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F Tranquart

Publications and source records attributed to F Tranquart.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Contrast-enhanced ultrasonography: renal applications].

Color Doppler US of the urinary tract is still facing a few limitations including, for B-mode imaging, the detection of small lesions, and, for color Doppler, the detection of low flow. Ultrasound contrast agents (USCA) improve these two limitations and allow the development of new functional applications for renal blood flow quantification. This improvement results from an increased acoustic response obtained from the microbubbles, as well as from the development of pulse sequencing and signal processing that led to the concept of specific ultrasound sequences. Most of the clinical indications of contrast-enhanced ultrasonography remain to be validated with the improved detection of the non linear response. USCA improve the detection of abnormal micro and macrovascular disorders of the kidney, particularly for the detection and the characterization of renal artery stenosis, as well as for the visualization of renal infarction. This technique showed potentials for the study of renal masses, especially atypical cystic lesions. Among the remaining indications, the detection of reflux and testicular torsion are the most promising.

Adult↗
PubMed2003

[Sonographic diagnosis of ovarian tumors: pre-operative Doppler evaluation].

Pelvic sonography is the gold standard for diagnosis of ovarian masses. Only 2% of adnexal masses or malignant or bordeline tumors. Does Doppler US improve the diagnostic accuracy of sonography? The purpose of this article is to review current data and identify what areas still require further evaluation with regards to Doppler characterization of adnexal masses. It has been shown that Doppler evaluation of the ovary and cyst or tumor improves the diagnostic accuracy of US to differentiate between benign and malignant lesions. Hemodynamic data collected from pulsed Doppler imaging and Doppler energy vascular mapping have been shown to improve the characterization of malignant lesions. These data improve the accuracy of B-mode US combined with clinical evaluation and CA125 measurement. Nonetheless, the sensitivity and specificity values are between 85-90%, with few missed malignancies, but several false positive results. Useful Doppler data include the resistive index and the central intratumoral location of vascular flow. The use of 3D US with computer post-processing as well as sonographic contrast agents could provide additional information, but these techniques have not yet been validated. All suspicious adnexal lesions should be evaluated by an experienced sonographer and include discriminatory parameters to distinguish between benign and malignant lesions.

Female↗
PubMed2002

Uterine necrosis after arterial embolization for postpartum hemorrhage.

BACKGROUND: Selective embolization is an effective and reputedly safe method of managing pregnancy-related bleeding. However, we report an ischemic uterine necrosis after arterial embolization. CASE: The patient had heavy postpartum bleeding treated by embolization of the uterine arteries using polyvinyl alcohol particles (diameter 150-250 and 300-600 microm) and gelatin sponge pledgets. Her postoperative recovery was complicated by menorrhagia and pelvic pain. Because of the persistent menorrhagia and risk of infection, a hysterectomy was performed. Histopathology of the hysterectomy specimen revealed massive ischemic myometrial necrosis. CONCLUSION: This complication is most likely related to the small size of the particles used. In the management of postpartum bleeding by arterial embolization, the material of choice is gelatin sponge pledgets, and the use of small particles should be avoided.

Adult↗
PubMed2002

Prospective sonographic assessment of uterine artery embolization for the treatment of fibroids.

OBJECTIVES: To evaluate sonographic features following uterine artery embolization and to assess using ultrasound the efficacy of embolization as the primary treatment of fibroids. DESIGN: Fifty-eight women (mean age, 44.5 years; range, 33-65 years) suffering from symptoms due to fibroids (menometrorrhagia, bulk-related symptoms, pelvic pain) were followed-up after uterine artery embolization by ultrasound examination at 3 months, 6 months, 1 year and 2 years with assessment of volume and vascularization of fibroids as well as uterine vascularization. RESULTS: Fifty-eight patients were examined at 3 months, 46 at 6 months, 36 at 1 year and 19 at 2 years. Most patients were improved or free of symptoms at 3 months (90%), 6 months (92%) and 1 year (87%) and all monitored patients were free of symptoms at 2 years. Clinical failure of treatment occurred in only two cases (3%). Progressive significant reduction in fibroid size with reference to the baseline was demonstrated during follow-up from 3 months (-29%) to 24 months (-86%). Absence of intrafibroid vessels was observed in all except three cases as early as 3 months, whereas perifibroid vessels persisted in 21 cases. No changes in uterine vascularization or uterine artery resistance were noted. CONCLUSIONS: Uterine artery embolization is a valuable endovascular method for the treatment of fibroids, resulting in marked reduction in fibroid size and disappearance of intrafibroid vessels without reduction in uterine vascularization which is well depicted by sonography.

