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Biomedical subjects

R Duvauferrier

Publications and source records attributed to R Duvauferrier.

At least 55 records · Page 3Linked to original sources
PubMed1996

Limitations of hyperselective intraarterial injections for the treatment of hepatocellular carcinoma.

The authors report the case of a cirrhotic patient with a multinodular hepatocellular carcinoma. Two nodules were located in the right liver lobe and a minute nodule was in the left lobe. Because of poor liver function, two injections of iodine-131-labeled Lipiodol were delivered in the right hepatic artery to protect the left lobe. The efficacy was obvious in the treated areas, but the minute lesion enlarged dramatically and was responsible for the patient's death.

Aged↗
PubMed1996

[Preliminary evaluation of the performance of 3D morphometer and spiral scanner in carotid stenoses].

Carotid stenosis evaluation is now possible with 3D Imaging. We prospectively compared the diagnostic value of Spiral CT and 3D Morphometer with conventional intraarterial DSA considered as the gold standard. We studied 19 bifurcations in 10 patients. We evaluated the stenosis following the NASCET guidelines on the DSA, with common carotid injection, on the 3D databases of 3D morphometer and of spiral CT (using MIP display). There was a good correlation between the degree of stenosis calculated with the 3D morphometer and angiography even if severe stenoses were slightly overestimated with the former. For the spiral CT databases, accurate diameters were impossible to obtain in case of huge calcifications. There was no benefit of measuring the surfaces on reoriented axial views in comparison with native axial views and MIP images. With the 3D morphometer, post processing selective visualization of the carotid bifurcations is possible without selective injection. The 3D acquisition with 3D morphometer could be an additional acquisition of a standard DSA. It should replace selective injections and should reduce the side effects of angiography.

Angiography↗
PubMed1996

[Multimodal approach to carotid bifurcation in atherosclerosis].

The cost of treatment of ischemic stroke (second cause of death for elderly patients) is increasing. carotid bifurcation surgery can change the prognosis (as proven by NASCET and ECST studies) for symptomatic patients with over 70% of carotid narrowing. Exploration of the carotid bifurcation is an important step in the diagnosis and must assess the degree of stenosis, the smoothness of the plaque and describe the collateral vessels. Duplex sonography is used to analyze the plaque and to measure the hemodynamic consequences beyond the stenosis. Transcranial Doppler is used to study the hemodynamic consequences at the circle of Willis. 3D TOF MR Angiography visualizes vessels using MIP but with a risk of overestimation of the degree of stenosis. A good morphological study of the circle of Willis can be achieved. With spiral CT, 3D data bases can be acquired with a single injection of contrast medium. Analysis is based on native, reformatted and MIP images. The image quality is generally good, but decreases in the case of huge calcifications. Brain examination can be performed in the same session, looking for rupture of the blood-brain barrier. Angiography remains the gold standard with a high complication rate. It allows excellent analysis from the aortic arch to distal cortical vessels. Isotope studies are only performed in difficult cases (vertebro-basilar lesions, differential diagnosis). Duplex ultrasound is performed first in all protocols. Until recently, angiography was performed before surgery, but the current tendency is to use a less invasive examination (MR angiography or CT angiography) and angiography is then only performed when necessary. A knowledge of the respective advantages of each technique is essential in order to adapt the protocols to each local team.

Angiography, Digital Subtraction↗
PubMed1995

[Image data bases and multimedia works on server and CD-ROM in medical imaging. A French experience].

The CD-ROM technology allows the production of multimedia works which costs far less than books do. The creation of Internet and the servers World Wide Web has the advantage of distributing those works world wide, without the difficulties and the delays related to books and magazines distribution. The Teachers' Council of Radiology of France (CERF) and the French Society of Radiology (SFR) have opted to use these new media and these information highways to spread a part of their radiology teaching work. Iconocerf is a software program which allows to create, store, read and to exchange digitized radiological cases. It's available free of charge, within the CERF and SFR. The CD-ROMs Iconocerf-Medimag contain 3,500 radiological files with 15,000 images, previously on the videodisc Medimag. The Server of the French Radiology is a W3 server which includes: the CERF directory, a guide for the teachers, the research workers and the students in Radiology and Medical Imaging. It also contains the teaching works on Radiology, and some Iconocerf clinical cases translated onto HTML. The aim of this project is to create an evaluation system for radiology. By using key words, this system allows to consult: radiological clinical cases, located on the server or on CD-ROMs; reference texts; and to have access to the experts' addresses to be able to send them eventually a difficult case through electronic mail.

CD-ROM↗
PubMed1995

[Analysis of texture in medical imaging. Review of the literature].

This paper presents a review of the applications of texture analysis in medical imaging. Many authors take a great interest in this topic (75 papers have been published since 1984) and try to elaborate automatic methods for tissue characterization. The results are not really convincing and applications are often reduced to feasibility studies. This failure is due to the empirical approach to the problem: the first studies were performed on ultrasound images, in which visual texture is very present, but no data standardization is available with this imaging modality. A more rational approach should provide better results. For each organ or tissue, it is necessary to find the appropriate source and texture analysis method. This difficult task requires reflection concerning the interactions between tissues and imaging sources, to define judicious structuring elements. These structuring elements should facilitate the choice of the best texture analysis method, for the particular application. Considerable methodological progress has yet to be made, after which texture analysis should be a useful and efficient tool for clinical use.

