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Hiles P, Gilligan P, Damilakis J, Briers E, Candela-Juan C, Faj D, Foley S, Frija G, Granata C, de Las Heras Gala H, Pauwels R, Sans Merce M, Simantirakis G, Vano E. European consensus on patient contact shielding. Radiography (Lond) 2021; 28:353-359. [PMID: 34953726 DOI: 10.1016/j.radi.2021.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.
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Affiliation(s)
- P Hiles
- Glan Clwyd Hospital, Bodelwyddan, Denbighshire, UK.
| | - P Gilligan
- European Federation of Organizations for Medical Physics, Utrecht, the Netherlands; Mater Private Hospital, Eccles St., Dublin 7, Ireland
| | - J Damilakis
- European Society of Radiology, EuroSafe Imaging, Vienna, Austria; University of Crete, Iraklion, Crete, Greece
| | - E Briers
- Member ESR-Patient Advisory Group, Patient Advocate, Hasselt, Belgium
| | - C Candela-Juan
- European Federation of Organizations for Medical Physics, Utrecht, the Netherlands; Centro Nacional de Dosimetría (CND), Instituto Nacional de Gestión Sanitaria, Valencia, Spain
| | - D Faj
- European Radiation Dosimetry Group, Neuherberg, Germany; Faculty of Dental Medicine and Health, Osijek, Croatia
| | - S Foley
- European Federation of Radiographer Societies, Utrecht, the Netherlands; Radiography & Diagnostic Imaging, University College Dublin, Ireland
| | - G Frija
- European Society of Radiology, EuroSafe Imaging, Vienna, Austria; Université de Paris, France
| | - C Granata
- European Society of Paediatric Radiology, Le Kremlin-Bicêtre, France; Institute for Maternal and Child Health, IRCCS "Burlo Garofolo", Trieste, Italy
| | - H de Las Heras Gala
- European Federation of Organizations for Medical Physics, Utrecht, the Netherlands; Federal Office for Radiation Protection, Oberschleißheim, Germany
| | - R Pauwels
- Aarhus Institute of Advanced Studies, Aarhus University, Denmark
| | - M Sans Merce
- European Radiation Dosimetry Group, Neuherberg, Germany; Geneva University Hospitals, Geneva, Switzerland
| | - G Simantirakis
- European Radiation Dosimetry Group, Neuherberg, Germany; Greek Atomic Energy Commission, Agia Paraskevi, Athens, Greece
| | - E Vano
- European Society of Radiology, EuroSafe Imaging, Vienna, Austria; Radiology Department, Complutense University, Spain
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Fitton I, Revel MP, Burgel PR, Hernigou A, Boussaud V, Guillemain R, Le Pimpec-Barthes F, Bennani S, Freche G, Frija G, Chassagnon G. Cumulative radiation dose after lung transplantation in patients with cystic fibrosis. Diagn Interv Imaging 2019; 100:287-294. [DOI: 10.1016/j.diii.2018.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/17/2018] [Accepted: 12/20/2018] [Indexed: 12/12/2022]
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3
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Luciani A, Clement O, Halimi P, Goudot D, Portier F, Bassot V, Luciani JA, Avan P, Frija G, Bonfils P. Catheter-Related Upper Extremity Deep Venous Thrombosis in Cancer Patients: A Prospective Study Based on Doppler US. Nutr Clin Pract 2016. [DOI: 10.1177/0115426502017005324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Clément O, Faye N, Fournier L, Siauve N, Frija G. Rein et produits de contraste iodés et gadolinés. ACTA ACUST UNITED AC 2011; 92:291-8. [DOI: 10.1016/j.jradio.2011.02.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 02/24/2011] [Indexed: 10/18/2022]
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5
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Affiliation(s)
- G Frija
- HEGP, Radiolgie, 75015 Paris, France.
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Revel MP, Sanchez O, Dechoux S, Couchon S, Frija G, Cazejust J, Chatellier G, Meyer G. Contribution of indirect computed tomographic venography to the diagnosis of postpartum venous thromboembolism. J Thromb Haemost 2008; 6:1478-81. [PMID: 18627442 DOI: 10.1111/j.1538-7836.2008.03078.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The diagnostic value of indirect computed tomographic venography (CTV), following thoracic computed tomographic angiography (CTA), has not been specifically evaluated in postpartum patients with suspected pulmonary embolism. OBJECTIVES To assess the diagnostic value of CTV in postpartum venous thromboembolism. METHODS We reviewed all CTA and CTV procedures performed during the last 7 years in our institution for suspected pulmonary embolism during the postpartum period. We focused on the quality of CTA, the rates of positive CTA and isolated positive CTV findings, and alternative diagnoses provided by CTV. RESULTS Fifty-five CTA and 33 CTV procedures were performed for suspected pulmonary embolism in 47 patients referred between 24 h and 2 months after Cesarean (34 patients) or vaginal (13 patients) delivery. Of the 33 patients who had both CTA and CTV, seven had positive CTA findings and four had isolated positive CTV findings. Thus, the absolute increase in the venous thromboembolism detection rate following CTV was 12.1% [95% confidence interval (CI) 4.0-29.1]. Subcapsular hematoma of the liver or spleen was found on CTV in another two patients without venous thromboembolism. Consequently, CTV had a direct impact on clinical management in six of 33 patients (18%). CONCLUSION Our results suggest that postpartum patients with suspected pulmonary embolism have a significant rate of pelvic vein thrombosis and that the use of CTV leads to a 31% relative increase in the detection rate of venous thromboembolism as compared to CTA alone in these patients.
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Affiliation(s)
- M P Revel
- Radiology Department, Hopital Europeen Georges Pompidou, APHP, Faculte de Medicine, Universite Paris Descartes, Paris, France
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Abstract
Imaging plays a crucial role in oncology to assist in the management of patients and selection of drug regimen. Recent advances in imaging techniques allowing to predict and evaluate response to treatments in oncology will be reviewed. The standard in the evaluation of response to treatment is based on the measurement of lesion size. Functional imaging assesses physiological or molecular processes that may be earlier indicators of early response to treatment. Dynamic imaging of tumor vascularization assesses the biodistribution of a contrast agent within tumoral tissues. Diffusion-weighted MR imaging can differentiate free water from water restricted by tissues, providing an assessment of tumor cellularity. MR spectroscopy assesses the relative quantity of specific chemical components within normal and tumoral tissues. 18 FDG PET imaging provides an assessment of the metabolic activity of tissues. FDG uptake is proportional to cellular proliferation and number of viable cells within a tumor. Results from studies assessing the role of these emerging imaging techniques remain preliminary and the medical community must determine their respective role in the routine evaluation of response to treatment in oncological patients.
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Affiliation(s)
- L S Fournier
- Service de Radiologie, Hôpital Européen Georges Pompidou, 20 rue Leblanc, 75015 Paris.
