PubMed Health⌕ Search

Biomedical subjects

J P Laroche

Publications and source records attributed to J P Laroche.

At least 19 recordsLinked to original sources
PubMed2006

[Diagnosis and treatment of thromboembolic events in pediatrics].

Thromboembolic events are an increasingly commonly recognized secondary complications in children treated for serious, life-threatening primary diseases. Nevertheless the incidence of venous thromboembolic disease remains 100 times less frequent in hospitalized children than hospitalized adults, as recent data suggest an incidence of 5,3/10.000 pediatric patients compared to an incidence of 2,5-5/100 in adult patients. Diseases usually associated with thromboembolic events in children are neoplasia, autoimmune or cardiac malformative disease. Contrarily to what is observed in the adult, the majority of deep vein thrombosis events occur at the upper limbs veins, usually at the place where devices for venous access like port-a-cath or central venous lines are inserted. Because of the relatively low incidence of venous thromboembolic events in children, the diagnostic approach used are largely extrapolated from guidelines obtained from adult studies. However, the diagnostic performances of some diagnostic tools like Doppler-Ultrasound are probably diminished in children. Moreover, the concept of developmental hemostasis, which stresses the point that the hemostatic system in children is quite different from the adult one, is widely accepted and clearly suggests that the diagnostic and therapeutic approach in pediatric patients may not be simply extrapolated from data obtained in adult studies. From a more practical point of view, the fact that the hemostatic system in children is a dynamic and evolving system, renders the therapeutic approach quite complex. In particular, doses of anticoagulants vary markedly across the pediatric age. The absence of adapted formulations of commonly used anticoagulants, for example the absence of liquid formulations of anti-vitamin K drugs, further complicates the administration and the correct monitoring of anticoagulation in children, and may diminish observance in adolescent patients. Even though the concept that "children are not little adults" is nowadays widely accepted, there is an urgent need for prospective studies to better assess the modalities of diagnosis and treatment of venous thromboembolic disease in this particular population.

Adult↗
PubMed2005

[Optimizing history taking for evaluating the risk of venous thromboembolism: the OPTIMEV study].

UNLABELLED: Venous thromboembolism (VTE) is a frequent disease and remains a major cause of mortality and morbidity among our patients. During the 20 past years, clinical description, diagnostic tools, and treatment have changed dramatically. Most published data describing risk factors for VTE no longer apply to the patients seen in daily practice. We present here the rationale, aims, and methodology of the OPTIMEV Study (OPTimisation de l'Interrogatoire pour la Maladie thromboEmbolique Veineuse). RATIONALE: Risk factors for VTE are numerous, complex and interactions between them and their clinical importance is difficult to measure (table I). For example, odds ratios for VTE recurrence vary greatly across longitudinal studies. We searched the National Library of Medecine (PubMed) and the Amedeo website using the following keywords: "venous thromboembolism", "pulmonary embolism", "deep vein thrombosis", "risk factors". We selected 84 relevant articles published between 1972 and 2005. Based on this literature analysis, we identified the following major risk factors: VTE recurrence, surgery, cancer, immobilization, age, biological factors. For these factors, data are lacking and some questions are proposed. OBJECTIVES: The broad objective of the study is to better evaluate clinical risk factors that fit today's practice against VTE. Specific aims are: 1) to determine whether risk factors are different between proximal and distal deep vein thrombosis (DVT); 2) to develop and prospectively validate a new prediction rule for outpatients. The primary hypothesis is that careful assessment of VTE recurrence, adequate surgical thromboprophylaxis, cancer staging, and varicose vein stratification according to the CEAP classification, is mandatory for accurate evaluation of thromboembolic disease risk. METHODS: We conducted a multicenter, prospective, cohort study of 10000 patients. Enrollees are inpatients and outpatients presenting with a clinical suspicion of VTE in Emergency Departments and outpatient clinics in France. 4173 patients have been enrolled at this time (Figure 2). All eligible patients are enrolled during a selected period of time through different seasons. Data are collected by physicians in charge of the patients using an electronic case recording form. Collected data include baseline characteristics, risk factors, results of diagnostic investigations. Outcome measures obtained through telephone interview at 3 and 12 months include cancer diagnosis, VTE recurrence, haemorrhagic events, treatments, death. Univariate and multivariate analysis will be performed using multilevel logistic regression. The study organization is performed by the Centre d'Investigation Clinique de Grenoble and is sponsored by the French Society of Vascular Medicine. First results, to be published in 2006, will allow development of new prediction rules for VTE diagnosis.

