B. Guias

Centre Hospitalier Privé Saint-Grégoire, Sant-Gregor, Brittany, France

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Publications (40)46.85 Total impact

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    ABSTRACT: Background. The assessment of clinical probability represents an important step in the diagnostic strategy of patients with suspected deep vein thrombosis. The recently derived "LEFt" clinical prediction rule for pregnant women combines three variables: symptoms in the left leg ("L"), calf circumference difference ≥ 2 centimeters ("E" for edema) and first trimester presentation ("Ft"), but is lacking an external validation. Design and Methods. The LEFt rule was computed among pregnant women with suspected deep vein thrombosis who were included in a multicentre prospective diagnostic management outcome study. We calculated the proportion of women and the prevalence of deep vein thrombosis in each probability group, along with the diagnostic performances of the LEFt rule. Results. All variables needed to compute the rule could be retrieved in 157 out of the 167 pregnant women with suspected deep vein thrombosis. The prevalence of confirmed deep vein thrombosis was 13/157 (8.3%). The "LEFt" rule was negative in 46 (29%) women. A deep vein thrombosis was diagnosed in 13/111 (11.7%, 95% CI: 8.3 to 20.9%) of women with at least one of the "LEFt" criteria, as compared with 0/46 (0.0%, 95% CI:0.0 to 7.9%) of women with none of the "LEFt" criteria. Conclusions. These results suggest that a negative "LEFt" rule accurately identifies pregnant women in whom the proportion of confirmed deep vein thrombosis appears to be very low. The rule should not be used as stand-alone test for excluding DVT during pregnancy but might rather be implemented in a diagnostic strategy in association with Ddimer measurement and compression ultrasonography.
    Haematologica 10/2012; · 5.94 Impact Factor
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    ABSTRACT: Historique Le syndrome du marteau thénarien est une affection très rare qui peut mimer des maladies rhumatologiques comme le syndrome du canal carpien, le phénomène de Raynaud voire une synovite du poignet ou de la main. Objectif Décrire la présentation échographique du syndrome du marteau thénarien chez un patient caractéristique. Méthodes Une échographie en mode B et en doppler couleur pulsé de la main (appareil iU22 Philips) a été réalisée. Résultats En mode B, il s’agit d’une lésion vasculaire de l’artère radiale perdant ses caractéristiques habituelles et révélant un pseudo-anévrisme avec présence de la formation d’un kyste sacciforme émergeant directement de l’artère adjacente et présentant une paroi d’épaisseur irrégulière avec un flux sanguin turbulent dans la lumière. Le Doppler couleur a montré un flux sanguin dans une partie de la lumière, dont le reste était rempli d’un thrombus apparaissant comme un tissu échogène. Conclusion L’échographie est une aide diagnostique non invasive du syndrome du marteau thénarien. L’angiographie est facultative chez les patients dont les résultats de Doppler couleur sont typiques.
    Revue Du Rhumatisme - REV RHUM. 01/2011; 78(2):184-186.
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    ABSTRACT: Thenar hammer syndrome is a very rare condition that mimics rheumatic diseases such as carpal syndrome tunnel, Raynaud's phenomenon, and hand synovitis. To describe the sonographic presentation of thenar hammer syndrome in a typical patient. Grey-scale sonography and colour Doppler imaging of the hands with an iU22 scanner (Philips) were performed. In B mode, the lesion was seen as a large, rounded, heterogeneous area combining hypoechoic and echogenic components. Pseudoaneurysm was diagnosed based on presence of a cystic saccular formation arising directly from the adjacent artery and exhibiting an irregular thick wall with turbulent blood flow in the lumen. Colour Doppler showed blood flow in part of the lumen, the rest of which was filled with a thrombus seen as echogenic tissue. Sonography can help to diagnose thenar hammer syndrome. Angiography may be unnecessary in patients with normal colour Doppler findings.