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Fournier L, Thiam R, Medioni J, Trinquart L, Balvay D, Frija G, Oudard S, Cuenod CA. CMR 2007: 2.03: Can clinical DCE-CT using small molecular iodinated contrast agent detect and quantify the effect of anti-angiogenic drugs on metastatic renal cell carcinoma? Contrast Media Mol Imaging 2007. [DOI: 10.1002/cmmi.164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Fournier L, Thiam R, Cuenod C, Medioni J, Trinquart L, Balvay D, Banu E, Balcaceres J, Frija G, Oudard S. Dynamic contrast-enhanced CT (DCE-CT) as an early biomarker of response in metastatic renal cell carcinoma (mRCC) under anti-angiogenic treatment. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.14003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
14003 Background: Evaluation of treatment response for cancer relies on application of criteria based on size such RECIST. However, changes in size are often delayed and small. An accurate and early evaluation of tumor vascular characteristics would allow selection of patients (pts) who would most likely benefit of these therapies and early detection of treatment response to tailor therapy on an individual basis. Changes in tumor vascular parameters were quantified using dynamic contrast-enhanced computed tomography (DCE-CT) as a biomarker for tumor angiogenesis. Methods: A total of 44 mRCC pts were enrolled in an imaging study corollary of two phase III trials evaluating efficacy of anti-angiogenic drugs: sorafenib (N=9) vs. placebo (N=13), or sunitinib (N=17) vs. interferon (N=5). Perfusion CT acquisitions after injection of 80 ml of iodinated contrast agent were performed on a single “functional metastatic target” before treatment and every 6 weeks for follow-up. Microvascular parameters of the functional target were calculated using a dedicated software based on compartmental models: tumor blood flow (TBF) (ml/min/100g), tumor blood volume (TBV) (%), vascular permeability (VP) (ml/min/100g) and mean transit time (MTT) (s). These parameters were correlated to the best treatment response as evaluated by the size variation of the RECIST targets. Results: Among the 26 treated pts, there was a statistically significant drop in TBF and TBV as early as the first cycle of treatment (respectively -50%, p=0.03 and -51%, p<0.01) compared to pre-treatment, showing the biological effect of the drug on tumor vascularity. There was a significantly higher drop in TBF and TBV in pts who would be later classified as responders (N=16) vs. non-responders (N=10) after the first cycle of treatment (-66% vs. -6%, p=0.02; -60% vs. -26.5%, p=0.04). The changes in MTT and VP were not correlated to the best response. Conclusions: The functional imaging biomarkers TBF and TBV quantified by DCE-CT detect the biological effect of anti-angiogenic drugs on tumor vessels. TBF appears as very early predictor of mRCC response to anti-angiogenic drugs supporting the hypothesis that DCE-CT may constitute a surrogate biomarker of angiogenesis inhibition. No significant financial relationships to disclose.
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Affiliation(s)
- L. Fournier
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - R. Thiam
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - C. Cuenod
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - J. Medioni
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - L. Trinquart
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - D. Balvay
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - E. Banu
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - J. Balcaceres
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - G. Frija
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
| | - S. Oudard
- Georges Pompidou European Hospital, Paris, France; Rene Descartes Paris 5 University, Paris, France
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Abstract
Imaging in cancer plays a capital role to guide the clinician in his choice of therapies. We will discuss the new techniques available to predict and evaluate treatment response in oncology. The method of reference to evaluate treatment response is based on the measure of lesion size. Functional imaging doesn't evaluate size, but rather a physiological or molecular feature, which is probably modified earlier in response to treatment. Dynamic contrast-enhanced functional imaging of microcirculation follows the biodistribution of a contrast agent and analyses tumour vascularization. Diffusion-weighted Magnetic Resonance Imaging differentiates free and restrained water molecules in tissues, reflecting tumor cellularity. Nuclear Magnetic Resonance spectroscopy is an application of MRI that yields information on the metabolic content of a tissue. It detects relative quantities of various molecules which differ in tumour compared to normal tissue. Positon-emission tomography using (18)FDG is a nuclear medicine technique which gives information on tissue metabolism. Captation of FDG is proportional to the proliferative activity and the number of viable cells in a tumour. Human studies concerning these techniques are still quite preliminary, and the medical community must determine their potential in clinical practice to evaluate treatment response in oncology.
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Affiliation(s)
- L-S Fournier
- Service de Radiologie, Hôpital Européen Georges-Pompidou, 20, Rue Leblanc, 75015 Paris, France.
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11
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Salomon LJ, Siauve N, Taillieu F, Balvay D, Vayssettes C, Frija G, Ville Y, Cuénod CA, Clément O. In Vivo Dynamic MRI Measurement of the Noradrenaline-induced Reduction in Placental Blood Flow in Mice. Placenta 2006; 27:1007-13. [PMID: 16316684 DOI: 10.1016/j.placenta.2005.10.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Revised: 10/04/2005] [Accepted: 10/18/2005] [Indexed: 11/19/2022]
Abstract
PURPOSE We developed a new model for in vivo placental perfusion measurements based on dynamic MRI in mice. As noradrenaline has been implicated in the pathogenesis of preeclampsia, we examined whether it reduced placental perfusion in mice, and whether such a reduction could be detected with our MRI model. MATERIALS AND METHODS Mice at 16 days of gestation were injected intramuscularly with saline or noradrenaline solution. A conventional gadolinium chelate was then injected IV, and a single-slice T1-weighed 2D Fast SPGR sequence was acquired for 200 s. Signal intensity was measured on all the images and converted into contrast agent tissue concentrations in the maternal left ventricle (input function) and placentas. A one-compartment model was developed using compartmental and numerical modeling software. Mean blood flow (F) was calculated from a transfer constant. RESULTS Twenty-six mice were studied, yielding a total of 55 MRI measurements of placental perfusion (29 in the control group and 26 in the noradrenaline group). Mean placental blood flow (F) was significantly lower in the noradrenaline group (0.72+/-0.84 ml/min/g of placenta) than in the control group (1.26+/-0.54 ml/min/g of placenta). CONCLUSION Noradrenaline reduces placental perfusion in mice. Our MRI dynamic model might be useful for detecting and investigating abnormal placental blood flow, thereby avoiding the need for invasive procedures and animal sacrifice.
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Affiliation(s)
- L J Salomon
- Faculté de Médecine, Laboratoire de Recherche en Imagerie, Faculté de médecine Necker Enfants Malades, Université Paris Descartes, Paris, France.
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Frija G. [Journal de Radiologie: even more!]. J Radiol 2006; 87:7. [PMID: 16415774 DOI: 10.1016/s0221-0363(06)73963-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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13
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Salomon L, Siauve N, Taillieu F, Balvay D, Vayssettes C, Frija G, Ville Y, Cuenod C, Clement O. In vivo dynamic MRI measurement of the noradrenaline-induced reduction in placental blood flow in mice. Am J Obstet Gynecol 2005. [DOI: 10.1016/j.ajog.2005.10.626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Salomon LJ, Siauve N, Taillieu F, Balvay D, Clément O, Vayssettes C, Frija G, Ville Y, Cuénod CA. L’IRM fonctionnelle pour l’étude de la fonction placentaire. ACTA ACUST UNITED AC 2005; 34:666-73. [PMID: 16270004 DOI: 10.1016/s0368-2315(05)82899-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Placental insufficiency, a process due to either poor placental perfusion or permeability, may lead to progressive deterioration in placental function and materno-fetal morbidity. Advances in MR contrast media pharmacokinetic studies of transit through tissues and dynamic MRI allow to characterize organs microcirculation in vivo. Placental function assessment might be achieved using analysis of dynamic contrast enhanced MRI of tracers. A murine model of placental assessment has been constructed. Herein, principles, results and limitations of such techniques are discussed as well as their potential interest and weaknesses in humans.
