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Dive into the research topics where A. Ravel is active.

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Featured researches published by A. Ravel.


CardioVascular and Interventional Radiology | 2003

Management of Splenic Artery Aneurysms and False Aneurysms with Endovascular Treatment in 12 Patients

R. Guillon; J.M. Garcier; Armand Abergel; R. Mofid; V. Garcia; T. Chahid; A. Ravel; Denis Pezet; L. Boyer

AbstractPurpose: To assess the endovascular treatment of splenic artery aneurysms and false aneurysms. Methods: Twelve patients (mean age 59 years, range 47–75 years) with splenic artery aneurysm (n = 10) or false aneurysm (n = 2) were treated. The lesion was asymptomatic in 11 patients; hemobilia was observed in one patient. The lesion was juxta-ostial in one case, located on the intermediate segment of the splenic artery in four, near the splenic hilus in six, and affected the whole length of the artery in one patient. In 10 cases, the maximum lesion diameter was greater than 2 cm; in one case 30% growth of an aneurysm 18 mm in diameter had occurred in 6 months; in the last case, two distal aneurysms were associated (17 and 18 mm in diameter). In one case, stent-grafting was attempted; one detachable balloon occlusion was performed; the 10 other patients were treated with coils. Results: Endovascular treatment was possible in 11 patients (92%) (one failure: stenting attempt). In four cases among 11, the initial treatment was not successful (residual perfusion of aneurysm); surgical treatment was carried out in one case, and a second embolization in two. Thus in nine cases (75%) endovascular treatment was successful: complete and persistent exclusion of the aneurysm but with spleen perfusion persisting at the end of follow-up on CT scans (mean 13 months). An early and transient elevation of pancreatic enzymes was observed in four cases. Conclusion: Ultrasound and CT have made the diagnosis of splenic artery aneurysm or false aneurysm more frequent. Endovascular treatment, the morbidity of which is low, is effective and spares the spleen.


CardioVascular and Interventional Radiology | 2003

Percutaneous Transluminal Angioplasty of Dysplastic Stenoses of the Renal Artery: Results on 70 Adults

Bruno de Fraissinette; Jean Marc Garcier; Valérie Dieu; Reza Mofid; A. Ravel; Jean Yves Boire; Louis Boyer

Purpose: Retrospective analysis of the dilatation (PTRA) of renal arterial dysplastic stenosis (RADS). Methods: Seventy patients suffering from hypertension (87 RADS) were treated at our institution for medial (83%) or non-classified fibrodysplasias (17%). Four patients suffered from renal insufficiency. Two endoprostheses were implanted. We evaluated blood pressure with the USCSRH criteria and renal insufficiency with the Martin criteria. Results: Ninety-five percent technical success and 87.9% clinical success for blood pressure were obtained, with worse results for patients older than 57 years or with a history of hypertension greater than 9 years. Results were better when the RADS was responsible for an ipsilateral renal atrophy or for poorly controlled hypertension. No renal insufficiency worsened during the follow-up. Conclusion: PTRA is a first-line treatment for renovascular hypertension caused by RADS. The results were encouraging despite a high average age of the subjects and frequent associated extrarenal vascular lesions.


CardioVascular and Interventional Radiology | 2004

Endovascular treatment of chronic mesenteric ischemia: results in 14 patients.

T. Chahid; Agaicha T. Alfidja; Marie Biard; A. Ravel; Jean Marc Garcier; L. Boyer

We evaluated immediate and long-term results of percutaneous transluminal angioplasty (PTA) and stent placement to treat stenotic and occluded arteries in patients with chronic mesenteric ischemia. Fourteen patients were treated by 3 exclusive celiac artery (CA) PTAs (2 stentings), 3 cases with both Superior Mesenteric Artery (SMA) and CA angioplasties, and 8 exclusive SMA angioplasties (3 stentings). Eleven patients had atheromatous stenoses with one case of an early onset atheroma in an HIV patient with antiphospholipid syndrome. The other etiologies of mesenteric arterial lesions were Takayashu arteritis (2 cases) and a postradiation stenoses (1 case). Technical success was achieved in all cases. Two major complications were observed: one hematoma and one false aneurysm occurring at the brachial puncture site (14.3%). An immediate clinical success was obtained in all patients. During a follow-up of 1–83 months (mean: 29 months), 11 patients were symptom free; 3 patients had recurrent pain; in one patient with inflammatory syndrome, pain relief was obtained with medical treatment; in 2 patients abdominal pain was due to restenosis 36 and 6 months after PTA, respectively. Restenosis was treated by PTA (postirradiation stenosis), and by surgical bypass (atheromatous stenosis). Percutaneous endovascular techniques are safe and accurate. They are an alternative to surgery in patients with chronic mesenteric ischemia due to short and proximal occlusive lesions of SMA and CA.


