Color Doppler Imaging (color + doppler_imaging)

Distribution by Scientific Domains


Selected Abstracts


Pseudoexfoliatio capsulae and endothelin-1 plasma levels

ACTA OPHTHALMOLOGICA, Issue S232 2000
G. L. Possati
M. Cellini Summary The authors found an increase of endothelin-1 (ET-1) plasma levels in patients with pseudoexfoliatio syndrome (PXS): 2.730±0.224 pg/ml vs 1.420±0.30S pg/ml. With Color Doppler Imaging (CDI) they found in PXS patients a decrease of peak systolic velocity values in the posterior ciliary arteries that were 12.725 ± 2.536 cm/sec vs 15.450 ± 3.173 cm/sec (p<0.049) while the resistance values were increased 0.640 ± 0.051 vs 0.548 ± 0.058 (p<0.001). The increase of ET-1 plasma levels may assess the vasospasm and uveal tissue hypoxia. [source]


Blood Flow Imaging,A New Angle-Independent Ultrasound Modality for the Visualization of Flow in Atrial Septal Defects in Children

ECHOCARDIOGRAPHY, Issue 9 2007
Siri Ann Nyrnes M.D.
Background: Color Doppler imaging (CDI) is the most applied method for evaluation of flow in atrial septal defects (ASD). A new real time ultrasound flow imaging modality called blood flow imaging (BFI) is able to visualize the blood flow in any direction of the image and is not limited by velocity aliasing. The method thereby overcomes the two limitations most often encountered in CDI. In this study we compared BFI with CDI for the visualization of interatrial blood flow in children. Methods: We studied ASD flow in 13 children using both CDI and BFI in the same examination. CDI and BFI cineloops were prepared off-line and both optimal and suboptimal (increased color artifacts) images were presented in random order to four observers. They were asked to range from 0,100 on a visual analogue scale how certain they were of interatrial blood flow. The CDI and BFI ratings were compared using the exact Wilcoxon signed rank test for paired samples. Results: All ASDs visualized with CDI were confirmed using BFI. Two of the observers ranked BFI as being significantly better than CDI when the images were optimized. When the images were suboptimal three of the observers rated BFI as being significantly better. Conclusions: This pilot study indicates that BFI improves the visualization of interatrial blood flow in children. To include BFI in the ordinary echocardiography examination is easy and not time consuming. The method may prove to be a useful supplement to CDI in ASD imaging. [source]


Bilateral round ligament varicosities mimicking an inguinal hernia in pregnancy: Case report

JOURNAL OF CLINICAL ULTRASOUND, Issue 9 2010
Guven Kahriman
Abstract A 22-year-old pregnant woman presented with a painful swelling in the right groin. Sonography was performed to confirm a presumptive diagnosis of inguinal hernia based on physical examination. Gray-scale sonography examination revealed bilateral inguinal cystic lesion expanding with the Valsalva maneuver. Color Doppler imaging demonstrated multiple prominent vessels with retrograde venous flow during Valsalva maneuver. Bilateral round ligament varicosities were diagnosed and inguinal hernia was excluded by sonographic findings. Round ligament varicosities should be considered in the differential diagnosis of groin swelling during pregnancy. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:512,514, 2010 [source]


Insufficiency fracture of the calcaneum: Sonographic findings

JOURNAL OF CLINICAL ULTRASOUND, Issue 7 2009
Delphine Arni
Abstract We present a case of insufficiency fracture (IF) of the calcaneum diagnosed by sonography (US). An 83-year-old woman consulted because of pain and swelling of the left heel without history of trauma. Standard radiographs showed osteoporosis without fracture. US revealed thickening of the calcaneal periosteum associated with edema of the adjacent soft tissues. Color Doppler imaging showed marked increased vascularity of the periosteum. US changes, together with the clinical and radiographic findings, were consistent with an IF of the calcaneum that was confirmed by MRI. The patient was treated successfully by conservative treatment. In the proper clinical setting, US can suggest the diagnosis of IF of the calcaneum. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009 [source]


