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Xavier Leclerc

Publications and source records attributed to Xavier Leclerc.

At least 19 recordsLinked to original sources
PubMed2006

Prognostic value of hyperintense vessel signals on fluid-attenuated inversion recovery sequences in acute cerebral ischemia.

BACKGROUND: Fluid-attenuated inversion recovery (FLAIR) sequences may reveal hyperintense vessel signals (HVS) at the acute stage of cerebral ischemia. The aim of this study was to test the hypothesis that HVS are associated with a worse outcome. METHODS: We included 30 consecutive patients admitted within 12 h after onset of hemispheric cerebral ischemia. The outcome was assessed with the modified Rankin Scale at month 1. RESULTS: Proximal HVS were present in 9 patients and distal HVS in 16. All patients with proximal occlusions on time-of-flight sequences had distal HVS on FLAIR. Patients with poor outcome at month 1 (modified Rankin Scale 3-6) more frequently had had HVS on MRI (12/13 vs. 4/17; p< 0.001). CONCLUSION: Distal HVS found on FLAIR sequences within 12 h of acute cerebral ischemia are associated with a worse 1-month outcome.

Adult↗
PubMed2006

Insular infarcts and electrocardiographic changes at admission: results of the PRognostic of Insular CErebral infarctS Study (PRINCESS).

BACKGROUND AND PURPOSE: Previous studies showed that insular strokes are associated with electrocardiographic (ECG) changes. However, they did not take into account the 1(st) ECG recorded at admission, but continuous ECG recorded up to 72 hours after onset. Whether these changes are the consequence of the infarct, or are associated with a cardiac source of cerebral ischemia, remains unsettled. If ECG changes are the consequence of insular infarcts, they should not have developed by the time of admission. The aim of this study was to test the hypothesis that ECG changes in patients with insular infarcts are not present at admission. METHODS: We recruited consecutive patients admitted within 48 hours (median 3 hours) after the onset of symptoms of acute hemispheric cerebral ischemia. We compared ECG variables between patients with and without insular infarcts, and with left and right insular infarcts. RESULTS: The study population consisted of 208 patients (94 men; median age: 69 years). Seventy patients had a recent insular infarct (right in 33). ECG variables did not significantly differ between patients with and without insular infarcts, and with left and right insular infarcts. These results were not explained by a lack of statistical power (1-beta >/= 0.90). CONCLUSION: The lack of statistical link between insular infarcts and ECG changes at admission, suggests that ECG changes are not associated with the cause of insular infarcts, but are their consequence.

Adolescent↗
PubMed2006

Intracranial aneurysms treated with Guglielmi detachable coils: imaging follow-up with contrast-enhanced MR angiography.

BACKGROUND AND PURPOSE: To compare the utility of contrast-enhanced MR Angiography (CE-MRA) with digital subtraction angiography (DSA) after endovascular treatment of intracranial aneurysms with Guglielmi detachable coils. METHODS: From April 1999 to August 2002, 106 patients with 107 aneurysms treated by endovascular coiling using Guglielmi detachable coils underwent simultaneous DSA and CE-MRA at follow-up (mean: 12.9 range: 5 to 27 months). DSA was performed as the standard reference. MR angiographic images were analyzed independently by 2 senior radiologists (J.-Y.G., S.C.) and DSA by a third radiologist (X.L.). Findings were assigned to 1 of 3 categories: complete obliteration (class 1), residual neck (class 2) and residual aneurysm (class 3). RESULTS: DSA at follow-up demonstrated 65 (60.6%) complete obliterations (group 1), 21 (19.7%) residual necks (group 2) and 21 (19.7%) residual aneurysms (group 3). One patient (0.9%) experienced aneurysm rebleed during the follow-up period. Among 101 assessable imaging comparisons, interobserver agreement was determined to be very good for CE-MRA (kappa=0.96) with only 4 discrepancies between both examiners. Comparison between CE-MRA and DSA showed an excellent agreement between techniques (kappa=0.93). Of the 21 with residual necks described on DSA, 20 were seen on CE-MRA. CE-MRA detected all 19 residual aneurysms. CONCLUSIONS: CE-MRA after selective embolization of intracranial aneurysm is useful and comparable to DSA in the assessment of aneurysmal recanalization either as residual neck or aneurysmal sac.

Adolescent↗
PubMed2006

Retractable self-expandable stent for endovascular treatment of wide-necked intracranial aneurysms: preliminary experience.

