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M F Bellin

Publications and source records attributed to M F Bellin.

At least 19 recordsLinked to original sources
PubMed2003

Currently used non-specific extracellular MR contrast media.

Magnetic resonance contrast agents have demonstrated their clinical usefulness in a variety of organs for improved detection of various neoplastic, inflammatory and functional abnormalities. Gadolinium chelates are the most widely used. They are extracellular, non-specific contrast agents. Their use in many clinical indications is justified because, in conjunction with improved imaging techniques, these safe and image-enhancing contrast agents add morphologic and functional information compared with unenhanced MR images. This article describes the commercially available compounds, and summarizes their approval status on the international market regarding indications and doses. Their mechanisms of action, biodistributions, toxicities and tolerance profiles in normal and high-risk patient populations are described. Additionally, this article reviews the specific recommendations by the manufacturers for patients at risk. Finally, their main clinical applications are reviewed.

Chelating Agents↗
PubMed2002

Contrast medium extravasation injury: guidelines for prevention and management.

Extravasation of contrast material is a well-recognized complication of contrast-enhanced imaging studies. The management of this complication is contentious; therefore, the Contrast Media Safety Committee of The European Society of Urogenital Radiology decided to review the literature and issue guidelines. A comprehensive literature search was carried out. The resulting report was discussed at the 8th European Symposium on Urogenital Radiology in Genoa, Italy. Automated power injection may result in extravasation of large volumes and may or can lead to severe tissue damage. Infants, young children and unconscious and debilitated patients are particularly at risk of extravasation during contrast media injection. Fortunately, most extravasations result in minimal swelling or erythema, with no long-term sequelae; however, severe skin necrosis and ulceration may occur. Large volumes of high osmolar contrast media are known to induce significant tissue damage. Compartment syndrome may be seen associated with extravasation of large volumes. Conservative management is often adequate, but in serious cases the advice of a plastic surgeon is recommended. Based on the review simple guidelines for prophylaxis and management of contrast medium extravasation injuries are proposed.

Adult↗
PubMed2000

MR imaging features of acute bilateral renal cortical necrosis.

Bilateral renal cortical necrosis (BRCN) is an uncommon cause of acute renal failure. Kidney biopsy, arteriography, and contrast-enhanced computed tomography (CT) are usually used to diagnose BRCN. However, these methods can have potentially serious side effects. We report two cases in which magnetic resonance imaging (MRI) evidenced characteristic features of BRCN, which were confirmed by histological findings and arteriography and correlated with clinical evolution. In the first case report, the diagnosis of a massive and complete cortical necrosis variety was suggested on MRI that showed a thin rim of low signal intensity along border of kidneys. It was confirmed on kidney biopsy, and the renal function did not recover. The second case is an incomplete form with cortical patchy areas of low signal intensity. In these two patients, MRI helped to establish an early diagnosis of BRCN with characteristic representative findings, without the potential nephrotoxic effects of iodinated contrast that has to be used in CT and arteriography. Kidney biopsy, besides the risks of complications, provides only a parceled analysis of the renal tissue and therefore does not allow any conclusion as to the extension of cortical necrosis. MRI may be of great help for the diagnosis and follow-up of acute renal cortical necrosis.

Adult↗
PubMed2000

Iron oxide-enhanced MR lymphography: initial experience.

The detection of nodal metastases is of utmost importance in oncologic imaging. Ultrasmall superparamagnetic iron oxide particles (USPIO) are novel contrast agents specifically developed for MR lymphography. After intravenous administration, they are taken up by the macrophages of the lymph nodes, where they accumulate. They reduce the signal intensity (SI) of normally functioning nodes on postcontrast T2-and T2*-weighted images through the magnetic susceptibility effects on iron oxide. Metastatic nodes, in which macrophages are replaced by tumor cells, show no significant change in SI on postcontrast T2-and T2*-weighted images. Early clinical experience suggests that USPIO-enhanced MR lymphography improves the sensitivity and specificity for the detection of nodal metastases. It also suggests that micrometastases could be detected in normal-sized nodes. This article reviews the physiochemical properties of USPIO contrast agents, their enhancement patterns, and early clinical experience.

Contrast Media↗
PubMed2000

Transjugular versus percutaneous renal biopsy for the diagnosis of parenchymal disease: comparison of sampling effectiveness and complications.