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Affiliation(s)
- L-J Salomon
- Laboratoire de Recherche en Imagerie, Paris V, Faculté de Médecine Necker
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15
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Pradel C, Siauve N, Bruneteau G, Clement O, de Bazelaire C, Frouin F, Wedge SR, Tessier JL, Robert PH, Frija G, Cuenod CA. Reduced capillary perfusion and permeability in human tumour xenografts treated with the VEGF signalling inhibitor ZD4190: an in vivo assessment using dynamic MR imaging and macromolecular contrast media. Magn Reson Imaging 2003; 21:845-51. [PMID: 14599534 DOI: 10.1016/s0730-725x(03)00186-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We describe the use of perfusion-permeability magnetic resonance imaging (ppMRI) to study hemodynamic parameters in human prostate tumor xenografts, following treatment with the vascular endothelial growth factor-A (VEGF) receptor tyrosine kinase inhibitor, ZD4190. Using a macromolecular contrast agent (P792), a fast MR imaging protocol and a compartmental data analysis, we were able to demonstrate a significant simultaneous reduction in tumor vascular permeability, tumor vascular volume and tumor blood flow (43%, 30% and 42%, respectively) following ZD4190 treatment (100 mg/kg orally, 24 h and 2 h prior to imaging). This study indicates that MR imaging can be used to measure multiple hemodynamic parameters in tumors, and that tumor vascular permeability, volume and flow, can change in response to acute treatment with a VEGF signaling inhibitor.
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Affiliation(s)
- C Pradel
- Laboratoire de Recherche en Imagerie, LRI-U494, Faculte Necker, Paris, France
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Cuenod CA, de Parades V, Siauve N, Marteau P, Grataloup C, Hernigou A, Berger A, Cugnenc PH, Frija G. [MR imaging of ano-perineal suppurations]. J Radiol 2003; 84:516-28. [PMID: 12844075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
A good digital examination is usually sufficient for the diagnosis and the treatment planning of anal fistulae. Cross-sectional imaging techniques, however, can accurately identify deep abscesses and characterize complex fistulae. MRI is well suited for this examination, with almost no motion artifact, excellent contrast between muscles and fatty spaces, and multiplanar acquisition. A fistula starts from an internal opening in the digestive tube and can end in an abscess cavity or open at the skin at an external opening. The cryptoglandular anal fistulae (fistula-in-ano) are non-specific in origin and are usually simple, whereas specific fistulae are due to many diseases such as Crohn's disease, tuberculosis, trauma, radiation, colloid carcinoma, hidradenitis suppurative, actinomycosis or lymphoma and are often complex. MRI appears useful in the cases with recurrent fistulae, Crohn's disease, when the secondary orifice is atypically placed, during a multistep treatment for complex fistulae, or when an anal stenosis forbids a clinical or ultrasound examination. A good knowledge of the perineum anatomy is required for analysing the fistula tracts. The muscle planes separate fatty spaces which have an important role in the spread of the disease: sub-mucosal space, marginal space, intersphincteric space, postanal space of Courtney, supralevator space, and the two ischioanal spaces on both sides of the anal canal. The anal canal is surrounded by the ring-like internal sphincter, which continues the internal muscularis propria of the rectum, and the external sphincter, which is intermingled with the puborectalis muscle. We perform our MRI examination with an external phased array coil, and we place a cannula to identify the anal canal. The T2W sequences give the more interesting information, but the sequences with fat-suppression and gadolinium chelate injection are also very useful. The MRI examination allows the analysis of: 1) the location of the fistula tracts according to Park's classification, 2) the location of the internal opening, 3) the locations of the external opening(s), 4) the location of deep abscesses, 5) the long distance extensions, 6) the state of the ano-rectal wall and the perirectal spaces, 6) the damages of the anal sphincter.
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Affiliation(s)
- C A Cuenod
- Service de Radiologie, Hôpital Européen Georges Pompidou, 20 rue Leblanc, 75015 Paris.
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Kahn E, Tessier C, Lizard G, Petiet A, Bernengo JC, Coulaud D, Fourré C, Frouin F, Clément O, Jourdain JR, Delain E, Guiraud-Vitaux F, Colas-Linhart N, Siauve N, Cuenod CA, Frija G, Todd-Pokropek A. Analysis of the distribution of MRI contrast agents in the livers of small animals by means of complementary microscopies. Cytometry A 2003; 51:97-106. [PMID: 12541284 DOI: 10.1002/cyto.a.10017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Magnetic resonance imaging (MRI) contrast agents contain magnetic molecules such as iron (Fe) or gadolinium (Gd) that are injected in vivo into rats or mice to study their distribution inside the liver. Fluorescent europium (Eu) can be used as a model of Gd to obtain comparable information of this distribution of corresponding contrast agents. In a similar approach, Fe can be attached to Texas Red and used as a model of ferumoxides and be detected by fluorescence. METHODS To combine and compare the advantages of different microscopic imaging modes, characterization studies were carried out by means of a confocal laser scanning microscope (CLSM), a secondary ion mass spectrometric (SIMS) microscope, and an electron energy loss spectrometric (EELS) microscope. In the case of CLSM, the locations of fluorescent signals inside preparations were determined by factor analysis of biomedical image sequences (FAMIS) and selection of image sequences at emission. RESULTS By CLSM and FAMIS, we distinguished chelated Eu and Texas Red attached to Fe. By SIMS microscopy, we distinguished Eu and Gd of chlorides and chelates and Fe of a ferumoxide. By EELS microscopy, we distinguished Eu and Gd of chlorides. CONCLUSIONS Analysis of compounds inside correlative specimens by means of CLSM, SIMS, and EELS microscopes provided complementary results.
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Affiliation(s)
- E Kahn
- INSERM U494, CHU Pitié-Salpétrière, 75634 Paris Cedex 13, France.
