[Magnetic resonance angiography of the renal arteries]. / Angiographie par résonance magnétique des artères rénales.

Initially, the clinical use of magnetic resonance angiography (MRA) in the abdomen has been restricted because of motion and flow related artifacts. The advent of high performance gradient systems made possible the development of 3D gadolinium-enhanced MRA techniques and expanded the clinical applications of MRA into the abdominal area, particularly for the investigation of renal arteries. This technique is safe, because the administered contrast agent (gadolinium) is free of clinically detectable nephrotoxicity and has a low incidence of allergic reactions. Moreover, contrast MRA also eliminates the risks of ionizing radiation which allows repeating the examination without the accumulation of radiation exposure. The main disadvantages of the technique are its low availability and the fact that the use of contrast agents for this procedure is still not reimbursed by the social security. Many studies demonstrated that contrast MRA allows for the reliable assessment of renal artery morphology and pathologic states. Furthermore, within a single MR examination a comprehensive approach including renal artery morphology, hemodynamic significance of any stenosis and kidney perfusion is available. In this paper, we provide a review of the literature concerning the clinical performance of contrast MRA for the renal arteries and suggest its rationale for the investigation of patients suspected of renovascular disease in our specific environment.

Imaging of abdominal aortic aneurysms after endoluminal repair.

The recently published clinical trials of endoluminal repair of aortic aneurysms underline the need for a close imaging follow-up of patients undergoing these procedures. This article discusses the role of different imaging modalities in the evaluation of these patients.

Penetrating atherosclerotic ulcer of the descending thoracic aorta: treatment by endovascular stent-graft.

PURPOSE: To present four cases of penetrating ulcer of the descending thoracic aorta treated by transfemoral insertion of an endoluminal stent-graft. METHODS: Four patients with penetrating aortic ulcers were reviewed. Three cases were complicated by rupture, false aneurysm, or retrograde dissection. All patients were treated by endovascular stent-graft and were followed by helical computed tomography (CT). RESULTS: Endovascular stent-graft deployment was successful in all patients. However, in one case we observed a perigraft leak that spontaneously disappeared within the first month, and two interventions were needed for another patient. Following treatment, one episode of transient spinal ischemia was observed. The 30-day survival rate was 100%, but one patient died from pneumonia with cardiac failure 34 days after the procedure. In one patient, helical CT performed at 3 months showed a false aneurysm independent of the first ulcer. This patient refused any further treatment and suddenly died at home (unknown cause) after a 6-month follow-up period. CONCLUSION: Transluminal placement of endovascular stent-grafts for treatment of penetrating ulcers of the descending thoracic aorta appears to be a possible alternative to classical surgery. After treatment, follow-up by CT is essential to detect possible complications of the disease.

The wirsungorrhagies: causes and management in 14 patients.

BACKGROUND AND STUDY AIMS: Wirsungorrhagy is an extremely rare cause of upper gastrointestinal bleeding. The present study describes 14 cases observed over a seven-year period. MATERIAL AND METHODS: Among 10,000 endoscopic retrograde cholangiopancreatographies performed between 1989 and 1996 we have identified 14 wirsungorrhagies, which were reviewed retrospectively. They occurred in patients with chronic and acute pancreatitis, and primary and metastatic pancreatic cancer. RESULTS: Clinical signs of bleeding were present in six patients; three other patients had occult blood loss, and in five patients wirsungorrhagy was caused by endoscopic manipulation (n=3) or extracorporeal shock-wave lithotripsy (n=2) without clinical or hemodynamic effects. In six patients, wirsungorrhagy was managed by endoscopic methods. Five patients in unstable clinical conditions had an arteriography which allowed identification and treatment of the source of bleeding in three cases. Two patients with bleeding from a communicating cyst in chronic pancreatitis underwent surgery. CONCLUSIONS: Wirsungorrhagy can be responsible for massive bleeding in certain patients, especially those with chronic pancreatitis and pseudoaneurysm. In these cases, arteriography is most useful for identification and treatment of the bleeding. When it occurs during endoscopic manipulations, it can usually be managed endoscopically and/or stops spontaneously with appropriate main pancreatic duct drainage. When it occurs in patients with pancreatic tumors, optimal treatment is surgical resection; this is, unfortunately, usually not feasible.