Surgical and Radiologic Anatomy | 2001

Origin and initial course of the renal arteries a radiological study

J.M. Garcier; B. De Fraissinette; M. Filaire; P. Gayard; T. Therre; A. Ravel; Louis Boyer

The aim of this study was to determine the topography of the origin, implantation angle and initial course of the renal arteries in the transverse and frontal planes, from a prospective analysis of angiograms and helical CT-scans of 40 patients. In the frontal plane, the implantation angles of the right and left renal arteries were 73.8 ± 17° axsnd 65.6 ± 16° respectively 17.9% of the right renal arteries were straight compared with only 5% of the left ones. The first sinuosity was observed to be at a distance greater than the aortic diameter for 43.6% of right renal arteries and at a distance less than the aortic diameter for 62.5% for the left renal a. In the transverse plane, the right renal a. had an implantation angle of 65.6 ± 15.7° compared with 95.7 ± 16.85% for the left renal a. The artery was rectilinear in 2.6% of the cases on the right side, and in 2.5% of the cases on the left. The first sinuosity occurred before the lateral margin of the spine was reached in 60.5% of right renal arteries and after the margin of psoas major muscle for 55% of left renal arteries. A knowledge of the anatomy of the origin and initial course of the renal arteries is important when considering vessel dilatation and the implantation of stents in the renal arteries. No correlation was observed between the origin, sinuosity or angulation of the renal arteries which could aid interventional procedures.


Acta Radiologica | 2012

Endovascular treatment of eight renal artery aneurysms

Amr Abdel-Kerim; Lucie Cassagnes; A. Alfidja; Cristian Gageanu; Gregory Favrolt; Eric Dumousset; A. Ravel; Louis Boyer; Pascal Chabrot

Background Renal artery aneurysms (RAA) are a relatively rare vascular entity. Treatment could be either surgical or via an endovascular route. The main aim of therapy is to prevent lethal rupture. Purpose To evaluate the angiographic and clinical results after endovascular treatment (EVT) of eight renal artery aneurysms. Material and Methods From January 2000 to June 2011, 18 patients presented with 18 renal artery aneurysms. One was classified as Rundback type I, 15 were type II, and two aneurysms were type III. Endovascular treatment was considered unsafe in 10 cases (all were Rundback type II), and were referred to surgery. The remaining eight aneurysms were treated endovascularly during altogether nine sessions. Among these, four patients were asymptomatic, three were hypertensive, and one presented with ipsilateral flank pains. Aneurysmal sac diameter varied between 12 and 50 mm. EVT included selective coil embolization in five cases, covered stents in two cases, and parent artery occlusion in one. Results Follow-up with CT angiography was obtained in all endovascularly treated aneurysms (range 6–54 months, mean 15 months). Complete durable occlusion was achieved in all aneurysms except one, which showed re-expansion after 20 months and was retreated with covered stent implantation. Clinically silent, branch occlusion occurred after four procedures with subsequent limited (less than 25%) ischemic parenchymal loss. All patients were discharged with preserved renal function. Clinical improvement was noted in all symptomatic patients. Conclusion Endovascular treatment of renal artery aneurysms is an adequate treatment and can be proposed, if feasible, as first step.


CardioVascular and Interventional Radiology | 1994

Percutaneous Recanalization of Recent Renal Artery Occlusions: Report of 10 Cases

L. Boyer; A. Ravel; Annie Boissier; Marc Alexandre; Pascal Cluzel; Jean Claude Baguet; J. F. Viallet

PurposePercutaneous recanalization of renal artery occlusion was attempted in 10 patients.MethodsAll patients were hypertensive; before the procedure, the serum creatinine level was 80 μmol/L in one patient, ranged from 130–250 μmol/L in four patients, and was greater than 350 μmol/L in five, three of whom had anuria. Nine occlusions were thrombotic, one due to bilateral renal artery embolism. In four patients, percutaneous transluminal angioplasty of a contralateral renal artery stenosis was additionally performed; in two, renal artery occlusion was bilateral. In three patients, complementary local fibrinolysis was necessary.ResultsThree technical failures and one rethrombosis occurred after 24 h; in three of these cases the date of previous occlusion was unknown, whereas a relatively precise date was known for the seven other patients. One false aneurysm of the femoral artery was found 1 month after the procedure. One patient, after six technical successes, died 5 weeks after the procedure; follow-up for the other five was 6–36 months. Blood pressure was unchanged in four patients and improved in two. A significant and durable improvement of creatinine serum level (at least a 20% decrease) was observed in all six patients, usually after 1 month, thus enabling discontinuance of dialysis in three patients.ConclusionPercutaneous recanalization should be proposed in cases of renal artery occlusion, especially to avoid terminal vascular azotemia and dialysis.