Adult↗
PubMed2002

Follow up by colour Doppler imaging of 102 patients with retinal vein occlusion over 1 year.

BACKGROUND/AIM: Retinal vein occlusion (RVO) is one of the most frequent ocular vascular diseases and leads to severe vision impairment. Colour Doppler imaging (CDI) is the first method which allows distinct evaluation of arterial and venous velocities in RVO. CDI is valuable for diagnosis of RVO and shows the effects of isovolaemic haemodilution. Patients with RVO were monitored by CDI for 1 year in order to clarify venous and arterial involvement in the pathogenesis of this disease. METHODS: Patients with RVO were monitored prospectively for 1 year with clinical examinations, fluorescein angiography, and CDI every 3 months. 102 adults referred for RVO for less than 2 months were enrolled. Unaffected eyes were used as control. The maximum systolic and diastolic flow velocities and the resistance index (RI) were measured in the central retinal artery (CRA) and the maximum and minimum blood flow velocities in the central retinal vein (CRV). RESULTS: During the year of observation, branch retinal vein occlusion (BRVO), ischaemic central retinal vein occlusion (CRVO), and non-ischaemic CRVO had a distinct pattern of venous velocity changes. BRVO had a similar profile to that observed in controls. Venous velocities were continuously lower in central forms, with the lowest values in ischaemic occlusion. In contrast, a brief decrease in arterial diastolic velocity was observed in ischaemic CRVO at presentation, correlated with arteriovenous passage time on fluorescein angiography, but with rapid normalisation. CONCLUSIONS: CDI findings were correlated with the type of RVO at all times during follow up. CDI showed persistent impairment of central venous velocity in CRVO whereas there was a fast initial values recovery of the arterial velocity. These results using CDI show strong evidence of a primary venous mechanism in RVO.

Adult↗
PubMed2001

D2 receptor imaging in neonates using I-123 iodobenzamide brain SPECT.

PURPOSE: Hypoxic-ischemic injury induces early changes in cerebral energy that later lead to the presence and extension of brain damage and subsequently to severe neurodevelopmental impairments such as the dyskinetic form of cerebral palsy, which is associated with damage to the striatum. The purpose of the current study was to evaluate the viability of D2 receptors in the perinatal period using I-123 iodobenzamide brain SPECT and to correlate this with early neurologic status. METHODS: After obtaining informed parental consent, 12 full-term neonates with hypoxic-ischemic events were included. I-123 iodobenzamide brain SPECT was performed 1 week after birth, corresponding to a gestational age of 39.2+/-1.7 weeks. Images were acquired using a brain-dedicated gamma camera 1 hour after intravenous injection of 30 MBq (0.8 mCi) I-123 iodobenzamide. Magnetic resonance images (T2 weighted sequence: repetition time/echo time: 2,000/30 to 150) of the brains of the same neonates were acquired on the same day. RESULTS: The right and left striatum:cerebellum activity ratios were between 1.28 and 2.25, with the greatest concentration of I-123 iodobenzamide occurring in the striatum area. A tendency of the striatum:cerebellum ratio to decrease was observed as the severity of the perinatal hypoxic-ischemic event increased despite striatal hypersignal on magnetic resonance imaging in only two neonates. CONCLUSIONS: This study, which confirms that I-123 iodobenzamide could be used in the neonatal period, shows the biochemical maturation of D2 receptors as early as 1 week after birth and also suggests the deleterious effect of perinatal hypoxic-ischemic events on D2 receptors.

