derived CDOM pools in coastal environments are hampered by a high degree of variability in the composition and concentration of CDOM, uncertainties in retrieved remote sensing reflectance and the weak signal-to-noise ratio of space-borne instruments. In the present study, a hybrid model is presented along with empirical methods to remotely determine the amount and type of CDOM in coastal and inland water environments. A large set of in-situ data collected on several oceanographic cruises and field campaigns from different regional waters was used to develop empirical methods for studying the distribution and dynamics of CDOM, dissolved organic carbon (DOC) and salinity. Our validation analyses demonstrated that the hybrid model is a better descriptor of CDOM absorption spectra compared to the existing models. Additional spectral slope parameters included in the present model to differentiate between terrestrially derived and marine CDOM pools make a substantial improvement over those existing models. Empirical algorithms to derive CDOM, DOC and salinity from remote sensing reflectance data demonstrated success in retrieval of these products with significantly low mean relative percent differences from large in-situ measurements. The performance of these algorithms was further assessed using three hyperspectral HICO images acquired simultaneously with our field measurements in productive coastal and lagoon waters on the southeast part of India. The validation match-ups of CDOM and salinity showed good agreement between HICO retrievals and field observations. Further analyses of these data showed significant temporal changes in CDOM and phytoplankton absorption coefficients with a distinct phase shift between these two products. Healthy phytoplankton cells and macrophytes were recognized to directly contribute to the

  8. Investigation of radio objects with continuos optical spectra. The results of four-color electrophotometric observations

    International Nuclear Information System (INIS)

    Beskin, G.M.; Lyutyj, V.M.; Neizvestnyj, S.I.; Pustil'nik, S.I.; Shvartsman, V.F.

    1985-01-01

    The results of UBVR photometry of 30 radio objects with continuous optical spectra (ROCOSes) are reported. The observations were performed using five telescopes during the years 1979-1982; 54 values have been obtained of U, B, V magnitudes and 26 ones of R magnitude. Colours for 16 ROCOSes have been obtained for the first time. The analysis of the data results in the following conclusions. 1) Practically all colours of ROCOSes have proved to be in the region of localization of BL Lac objects' colours on UBV and BVR diagrams. This fact (altogether with the other data) indicates on the proximity of the objects of the two classes. 2) In half of all cases, instantaneous colours of ROCOSes corresponded to purely power-law optical continua F(ν) varies as νsup(α) with α approximately= -(1-2.5). 3) In the remaining cases, optical continua differed significantly from the power-law ones. 4) 6 ROCOSes appeared to be in the phases of deep minimum of brightness at the moment of observations (namely, about 3sup(m)-5sup(m) fainter than in the brightest phase known from the literature). The UBVR colours of none of them give indication on the presence of an elliptical galaxy which, according to conventional concepts, must encompass a variable nonthermal source. 5) Two blue objects, 0548+165 and 0713+199, which are situated at low galactic latitudes (b 2 =-5 deg and +14 deg respectively) have shown colours unusual for lacertids. Appendices contain the results of theoretical calculations of (U-B), (B-V) and (V-R) colours for purely power-law spectra F(ν)=constxνsup(α) with α in the range (-6.5-+2.5) and the results of UBV photometry of the BL Lac object OJ 287 during the years 1976-1982 (24 measurements)

  9. Classifying coastal resources by integrating optical and radar imagery and color infrared photography

    Science.gov (United States)

    Ramsey, Elijah W.; Nelson, Gene A.; Sapkota, Sijan

    1998-01-01

    A progressive classification of a marsh and forest system using Landsat Thematic Mapper (TM), color infrared (CIR) photograph, and ERS-1 synthetic aperture radar (SAR) data improved classification accuracy when compared to classification using solely TM reflective band data. The classification resulted in a detailed identification of differences within a nearly monotypic black needlerush marsh. Accuracy percentages of these classes were surprisingly high given the complexities of classification. The detailed classification resulted in a more accurate portrayal of the marsh transgressive sequence than was obtainable with TM data alone. Individual sensor contribution to the improved classification was compared to that using only the six reflective TM bands. Individually, the green reflective CIR and SAR data identified broad categories of water, marsh, and forest. In combination with TM, SAR and the green CIR band each improved overall accuracy by about 3% and 15% respectively. The SAR data improved the TM classification accuracy mostly in the marsh classes. The green CIR data also improved the marsh classification accuracy and accuracies in some water classes. The final combination of all sensor data improved almost all class accuracies from 2% to 70% with an overall improvement of about 20% over TM data alone. Not only was the identification of vegetation types improved, but the spatial detail of the classification approached 10 m in some areas.

  10. Doppler flowmetry in preeclampsia.

    Science.gov (United States)

    Zahumensky, J

    2009-01-01

    The purpose of this study was to summarize the new published data on the Doppler flowmetry in preeclampsia. We summarize the new published data on the Doppler flowmetry in uteroplacental, fetoplacental and fetal circulation in preeclampsia. The present review summarized the results of clinical research on the Doppler flowmetry in the screening of risk of preclampsia, in the diagnosis of preclampsia and in the fetal risk in preclampsia (Ref. 19). Full Text (Free, PDF) www.bmj.sk.

  11. Structural and Visible-Near Infrared Optical Properties of Cr-Doped TiO2 for Colored Cool Pigments

    Science.gov (United States)

    Yuan, Le; Weng, Xiaolong; Zhou, Ming; Zhang, Qingyong; Deng, Longjiang

    2017-11-01

    Chromium-doped TiO2 pigments were synthesized via a solid-state reaction method and studied with X-ray diffraction, SEM, XPS, and UV-VIS-NIR reflectance spectroscopy. The incorporation of Cr3+ accelerates the transition from the anatase phase to the rutile phase and compresses the crystal lattice. Moreover, the particle morphology, energy gap, and reflectance spectrum of Cr-doped TiO2 pigments is affected by the crystal structure and doping concentration. For the rutile samples, some of the Cr3+ ions are oxidized to Cr4+ after sintering at a high temperature, which leads to a strong near-infrared absorption band due to the 3A2 → 3 T1 electric dipole-allowed transitions of Cr4+. And the decrease of the band gap causes an obvious redshift of the optical absorption edges as the doping concentration increases. Thus, the VIS and near-infrared average reflectance of the rutile Ti1 - x Cr x O2 sample decrease by 60.2 and 58%, respectively, when the Cr content increases to x = 0.0375. Meanwhile, the color changes to black brown. However, for the anatase Ti1 - x Cr x O2 pigments, only the VIS reflection spectrum is inhibited by forming some characteristic visible light absorption peaks of Cr3+. The morphology, band gap, and NIR reflectance are not significantly affected. Finally, a Cr-doped anatase TiO2 pigment with a brownish-yellow color and 90% near-infrared reflectance can be obtained.

  12. Optical properties of Colored Dissolved Organic Matter (CDOM) on the East Siberian shelf

    Science.gov (United States)

    Semiletov, I. P.; Pugach, S.; Pipko, I.

    2015-12-01

    The Great Siberian Rivers integrate meteorological and hydrological changes in their watersheds and play a significant role in the physical and biogeochemical regime of the Arctic Ocean. Given the magnitude of Siberian Arctic dissolved organic matter (DOM) export and the uncertain extent to which it is degraded to greenhouse gases, intensified studies to better quantify and understand this large carbon pool and processes acting on it are urgently needed. The East Siberian Arctic shelf is characterized by the highest rate of coastal erosion and significant volume of the riverine discharge which derived terrigenous DOM in the Arctic Ocean. DOM plays a significant role in freshwater and marine aquatic ecosystems including its effects on nutrients and carbon cycling. The colored fraction of DOM, CDOM, directly affects the quantity and spectral quality of available light, thereby impaction both primary production and UV exposure in aquatic ecosystems. Since 2003 we measure CDOM in the East Siberian Arctic Seas (ESAS) in situ using the WETStar fluorometer which doesn't require prefiltration of sample. Combined analysis of CDOM and DOC data obtained at near-annual basis in (2003-2011) demonstrate a high degree of correlation between these parameters. For all the measured samples taken during the ISSS cruises (2003, 2004, 2005, 2008, 2011), there is an overall linear relationship between DOC concentration, CDOM, and salinity. Here we report the spatial-time variability of river-borne DOM in the ESAS using CDOM as a proxy parameter. Higher absorption coefficients (a254), spectral slope parameter over range 275-295 nm (S275-295) and CDOM concentrations reflect the dominant contribution of terrigenous DOM. It is shown that the attenuation light coefficient in the shallow ESAS is mostly determined by riverine CDOM.

  13. Optical granulometric analysis of sedimentary deposits by color segmentation-based software: OPTGRAN-CS

    Science.gov (United States)

    Chávez, G. Moreno; Sarocchi, D.; Santana, E. Arce; Borselli, L.

    2015-12-01

    The study of grain size distribution is fundamental for understanding sedimentological environments. Through these analyses, clast erosion, transport and deposition processes can be interpreted and modeled. However, grain size distribution analysis can be difficult in some outcrops due to the number and complexity of the arrangement of clasts and matrix and their physical size. Despite various technological advances, it is almost impossible to get the full grain size distribution (blocks to sand grain size) with a single method or instrument of analysis. For this reason development in this area continues to be fundamental. In recent years, various methods of particle size analysis by automatic image processing have been developed, due to their potential advantages with respect to classical ones; speed and final detailed content of information (virtually for each analyzed particle). In this framework, we have developed a novel algorithm and software for grain size distribution analysis, based on color image segmentation using an entropy-controlled quadratic Markov measure field algorithm and the Rosiwal method for counting intersections between clast and linear transects in the images. We test the novel algorithm in different sedimentary deposit types from 14 varieties of sedimentological environments. The results of the new algorithm were compared with grain counts performed manually by the same Rosiwal methods applied by experts. The new algorithm has the same accuracy as a classical manual count process, but the application of this innovative methodology is much easier and dramatically less time-consuming. The final productivity of the new software for analysis of clasts deposits after recording field outcrop images can be increased significantly.

  14. The Origins of UV-optical Color Gradients in Star-forming Galaxies at z ˜ 2: Predominant Dust Gradients but Negligible sSFR Gradients

    Science.gov (United States)

    Liu, F. S.; Jiang, Dongfei; Faber, S. M.; Koo, David C.; Yesuf, Hassen M.; Tacchella, Sandro; Mao, Shude; Wang, Weichen; Guo, Yicheng; Fang, Jerome J.; Barro, Guillermo; Zheng, Xianzhong; Jia, Meng; Tong, Wei; Liu, Lu; Meng, Xianmin

    2017-07-01

    The rest-frame UV-optical (I.e., NUV - B) color is sensitive to both low-level recent star formation (specific star formation rate—sSFR) and dust. In this Letter, we extend our previous work on the origins of NUV - B color gradients in star-forming galaxies (SFGs) at z˜ 1 to those at z˜ 2. We use a sample of 1335 large (semimajor axis radius {R}{SMA}> 0\\buildrel{\\prime\\prime}\\over{.} 18) SFGs with extended UV emission out to 2{R}{SMA} in the mass range {M}* ={10}9{--}{10}11 {M}⊙ at 1.5negative NUV - B color gradients (redder centers), and their color gradients strongly increase with galaxy mass. We also show that the global rest-frame FUV - NUV color is approximately linear with {A}{{V}}, which is derived by modeling the observed integrated FUV to NIR spectral energy distributions of the galaxies. Applying this integrated calibration to our spatially resolved data, we find a negative dust gradient (more dust extinguished in the centers), which steadily becomes steeper with galaxy mass. We further find that the NUV - B color gradients become nearly zero after correcting for dust gradients regardless of galaxy mass. This indicates that the sSFR gradients are negligible and dust reddening is likely the principal cause of negative UV-optical color gradients in these SFGs. Our findings support that the buildup of the stellar mass in SFGs at Cosmic Noon is self-similar inside 2{R}{SMA}.