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Frija G. [Elias A. Zerhouni: a radiologist head of the NIH]. J Radiol 2002; 83:598. [PMID: 12063421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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Bely-Toueg N, Halimi P, Laccourreye O, Laskri F, Brasnu D, Frija G. Normal laryngeal CT findings after supracricoid partial laryngectomy. AJNR Am J Neuroradiol 2001; 22:1872-80. [PMID: 11733319 PMCID: PMC7973841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
BACKGROUND AND PURPOSE Supracricoid horizontal partial laryngectomy (SCPL) is increasingly used to treat endolaryngeal carcinoma. However, few radiologic reports of these procedures exist. Our purpose was to evaluate the normal CT appearance of the neolarynx after surgery. METHODS SCPL includes cricohyoidopexy (CHP), cricohyoidoepiglottopexy (CHEP), and tracheocricohyoidoepiglottopexy (TCHEP). We examined CT scans obtained from 18 patients without local superficial recurrence who underwent SCPL: 10, CHEP; seven, CHP; and one, TCHEP. Three reference sections were used to analyze the main surgical reconstruction: an upper section through the hyoid bone, a lower section through the cricoid cartilage, and a middle section in between. The distance between the hyoid bone and cricoid cartilage was measured. RESULTS The epiglottis and valleculae were visible in the upper section in seven of 10 patients who underwent CHEP; this finding allowed distinction between CHEP and CHP. The arytenoids were depicted in 13 of 18 cases and reflected neolaryngeal shortening. The lower section showed the empty cricoid lumen lined by a thin mucosa; the anterior arch of the cricoid was amputated at TCHEP. The middle section showed the neovestibule, the lateral boundaries of which were the hypertrophic neoaryepiglottic folds; the anterior limit was the epiglottis for CHEP or the base of the tongue for CHP. The average distance between the hyoid bone and cricoid cartilage was 11 mm. CONCLUSION Normal CT anatomy of the larynx after SCPL is defined. Three key sections may accurately distinguish the various types of SCPL. CT is a valuable tool for depicting tumor recurrence, especially when the tumor is submucosal.
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Affiliation(s)
- N Bely-Toueg
- Departments of Radiology, Hospital Laennec, University of Paris, France
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Luciani A, Clement O, Halimi P, Goudot D, Portier F, Bassot V, Luciani JA, Avan P, Frija G, Bonfils P. Catheter-related upper extremity deep venous thrombosis in cancer patients: a prospective study based on Doppler US. Radiology 2001; 220:655-60. [PMID: 11526263 DOI: 10.1148/radiol.2203001181] [Citation(s) in RCA: 178] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE This prospective study extending for more than 3 years had two objectives: (a) to use Doppler ultrasonography (US) to estimate the incidence of asymptomatic catheter-related upper extremity deep venous thrombosis (DVT) in a large population and (b) to study the effect of the catheter position as an individual risk factor for catheter-related DVT. MATERIALS AND METHODS Between October 1995 and June 1998, a total of 145 patients who had oropharyngeal tract cancer and who were fitted with the same totally implantable central venous catheters (CVCs) were included in the study. Follow-up included (a) estimation of the position of each catheter tip on a chest radiograph obtained immediately after surgery and (b) regular monthly Doppler US screening for catheter-related DVT. RESULTS Seventeen patients developed catheter-related DVT; 13 of them were asymptomatic. The mean interval between CVC implantation and detection of thrombosis was 42.2 days. Correct positioning of the distal catheter tip was associated with a significantly lower rate of catheter-related DVT. Only five of 87 patients with a correctly positioned distal catheter tip (ie, either in the superior vena cava or at the junction between the right atrium and the superior vena cava) developed thrombosis, compared with 12 of 26 patients with a misplaced catheter (P <.001). The side on which the CVC was implanted did not influence the catheter-related DVT rate. CONCLUSION The rate of asymptomatic catheter-related DVT is high and could be lowered with correct initial CVC positioning.
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Affiliation(s)
- A Luciani
- Department of Radiology, Hôpital Européen Georges Pompidou, 20 rue Leblanc, 75908 Paris Cedex 15, France
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Kahn E, Lizard G, Frouin F, Souchier C, Bernengo JC, Siitari H, Cuenod CA, Clément O, Frija G, Gambert P, Todd-Pokropek A. Confocal image characterization of human papillomavirus DNA sequences revealed with Eu in HeLa cell nuclei stained with Hoechst 33342. Anal Quant Cytol Histol 2001; 23:101-8. [PMID: 11332075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To visualize and localize specific viral DNA sequences revealed with Eu by fluorescence in situ hybridization, confocal laser scanning microscopy (CLSM) and factor analysis of biomedical image sequences (FAMIS). STUDY DESIGN Human papillomavirus DNA (HPV-DNA) was identified in HeLa cells with biotinylated DNA probes recognizing HPV-DNA types 16/18. DNA-DNA hybrids were revealed by a three-step immunohistochemical amplification procedure involving an antibiotin mouse monoclonal antibody, a biotinylated goat antimouse polyclonal antibody and streptavidin-Eu. Cell nuclei were counterstained with Hoechst 33342. Image sequences were obtained using a CLSM that made possible ultraviolet excitation. The location of fluorescent signals inside cellular preparations was determined by FAMIS and selection of filters at emission. Image sequences were summarized into a reduced number of images, or factor images, and curves, or factors. Factors estimate spectral or temporal patterns and depth emission profiles. Factor images correspond to spatial distributions of the different factors. RESULTS We distinguished between Eu corresponding to HPV-DNA hybridization signals and nuclear staining by taking into account differences in their spectral and temporal patterns and (using their decay rates). CONCLUSION FAMIS, together with CLSM and Eu, made possible the detection and characterization of viral papillomavirus DNA sequences in HeLa cells.
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Affiliation(s)
- E Kahn
- Institut National de la Santé et de la Recherche Médicale U494, Centre Hospitalier Universitaire Pitié-Salpêtrière, 91 boulevard de l'Hôpital, 75634 Paris, France.
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22
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Cuenod C, Leconte I, Siauve N, Resten A, Dromain C, Poulet B, Frouin F, Clément O, Frija G. Early changes in liver perfusion caused by occult metastases in rats: detection with quantitative CT. Radiology 2001; 218:556-61. [PMID: 11161178 DOI: 10.1148/radiology.218.2.r01fe10556] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE To determine whether computed tomography (CT) can depict liver hemodynamic changes caused by occult hepatic micrometastases in rat. MATERIALS AND METHODS Liver micrometastases (mean diameter, 500 micrometer +/- 300) were produced in seven BD IX rats by injecting 10(7) DHDK12 PROb colorectal carcinoma cells into the spleen. Macrometastases (mean diameter, 7 mm +/- 3) were produced in four other rats. Five normal rats were studied as controls. CT images were obtained every 300 msec for 30 seconds during the injection of 1 mL per kilogram of body weight of contrast medium. The time-attenuation curves of the aorta, portal vein, and liver were used to calculate liver perfusion with a deconvolution model designed for the dual blood supply. RESULTS Micrometastases in an apparently normal liver caused a 34% decrease in portal blood flow and a 25% increase in the mean transit time for the blood to pass through the liver. These findings suggest increased resistance in the sinusoidal capillaries. Similar but greater changes were found in the macrometastases. CONCLUSION Occult liver micrometastases in rats generate changes in liver perfusion that can be detected with CT.
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Affiliation(s)
- C Cuenod
- Institut National de la Santé et de la Recherche Médicale (INSERM) U494, Paris, France.