Age Factors↗
PubMed2004

[Treatment of postcatheterization femoral false aneurysms].

The incidence of iatrogenic femoral false aneurysms has risen dramatically in recent years and is estimated at 0,5% for diagnostic procedures and may rise to 9% or more for therapeutic procedures. This increased incidence is related to the increased number of arterial punctures performed for diagnostic or therapeutic purposes and their major complexity and duration. Risk factors for the development of iatrogenic false aneurysms include operator inexperience, age greater than 60, female gender, catheter size greater than 8F and concurrent anticoagulation. Prevention of false aneurysms is based upon an atraumatic arterial puncture, good compression therapy after sheath removal and use of percutaneous arterial closure devices. Contrarily to the arterial lesions following severe injuries, the natural course of false aneurysms is quite benign with spontaneous occlusion in the majority of cases. Therefore, a mandatory surgical approach is no longer advocated and alternative therapeutic options have been proposed. These include sonographic surveillance, compression ultrasonography, percutaneous thrombin or coil embolization. Surgery is still clearly indicated in presence of local nervous or venous compression, associated homolateral lower limb ischemia, great size of the aneurysm, and unsuccessful non-invasive treatment. Sonographic surveillance has shown to be safe in hospitalized or ambulatory patients. However, fear of aneurysm rupture and cost of repeated ultrasonographic exams preclude widespread utilisation. Compression ultrasonography is safe and effectiveness varies between 70 and 100%, according to studies. Compression ultrasonography may be painful, has often to be associated with mild analgesia, is time consuming and less effective in presence of concurrent anticoagulation. Thrombin injection seems particularly effective, is painless and has a limited rate of complications in expert hands. Severe anaphylactic reactions and severe coagulopathy in reexposed patients have been described and represent clear contra-indications to thrombin injection. Coil embolization of the false aneurysm is as effective as thrombin injection and is reported in a limited number of patients. There is no formal consensus about treatment of the vast majority of non-surgical false aneurysms. In an absence of stringent indication to surgical approach, compression ultrasonography may be used first as it is widely available, and does not require highly specialized skills. Compression therapy should be done after a transient interruption of anticoagulant treatment, if allowed by clinical context. If compression therapy fails, percutaneous injection of thrombin or coil embolization are effective and associated with a low complication rate. However, these techniques are less widely available and necessitate an experienced operator. As recurrences have been described with each of these techniques, every non-surgically-treated false aneurysm should be monitored for 24 hour with ultrasonography control to ensure effective thrombosis.

Aneurysm, False↗
PubMed2003

[Clinical and ultrasonographic follow-up after femoro-popliteal venous bypass for lower limb revascularization].