Brain↗
PubMed2001

Quantitative analysis of striatal dopamine D2 receptors with 123 I-iodolisuride SPECT in degenerative extrapyramidal diseases.

123I-Iodolisuride has high specific affinity for binding on dopamine D2 receptors in the striatum and has been used in a few single photon emission computed tomography (SPECT) studies of extrapyramidal disorders. The diagnosis of Parkinson's disease (PD) is very difficult in the first 5 years of evolution, with 15-25% false positive diagnoses. The aim of this study was therefore to determine the value of iodolisuride SPECT in discriminating Parkinson's from the most frequent Parkinson-plus syndromes (PPS). Seventeen patients with an extrapyramidal syndrome had a SPECT examination 1 h after injection of 180-185 MBq of 123I-iodolisuride. They were followed under dopaminergic treatment for at least 2 years. After 2 years, they were separated in two groups according to specific clinical criteria and sensitivity to dopaminergic treatment: nine patients had PD (age = 59.8+/-8.8 years; Hoehn and Yahr = 1.8+/-0.7; evolution = 4.3+/-3 years) and eight had PPS (age = 71.6+/-7.3 years; Hoehn and Yahr = 2.9+/-2.0; evolution = 4.1+/-1.5 years). The binding potential of iodolisuride in the striatum was assessed by considering the striatum (S)/occipital lobe (O) ratio at the pseudo-equilibrium 1 h after injection. The S/O ratio was statistically different between PD and PPS (1.97+/-0.3 vs. 1.65+/-0.2 (P<0.02)). Iodolisuride SPECT could differentiate both groups with a sensitivity of 88.8% and a specificity of 75%. Iodolisuride is a good specific D2 receptor ligand for SPECT and complements specific clinical criteria for the diagnosis of Parkinson's disease and differentiation between different extrapyramidal disorders.

Aged↗
PubMed2001

Accuracy of color-Doppler in the quantification of proximal vertebral artery stenoses.

BACKGROUND: Vertebrobasilar (VB) strokes appear to have the same causes as carotid strokes. Obstructive lesions of proximal vertebral arteries probably occur in about 30% of stroke patients. PURPOSE: Our aim was to assess the validity of color Doppler sonography compared to selective intra-arterial angiography in the quantification of proximal vertebral artery stenoses. MATERIALS AND METHODS: A prospective blind study of 316 vertebral arteries was undertaken between 1996 and 1998. One hundred and fifty-eight patients with cerebrovascular disorders without cerebral hemorrhage were studied consecutively by frequency or amplitude color Doppler flow imaging and intra-arterial angiography. The lesions were quantified by morphological and hemodynamic criteria and classified into 6 groups: 0% 207 arteries; 1-29% 32 arteries; 30-49% 29 arteries; 50-69% 13 arteries; 70-99% 23 arteries; 100% 12 arteries. RESULTS: Ten of the 12 occlusions were identified, the 2 false-negatives were due to 2 revascularized vessels. Moderate stenoses (<50%) were differentiated from tight stenoses (>50%) using hemodynamic criteria. The majority of false-negative stenoses (38) in the different groups were related to intrathoracic or very deep origin of the artery, anechogenic stenosis or a tortuous vessel. Stenoses greater than 70% were diagnosed in 71% of cases with a specificity of 99%. The kappa value was 0.80. CONCLUSION: Duplex sonography should be proposed first in VB attacks or stroke to detect and quantify vertebral artery stenoses for surgery and angioplasty.

Arterial Occlusive Diseases↗
PubMed2001

[Incidental detection of a rare liver tumor: angiomyolipoma].

We report the case of a woman who presented a single liver lesion with no evidence of specific findings at Doppler US, CT, nuclear studies and MRI to suggest angiomyolipoma. The final diagnosis was confirmed at anatomopathology and immunohistochemistry which demonstrated positive anti-HMB 45 aspect.

Angiomyolipoma↗
PubMed2001

[Quantification of hepatic arterial and portal venous flow using ultrasound contrast agents for early detection of liver metastases of colorectal cancers].