    Joint, bone, spine: revue du rhumatisme 10/2010; 78(2):212-4. · 2.25 Impact Factor
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    ABSTRACT: Venous thrombosis (VT) volume assessment, by verifying its risk of progression when anticoagulant or thrombolytic therapies are prescribed, is often necessary to screen life-threatening complications. Commonly, VT volume estimation is done by manual delineation of few contours in the ultrasound (US) image sequence, assuming that the VT has a regular shape and constant radius, thus producing significant errors. This paper presents and evaluates a comprehensive functional approach based on the combination of robust anisotropic diffusion and deformable contours to calculate VT volume in a more accurate manner when applied to freehand 2-D US image sequences. Robust anisotropic filtering reduces image speckle noise without generating incoherent edge discontinuities. Prior knowledge of the VT shape allows initializing the deformable contour, which is then guided by the noise-filtering outcome. Segmented contours are subsequently used to calculate VT volume. The proposed approach is integrated into a system prototype compatible with existing clinical US machines that additionally tracks the acquired images 3-D position and provides a dense Delaunay triangulation required for volume calculation. A predefined robust anisotropic diffusion and deformable contour parameter set enhances the system usability. Experimental results pertinence is assessed by comparison with manual and tetrahedron-based volume computations, using images acquired by two medical experts of eight plastic phantoms and eight in vitro VTs, whose independently measured volume is the reference ground truth. Results show a mean difference between 16 and 35 mm<sup>3</sup> for volumes that vary from 655 to 2826 mm<sup>3</sup>. Two in vivo VT volumes are also calculated to illustrate how this approach could be applied in clinical conditions when the real value is unknown. Comparative results for the two experts differ from 1.2% to 10.08% of the smallest estimated value when the image acquisition cadences are sim- ilar.
    IEEE Transactions on Information Technology in Biomedicine 04/2009; · 1.98 Impact Factor
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    ABSTRACT: Mondor's disease is spontaneously remitting benign superficial thrombophlebitis involving healthy veins. Fewer than 400 cases have been reported in the world literature. Typically, subcutaneous angiitis is observed on the upper anterolateral aspect of the chest wall. We report three cases in which Mondor's disease occurred after surgery for breast cancer in one patient, and had no apparent cause in two other patients. The relationship with breast cancer and risk factors suggests that routine mammography is advisable. For patients presenting idiopathic Mondor's disease, follow-up is of utmost importance.
    Journal des Maladies Vasculaires 01/2009; 34(1):54-60. · 0.24 Impact Factor
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    ABSTRACT: Mondor's disease is spontaneously remitting benign superficial thrombophlebitis involving healthy veins. Fewer than 400 cases have been reported in the world literature. Typically, subcutaneous angiitis is observed on the upper anterolateral aspect of the chest wall.We report three cases in which Mondor's disease occurred after surgery for breast cancer in one patient, and had no apparent cause in two other patients. The relationship with breast cancer and risk factors suggests that routine mammography is advisable. For patients presenting idiopathic Mondor's disease, follow-up is of utmost importance.
    Journal des Maladies Vasculaires 01/2009; 34(1):54-60. · 0.24 Impact Factor
  • Journal Des Maladies Vasculaires - J MAL VASCUL. 01/2008; 33.
  • Revue De Medecine Interne - REV MED INTERNE. 01/2008; 29.
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    ABSTRACT: Noninvasive objective tests are needed to diagnose primary Sjogren's syndrome (pSS) and to evaluate treatment responses. Ultrasound imaging of the salivary glands is rapid and noninvasive. Recent open-label studies suggested that anti-CD20 (rituximab) may be effective in pSS. The purpose of this study was to look for ultrasound evidence of the effects of rituximab in pSS. We compared 16 patients fulfilling the new American-European consensus group criteria for pSS to 9 controls, using B-mode ultrasound features (parenchymal homogeneity and gland size) and Doppler waveform analysis of the transverse facial artery of parotid glands. We compared the same parameters in the patients before and after 12 weeks of intravenous rituximab therapy. Compared to controls, untreated patients had significant abnormalities in salivary gland structure (p < 0.0001) and parotid size (2.05 +/- 0.33 cm versus 1.70 +/- 0.28 cm; p = 0.001). Doppler waveform analysis showed significant differences before, but not after, lemon stimulation between untreated patients and controls. After rituximab treatment, significant size reductions were noted in the parotids (2.05 +/- 0.3 cm at baseline and 1.86 +/- 0.27 cm at week 12; p = 0.002) and submandibular glands (2.02 +/- 0.54 cm at baseline and 1.66 +/- 0.34 cm at week 12; p = 0.001). Doppler resistive indices after lemon stimulation were significantly increased after rituximab treatment. Salivary gland measurements and blood inflow responses to salivary stimulation as assessed by ultrasound hold promise as objective noninvasive tools for evaluating rituximab effects in patients with pSS.
    Targets & therapy 10/2007; 1(3):311-9.
  • Journal Des Maladies Vasculaires - J MAL VASCUL. 01/2007; 32:49-51.
