[Radiological investigations of arterial vascular disease: techniques and indications].
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Angiography, Digital Subtraction↗
Biomedical subjects
F Terrier
Publications and source records attributed to F Terrier.
MR cholangiopancreatography: technique, potential indications, and diagnostic features of benign, postoperative, and malignant conditions.
The objective of this article is to review technical aspects, discuss potential clinical indications for MR cholangiopancreatography (MRCP) and demonstrate the spectrum of diagnostic findings in benign, postoperative, and malignant conditions. We describe our current imaging protocol in comparison with other available techniques. Using a non-breath-hold, heavily T2-weighted fast-spin-echo (FSE) sequence with or without respiratory gating we obtained coronal and axial source images and maximum intensity projections (MIPs) in 102 patients with suspected abnormalities of the biliary or pancreatic ducts. Based on this series we demonstrate the diagnostic appearance of a variety of benign, postoperative, and malignant conditions of the biliary and pancreatic ducts and discuss potential clinical indications for MRCP. The non-breath-hold FSE technique enables a consistent image quality even in patients who cannot cooperate well. Respiratory gating increased the rate of diagnostic examinations from 79 to 95 %. Acquisition of coronal and axial source images enables detection of bile duct stones as small as 2 mm, although calculi that are impacted and not surrounded by hyperintense bile may sometimes be difficult to detect. The MIP reconstructions help to determine the level of obstruction in malignant jaundice, delineate anatomical variants and malformations, and to diagnose inflammatory conditions, e. g., sclerosing cholangitis, the Mirizzi syndrome and inflammatory changes in the main pancreatic duct. The MRCP technique also correctly demonstrates the morphology of bilio-enteric or bilio-biliary anastomoses. Because MRCP provides sufficient diagnostic information in a wide range of benign and malignant biliary and pancreatic disorders, it could obviate diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in many clinical settings. The ERCP technique may be increasingly reserved for patients in whom nonsurgical interventional procedures are anticipated.
Biliary Tract↗
Dynamic phosphorus-31 spectroscopy after fructose load in experimental biliary liver cirrhosis.
RATIONALE AND OBJECTIVES: The authors investigated the usefulness of dynamic phosphorus-31 magnetic resonance (MR) spectroscopy in the assessment of hepatic function by studying the effect of a fructose load on a rat model of liver cirrhosis. METHODS: In vivo P-31 MR liver spectra of eight rats with bile duct ligature and 10 control rats were obtained every 4.6 minutes before and after intraperitoneal fructose load (10 mmol per kilogram of body weight). RESULTS: In the basal spectra of the experimental group, the phosphomonoester peak was higher than in the control group (P = .026). After the fructose load, the phosphomonoester peak increase and the inorganic phosphate peak decrease were significantly less marked in the experimental group (P = .003). There was a linear correlation between the serum level of bilirubin and the phosphomonoester increase (r = .61, P < .001). CONCLUSION: Dynamic P-31 MR spectroscopy may be useful in the assessment of hepatic function in chronic liver disease.
Analysis of Variance↗
Computed tomography in acute left colonic diverticulitis.
BACKGROUND: The use of computed tomography (CT) in acute left colonic diverticulitis remains controversial. The purpose of this study was to define the value of CT both during the acute phase of inflammation and, later, to indicate secondary complications after successful medical treatment. METHODS: Some 423 patients with radiologically or histologically proven diverticulitis were studied prospectively from 1986 to 1995. Diverticulitis was considered moderate when CT showed localized thickening of the colonic wall (5 mm or more) and inflammation of pericolic fat; it was considered severe when abscess and/or extraluminal air and/or extraluminal contrast were observed. RESULTS: The sensitivity of CT was 97 per cent. Of 42 patients who failed conservative treatment, 32 had severe diverticulitis on CT, compared with 74 (24 per cent) of 303 who had successful conservative treatment (P < 0.0001). After a median follow-up of 46 months, 60 (20 per cent) of 300 patients had secondary complications despite initially successful conservative treatment: 28 (47 per cent) of these had initial severe diverticulitis on CT compared with 44 (19 per cent) of 236 patients who had no complications (P < 0.0001). CONCLUSION: Abscess formation and extracolonic contrast or gas are findings that may be used to predict failure of medical treatment during the first admission and a high risk of secondary complications after initially successful medical management of acute diverticulitis.