Revascularisation of the lower limbs with vein graft is frequent. Femoro-popliteal infrainguinal bypass have good permeability rates at five years. The weak point of autogenous vein bypass grafting is vein graft stenosis, which develops particularly in the first post-operative year. Stenoses are mostly in relation with myo-intimal hyperplasia and are often located at anastomoses. Serial arteriography and echographic studies have shown that the development of intrinsic graft stenosis is found in 20 to 30% of vein conduits in the lower extremity. On the basis of an abundance of clinical data, Duplex ultrasound surveillance of infrainguinal vein graft to detect and repair such lesions before graft occlusion is widely accepted and has shown in many retrospective studies to have a positive influence on lifetime of venous grafts. Critical stenosis (peak systolic velocity (PSV) > 300 cm/s and velocity ration (VR) > 4) should undergo surgical revision as it heralds occlusion of the vein graft in short delays. Intermediate stenosis (peak systolic velocity (PSV) 200-300 cm/s and velocity ratio (VR) 2-4 should be accurately followed as 50 to 70% progress to critical stenosis. Use of echo-doppler monitoring is supported by one randomised study which showed superiority of ultrasound surveillance over clinical surveillance, and by a well described relation between graft thrombosis and an increased amputation rate. In contrast, Duplex ultrasound surveillance for prosthetic grafts is not widely accepted primarily because of the occurrence of rare intrinsic lesions in prosthetic grafts, compared to in vein grafts. Vascular doctors are increasingly concerned with the costs of surveillance program and of surgical interventions. Recent economic appraisal have shown that cost associated with graft maintenance is significant, particularly in the first-year and demands consideration. However revision of a duplex-identified stenosis seems to be less costly than revision after graft thrombosis. Costs of limb amputation and the following expense of postamputation rehabilitation are very high and justify limb-salvage-related expense. The results of an ongoing randomised controlled trial (the Vein Graft Trial) comparing duplex ultrasound surveillance against clinical surveillance only will certainly bring more data on the benefits of echographic surveillance.

Femoral Vein↗
PubMed2002

[Genetics of lymphedema: from Milroy's disease to cancer investigations].

New insight has recently been obtained into the molecular mechanisms regulating lymphatic development and function during embryogenesis. VEGF-C and D ligands have been shown to stimulate lymphangiogenesis and their lymphatic-specific receptor VEGFR-3 is linked to the human congenital and hereditary lymphedema in humans. Above all, new focus on lymphatic endothelial cells gives opportunities for developing innovative therapies for lymphedema and cancer metastasis.

Endothelial Growth Factors↗
PubMed2000

[Manual lymphatic drainage].

Manual physiotherapy of lymphoedema is the best treatment for chronic venous and lymphatic stasis of the lower limbs. It consists in handlings of the limb for the appeal and the resorption of the lymph but it cannot be used alone. It must be associated with other techniques: defibrosing, skin care, compressive bandages, muscular exercise. Contensive and compressive bandagings prolong the action of lymphatic drainage. The main indication of manual physiotherapy is primary or secondary lymphoedema but also chronic venous disease, and in some selected cases acute venous thrombosis and traumatic or post-traumatic pains.

Bandages↗
PubMed1997

Diagnosis of acute lower limb deep venous thrombosis with ultrasound: trends and controversies.

Acute deep venous thrombosis of the lower limb is a common and threatening condition whose clinical diagnosis is known to be unreliable. Sonography has gradually superseded venography as the primary diagnostic procedure. A review of the medical literature shows that sonography offers a high level of sensitivity and specificity in symptomatic patients but suffers from a lack of sensitivity at the calf level and in asymptomatic patients. Technologic progress, as well as increased operator experience, may improve sensitivity. Nevertheless, several critical issues remain unresolved, such as the significance of free-floating thrombi, the usefulness of calf and bilateral examination, the criteria that are essential to the diagnosis, the risk of compression sonography, and sonography's role in the direct detection of venous emboli.

Acute Disease↗
PubMed1997

[Criteria for quantification and characterization of aneurysms of the abdominal aorta using ultrasonography. The AFFCA study. French Association of Continuous Education in Angiology].