  15. Doppler ultrasound exam of an arm or leg

    Science.gov (United States)

    Peripheral vascular disease - Doppler; PVD - Doppler; PAD - Doppler; Blockage of leg arteries - Doppler; Intermittent claudication - Doppler; Arterial insufficiency of the legs - Doppler; Leg pain and ...

  16. Dynamic studies of small animals with a four-color diffuse optical tomography imager

    International Nuclear Information System (INIS)

    Schmitz, Christoph H.; Graber, Harry L.; Pei Yaling; Farber, Mark; Stewart, Mark; Levina, Rita D.; Levin, Mikhail B.; Xu Yong; Barbour, Randall L.

    2005-01-01

    We present newly developed instrumentation for full-tomographic four-wavelength, continuous wave, diffuse optical tomography (DOT) imaging on small animals. A small-animal imaging stage was constructed, from materials compatible with in-magnet studies, which offers stereotaxic fixation of the animal and precise, stable probe positioning. Instrument performance, based on calibration and phantom studies, demonstrates excellent long-term signal stability. DOT measurements of the functional rat brain response to electric paw stimulation are presented, and these demonstrate high data quality and excellent sensitivity to hemodynamic changes. A general linear model analysis on individual trials is used to localize and quantify the occurrence of functional behavior associated with the different hemoglobin state responses. Statistical evaluation of outcomes of individual trials is employed to identify significant regional response variations for different stimulation sites. Image results reveal a diffuse cortical response and a strong reaction of the thalamus, both indicative of activation of pain pathways by the stimulation. In addition, a weaker lateralized functional component is observed in the brain response, suggesting presence of motor activation. An important outcome of the experiment is that it shows that reactions to individual provocations can be monitored, without having to resort to signal averaging. Thus the described technology may be useful for studies of long-term trends in hemodynamic response, as would occur, for example, in behavioral studies involving freely moving animals

  17. The duplex-Doppler colour echography of the scrotum and testicles in adults and boys. II. the contribution of the urgent study of acute scrotum symptoms; Ecografia duples-Doppler color del escroto y el testiculo en el adulto y el nino. II. Aportacion al estudio urgente del escroto agudo

    Energy Technology Data Exchange (ETDEWEB)

    Rangel-Villalobos, E.; Jimenez-Castellanos, R.; Bustos, C.; Linares, A.; Gonzalez-Prada, F. [Hospital Universitario Virgen Macarena. Sevilla (Spain)

    1999-07-01

    To analyse the findings, contributions and limitations of the Doppler echography for the urgent study of acute scrotum symptoms, both in adults and in boys. 60 patients (22 adults and 38 boys) with acute scrotal symptomatology were examined using B mode echography, followed by a colour duplex-Doppler (CDD) echography with a lineal 7.5 MHz transducer. We compared the findings obtained with those of the healthy contralateral testicle and with surgery or clinical-echographical evolution. The most common pathology was inflammation (27%) followed by ischemic (24%) and traumatic (17%). 12% of the patients had miscellaneous conditions. To conclude, in 20% of the cases the B mode and the Doppler examination was normal, the symptoms were resolved spontaneously. After carrying out the CDD only 14 (23%) of the cases needed immediate surgery and 3 (5%) delayed surgery, the remaining 43 (72%) patients responded to the traditional treatment. The CDD allows for a safe, quick and harmless diagnosis in practically all the acute scrotum cases, for both adults and boys. Its limitations in pre-puberty patients or in cases that were atypical are overcome when put in the hands of an expert radiologist, as they need a longer exploration time and suitable Doppler equipment. The main contribution to the urgent diagnosis of acute scrotum symptoms is that it accurately establishes which patients should be chosen for immediate surgery. (Author) 33 refs.

  18. Differential doppler heterodyning technique

    DEFF Research Database (Denmark)

    Lading, Lars

    1971-01-01

    Measuring velocity without disturbing the moving object is possible by use of the laser doppler heterodyning technique. Theoretical considerations on the doppler shift show that the antenna property of the photodetector can solve an apparent conflict between two different ways of calculating...

  19. Doppler ultrasound monitoring technology.

    Science.gov (United States)

    Docker, M F

    1993-03-01

    Developments in the signal processing of Doppler ultrasound used for the detection of fetal heart rate (FHR) have improved the operation of cardiotocographs. These developments are reviewed and the advantages and disadvantages of the various Doppler and signal processing methods are compared.

  20. The Cognitive Doppler.

    Science.gov (United States)

    Kozoil, Micah E.

    1989-01-01

    Discusses the learning needs of students in the concrete operational stage in mathematics. Identifies the phenomenon of reduced cognitive performance in an out-of-class environment as the "Cognitive Doppler." Suggests methods of reducing the pronounced effects of the Cognitive Doppler by capitalizing on the students' ability to memorize…

  1. Computer-assisted quantitative assessment of power Doppler US: effects of microbubble contrast agent in the differentiation of breast tumors

    International Nuclear Information System (INIS)

    Kettenbach, Joachim; Helbich, Thomas H.; Huber, Sabine; Zuna, Ivan; Dock, Wolfgang

    2005-01-01

    Rationale and objectives: To objectively quantify the effects of a microbubble contrast agent to differentiate breast tumors with power doppler ultrasound and to compare these results with color doppler ultrasound (CD US). Methods: In 47 patients a microbubble contrast agent was injected intravenously. Computer-assisted quantitative assessment of the color pixel density was performed to evaluate the increase in Doppler signals. Results were compared to previously published results of a color Doppler ultrasound study. Results: Peak color pixel density at contrast-enhanced power Doppler ultrasound was higher for carcinomas than for benign tumors (P < 0.03). Time to peak enhancement was shorter in carcinomas than in benign tumors (P < 0.01). For both parameters, diagnostic accuracy of power Doppler ultrasound was 69 and 78%, and for color Doppler ultrasound 62 and 76%, respectively. Conclusions: Quantitative assessment of contrast-enhanced power Doppler ultrasound showed significant differences in malignant and benign breast tumors. Diagnostic accuracy of contrast-enhanced power Doppler ultrasound was higher compared to color Doppler ultrasound

  2. Grading of Age-Related Macular Degeneration: Comparison between Color Fundus Photography, Fluorescein Angiography, and Spectral Domain Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Nils F. Mokwa

    2013-01-01

    Full Text Available Purpose. To compare color fundus photography (FP, fluorescein angiography (FA, and spectral domain optical coherence tomography (SDOCT for the detection of age-related macular degeneration (AMD, choroidal neovascularisation (CNV, and CNV activity. Methods. FPs, FAs, and SDOCT volume scans from 120 eyes of 66 AMD and control patients were randomly collected. Control eyes were required to show no AMD, but other retinal pathology was allowed. The presence of drusen, pigmentary changes, CNV, and signs for CNV activity was independently analyzed for all imaging modalities. Results. AMD was diagnosed based on FP in 75 eyes. SDOCT and FA showed sensitivity (specificity of 89% (76% and 92% (82%, respectively. CNV was present on FA in 68 eyes. Sensitivity (specificity was 78% (100% for FP and 94% (98% for SDOCT. CNV activity was detected by SDOCT or FA in 60 eyes with an agreement in 46 eyes. Sensitivity was 88% for SDOCT and 88% for FA. FP showed sensitivity of 38% and specificity of 98%. Conclusions. CNV lesions and activity may be missed by FP alone, but FP may help identifying drusen and pigmentary changes. SDOCT is highly sensitive for the detection of AMD, CNV, and CNV activity; however, it cannot fully replace FA.

  3. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  4. Long-range, wide-field swept-source optical coherence tomography with GPU accelerated digital lock-in Doppler vibrography for real-time, in vivo middle ear diagnostics.

    Science.gov (United States)

    MacDougall, Dan; Farrell, Joshua; Brown, Jeremy; Bance, Manohar; Adamson, Robert

    2016-11-01

    We present the design, implementation and validation of a swept-source optical coherence tomography (OCT) system for real-time imaging of the human middle ear in live patients. Our system consists of a highly phase-stable Vernier-tuned distributed Bragg-reflector laser along with a real-time processing engine implemented on a graphics processing unit. We use the system to demonstrate, for the first time in live subjects, real-time Doppler measurements of middle ear vibration in response to sound, video rate 2D B-mode imaging of the middle ear and 3D volumetric B-mode imaging. All measurements were performed non-invasively through the intact tympanic membrane demonstrating that the technology is readily translatable to the clinic.

  5. Comparison of Color Fundus Photography, Infrared Fundus Photography, and Optical Coherence Tomography in Detecting Retinal Hamartoma in Patients with Tuberous Sclerosis Complex.

    Science.gov (United States)

    Bai, Da-Yong; Wang, Xu; Zhao, Jun-Yang; Li, Li; Gao, Jun; Wang, Ning-Li

    2016-05-20

    A sensitive method is required to detect retinal hamartomas in patients with tuberous sclerosis complex (TSC). The aim of the present study was to compare the color fundus photography, infrared imaging (IFG), and optical coherence tomography (OCT) in the detection rate of retinal hamartoma in patients with TSC. This study included 11 patients (22 eyes) with TSC, who underwent color fundus photography, IFG, and spectral-domain OCT to detect retinal hamartomas. TSC1 and TSC2RESULTS: The mean age of the 11 patients was 8.0 ± 2.1 years. The mean spherical equivalent was -0.55 ± 1.42 D by autorefraction with cycloplegia. In 11 patients (22 eyes), OCT, infrared fundus photography, and color fundus photography revealed 26, 18, and 9 hamartomas, respectively. The predominant hamartoma was type I (55.6%). All the hamartomas that detected by color fundus photography or IFG can be detected by OCT. Among the methods of color fundus photography, IFG, and OCT, the OCT has higher detection rate for retinal hamartoma in TSC patients; therefore, OCT might be promising for the clinical diagnosis of TSC.

  6. Doppler radar flowmeter

    Science.gov (United States)

    Petlevich, Walter J.; Sverdrup, Edward F.