Acute Disease↗
Necrotizing fasciitis of the head and neck: role of CT in diagnosis and management.
PURPOSE: To determine the characteristic diagnostic features of necrotizing fasciitis and to evaluate the role of computed tomography (CT) in its management. MATERIALS AND METHODS: Fourteen patients with surgically proved necrotizing fasciitis of the extracranial head and neck were examined with contrast material-enhanced CT. Clinical, radiologic, surgical, pathologic, and anatomic findings at admission and after initial treatment were analyzed retrospectively. RESULTS: Constant CT features of necrotizing fasciitis were diffuse thickening and infiltration of the cutis and subcutis (cellulitis); diffuse enhancement and/or thickening of the superficial and deep cervical fasciae (fasciitis); enhancement and thickening of the platysma, sternocleidomastoid muscle, or strap muscles (myositis); and fluid collections in multiple neck compartments. Inconstant CT features included gas collections, mediastinitis, and pleural or pericardial effusions. All patients underwent extensive surgical debridement. Follow-up CT scans in 11 patients revealed clinically unsuspected progression of the inflammatory process in previously unaffected areas, a finding that warranted additional surgery in nine patients. Twelve patients survived, and two patients died of septic shock and aspiration pneumonia despite intensive surgical and medical treatment. CONCLUSION: Early recognition of necrotizing fasciitis with CT enables appropriate surgical treatment. CT may also be a useful guide in further patient treatment after initial surgical debridement.
Adolescent↗
Neoplastic invasion of the laryngeal cartilage: reassessment of criteria for diagnosis at CT.
PURPOSE: To evaluate eight different diagnostic criteria to help detect neoplastic invasion of laryngeal cartilage at computed tomography (CT). MATERIALS AND METHODS: In a prospective series, 111 patients with carcinoma of the larynx or hypopharynx underwent thin-section, contrast material-enhanced CT before total or partial laryngectomy. The following CT criteria were evaluated: extralaryngeal tumor, sclerosis, tumor adjacent to nonossified cartilage, serpiginous contour, erosion or lysis, obliteration of marrow space, cartilaginous blowout, and bowing. Histologic findings were correlated with findings on CT scans obtained at each level. RESULTS: Histologically, 122 of 412 cartilages were invaded. Depending on the diagnostic criteria and each specific cartilage, there was great variation in sensitivity (7%-83%) and specificity (40%-100%). Sclerosis was the most sensitive criteria in all cartilages but often corresponded to reactive inflammation in the thyroid cartilage. Extralaryngeal tumor and erosion or lysis yielded the highest specificity. Tumor adjacent to nonossified cartilage, serpiginous contour, and obliteration of marrow space were specific although not sensitive signs of invasion in the arytenoid and cricoid cartilage and were nonspecific in the thyroid cartilage. Blowout and bowing were not useful. Selection of the appropriate combination of criteria enabled an overall sensitivity of 91% (associated specificity, 68%) or an overall specificity of 79% (associated sensitivity, 82%). CONCLUSION: Detection of neoplastic cartilage invasion with CT greatly depended on the appropriate use of individual and combined CT criteria.
Adult↗
Choledocholithiasis and bile duct stenosis: diagnostic accuracy of MR cholangiopancreatography.