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23
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Kahn E, Lizard G, Frouin F, Bernengo JC, Souchier C, Bessède G, Clément O, Siitari H, Gambert P, Frija G, Todd-Pokropek A. Confocal analysis of phosphatidylserine externalization with the use of biotinylated annexin V revealed with streptavidin-FITC, -europium, -phycoerythrin or -Texas Red in oxysterol-treated apoptotic cells. Anal Quant Cytol Histol 2001; 23:47-55. [PMID: 11233743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVE To analyze externalization of phosphatidylserine via annexin V on apoptotic cells by laser scanning confocal microscopy and factor analysis of biomedical image sequences (FAMIS). STUDY DESIGN Streptavidin-fluorescein isothiocyanate (FITC), -europium (Eu), -phycoerythrin (PE) and -Texas Red (TR) were chosen to reveal the binding of biotinylated annexin V on apoptotic U937 human leukemic cells and ECV-304 human endothelial cells induced under treatment with 7-ketocholesterol or 7 beta-hydroxycholesterol. Excitation of each fluorochrome was obtained by selection of specific lines (351 + 364 nm, 488 nm) of the argon laser of a confocal microscope. Temporal and spectral series were performed to characterize each fluorochrome. FAMIS was applied to these series to estimate images corresponding to stains. RESULTS Each fluorochrome was clearly distinguished, and images showed localization of phosphatidylserine, which was improved by image analysis. CONCLUSION On apoptotic cells it is possible to analyze differences in the improved visualization of phosphatidylserine in series processed by FAMIS with the use of biotinylated annexin V revealed with streptavidin-FITC, -Eu, -PE or -TR.
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Affiliation(s)
- E Kahn
- Institut National de la Santé et de la Recherche Médicale U494, Centre Hospitalier Universitaire Pitié-Salpêtrière, 75634 Paris, France.
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Lewin M, Clément O, Belguise-Valladier P, Tran L, Cuénod CA, Siauve N, Frija G. Hepatocyte targeting with Gd-EOB-DTPA: potential application for gene therapy. Invest Radiol 2001; 36:9-14. [PMID: 11176256 DOI: 10.1097/00004424-200101000-00002] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
RATIONALE AND OBJECTIVES To evaluate the suitability of the liver-specific MRI contrast agent Gd-EOB-DTPA as a nonviral vector for gene therapy of hepatocellular carcinoma. METHODS Specific uptake of Gd-EOB-DTPA was quantified by relaxometry in rat cultured hepatocytes and the hepatoma cells HepG2 and Huh7. Nonviral vectors for gene transfer were synthesized by coupling Gd-EOB-DTPA to polyethyleneimine or polylysine as DNA condensing agents, and their efficiency was studied using beta-galactosidase (lacZ) as the reporter gene. RESULTS Gd-EOB-DTPA was specifically taken up by rat cultured hepatocytes (4.32 vs. 1.08 mmol/L in nonhepatocyte control cells) but not by the hepatoma cells; this uptake was concentration-dependently inhibited by Bromsulphtalein. Polycation linkages were achieved with yields of 0.9 Gd-EOB-DTPA molecule per polyethyleneimine molecule and 10 Gd-EOB-DTPA molecules per polylysine molecule. Incubating the cells with plasmids containing lacZ reporter gene and polyethyleneimine-Gd-EOB-DTPA resulted in a few blue (transfected) cells, whereas no blue cells were observed on incubation with polylysine-Gd-EOB-DTPA. CONCLUSIONS Gd-EOB-DTPA is taken up by normal hepatocytes but not by HepG2 and Huh7 cells, probably because of the lack of the organic anion transporter in these hepatoma cells. The Gd-EOB-DTPA polycation conjugates, such as polyethyleneimine-Gd-EOB-DTPA, could serve as transfer vectors of interest for gene targeting imagery at the early stage of hepatocarcinogenesis. However, the transfer efficiency of such conjugates is low and requires improvement.
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Affiliation(s)
- M Lewin
- Laboratoire d'Imagerie, Unité Inserm 494, Faculty of Medecine Necker, Paris, France
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Réty F, Clément O, Siauve N, Cuénod CA, Carnot F, Sich M, Buisine A, Frija G. MR lymphography using iron oxide nanoparticles in rats: pharmacokinetics in the lymphatic system after intravenous injection. J Magn Reson Imaging 2000; 12:734-9. [PMID: 11050643 DOI: 10.1002/1522-2586(200011)12:5<734::aid-jmri10>3.0.co;2-r] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The objective of the study was to quantify the kinetics of the superparamagnetic nanoparticle ferumoxtran (AMI 227, Sinerem(R), Combidex(R)) in the efferent lymph of the subdiaphragmatic lymph nodes and in various node groups of the rat to elucidate the uptake mechanism. The thoracic lymph duct was catheterized in 24 rats after an IV injection of 40 micromol Fe/kg ferumoxtran. Three rats were studied at several time points between 1.5 and 24 hours. At each time point, 0.3 ml of lymph were collected over 45 minutes. Lymph nodes were differentiated into five groups. The iron concentration in the samples and in plasma was measured by relaxometry at 0.47 T and atomic absorption spectrometry. Cytology was performed on the lymph. High concentrations of nanoparticles were found in the thoracic lymph soon after injection (90 minutes). No particle was found in the lymph cells, indicating that ferumoxtran was extracellular in the lymph fluid. The maximum concentration was reached later in all node groups, at 12 hours, and then plateaued. The transcapillary pathway and subsequent lymph drainage of the particles seem to play a major role in the delivery to the lymph nodes.
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Affiliation(s)
- F Réty
- Laboratoire de Recherche en Imagerie, INSERM U 494, School of Medicine Necker Enfants-Malades, 75015 Paris, France
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Kahn E, Frouin F, Souchier C, Bernengo JC, Bruzzoni-Giovanelli H, Clément O, Frija G, Di Paola R, Calvo F, Linares-Cruz G. Confocal multilaser focusing and single-laser characterization of ultraviolet excitable stains of cellular preparations. Cytometry 2000; 40:42-9. [PMID: 10754516 DOI: 10.1002/(sici)1097-0320(20000501)40:1<42::aid-cyto6>3.0.co;2-t] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The aims of this study were (1) to realign cellular preparations when spots and structures are excited by different lasers of a confocal laser scanning microscope (multilaser studies); (2) to avoid the use of realigment methods by selecting fluorochromes that can be excited by only one laser (single-laser experiments). METHODS In multilaser studies, we used propidium iodide fluorescent beads, as well as tetramethyl rhodamine isothiocyanate (TRITC), fluorescein isothiocyanate (FITC), and 4'-6 diamidino-2-phenylindole (DAPI)-stained human cancer lines. They were excited using HeNe, argon, and ultraviolet (UV) argon laser lines of a confocal laser scanning microscope. Single-laser experiments using UV excitation only were performed using europium as a model for magnetic resonance paramagnetic contrast agents. Nuclei of human cancer lines and tissue were counterstained by DAPI and cytoplasms were labeled with ELF-97 substrates. Factor analysis of medical images (FAMIS) and correlation methods were used to realign shifted images, focus images, and characterize each fluorochrome when necessary. RESULTS In multilaser studies, superimposition of factor images corrected Z shifts and correlation methods provided X, Y correction values. In single-laser experiments, each fluorochrome was clearly distinguished in the group of fluorochromes. Estimated images in both studies showed colocalizations of structures. CONCLUSIONS It is possible to characterize differences in the focus and alignment of fluorescent probes and to correct them. It is also possible to study colocalization of UV excitable fluorochromes (DAPI, ELF-97, europium) in cellular and tissular preparations via multilaser or single-laser experiments.