    1978-01-01

    A Doppler radar flowmeter comprises a transceiver which produces an audio frequency output related to the Doppler shift in frequency between radio waves backscattered from particulate matter carried in a fluid and the radiated radio waves. A variable gain amplifier and low pass filter are provided for amplifying and filtering the transceiver output. A frequency counter having a variable triggering level is also provided to determine the magnitude of the Doppler shift. A calibration method is disclosed wherein the amplifier gain and frequency counter trigger level are adjusted to achieve plateaus in the output of the frequency counter and thereby allow calibration without the necessity of being able to visually observe the flow.

  7. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... anatomy. The most common use of the technique is to image the movement of blood through the heart, arteries and veins, but it may also be used to image the motion of solid tissues such as the heart walls. Colour Doppler imaging is now provided on almost all commercial ultrasound machines, and has been...

  8. Bio-optical profiling floats as new observational tools for biogeochemical and ecosystem studies: Potential synergies with ocean color remote sensing

    Energy Technology Data Exchange (ETDEWEB)

    Claustre, H.; Bishop, J.; Boss, E.; Bernard, S.; Berthon, J.-F.; Coatanoan, C.; Johnson, K.; Lotiker, A.; Ulloa, O.; Perry, M.J.; D' Ortenzio, F.; D' andon, O.H.F.; Uitz, J.

    2009-10-01

    Profiling floats now represent a mature technology. In parallel with their emergence, the field of miniature, low power bio-optical and biogeochemical sensors is rapidly evolving. Over recent years, the bio-geochemical and bio-optical community has begun to benefit from the increase in observational capacities by developing profiling floats that allow the measurement of key biooptical variables and subsequent products of biogeochemical and ecosystem relevance like Chlorophyll a (Chla), optical backscattering or attenuation coefficients which are proxies of Particulate Organic Carbon (POC), Colored Dissolved Organic Matter (CDOM). Thanks to recent algorithmic improvements, new bio-optical variables such as backscattering coefficient or absorption by CDOM, at present can also be extracted from space observations of ocean color. In the future, an intensification of in situ measurements by bio-optical profiling floats would permit the elaboration of unique 3D/4D bio-optical climatologies, linking surface (remotely detected) properties to their vertical distribution (measured by autonomous platforms), with which key questions in the role of the ocean in climate could be addressed. In this context, the objective of the IOCCG (International Ocean Color Coordinating Group) BIO-Argo working group is to elaborate recommendations in view of a future use of bio-optical profiling floats as part of a network that would include a global array that could be 'Argo-relevant', and specific arrays that would have more focused objectives or regional targets. The overall network, realizing true multi-scale sustained observations of global marine biogeochemistry and biooptics, should satisfy the requirements for validation of ocean color remote sensing as well as the needs of a wider community investigating the impact of global change on biogeochemical cycles and ecosystems. Regarding the global profiling float array, the recommendation is that Chla as well as POC should be the

  9. Empirical ocean color algorithms and bio-optical properties of the western coastal waters of Svalbard, Arctic

    Science.gov (United States)

    Son, Young-Sun; Kim, Hyun-cheol

    2018-05-01

    Chlorophyll (Chl) concentration is one of the key indicators identifying changes in the Arctic marine ecosystem. However, current Chl algorithms are not accurate in the Arctic Ocean due to different bio-optical properties from those in the lower latitude oceans. In this study, we evaluated the current Chl algorithms and analyzed the cause of the error in the western coastal waters of Svalbard, which are known to be sensitive to climate change. The NASA standard algorithms showed to overestimate the Chl concentration in the region. This was due to the high non-algal particles (NAP) absorption and colored dissolved organic matter (CDOM) variability at the blue wavelength. In addition, at lower Chl concentrations (0.1-0.3 mg m-3), chlorophyll-specific absorption coefficients were ∼2.3 times higher than those of other Arctic oceans. This was another reason for the overestimation of Chl concentration. OC4 algorithm-based regionally tuned-Svalbard Chl (SC4) algorithm for retrieving more accurate Chl estimates reduced the mean absolute percentage difference (APD) error from 215% to 49%, the mean relative percentage difference (RPD) error from 212% to 16%, and the normalized root mean square (RMS) error from 211% to 68%. This region has abundant suspended matter due to the melting of tidal glaciers. We evaluated the performance of total suspended matter (TSM) algorithms. Previous published TSM algorithms generally overestimated the TSM concentration in this region. The Svalbard TSM-single band algorithm for low TSM range (ST-SB-L) decreased the APD and RPD errors by 52% and 14%, respectively, but the RMS error still remained high (105%).

  10. Wide Angle Michelson Doppler Imaging Interferometer (WAMDII)

    Science.gov (United States)

    Roberts, B.

    1986-01-01

    The wide angle Michelson Doppler imaging interferometer (WAMDII) is a specialized type of optical Michelson interferometer working at sufficiently long path difference to measure Doppler shifts and to infer Doppler line widths of naturally occurring upper atmospheric Gaussian line emissions. The instrument is intended to measure vertical profiles of atmospheric winds and temperatures within the altitude range of 85 km to 300 km. The WAMDII consists of a Michelson interferometer followed by a camera lens and an 85 x 106 charge coupled device photodiode array. Narrow band filters in a filter wheel are used to isolate individual line emissions and the lens forms an image of the emitting region on the charge coupled device array.

  11. A REST-FRAME OPTICAL VIEW ON z ∼ 4 GALAXIES. I. COLOR AND AGE DISTRIBUTIONS FROM DEEP IRAC PHOTOMETRY OF THE IUDF10 AND GOODS SURVEYS

    International Nuclear Information System (INIS)

    Oesch, P. A.; Illingworth, G. D.; Gonzalez, V.; Holden, B. P.; Magee, D.; Labbé, I.; Bouwens, R. J.; Franx, M.; Trenti, M.; Van Dokkum, P. G.

    2013-01-01

    We present a study of rest-frame UV-to-optical color distributions for z ∼ 4 galaxies based on the combination of deep HST/ACS+WFC3/IR data with Spitzer/IRAC imaging. In particular, we use new, ultra-deep data from the IRAC Ultradeep Field program (IUDF10), together with previous, public IRAC data over the GOODS fields. Our sample contains a total of ∼2600 galaxies selected as B-dropout Lyman-break Galaxies in the HUDF and its deep parallel field HUDF09-2, as well as GOODS-North/South. This sample is used to investigate the UV continuum slopes β and Balmer break colors (J 125 – [4.5]) as a function of rest-frame optical luminosity (using [4.5] to avoid optical emission lines). We find that galaxies at M z * z∼4 ) are significantly redder than their lower luminosity counterparts. The UV continuum slopes and the J 125 – [4.5] colors are well correlated, indicating that the dust reddening at these redshifts is better described by an SMC-like extinction curve, rather than the typically assumed Calzetti reddening. After dust correction, we find that the galaxy population shows mean stellar population ages in the range 10 8.5 to 10 9 yr, with a dispersion of ∼0.5 dex, and only weak trends as a function of luminosity. Only a small fraction of galaxies shows Balmer break colors consistent with extremely young ages, younger than 100 Myr. Under the assumption of smooth star-formation histories, this fraction is 12%-19% for galaxies at M z 4 with only a small fraction of stars being formed in short, intense bursts of star-formation

  12. Ultrasound and Doppler examination capabilities in adult portal hypertension type definition

    Directory of Open Access Journals (Sweden)

    N. V. Tumanskaya

    2015-08-01

    Full Text Available Early portal hypertension type diagnostics is an ultimate factor concerning kind and tactics of treatment. Aim. To objectify ultrasound examination capabilities, portal hemodynamics were studied in 97 patients using impulse and color doppler. Methods and results. It was ascertained that impulse and color doppler examination allows to visualize portal vein and its branches’ structural abnormalities, define subhepatic and intrahepatic types of portal hypertension, find thrombosis and characterize its stages. In cirrhosis patients with portal hypertension, homogenous doppler signal was received from the portal vessels lumen, while signs of intraluminar pathology were seen in the case of thrombosis of portal vein. Conclusion. This means that ultrasound examination of portal vein and its branches with impulse and color doppler is informative, non invasive method, which helps to define stages of portal hypertension. Doppler ultrasonography doesn’t have negative effect of ionizing radiation and can be used for the repeated research in the dynamics of disease.

  13. Bio-Optical Properties of the Inner Continental Shelf off Santos Estuarine System, Southeastern Brazil, and their Implications for Ocean Color Algorithm Performance

    Directory of Open Access Journals (Sweden)

    Melissa Carvalho

    2014-07-01

    Full Text Available Optical characterizations of coastal water masses are important tools for a better understanding of physical and biochemical processes and aid the optimization of ocean color algorithms. In this study we present three optical classes of water observed during October/2005 and March/2006 on the inner continental shelf adjacent to Santos Bay (Brazil, based on remote sensing reflectance. ANOVA indicated a crescent estuarine influence in classes 1 to 3. Class 3 presented the highest chlorophyll-a and nutrient concentration and highest light absorption coefficients. Colored dissolved organic matter (CDOM dominated the light absorption in all classes and was strongly correlated to salinity in October/2005 due to the influence of the La Plata plume. The results indicated that CDOM dynamics in the Santos inner shelf are very complex. The performance of global chlorophyll algorithms was significantly smaller for October/2005 than for March/2006. As inconsistent changes in light absorption spectra by phytoplankton were detected between samplings, the results show that future bio-optical algorithms for this region must be optimized preferentially considering CDOM optical parameters.

  14. Scanning Color Laser Microscope

    Science.gov (United States)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1988-01-01

    A confocal color laser microscope which utilizes a three color laser light source (Red: He-Ne, Green: Ar, Blue: Ar) has been developed and is finding useful applications in the semiconductor field. The color laser microscope, when compared to a conventional microscope, offers superior color separation, higher resolution, and sharper contrast. Recently some new functions including a Focus Scan Memory, a Surface Profile Measurement System, a Critical Dimension Measurement system (CD) and an Optical Beam Induced Current Function (OBIC) have been developed for the color laser microscope. This paper will discuss these new features.

  15. Avaliação dos tumores hepáticos ao Doppler Doppler evaluation of liver tumors

    Directory of Open Access Journals (Sweden)

    Márcio Martins Machado

    2004-10-01

    Full Text Available Os avanços recentes na ultra-sonografia têm ampliado a possibilidade de detecção de tumores hepáticos. Isto tem auxiliado na perspectiva de melhora do prognóstico destes pacientes, à medida que novas técnicas terapêuticas têm surgido. Neste artigo os autores relatam achados ao Doppler que podem auxiliar na identificação e caracterização dos tumores hepáticos, avaliando dados do Doppler colorido, pulsado e do Doppler de amplitude ("power Doppler". Fazem, também, referência a novas modalidades de imagem, como o uso da harmônica.Recent advances in ultrasound have optimized the detection of liver tumors and helped to improve the prognosis of patients with this condition as newly developed and improved therapeutic modalities have been established. The authors review important Doppler findings which may help in the identification and characterization of some hepatic tumors through the evaluation of color Doppler, pulsed Doppler and power Doppler features. New imaging methods such as the use of harmonics imaging are also reviewed.

  16. Color transparency

    International Nuclear Information System (INIS)

    Miller, G.A.