OBJECTIVE: Intracranial stenting combined with endosaccular coiling is a therapeutic alternative for the endovascular treatment (EVT) of wide-necked intracranial aneurysms. The current limitation of available stents is the impossibility to reposition them once they are partially deployed. Recently, the first retractable self-expandable stent has been developed and we sought to evaluate the use of this stent for EVT of wide-necked intracranial aneurysms. METHODS: Between March 2004 and March 2005, 11 patients with an unruptured aneurysm have been selected for this study. In all cases, previous attempts with EVT with the remodeling technique failed or was technically judged difficult. In all patients, EVT combined stent placement (Leo, Balt, Montmorency, France) across the aneurysm neck and subsequent coiling of the sac. Aneurysms were located on the carotid siphon (n = 9), the internal carotid artery bifurcation (n = 1), and the vertebral artery (n = 1). Aneurysms diameter size varied from 3 to 45 mm. Clinical outcome was assessed with the Modified Glasgow Outcome Scale. RESULTS: EVT was successfully performed and led to an excellent outcome in all patients. The stent could be navigated within cerebral arteries without any exchange procedure. Thanks to its retractability, the stent could precisely be positioned in all cases. Angiographic results consisted of 9 complete occlusions and 2 incomplete occlusions in 2 giant aneurysms. No procedure-related complication occurred. CONCLUSION: The Leo stent appears very useful for EVT of wide-necked intracranial aneurysms. The advantage of this stent is the possibility to reposition it which allows a very precise positioning across the aneurysm neck.

Adult↗
PubMed2005

Fluid-attenuated inversion recovery (FLAIR) sequences for the assessment of acute stroke: inter observer and inter technique reproducibility.

BACKGROUND AND PURPOSE: Diffusion-weighted magnetic resonance (MR) imaging (DWI), and three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA), are highly sensitive for the early detection of stroke and arterial occlusion. However, only a few studies have evaluated the sensitivity of conventional MR sequences that are usually included in the imaging protocol. The aim of this study was to evaluate interobserver and intertechnique reproducibility of Fluid-Attenuated Inversion Recovery (FLAIR) sequences for the diagnosis of early brain ischemia and arterial occlusion. METHODS: Over a 30-month period, brain MR examinations were performed in 34 patients within 12 hours after stroke onset. Imaging protocol included FLAIR sequences, DWI and 3D TOF MRA. Ten observers including radiologists and neurologists, performed separately a visual interpretation of FLAIR images for the detection of brain ischemia and arterial occlusion seen as an arterial high signal. DWI and 3D TOF MRA were used as reference and interpreted independently by two senior radiologists. Interobserver agreement was assessed for image quality, detectability and conspicuity of lesions whereas intertechnique agreement was only judged for lesion detectability. RESULTS: On FLAIR sequences, interobserver agreement for the detection of brain ischemia and arterial occlusion was excellent (kappa = 0.81 and 0.87 respectively). The concordance between FLAIR and DWI sequences for the detection of brain ischemia and between FLAIR and 3D TOF MRA for the detection of arterial occlusion were judged as excellent for all observers (kappa = 0.91 and 0.89 respectively). CONCLUSION: Although DWI is the most sensitive technique with which to detect acute stroke, FLAIR imaging may also be useful to demonstrate both acute ischemia and arterial occlusion with an excellent interobserver reproducibility.

Adult↗
PubMed2005

Three-dimensional dynamic magnetic resonance angiography for the evaluation of radiosurgically treated cerebral arteriovenous malformations.

We assessed the value of three-dimensional (3D) dynamic magnetic resonance angiography (MRA) for the follow-up of patients with radiosurgically treated cerebral arteriovenous malformations (AVMs). Fifty-four patients with cerebral AVMs treated by radiosurgery (RS) were monitored using conventional catheter angiography (CCA) and 3D dynamic MRA with sensitivity encoding based on the parallel imaging. Cerebral AVM was qualitatively classified by two radiologists into one of five categories in terms of residual nidus size and persistence of early draining vein (I, >6 cm; II, 3-6 cm; III, <3 cm; IV, isolated early draining vein; V, complete obliteration). 3D MRA findings showed a good agreement with CCA in 40 cases (kappa=0.62). Of 23 nidus detected on CCA, 3D dynamic MRA showed 14 residual nidus. Of 28 occluded nidus on 3D dynamic MRA, 22 nidus were occluded on CCA. The sensitivity and specificity of 3D dynamic MRA for the detection of residual AVM were 81% and 100%. 3D dynamic MRA after RS may therefore be useful in association with MRI and can be repeated as long as opacification of the nidus or early venous drainage persists, one CCA remaining indispensable to affirm the complete occlusion at the end of follow-up.