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Affiliation(s)
- E Kahn
- INSERM U494, CHU Pitié-Salpêtrière, Paris, France.
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27
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Clément O, Siauve N, Cuénod CA, Vuillemin-Bodaghi V, Leconte I, Frija G. Mechanisms of action of liver contrast agents: impact for clinical use. J Comput Assist Tomogr 1999; 23 Suppl 1:S45-52. [PMID: 10608397 DOI: 10.1097/00004728-199911001-00007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
New contrast agents for magnetic resonance imaging are continually being developed by pharmaceutical companies in order to better image the liver. These agents can be divided into hepatobiliary agents directed to the hepatocytes and nanoparticulate agents directed to the reticulo-endothelial system. After intravenous injection, all these agents concentrate in the liver and induce profound changes in signal intensity. Particulate agents induce predominantly a darkening of the liver parenchyma, while hepatobiliary agents induce a brightening. In both cases, liver-lesion conspicuity is enhanced, leading to a better visualization of the lesion. After a brief description of the principal characteristics of the agents, this paper will attempt to summarize the utility of these agents for the detection and characterization of focal liver disease.
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Affiliation(s)
- O Clément
- Service de Radiologie, Hôpital Boucicaut-Laënnec, Paris, France.
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28
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Cuénod CA, Wind P, Siauve N, Clément O, Bénichou J, Frija G. [Emergency diagnosis of acute digestive tract abdominal pain in adults. Contribution of imaging]. Gastroenterol Clin Biol 1999; 23:1170-86. [PMID: 10617824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Affiliation(s)
- C A Cuénod
- Service de Radiologie, Hôpital Laennec, 75340 Paris Cedex 07.
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29
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Amiel M, Sigal R, Frija G. [Teleradiology]. J Radiol 1999; 80:899. [PMID: 11048541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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30
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Qanadli SD, Orvoen-Frija E, Lacombe P, Di Paola R, Bittoun J, Frija G. Estimation of gas and tissue lung volumes by MRI: functional approach of lung imaging. J Comput Assist Tomogr 1999; 23:743-8. [PMID: 10524859 DOI: 10.1097/00004728-199909000-00020] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The purpose of this work was to assess the accuracy of MRI for the determination of lung gas and tissue volumes. METHOD Fifteen healthy subjects underwent MRI of the thorax and pulmonary function tests [vital capacity (VC) and total lung capacity (TLC)] in the supine position. MR examinations were performed at inspiration and expiration. Lung volumes were measured by a previously validated technique on phantoms. Both individual and total lung volumes and capacities were calculated. MRI total vital capacity (VC(MRI)) was compared with spirometric vital capacity (VC(SP)). Capacities were correlated to lung volumes. Tissue volume (V(T)) was estimated as the difference between the total lung volume at full inspiration and the TLC. RESULTS No significant difference was seen between VC(MRI) and VC(SP). Individual capacities were well correlated (r = 0.9) to static volume at full inspiration. The V(T) was estimated to be 836+/-393 ml. CONCLUSION This preliminary study demonstrates that MRI can accurately estimate lung gas and tissue volumes. The proposed approach appears well suited for functional imaging of the lung.
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Affiliation(s)
- S D Qanadli
- Department of Radiology, University René Descartes-Paris V, Ambroise Paré Hospital, Boulogne, France
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Abstract
Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the rete mirabile of the eel. The rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D<MW<900,000 D)--was characterized by reference to radioactive tracers (3HHO, 22Na, 14C-sucrose, 125I-albumin) by two parameters. These parameters were the concentration ratio of the venous output over the arterial input [C(VOUT)(%)] and the permeability coefficient (P). The transcapillary pathway mechanisms for carboxymethyldextran-Gd-DTPA and albumin-Gd-DTPA were studied by electron microscopy. P values for Gd-DOTA (9.4+/-3.6 x 10(-7) cm/s) and albumin-Gd-DTPA (11.8+/-5.5 x 10(-7) cm/s) were close to P values for 14C-sucrose, while P values for carboxymethyldextran-Gd-DTPA (6.4+/-4.9 x 10(-7) cm/sec) were similar to P values for 125I-albumin. The lowest permeability was observed with AMI-227 (2.7+/-2 x 10(-7) cm/sec). Vesicular transport was demonstrated for carboxymethyldextran-Gd-DTPA and albumin-Gd-DTPA. The transcapillary passage of several MR contrast agents can be characterized with the rete mirabile model. Molecular weight is the major factor influencing transport.
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Affiliation(s)
- N Siauve
- Laboratoire de Recherche en Imagerie, Faculté de Médecine Necker, Paris, France
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32
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Halimi P, Bely N, Chevallier JM, Bernier P, Frija G. [Radio-anatomy of the oropharynx]. J Radiol 1999; 80:223-32. [PMID: 10209719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Affiliation(s)
- P Halimi
- Servide de Radiologie, Hôpital Laennec, Paris
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Clément O, Siauve N, Lewin M, de Kerviler E, Cuénod CA, Frija G. Contrast agents in magnetic resonance imaging of the liver: present and future. Biomed Pharmacother 1998; 52:51-8. [PMID: 9755795 DOI: 10.1016/s0753-3322(98)80003-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
New contrast agents are being developed by drug companies to better image the liver magnetic resonance imaging (MRI). They can be divided into hepatobiliary agents (Gd-EOB-DTPA, Gd-BOPTA, Mangafodipir) and nanoparticulate agents directed to the reticulo-endothelial system (ferumoxides, SHU 555A). After intravenous injection, all these agents concentrate in the liver and induce profound signal changes. Particulate agents induce predominantly a darkening of the liver parenchyma, while hepatobiliary agents induce a brightening. In both cases, liver-lesion conspicuity is enhanced, leading to a better visualization of the lesion. After a description of the principal pharmacokinetic characteristics of the compounds, this review paper summarizes the utility of the agents in the detection and characterization of focal liver diseases.
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Affiliation(s)
- O Clément
- Service de Radiologie, Hôpital Laënnec, Paris, France
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34
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Clément O, Siauve N, Cuénod CA, Frija G. Liver imaging with ferumoxides (Feridex): fundamentals, controversies, and practical aspects. Top Magn Reson Imaging 1998; 9:167-82. [PMID: 9621405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Superparamagnetic nanoparticles (Feridex) have been recently made available to the radiological community as a contrast agent for MR imaging of the liver. This article reviews the principal physicochemical characteristics of this new compound, with an emphasis on the explanation of the contrast obtained (either positive or negative enhancement) that depends on the local concentration and the sequence used. The clinical use of Feridex is detailed, both for lesion detection and characterization. Finally, some guidelines for image optimization are given.