  • Journal Des Maladies Vasculaires - J MAL VASCUL. 01/2007; 32:63-64.
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    ABSTRACT: Foam echosclerotherapy by puncture - direct injection (EMPID) is a technique approved by the French Health Authorities for the management of varicose veins. It combines two principles: the injection of a sclerosing agent by echomonitored direct puncture and the use of this sclerosing agent as a foam. The procedure consists of four stages: targeting of the vein to sclerose and selection of the puncture site, venous puncture under echographic guiding, injection of the sclerosing product under complete echographic monitoring, and post-injection control, checking for the impact of the action and the distribution of the foam in the treated vein. First intention indications concern essentially isolated troncular reflux in lesser and great saphena veins and varicose recurrences. In second intention, EMPID is also an alternative to conventional varicose resection surgery. Emphasizing the principle of precaution, we underline the usefulness of a fine, extemporaneous, standardized and reproducible microfoam - high doses, in particular large volumes of foam, are unwarranted since it has been proven that small volumes are as effective. The recommended concentrations are directly linked to the maximal diameter of the saphena trunks targeted. The volume of foam to be injected must be determined on an individual basis and depends on the presence or not of post-injection spasm, the degree of venous filling and the endothelial impregnation of the treated varicosity (which can be easily monitored because of the spontaneous visualization of the foam producing a tracing effect on the ultrasound); it should not exceed 7.5 ml per session. Apart from the classical side effects due to the liquid form, the foam presents its own, very rare, side effects consisting of minor, constantly and spontaneously reversible, eye disorders. The foam is contraindicated for patients suffering from migraine due to higher incidence of such visual disorders. EMPID is an outpatient procedure for the treatment of varicosities which requires considerable operator skill. This technique cannot be proposed on a large scale without proper and specific training.
    Journal des Maladies Vasculaires 10/2006; 31(4 Pt 1):180-9. · 0.24 Impact Factor
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    ABSTRACT: We aimed at determining whether a negative single complete compression ultrasonography (CUS) of the lower limbs veins is a safe and accurate diagnostic method to rule out the diagnosis of deep venous thrombosis in pregnant and early postpartum women. Hospital-based retrospective study. The gynaecology and vascular ultrasound units of three general hospitals in western France. We identified from the hospitals databases all pregnant or up to three months postpartum women who underwent CUS for a suspicion of deep venous thrombosis between January 2002 and December 2004. Questionnaires were sent to all women with a negative CUS. Their medical records were also checked. We assessed the three-month thromboembolic risk and its 95% percent confidence interval in women left untreated on the basis of a negative single complete CUS of the lower limbs. During the study period, 162 pregnant or postpartum women underwent CUS for a suspicion of deep venous thrombosis. It was positive in 44 (27%). The 118 women who had a negative CUS were sent the questionnaire. Information about the three-month follow-up was found for 107 patients (91%). None of them experienced a thromboembolic event during follow-up: 0.0% (95% CI: 0.0-3.6). Single complete CUS of lower limbs veins appears to be a safe method to rule out the diagnosis of deep venous thrombosis in pregnant or early postpartum women. This has to be confirmed by a prospective management study with a formal follow-up.
    Thrombosis Research 02/2006; 118(6):691-7. · 3.13 Impact Factor
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    ABSTRACT: The authors sought to determine in a retrospective analysis whether carotid plaque soft TD on CT is associated with recent ischemic neurologic events. Among 141 patients (99 asymptomatic), 106 plaques with more than 50% stenosis were selected for density measurements. They found an odds ratio for neurologic events associated with a 10-point decrease in density of 1.54 (p = 0.002), showing an association between plaque density and neurologic events.