Adult↗
PubMed2005

Matrix detachable coils for the endovascular treatment of intracranial aneurysms: analysis of early angiographic and clinical outcomes.

BACKGROUND AND PURPOSE: Endovascular coil embolization has become an accepted alternative for the treatment of intracranial aneurysms. The purpose of this study was to evaluate the clinical safety and the angiographic stability of aneurysm occlusion with a new class of biologically active platinum coils after a 6-month period. METHODS: Twenty-five patients with 25 intracranial aneurysms were treated by selective embolization with a new coated bioactive coil (Matrix; Boston Scientific Neurovascular). Matrix coils were used alone in 6 patients and in combination with Guglielmi detachable coils (GDCs; Boston Scientific Neurovascular) in 19. Angiographic results, procedure-related complications, and adverse neurological events during the follow-up period were recorded. Magnetic resonance angiography was performed at 6 months in all patients. RESULTS: Initial angiographies demonstrated complete occlusion in 17 patients, residual neck in 7, and a persisting aneurysm in 1. The clinical follow-up showed stable results in all patients. The grade of aneurysm occlusion at 6 months improved in 4 patients, remained stable in 15, and deteriorated in 6. Three patients needed retreatment because of a major aneurysm recanalization. Angiographic recurrences in cases of aneurysms treated with a combination of Matrix coils and GDCs occurred within the expected range for bare platinum coils. Two of 3 patients needing retreatment had been treated with Matrix coils alone. CONCLUSIONS: Stable results were obtained predominantly when Matrix coils were combined with bare platinum coils. A prospective, randomized study is necessary to assess the potential benefit of Matrix coils for patients treated by endovascular techniques.

Adult↗
PubMed2005

3D rotational angiography: use of propeller rotation for the evaluation of intracranial aneurysms.

We compared two methods of 3D digital subtraction angiography (DSA)--propeller and standard rotation--for the assessment of aneurysmal morphology and its relation to neighboring vessels. Aneurysms were correctly visualized and localized with both techniques. 3D DSA with propeller rotation technique seems to be effective and allows us to reduce the amount of contrast material related to a shortened acquisition time. Technical progress including propeller rotation allows a larger range of rotation and faster rotational speeds.

Adolescent↗
PubMed2005

Intracranial aneurysms treated with Guglielmi detachable coils: usefulness of 6-month imaging follow-up with contrast-enhanced MR angiography.

BACKGROUND AND PURPOSE: This study was undertaken to assess the utility of contrast-enhanced MR angiography at 6 months after endovascular treatment of intracranial aneurysms with Guglielmi detachable coils. METHODS: Contrast-enhanced MR angiography was performed in 47 patients at 6 and 12 months after endovascular treatment of intracranial aneurysms (48 aneurysms). Digital subtraction angiography (DSA) was used as reference and was performed at 12 months after the treatment in all patients. MR angiographs were analyzed independently by two senior radiologists. DSA and MR angiography findings were assigned into one of three categories: complete obliteration, residual neck, or residual aneurysm. RESULTS: All examinations were assessable. Interobserver agreement was judged as very good for contrast-enhanced MR angiography (kappa=0.96), with one discrepancy between examiners. Comparison between MR angiography at 6 months and DSA at 12 months showed an excellent agreement between techniques (kappa=0.93). Two cases of complete occlusion at DSA were misclassified as a residual neck at 6-month MR angiography. All aneurysm recanalizations at DSA already were detected on MR angiography at 6 months. The size of aneurysm recanalization did not increase between both MR angiographs performed at 6 and 12 months. CONCLUSION: Contrast-enhanced MR angiography after selective embolization of intracranial aneurysm seems to predict properly early aneurysm recanalizations.

Adult↗
PubMed2004

Diffusion/perfusion-weighted magnetic resonance imaging after carotid angioplasty and stenting.