Orbital blood flow velocities in patients with rheumatoid arthritis

JOURNAL OF CLINICAL ULTRASOUND, Issue 7 2007
Besir Erdogmus MD
Abstract Purpose. To assess orbital blood flow changes in patients with rheumatoid arthritis using Doppler sonography. Patients and Methods. The study comprised 35 patients who were diagnosed with RA and were treated at the Department of Physical Therapy and Rehabilitation at Duzce Medical School. A control group consisted of 35 healthy volunteers. Color Doppler imaging was used to measure peak systolic velocity (PSV) and end diastolic velocity (EDV), from which the resistance index (RI) was calculated in the ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary arteries (PCAs). Results. In the OA, PSV, EDV, and RI were, respectively, 36.7 ± 0.6 cm/sec, 9.7 ± 0.2 cm/sec, and 0.73 in the control group versus 34.7 ± 3.0 cm/sec, 9.1 ± 1.1 cm/sec, and 0.74 in the patient group. In the CRA, they were, respectively, 11.8 ± 1.7 cm/sec, 3.6 ± 0.7 cm/sec, and 0.66 in the control group versus 11.1 ± 1.7 cm/sec, 3.4 ± 0.7 cm/sec, and 0.68 in the patient group. In the PCAs, they were, respectively, 13.2 ± 1.2 cm/sec, 4.7 ± 0.6 cm/sec, and 0.65 in the control group versus 12.4 ± 1.2 cm/sec, 4.2 ± 0.6 cm/sec, and 0.66 in the PCAs. PSV, EDV, and RI of the PCAs and OA and RI of the CRA were significantly different between patients and controls, whereas there was no difference in the serum levels of glucose, triglyceride, low-density lipoprotein cholesterol, and total cholesterol. In the patient group, there was a significant correlation between orbital blood flow and duration of disease. Conclusion. Ocular blood flow appears to be slightly lower in RA patients than in healthy controls, suggesting that RA is a systemic inflammatory disease that may also involve ocular vessels. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007 [source]


Ophthalmic artery blood flow velocity changes in diabetic patients as a manifestation of macroangiopathy

ACTA OPHTHALMOLOGICA, Issue 2 2000
Masanori Ino-ue
ABSTRACT. Purpose: The hemodynamic characteristics of ophthalmic artery (OA) blood flow velocity in diabetic patients with ocular involvement were evaluated. Methods: Changes in OA blood flow of eyes with background diabetic retinopathy (BDR), proliferative retinopathy (PDR) and ocular ischemic syndrome (OIS) were ananalyzed by Color Doppler imaging. Results: Patients with BDR and PDR had significantly lower diastolic and mean blood flow velocities and higher pulsatility indices compared to controls. Diabetic patients with OIS had significantly lower systolic, diastolic and mean anterograde OA blood flow velocities than the controls. Pulsatility indices were higher in anterograde OA blood flow measurements compared to controls. Systolic blood flow velocities in rubeotic eyes with OIS were significantly lower than in rubeotic eyes with PDR. Conclusion: OA blood flow measurements by color doppler imaging may detect macroangiopathies in diabetic patients as manifested by carotid atheromas and arterio- and arterosclerosis of the OA and its branches. [source]


Color doppler imaging in the sonohysterographic diagnosis of residual trophoblastic tissue