PURPOSE: To quantify liver blood flow using US contrast agents and to evaluate arterial and portal changes in control patients and patients with liver metastases. MATERIALS AND METHODS: Twenty eight patients were included in this study, 8 controls (M0) and 20 patients with liver metastases from colon carcinoma (M+). Hepatic blood flow from hepatic artery and portal vein were determined using quantification of enhancement after contrast injection using Power Doppler US. The ratio of enhancement rise from artery and vein allows calculation of Contrast Enhanced Doppler Perfusion Index (CEDPI) as previously described for Doppler Perfusion Index (DPI). RESULTS: A significant difference was noted for CEDPI between controls (0.49 +/- 0.07) and liver with metastases (0.70 +/- 0.12). CONCLUSION: This functional method of evaluation of liver blood flow was easy to perform, and would be valuable for early detection of overt micro-metastases before anatomical changes observed by conventional imaging. This is helpful for accurate staging of colon carcinoma.

Adult↗
PubMed2000

Initial color Doppler findings in retinal vein occlusion.

PURPOSE: We assessed early hemodynamic characteristics of various types of retinal vein occlusion using color Doppler imaging and spectral analysis. METHODS: We measured the maximum systolic and diastolic blood flow velocities and the resistance index (RI) in the central retinal artery and the maximum and minimum blood flow velocities in the central retinal vein of affected eyes and contralateral unaffected eyes in 102 adults (63 men and 39 women; mean age, 61 +/- 14.6 years) who presented with retinal vein occlusion. Sixty-three control subjects (27 men and 36 women; mean age, 50 +/- 22.1 years) were also investigated. RESULTS: No significant differences in hemodynamic characteristics were found between the control subjects' eyes and the patients' unaffected eyes. In the 18 cases of ischemic central retinal vein occlusion, the mean diastolic arterial flow velocity (p = 0.005) and venous flow velocity (p < 0.04) were lower and the mean RI was higher (p = 0. 0002) in the affected eyes than in the unaffected contralateral eyes. In the 51 cases of nonischemic central retinal vein occlusion, the mean diastolic arterial flow velocity (p < 0.0001) and venous flow velocity (p < 0.0001) also were lower and the mean RI (p < 0.0001) was higher in the affected eyes than in the unaffected contralateral eyes. These variables were different in the ischemic versus nonischemic types of central retinal vein occlusion. In the 33 cases of branch retinal vein occlusion, no significant differences were observed in arterial or venous blood flow velocities in the affected versus unaffected eyes. The mean RI in the affected eyes was significantly higher (p = 0.009) in patients with central versus branch retinal vein occlusion. CONCLUSIONS: These results suggest that previous arterial disorders were not involved in the pathogenesis of central retinal vein occlusion in these patients. The findings also support the value of Doppler imaging and spectral analysis in the diagnosis and evaluation of retinal vein occlusion and confirm the involvement of arterial flow in venous occlusion.

Adult↗
PubMed2000

The DopFet system: a new ultrasonic Doppler system for monitoring and characterization of fetal movement.

To enable the investigation of fetal movement in a manner similar to fetal heart rate (FHR) monitoring we have developed an apparatus (the DopFet system) that consists of a pair of miniature sensors, a 2-MHz continuous-wave directional Doppler electronic module and a laptop personal computer. One of the sensors is aimed at the fetal limbs and the other at the thorax to detect heart and upper body movements. The signals are analyzed, presented in real-time and postprocessed by software developed by us. The postprocessing software computes a number of parameters (the DopFet parameters) describing fetal movement. These parameters can be divided into two categories: parameters that describe the quantity of fetal movement (i.e., number of movements) and parameters that describe qualitative aspects of fetal movement (i.e., average movement duration). Future studies using the DopFet system will be aimed at discovering which of these parameters or combination of parameters is the best indicator of fetal well-being. We present an example of a 0.5 h recording and the results of testing on 23 volunteer mothers. These results show good sensitivity of the system compared to real-time ultrasound (US). The system detects 96% of rolling movements, 100% of flexion movements and 97% of leg movements.