Humans↗
PubMed1994

Randomized controlled trial for hepatocellular carcinoma with portal vein thrombosis: intra-arterial iodine-131-iodized oil versus medical support.

UNLABELLED: Portal vein thrombosis is a poor prognostic factor in patients with hepatocellular carcinoma (HCC) and a contraindication for chemoembolization. Intra-arterial injection of 131I-iodized oil which does not modify arterial flow, is feasible in this condition. The aim of this prospective randomized controlled trial was to compare the efficacy of treatment with radiolabeled oil (treated group) versus medical support (control group) in patients with stage I or II HCC (classification of Okuda) with portal vein thrombosis. METHODS: Twenty-seven HCC patients (26 males, 1 female), aged 53-79 yr, with portal vein thrombosis were randomly assigned to Lipiocis group (n = 14) or Control group (n = 13). Additional injections of radiolabeled oil were given 2, 5, 8 and 12 mo after initial therapy. Medical support treatment consisted of: tamoxifen (n = 5), 5 FU intravenously (n = 1), NSAIDs or corticosteroids (n = 5). Efficacy was evaluated according to survival rate (Kaplan-Meier method; log rank test), AFP serum values (measured at 2, 5, 8 and 12 mo) and angiography. RESULTS: The two groups were comparable (Child's classification, Okuda's classification, liver function tests, location of the thrombus). Tolerance was excellent in the Treated group. The actuarial survival curves were significantly different (p < 0.01) between the two groups, the survival rates (Cl 95%) at 3, 6 and 9 mo being 71% (48%-95%), 48% (12%-55%), 7% (1%-31%) for the Treated group; and 10% (1%-33%), 0% and 0% for the Control group. CONCLUSION: Intra-arterial hepatic injection of 131I-labeled iodized oil is a safe and effective palliative treatment of HCC with portal vein thrombosis.

Adrenal Cortex Hormones↗
PubMed1994

[Study of the correlation between magnetic resonance imaging and surgery in the diagnosis of chronic Achilles tendinopathies].

Eighteen cases of chronic lesions of the heel cord were evaluated by MRI and operated. The sensitivity of MRI is high in detecting intratendinous lesions (positive predictive value of 0.94); this sensitivity is linked with an unsurpassed anatomical precision. The specificity in the diagnosis of intratendinous lesions is limited as regards partial rupture versus chronic inflammation. This technique can be improved by systematically making fine cuts in the transverse plane, absolutely perpendicular to the heel cord.

Achilles Tendon↗
PubMed1994

[Aspects and value of MRI in the diagnosis and follow-up of common microbes infectious spondylodiscitis. Apropos of 25 clinically and biologically suspected patients].

This work is about 25 patients clinically and biologically suspected of spondylodiscitis (27 levels). All of them had a MRI exam before disco-vertebral needle biopsy and treatment. The results are compared to those of literature. Each infectious spondylitis case (19 cases) had a new MRI exam each three months. This study conclude to the great sensibility of MRI (89%) in the diagnosis of infectious spondylitis and to the limited interest of it in the follow-up of spondylodiscitis.

Adolescent↗
PubMed1994

[Evaluation of the scanner and radiography in rheumatic pelvispondylitis].

We studied 20 normal subjects and 20 suffering from sacro-iliitis. The performance of the two techniques were compared in studying reports ROC curve from several readers. We assessed the performance of each technique and each sign: CT scan appears as a better technique than plain films. Some signs present a poor interest: osteophytes seen on CT or plain films, subchondral cysts seen on CT. In other respects, articular cartilage erosions, subchondral sclerosis are main signs as much on CT as on plain films. In conclusion, CT scan allowed an accurate analysis of sacro-iliitis. It has a better diagnostic value than plain films and, in case of doubt, should be performed to increase diagnosis sensibility and specificity.

Adult↗
PubMed1993

Usefulness of hepatic artery injection of iodized oil and 131I-labeled iodized oil before the therapeutic decision in hepatocellular carcinoma.

This study assesses the usefulness of intra-arterial injection of iodized oil (Lipiodol) as a tool for evaluating the therapeutic choice in a series of 72 consecutive patients with hepatocellular carcinoma (HCC). In 52 of these patients a scintigraphic study of the biodistribution of iodized oil was done, using 131I-iodized oil injection. A single tumor was detected in only 17 cases; 18 patients had a tumor involving only 1 lobe; in 7 cases CT scan disclosed a minute nodule in the opposite lobe of the main tumor. Eighteen patients had a portal thrombosis; in 12 of these cases CT scan showed iodized oil in the tumor emboli. The degree of intratumoral retention of iodized oil depended on the size of tumors and on the presence of arterioportal shunts. Our study demonstrates that only a few patients (4%) with HCC might benefit from curative surgery. The therapeutic benefit of methods using iodized oil injection might be estimated by means of its biodistribution variables (CT and/or scintigraphic data).

