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J Pringot

Publications and source records attributed to J Pringot.

At least 37 records · Page 2Linked to original sources
PubMed1997

Detection and segmental location of malignant hepatic tumors: comparison of ferumoxides-enhanced gradient-echo and T2-weighted spin-echo MR imaging.

OBJECTIVE: The aim of our prospective study was to compare the values of ferumoxides-enhanced gradient-echo and T2-weighted spin-echo MR imaging for the detection and segmental location of malignant hepatic tumors. SUBJECTS AND METHODS: Eighteen patients underwent ferumoxides-enhanced T2 weighted spin-echo and steady-state gradient-echo imaging before surgery. Intraoperative sonography was used as the reference examination and showed 28 malignant tumors involving 39 of the 144 hepatic segments. The MR images were reviewed independently by two observers who recorded the number of tumors and their segmental location. The results of the segmental location were subjected to receiver-operating-characteristic analysis. Tumor-liver, vessel-liver, and tumor-vessel contrast-to-noise ratios were calculated. RESULTS: Detection on the gradient-echo images did not differ significantly from that on the T2-weighted spin-echo MR images (observers A and B detected 23 and 24 tumors, respectively, on the gradient-echo images; the two observers each detected 22 tumors on the T2-weighted spin-echo images). Segmental localization was significantly better on the gradient-echo images than on the T2-weighted spin-echo images (mean area under the receiver-operating-characteristic curve: 0.974 versus 0.895 for observer A and 0.962 versus 0.906 for observer B, p = .024). The highest contrast-to-noise ratios for vessel to liver and tumor to vessel were obtained on the gradient-echo images and the highest tumor-liver contrast-to-noise ratio was obtained on the T2-weighted spin-echo images. CONCLUSION: In our study, ferumoxides-enhanced gradient-echo imaging was as accurate as T2-weighted spin-echo imaging for revealing malignant hepatic tumors and was superior for showing their segmental location.

Contrast Media↗
PubMed1997

Early diagnosis of acute intestinal ischaemia: contribution of colour Doppler sonography.

The aim of this study was to evaluate the contribution of colour Doppler sonography in the diagnosis of acute intestinal ischaemia. In a two years experience, all patients admitted for acute abdominal pain in our emergency department were evaluated with colour Doppler sonography of the abdomen. The final diagnosis based on clinical evolution, endoscopic or surgical findings and further radiological investigations was compared to the sonographic results. Therapy and final outcome of the patients with acute intestinal ischaemia were also evaluated. In twenty-one patients a final diagnosis of acute intestinal ischaemia (mesenteric ischaemia (n = 13) and ischaemic colitis (n = 8)) was made. Intestinal ischaemia was correctly diagnosed by initial clinical and biological data and further confirmed by sonography in eight cases (mesenteric ischaemia (n = 2) and ischaemic colitis (n = 6)). Eleven other cases were detected by suggestive colour Doppler sonography features (mesenteric ischaemic (n = 10) and ischaemic colitis (n = 1)). Sixteen of the 21 patients had a final favourable outcome (mesenteric ischaemia (10/ 13) and ischaemic colitis (6/8)). We conclude that sonography has a place in the diagnosis of acute intestinal ischaemia and has to be integrated in the diagnostic algorithm of this acute condition. By this way, this diagnosis may be suspected earlier and may allow a prompt and adapted treatment with possible improvement in survival rate.

Abdominal Pain↗
PubMed1997

Post-traumatic intrahepatic pseudoaneurysm: diagnosis with helical CT angiography and management with embolization.

The authors report a case of liver trauma with hematoma complicated with a pseudoaneurysm. The latter was suspected on day 7, with a monophasic helical CT and was demonstrated with helical CT angiography. Arteriography confirmed the lesion and showed an associated arteriovenous fistula, unsuspected on helical CT. The pseudoaneurysm was managed with transcatheter embolization, completed with percutaneous embolization because of vascular spasm.

Accidents, Traffic↗
PubMed1996

Reperfused ischemia of the rat intestine: detection by MR imaging with polylysine-Gd-DTPA enhancement.

To detect reperfused ischemia of the rat intestine, T2-weighted spin-echo images were acquired, followed by T1-weighted images before and after administration of polylysine-Gd-DTPA or Gd-DTPA. Before administration of the contrast agent, the reperfused intestine was hyperintense on T2-weighted images, and to a lesser extent on T1-weighted images. After administration of polylysine-Gd-DTPA, the reperfused intestine enhanced more than the normal one, giving a significantly better contrast-to-noise (CNR) ratio than on unenhanced images. Gd-DTPA induced the same enhancement of the reperfused and the normal intestine and the CNR was lower than on unenhanced T2-weighted images. Reperfused intestinal ischemia could thus be better detected on polylysine-Gd-DTPA-enhanced MR images than on unenhanced images or on Gd-DTPA-enhanced images.

