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Biomedical subjects

R Duvauferrier

Publications and source records attributed to R Duvauferrier.

At least 19 recordsLinked to original sources
PubMed2006

[Diffusion weighted MRI of spine tumors].

PURPOSE: To evaluate the contribution of diffusion weighted MR imaging in malignant spine pathology. Materials and methods. Between February 2004 and January 2005, 49 patients (43 to 86 years old) were included. Three groups were made: osteoporotic collapses (n = 13), malignant collapses (n = 15) and malignant spine lesions (n = 21). The MRI (Symphony 1.5T) allowed SENSE imaging. After conventional MRI examination (T1, T2 fat sat, T1 with Gadolinium), all patients underwent diffusion weighted imaging (Spin Echo) with variable b values: 0, 250, 500, 750 and 1000. The diffusion sequence lasted 2 min 29 s. The Apparent Diffusion Coefficient (ADC) was calculated automatically. The analysis was qualitative (signal study b = 1,000 mm2/s) and quantitative (ADC measurement). RESULTS: The image quality was good except for some cervical examinations. Qualitative analysis did not show a difference between benign and malignant lesions. Quantitative results are: malignant spine lesion (mean ADC = 0.826 10-3 s/mm2), malignant spinal collapses (mean ADC = 0.912 10-3 s/mm2) and benign spinal collapses (mean ADC = 1.497 10-3 s/mm2). There was overlapping results between benign and malignant lesion. The statistical study showed a significant difference (t test with p < 1/10 000). For an ADC threshold value of 1.089 (malignant lesion ADC < 1.089), ROC curve showed a specificity = 80% and a sensitivity = 83.3%. CONCLUSION: Performing diffusion weighted imaging of the spine is easy with new MR technology. The ADC measurement of spine lesion provides important additional information, but does not serve as a substitute for the routine MRI sequences. In the future, it could become an important point in this difficult diagnosis.

Adult↗
PubMed2006

[Synovial biopsy under US guidance: technical considerations and results].

PURPOSE: To describe and assess ultrasound (US) guided biopsy of peripheral joint synovial membrane. METHOD: Between January 2002 and January 2005, 83 patients have undergone biopsies of synovial membrane performed under ultrasonographic guidance, as a diagnostic procedure for monoarthritis of unknown etiology. After synovial thickening was confirmed by US examination, the optimal approach to the joint was decided in accordance with maximal synovial thickening localization and adjacent anatomic structures. The absence of complications related to the biopsy was verified by continuous ultrasonographic scanning during and immediately after the procedure. The procedure was rated as successful if synovial tissue was identified by histologic examination of the biopsy specimen. Success rate of the procedure was compared to the fluoroscopic guided biopsy success rate that was formely published in medical literature. RESULTS: Synovial tissue was obtained in 78 cases (94%) (shoulder (100%), elbow (75%), wrist (85.7%), hip (88.2%), knee (97%), ankle (100%). No complication occurred. CONCLUSION: US guided biopsy of peripheral joint synovial membrane is a safe and effective technique that has multiple advantages compared to fluoroscopic guided procedure.

Adolescent↗
PubMed2005

Monitoring incident report in the healthcare process to improve quality in hospitals.

Healthcare organizations are facing growing pressures to adopt intelligent technology to promote quality and safety care in public and private hospitals. In 2000, the Institute of Medicine report also indicated that an estimated 44,000 to 98,000 Americans die annually as a result of preventable medical errors and it appears that information management in hospitals can help the organization to improve the quality level. This paper aims to present an experience in the management of events not compliant with the best practice by monitoring these events in a hospital. We used ISO standard to implement general quality process and quality management. This project consists in proposing the possibility of declaring different dysfunctions and incidents by a simple form integrated into the intranet services of the hospital for the medical, nursing and administrative staff. This should lead to quality management of the medical units.

Benchmarking↗
PubMed2005

[Vertebral trabecular network analysis on CT images].