Helical CT of aorta after endoluminal stent-graft therapy: value of biphasic acquisition.

OBJECTIVE: We report our prospective study evaluating biphasic helical CT of the aorta after endoluminal stent-graft placement. SUBJECTS AND METHODS: Biphasic helical CT scans in 95 patients with abdominal and thoracic aortic aneurysms who had undergone endoluminal stent-graft placement were reviewed. After a test bolus injection of 15 ml of contrast media at a rate of 3.5 ml/sec for the measurement of the optimal start delay, the aorta was scanned using the following parameters: collimation of 5 mm, table speed of 7 mm per rotation, tube rotation time of 0.75 sec, 120 kV, and 295 mA. A delayed helical CT scan was obtained 15 sec after the initial acquisition using the same parameters. RESULTS: Biphasic helical CT scans showed perigraft leakage in 45 (47%) of 95 patients. Leakage was shown only on arterial phase CT in eight patients and only on the delayed scans in three patients. In two patients, leakage shown on the delayed acquisition was retrospectively seen on the first scan. Leakage and outflow vessels were most visible on the arterial phase acquisition in 17 patients and on the second acquisition in six patients. Overall, biphasic acquisition was superior to arterial phase acquisition alone in 15 (16%) of 95 patients. CONCLUSION: The diagnostic value of biphasic helical CT is superior to arterial phase acquisition alone for the evaluation of the aorta after endoluminal stent-graft therapy.

[Percutaneous treatment of an osteoid osteoma of the scapula using a laser under scanner control]. / Traitement percutané d'un ostéome ostéoïde de l'omoplate par laser sous contrôle scanner.

The authors report a new therapeutic modality used in a patient with an osteoid osteoma of the scapula. The young patient complained of pain increasing over the last 4 years and not responding to medical therapy. The nidus was successfully destroyed by percutaneous laser photocoagulation under CT guidance. Clinical improvement was manifest after 72 hours and the patient remained asymptomatic at 8 months follow-up.

Transcatheter embolization of pseudoaneurysms complicating pancreatitis.

PURPOSE: To evaluate the therapeutic role of angiography in patients with pseudoaneurysms complicating pancreatitis. METHODS: Thirteen symptomatic pseudoaneurysms were treated in nine patients with pancreatitis. Eight patients had chronic pancreatitis and pseudocyst and one had acute pancreatitis. Clinical presentation included gastrointestinal bleeding in seven patients and epigastric pain without bleeding in two. All patients underwent transcatheter embolization. RESULTS: Transcatheter embolization resulted in symptomatic resolution in all patients. Rebleeding occurred in two patients, 18 and 28 days after embolization respectively, and was successfully treated by repeated embolization. One patient with severe pancreatitis died from sepsis 28 days after embolization. Follow-up was then available for eight patients with no relapse of bleeding after a mean follow-up of 32 months (range 9-48 months). CONCLUSION: Transcatheter embolization is safe and effective in the management of pseudoaneurysms complicating pancreatitis.

Endovascular aortic stent-grafts: transcatheter embolization of persistent perigraft leaks.

PURPOSE: To assess efficacy of transcatheter embolization of peri prosthetic leaks from aortic stent-grafts MATERIALS AND METHODS: Eight patients with a long-standing (3-13 months) perigraft leak after stent-graft implantation underwent transcatheter embolization. Leakage was demonstrated at helical computed tomography (CT). Angiography was performed for evaluation of outflow vessels and transcatheter embolization. All patients underwent helical CT follow-up after the procedure and every 3 months. RESULTS: Embolization was successful in seven patients and resulted in aneurysmal sac thrombosis. A second procedure was necessary in one patient to complete occlusion of the aneurysm. No further aneurysmal growth was detected during 4-9 months follow-up. Right leg paresis was observed in one patient immediately after the procedure, but symptoms disappeared completely after 8 days. Another patient had a minor sensory deficit in the region of the right crural nerve. CONCLUSION: Transcatheter embolization of perigraft leaks appears to be an effective technique to achieve aneurysmal thrombosis.