OBJECTIVE: To validate ultrasonographic quantification and characterization criteria for aneurysms of the abdominal aorta (AAA) by comparing computed tomography data and surgical findings in order to standardize diagnosis and follow-up of AAA. PATIENTS AND METHODS: A multicentric prospective study included 80 patients with AAA (January to August 1996). Standardized data on quantitative (diameter, surface area) and qualitative (topography, form, wall, thrombus) data were obtained at each ultrasound examination and at surgery. Ultrasound (US) and computed tomography (CT) explorations were performed and interpreted without prior knowledge by independent operators. US findings versus CT reference were compared in 77 cases, US findings versus surgical reference in 31, and CT findings versus surgery reference in 28. RESULTS: Compared with CT-scan, B mode ultrasound (n = 77) underestimated the anteroposterior diameter of the aneurysm (mean difference -2.16 mm; p < 0.001), the anteroposterior diameters of the flow channel lumen (-5.54 mm; p < 0.001) and upper neck of the aneurysm (-2.74 mm; p < 0.001). Surface area measurements were not significantly different both the aneurysmal sac (p = 0.3) and the flow channel lumen (p = 1). Compared with surgical findings, US (n = 30) underestimated the transverse diameter (mean difference (-4.29 mm; p = 0.0037). Compared with surgery, US findings (n = 28) were not significantly different for the anteroposterior ans transverse diameters. Analyzing the form and wall of the AAA, US/CT-scan performance was good for symmetrical fusiform aneurysms (sensitivity 77%, specificity 67%). US and CT-scan were reliable for detecting wall bugles (same sensitivity, 29%). The angle formed by the thrombus with the wall (expressed in degrees) was not significantly different (p = 0.9). When the lower pole of the aneurysm was situated above the aortic bifurcation, US (sensitivity 75%) was more reliable than the CT-scan (sensitivity 50%) compared with surgical findings. CONCLUSION: Ultrasonography should not be limited to the simple positive diagnosis of AAA. A precise analysis of the diameters and surface areas of the aneurysm should be performed.

Aged↗
PubMed1997

[The venous valve: non-invasive imaging of its functioning].

B Mode and TM mode Imaging are useful tools to illustrate directly the venous valve motion. Using B Mode, venous valve are echogenic with a particular kinetic as regards its topography. So it's possible to determine in TM Mode a "pseudo-cardiac" valvular motion (jugular vein) and a "pseudo-diaphragmatic" motion for the lower limbs veins. Valvular motion assures unidirectional venous flow.

Humans↗
PubMed1996

[Lymphoscintigraphic aspects of the effects of manual lymphatic drainage].

Manual lymphatic drainage is used in physiotherapy of limb lymphedema in combination with other physical techniques. In order to assess the effectiveness of the method, 47 patients with upper limb lymphedema after radiosurgical therapy for breast cancer underwent lymphoscintigraphy. The examination was performed after subcutaneous injection of technetium-labeled colloid via the fourth and first interdigital space on the hand of the limb with lymphedema. The level of the technetium label was compared on scintigraphies performed before and after manual lymph drainage. Results were analyzed as a function of the clinical characteristics of the edema. Manual lymphatic drainage produced an effective progression of the label in 25 cases (53.2%), independent of radiotherapy. Contralateral lymph nodes were reached in 5 cases and the homolateral internal mammary nodes in 2. These nodes were visualized only after manual lymphatic drainage. The visualization of the drainage routes in unexpected areas demonstrated the effectiveness of the technique in stimulating accessory routes useful for resorption of lymphedema. The use of two injection sites on the hand is also discussed. This study demonstrated the effect on a single session of manual lymphatic drainage and should be completed with an assessment of a complete series of manual lymphatic drainages.

Adult↗
PubMed1994

Effect of subclavian syndrome on the basilar artery.

Fifty-five patients with a permanent or intermittent subclavian steal syndrome demonstrated by continuous wave Doppler were included in a prospective study: 25 patients without vertebro-basilar symptoms, 8 symptomatic patients with defined vertebro-basilar symptoms and 22 with hemodynamic vertebro-basilar occurrences. The basilar artery velocity was recorded by Transcranial Doppler Sonography in baseline conditions, and after a hyperaemia test to the upper limb. A spontaneous, incomplete basilar steal was diagnosed in seven patients, and a complete basilar steal in one patient, (14.5% of the cases). After hyperaemia test, 18 other incomplete basilar steal were observed. The occurrence of a basilar steal was higher in the vertebro-basilar group (57% of the cases) especially in 7 of the 8 cases with defined vertebro-basilar symptoms; it was lower in the patients without vertebro-basilar occurrences (36% of the cases). This basilar steal was also seen in five of the six symptomatic patients with opposite vertebral artery stenosis above a 50% diameter. Transcranial Doppler Sonography could help to define a subgroup of subclavian steal syndrome with a high risk of strokes.