PURPOSE: Comparing texture analysis, density measurement and visual quantification of trabecular network on spine CT images, to better evaluate bone architecture in osteoporosis. METHOD AND MATERIALS: Seventeen patients, aged 19 to 84 years, were included. One patient presented osteoporotic fractures. High resolution computed tomographic (HR-CT) images of the third lumbar vertebra were acquired using a Somatom 4 plus CT (Siemens) in a strict axial orientation with FOV of 12 cm and slice thickness of 1 mm. The size of the Region Of Interest was 1,6 cm(2). Three analyses were performed on this ROI: Density (in Hounsfield Unity), texture analysis (run length) and features inspired from bone histomorphometry (Bone Volume/Tissue Volume). RESULTS: Density measurement, run length methods and BV/TV provided consistent results with regards to age. Indeed density, run length and BV/TV results were lower for older patients with more advanced bone trabeculra alterations. CONCLUSION: Only BV/TV and run length parameters seemed to show additional information on trabecular network architecture. The contribution of these two measurements to diagnose and classify osteoporosis will be the goal of a clinical study.

Adult↗
PubMed2004

[Evaluation of the efficacy of CT guided thoracic sympatholysis to treat palmar hyperhidrosis].

PURPOSE AND METHOD: Palmar hyperhidrosis is a pathological condition characterized by overperspiration caused by any stress or emotion. We have evaluated the results of 101 CT guided sympatholysis procedures performed on 50 patients suffering from primary palmar hyperhydrosis. RESULTS: Mean follow up was 50 Months (6 Months to 8 Years) for 87 procedures with immediate good results in 46 patients. Using actuarial analysis, 62% of patients had persistent good results after 50 Months. Complications included one case of small pneumothorax requiring no treatment and one case of vagal syndrome. Pain or thoracic discomfort was reported by 14 patients and was relieved by aspirin within 24 hours. Six patients developed a Horner's syndrome that resolved within a few weeks and six other patients developed moderate compensatory overperspiration over the face, thorax or contralateral arm. CONCLUSION: Based on our results, CT guided sympatholysis provides results similar to endoscopic thoracic sympathectomy and is associated with fewer risks.

Adolescent↗
PubMed2004

[Management system for patients requiring stereotactic macrobiopsies of the breast: report on 100 patients].

PURPOSE: The authors describe and evaluate the management system for patients requiring large core vacuum-assisted biopsies at a dedicated breast center. This process includes mandatory review of all requests by a multidisciplinary team. MATERIAL: and method. Patients were provided questionnaires to evaluate their degree of satisfaction with the management process. Results from biopsy and surgery were retrospectively reviewed. RESULTS: From the 100 patients included in the study (106 macrobiopsies), 95,28% of biopsies were informative. The degree of correlation between the histological diagnosis from biopsy and surgery was 86,95% for the 46 operated cases. The degree of acceptability by patients as well as medical and non-medical staff was satisfactory. CONCLUSION: The original feature of this process is the retrospective review of all charts after the histological results becomes available for final validation of the biopsy results and management. The results of the biopsy and the post biopsy management are provided by the initial referring physician, allowing optimal patient care and follow-up.

Adult↗
PubMed2003

Tracing computerized incidents to manage and improve quality health care in hospitals.

The promotion of quality and safety care in public and private Hospitals has become a crucial stake. To succeed in this, a quality process is necessary for quality management. To set it up, it is necessary to have different piloting tools. Data collection of effective information is one of these tools. It is necessary to be able to process the data quickly in order to answer the various demands rapidly. This project consists in proposing the possibility of declaring different dysfunctions and incidents by a simple formula integrated into the intranet services of the hospital for the medical, nursing and administrative staff. This should lead to quality management of the medical units.

France↗
PubMed2003

[CD-ROM burning of CT scan images: initial experience].

OBJECTIVES: To evaluate the cost, the functionment and the impact of the installation of a CD-ROM burning system of CT scan images. MATERIALS AND METHODS: An automated CD-ROM burning system (e-patient*, TSI, Paris, France) allows to burn CDs for CT scan examinations containing more than 4 films. During a 3 month period, we have delivered for each examination a CD-ROM including images with a Dicom viewer and a selection of interesting images printed on one film. The system has been evaluated by the technologists, the radiologists and the referring physicians by means of a questionnaire. The costs and the technical problems have also been studied. RESULTS: The benefits of our system are the increase of the diagnostic performances of the referring physicians who use the DICOM format and a reduction of the printing costs. All referring physicians pointed out major changes in their daily work including difficulties to visualize images in relation with a lack of computer infrastructure and the impossibility of simultaneous analysis of several examinations. Technologists encountered technical problems to bum examinations and radiologists had to do extra work to related to image selection. CONCLUSION: The installation of an automated burning system requires the creation of a dedicated team to train all the users and adapt the presentation of results to the clinical constraints (i.e. performing and printing an image selection). This system will not replace the hospital network but will be complementary.