[Imaging of acquired pathologies of the thoracic aorta]. / Imagerie des pathologies acquises de l'aorte thoracique.

For many years, imaging of thoracic aorta has been dominated by angiography. Development of new imaging modalities has modified the diagnostic approach to thoracic aortic pathology. The knowledge of the advantages and limitations of each technique enables a better choice for patient evaluation, in particular under emergency conditions. This study is based on a review of the literature and reports the authors' experience.

[Emergency treatment of hemobilia using embolization]. / Traitement en urgence d'une hémobilie par embolisation.

Embolotherapy has gained widespread acceptance as the modality of choice for the management of hemobilia because of its safety profile. Our case reports a successful transcatheter embolization of the right hepatic artery aneurysm causing hemobilia in a patient in hemodynamic instability.

[Placing of a Nitiol Memotherm prosthesis: personal experience]. / Mise en place de la prothèse en Nitinol Memotherm: notre experience.

The authors report their experience in the placement of a new Nitinol stent. Thirty eight stents were placed in 28 iliac arteries, 3 superficial femoral arteries, 1 popliteal artery, 2 subclavian arteries, and 2 veins of hemodialysis fistulae. The primary success rate was 100%, but several angioplasty balloons have been ruptured due to the specific configuration of the stent. The mean follow-up period was 6 months. Memotherm placement is an easy procedure, but the specific structure of the device makes the manipulation of the angioplasty balloons delicate, especially in tortuous vessels.

[Abdominal complications of ventriculoperitoneal shunts]. / Complications abdominales de shunts ventriculo-péritoneaux.

Three cases of abdominal complications of ventriculo-peritoneal shunts are reported. Abdominal pseudocysts were identified in 2 patients (surinfection was proven in one of them). Malposition of the shunt was demonstrated for the third patient. Ultrasound was the most helpful imaging technique for the detection of these abdominal complications. Abdominal computed tomography confirmed the sonographic findings before the patients were reoperated.

Hyperechoic thickened ependyma: sonographic demonstration and significance in neonates.

In the neonate, hyperechoic thickening of the ependyma is believed to be related to ventriculitis. Yet, in our experience, this sign is much more often observed in association with subacute intraventricular hemorrhage (IVH), without infection. Sixty premature neonates were prospectively studied. The observations of transfontanellar sonograms (intracranial hemorrhage, ependymal echogenicity, and ventriculomegaly) were correlated with the results of MRI, lumbar punctures and clinical work-up. Intracranial hemorrhage was detected in 28 patients, and hyperechoic thickening of the ependyma was observed in 21 of them, all of whom had IVH. In 9 of these 21 patients IVH was diagnosed retrospectively thanks to the visualization of the hyperechoic ependyma. In all but one, this sign persisted for at least 2 months after disappearance of other signs of IVH. MRI demonstrated the presence of hemosiderin and ferritin in ependymal or subependymal location only in patients with hyperechoic ependyma. One of our patients had in utero diagnosis of IVH owing to the visualization of the same hyperechoic aspect of the ependyma. Nine of the neonates with hyperechoic ependyma developed ventriculomegaly, and three underwent surgery. Hyperechoic thickening of the ependyma in prematures often results from a subacute IVH. It is related to hemoglobin catabolites which can be detected by MRI. It does not require immediate potentially harmful diagnostic punctures. The presence of this hyperechoic rim allows a retrospective diagnosis of IVH and indicates a clinical and sonographic follow-up in newborns at risk for secondary hydrocephalus.