PubMed Health⌕ Search

Biomedical subjects

J D Picard

Publications and source records attributed to J D Picard.

At least 19 recordsLinked to original sources
PubMed1990

[Current status of research of a lymphatic system in the nervous system: initial trials with cerebral lymphography].

After having recognized the existence of post-mortem intra-cerebral circulation of a coloring substance with lymphatic resorption, the author is continuing his research by injecting a product sharing the same characteristics: Iotrolan. Brain X-rays show brain circulation from the cortex to the ventricular cavities and from the spinal cord to the bulbar area and to the cerebellum. One question deserves to be asked: what is this circulation?

Animals↗
PubMed1990

[In search of the lymphatic system of the central nervous system].

Lymphatic flow in the brains and lymphatic vessels in the meninges are recognized through the intra-cerebral injection of a dye specific to the lymphatic system. The confluence of these two components can only be at the level of the cerebro spinal fluid (CSF), which lends support to the hypothesis that the CSF itself constitutes the lymph of the nervous system. The authors report the results of a study based on a necropsic investigation and an experimental animal model, contributing new facts in favor of this hypothesis. For a certain number of inflammatory diseases of the central nervous system (CNS) when the initial phase is still limited to the brain or to the spinal chord tissues, it is usually asymptomatic; only when it reaches the meninges, that clinical symptoms be seen: this can be explained by the presence of such lymphatic circulatory system. Stasis of the cerebral lymphatic circulation, should be regarded as a new etiologic factor in the onset of brain oedemas. This concept, already taken into account by some investigators, deserves consideration in the study of most CNS diseases.

Animals↗
PubMed1989

[Pitfalls in phlebography].

Despite the progress in functional investigation procedures, phlebography remains the standard test in venous disease of the lower extremities. The development of better quality contrast media has significantly improved patients tolerance. After a review of the regular, routine procedure, the authors stress the technic's pitfalls. Uncomplicated pitfalls are air bubbles, Venturi's effect, venous malformations, and superimposed venous axes or gases. This type of problems is easily circumvented. Flow images caused by confluent axes of high-flow veins (internal iliac veins, renal veins) or layer courants (gutter effect) are presented as a reminder. Compression images are often more treacherous: related to normal veins: compression of left iliac vein by aortic junction; of inferior vena cava by enlarged aorta or by osteophyte; tourniquet too low, iliac vein compressed by a dilated bladder; or compression due to intramuscular hematoma,... related to pathological veins: to be mentioned are bridle-caused obstruction of the popliteal vein (Klippel-Trénaunay syndrome), and retroperitoneal fibrosis. Although the present description of phlebography-related pitfalls is neither new, nor exhaustive, it should be reconsidered, as phlebography of the lower limbs, while being currently better tolerated, is still an update technic that needs to be rendered more reliable.

Constriction↗
PubMed1983

[Tomodensitometry in pheochromocytomas].

An atlas of the various appearances of pheochromocytoma on CAT scanning demonstrates the value of this method. Most diagnostic problems can be resolved whatever the presenting signs. This investigation locates the tumour(s) and determines their extension, so constituting an essential part of the preoperative work-up.

Adrenal Gland Neoplasms↗
PubMed1982

[Angioplasty of the arteries of the extremities. Early and mid-term results (up to 3 years) in 492 cases].

Results of iliac, femoral and/or iliac artery percutaneous transluminal angioplasty (P.T.A.) in 492 cases are presented, and the latest technical improvements in the procedure reviewed. Short and medium-term results in iliac artery stenoses were excellent (98 and 96% respectively), obstructions in this region not being treated. The advantage of P.T.A. over surgery is the lack of exposure of patients to the risk of circulatory insufficiency. Very good results were obtained in stenosis of the distal femoral artery, the method being much less effective in cases of long thrombosis. The essential indications are all types of stenosis of limb arteries, while contraindications can be summarized as iliac artery obstructions (because of possible severe retroperitoneal hematomas) and massive atheromatous calcifications. Aortic and graft stenoses are particular indications. Complications are mainly hematomas and thromboses, but these can be reduced in incidence by increasing experience of radiologists in the use of P.T.A. and by improved selection of patients. Progress will also depend on improved control of anticoagulant and thrombolytic treatments. The question is raised as to the need to treat early claudication due to femoral artery stenosis following detection by the Doppler effect test. The essential argument in favor of P.T.A. is the simplicity and safety of the method to the compared reconstructive surgery, a method involving too high a risk.

Aged↗