JOURNAL OF CLINICAL ULTRASOUND, Issue 4 2002
Yaron Zalel MD
Abstract Purpose The purpose of this study was to evaluate the role of color Doppler imaging during sonohysterography in the diagnosis of residual trophoblastic tissue. Methods This prospective cohort study involved 25 consecutive women with clinical and sonographic signs of an echogenic intrauterine mass who were referred to the sonography unit of our institution for evaluation. All women underwent saline infusion sonohysterography with color Doppler sonographic evaluation. An operative hysteroscopy with histologic examination was performed in 17 cases. Results Thirteen women (group A) had sonohysterographic features suggestive of residual tropho- blastic tissue (ie, an echogenic intrauterine lesion not detached from the uterine wall after introduction of saline). The initial diagnosis was confirmed by histologic analysis in all cases. Blood flow was detected within the intrauterine mass in 6 (46%) of these 13 women; the resistance indices were low in all 6 cases (mean ± standard error, 0.38 ± 0.01). Twelve women (group B) had sonohysterographic findings negative for retained tissue, and no blood flow was detected within any of the intrauterine masses in this group (p < 0.05). Conclusions Our results confirm the potential role of color Doppler sonography in the initial diagnosis of residual trophoblastic tissue. The detection of color Doppler signals, especially with low-resistance flow, within an intrauterine lesion should increase the confidence of the sonologist in the diagnosis of residual trophoblastic tissue. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30: 222,225, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10059 [source]


Fetal Mouse Imaging Using Echocardiography: A Review of Current Technology

ECHOCARDIOGRAPHY, Issue 10 2006
Christopher F. Spurney M.D.
Advances in genetic research have led to the need for phenotypic analysis of small animal models. However, often these genetic alterations, especially when affecting the cardiovascular system, can result in fetal or perinatal death. Noninvasive ultrasound imaging is an ideal method for detecting and studying such congenital malformations, as it allows early recognition of abnormalities in the living fetus and the progression of disease can be followed in utero with longitudinal studies. Two platforms for fetal mouse echocardiography exist, the clinical systems with 15-MHz phased array transducers and research systems with 20,55-MHz mechanical transducers. The clinical ultrasound system has limited two-dimensional (2D) resolution (axial resolution of 440 ,m), but the availability of color and spectral Doppler allows quick interrogations of blood flows, facilitating the detection of structural abnormalities. M-mode imaging further provides important functional data, although, the proper imaging planes are often difficult to obtain. In comparison, the research biomicroscope system has significantly improved 2D resolution (axial resolution of 28 ,m). Spectral Doppler imaging is also available, but in the absence of color Doppler, imaging times are increased and the detection of flow abnormalities is more difficult. M-mode imaging is available and equivalent to the clinical ultrasound system. Overall, the research system, given its higher 2D resolution, is best suited for in-depth analysis of mouse fetal cardiovascular structure and function, while the clinical ultrasound systems, equipped with phase array transducers and color Doppler imaging, are ideal for high-throughput fetal cardiovascular screens. [source]


Serum bFGF and VEGF correlate respectively with bowel wall thickness and intramural blood flow in Crohn's disease

INFLAMMATORY BOWEL DISEASES, Issue 5 2004
Dr. Antonio Di Sabatino MD
Abstract Serum levels of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF),two factors known to promote tissue repair, fibroblast proliferation, and angiogenesis,were measured in Crohn's disease patients and correlated with bowel wall thickness (BWT), measured by conventional grey scale ultrasonography, and with the ileal intramural vessel flow, measured by contrast-enhanced color Doppler imaging. Serum samples were obtained from 25 patients with active Crohn's disease and 22 healthy volunteers, all sex- and age-matched. Serum bFGF and VEGF levels were measured by ELISA assay. All the patients were examined with conventional transabdominal bowel sonography. Color Doppler of the intramural enteric vessels was then performed after the intravenous injection of Levovist, a galactose-based sonographic contrast agent. In Crohn's disease patients, serum bFGF and VEGF were significantly higher compared with healthy volunteers. A positive correlation between serum bFGF and BWT and between serum VEGF and color Doppler signal intensity was found. The raised serum bFGF levels in Crohn's disease patients with intestinal strictures compared with patients with other phenotypes (fistulizing, inflammatory), together with the correlation observed between serum bFGF and BWT, suggests a possible involvement of bFGF in the process of transmural fibrogenesis in Crohn's disease. The higher levels of VEGF in those patients with increased intramural blood flow suggests that VEGF may be considered a marker of angiogenesis in this condition. [source]


Effects of intravitreal bevacizumab (Avastin®) therapy on retrobulbar blood flow parameters in patients with neovascular age-related macular degeneration