CD-ROM↗
PubMed2002

[Process management in a radiology department. Impact on the quality system].

The purpose of this work was the transition from a mode of management combining TQM (Total Quality Management) based on the European model "EFQM", and quality assurance based on the ISO 9001-1994 certification model, to the ISO 9001-2000 certification model which imposes process management and integrates both management and quality assurance. In order to visualize the inter-relation between processes, a processes-map was made. That is to say a representation of the organization in terms of inputs and outputs. Those processes were divided step by step, from general to final processes which were translated into an algorithmic approach. Subsequently, two external auditors were asked to evaluate the new quality system. They used three quality standards (IOS 9001-2000, MFQ and ANAES) in order to determine the adaptation score of the quality system. Finally, the implementation of the department documentation system on an intranet was evaluated by means of two questionnaires: a qualitative one, dealing with staff acceptability, and a quantitative one, dealing with research effectiveness.

Algorithms↗
PubMed2002

[Efficacy of C1-C2 block with posterior parasagittal approach in the treatment of Arnold neuralgia in 24 patients].

UNLABELLED: The purpose of the study is to evaluate the efficacy of C1-C2 block from a posterior parasagittal approach to treat Arnold neuralgia. MATERIALS AND METHODS: 24 patients have been interviewed after 33 blocks were performed. The mean delay was 22 months. The posterior approach had always been performed using fluoroscopy. 27 blocks were performed with Hydrocortancyl((R)), 6 with Altim((R)). RESULTS: 71% of patients were symptomatically improved after one month, 62% after 3 months and more than 50% after one year. Using a visual analogue scale, pain was reduced of 5.8, i.e. 70% of patients were improved. An important reduction of pain killer requirements was noted for improved patients, patients with pain recurrence asked for a new infiltration. No significant side effect was noted. CONCLUSION: Our method seems to be an efficient alternative to blocks performed on the origin of the nerve and to surgical treatment.

Adult↗
PubMed2002

[Pain management with nerve root block under ct and neurostimulator guidance].

PURPOSE: To evaluate the efficacy of nerve roots block under CT and neurostimulator guidance for the management of pain. MATERIAL: and method. Nerve root blocks were performed in 27 patients (pudendal nerve, intercostal nerve, ilio-hypogastric nerve, thoracic and lumbar sympatholysis). These were performed with corticosteroids (Altim((R))) (20 patients) or phenol (7 patients). RESULTS: Seventeen patients (63%) had pain reduction during at least 15 days. The pain relief was longer with phenol. Complications appeared in the 3 lumbar sympatholysis (inguinal pain) and one of the thoracic sympatholysis (Claude Bernard Horner syndrome). CONCLUSION: The nerve root blocks seem to have some efficacy and a further evaluation is necessary to assess their impact on the ability of patients to return to work and their need for pain medication. When performing these procedures, one must be careful to avoid potential complications and verify that the procedure is needed.

Adult↗
PubMed2001

Forceful sacrococcygeal injections in the treatment of postdiscectomy sciatica. A controlled study versus glucocorticoid injections.

UNLABELLED: The role of epidural fibrosis in postoperative sciatica is unclear. Few therapeutic trials have been published. We evaluated the mechanical effects of forceful saline injections through the sacrococcygeal hiatus comparatively with glucocorticoid injections. PATIENTS AND METHODS: Forty-seven patients with postdiscectomy sciatica but no evidence of compression by computed tomography or magnetic resonance imaging were included in a multicenter, randomized, controlled, parallel-group study comparing forceful injections of saline (20 ml) with or without prednisolone acetate (125 mg) to epidural prednisolone acetate (125 mg) alone. Each of the three treatments was given once a month for three consecutive months. Outcome measures were pain severity on a visual analog scale (VAS) and the scores on the Dallas algofunctional self-questionnaire on day 0, day 60, and day 120. Analysis of variance for repeated measures and Student's t test for paired series were used to evaluate the data. RESULTS: Forty-seven patients were evaluated. The VAS score improved significantly between day 0 and day 30 in the glucocorticoid group as compared to the forceful injection group (P = 0.01). No other significant differences were found across the groups. The VAS score improved steadily in the forceful injection group, producing a nearly significant difference on day 120 as compared to baseline (P = 0.08). CONCLUSION: Forceful epidural injections produced a non-significant improvement in postdiscectomy sciatica four months after surgery. Epidural glucocorticoids used alone induced short-lived pain relief.