Female↗
PubMed2000

Ultrasonic assessment of variations in thickness of subcutaneous fat during the normal menstrual cycle.

OBJECTIVE: To verify the occurrence of natural variations in thigh and abdominal subcutaneous fat thickness related to the phases of the menstrual cycle, to assess the value of ultrasonography as a reliable method for monitoring subcutaneous fat thickness changes and to evaluate their amplitudes. METHODS: This study included 10 women (19-39 years) who menstruated regularly. None had used oral contraceptives or slimming products during the 3 months prior to the study. At cycle day 2 (CD2), CD6, CD14, CD22, CD27 and CD30 days (CD0: beginning of menstruation), the subjects were submitted to: (1) measurement of weight and thigh perimeters, (2) measurements of thigh and abdomen subcutaneous fatty tissue thickness on B-mode images acquired at 10 MHz. A protocol was designed to guarantee a reproducible repositioning during the whole time course of the study and ultrasound examinations (US) were always performed by the same trained person to avoid inter-examiner variability. RESULTS: Subcutaneous fat thicknesses decreased during the first half of the cycle and reached their lowest values at day 22 (-2.0% for the thighs; -3.3% for the abdominal region). Both thigh and abdomen subcutaneous fat reached their maximum thicknesses during menstruation with respective increases of +2.2 and +4.0%. The observed cyclic amplitude variations in the subcutaneous adipose tissue thickness accounted for 7.3% for the abdominal region and 4.1% for the thighs. CONCLUSION: Variations in adipose tissue thickness during the menstrual cycle could be quantified and monitored by US. The thickness of the thigh and abdominal hypodermis was more important during menstruation and decreased in mid-cycle with a minimum occurring 1 week after ovulation.

Abdominal Muscles↗
PubMed2000

Localization of the ventricular preexcitation site in Wolff-Parkinson-White syndrome with Doppler tissue imaging.

PURPOSE: The objective of this study was to evaluate the ability of Doppler tissue imaging (DTI) to localize the ventricular emergence site of accessory atrioventricular pathways (Wolff-Parkinson-White syndrome). METHODS: Thirty-three patients were studied prospectively by Doppler tissue imaging (128XP and Sequoia 256 echocardiographic systems; Acuson, Mountain View, Calif) before investigation of Wolff-Parkinson-White syndrome and after radiofrequency ablation of the accessory pathways. The normal appearance of the ventricular contractions was defined in a group of 10 control subjects. The preexcitation zone was determined as a zone of maximum acceleration in "DTI acceleration mode" or as a coded contraction zone in "DTI velocity mode," at the time of the delta wave or before the onset of the QRS complex. RESULTS: The earliest ventricular activation site was correctly localized for 12 of the 15 left-sided pathways (8 anterior or anterolateral, 2 lateral or posterolateral, 2 inferior). When wall motion abnormalities were detected in the left ventricle by DTI, the left-sided localization was confirmed by electrophysiologic exploration. For the right-sided pathways, the localization was correct in only 4 of 11 cases (3 posteroseptal and 1 anterolateral). After effective ablation in all patients, the abnormalities corresponding to the electrophysiologic data disappeared totally in only 11 of 16 patients. CONCLUSION: In the presence of Wolff-Parkinson-White syndrome, DTI localizes contraction abnormalities associated with early activation of a part of the ventricle. However, the interpretation of the images remains difficult because the normal coding of the contraction of the ventricular walls depends on the incidence for which they are investigated. This noninvasive examination seems to be an effective tool for localizing the left-sided accessory pathways of the left ventricle, in particular in the anterior, anterolateral, or inferior walls.

Adult↗
PubMed2000

Identification of microemboli during haemodialysis using Doppler ultrasound.