    1993-01-01

    Imagine shooting a beam of protons of high momentum P through an atomic nucleus. Usually the nuclear interactions prevent the particles from emerging with momentum ∼P. Further, the angular distribution of elastically scattered protons is close to the optical diffraction pattern produced by a black disk. Thus the nucleus acts as a black disk and is not transparent. However, certain high momentum transfer reactions in which a proton is knocked out of the nucleus may be completely different. Suppose that the high momentum transfer process leads to the formation of a small-size color singlet wavepacket that is ejected from the nucleus. The effects of gluons emitted by color singlet systems of closely separated quarks and gluons tend to cancel. Thus the wavepacket-nuclear interactions are suppressed, the nucleus becomes transparant and one says that color transparency CT occurs. The observation of CT also requires that the wavepacket not expand very much while it moves through the nucleus. Simple quantum mechanical formulations can assess this expansion. The creation of a small-sized wavepacket is expected in asymptotic perturbative effects. The author reviews the few experimental attempts to observe color transparency in nuclear (e,e'p) and (p,pp) reactions and interpret the data and their implications

  17. SPIDER. IV. OPTICAL AND NEAR-INFRARED COLOR GRADIENTS IN EARLY-TYPE GALAXIES: NEW INSIGHT INTO CORRELATIONS WITH GALAXY PROPERTIES

    International Nuclear Information System (INIS)

    La Barbera, F.; De Carvalho, R. R.; De La Rosa, I. G.; Gal, R. R.; Swindle, R.; Lopes, P. A. A.

    2010-01-01

    We present an analysis of stellar population gradients in 4546 early-type galaxies (ETGs) with photometry in grizYHJK along with optical spectroscopy. ETGs were selected as bulge-dominated systems, displaying passive spectra within the SDSS fibers. A new approach is described which utilizes color information to constrain age and metallicity gradients. Defining an effective color gradient, ∇ * , which incorporates all of the available color indices, we investigate how ∇ * varies with galaxy mass proxies, i.e., velocity dispersion, stellar (M * ) and dynamical (M dyn ) masses, as well as age, metallicity, and [α/Fe]. ETGs with M dyn larger than 8.5 x 10 10 M sun have increasing age gradients and decreasing metallicity gradients with respect to mass, metallicity, and enhancement. We find that velocity dispersion and [α/Fe] are the main drivers of these correlations. ETGs with 2.5 x 10 10 M sun ≤ M dyn ≤ 8.5 x 10 10 M sun show no correlation of age, metallicity, and color gradients with respect to mass, although color gradients still correlate with stellar population parameters, and these correlations are independent of each other. In both mass regimes, the striking anti-correlation between color gradient and α-enhancement is significant at ∼5σ and results from the fact that metallicity gradient decreases with [α/Fe]. This anti-correlation may reflect the fact that star formation and metallicity enrichment are regulated by the interplay between the energy input from supernovae, and the temperature and pressure of the hot X-ray gas in ETGs. For all mass ranges, positive age gradients are associated with old galaxies (>5-7 Gyr). For galaxies younger than ∼5 Gyr, mostly at low mass, the age gradient tends to be anti-correlated with the Age parameter, with more positive gradients at younger ages.

  18. Development of the doppler electron velocimeter: theory.

    Energy Technology Data Exchange (ETDEWEB)

    Reu, Phillip L.

    2007-03-01

    Measurement of dynamic events at the nano-scale is currently impossible. This paper presents the theoretical underpinnings of a method for making these measurements using electron microscopes. Building on the work of Moellenstedt and Lichte who demonstrated Doppler shifting of an electron beam with a moving electron mirror, further work is proposed to perfect and utilize this concept in dynamic measurements. Specifically, using the concept of ''fringe-counting'' with the current principles of transmission electron holography, an extension of these methods to dynamic measurements is proposed. A presentation of the theory of Doppler electron wave shifting is given, starting from the development of the de Broglie wave, up through the equations describing interference effects and Doppler shifting in electron waves. A mathematical demonstration that Doppler shifting is identical to the conceptually easier to understand idea of counting moving fringes is given by analogy to optical interferometry. Finally, potential developmental experiments and uses of a Doppler electron microscope are discussed.

  19. Role of Doppler US and MRI in diagnosis of placenta accreta

    Directory of Open Access Journals (Sweden)

    Manal Hamisa

    2015-09-01

    Conclusion: In conclusion, data of the present study show that the use of transabdominal color Doppler ultrasonography complemented by MRI in suspected cases improves the diagnostic accuracy in prediction of placenta accreta in patients with previous cesarean delivery.

  20. Value of transvaginal color Doppler ultrasound in the diagnosis and treatment of cesarean scar pregnancy%经阴道彩色多普勒超声在剖宫产术后子宫瘢痕妊娠诊治中的价值

    Institute of Scientific and Technical Information of China (English)

    杨仁东; 袁秀英; 古雯洁; 刘小媚; 钟智波; 孙晓岩

    2015-01-01

    Objective To investigate the clinical value of transvaginal color Doppler ultrasound in the diagnosis and treatment of cesarean scar pregnancy (CSP). Methods Sonographic characteristics of 21 patients with CSP in the Third People's Hospital of Dongguan City from January 2009 to October 2014 were analyzed retrospectively, 21 cases were examined by transvaginal color Doppler ultrasound, and treated with puncture and injection of medicine under vaginal ultrasonography detection, transvaginal ultrasound manifestations of 21 cases were summarized, the lesion length to di-ameter, wide diameter, anterior uterine wall peripheral arterial resistance thickness and lesions with muscular segment index (resistive index, RI) before and after drug injection for the treatment of puncture were compared. Results 21 cas-es with CSP were divided into the following types pure gestational sac type (18 cases), and complete gestational sac were showed in anterior wall of the lower part of the incision of uterus intramural under ultrasond, yolk sac, embryo bud and original fetal heart beat were seen in gestational sac of 11 cases, yolk sac, embryo bud were seen in gestation-al sac of 3 cases, but no fetal heart beat, yolk sac were only seen in gestational sac of 2 cases but no embryo bud or fetal heart beat, gestational sac shrinkage, deformation were in 2 cases, and 3 cases were the mass type, and mixed e-chogenic mass were showed in the incision of the anterior wall of hypomere of the uterus, and uterine muscular layer boundary was not clear, the incision area muscle layer was humble, ditissimus blood flow signals were showed around the gestational sac or clumps under color Doppler ultrasond, nourishing vessels were from the incision of uterine mus-cular layer, blood flow signals were seen in the mass lesions of 3 cases, spectral Doppler showed a low speed and low resistance, the RI value was 0.32-0.56. Compared with before treatment, the length and width of CSP lesions in 21 pa

  1. Steerable Doppler transducer probes

    International Nuclear Information System (INIS)

    Fidel, H.F.; Greenwood, D.L.

    1986-01-01

    An ultrasonic diagnostic probe is described which is capable of performing ultrasonic imaging and Doppler measurement consisting of: a hollow case having an acoustic window which passes ultrasonic energy and including chamber means for containing fluid located within the hollow case and adjacent to a portion of the acoustic window; imaging transducer means, located in the hollow case and outside the fluid chamber means, and oriented to direct ultrasonic energy through the acoustic window toward an area which is to be imaged; Doppler transducer means, located in the hollow case within the fluid chamber means, and movably oriented to direct Doppler signals through the acoustic window toward the imaged area; means located within the fluid chamber means and externally controlled for controllably moving the Doppler transducer means to select one of a plurality of axes in the imaged area along which the Doppler signals are to be directed; and means, located external to the fluid chamber means and responsive to the means for moving, for providing an indication signal for identifying the selected axis

  2. Glare Spot Phase Doppler Anemometry

    Science.gov (United States)

    Hespel, Camille; Ren, Kuanfang; Gréhan, Gérard; Onofri, Fabrice

    2007-06-01

    The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index would be also interesting since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemometry which uses two large beams. In this case, the images of the particle formed by the reflected and refracted light, known as glare spots, are separated in space. When a particle passes in the probe volume, the two parts in a signal obtained by a detector in forward direction are then separated in time. If two detectors are used the phase differences between two signals, the distance and the intensity ratio of reflected and refracted parts can be obtained and they provide rich information about the particle diameter and its refractive index, as well as its velocity. This paper is devoted to the numerical study of such a configuration with two theoretical models: geometrical optics and rigorous electromagnetism solution.

  3. Características cinefluoroscópicas de ocho modelos de prótesis mecánicas bivalvas implantadas en la República Argentina: su valor complementario al ecocardiograma Doppler color

    Directory of Open Access Journals (Sweden)

    Tomás F. Cianciulli

    2008-01-01

    Full Text Available Los diferentes modelos de prótesis valvulares mecánicas son numerosos y su reconocimiento por ecocardiografía es difícil. La cinefluoroscopia (CF puede complementar su identificación y su evaluación.Objetivos1 Describir las características cinefluoroscópicas de cada prótesis para su identificación. 2 Evaluar su función mediante la comparación de los gradientes del eco-Doppler con el ángulo de apertura de los discos basculantes en la CF. 3 Reconocer la capacidad de la CF para diferenciar prótesis normales de prótesis disfuncionantes.Material y métodosSe evaluaron prospectivamente 219 prótesis implantadas en 191 pacientes. Se excluyeron 14 prótesis debido a la coexistencia de disfunción sistólica ventricular izquierda grave. El análisis se realizó sobre 205 prótesis (142 aórticas y 63 mitrales.ResultadosA través de las características del anillo y de los discos, mediante la CF se logró identificar el modelo de la prótesis en el 100% de las válvulas. La movilidad de los discos permitió diferenciar prótesis normales de disfuncionantes (ángulo de apertura 79,3° ± 5,4° versus 58,7° ± 15°, respectivamente. En la CF no se pudieron perfilar los discos y/o el anillo en el 3,9% de las prótesis aórticas y en el 19,2% de las mitrales.De las 142 prótesis aórticas, el eco-Doppler identificó 112 normales y 30 disfuncionantes y de las 63 prótesis mitrales identificó 52 normales y 11 disfuncionantes.Al correlacionar ambos métodos, la sensibilidad, la especificidad, el valor predictivo positivo y el valor predictivo negativo de la fluoroscopia para diferenciar prótesis normales de disfuncionantes fueron del 71%, 93%, 67% y 94%, respectivamente.Conclusiones1 Cada modelo de prótesis valvular tiene características cinefluoroscópicas que permiten su identificación. 2 La cinefluoroscopia evalúa el funcionamiento de las prótesis mecánicas y distingue una normal de una disfuncionante. 3 Cuando hay gradientes altos y

  4. Colorism/Neo-Colorism

    Science.gov (United States)

    Snell, Joel

    2017-01-01

    There are numerous aspects to being non-Caucasian that may not be known by Whites. Persons of color suggest folks who are African, South Americans, Native Americans, Biracial, Asians and others. The question is what do these individuals feel relative to their color and facial characteristics. Eugene Robinson suggest that the future favorable color…

  5. Accurately Measuring the Color of the Ocean on Earth and from Space: Uncertainties Revisited and A Report from the Community-Led Spectral Absorption Workshop to Update and Revise the NASA Inherent Optical Properties Protocol

    Science.gov (United States)

    Neeley, Aimee Renee

    2014-01-01

    The color of the ocean (apparent optical properties or AOPs) is determined by the spectral scattering and absorption of light by its dissolved and particulate constituents.The absorption and scattering properties of the water column are the so-called inherent optical properties.