Adolescent↗
PubMed2000

Radiology on Internet: advice in consulting websites and evaluating their quality.

Services offered by Internet are increasing continually and 15,000 medical websites covering all the specialties are available presently. Finding relevant information with a spider-web organization is difficult. We recommend starting with hierarchical lists which propose a selection of sites corresponding to medical specialties. We give our selection of important radiological websites dealing with image databases, case reports, radioanatomy and continuing medical education. While surfing the Web, an evaluation of the quality of websites is necessary. We used quality criteria proposed by Darmoni to rate the quality of ten websites. The global quality is good; help pages and external links are the main noticed shortcomings. All webmasters should pay attention to quality criteria and show visible marks of Darmoni criteria on their home page. To be able to foresee which Internet options should be developed, we evaluated our website and sent a questionnaire to our users. Clinical cases are the most requested facilities; they could be used for continuing medical education.

Anatomy↗
PubMed2000

Quantification of carotid stenoses using 3D morphometer, CT angiography and conventional angiography.

BACKGROUND: The aim of this study is to compare the performances of 3D morphometer (M3D) regarding the quantification of extracranial carotid stenoses with selective 2D conventional angiography (reference technique) and spiral CT scan. METHODS: It is a prospective study, including 15 patients (mean age 75) presenting a symptomatic carotid lesion detected via duplex Doppler to be operated. Patients had to hold their breath for 20 seconds. Twenty-nine carotid bifurcations were studied by means of M3D and 2D conventional angiography (15 patients). Only 10 patients (19 bifurcations) underwent a CT scan. The measures were performed on a visual display unit by measuring the pixels as per the NASCET technique. Diameters (MIP technique) and surfaces (reformated axial slices) were measured. RESULTS: With MIP technique, a good correlation was found 20 times in 29 (69%) (overestimation: n=8/29) between M3D and angiography, but only in 9 of 19 cases (47%) between CT scan and angiography. Unlike with M3D, the slices re-oriented with CT scan gave better correlations: 15 times in 19 (79%). With the CT scan, the measures were impossible 8 times on MIP technique, and twice on reformated slices for calcified tight stenoses. Therefore, the quantification by means of spiral CT scan is easier by planimetry on slices. CONCLUSIONS: The reliability of these 3D explorations regarding quantification remains uncertain. The use of a morphometer, provided that technical adaptations are made, could replace selective sequences in multiple incidences that become accessible in the post-treatment period, with an acquisition field larger than the one of the CT scan.

Aged↗
PubMed2000

The French Virtual Medical University.

This paper is the description of a French Virtual Medical University based on the federation of existing or currently being developed resources in several Medical Schools in France. The objectives of the project is not only to share experiences across the country but also to integrate several resources using the New Information and Communication Technologies to support new pedagogical approaches for medical students and also for continuing medical education. The project includes: A virtual Medical Campus using secure access from several sites, The Integration of new interactive resources based on pedagogical methods, Implementation of new indexing and search engines based on medical vocabularies and ontologies, The definition of general and specific portals, the evaluation of the system for ergonomics and contents.

Computer-Assisted Instruction↗
PubMed1999

Modeling of the parenchymous vascularization and perfusion.

RATIONALE AND OBJECTIVES: The authors sought to create a realistic model of the parenchymous vascularization and perfusion. METHODS: A three-dimensional vascular model has been developed that reproduces the growth process of a vascular tree (angiogenesis). This model follows physical laws related to blood flow in vessels (Poiseuille's law), takes into account anatomic constraints, and optimizes a cost function related to the blood volume. RESULTS: Vascular trees, the ramifications of which go from main arteries to small arterioles, were simulated. Vascular structures corresponding to either a normal tissue perfusion or an abnormal perfusion (for example, a local hypervascularization) were presented in three dimensions (volume rendering). Geometric and hemodynamic characteristics computed on these trees were consistent with those of real data found in the literature. The vascular model is also a good tool for studying the propagation of the contrast product in normal and abnormal vessels. CONCLUSIONS: The three-dimensional vascular model presented in this article provides insight into the simulation and the understanding of anatomic or physiologic vascular modifications.

Blood Vessels↗