BACKGROUND: Doppler ultrasound methods were used during haemodialysis sessions for the detection of microemboli and determination of their origin. METHODS: A 2-MHz ultrasound probe (Multidop X(4) DWL((TM))) was used to assess the number of microembolic signals (MES) in the subclavian vein downstream from the arteriovenous fistula before the dialysis session and over two periods of 15 min at the beginning and end of haemodialysis sessions in 25 patients without previous cardiovascular disease. A similar probe was used during in vitro studies to detect MES at different sites in the dialysis machine (before and downstream from the blood pump, and before and downstream from the air trap). RESULTS: No MES were detected during in vivo studies before haemodialysis sessions. MES were registered in all patients (100%) at the beginning and end of the haemodialysis procedure at an average of 12.7+/-9 and 16. 7+/-11.5 signals/min respectively. The average intensity of MES was 19.2+/-5.0 dB and 19.4+/-3.9 dB respectively. No MES were detected on the arterial line during in vitro studies. In contrast, 19+/-6 MES/min were detected after the blood pump, 13+/-4.2 before the air trap, and 16.5+/-5.5 thereafter. CONCLUSIONS: In all patients, MES were recorded during haemodialysis sessions in the drainage vein from arteriovenous fistulae. The results of in vitro studies indicate that MES are formed by the blood pump of the haemodialysis machine. The intensity of the MES suggests that they correspond to synthetic particles or microbubbles, which are not detected by the air trap. The final destination of these microbubbles will be assessed in further studies.

Adult↗
PubMed2000

Uterine artery embolization in the primary treatment of uterine leiomyomas: technical features and prospective follow-up with clinical and sonographic examinations in 58 patients.

OBJECTIVE: The purpose of this study was to analyze the technical features of uterine artery embolization and to evaluate the effectiveness of this method as the primary treatment of uterine leiomyomas in a series of 58 patients monitored by clinical and sonographic examinations. SUBJECTS AND METHODS: Fifty-eight women (age range, 33-65 years; mean age, 44.5 years) with symptoms caused by uterine leiomyomas (abnormal bleeding, bulk-related symptoms, pelvic pain) were included in this prospective study. We performed embolization with a single catheter using the single-femoral artery approach, injection of particles (150-250 mm), and an absorbable gelatin sponge. Postprocedural pain was assessed using a visual analog scale. Systematic follow-up included clinical and sonographic examinations at 3 months for 58 patients, at 6 months for 46 patients, at 1 year for 27 patients, and at 2 years for seven patients. RESULTS: Embolization was performed without problems in 84% of the patients. Post-procedural pain control was excellent in 90% of the patients. In most patients, symptoms were improved or had resolved at 3 months (90%), 6 months (92%), and 1 year (93%), and all patients were symptom-free at 2 years. Clinical failure of treatment occurred in only two patients (3%). Progressive reduction in leiomyoma size was revealed during sonographic follow-up, and new leiomyomas were seen in one patient at 2 years. CONCLUSION: Uterine artery embolization is an endovascular method for the treatment of uterine leiomyomas that is clinically effective in most patients and that induces a progressive reduction in the size of the largest leiomyomas.

Adult↗
PubMed2000

[Doppler ultrasonography of carotid atheromatous lesions].

Carotid stenosis is the most frequently factor involved in stroke. The diagnosis of these lesions in routinely based on ultrasonic examination which allows to detect the carotid stenoses which were essentially atheromatous. B-mode evaluates the fine echostructure of plaques and Doppler helps to quantify the degree of stenosis using direct and indirect hemodynamic criteria. Echography with the help of color Doppler imaging identifies the site of stenosis in order to determine the degree of stenosis as a percentage of normal carotid area. Moreover echography is an essential method to appreciate the surface as well as the echostructure of the carotid lesion which have to be taking into account for a well-adapted therapy. The maximal velocities determined at the tight site of the lesion, the spectral changes downstream the stenosis and the hemodynamic changes observed upstream and downsteam of the carotid stenosis allow a precise quantification of this stenosis. The information obtained using sonographic methods (including 2 direct hemodynamic criteria, 2 indirect hemodynamic criteria and, if possible, a B-mode assessment of the area) are essential to appreciate the neurological risk in these patients.

Carotid Artery Diseases↗