Animals↗
PubMed1996

MRI of the anal canal: correlation with histologic examination.

The purpose of this study was to correlate the MRI features of the anal canal with histologic findings. T1- and T2-weighted MR images of nine anal canals were obtained after fixation in 10% formalin. In three specimens, imaging was repeated after removal of histologic layers with a dissecting microscope. Corresponding histologic slices were stained with hematoxylin-eosin, Masson trichrome, and periodic acid-Schiff. Four layers were visualized on T2-weighted images. An inner layer of high signal intensity and a second layer of low signal intensity corresponded to the mucosa as well as mucous secretions and to the submucosa. The high signal intensity layer vanished at the distal part of the anal canal in accordance with the lack of mucus-secreting epithelium below the level of the dentate line. A third layer of intermediate signal intensity corresponded to the internal sphincter. A fourth layer of low signal intensity corresponded to the longitudinal muscle and external sphincter. T2-weighted MRI is capable of showing the internal architecture of the wall of the anal canal. In particular, the internal sphincter can be differentiated from the external sphincter and longitudinal muscle.

Anal Canal↗
PubMed1996

Laparoscopic splenectomy in adults and children: experience with 31 patients.

BACKGROUND: Open surgery is the standard approach for splenectomy in hematologic disorders, but a few cases of successful laparoscopic splenectomy have been reported. METHODS: Thirty-one patients (18 adults, group 1; and 13 children, group 2) underwent laparoscopic splenectomy. Indications for surgery included idiopathic thrombocytopenic purpura (25 patients), congenital spherocytosis (4 patients), and hemolytic anemia (2 patients). In 97% of the patients the diameter of the spleen was less than 15 cm. RESULTS: Laparoscopic splenectomy was successful in 94% of the patients; conversion to open surgery was mainly related to hemorrhage. Accessory spleen was found in 39% in group 1 and 8% in group 2. Two adults received intraoperative autotransfusion. Postoperative morbidity was minimal. The median postoperative stay was 3 days (range, 2 to 12 days) in group 1 and 2 days (range, 2 to 5 days) in group 2. CONCLUSIONS: Laparoscopic splenectomy is safe in both adults and children. Adequate selection of patients (small-size spleen, splenic destruction on preoperative scanning of platelets), appropriate preparation in patients with idiopathic thrombocytopenic purpura (immunoglobulin G), and meticulous surgical technique (with routine opening of the gastrocolic ligament to search for accessory spleen) are key factors in obtaining the same long-term results as with open surgery.

Adolescent↗
PubMed1996

Detection of hepatic metastases: ferumoxides-enhanced MR imaging versus unenhanced MR imaging and CT during arterial portography.

PURPOSE: To prospectively compare the diagnostic accuracy of computed tomography (CT) during arterial portography (CTAP) with that of unenhanced and ferumoxides-enhanced magnetic resonance (MR) imaging at 0.5 T in the detection of hepatic metastases. MATERIALS AND METHODS: Four pairs of radiologists independently assessed the metastatic involvement of 134 hepatic segments (31 with and 103 without metastasis) in 17 patients at unenhanced and ferumoxides-enhanced spin-echo and gradient-echo MR imaging (alone and in combination) and at CTAP. The diagnostic performance of the various imaging modalities was assessed by means of receiver operating characteristic analysis. RESULTS: The accuracy of CTAP, unenhanced MR imaging (combined unenhanced sequences), and ferumoxides-enhanced MR imaging (combined contrast material-enhanced sequences) was 0.925, 0.908, and 0.951, respectively. Ferumoxides-enhanced MR imaging was significantly more accurate (P < .05) than unenhanced MR imaging and CTAP. When 14 segments containing cysts were excluded, the difference between ferumoxides-enhanced MR imaging and CTAP was no longer statistically significant (P = .1). CONCLUSION: Ferumoxides-enhanced MR imaging is more accurate than unenhanced MR imaging and at least as accurate as CTAP for the detection of hepatic metastases.

Adult↗
PubMed1996

Ferristene as intestinal MR contrast agent. Distribution and safety of a fast ingestion procedure with oral metoclopramide.

PURPOSE: To compare the small bowel distribution and safety of a fast ingestion procedure of ferristene to those of the standard ingestion procedure. MATERIAL AND METHODS: Sixty-four patients received 0.5 g/l ferristene in 800 ml water. Thirty-four patients of the fast ingestion group ingested ferristene with 20 mg of oral metoclopramide during the course of 30 min before MR imaging and received an i.v. injection of an antiperistaltic agent during the MR study. Thirty patients of the standard group ingested ferristene during the course of 2 h, without additional drugs. Ferristene distribution was assessed by 2 reviewers and adverse events were recorded. RESULTS: More than 50% of the small bowel segments analyzed were filled with ferristene in 30 patients in the fast ingestion group and in 28 patients in the standard ingestion group. One patient in each group experienced nausea and/or vomiting. Some bloating or sensation of fullness was reported by 2 patients in the fast ingestion group and by 3 patients in the standard ingestion group. CONCLUSION: The distribution of ferristene in the small bowel and the safety of the procedure were thus similar in the 2 groups using either a fast ingestion procedure with oral metoclopramide or the more time-consuming standard ingestion procedure.