BACKGROUND AND PURPOSE: Carotid angioplasty and stenting, a so far non-validated procedure, may be an alternative to surgery in patients with a high surgical risk. However, it carries also a risk of cerebral embolic events. The purpose of this study was to evaluate tissue signal abnormalities in the brain before and after carotid angioplasty and stenting by means of diffusion- (DWI) and perfusion (PWI) weighted magnetic resonance imaging (MRI). METHODS: We performed cerebral MRI before and after carotid angioplasty in 22 consecutive patients, with 23 treated high-grade carotid stenoses. The lesions were located at the origin of the internal carotid artery (ICA) in 20 patients, and at the origin of the common carotid artery (CCA) in 2. MRI was performed the day before, and repeated within 24 hours after the procedure, and examined by two neuroradiologists. RESULTS: All stent implantations were successful but 4 patients developed an acute neurological deficit within 24 hours after carotid angioplasty. On PWI, Time To Peak (TTP) values ipsilateral to the carotid stenosis were increased before the procedure in 15 patients, and had remained normal in 6 and were not assessable in 1. After the procedure, TTP values were normal in 12 patients, increased in 8 and not assessable in 2. On DWI, new ipsilateral lesions were detected in 2 patients: 1 with an acute neurological deficit and 1 symptom free. CONCLUSION: Perfusion deficits may be present in severe carotid stenosis and be improved within 24 hours by carotid angioplasty and stenting. Asymptomatic infarcts may occur.

Aged↗
PubMed2004

Giant vertebrobasilar aneurysms: endovascular treatment and long-term follow-up.

OBJECTIVE: To report long-term imaging follow-up and clinical outcome of 13 patients with a giant vertebrobasilar aneurysm treated by parent artery occlusion (PAO). METHODS: From 1994 to 2000, 13 consecutive patients with a giant vertebrobasilar aneurysm were treated by PAO. Symptoms were related to mass effect in nine patients and to a subarachnoid hemorrhage in four. Endovascular treatment consisted of aneurysm trapping in nine patients and occlusion of one or both vertebral arteries in four. We assessed the clinical outcome and imaging findings in all patients during a 28-month period. RESULTS: Endovascular treatment resulted in clinical improvements in eight patients, worsening of symptoms in four, and death in one. One woman with a ruptured vertebral aneurysm died from a rebleeding after PAO without trapping. One man developed a brainstem infarction after lower basilar artery occlusion and incurred hemiparesis. In three patients, symptoms of mass effect increased after the procedure. Long-term follow-up revealed good or excellent clinical outcome in all patients and a sharp decrease in size of the thrombosed aneurysm in nine patients. One basilar aneurysm recanalized despite selective coiling and subsequent bilateral vertebral artery occlusion; one vertebral aneurysm and one basilar aneurysm did not decrease in size despite complete occlusion. CONCLUSION: Giant vertebrobasilar aneurysms are rare and challenging lesions for both neurosurgeons and neurointerventionalists. Their treatment by endovascular PAO remains safe and effective. Early clinical worsening may be observed, but long-term follow-up shows good or excellent results in most patients. This treatment can be carried out with minimal morbidity and mortality using clinical and angiographic monitoring.

Adolescent↗
PubMed2004

Endovascular treatment of ruptured intracranial aneurysms in elderly people.

BACKGROUND AND PURPOSE: Endovascular detachable coil is being increasingly used for the treatment of cerebral aneurysms but little information is available about its feasibility and effectiveness in people. We assessed clinical outcomes in elderly patients with ruptured intracranial aneurysms treated with selective embolization. METHODS: Between 1996 and 2002, 68 patients aged 65-80 years (mean age, 71 years) were treated by selective embolization with coils. Among them, 34 had a Hunt and Hess (HH) grade of I or II; 15, an HH grade of III; and 19, an HH grade of IV or V. All patients except four were treated within 72 hours after initial bleeding; those four patients had an HH grade of IV or V and were treated at 3-6 weeks after their clinical recovery. Clinical outcomes were assessed by using the Modified Glasgow Outcome Scale. Mean duration of follow-up was 20 months (range, 6-36 months). RESULTS: Endovascular treatment resulted in 47 complete occlusions (69%), 15 neck remnants (22%), and six incomplete occlusions (9%). Procedural complications occurred in eight patients (12%). Outcomes were good or excellent in 40 patients (59%), including the four treated 3-6 weeks after initial bleeding. A fair or poor outcome was observed in 14 patients (20.5%), including two with an HH grade of I or II. Of 14 patients (20.5%) who died, 13 (93%) had an HH grade of IV or V. No rebleeding occurred during follow-up. CONCLUSION: Endosaccular coiling may be proposed in elderly people with ruptured intracranial aneurysms. However, in patients with HH grade IV or V lesions, morbidity and mortality rates remain high, and embolization should be considered only after their clinical recovery.