PURPOSE: To evaluate the accuracy of magnetic resonance (MR) cholangiopancreatography for detecting bile duct calculi and stenosis. MATERIALS AND METHODS: At MR cholangiopancreatography, 108 patients suspected of having bile duct calculi or stenosis were examined with two-dimensional fast spin-echo MR sequences and respiratory gating. On the basis of findings at surgery and/or intraoperative, endoscopic retrograde, and/or percutaneous cholangiography, final diagnoses were normal bile ducts (n = 38), choledocholithiasis (n = 23), Mirizzi syndrome (n = 3), benign or malignant bile duct stenosis (n = 40), choledochal cyst (n = 1), and bile duct dilatation without calculi or stenosis (n = 3). MR cholangiopancreatographic images were analyzed retrospectively by three reviewers who were unaware of final diagnoses. RESULTS: Choledocholithiasis was diagnosed with a sensitivity of 88%-92% and a specificity of 91%-98%. False-negative readings occurred because small or impacted calculi at the distal common bile duct or ampulla were difficult to detect or distinguish from stenosis. Bile duct stenosis was diagnosed with a sensitivity of 93%-100% and a specificity of 98%. Presence or absence of bile duct abnormality was assessed with a sensitivity of 97%-99% and a specificity of 95%-97%. Interobserver agreement was very good (kappa = 0.86-0.96). CONCLUSION: With MR cholangiopancreatography, bile duct calculi and stenoses can be diagnosed with high accuracy and good interobserver agreement.
Adult↗
In vivo human gastrocnemius architecture with changing joint angle at rest and during graded isometric contraction.
1. Human gastrocnemius medialis architecture was analysed in vivo, by ultrasonography, as a function of joint angle at rest and during voluntary isometric contractions up to the maximum force (MCV). maximum force (MVC). 2. At rest, as ankle joint angle increased from 90 to 150 deg, pennation increased from 15.8 to 27.7 deg, fibre length decreased from 57.0 to 34.0 mm and the physiological cross-sectional area (PCSA) increased from 42.1 to 63.5 cm2. 3. From rest to MVC, at a fixed ankle joint angle of 110 deg, pennation angle increased from 15.5 to 33.6 deg and fibre length decreased from 50.8 to 32.9 mm, with no significant change in the distance between the aponeuroses. As a result of these changes the PCSA increased by 34.8%. 4. Measurements of pennation angle, fibre length and distance between the aponeuroses of the gastrocnemius medialis were also performed by ultrasound on a cadaver leg and found to be in good agreement with direct anatomical measurements. 5. It is concluded that human gastrocnemius medialis architecture is significantly affected both by changes of joint angle at rest and by isometric contraction intensity. The remarkable shortening observed during isometric contraction suggests that, at rest, the gastrocnemius muscle and tendon are considerably slack. The extrapolation of muscle architectural data obtained from cadavers to in vivo conditions should be made only for matching muscle lengths.
Adult↗
Effects of antibiotic treatment in the subset of common-cold patients who have bacteria in nasopharyngeal secretions.
BACKGROUND: Upper-respiratory-tract infection is one of the main causes of overuse of antibiotics. We have found previously that bacteria such as Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae can be isolated from the nasopharyngeal secretions of a substantial proportion of adults with upper-respiratory-tract infections. We have assessed the efficacy of co-amoxiclav in patients with common colds but no clinical signs of sinusitis or other indications for antibiotics. METHODS: Between January, 1992 and March, 1994, 314 patients who presented to our outpatient clinic with common colds were enrolled in the double-blind, placebo-controlled study. They were randomly assigned 5 days' treatment with co-amoxiclav (375 mg three times daily) or identical placebo. Clinical examinations were done at enrolment and on day 5-7 to assess outcome (cured, persistent symptoms, worse symptoms). Seven patients were excluded after randomisation, seven did not have nasopharyngeal aspiration, and 12 did not return for followup assessment. FINDINGS: Of 300 patients with nasopharyngeal aspirates, 72 had negative bacterial cultures, 167 had cultures positive only for bacteria unrelated to respiratory infections, and 61 had cultures positive for H influenzae, M catarrhalis, or S pneumoniae. At 5-day follow-up of these culture-positive patients, the distribution of outcome was significantly better among co-amoxiclav-treated (n=30) than placebo-treated (n=28) patients (cured 27 vs 4%; persistent symptoms 70 vs 60%; worse symptoms 3 vs 36%; p=0.001). Patients on co-amoxiclav also scored their symptoms significantly lower than patients on placebo (p=0.008). Among culture-negative patients (n=230), the outcome distribution did not differ between the treatment groups (p=0.392). INTERPRETATION: The majority of patients with upper-respiratory-tract infection do not benefit from antibiotics and side-effects are frequent. However, for the subgroup whose nasopharyngeal secretions contain H influenzae, M catarrhalis, or S pneumoniae, antibiotics are clinically beneficial.