PURPOSE: To compare the effectiveness and safety of transjugular renal biopsy with those of percutaneous renal biopsy for diagnosis of renal parenchymal disease. MATERIALS AND METHODS: Results and complications of 400 consecutive transjugular renal biopsies performed between 1993 and 1998 with a modified Colapinto transjugular hepatic biopsy system were compared retrospectively with those of 400 percutaneous renal biopsies performed during the same period. Transjugular renal biopsy was associated with 14 cardiac and 35 hepatic biopsies. Number of glomeruli per tissue core, adequacy of tissue core for histopathologic diagnosis, and rate and severity of complications were analyzed. RESULTS: Renal tissue was obtained with percutaneous renal biopsy in 382 (95.5%) of 400 patients and with transjugular renal biopsy in 383 (95.8%) of 400 patients. The mean numbers of intact glomeruli per tissue core with optical microscopy were 11.2 +/- 7.7 (SD) and 9.8 +/- 7.6 for percutaneous renal biopsy and transjugular renal biopsy, respectively. With immunofluorescent microscopy, the mean numbers were 6.4 +/- 5.3 and 4.6 +/- 4.6 for percutaneous renal biopsy and transjugular renal biopsy, respectively. Tissue cores were adequate for histopathologic diagnosis in 98.2% with both techniques. Major complications occurred with transjugular renal biopsy in four patients and with percutaneous renal biopsy in three patients. CONCLUSION: Use of transjugular renal biopsy provides diagnostic yield and safety similar to those of percutaneous renal biopsy and allows multiorgan biopsy during the same procedure. It can be recommended in patients with percutaneous renal biopsy contraindication or failure.

Adult↗
PubMed1999

Focal nodular hyperplasia of the liver on ferumoxides-enhanced MR imaging: features on conventional spin-echo, fast spin-echo and gradient-echo pulse sequences.

The aim of this study was to assess the efficacy of a superparamagnetic iron oxide, ferumoxides, in the detection and characterization of focal nodular hyperplasia (FNH) on MR conventional spin-echo (SE), fast spin-echo (FSE) and gradient-echo (GRE) images. Fourteen adults with 27 FNHs were evaluated at 1.5 T before and after injection of ferumoxides. T1-weighted and T2-weighted SE, T2-weighted FSE and T2(*)-weighted GRE sequences were used and analysed qualitatively and quantitatively. One hundred percent of FNHs showed a significant postcontrast decrease in signal intensity on T2- and T2*-weighted images. Heavily T2-weighted SE images showed the maximum decrease in FNH signal-to-noise ratio (S/N). Postcontrast GRE T2(*)-weighted images improved the detection of the central scar and the delineation of FNHs and demonstrated the best lesion-to-liver contrast-to-noise ratio (C/N). Postcontrast T1-weighted SE images showed the least lesion-to-liver C/N. Ferumoxides-enhanced MR imaging can help detect and characterize FNH. Conventional pre- and postcontrast T2-weighted SE images and postcontrast GRE T2*-weighted images should be used preferentially.

Adult↗
PubMed1999

[Uroradiology].

Explore the source record for details and available documents.

Adrenal Gland Diseases↗
PubMed1999

[Colonic tubular adenoma following ureterosigmoidostomy: CT features].

We report a case of benign colonic tubular adenoma arising in a 36-year-old female at the site of ureterosigmoidostomy performed 25 years before. The tumor was revealed by recurrent episodes of pyelonephritis; hydronephrosis was present. On colonic enema, the tumor appeared lobulated, 4 cm in diameter. CT scan showed a multiloculated mass, which enhanced after injection. Pathology revealed a tubular adenoma of the colon with cystic dilatation of glandular structures. The role of imaging studies in the follow-up of patients after ureterosigmoidostomy is discussed.

Adenoma↗
PubMed1998

Review article: Overview of medical treatments in unresectable hepatocellular carcinoma--an impossible meta-analysis?

BACKGROUND: Controversies surrounding medical treatment in patients with unresectable hepatocellular carcinoma continue to persist. AIM: To perform a meta-analysis of therapeutic modalities which had been evaluated in two or more randomized trials. METHODS: Fifty-two randomized trials were studied; only 30 were included. This overview identified seven therapeutic modalities which had been evaluated in two or more trials: adriamycin, 5-fluorouracil, interferon, percutaneous ethanol injection, transarterial chemotherapy, the combination of lipiodol with transarterial chemotherapy, and tamoxifen. RESULTS: Comparisons of survival between control groups showed substantial heterogeneity. There was no survival benefit at 1 year with adriamycin (mean difference 4%), 5-fluorouracil (mean difference -3%), percutaneous ethanol injection (mean difference 6%) or transarterial chemotherapy (mean difference -2%). For interferon, the survival benefit was significant with the Der Simonian & Laird method (mean difference 9%, 95% CI = 1-18%, P = 0.04) but not with the Peto et al. method (2.4 mean odds ratio, 95% CI = 0.9-6.8). The meta-analysis of tamoxifen showed a borderline survival benefit (mean difference 25%, 95% CI = 0-49%, P = 0.05). However, in sensitivity analyses, the survival benefit of tamoxifen was no longer significant. CONCLUSIONS: No treatment has clearly proven efficacy in survival. 5-Fluorouracil, adriamycin and transarterial chemotherapy were not associated with survival benefit at 1 year. The number of randomized controlled trials was insufficient to enable a conclusion to be reached for interferon and percutaneous ethanol injection. Controversy persists concerning tamoxifen efficacy. Interferon and tamoxifen require new randomized controlled trials on a larger population of patients.

Administration, Cutaneous↗
PubMed1998

Lymph node metastases: safety and effectiveness of MR imaging with ultrasmall superparamagnetic iron oxide particles--initial clinical experience.