Administration, Oral↗
PubMed1996

Acute intestinal ischemia due to occlusion of the superior mesenteric artery: detection with Doppler sonography.

The aim of our study was to assess the feasibility of using Doppler sonography for the detection of acute intestinal ischemia due to occlusion of the superior mesenteric artery. Between September 1993 and March 1995, abdominal sonography with Doppler imaging of the mesenteric vessels was performed in 770 patients with emergency admissions for acute abdominal pain. In six cases, the diagnosis, based on surgery or arteriography and computed tomography, was acute intestinal ischemia due to complete or localized occlusion of the superior mesenteric artery. Five cases of occlusion of the superior mesenteric artery were correctly detected by Doppler sonography. These results suggest that Doppler sonography may be a feasible method for detecting acute intestinal ischemia due to proximal superior mesenteric artery occlusion.

Adult↗
PubMed1996

[Value of echography in the diagnosis of acute intestinal occlusion].

OBJECTIVE: The aim of our study was to assess the value of sonography in the diagnosis of acute intestinal occlusion. MATERIAL AND METHODS: Sonographic findings were reviewed in 50 cases of intestinal occlusion (39 small bowel and 11 colonic occlusions). The final diagnosis was based on surgical findings (n = 40) or clinical course and further imaging findings (n = 10). RESULTS: Occlusion was correctly detected with sonography in 48 cases (96%). The location was correctly established with sonography in 43 cases (86%). The precise cause was suggested with sonography in 21 cases (42%). COMMENTARY: These results confirm the value of sonography for the diagnosis of intestinal occlusion and the identification of its level and its cause.

Acute Disease↗
PubMed1996

[Follow-up of TIPS: evaluation of signs of dysfunction with Doppler ultrasonography].

PURPOSE: to assess the signs of TIPS dysfunction at Doppler sonography. MATERIALS AND METHODS: retrospective study of signs observed in 106 TIPS including 31 TIPS with dysfunction (portoauricular pressure gradient > 12 mmHg). RESULTS: the signs of TIPS dysfunction were a decrease in the mean velocity in the TIPS (for a velocity < 40 cm/sec, 90% sensitivity, 96%), a hepatopetal intrahepatic portal flow (on the right 90% sensitivity, 100% specificity, on the left 95% sensitivity, 92% specificity), a lack of cardiac modulation of the signal in the TIPS (93% sensitivity, 65% specificity), a hepatic vein flow reversal (30% sensitivity, 100% specificity), and, the only direct sign of stenosis, an increase of the mean velocity in the stenosis (42% sensitivity, 95% specificity for a velocity > or = 1 m/sec). CONCLUSION: the most sensitive Doppler signs of tips dysfunction are the indirect signs of stenosis.

Adult↗
PubMed1995

Comparison of gadolinium-DTPA and polylysine-gadolinium-DTPA--enhanced magnetic resonance imaging of hepatocarcinoma in the rat.

RATIONALE AND OBJECTIVES: To compare the magnetic resonance (MR) imaging characteristics of gadolinium-DTPA (Gd-DTPA), a low-molecular-weight contrast agent, and polylysine-Gd-DTPA, a macromolecular contrast agent, in two types of hepatocarcinomas (HCC) in the rat. METHODS: T1-weighted spin-echo images were obtained in 13 rats with chemically induced HCC and 26 rats with Novikoff HCC before and 3 minutes to 60 hours after administration of either Gd-DTPA or polylysine-Gd-DTPA. RESULTS: Three minutes after polylysine-Gd-DTPA administration, the tumor-to-liver contrast of the two types of HCC increased significantly (positive contrast for chemically induced HCC and negative contrast for Novikoff HCC). At 30 minutes and 60 hours, the tumor-to-liver contrast remained above baseline values in chemically induced HCC and returned progressively to baseline values in Novikoff HCC. No significant increase in tumor-to-liver contrast was observed after Gd-DTPA administration. CONCLUSIONS: These results suggest that polylysine-Gd-DTPA provides a higher and more prolonged increase in tumor-to-liver contrast than Gd-DTPA.

Angiography↗
PubMed1995

[Spiral CT of the bile ducts].