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Affiliation(s)
- O Clément
- Service de Radiologie, Hôpital Laënnec, Paris, France
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35
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Clement O, Rety F, Cuenod CA, Siauve N, Carnot F, Bordat C, Siche M, Frija G. MR lymphography: evidence of extravasation of superparamagnetic nanoparticles into the lymph. Acad Radiol 1998; 5 Suppl 1:S170-2; discussion S183-4. [PMID: 9561073 DOI: 10.1016/s1076-6332(98)80096-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- O Clement
- Laboratoire de Recherche en Imagerie, Faculté de Médecine Necker, France
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36
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de Kerviler E, Cuenod CA, Clément O, Halimi P, Frija G, Frija J. [What is bright on T1 MRI scans?]. J Radiol 1998; 79:117-26. [PMID: 9757228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
The list of entities associated with a high signal intensity on T1-weighted images is extensive and classically includes fat, proteins, hemorrhage, melanin and gadolinium. However, additional entities may be responsible for abnormally high signal intensity on T1-weighted images. These include ion deposition in metabolic disorders, free radicals, increased proton density, flow phenomena, some artifacts, and new contrast agents. The aim of this article is to display both the common and uncommon causes for a high T1 signal intensity and to discuss the underlying mechanisms or attributable pathophysiology for this phenomenon.
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Cellier C, Cuenod CA, Deslandes P, Auroux J, Landi B, Siauve N, Barbier JP, Frija G. Symptomatic hepatic cysts: treatment with single-shot injection of minocycline hydrochloride. Radiology 1998; 206:205-9. [PMID: 9423674 DOI: 10.1148/radiology.206.1.9423674] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE To assess the efficacy of percutaneous minocycline hydrochloride sclerotherapy in symptomatic hepatic cysts. MATERIALS AND METHODS From November 1992 to June 1994, seven of eight consecutive adults with large symptomatic hepatic cysts (diameter, 55-130 mm) were treated with a single intracystic injection of minocycline hydrochloride in an ambulatory procedure. Five patients had a solitary cyst, and two had polycystic liver disease. The target cyst was punctured under ultrasound guidance and local anesthesia with a 22-gauge Chiba needle. Half of the cyst content was aspirated before injection of 100-500 mg of minocycline hydrochloride diluted in 5-25 mL of saline. The minocycline hydrochloride was left in the cyst at the end of the procedure. RESULTS After a mean follow-up of 28 months (range, 24-42 months), all five patients with solitary cysts were asymptomatic and four had documented complete cyst regression; the two patients with multiple hepatic cysts showed only transient clinical improvement. CONCLUSION Single-shot injection of minocycline hydrochloride is an effective treatment for symptomatic solitary hepatic cysts but is less effective in polycystic liver disease.
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Affiliation(s)
- C Cellier
- Department of Gastroenterology, Université René Descartes, Hôpital Laennec, Paris, France
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Nseif M, Berger A, Bely N, Zinzindohoue F, Cellier C, Frija G, Cugnenc P. [False radiologic pneumoperitoneum. The value of emergency abdominal computed tomography]. J Chir (Paris) 1997; 134:329-31. [PMID: 9773000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We report 2 cases of false pneumoperitoneum. The diagnosis was suspected on an upright chest or abdominal plain films. The absence of clinical signs and symptoms of peritoneal irritation suggested a wrong radiological diagnosis. Emergency CT scan definitely eliminated a pneumoperitoneum and suggested the right diagnosis in both cases. This exam may play the decisive role in preventing needless emergency laparotomy.
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Affiliation(s)
- M Nseif
- Service de Chirurgie digestive, oncologique et générale, Hôpital Laennec, Paris
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Oswald P, Clement O, Chambon C, Schouman-Claeys E, Frija G. Liver positive enhancement after injection of superparamagnetic nanoparticles: respective role of circulating and uptaken particles. Magn Reson Imaging 1997; 15:1025-31. [PMID: 9364948 DOI: 10.1016/s0730-725x(97)00004-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Superparamagnetic nanoparticles have both high r1 and r2 relaxivities responsible for positive or negative enhancement properties. The aim of this study was to investigate to what extent perfusion (circulating particles) and uptake (clustered particles) mechanisms contribute to liver positive or negative enhancement using two different particles, superparamagnetic iron oxides (ferumoxides, AMI 25) and ultrasmall superparamagnetic iron oxides (ferumoxtran, AMI-227). Uptake kinetics were studied after intravenous injection of 20 micromol Fe/kg ferumoxtran on a washout liver model. Livers of 82 rats were surgically isolated and washed with saline infusion. Imaging was performed ex vivo at 0.5T with T1- and T2-weighted sequences. Enhancement kinetics of the liver were studied in vivo using MRI up to 180 min post injection of 20 micromol Fe/kg ferumoxtran (time response study) or 10, 20, 40 micromol Fe/kg ferumoxtran and 20 micromol Fe/kg ferumoxides (dose response study.) Particle uptake occurred early and resulted in a negative enhancement of the washed livers 15 min after injection of both T1 and T2 sequences. In vivo, a positive enhancement was only seen during the first five min with the lowest dose of ultrasmall superparamagnetic iron oxides and the T1 sequence. Uptake and clustering of the particles induced a negative liver enhancement. During the first minutes after injection, when uptake has not significantly occurred, perfusion imaging of the liver at a dose of 10 micromol Fe/kg results in a positive enhancement with T1-weighted sequences.
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Affiliation(s)
- P Oswald
- Laboratoire de Recherche en Imagerie, Faculté de Médecine Necker Enfants-Malades, Paris, France
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Randoux B, Goudot D, Clément O, Deux JF, Lecuru F, Taurelle R, Frija G. [Pseudotumor aspect of ovarian vein thrombosis]. J Radiol 1997; 78:1171-3. [PMID: 9499957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ovarian vein thrombosis is an unusual puerperal illness (1 in 600 deliveries) which usually recovers spontaneously or under treatment. We report a rare follow-up observation of a puerperal ovarian vein thrombophlebitis, first diagnosed by computed tomography, which evolved to a 6 x 10 cm pseudotumoral cavernoma mass after 18 months.