  6. Doppler ultrasound imaging techniques for assessment of synovial inflammation

    Directory of Open Access Journals (Sweden)

    Filippucci E

    2013-09-01

    Full Text Available Emilio Filippucci,1 Fausto Salaffi,1 Marina Carotti,2 Walter Grassi1 1Rheumatology Department, Polytechnic University of the Marche, Ancona, Italy; 2Department of Radiology, Polytechnic University of the Marche, Ancona, Italy Abstract: Ultrasound is an evolving technique, and the rapid progress made in ultrasound technology over the past ten years has dramatically increased its range of applications in rheumatology. One of the most exciting advances is the use of Doppler ultrasound imaging in the assessment of blood flow abnormalities at the synovial tissue level in patients with chronic inflammatory arthritis. This review describes the Doppler techniques available and their main applications in patients with inflammatory arthritis, discusses the evidence supporting their use, and outlines the latest advances in hardware and software. Spectral, color, and power Doppler allow sensitive assessment of vascular abnormalities at the synovial tissue level. Use of contrast agents enhances visualization of the small synovial vessels using color or power Doppler ultrasound and allows for accurate characterization of the rheumatoid pannus. Doppler techniques represent a unique method for assessment of synovial inflammation, showing blood flow characteristics in real time. They are safe, noninvasive, cost-effective, and have high sensitivity in revealing and monitoring synovitis. However, several questions still need to be answered. In the near future, the Doppler techniques described here, together with upcoming hardware and software facilities, will be investigated further and a consensus will be reached on their feasibility and appropriate use in daily rheumatologic practice. Keywords: power and color Doppler techniques, ultrasound, contrast media, synovitis, rheumatoid arthritis

  7. Use of Doppler ultrasound for non-invasive urodynamic diagnosis

    Directory of Open Access Journals (Sweden)

    Hideo Ozawa

    2009-01-01

    Full Text Available Objectives: A totally non-invasive transperineal urodynamic technique using Doppler ultrasonography has been developed. Methods: Since normal urine does not have blood cells, urine was thought not to produce the Doppler effects. However, basic studies confirmed that the decrease of pressure at high velocity (Bernouilli effect caused dissolved gas to form microbubbles, which are detected by Doppler ultrasonography. Subjects sat and the probe was advanced via remote control to achieve gentle contact with the perineal skin. The digital uroflow data signals and the color Doppler ultrasound video images were processed on a personal computer. The flow-velocity curves from two sites; the distal prostatic urethra just above the external sphincter (V1 and the sphincteric urethra (V2 were plotted against time. The parameters of both the pressure-flow studies and the Doppler ultrasound urodynamic studies were compared in men who had various degrees of obstruction. Results: Functional cross-sectional area at prostatic urethra (A1, calculated by Q max /V1, was lower in the group of bladder outlet obstruction (BOO vs. control group. Velocity ratio (VR, which was calculated by V1/V2, was the parameter having the best correlation with BOO index, though A1 had a similar correlation. This method is viable to diagnose the degree of BOO. Conclusions: The development of non-invasive Doppler ultrasound videourodynamics (Doppler UDS will dramatically expand the information on voiding function.

  8. The phenomenon of Doppler

    International Nuclear Information System (INIS)

    Stoll, I.; Seidlerova, I.; Schwippel, J.; Poss, O.; Solc, M.

    1992-01-01

    The book is devoted to the life and work of Christian Doppler and particularly to his links to Prague and to the Slovak town of Banska Stiavnica. Many historical facts concerning Doppler's activities as well as the history of physics and astronomy are collected. Information is also presented about the Czech Technical University, the Society of Czechoslovak Mathematicians and Physicists, the Czechoslovak Astronomical Society, the Czechoslovak Spectroscopic Society and the Czechoslovak Society for the History of Science and Technology. The publication is amply supplemented with historical pictorial material (M.D.). 92 figs., 82 refs

  9. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  10. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  11. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  12. Nonlinear optical response of a gold surface in the visible range: A study by two-color sum-frequency generation spectroscopy. I. Experimental determination.

    Science.gov (United States)

    Dalstein, L; Revel, A; Humbert, C; Busson, B

    2018-04-07

    We experimentally determine the effective nonlinear second-order susceptibility of gold over the visible spectral range. To reach that goal, we probe by vibrational two-color sum-frequency generation spectroscopy the methyl stretching region of a dodecanethiol self-assembled monolayer adsorbed on a gold film. The sum-frequency generation spectra show a remarkable shape reversal when the visible probe wavelength is tuned from 435 to 705 nm. After correcting from Fresnel effects, the methyl stretching vibrations serve as an internal reference, allowing to extract the dispersion of the absolute phase and relative amplitude of the effective nonlinear optical response of gold in the visible range.

  13. Sub-Doppler laser cooling of potassium atoms

    Energy Technology Data Exchange (ETDEWEB)

    Landini, M. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); INFN, Sezione di Firenze, I-50019 Sesto Fiorentino (Italy); Dipartimento di fisica, Universita di Trento, I-38123 Povo (Trento) (Italy); Roy, S.; Carcagni, L.; Trypogeorgos, D. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); Fattori, M.; Inguscio, M.; Modugno, G. [LENS and Dipartimento di Fisica e Astronomia, Universita di Firenze, I-50019 Sesto Fiorentino (Italy); INFN, Sezione di Firenze, I-50019 Sesto Fiorentino (Italy)

    2011-10-15

    We investigate the sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead that the combination of a dark optical molasses scheme that naturally arises in this kind of system and an adiabatic ramping of the laser parameters allows us to reach sub-Doppler temperatures for small laser detunings. We demonstrate temperatures as low as 25{+-}3 {mu}K and 47{+-}5 {mu}K in high-density samples of the two isotopes {sup 39}K and {sup 41}K, respectively. Our findings should find application to other atomic systems.

  14. Sub-Doppler laser cooling of potassium atoms

    International Nuclear Information System (INIS)

    Landini, M.; Roy, S.; Carcagni, L.; Trypogeorgos, D.; Fattori, M.; Inguscio, M.; Modugno, G.

    2011-01-01

    We investigate the sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead that the combination of a dark optical molasses scheme that naturally arises in this kind of system and an adiabatic ramping of the laser parameters allows us to reach sub-Doppler temperatures for small laser detunings. We demonstrate temperatures as low as 25±3 μK and 47±5 μK in high-density samples of the two isotopes 39 K and 41 K, respectively. Our findings should find application to other atomic systems.

  15. COLORS AND COLOR GRADIENTS IN BULGES OF GALAXIES

    NARCIS (Netherlands)

    BALCELLS, M; PELETIER, RF

    We have obtained surface photometry in U, B, R, and I for a complete optically selected sample of 45 early-type spiral galaxies, to investigate the colors and color gradients of spiral bulges. Color profiles in U-R, B-R, U-B, and R-I have been determined in wedges opening on the semiminor axes.

  16. Doppler evaluation of valvular stenosis

    International Nuclear Information System (INIS)

    Kisslo, J.; Krafchek, J.; Adams, D.; Mark, D.B.

    1986-01-01

    One of the reasons why use of Doppler echocardiography is growing rapidly is because of its utility in detecting the presence of valvular stenosis and in estimating its severity. Detection of the presence of stenotic valvular heart disease using Doppler echocardiography was originally described over 10 years ago. It has been demonstrated that Doppler blood velocity data could be used to estimate the severity of a stenotic lesion. This chapter discusses the evaluation of valvular stenois using Doppler

  17. Doppler-musical instrument

    International Nuclear Information System (INIS)

    Sato, T.J.; Watanabe, N.

    2001-01-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 μeV, even when the ultra-high energy resolution of ΔE∼0.03 μeV is attained. (author)

  18. Scanning laser Doppler vibrometry

    DEFF Research Database (Denmark)

    Brøns, Marie; Thomsen, Jon Juel

    With a Scanning Laser Doppler Vibrometer (SLDV) a vibrating surface is automatically scanned over predefined grid points, and data processed for displaying vibration properties like mode shapes, natural frequencies, damping ratios, and operational deflection shapes. Our SLDV – a PSV-500H from...

  19. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji Young [Dept. of Radiology, Ewha Womans University School of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  20. Doppler ultrasonography of the lower extremity arteries: anatomy and scanning guidelines

    Directory of Open Access Journals (Sweden)

    Ji Young Hwang

    2017-04-01

    Full Text Available Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

  1. Astronomy with the Color Blind

    Science.gov (United States)

    Smith, Donald A.; Melrose, Justyn

    2014-01-01

    The standard method to create dramatic color images in astrophotography is to record multiple black and white images, each with a different color filter in the optical path, and then tint each frame with a color appropriate to the corresponding filter. When combined, the resulting image conveys information about the sources of emission in the…

  2. Color homogeneity in LED spotlights

    NARCIS (Netherlands)

    Prins, C.R.

    2013-01-01

    Color variation in the light output of white LEDs is a common problem in LED lighting. We aim to design LED spotlights with a uniform color output while keeping the cost of the system low and the energy efficiency high. Therefore we design a special optic to eliminate the color variation of the LED.

  3. A REST-FRAME OPTICAL VIEW ON z {approx} 4 GALAXIES. I. COLOR AND AGE DISTRIBUTIONS FROM DEEP IRAC PHOTOMETRY OF THE IUDF10 AND GOODS SURVEYS

    Energy Technology Data Exchange (ETDEWEB)

    Oesch, P. A.; Illingworth, G. D.; Gonzalez, V.; Holden, B. P.; Magee, D. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Labbe, I.; Bouwens, R. J.; Franx, M. [Leiden Observatory, Leiden University, NL-2300 RA Leiden (Netherlands); Trenti, M. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Van Dokkum, P. G., E-mail: poesch@ucolick.org [Department of Astronomy, Yale University, New Haven, CT 06520 (United States)

    2013-08-01

    We present a study of rest-frame UV-to-optical color distributions for z {approx} 4 galaxies based on the combination of deep HST/ACS+WFC3/IR data with Spitzer/IRAC imaging. In particular, we use new, ultra-deep data from the IRAC Ultradeep Field program (IUDF10), together with previous, public IRAC data over the GOODS fields. Our sample contains a total of {approx}2600 galaxies selected as B-dropout Lyman-break Galaxies in the HUDF and its deep parallel field HUDF09-2, as well as GOODS-North/South. This sample is used to investigate the UV continuum slopes {beta} and Balmer break colors (J{sub 125} - [4.5]) as a function of rest-frame optical luminosity (using [4.5] to avoid optical emission lines). We find that galaxies at M{sub z} < -21.5 (roughly corresponding to L{sup *}{sub z{approx}4}) are significantly redder than their lower luminosity counterparts. The UV continuum slopes and the J{sub 125} - [4.5] colors are well correlated, indicating that the dust reddening at these redshifts is better described by an SMC-like extinction curve, rather than the typically assumed Calzetti reddening. After dust correction, we find that the galaxy population shows mean stellar population ages in the range 10{sup 8.5} to 10{sup 9} yr, with a dispersion of {approx}0.5 dex, and only weak trends as a function of luminosity. Only a small fraction of galaxies shows Balmer break colors consistent with extremely young ages, younger than 100 Myr. Under the assumption of smooth star-formation histories, this fraction is 12%-19% for galaxies at M{sub z} < -19.75. Our results are consistent with a gradual build-up of stars and dust in galaxies at z > 4 with only a small fraction of stars being formed in short, intense bursts of star-formation.