The multiplanar capability of spiral CT improves the evaluation of bile duct lesions. In particular, spiral CT after intravenous administration of a cholangiographic agent (spiral CT cholangiography) provides adequate 2D and 3D images of the bile ducts in patients with normal bilirubin levels. Spiral CT cholangiography may be particularly useful as a noninvasive imaging method to detect biliary anatomic variations and bile duct stones before or after laparoscopic cholecystectomy. This technique does not replace retrograde cholangiography which has therapeutic applications, but might help to select patients who need to undergo invasive procedures such as retrograde cholangiography.

Bile Duct Neoplasms↗
PubMed1995

Pulmonary sequestration. Visualization of an enlarged azygos system by CT.

The purpose of this study was to determine the prevalence of enlargement of the azygos system in the case of lung sequestration and its potential usefulness in the differential diagnosis of lower lobe opacities. Seven consecutive adult cases of pulmonary sequestrations were retrospectively enrolled; 4 sequestrations were proved surgically and all 7 angiographically. A group of 50 consecutive patients with a normal chest CT were used as controls. Another group consisted of 25 consecutive patients identified on the basis of an opacity in a posterobasal location on chest CT. For the 3 groups, the maximum diameter of the azygos and hemiazygos veins was measured, the level of measurement located between the upper poles of the kidneys and the confluence of inferior pulmonary veins into the left atrium. The diameter of the azygos veins (mean 10.4 +/- 5.1 mm) and of the hemiazygos veins (mean 7.1 +/- 3.0 mm) in the sequestration group was significantly larger than the diameter of the azygos and hemiazygos veins in the control group (mean 5.7 +/- 2.5 mm, and 3.4 +/- 2.4 mm, respectively), as well as in the study group (mean 5.9 +/- 2.6 mm and 3.3 +/- 2.6 mm, respectively). Our results suggest that enlargement of the azygos system in association with a posterobasal chest opacity, although nonspecific, may be a useful additional CT sign of sequestration.

Adolescent↗
PubMed1995

[Iron oxides as contrast agents for MRI of the liver].

Iron oxide particles are a potent class of MR contrast agents. Depending on their size and formulation, iron oxides are selectively taken up by the reticuloendothelial system or the hepatocytes. Experimental and clinical studies have shown that iron oxides can improve the detection and the characterization of liver tumors and can contribute to the detection of diffuse liver lesions. These tissue-specific MR contrast agents combine anatomic and functional information about liver lesions.

Contrast Media↗
PubMed1994

Radiologic findings of normal and compromised thoracic venous catheters.

We review the radiologic findings of normal positioning, malpositioning, and complications related to the more commonly used thoracic venous catheters. These include central venous catheters, long-term central venous access catheters, and pulmonary artery catheters. The radiologist plays an important role in the early recognition of the complications of these catheters. The daily practice of chest radiology is intimately related to the evaluation of the integrity and correct placement of thoracic venous catheters. The purpose of this pictorial essay is to review radiologic findings of normal positioning, malpositioning, and complications related to the more common devices used, including central venous catheters, long-term central venous access catheters, and pulmonary artery catheters. Many of the complications described are serious and may remain unrecognized for a long time; this may cause incorrect diagnosis and delayed treatment. The radiologist plays an important role in the early recognition of these complications. Malpositioning and complications often are more easily diagnosed with contrast-enhanced studies and computed tomography.

Catheterization, Central Venous↗
PubMed1994

Noninvasive imaging of the biliary tree before or after laparoscopic cholecystectomy: use of three-dimensional spiral CT cholangiography.

OBJECTIVE: The purpose of this study was to determine the feasibility of using three-dimensional spiral CT after IV administration of a cholangiographic agent for noninvasive detection of anatomic variations of the bile ducts and common bile duct stones before or after laparoscopic cholecystectomy. SUBJECTS AND METHODS: Three-dimensional spiral CT cholangiography was performed before laparoscopic cholecystectomy in 24 patients and after surgery in two patients who had recurrent symptoms. After slow infusion of 250 ml of iodipamide, spiral CT was performed. Three-dimensional images of the bile ducts and a secondary reformation through the long axis of the common bile duct were obtained. Visualization of the biliary tract was evaluated by two observers. Detection of anatomic variations and common bile duct stones was assessed in 19 patients for whom a gold standard (operative or retrograde cholangiogram) was available. RESULTS: In all 26 patients, the common bile duct and the confluence of the hepatic ducts were seen on three-dimensional spiral CT cholangiograms, and in 21 patients second- or higher-order branches were also seen. Seven patients had anatomic variations and two had common bile duct stones. These anomalies were proved by operative cholangiography in each case, except for a low junction of the cystic duct and a common bile duct stone, which were shown by retrograde cholangiography. Six of the seven anatomic variations were adequately detected with spiral CT cholangiography, as were the two cases of common bile duct stones. CONCLUSION: Three-dimensional spiral CT cholangiography is a feasible method for noninvasive detection of biliary anatomic variations and common bile duct stones before or after laparoscopic cholecystectomy.

Bile Ducts↗