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Affiliation(s)
- B Randoux
- Service d'Imagerie Médicale, Hôpital Boucicaut, Paris
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Affiliation(s)
- S D Qanadli
- Department of Radiology, Ambroise Paré Hospital, Boulogne, France
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Abstract
Rhombencephalitis due to Listeria monocytogenes is a frequent complication of human listeriosis, inducing a high mortality and severe neurological sequelae despite antibiotic therapy. However, there is no animal model which consistently reproduces clinical rhombencephalitis. Here, we present a model of Listeria rhombencephalitis in gerbils. Animals were inoculated in the middle ears with a low infective dose of L. monocytogenes, thus creating prolonged otitis media with persistent bacteremia. Gerbils developed a severe rhombencephalitis with circling syndrome, paresia, ataxia, rolling movements. The invasion of the central nervous system was visualized on living animals by resonance magnetic imaging and characterized by bacterial growth in the brain, reaching about 10(7) bacteria in the rhombencephalum by day 12 of infection. The histological lesions were mainly located in the brainstem, and consisted in coalescent, necrotic abscesses with perivascular sheaths, mimicking those observed in human rhombencephalitis. Bacteria were detected by electronmicroscopy inside infectious foci, either free in necrotic material or inside inflammatory cells, mainly polymorphonuclear cells. This gerbil model of Listeria rhombencephalitis will be useful to study the molecular mechanisms allowing bacteria to cross the blood-brain barrier, and to evaluate the intracerebral efficacy of antibiotics.
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Affiliation(s)
- S Blanot
- INSERM U411, Faculté de Médecine Necker-Enfants Malades, Paris, France
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Blustajn J, Cuenod CA, Clement O, Siauve N, Vuillemin-Bodaghi V, Frija G. Measurement of liver blood volume using a macromolecular MRI contrast agent at equilibrium. Magn Reson Imaging 1997; 15:415-21. [PMID: 9223042 DOI: 10.1016/s0730-725x(96)00379-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Liver regional blood volume (LRBV) is altered by several disease states and various drugs. Preliminary studies in the rat, using research MR imaging instruments at 2T and vascular contrast agents, have suggested that MRI may be used to measure LRBV. Our goal was to develop a technique for measuring LRBV using a clinical machine at 1.5 T. This study was performed in the rabbit, using CarboxyMethylDextran Gd-DTPA, a macromolecular contrast agent with a molecular weight of 158 kDa. MRI was performed at 1.5 T, in the plane of the inferior vena cava, with and without flow compensation, before contrast injection and in the steady state after injection. Accuracy and stability of LRBV measurement, over 2 h and with various doses (0.01-0.05 mmol/kg), was tested against a standard Evan's Blue dye-indicator technique. LRBV was 28 +/- 2 mL/100 g when measured by MRI with flow compensation, which is in good agreement with the literature and with the 26 +/- 6 mL/100 g, measured by the Evan's Blue dilution technique. Measurements varied less than 7% over time and less than 9% over the range of doses. LRBV was overestimated using a sequence without flow compensation especially when large doses of contrast agent were injected. This noninvasive MRI technique provides a simple method for measuring liver LRBV and offers new prospects for future physiological and pathological studies.
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Affiliation(s)
- J Blustajn
- Laboratoire de Recherche en Imagerie, Faculté Necker-Enfants Malades, Paris, France
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44
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Frija G, Clément O, Le Guen O, Cuénod CA, Siauve N, Benderbous S. Experimental investigation of the delivery pathway of ultrasmall superparamagnetic iron oxide to lymph nodes. Acad Radiol 1996; 3 Suppl 2:S299-300. [PMID: 8796586 DOI: 10.1016/s1076-6332(96)80563-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- G Frija
- Laboratoire de Recherche en Imagerie, Faculté de Médecine Necker, Paris, France
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Clément O, Vuillemin-Bodaghi V, Cuénod CA, Siauve N, Blustajn J, Frija G. Quantification of liver capillary permeability using a macromolecular contrast agent for magnetic resonance imaging. Acad Radiol 1996; 3 Suppl 2:S342-3. [PMID: 8796598 DOI: 10.1016/s1076-6332(96)80578-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- O Clément
- Laboratoire de Recherche en Imagerie, Faculté de Médecine Necker, Paris, France
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Frija G, Lhoste JM, Grisoni J. A new approach to the control of distribution of medical imaging equipment in France. The Scientific Committee. Acad Radiol 1996; 3 Suppl 1:S97-100. [PMID: 8796528 DOI: 10.1016/s1076-6332(96)80498-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- G Frija
- Service de Radiologie, Hôpital Laennec, Paris, France
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47
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Siauve N, Clément O, Cuénod CA, Benderbous S, Frija G. Capillary leakage of a macromolecular MRI agent, carboxymethyldextran-Gd-DTPA, in the liver: pharmacokinetics and imaging implications. Magn Reson Imaging 1996; 14:381-90. [PMID: 8782176 DOI: 10.1016/0730-725x(96)00020-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Capillary leakage of a macromolecular contrast agent, Carboxymethyl Dextran-Gd-DTPA (CMD-Gd-DTPA) was characterized in a highly permeable system, the liver, to assess its potential as a blood pool marker. Its elimination kinetics in hepatic lymph were compared in nephrectomized rabbits with that of a tracer of extra cellular fluid space, Gd-DOTA. Four parameters were defined: volume of distribution, normalized initial leakage rate (ILRn), maximum ratio of lymph and plasma concentrations (max Cl/Cp), and the time to obtain this maximum ratio. The effect of this leakage was studied on MR images by comparing liver contrast enhancement after injection and after almost total removal of the contrast agent from the blood by exchange transfusion. Capillary leakage of CMD-Gd-DTPA was detected in lymph. Compared to Gd-DOTA, it was slower (ILRn = 0.36 10(-5) l min-1 for CMD-Gd-DTPA and ILRn = 2.6 10(-5) l min-1 for Gd-DOTA), less abundant (max Cl/Cp was 80% for CMD-Gd-DTPA and 100% for Gd-DOTA). Liver enhancement remained stable, which indicated that the leakage did not modify the enhancement induced by the intravascular fraction of the contrast agent. These results obtained in a highly permeable capillary model indicate that this agent can be used as a selective blood pool enhancer.
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Affiliation(s)
- N Siauve
- Laboratoire de Recherche en Imagerie, Faculté de Médecine Necker, Paris, France
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Durand-Zaleski L, Frija G, Raphaël JC. [Evaluation in radiology]. J Radiol 1995; 76:997-8. [PMID: 8594188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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49
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de Kerviler E, Bely N, Laccourreye O, Clément O, Halimi P, Frija G. The aryepiglottic fold as a rare location of adenoid cystic carcinoma. AJNR Am J Neuroradiol 1995; 16:1375-7. [PMID: 7677046 PMCID: PMC8337823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We report one case of a mass in the aryepiglottic fold seen on CT, which proved to be an adenoid cystic carcinoma. There was nothing specific about the imaging characteristics that would allow it to be confidentially differentiated from squamous cell carcinoma.
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Affiliation(s)
- E de Kerviler
- Department of Radiology, Boucicaut Hospital, Paris, France
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50
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Durand-Zaleski I, Vasile N, Lemaire F, Aubry S, Frija G. Management audit in a French department of radiology. Radiology Committee. Invest Radiol 1994; 29:797-801. [PMID: 7960633 DOI: 10.1097/00004424-199408000-00012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- I Durand-Zaleski
- Department of Public Health, Hôpital Henri Mondor, Créteil, France and the Department of Radiology
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