JOURNAL OF CLINICAL ULTRASOUND, Issue 2 2010
Ahmet Mete MD
Abstract Background. To investigate the effects of intravitreal bevacizumab on retrobulbar circulation in patients with neovascular age-related macular degeneration (AMD). Method. Thirty patients with neovascular age-related macular degeneration were assessed prospectively by both color Doppler imaging and fundus fluorescein angiography. Spectral Doppler analysis allowed the measurement of the maximum velocity (Vmax) and minimum velocity (Vmin) of the central retinal vein (CRV), and peak systolic (PSV), end-diastolic (EDV) velocities of blood flows, and pulsatility index (PI) and resistance index (RI) values in the central retinal artery (CRA), nasal and temporal posterior ciliary arteries (NPCA, TPCA), and ophthalmic artery (OA). The t test for paired samples was used to compare retrobulbar blood flow values before and after intravitreal bevacizumab injection. Result. PSV and EDV of the NPCA and PSV of the TPCA were significantly decreased after intravitreal bevacizumab injection (p < 0.05). There was no statistically significant difference in the other parameters. Conclusion. Our results suggest that intravitreal bevacizumab therapy has a measurable effect on retrobulbar blood flow. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2010 [source]


Sonographic appearance of angiolymphoid hyperplasia with eosinophilia in the upper arm

JOURNAL OF CLINICAL ULTRASOUND, Issue 7 2008
Chee-Wai Mak MD
Abstract Angiolymphoid hyperplasia with eosinophilia is an uncommon benign condition characterized by cutaneous nodules involving primarily the head and neck regions of young adults. We report thecase of a 49-year-old woman with such a lesion in the arm. Sonographically, the lesion exhibited a hypoechoic rim and an echogenic central portion. On color Doppler imaging, the central portion was markedly vascular. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008. [source]


Sonographic spectrum of scrotal abnormalities in infertile men

JOURNAL OF CLINICAL ULTRASOUND, Issue 8 2007
Hussein S. Qublan
Abstract Purpose. To use sonography to detect scrotal abnormalities in infertile men. Material and Methods. Two hundred thirty-four infertile men, including 176 oligospermic (sperm count < 10 × 106/ml), 58 azoospermic, and 150 normospermic men (control group) were evaluated prospectively for the presence of intra- and extratesticular abnormalities using high-frequency transducers and color Doppler imaging. Medical and surgical history, testicular volume, semen parameters, and hormonal levels were recorded. Results. A statistically significant increase in the prevalence of abnormal scrotal findings detected with sonography was observed in the study group compared with controls. These included variocele in 35.5% versus 16% (p < 0.01), hydrocele in 16.7% versus 8.7% (p < 0.05), testicular microlithiasis in 9.8% versus 2% (p < 0.01), epididymal enlargement in 9% versus 2.6% (p < 0.05), and epididymal cyst in 7.7% versus 2% (p < 0.05). Testicular tumor was not seen in either group. A statistically significant decrease in testicular volume, sperm concentration, normal morphology, and forward motility of the sperm was noted in the study group compared with controls (p < 0.01). Conclusion. The various intra- and extratesticular abnormalities were demonstrated in infertile men. Sonography should be used routinely in the work-up of male infertility. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007 [source]


Spontaneous nontraumatic intrasplenic pseudoaneurysm: Causes, sonographic diagnosis, and prognosis