Adult↗
PubMed1992

[Diagnosis by Doppler color echography of dural carotid-cavernous fistula of ophthalmological manifestation].

The case reported here, concerns a spontaneous low-flow fistula between the external carotid arterial network and the cavernous sinus, with ophthalmological symptoms (exophthalmos, red eye) in an old woman with cardiac failure. The shunt was diagnosed by color-Doppler-imaging, which showed a flow reversal with a systolic component in the superior and inferior enlarged ophthalmic veins. This finding led the authors to extend the arterial filling sequence since the shunt was not detectable on standard arterial views. Embolization was performed during angiography which remains necessary to localize the shunt and to treat the fistula. The clinical symptoms progressively returned to normal and the correction of the hemodynamic disturbances could be followed by color-Doppler imaging, a non-invasive technique which can be easily repeated.

Aged↗
PubMed1989

[Medical, social, economic value of the rational use of non-invasive studies for diagnosing phlebitis. Experience of the Regional Hospital Center of Nimes from 1984 to 1988].

Continuous wave Doppler, and B-Mode ultrasound allow the diagnosis of deep venous thrombosis with a 96% sensitivity, and a 98% specificity versus venography (1). Therefore, these methods can be extensively used for the detection of deep venous thrombosis, following a new diagnostic algorithm: X ray venography is used only for the assessment of topographic extent of iliac and caval thrombosis, and when non invasive methods give equivocal results. As a result, the number of X ray venographies significantly decreased since 1984 (7) in Nîmes University Hospital. About 75% of patients with a deep venous thrombosis (diagnosed by non invasive methods) were treated without necessity of X ray venography.

Algorithms↗
PubMed1986

Real-time B-mode ultrasonography for better specificity in the noninvasive diagnosis of deep venous thrombosis.

In order to evaluate the usefulness of B-mode ultrasonography in the diagnosis of deep vein thrombosis, a prospective study was performed on 145 patients. Each patient was examined with occlusive venous plethysmography, continuous wave Doppler, real-time B-mode ultrasonography, and radiographic contrast phlebography. The diagnostic sensitivity and specificity versus phlebography were 91 and 82.1 per cent, respectively, for plethysmography, 92 and 86.6 per cent for Doppler, and 94 and 100 per cent for B-mode sonographic scanning. The combined noninvasive approach reached a 96 per cent sensitivity. B-mode ultrasonography demonstrated a mass in eight cases, and showed a superficial venous thrombosis in four cases, among the 45 patients without deep vein thrombosis. B-mode ultrasonography, therefore, appears to be very useful in obtaining a better specificity and differential diagnosis.

Adolescent↗
PubMed1984

[Ultrasound measurement of portal blood flow. Initial results in the study of hemopathies].

Portal blood volume was non invasively evaluated with pulsed Doppler ultrasound coupled with automatic, water path echotomography (U. I. Octoson). This measurement was successful in 18 from 24 normal volunteers, the portal flow values being 14.25+ or -4.5 ml/min/kg. The portal blood flow measurement was possible in 16 from 17 patients with hemopathy. Portal flow volume was greatly increased in 11 cases (more than 23 ml/min/kg), in connection with splenomegalia. It was moderately high in 3 cases, from whom 1 without splenomegalia and 1 splenectomised. Portal flow was normal in 1 case and was reduced in 1 case (with high splenic blood flow, in a patient with portal hypertension due to portal vein compression by adenopathy). Portal blood flow increase seems to be connected with splenomegalia. Manometric portal hypertension seems to be more clearly connected with hepatic invasion by hemopathy.

Adult↗