Adult↗
Segmental anatomy of the liver: a review and a proposal for an international working nomenclature.
The segmental anatomy of the human liver has become a field of increasing interest to radiologists during the past few years. The number of different terminologies which have been used since the topic has been systemically investigated is, however, a source of serious confusion. The present paper describes the reasons why the authors plead for an international working nomenclature which distinguishes a right hemiliver consisting of a right posterior and a right anterior segment, formed by subsegments 6 and 7, and 5 and 8, respectively, and a left hemiliver consisting of a left medial and a left lateral segment, the former corresponding to segment 4, and the latter to subsegments 2 and 3. This basic concept, however, must be carefully tailored to the highly variable individual anatomy of each patient. Furthermore, some aspects of hepatic segmentation are not yet understood and require additional anatomical investigation.
Humans↗
Three- to five-dimensional biomedical multisensor imaging for the assessment of neurological (dys) function.
This report describes techniques and protocols implemented at the Geneva Canton University Hospitals (HUG) for the combination of various biomedical imaging modalities and sensors including electromagnetic tomography, to study, assess, and localize neurological (dys) function. The interest for this combination stems from the broad variety of information brought out by (functional) magnetic resonance imaging, magnetic resonance spectroscopy, computed tomography, single-photon emission tomography, positron emission tomography, and electromagnetic tomography. Combining these data allows morphology, metabolism, and function to be studied simultaneously, the complementary nature of the information from these modalities becoming evident when studying pathologies reflected by metabolic or electrophysiologic dysfunctions. Compared with other current multimodality approaches, the one at the HUG is totally compatible with both clinical and research protocols, and efficiently addresses the multidimensional registration and visualization issues. It also smoothly integrates electrophysiology and related data as fully featured modalities.
Computer Graphics↗
Relationship between intrahepatic vessels and computer-generated hepatic scissurae: an in vitro assay.
Liver segmentation is a matter of increasing importance for radiologists, in particular with respect to accurate preoperative localisation of focal hepatic lesions. Procedures for delineating the segmental anatomy from CT or MR images are therefore much in demand. In this context, a convenient technique for generating the intersegmental scissurae by computer has recently been proposed [9]. The procedure, however, seemed questionable from an anatomical point of view. We therefore checked its relevance using anatomical vascular casts of post mortem livers and comparing the computer-generated scissurae with the actual course of the intrahepatic vessels. The results presented in this paper confirm that a rigid application of flat scissural planes is not able to render the real intrahepatic compartmentation. Only techniques considering the effective individual vascular anatomy can provide a correct determination of the hepatic segments.
Aged↗
Duplicated hepatic artery: radiologic and surgical implications.
Preoperative angiography of the coeliac trunk and superior mesenteric artery is routinely performed before liver resections and transplantations. For this purpose, it is usual to inject each branch of the coeliac trunk separately. Selective angiographic studies, however, may lead to overlooking surgically essential anatomic variations of the hepatic blood supply, as demonstrated by the present report. A case of a duplicated hepatic artery is presented, its radiologic and surgical implications discussed, and the relevant literature reviewed. This uncommon and particularly evocative feature illustrates the clinical importance of a sound knowledge of anatomical variants.
Adult↗
Clinical tolerance and diagnostic efficacy of iobitridol 300 in lower limb angiography.
PURPOSE: The diagnostic efficacy and the clinical tolerance of iobitridol 300 was evaluated in 68 patients receiving intraarterial injection in 2 monocentric comparative randomized double-blind trials with iopromide 300 (30 patients) and iopamidol 300 (40 patients) as reference. RESULTS; There is no significant difference in quality of opacification or in diagnostic efficacy between the products in each trial. No major adverse reactions occurred after the injection of iobitridol 300. Excluding a heat sensation, 5 of the patients who received iobitridol had minor reactions consisting of nausea with vomiting and pain during the injection. Five patients in the reference group also experienced adverse events. CONCLUSION: Iobitridol is well tolerated after intraarterial administration and it has the same diagnostic quality as iopromide and iopamidol.
Angiography↗
[Prevalence of medullary sponge kidney in patients with and without nephrolithiasis].