JOURNAL OF CLINICAL ULTRASOUND, Issue 3 2003
Christian Görg MD
Abstract Purpose The aim of this study was to describe the incidence, causes, sonographic features, therapy, and prognosis of nontraumatic intrasplenic pseudoaneurysms (NTISPs), a rare complication of splenic infarction or infiltration by malignant systemic disorders or infectious diseases. Methods We retrospectively reviewed the medical and sonographic records of all patients seen at our clinic from July 1985 through December 2000 to identify patients with a sonographic diagnosis of spontaneous nontraumatic splenic rupture. We then examined the features of the resulting cases to identify patients in whom NTISPs were revealed by color Doppler sonography. Results In total, 41 patients were identified. Among those patients, 5 (12%) had NTISPs. Three of those 5 patients had an underlying malignant disorder (1 case of non-Hodgkin's lymphoma and 2 cases of chronic myelogenous leukemia), and the other 2 had an inflammatory disease (1 case of endocarditis and 1 case of pancreatitis). Three of the patients also had splenic infarctions. Three patients underwent splenectomy; in 2 of them, secondary delayed splenic rupture occurred before or during splenectomy. In 2 other patients, spontaneous thrombosis of the aneurysms occurred (after 16 hours in 1 and 15 days in the other). Conclusions NTISPs may occur in about 12% of patients with sonographically detected nontraumatic spontaneous splenic rupture. NTISPs appear to be associated with an increased risk of secondary delayed splenic rupture, although spontaneous thrombosis may occur. Short-term follow-up sonographic examinations, particularly with color Doppler imaging, are recommended for early recognition of progression of NTISPs, which can guide treatment decisions. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:129,134, 2003 [source]


Observer experience improves reproducibility of color doppler sonography of orbital blood vessels

JOURNAL OF CLINICAL ULTRASOUND, Issue 6 2002
János Németh MD
Abstract Purpose. The study investigated the reproducibility of orbital blood flow measurements with color Doppler imaging (CDI) at different stages of observer experience. Methods. The subjects were 31 healthy volunteers and 2 sequential groups of 25 glaucoma patients each. Repeated blood flow measurements (usually 3 sets) in orbital vessels (ophthalmic artery, short posterior ciliary arteries, central retinal artery, and central retinal vein) were performed by the same observer in a single session in each subject. Results. The parameters with the best reproducibility were the resistance index (mean coefficient of variation [COV], 3.3,8.8%), the peak systolic velocity (mean COV, 6.9,13.7%), the time-averaged velocity (mean COV, 7.2,16.0%), and the systolic acceleration time (mean COV, 8.8,12.3%). The mean COV was greater (9.9,20.3%) for the other arterial flow parameters (end-diastolic velocity and systolic acceleration) and for the venous flow velocities (maximum and minimum). The COVs of the parameters were improved by 20,40% as the observer became more experienced in ophthalmic CDI. Conclusions. We confirm the general reliability of CDI measurements in orbital vessels and show that observer experience improves reproducibility. It appears, however, that observer performance in these measurements is vessel specific. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:332,335, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10079 [source]


Role of color Doppler imaging in diagnosing and managing pregnancies complicated by placental chorioangioma

JOURNAL OF CLINICAL ULTRASOUND, Issue 5 2002
Yaron Zalel MD
Abstract Purpose The purpose of this study was to evaluate the role of color Doppler imaging in the diagnosis and management of placental chorioangioma. Methods The medical records, sonographic reports, and sonograms of all pregnant women who had placental masses diagnosed in our sonography unit during the years 1992 through 2000 and had been evaluated using both gray-scale and color Doppler sonography were included in this study. Subjective evaluation of the amount and distribution of intralesional vascularity by color Doppler imaging was made in all cases. Cases of chorioangioma of the placenta were compared with cases of placental hemorrhage or subchorionic hematoma. The outcomes of the pregnancies were also recorded. Results Fifteen cases of placental masses were evaluated; 8 of them were identified as placental hemorrhage or subchorionic hematoma on the basis of the sonographic findings. The other 7 cases were identified prenatally as placental chorioangioma, at a mean menstrual age of 23 weeks and a mean maternal age of 29 years. The mean size of the tumor was 6.5 cm (range, 4,13 cm). All cases of chorioangioma showed either substantial internal vascularity or a large feeding vessel within the tumor. Three infants were delivered at term with favorable outcome; 2 of them demonstrated reduction of the intratumoral blood flow during follow-up. The other 4 cases were delivered at or before 32 weeks' menstrual age (1 intrauterine fetal death, 2 terminated pregnancies, and 1 normal infant). No case of placental hematoma demonstrated blood flow within the lesion or was associated with complications of the pregnancy. Conclusions Color Doppler imaging helps differentiate placental chorioangioma from other placental lesions and may be useful in the prenatal follow-up of chorioangioma. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:264,269, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10072 [source]