  4. An optical device capable of providing a structural color, and a corresponding method of manufacturing such a device

    DEFF Research Database (Denmark)

    2014-01-01

    ) with respect to the average surface positions. The position, size, and randomness of the protrusions are arranged so as to provide, at least up to a maximum angle of incidence (A_in) with respect to a normal to the surface, an angle-independent substantially homogeneous structural color perception for a normal...

  5. One-step Maskless Fabrication and Optical Characterization of Silicon Surfaces with Antireflective Properties and a White Color Appearance

    DEFF Research Database (Denmark)

    Sun, Ling; Feidenhans'l, Nikolaj Agentoft; Telecka, Agnieszka

    2016-01-01

    We report a simple one-step maskless fabrication of inverted pyramids on silicon wafers by reactive ion etching. The fabricated surface structures exhibit excellent anti-reflective properties: The total reflectance of the nano inverted pyramids fabricated by our method can be as low as 12% withou...... milky white color....

  6. Simple approach to three-color two-photon microscopy by a fiber-optic wavelength convertor.

    Science.gov (United States)

    Li, Kuen-Che; Huang, Lynn L H; Liang, Jhih-Hao; Chan, Ming-Che

    2016-11-01

    A simple approach to multi-color two-photon microscopy of the red, green, and blue fluorescent indicators was reported based on an ultra-compact 1.03-μm femtosecond laser and a nonlinear fiber. Inside the nonlinear fiber, the 1.03-μm laser pulses were simultaneously blue-shifted to 0.6~0.8 μm and red-shifted to 1.2~1.4 μm region by the Cherenkov radiation and fiber Raman gain effects. The wavelength-shifted 0.6~0.8 μm and 1.2~1.4 μm radiations were co-propagated with the residual non-converted 1.03-μm pulses inside the same nonlinear fiber to form a fiber-output three-color femtosecond source. The application of the multi-wavelength sources on multi-color two-photon fluorescence microscopy were also demonstrated. Overall, due to simple system configuration, convenient wavelength conversion, easy wavelength tunability within the entire 0.7~1.35 μm bio-penetration window and less requirement for high power and bulky light sources, the simple approach to multi-color two-photon microscopy could be widely applicable as an easily implemented and excellent research tool for future biomedical and possibly even clinical applications.

  7. Deriving optical properties of Mahakam Delta coastal waters, Indonesia using in situ measurements and ocean color model inversion

    NARCIS (Netherlands)

    Budhiman, S.; Salama, M.S.; Vekerdy, Z.; Verhoef, W.

    2012-01-01

    The development of an operational water quality monitoring method based on remote sensing data requires information on the apparent and inherent optical properties of water (AOP and IOP respectively). This study was performed to determine the apparent and inherent optical properties of coastal

  8. Three-dimensional power Doppler sonography in screening for carotid artery disease.

    Science.gov (United States)

    Keberle, M; Jenett, M; Beissert, M; Jahns, R; Haerten, R; Hahn, D

    2000-01-01

    Color Doppler sonography has gained considerable recognition as a noninvasive method to detect carotid artery disease and to assess the degree of carotid artery stenosis. However, results are highly operator-dependent and cannot be presented as survey images. The purpose of this study was to evaluate real-time 3-dimensional (3D) power Doppler sonography as a method for screening for atherosclerosis in the carotid arteries. We prospectively screened 75 patients for carotid artery disease using both conventional color Doppler sonography and 3D power Doppler sonography, and the results from the 2 modalities were compared. A total of 150 common carotid arteries, 150 internal carotid arteries, and 150 external carotid arteries were examined utilizing a 7.5-MHz linear-array transducer combined with tissue harmonic imaging. Color Doppler sonography detected 297 normal or atherosclerotic arteries without stenosis, 57 arteries with mild (1-49%) stenosis, 41 with moderate (50-69%) stenosis, 32 with severe (70-99%) stenosis, and 9 with occlusions. The degree of stenosis determined by color Doppler sonography correlated with that determined by 3D power Doppler sonography (r = 0.982-0.998). Moreover, there was a good correlation between the measurements for both the length of the lesion and its distance from the bulb as determined by the 3D volume surveys and by color Doppler sonography (r = 0.986). The interobserver variability rate was 3.7% +/- 0.5%. Generally, the acquisition and reconstruction of the 3D data took less than 5 minutes. 3D power Doppler sonography is easy to perform and is an accurate method in screening for atherosclerotic lesions of the carotid arteries. Moreover, it provides excellent 3D volume surveys that may be helpful in the planning of surgical treatment. Copyright 2000 John Wiley & Sons, Inc.

  9. Laser color recording unit

    Science.gov (United States)

    Jung, E.

    1984-05-01

    A color recording unit was designed for output and control of digitized picture data within computer controlled reproduction and picture processing systems. In order to get a color proof picture of high quality similar to a color print, together with reduced time and material consumption, a photographic color film material was exposed pixelwise by modulated laser beams of three wavelengths for red, green and blue light. Components of different manufacturers for lasers, acousto-optic modulators and polygon mirrors were tested, also different recording methods as (continuous tone mode or screened mode and with a drum or flatbed recording principle). Besides the application for the graphic arts - the proof recorder CPR 403 with continuous tone color recording with a drum scanner - such a color hardcopy peripheral unit with large picture formats and high resolution can be used in medicine, communication, and satellite picture processing.

  10. Shift Colors

    Science.gov (United States)

    Publications & News Shift Colors Pages default Sign In NPC Logo Banner : Shift Colors Search Navy Personnel Command > Reference Library > Publications & News > Shift Colors Top Link Bar Navy Personnel Library Expand Reference Library Quick Launch Shift Colors Shift Colors Archives Mailing Address How to

  11. Three-dimensional laser cooling at the Doppler limit

    Science.gov (United States)

    Chang, R.; Hoendervanger, A. L.; Bouton, Q.; Fang, Y.; Klafka, T.; Audo, K.; Aspect, A.; Westbrook, C. I.; Clément, D.

    2014-12-01

    Many predictions of Doppler-cooling theory of two-level atoms have never been verified in a three-dimensional geometry, including the celebrated minimum achievable temperature ℏ Γ /2 kB , where Γ is the transition linewidth. Here we show that, despite their degenerate level structure, we can use helium-4 atoms to achieve a situation in which these predictions can be verified. We make measurements of atomic temperatures, magneto-optical trap sizes, and the sensitivity of optical molasses to a power imbalance in the laser beams, finding excellent agreement with Doppler theory. We show that the special properties of helium, particularly its small mass and narrow transition linewidth, prevent effective sub-Doppler cooling with red-detuned optical molasses. This discussion can be generalized to identify when a given species is likely to be subject to the same limitation.

  12. Neuropathies of the optic nerve and visual evoked potentials with special reference to color vision and differential light threshold measured with the computer perimeter OCTOPUS.

    Science.gov (United States)

    Wildberger, H

    1984-10-31

    The contrast evoked potentials (VEPs) to different check sizes were recorded in about 200 cases of discrete optic neuropathies (ON) of different origin. Differential light threshold (DLT) was tested with the computer perimeter OCTOPUS. Saturated and desaturated tests were applied to evaluate the degree of acquired color vision deficiency. Delayed VEP responses are not confined to optic neuritis (RBN) alone and the different latency times obtained from other ON are confluent. The delay may be due to demyelination, to an increasing dominance of paramacular VEP subcomponents or to an increasing dominance of the upper half-field responses. Recording with smaller check sizes has the advantage that discrete dysfunctions in the visual field (VF) center are more easily detected: a correlation between amplitudes and visual acuity is best in strabismic amblyopias, is less expressed in maculopathies of the retina and weak in ON. The absence or reduction of amplitudes to smaller check sizes, however, is an important indication of a disorder in the VF center of ON in an early or recovered stage. Acquired color vision defects of the tritan-like type are more confined to discrete ON, whereas the red/green type is reserved to more severe ON. The DLT of the VF center is reduced in a different, significant and non significant extent in discrete optic neuropathies and the correlation between DLT and visual acuity is weak. A careful numerical analysis is needed in types of discrete ON where the central DLT lies within normal statistical limits: a side difference of the DLT between the affected and the normal fellow eye is always present. Evaluation of visual fatigue effects and of the relative sensitivity loss of VF center and VF periphery may provide further diagnostic information.

  13. The Use of Color Sensors for Spectrographic Calibration

    Science.gov (United States)

    Thomas, Neil B.

    2018-04-01

    The wavelength calibration of spectrographs is an essential but challenging task in many disciplines. Calibration is traditionally accomplished by imaging the spectrum of a light source containing features that are known to appear at certain wavelengths and mapping them to their location on the sensor. This is typically required in conjunction with each scientific observation to account for mechanical and optical variations of the instrument over time, which may span years for certain projects. The method presented here investigates the usage of color itself instead of spectral features to calibrate a spectrograph. The primary advantage of such a calibration is that any broad-spectrum light source such as the sky or an incandescent bulb is suitable. This method allows for calibration using the full optical pathway of the instrument instead of incorporating separate calibration equipment that may introduce errors. This paper focuses on the potential for color calibration in the field of radial velocity astronomy, in which instruments must be finely calibrated for long periods of time to detect tiny Doppler wavelength shifts. This method is not restricted to radial velocity, however, and may find application in any field requiring calibrated spectrometers such as sea water analysis, cellular biology, chemistry, atmospheric studies, and so on. This paper demonstrates that color sensors have the potential to provide calibration with greatly reduced complexity.

  14. Doppler-musical instrument

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T.J. [National Research Institute for Metals, Tsukuba, Ibaraki (Japan); Watanabe, N. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Shibata, K. [Institute for Materials Research, Tohoku Univ., Sendai, Miyagi (Japan)

    2001-03-01

    We propose a possible ultra-high energy resolution backscattering spectrometer optimized to spallation neutron source. A combination of multi monochromator crystal and Doppler drive provides considerable neutron flux, together with the reasonable energy range -30 < E < 30 {mu}eV, even when the ultra-high energy resolution of {delta}E{approx}0.03 {mu}eV is attained. (author)

  15. Color Memory

    OpenAIRE

    Pate, Monica; Raclariu, Ana-Maria; Strominger, Andrew

    2017-01-01

    A transient color flux across null infinity in classical Yang-Mills theory is considered. It is shown that a pair of test `quarks' initially in a color singlet generically acquire net color as a result of the flux. A nonlinear formula is derived for the relative color rotation of the quarks. For weak color flux the formula linearizes to the Fourier transform of the soft gluon theorem. This color memory effect is the Yang-Mills analog of the gravitational memory effect.