Adult↗
PubMed1993

[Digital library for archiving files of radiology and medical imaging].

The Conseil des Enseignants de Radiologie de France in collaboration with the Ilab-TSI company and Schering laboratories has developed a computer programme allowing the storage and consultation of radiological teaching files. This programme, developed on Macintosh from standard Hypercard and Quicktime applications, allows, in consultation mode, the multicriteria search and visualisation of selected radiological files. In the author mode, new files can be included after digitalizing the author's own images or after obtaining images from another image library. This programme, which allows juxtaposition of digitalised radiological files, is designed to be extremely open and can be easily combined with other computer-assisted teaching or computer-assisted presentation applications.

Audiovisual Aids↗
PubMed1992

Chemoembolization of hepatocellular carcinomas. A study of the biodistribution and pharmacokinetics of doxorubicin.

BACKGROUND: This study evaluated the effects of an association of ethiodized oil (Lipiodol Ultra Fluide, Laboratoires Guerbet, Aulnay-sous-Bois, France), with or without gelatin sponge, with doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH) on the biodistribution and kinetics of doxorubicin during intraarterial injection. METHODS: Eighteen patients with hepatocellular carcinoma on cirrhotic liver received a therapeutic injection into the hepatic artery of 50 mg of doxorubicin alone (Group 1; n = 4), or emulsified in 10 ml of ethiodized oil and 2.5 ml of ioxaglate (Hexabrix, Laboratoires Guerbet) with (Group 2; n = 7) or without (Group 3; n = 7) gelatin sponge embolization. Before treatment, the absence of intrahepatic shunts was verified by an injection of technetium-labeled albumin macroaggregates. The biodistribution of doxorubicin was studied on two fronts: (1) pharmacokinetic--by measurement of the doxorubicin blood level during the 48 hours after injection; and (2) scintigraphic (2 mg of doxorubicin were labeled with 2 mCi of iodine 131)--by examination of the scintigrams and calculation of the following parameters: tumours liver/nontumorous liver binding ratio (T/NT ratio), liver/liver+lungs+abdomen binding ratio, and doxorubicin half-life in tumorous tissue. RESULTS: Pharmacokinetics results showed the following: the peak plasma concentration was significantly higher in Group 1 as compared with Groups 2 or 3 (Group 1: 2.1 +/- 0.9 mg/ml; Group 2: 0.9 +/- 0.3 mg/ml; Group 3: 0.5 +/- 0.2 mg/ml); the area under curve calculated from time zero to 1 hour was lower in Groups 2 and 3 compared with Group 1. Examination of the scintigrams showed the following: diffuse activity throughout the organism (Group 1), diffuse activity with strong hepatic and tumorous binding (Group 2), and mostly hepatic and tumoral binding (Group 3). The liver/liver+lungs+abdomen binding ratio was 28% +/- 1% in Group 1, 36% +/- 5% in Group 2, and 63% +/- 7% in Group 3. The T/NT ratios were 1.0 +/- 0 (Group 1), 1.5 +/- 0.1 (Group 2), and 4.7 +/- 0.5 (Group 3). The doxorubicin half-lives in tumourous tissue were 0.7 +/- 0.1 days (Group 1), 1.8 +/- 0.2 days (Group 2), and 2.6 days (n = 1; Group 3). CONCLUSIONS: This study shows (1) that the association of ethiodized oil with doxorubicin lowers the peak concentration of doxorubicin and increases the intratumoral concentration and half-life of doxorubicin, and (2) that these kinetic ameliorations are even more pronounced after embolization. Therefore, from a kinetic standpoint, the doxorubicin-ethiodized oil-gelatin sponge association is the best.

Aged↗
PubMed1991

[The new organizational approach introduced by interventional radiology].

The primary approach to the interventional radiology is to substitute what could have been a major intervention by something done on either in the out-patients department or during a brief hospitalization. This evolution on the medical practice is coupled with the problem of a multidisciplinary team (radiologist, anesthetist, surgeon organ specialist) approach oriented to the same technical platform.

Hospital Restructuring↗
PubMed1990

[Recurrent postoperative sciatica. Prospective evaluation of magnetic resonance imaging and x-ray computed tomography with iodine injection].

The respective performance of MRI and CT were studied prospectively in 80 cases. Surgery was indicated in 56 patients after MRI examination and 21 patients after CT; the 21 patients were included in the 56. Among these patients, 45 were reoperated and 11 preferred the medical treatment. Surgery confirmed the diagnosis for 44 patients (from the 45), and the only discordance was the presence of ligament calcification, associated to a disc protrusion not seen on MRI. Surgery confirmed also the diagnosis for the 21 cases diagnosed by CT after iodine injection. However, among the 24 cases of fibrosis diagnosed by CT after i.v. injection were found: 19 recurrent disc protrusions, 4 disc protrusions with fibrosis, and 1 disc protrusion at a level above the operated disc.

Adult↗
PubMed1989

MRI anatomy of the nerves of the upper limb.

In view of the good anatomic definition of the images obtained by magnetic resonance imaging (MRI), we have defined MRI sections allowing study of the nerves of the upper limb.

Arm↗