Reports on the prevalence of medullary sponge kidneys have given conflicting results. The present work is aimed at defining the prevalence of this abnormality in renal stone formers compared with a non-stone-forming control population by strict radiological criteria. Three separate studies have been carried out: the retrospective analysis of 191 intravenous urographies, which had been performed in 1988; the respective prospective analysis of 104 consecutive intravenous urographies and of 149 consecutive urographies, which had been performed at the end of intravenous digitalized subtraction renal angiographies. The 444 patients were classified according to presence or absence of nephrolithiasis. After exclusion of 70 patients (16%) of which the X-ray didn't fulfill the quality criteria, urographies were classified as 'medullary sponge kidneys', 'papillary blush' or 'negative' according to the radiological aspect of the papillae. Diagnosis of medullary sponge kidneys was based on presence of at least three linear or round papillary opacities seen in at least on papilla even of one kidney on late films (at least ten minutes after injection of contrast medium), taken without ureteral obstruction or abdominal compression. Overall results reveal that prevalence of a medullary sponge kidney in renal stone formers (8.5%) is significantly (p < 0.01) higher than in the control population (1.5%) and higher than what has been generally reported. Results of the retrospective and of both prospective analysis did not significantly differ. The best diagnostic tool to unmask medullary sponge kidneys remains urography.
Angiography, Digital Subtraction↗
[Acute hemorrhagic diarrhea caused by Klebsiella oxytoca: associated with virginiamycin?].
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Acute Disease↗
Magnetic resonance imaging with superparamagnetic iron oxide particles to evaluate hepatic macrophage-monocytic phagocytosis after arterial devascularization in minipigs.
RATIONALE AND OBJECTIVES: We examined the effects of arterial ischemia on the phagocytic activity of the hepatic macrophage-monocytic phagocytic system (MMPS). METHODS: Six minipigs were studied before and 24 hr after complete arterial devascularization of the liver. Magnetic resonance (MR) imaging was performed at 1.5 T using superparamagnetic iron oxide (SPIO) particles (18 mumol Fe/kg body weight) as an MMPS-specific contrast agent. Hepatobiliary scintigraphy, measurements of serum liver enzymes, and histology also were obtained. RESULTS: On MR imaging, the postcontrast-to-precontrast ratios of the arterially devascularized livers were significantly higher than the corresponding baseline values (p < .01). The greatest difference (52%) between the baseline and the postoperative values was observed on gradient-echo (GE) images. Scintigraphy, laboratory analyses, and histology results indicate that the MR imaging findings were probably predominantly attributable to a reduction in phagocytic activity of the hepatic MMPS. CONCLUSION: SPIO particles have already proved useful for improving detection of liver neoplasms on MR imaging, but they also may provide a novel way of evaluating the function of the hepatic MMPS in liver diseases.
Animals↗
Enhancement of computed tomography liver contrast using iomeprol-containing liposomes and detection of small liver tumors in rats.
RATIONALE AND OBJECTIVES: We evaluated iomeprol-containing liposomes (Lipiom), a new contrast medium for computed tomography (CT) liver scanning, in an animal model of chemically induced hepatocellular carcinomas and other liver tumors in rats. METHODS: Liver tumors were induced by administration of carcinogens to rats, either 0.55% (w/w) 1'-hydroxysafrole in the diet or induction by 3'-methyl-4-diethylaminoazobenzene followed by promotion with carbon tetrachloride. CT scanning was performed 1-3 hr after intravenous injection of iomeprol-containing liposomes. RESULTS: After injection of iomeprol-containing liposomes at a dose of 70 mg of liposome-entrapped iodine per kilogram of body weight, the normal liver parenchyma showed a contrast enhancement, in Hounsfield units, of more than 60% over the control value before bolus. Liver tumors with no or few Kupffer cells were not enhanced and appeared as dark areas within the normal parenchyma. Tumors and pretumoral lesions devoid of Kupffer cells, as small as 3 mm in diameter, could be distinguished using this non-invasive method. CONCLUSION: CT liver scanning after injection of iomeprol-containing liposomes appears to be promising method for detecting liver tumors and focal liver lesions.
Animals↗