  16. Validating MODIS Above-Cloud Aerosol Optical Depth Retrieved from Color Ratio Algorithm Using Direct Measurements Made by NASA's Airborne AATS and 4STAR Sensors

    Science.gov (United States)

    Jethva, Hiren; Torres, Omar; Remer, Lorraine; Redemann, Jens; Livingston, John; Dunagan, Stephen; Shinozuka, Yohei; Kacenelenbogen, Meloe; Segal Rozenhaimer, Michal; Spurr, Rob

    2016-01-01

    We present the validation analysis of above-cloud aerosol optical depth (ACAOD) retrieved from the color ratio method applied to MODIS cloudy-sky reflectance measurements using the limited direct measurements made by NASAs airborne Ames Airborne Tracking Sunphotometer (AATS) and Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) sensors. A thorough search of the airborne database collection revealed a total of five significant events in which an airborne sun photometer, coincident with the MODIS overpass, observed partially absorbing aerosols emitted from agricultural biomass burning, dust, and wildfires over a low-level cloud deck during SAFARI-2000, ACE-ASIA 2001, and SEAC4RS 2013 campaigns, respectively. The co-located satellite-airborne match ups revealed a good agreement (root-mean-square difference less than 0.1), with most match ups falling within the estimated uncertainties associated with the MODIS retrievals (about -10 to +50 ). The co-retrieved cloud optical depth was comparable to that of the MODIS operational cloud product for ACE-ASIA and SEAC4RS, however, higher by 30-50% for the SAFARI-2000 case study. The reason for this discrepancy could be attributed to the distinct aerosol optical properties encountered during respective campaigns. A brief discussion on the sources of uncertainty in the satellite-based ACAOD retrieval and co-location procedure is presented. Field experiments dedicated to making direct measurements of aerosols above cloud are needed for the extensive validation of satellite based retrievals.

  17. ICALEO '89 - Optical methods in flow and particle diagnostics; Proceedings of the Meeting, Orlando, FL, Oct. 15-20, 1989

    Science.gov (United States)

    Long, Marshall B.

    Various papers on optical methods in flow and particle diagnostics are presented. Individual topics addressed include: swirl effects on confined flows in a model of a dump combustor, new analog optical method for data evaluation in laser Doppler anemometry, catadioptric optics for laser Doppler velocimeter applications, mapping of velocity flow field using the laser two-focus technique, engineering applications of particle image velocimeters, quantitative fluid flow analysis by laser velocimetry and numerical processing, optical analysis of particle image velocimetry data. Also discussed are: measuring turbulence in reversing flows by particle image velocimeter, two-color particle velocimetry, data evaluation in particle image velocimetry using spatial light modulator, statistical investigation of errors in particle image velocimetry, optimization of particle image velocimeters, visualization of internal structure in volumetric data, scalar measurements in two, three, and four dimensions.

  18. Optical trapping of cold neutral atoms using a two-color evanescent light field around a carbon nanotube

    International Nuclear Information System (INIS)

    Nga, Do Thi; Viet, Nguyen Ai; Nga, Dao Thi Thuy; Lan, Nguyen Thi Phuong

    2014-01-01

    We suggest a new schema of trapping cold atoms using a two-color evanescent light field around a carbon nanotube. The two light fields circularly polarized sending through a carbon nanotube generates an evanescent wave around this nanotube. By evanescent effect, the wave decays away from the nanotube producing a set of trapping minima of the total potential in the transverse plane as a ring around the nanotube. This schema allows capture of atoms to a cylindrical shell around the nanotube. We consider some possible boundary conditions leading to the non-trivial bound state solution. Our result will be compared to some recent trapping models and our previous trapping models.

  19. Temperature measurement of plasma-assisted flames: comparison between optical emission spectroscopy and 2-color laser induced fluorescence techniques

    KAUST Repository

    Lacoste, Deanna A.

    2015-03-30

    Accurate thermometry of highly reactive environments, such as plasma-assisted combustion, is challenging. With the help of conical laminar premixed methane-air flames, this study compares two thermometry techniques for the temperature determination in a combustion front enhanced by nanosecond repetitively pulsed (NRP) plasma discharges. Based on emission spectroscopic analysis, the results show that the rotational temperature of CH(A) gives a reasonable estimate for the adiabatic flame temperature, only for lean and stoichiometric conditions. The rotational temperature of N2(C) is found to significantly underestimate the flame temperature. The 2-color OH-PLIF technique gives correct values of the flame temperature.

  20. Temperature measurement of plasma-assisted flames: comparison between optical emission spectroscopy and 2-color laser induced fluorescence techniques

    KAUST Repository

    Lacoste, Deanna A.; Heitz, Sylvain A.; Moeck, Jonas P.

    2015-01-01

    Accurate thermometry of highly reactive environments, such as plasma-assisted combustion, is challenging. With the help of conical laminar premixed methane-air flames, this study compares two thermometry techniques for the temperature determination in a combustion front enhanced by nanosecond repetitively pulsed (NRP) plasma discharges. Based on emission spectroscopic analysis, the results show that the rotational temperature of CH(A) gives a reasonable estimate for the adiabatic flame temperature, only for lean and stoichiometric conditions. The rotational temperature of N2(C) is found to significantly underestimate the flame temperature. The 2-color OH-PLIF technique gives correct values of the flame temperature.

  1. Sol-hydrothermal synthesis and optical properties of Eu3+, Tb(3+)-codoped one-dimensional strontium germanate full color nano-phosphors.

    Science.gov (United States)

    Lin, Liangwu; Sun, Xinyuan; Jiang, Yao; He, Yuehui

    2013-12-21

    Novel near-UV and blue excited Eu(3+), Tb(3+)-codoped one dimensional strontium germanate full-color nano-phosphors have been successfully synthesized by a simple sol-hydrothermal method. The morphologies, internal structures, chemical constitution and optical properties of the resulting samples were characterized using FE-SEM, TEM, HRTEM, EDS, XRD, FTIR, XPS, PL and PLE spectroscopy and luminescence decay curves. The results suggested that the obtained Eu(3+), Tb(3+)-codoped strontium germanate nanowires are single crystal nanowires with a diameter ranging from 10 to 80 nm, average diameter of around 30 nm and the length ranging from tens to hundreds micrometers. The results of PL and PLE spectra indicated that the Eu(3+), Tb(3+)-codoped single crystal strontium germanate nanowires showed an intensive blue, blue-green, green, orange and red or green, orange and red light emission under excitation at 350-380 nm and 485 nm, respectively, which may attributed to the coexistent Eu(3+), Eu(2+) and Tb(3+) ions, and the defects located in the strontium germanate nanowires. A possible mechanism of energy transfer among the host, Eu(3+) and Tb(3+) ions was proposed. White-emission can be realized in a single-phase strontium germanate nanowire host by codoping with Tb(3+) and Eu(3+) ions. The Eu(3+), Tb(3+)-codoped one-dimensional strontium germanate full-color nano-phosphors have superior stability under electron bombardment. Because of their strong PL intensity, good CIE chromaticity and stability, the novel 1D strontium germanate full-color nano-phosphors have potential applications in W-LEDs.

  2. SEVEN-YEAR MULTI-COLOR OPTICAL MONITORING OF BL LACERTAE OBJECT S5 0716+714

    Energy Technology Data Exchange (ETDEWEB)

    Dai Yan; Wu Jianghua; Zhu Zonghong; Wang Lingzhi [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); Zhou Xu; Ma Jun [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Beijing 100012 (China); Yuan Qirong, E-mail: zhuzh@bnu.edu.cn [Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing 210046 (China)

    2013-02-15

    We have monitored the BL Lacertae object S5 0716+714 in five intermediate optical wavebands from 2004 September to 2011 April. Here, we present data that include 8661 measurements representing one of the largest databases obtained for an object in the optical domain. A simple analysis of the data indicates that the object was active most of the time, and intraday variability was frequently observed. In total, the object varied by 2.614 mag in the i band. Strong bluer-when-brighter chromatism was observed on long, intermediate, and short timescales.

  3. Physics of structural colors

    International Nuclear Information System (INIS)

    Kinoshita, S; Yoshioka, S; Miyazaki, J

    2008-01-01

    In recent years, structural colors have attracted great attention in a wide variety of research fields. This is because they are originated from complex interaction between light and sophisticated nanostructures generated in the natural world. In addition, their inherent regular structures are one of the most conspicuous examples of non-equilibrium order formation. Structural colors are deeply connected with recent rapidly growing fields of photonics and have been extensively studied to clarify their peculiar optical phenomena. Their mechanisms are, in principle, of a purely physical origin, which differs considerably from the ordinary coloration mechanisms such as in pigments, dyes and metals, where the colors are produced by virtue of the energy consumption of light. It is generally recognized that structural colors are mainly based on several elementary optical processes including thin-layer interference, diffraction grating, light scattering, photonic crystals and so on. However, in nature, these processes are somehow mixed together to produce complex optical phenomena. In many cases, they are combined with the irregularity of the structure to produce the diffusive nature of the reflected light, while in some cases they are accompanied by large-scale structures to generate the macroscopic effect on the coloration. Further, it is well known that structural colors cooperate with pigmentary colors to enhance or to reduce the brilliancy and to produce special effects. Thus, structure-based optical phenomena in nature appear to be quite multi-functional, the variety of which is far beyond our understanding. In this article, we overview these phenomena appearing particularly in the diversity of the animal world, to shed light on this rapidly developing research field

  4. Color Laser Microscope

    Science.gov (United States)

    Awamura, D.; Ode, T.; Yonezawa, M.

    1987-04-01

    A color laser microscope utilizing a new color laser imaging system has been developed for the visual inspection of semiconductors. The light source, produced by three lasers (Red; He-Ne, Green; Ar, Blue; He-Cd), is deflected horizontally by an AOD (Acoustic Optical Deflector) and vertically by a vibration mirror. The laser beam is focused in a small spot which is scanned over the sample at high speed. The light reflected back from the sample is reformed to contain linear information by returning to the original vibration mirror. The linear light is guided to the CCD image sensor where it is converted into a video signal. Individual CCD image sensors are used for each of the three R, G, or B color image signals. The confocal optical system with its laser light source yields a color TV monitor image with no flaring and a much sharper resolution than that of the conventional optical microscope. The AOD makes possible a high speed laser scan and a NTSC or PAL TV video signal is produced in real time without any video memory. Since the light source is composed of R, G, and B laser beams, color separation superior to that of white light illumination is achieved. Because of the photometric linearity of the image detector, the R, G, and B outputs of the system are most suitably used for hue analysis. The CCD linear image sensors in the optical system produce no geometrical distortion, and good color registration is available principally. The output signal can be used for high accuracy line width measuring. The many features of the color laser microscope make it ideally suited for the visual inspection of semiconductor processing. A number of these systems have already been installed in such a capacity. The Color Laser Microscope can also be a very useful tool for the fields of material engineering and biotechnology.