Aged↗
PubMed2004

Selective endovascular treatment of intracranial aneurysms with sapphire coils.

BACKGROUND AND PURPOSE: Endovascular treatment with detachable coils is an accepted alternative to surgical clip placement for intracranial aneurysms. The purpose of this study was to evaluate the safety and reliability of the Sapphire coil, a new platinum coil for the treatment of intracranial aneurysms. METHODS: Between August and September 2003, 20 consecutive patients (13 women, seven men; mean age, 49 years; range, 33-77 years) with 20 intracranial aneurysms were referred to our department for endovascular treatment. Fifteen patients presented with subarachnoid hemorrhage, whereas five had asymptomatic, unruptured aneurysms. All patients were treated by selective endosaccular coil placement with the new coils. The remodeling technique was used in five wide-neck aneurysms. Clinical outcomes were assessed with the modified Glasgow Outcome Scale. RESULTS: Aneurysmal occlusion with the new coils alone was successful in 16 patients and resulted in 12 complete occlusions and four neck remnants. Because of the limited Sapphire product line, additional Guglielmi detachable coils (GDCs) were required in four patients, two of whom received one 3D GDC of 3 mm diameter and two of whom received Ultra-Soft GDCs. Technical complication (stretching of a coil) occurred in one patient. Clinical outcomes were excellent in 14 patients and good in two. CONCLUSION: Although the study was limited by its small patient population, the results show that selective endovascular treatment of intracranial aneurysms with Sapphire coils was not associated with an unexpected incidence of adverse events. Excellent anatomic and clinical results that were obtained in most patients suggest that Sapphire coils may have value in the treatment of intracranial aneurysms.

Adult↗
PubMed2004

HyperForm remodeling-balloon for endovascular treatment of wide-neck intracranial aneurysms.

A new, very compliant remodeling balloon microcatheter has been developed for the treatment of difficult wide-neck intracranial aneurysms (eg, arterial bifurcation or small artery aneurysms). We report selective embolization by the use of the remodeling technique with the HyperForm balloon in 16 consecutive patients with a wide-neck intracranial aneurysm located on an arterial bifurcation or a small artery or both.

Adult↗
PubMed2003

Cerebral magnetic resonance imaging within 6 hours of stroke onset: inter- and intra-observer reproducibility.

BACKGROUND: Magnetic resonance imaging (MRI) provides valuable pathophysiological information during the very first hours of cerebral ischemia. However, the reliability of prime-time MRI in the setting of emergency care remains unknown. AIM: To evaluate the reproducibility between and within observers of the assessment of MRI scans in stroke patients. METHOD: We performed a MRI scan within 6 h of stroke onset, with time-of-flight (TOF), T2* gradient echo, FLAIR, diffusion- (DWI) and perfusion- (PWI) weighted images, in 17 consecutive patients. Four observers, blinded to the clinical history, separately performed a visual assessment of all scans, and repeated the assessment 2-8 days later. Two neuroradiologists made volumetric measures of diffusion and perfusion abnormalities using a semi-automatic technique 2 weeks after the 2nd visual assessment. We evaluated: (i) in the whole set of MRI scans, the quality of scans and their ability to identify primary hemorrhages on T2* gradient echo sequences; (ii) in patients with acute cerebral ischemia only, the inter- and intra-observer agreement for the presence of arterial occlusion and cerebral abnormalities on TOF sequences, and (iii) on DWI and PWI sequences, the relationship between visual and automatic assessments for the presence of a mismatch (defined as the difference between the perfusion and diffusion abnormalities) of >20%. Statistics used the kappa (kappa) method. RESULTS: The median delay between clinical onset and MRI was 285 min. Two patients had primary cerebral hemorrhages, 1 a post-ictal deficit, and 14 cerebral ischemia. The quality of the scans was judged as appropriate for all scans in all sequences except for FLAIR. All observers identified the 2 patients with hemorrhages. The inter- and intra-observer reliability was substantial to excellent (kappa values ranging from 0.63 to 1.00) for all sequences. The agreement between visual and automatic assessments for the presence of a mismatch of >20% was excellent in all observers. CONCLUSION: The visual assessment of T2* gradient echo, TOF, diffusion and perfusion sequences at the acute stage of stroke is reproducible between and within observers. The visual assessment is as good as the volumetric assessment to detect a mismatch of >20%.

Adult↗