PURPOSE: To evaluate the clinical and biologic safety of ultrasmall superparamagnetic iron oxide particles (AMI-227) as a contrast agent for magnetic resonance (MR) lymphography and to assess their efficacy for the differentiation of metastatic and benign nodes in patients with urologic and pelvic cancer. MATERIALS AND METHODS: Thirty adults suspected of having lymph node metastases underwent MR imaging before and 22-26 hours after intravenous infusion of AMI-227 (1.7 mg Fe/kg). Sixty histopathologically proved lymph nodes were analyzed on MR images, and 29 of these nodes were also analyzed quantitatively. RESULTS: AMI-227 was well tolerated with no major side effects. It allowed the detection of 10 additional nodes relative to those detected at MR imaging without AMI-227. None of the 27 metastatic nodes showed a decrease in signal intensity (SI) on AMI-227-enhanced images; nine of 27 metastatic nodes showed an increase in SI on T1-weighted images, probably resulting from altered capillary permeability in the tumor. A visually perceptible reduction in SI, indicating active AMI-227 uptake, was observed on postcontrast T2- and T2*-weighted images in 16 of 21 benign nodes. The SI ratio of benign nodes was lower than that of metastatic nodes on T2- and T2*-weighted images. The sensitivity of AMI-227-enhanced MR lymphography was 100%, and the specificity was 80%. CONCLUSION: AMI-227 is safe and may facilitate the differentiation of metastatic and benign nodes in patients with urologic and pelvic cancers.

Adult↗
PubMed1998

[Subacute intestinal obstruction due to bladder distension].

We report a case of subacute bowel obstruction due to a compression of the rectosigmoid junction by a chronically distended bladder, occurring in a 91-year-old male suffering from a long-standing diabetes mellitus and a prostatic adenoma. Radiographic, water-soluble contrast enema and pelvic CT features are reported.

Aged↗
PubMed1998

[Spontaneous intraperitoneal rupture of the ureter].

An unusual case of spontaneous intraperitoneal rupture of the ureter was observed in adult with acute renal pain. Diagnosis was best established with CT rather than intravenous urography. CT demonstrated ureteral leakage with the contrast medium extravasating into the peritoneal cavity. The patient was initially managed successfully by endourology. Secondary stenosis of the ureter required surgery for partial resection of the distal ureter.

Adult↗
PubMed1997

[Imaging of small renal tumors].

The increased incidence of detection of small renal tumours, less than or equal to 3 cm in diameter, is related to the generalization and improvement of radiological techniques. Many asymptomatic renal tumours are discovered by ultrasonography and computed tomography. Medical imaging is now able to identify simple cysts (morphological characters, absence of blood supply), angiomyolipomas (demonstration of the fatty contingent) and other solid renal tumours (tumour enhancement on computed tomography). Plain, followed by postcontrast CT looking for contrast enhancement of the lesions is the examination of choice in this context. MRI with Gadolinium injection looking for neoplastic enhancement can be useful in doubtful cases. Medical imaging is able to reliably demonstrate the vascular nature of solid lesions, but cannot distinguish between renal cancer, oncocytoma or another benign solid tumour. Medical imaging allows precise preoperative mapping when partial nephrectomy is envisaged.

Adenoma, Oxyphilic↗
PubMed1996

Demonstration of efficacy of combining corticosteroids and colchicine in two patients with idiopathic sclerosing mesenteritis.

Sclerosing mesenteritis is an uncommon condition of unknown etiology. It is likely to be the fibrous evolution of mesenteric panniculitis. It often has an indolent course but may be complicated by progressive bowel obstruction. The treatment of the symptomatic forms is not well established. The observations of two women (20 and 65 years old) with a relentless downhill course of biopsy-proved sclerosing mesenteritis are described. A treatment regimen with corticosteroid therapy (initially 1 mg/kg/day) and colchicine (1 mg/day) led, in both cases, to a rapid improvement. Abdominal computer tomography showed reduction in the tumor size. The combination of corticosteroids and colchicine is helpful in the management of symptomatic sclerosing mesenteritis. Follow-up with abdominal computed tomography is useful in evaluating the therapeutic impact.

Adult↗
PubMed1996

Osteoid osteoma: CT-guided percutaneous excision confirmed with immediate follow-up scintigraphy in 16 outpatients.

PURPOSE: To evaluate treatment of osteoid osteoma with computed tomography (CT)-guided percutaneous excision and immediate follow-up scintigraphy. MATERIALS AND METHODS: Sixteen consecutive adolescent and adult patients underwent CT-guided percutaneous excision of a nidus with 14-gauge biopsy cutting needles, with local anesthesia. After the presence of nidus was confirmed at immediate follow-up scintigraphy, curettage of the bored cavity was performed to remove any residual fragments of the nidus. Scintigraphic and histologic findings were correlated. RESULTS: The nidus was removed successfully in 14 of the 16 patients, with no complications (mean follow-up, 15 months; range, 3-25 months). In five of the 14 patients, immediate follow-up scintigraphy showed incomplete resection of the nidus and immediate second resection was successful. Surgical resection was necessary in two of the 16 patients. CONCLUSION: CT-guided percutaneous excision with immediate follow-up scintigraphy was safe and effective for localization and removal of osteoid osteoma in outpatients.

Adult↗