Acta Radiologica | 2010

Revascularization of traumatic renal artery dissection by endoluminal stenting: Three cases:

Pascal Chabrot; Lucie Cassagnes; A. Alfidja; Jean Claude Mballa; Samer Nasser; Laurent Guy; A. Diop; A. Ravel; Louis Boyer

Traumatic injury of renal arteries is rare and can induce renal dysfunction and hypertension. Management options include observation, nephrectomy, surgical repair, and, more recently, percutaneous angioplasty. We report three cases of renal artery thrombosis occurring in young multitrauma patients (mean age 28.7 years) treated with stenting. Immediate satisfactory results were obtained in all cases. Postprocedure anticoagulant and antiplatelet treatment were given according to associated contraindicating lesions. During follow-up, in-stent restenosis occurred in one patient and was treated successfully with a second stenting procedure. No renal dysfunction or hypertension was observed after 28.6 months follow-up. Percutaneous angioplasty is a valuable alternative to surgical treatment in selected patients.


CardioVascular and Interventional Radiology | 2000

Spiral CT quantification of aorto-renal calcification and its use in the detection of atheromatous renal artery stenosis: A study in 42 patients

Pierre Gayard; J.M. Garcier; Jean-Yves Boire; A. Ravel; Nessim Perez; Privat C; Pascal Lucien; Jean-François Viallet; Louis Boyer

Purpose: To investigate whether a correlation exists between aortic and renal arterial calcifications detected with spiral CT and significant angiographic renal artery stenosis (RAS).Methods: Forty-two patients (mean age 67 years, range 37–84 years), of whom 24 were hypertensive, prospectively underwent abdominal helical CT and aortic and renal arteriography. The 3-mm thickness CT scans (pitch =1) were reconstructed each millimeter. A manual outline of the renal artery including its ostial portion was produced. Calcific hyperdensities were defined as areas of density more than 130 HU. CT data were compared with the presence or absence of RAS on angiography (24 cases); hypertension and age were taken into account (Mann-Whitney U-test).Results: CT detection and quantification appeared to be reliable and reproductible. We did not find any correlation between aortic and renal arterial calcifications and RAS, even for the patients above 65 years, with or without hypertension. There was no correlation either between calcifications and hypertension in patients without RAS.Conclusion: In this population, aortic and renal arterial calcifications have no predictive value for RAS.


International Urology and Nephrology | 2007

Palliative transarterial embolization of renal tumors in 20 patients

Laurent Guy; A. Alfidja; Pascal Chabrot; A. Ravel; Jean-Paul Boiteux; Louis Boyer

ObjectivesThe aim of this study is to evaluate immediate technical and clinical results of palliative transarterial renal embolization in patients with symptomatic renal tumors.MethodsParenchymal embolization of 20 renal tumors was performed in 20 symptomatic patients with hematuria and/or lumbar pain and/or para-neoplastic syndrome. Seven patients were inoperable because of poor general condition, and 15 patients had metastatic lesions.ResultsImmediate technical success was observed, with post-infarction pain in all patients requiring analgesia in 12 cases (which was successful in 90%); 8 patients had transitory fever. With a median follow up of 8.1 (range 4–27) months, recurrent hematuria was noted in two patients for which partial embolization was initially chosen; pain did not recur in any patients.ConclusionsPalliative embolization of advanced symptomatic renal tumors is easy to␣accomplish with low morbidity. It helps to alleviate invalidating symptoms in a multidisciplinary management of advanced renal tumors.


Acta Radiologica | 2012

Management of isolated non-traumatic renal artery dissection: report of four cases

Amr Abdel-Kerim; Lucie Cassagnes; A. Alfidja; Cristian Gageanu; Gregory Favrolt; Eric Dumousset; A. Ravel; Louis Boyer; Pascal Chabrot

Background Isolated non-traumatic renal artery dissection (RAD) is a rare disorder with uncertain natural history. The management may be surgical reconstruction, endovascular repair, or conservative medical treatment, yet no official consensus had been established. Purpose To report the management of four cases of isolated non-traumatic RAD, emphasizing the beneficial role of conservative medical treatment. Material and Methods From the year 2000 till 2011, four male patients with mean age of 42.5 years (range 34–48 years) presented with isolated non-traumatic RAD and were initially treated with medical therapy. Transcatheter in situ thrombolysis was performed in a case with thrombotic occlusion. Results Isolated non-traumatic RAD in four patients involving at least seven branches progressed to thrombotic occlusion in two branches, luminal narrowing in five, dual lumens in two, and aneurysmal dilatation in three. Medical treatment was efficacious in three patients, who showed persistent preserved renal function, controlled blood pressure, and favorable arterial remodeling. After failure of medical therapy, the fourth patient was referred to surgery. Thrombolysis was successful to dissolute an occluding thrombotic dissection. Conclusion Conservative therapy is safe and effective when the renal artery is patent and blood pressure is controlled: we propose it as the first line of treatment, reserving interventional management for refractory cases.

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Louis Boyer

Centre national de la recherche scientifique

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Pascal Chabrot

Centre national de la recherche scientifique

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A. Alfidja

Centre national de la recherche scientifique

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Laurent Guy

University of Auvergne

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D. Pezet

Environmental Research Institute of Michigan

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E. Buc

Environmental Research Institute of Michigan

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Armand Abergel

Centre national de la recherche scientifique

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