    Neurology 02/2006; 66(1):118-20. · 8.30 Impact Factor
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    ABSTRACT: Foam echosclerotherapy by puncture - direct injection (EMPID) is a technique approved by the French Health Authorities for the management of varicose veins. It combines two principles: the injection of a sclerosing agent by echomonitored direct puncture and the use of this sclerosing agent as a foam. The procedure consists of four stages: targeting of the vein to sclerose and selection of the puncture site, venous puncture under echographic guiding, injection of the sclerosing product under complete echographic monitoring, and post-injection control, checking for the impact of the action and the distribution of the foam in the treated vein. First intention indications concern essentially isolated troncular reflux in lesser and great saphena veins and varicose recurrences. In second intention, EMPID is also an alternative to conventional varicose resection surgery. Emphasizing the principle of precaution, we underline the usefulness of a fine, extemporaneous, standardized and reproducible microfoam — high doses, in particular large volumes of foam, are unwarranted since it has been proven that small volumes are as effective. The recommended concentrations are directly linked to the maximal diameter of the saphena trunks targeted. The volume of foam to be injected must be determined on an individual basis and depends on the presence or not of post-injection spasm, the degree of venous filling and the endothelial impregnation of the treated varicosity (which can be easily monitored because of the spontaneous visualization of the foam producing a tracing effect on the ultrasound); it should not exceed 7.5 ml per session. Apart from the classical side effects due to the liquid form, the foam presents its own, very rare, side effects consisting of minor, constantly and spontaneously reversible, eye disorders. The foam is contraindicated for patients suffering from migraine due to higher incidence of such visual disorders. EMPID is an outpatient procedure for the treatment of varicosities which requires considerable operator skill. This technique cannot be proposed on a large scale without proper and specific training. (J Mal Vasc 2006 ; 31 : 180-189).
    Journal Des Maladies Vasculaires - J MAL VASCUL. 01/2006; 31(4):180-189.
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    ABSTRACT: Venous thrombosis is a common pathology that creates serious public health problems. Thrombosis diagnosis, particularly the determination of their echogenicity and echostructure can be efficiently accomplished by a medical expert using ultrasound imaging. On the other hand, the predictive capability of artificial neural networks is very useful in medical applications and can support medical experts to take appropriate diagnosis decisions. Therefore, the proposed study intends to characterize by means of neural networks the thrombosis echogenicity and echostructure, using a predefined learning base that depends on the prior knowledge of physicians. We have studied six different methods to characterize the thrombosis images, along with the six corresponding neural networks. Obtained results show that the optimal feature vector size, the simplest neural network architecture, and the smallest error, are achieved by using the mean-variance approach or by the wavelet coefficients energies method
    Information and Communication Technologies, 2006. ICTTA '06. 2nd; 01/2006
  • Journal des Maladies Vasculaires 10/2005; 30(4 Pt 1):235-6. · 0.24 Impact Factor
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    ABSTRACT: Venous thrombosis screening exams use 2D ultrasound images, from which medical experts obtain a rough idea of the thrombosis aspect and infer an approximate volume. Such estimation is essential to follow up the thrombosis evolution. This paper proposes a method to calculate venous thrombosis volume from non-parallel 2D ultrasound images, taking advantage of a priori knowledge about the thrombosis shape. An interactive ellipse fitting contour segmentation extracts the 2D thrombosis contours. Then, a Delaunay triangulation is applied to the set of 2D segmented contours positioned in 3D, and the area that each contour defines, to obtain a global thrombosis 3D surface reconstruction, with a dense triangulation inside the contours. Volume is calculated from the obtained surface and contours triangulation, using a maximum unit normal component approach. Preliminary results obtained on 3 plastic phantoms and 3 in vitro venous thromboses, as well as one in vivo case are presented and discussed. An error rate of volume estimation inferior to 4,5% for the plastic phantoms, and 3,5% for the in vitro venous thromboses was obtained.
    Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 02/2005; 4:4002-5.
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    ABSTRACT: Drug addiction which entails cardiovascular risks unknown or misknown to physicians, currently involves an increasing number of miscellaneous drugs, existing in manifold forms. There appears to be no bounds on the way of intake. All territories of the body may be affected with more or less severity. In young people, the cardiac, coronary, cerebral and peripheral vascular systems are generally involved. Two illicit drugs, cannabis and cocaine, showing a permanent increase in misuse, prevail. This drug addiction comes along with intercurrent pathologies which have their own vascular toxicity, especially HIV infection. Moreover, the advent of new illicit substances emphasizes the complexity of the clinical presentations. These complex situations have a real social and medical impact. We are currently in a phase of permanently increasing risk of cardiovascular complications. The pathophysiological mechanisms involved are intertwined and complicated by the frequent association of polytoxicomania or by the effects excipients added to these drugs: direct vascular toxicity, angeitis, arterial and venous thrombosis. Arsenic, a common component of these drugs, is also found in cigarettes; arsenic toxicity mainly affects the lower limbs. Treatment of these complications is non-specific; the ideal solution being weaning which, unfortunately in this peculiar population of patients, may entail serious complications due to the misuse of substitution products.
    Journal des Maladies Vasculaires 01/2005; 29(5):243-8. · 0.24 Impact Factor
  • Lancet. 01/2005; 30(4):18-18.