Color doppler imaging in the sonohysterographic diagnosis of residual trophoblastic tissue

JOURNAL OF CLINICAL ULTRASOUND, Issue 4 2002
Yaron Zalel MD
Abstract Purpose The purpose of this study was to evaluate the role of color Doppler imaging during sonohysterography in the diagnosis of residual trophoblastic tissue. Methods This prospective cohort study involved 25 consecutive women with clinical and sonographic signs of an echogenic intrauterine mass who were referred to the sonography unit of our institution for evaluation. All women underwent saline infusion sonohysterography with color Doppler sonographic evaluation. An operative hysteroscopy with histologic examination was performed in 17 cases. Results Thirteen women (group A) had sonohysterographic features suggestive of residual tropho- blastic tissue (ie, an echogenic intrauterine lesion not detached from the uterine wall after introduction of saline). The initial diagnosis was confirmed by histologic analysis in all cases. Blood flow was detected within the intrauterine mass in 6 (46%) of these 13 women; the resistance indices were low in all 6 cases (mean ± standard error, 0.38 ± 0.01). Twelve women (group B) had sonohysterographic findings negative for retained tissue, and no blood flow was detected within any of the intrauterine masses in this group (p < 0.05). Conclusions Our results confirm the potential role of color Doppler sonography in the initial diagnosis of residual trophoblastic tissue. The detection of color Doppler signals, especially with low-resistance flow, within an intrauterine lesion should increase the confidence of the sonologist in the diagnosis of residual trophoblastic tissue. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30: 222,225, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10059 [source]


Correlation of color Doppler sonographic findings with pH measurements in gastroesophageal reflux in children

JOURNAL OF CLINICAL ULTRASOUND, Issue 4 2001
Hye Suk Jang MD
Abstract Purpose We conducted a prospective study of color Doppler sonography in children with suspected gastroesophageal reflux (GER). The purpose of this study was to compare the accuracy of color Doppler sonography with that of continuous 24-hour pH monitoring of the esophagus in diagnosing GER and to determine how to interpret the reflux episodes detected on color Doppler sonography in children at high risk for reflux. Methods Color Doppler sonography and 24-hour esophageal pH monitoring were performed in 54 children ranging in age from 2 months to 10 years (mean, 3 years). The stomach of each patient was filled for adequate gastric distention just before the color Doppler sonographic examination. We counted the number of reflux episodes over a period of 15 minutes. One day after the sonographic examination, the reflux was evaluated with esophageal pH monitoring, and the resultant reflux index (ReI) was obtained. The ReI was considered to be pathologic when it was equal to or greater than 11.99%. The number of refluxes on color Doppler sonography and the ReI were correlated for each patient. Results The 2 tests showed an 81.5% agreement in the detection of GER. When pH monitoring was taken as the reference test, color Doppler sonography had a high sensitivity (95.5%) for diagnosing GER but a very low specificity (11.0%), with a positive predictive value of 84.3% and a negative predictive value of 33.3%. There was no statistically significant correlation between the frequencies of GER detected on color Doppler sonography and the ReIs on pH monitoring (p = 0.1103). There was no correlation between the reflux grades on sonography and the ReI grades on pH monitoring (p = 0.422). Conclusions Color Doppler sonography is highly sensitive and easier to use than pH monitoring. Although there are no definite criteria for evaluating the severity of GER on color Doppler imaging, this modality may be useful in screening children for GER. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:212,217, 2001. [source]


A Comparative Study of Intraplacental Villous Arteries by Latex Cast Model in vitro and Color Doppler Flow Imaging in vivo,

JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2001
Junwu Mu
Abstract Objective: The purpose of this study was to determine whether color Doppler sonogram can accurately depict the placental vascular structures using a latex cast model of the placental vessels, and to make a nomogram of several blood flow parameters according to the vascular structures. Methods: First, we made 9 latex cast models of placental arteries and performed morphologic observation and measurement. Second, the comparative anatomical observation of placental vessels by color flow mapping was performed for all 9 patients from whom the latex models were made. Third, a total of 102 uncomplicated pregnant women between 18 and 40 weeks gestation were examined by color Doppler imaging. The resistance indices (RI) and peak systolic velocity (PSV) were measured. Results: In the latex cast model of placentas, cotyledons could be differentiated by the presence of independent vascular structure units. First, second, third and fourth branches were noted in one cotyledon. Cotyledons were easily identified and counted by color Doppler imaging. Each cotyledon contained only one first branch of the intraplacental villous artery (IPVA). The number of IPVA-1 on color Doppler imaging was equal to the number of the cotyledon calculated from the latex model. RI exhibited a negative, and PSV a positive correlation with gestational age (p < 0.05 in both cases). At any given gestational age, both RI and PSV in the peripheral arteries were significantly lower (p < 0.01) than those in the upstream arteries. Conclusions: Color Doppler flow sonography is a valuable tool for detecting the blood flow of intraplacental villous arteries in vivo and the images agree with the vascular anatomy of placenta in vitro. These results may also provide the basic parameters for future studies of some complicated pregnancies. [source]


2221: Gases and the ocular vasculature

ACTA OPHTHALMOLOGICA, Issue 2010
L SCHMETTERER
Purpose The regulation of ocular blood flow and oxygenation is largely controlled by metabolic factors. Among them gases like oxygen (O2), carbon dioxide (CO2), carbon monoxide (CO) and nitroc oxide (NO) play a key role. Methods In a series of clinical trials we focussed on the role of O2, CO2, CO and NO in the control of ocular blood flow. These studies were done on healthy subjects and employed a number of techniques including laser Doppler flowmetry, color Doppler imaging and pulsatile ocular blood flow techniques. Results O2 is a very potent vasoconstrictor in the retina and optic nerve head, but not in the choroid. The mechanisms underlying this effect is not entirely clear, but appears to involve endothelin A receptors. CO and CO2 are potent vasodilators in retina, choroid and optic nerve head. NO plays a major role in the control of basal vascular tone in all ocular vessels, but is also involved in many agonist-induced vasodilator effects. Conclusion Gases play a key role in controlling ocular blood flow. An imblanace of the production of these mediators is associated with ischemia, hypoxia and endothelial dysfunction. [source]


3254: Neurovascular coupling in the retrobulbar ciliary circulation

ACTA OPHTHALMOLOGICA, Issue 2010
O ZEITZ
Purpose Perfusion of the retina is adapted to the metabolic demand by neurovascular coupling. Neurovascular coupling has shown to be present in the retinal vasculature, but not in vessels supplying the optic nerve. The present study investigated the presence of neurovascular coupling in the anterior part of the optic nerve in healthy and glaucoma subjects. Methods Retrobulbar blood flow velocities were determined by color Doppler imaging (CDI). A Siemens Elegra ultrasound system with a 7.5L40 transducer was used. Peak-systolic and end-diastolic velocities (PSV and EDV) in the central retinal artery (CRA) or the short posterior ciliary artery (SPCA) were the primary readout. CDI measurements were performed shortly before, during, immediately after, 60 s after, and 120 s after a 10-Hz flicker stimulation of the retina. Results Thirty-five glaucoma patients and 44 healthy control subjects were included in the study. In the SPCA of healthy controls, flicker stimulation led to a rise of PSV from 9.7±0.8 to 12.5±0.8 cm/s (P<0.001; N=24) and of EDV from 2.4±0.3 to 3.6±0.3 cm/s (P<0.001; N=24). This effect was not detectable in glaucoma patients. In the CRA, flicker light led to an increase of EDV from 2.1±0.2 to 3.0±0.3 cm/s (P=0.002; N=20) in healthy volunteers and from 1.3±0.2 to 2.0±0.2 cm/s in glaucoma patients (P=0.004; N=15). PSV was affected by flicker stimulation in neither the healthy volunteers nor glaucoma patients. Conclusion The data indicate the presence of neurovascular coupling in the vascular bed supplied by the paraoptic SPCA. The response pattern to the flicker stimulus differs between healthy and glaucoma subjects. [source]