  5. The Trojan Color Conundrum

    Science.gov (United States)

    Jewitt, David

    2018-02-01

    The Trojan asteroids of Jupiter and Neptune are likely to have been captured from original heliocentric orbits in the dynamically excited (“hot”) population of the Kuiper Belt. However, it has long been known that the optical color distributions of the Jovian Trojans and the hot population are not alike. This difference has been reconciled with the capture hypothesis by assuming that the Trojans were resurfaced (for example, by sublimation of near-surface volatiles) upon inward migration from the Kuiper Belt (where blackbody temperatures are ∼40 K) to Jupiter’s orbit (∼125 K). Here, we examine the optical color distribution of the Neptunian Trojans using a combination of new optical photometry and published data. We find a color distribution that is statistically indistinguishable from that of the Jovian Trojans but unlike any sub-population in the Kuiper Belt. This result is puzzling, because the Neptunian Trojans are very cold (blackbody temperature ∼50 K) and a thermal process acting to modify the surface colors at Neptune’s distance would also affect the Kuiper Belt objects beyond, where the temperatures are nearly identical. The distinctive color distributions of the Jovian and Neptunian Trojans thus present us with a conundrum: they are very similar to each other, suggesting either capture from a common source or surface modification by a common process. However, the color distributions differ from any plausible common source population, and there is no known modifying process that could operate equally at both Jupiter and Neptune.

  6. Principles of doppler tomography

    International Nuclear Information System (INIS)

    Juhlin, P.

    1992-08-01

    This paper shows how the radon transform can be used to determine vector fields. A scheme to determine the velocity field of a moving fluid by measurements with a continuous doppler signal is suggested. When the flow is confined to a bounded domain, as is the case in most applications, it can be uniquely decomposed into one gradiental and one rotational part. The former vanishes if the fluid is incompressible and source-free, and the latter can be completely reconstructed by the methods proposed in this paper if the domain is simply connected. Special attention is paid to laminar flow in a long cylindrical vessel with circular cross-section. Under such conditions the flow profile becomes parabolic, which makes the vessel recognizable as a typical 'N-shaped' pattern in an image describing the rotation of the velocity field. The vessel yields the same doppler tomographic pattern, no matter how it is sectioned. The ideas presented should be applicable also when studying the flow in blood vessels, even if the flow profile in these is not quite parabolic. The discrepancies only make the 'N-shape' somewhat distorted

  7. Comparisons between PW Doppler system and enhanced FM Doppler system

    DEFF Research Database (Denmark)

    Wilhjelm, Jens E.; Pedersen, P. C.

    1995-01-01

    This paper presents a new implementation of an echo-ranging FM Doppler system with improved performance, relative to the FM Doppler system reported previously. The use of long sweeps provides a significant reduction in peak to average power ratio compared to pulsed wave (PW) emission. A PW Doppler...... system exploits the direct relationship between arrival time of the received signal and range from the transducer. In the FM Doppler systems, a similar relationship exists in the spectral domain of the demodulated received signals, so that range is represented by frequency. Thus, a shift in location...... of moving scatterers between consecutive emissions corresponds to a frequency shift in the spectral signature. The improvement relative to the earlier version of the FM Doppler system is attained by utilizing cross-correlation of real spectra rather than of magnitude spectra for assessing flow velocity...

  8. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

  9. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... video series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... an optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

  10. Ask a Scientist: What is Color Blindness?

    Science.gov (United States)

    ... video series. Dr. Sheldon Miller answers questions about color blindness, whether it can be treated, and how people ... an optical illusion? Click to Watch What is color blindness? Click to Watch How do I become a ...

  11. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... Information Optical Illusions Printables Ask a Scientist Video Series Why can’t you see colors well in ... and more with our Ask a Scientist video series. Dr. Sheldon Miller answers questions about color blindness, ...

  12. Fractal kinetics of radiation-induced point-defect formation and decay in amorphous insulators: Application to color centers in silica-based optical fibers

    Science.gov (United States)

    Griscom, David L.

    2001-11-01

    Formalisms have been developed to express the time evolution of bimolecular processes taking place in fractal spaces. These ``stretched-second-order'' solutions are specifically applicable to radiation-induced electron-hole pairs and/or vacancy-interstitial pairs in insulating glasses. Like the analogous Kohlrausch-type (stretched-first-order) expressions, the present solutions are functions of (kt)β, where 0the new second-order formalism and the familiar Kohlrausch approach have been used to fit experimental data (induced optical absorptions in silica-based glasses monitored at selected wavelengths) that serve as proxies for the numbers of color centers created by γ irradiation and/or destroyed by processes involving thermal, optical, or γ-ray activation. Two material systems were investigated: (1) optical fibers with Ge-doped-silica cores and (2) fibers with low-OH/low-chloride pure-silica cores. Successful fits of the growth curves for the Ge-doped-silica-core fibers at four widely separated dose rates were accomplished using solutions for color-center concentrations, N[(kt)β], which approach steady-state values, Nsat, as t-->∞. The parametrization of these fits reveals some unexpected, and potentially useful, empirical rules regarding the dose-rate dependences of β, k, and Nsat in the fractal regime (0the pure-silica-core fibers as well. In both material systems, there appear to be fractal classical phase transitions at certain threshold values of dose rate, below which the dose-rate dependencies of k and Nsat revert to those specified by classical (β=1) first- or second-order kinetics. For ktthe first- and second-order fractal kinetic growth curves become identical, i.e., N((kt)β)~Atβ, where the coefficient A depends on dose rate but not kinetic order. It is found empirically that A depends on the 3β/2 power of dose rate in both first- and second-order kinetics, thus ``accidentally'' becoming linearly proportional to dose rate in cases where β~2

  13. Measurement of cylindrical particles with phase Doppler anemometry.

    Science.gov (United States)

    Mignon, H; Gréhan, G; Gouesbet, G; Xu, T H; Tropea, C

    1996-09-01

    Light scattering from cylindrical particles has been described with geometric optics. The feasibility of determining the particle diameter with a planar phase Doppler anemometer has been examined by simulations and experiments. In particular, the influence of particle orientation on measurability and measurement accuracy has been investigated. Some recommendations for realizing a practical-measurement instrument have been presented.

  14. Deconvoluting double Doppler spectra

    International Nuclear Information System (INIS)

    Ho, K.F.; Beling, C.D.; Fung, S.; Chan, K.L.; Tang, H.W.

    2001-01-01

    The successful deconvolution of data from double Doppler broadening of annihilation radiation (D-DBAR) spectroscopy is a promising area of endeavour aimed at producing momentum distributions of a quality comparable to those of the angular correlation technique. The deconvolution procedure we test in the present study is the constrained generalized least square method. Trials with computer simulated DDBAR spectra are generated and deconvoluted in order to find the best form of regularizer and the regularization parameter. For these trials the Neumann (reflective) boundary condition is used to give a single matrix operation in Fourier space. Experimental D-DBAR spectra are also subject to the same type of deconvolution after having carried out a background subtraction and using a symmetrize resolution function obtained from an 85 Sr source with wide coincidence windows. (orig.)

  15. Adaptive Spectral Doppler Estimation

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jakobsson, Andreas; Jensen, Jørgen Arendt

    2009-01-01

    . The methods can also provide better quality of the estimated power spectral density (PSD) of the blood signal. Adaptive spectral estimation techniques are known to pro- vide good spectral resolution and contrast even when the ob- servation window is very short. The 2 adaptive techniques are tested......In this paper, 2 adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound. The purpose is to minimize the observation window needed to estimate the spectrogram to provide a better temporal resolution and gain more flexibility when designing the data acquisition sequence...... and compared with the averaged periodogram (Welch’s method). The blood power spectral capon (BPC) method is based on a standard minimum variance technique adapted to account for both averaging over slow-time and depth. The blood amplitude and phase estimation technique (BAPES) is based on finding a set...

  16. Color Algebras

    Science.gov (United States)

    Mulligan, Jeffrey B.

    2017-01-01

    A color algebra refers to a system for computing sums and products of colors, analogous to additive and subtractive color mixtures. The difficulty addressed here is the fact that, because of metamerism, we cannot know with certainty the spectrum that produced a particular color solely on the basis of sensory data. Knowledge of the spectrum is not required to compute additive mixture of colors, but is critical for subtractive (multiplicative) mixture. Therefore, we cannot predict with certainty the multiplicative interactions between colors based solely on sensory data. There are two potential applications of a color algebra: first, to aid modeling phenomena of human visual perception, such as color constancy and transparency; and, second, to provide better models of the interactions of lights and surfaces for computer graphics rendering.

  17. Ocean Color

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite-derived Ocean Color Data sets from historical and currently operational NASA and International Satellite missions including the NASA Coastal Zone Color...

  18. Color naming

    OpenAIRE

    Şahin, Ebru

    1998-01-01

    Ankara : Bilkent University, Department of Interior Architecture and Environmental Design and Institute of Fine Arts, 1998. Thesis (Ph.D) -- Bilkent University, 1998 Includes bibliographical refences. In this study, visual aspects of color and neurophysiological processes involved in the phenomenon, language of color and color models were explained in addition to the discussion of different ideas, orientations and previous works behind the subject of matter. Available color ...

  19. A quantitative assessment approach of feasible optical mechanisms contributing to structural color of golden-like Chrysina aurigans scarab beetles

    International Nuclear Information System (INIS)

    Azofeifa, D.E.; Hernández-Jiménez, M.; Libby, E.; Solís, A.; Barboza-Aguilar, C.; Vargas, W.E.

    2015-01-01

    Under normal incidence of non-polarized light, reflection spectra from the cuticle of golden-like C. aurigans scarabs shows a broad band displayed from 525 to 950 nm, with a spectral ripple structure that consists of a uniform sequence of peaks superimposed on the main reflection band. Cross sectional Scanning Electron Microscope (SEM) images of the cuticle initially suggest the presence of a multilayered structure. A radiative transfer matrix formalism is first applied to describe as much as possible the main features of coherent reflection spectra, by assuming optically homogenous layers distributed through the exocuticle, with chitin as the major constituent material. Additional non-coherent multiple reflections due to layers in the endocuticle are also evaluated from this approach. The presence of a pigmented micron sized structure beneath the procuticle requires the evaluation of a diffuse light contribution to the reflection. This was carried out from a four-flux radiative transfer model. Optical anisotropy is introduced by interpreting the SEM images in terms of a twisted Bouligand-type structure, and reflection spectra are evaluated from an implementation of the so-called 4×4 Berreman's formalism. We have been able to approach the main features characterizing the reflection spectra of C. aurigans' elytra following this progressive way. - Highlights: • Polarization of light reflected by the cuticle of C. aurigans scarabs is established. • The pitch of the helical structure in the cuticle is established from SEM images. • C. aurigans is a broadband natural reflector with the wider reflection band observed

  20. Retrieval of spectral aerosol optical thickness over land using ocean color sensors MERIS and SeaWiFS

    Directory of Open Access Journals (Sweden)

    W. von Hoyningen-Huene

    2011-02-01

    Full Text Available For the dete