Most readily usable methods to measure ocular blood flow

ACTA OPHTHALMOLOGICA, Issue 2009
K GUGLETA
Purpose SIS Lecture. Methods Literature search. Results Ocular Blood Flow Research Association (OBFRA, recently merged with another organization - ISOCO, into one single Association for Ocular CDirculation - AOC) made a significant contribution to standardization of the blood flow measuring techniques in the field of ophthalmology. A consens was reached on the number of OBF measurements techniques that occured in the past decades. Particular emphasis was placed on the basic technology, specific parameters and interpretation, accuracy and reproducibility, field of clinical applications. Open questions were extensively discussed, limits of each technique clearly postulated. and a consensus statement put together for each of the technique involved. It encompassed techniques like color Doppler imaging, laser Doppler flowmetry (continuous as well as scanning LDF), laser Doppler velocimetry, Retinal Vessel Analyzer, combination of the vessel diameter measurement and the LDV, laser interferometry of the fundus pulsations amplitude, retinal oxymetry, measurements of the pulsatile component of the blood flow, blue field entoptic method and the newest - Doppler OCT. Conclusion There is no overwhelming measuring technique able to cover all the aspects of the research and the daily clinical routine. Various parameters and various vascular beds are involved, which makes the interpretation of the obtained results strenuous. Of particular importance is the capability of OBF measuring techniques to capture one dynamic feature of ocular circulation - its ability to regulate and to response to various challenges. It is widely believed that not the constantly reduced blood flow, but rather the lack of regulation thereof, leads to prevalent ocular diseases. [source]


Ocular perfusion and age-related macular degeneration

ACTA OPHTHALMOLOGICA, Issue 2 2001
Thomas A. Ciulla
ABSTRACT. Purpose: To review the role of ocular perfusion in the pathophysiology of age-related macular degeneration (AMD), the leading cause of irreversible blindness in the industrialized world. Methods: Medline search of the literature published in English or with English abstracts from 1966 to 2000 was performed using various combinations of relevant key words. Results: Vascular defects have been identified in both nonexudative and exudative AMD patients using fluorescein angiographic methods, laser Doppler flowmetry, indocyanine green angiography, and color Doppler imaging. Conclusion: Although these studies lend some support to the vascular pathogenesis of AMD, it is not possible to determine if the choroidal perfusion abnormalities play a causative role in nonexudative AMD, if they are simply an association with another primary alteration, such as a primary RPE defect or a genetic defect at the photoreceptor level, or if they are more strongly associated with one particular form of this heterogeneous disease. Further study is warranted. [source]


Ophthalmic artery blood flow velocity changes in diabetic patients as a manifestation of macroangiopathy

ACTA OPHTHALMOLOGICA, Issue 2 2000
Masanori Ino-ue
ABSTRACT. Purpose: The hemodynamic characteristics of ophthalmic artery (OA) blood flow velocity in diabetic patients with ocular involvement were evaluated. Methods: Changes in OA blood flow of eyes with background diabetic retinopathy (BDR), proliferative retinopathy (PDR) and ocular ischemic syndrome (OIS) were ananalyzed by Color Doppler imaging. Results: Patients with BDR and PDR had significantly lower diastolic and mean blood flow velocities and higher pulsatility indices compared to controls. Diabetic patients with OIS had significantly lower systolic, diastolic and mean anterograde OA blood flow velocities than the controls. Pulsatility indices were higher in anterograde OA blood flow measurements compared to controls. Systolic blood flow velocities in rubeotic eyes with OIS were significantly lower than in rubeotic eyes with PDR. Conclusion: OA blood flow measurements by color doppler imaging may detect macroangiopathies in diabetic patients as manifested by carotid atheromas and arterio- and arterosclerosis of the OA and its branches. [source]