Biomedical subjects

Jean-Pierre Pruvo

Publications and source records attributed to Jean-Pierre Pruvo.

27 records · Page 2Linked to original sources

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

MRI in children with mental retardation.

BACKGROUND: In mental retardation (MR) an aetiological diagnosis is not always obtained despite a detailed history, physical examination and metabolic or genetic investigations. In some of these patients, MRI is recommended and may identify subtle abnormal brain findings. OBJECTIVE: We reviewed the cerebral MRI of children with non-specific mental retardation in an attempt to establish a neuroanatomical picture of this disorder. MATERIALS AND METHODS: Thirty children with non-specific MR were selected to undergo cerebral MRI. The examination included supratentorial axial slices, mid-sagittal images and posterior fossa coronal images. Brain malformations, midline and cerebellar abnormalities were studied. RESULTS: In 27 of 30 patients, the neuroimaging evaluation revealed a relatively high incidence of cerebral and posterior fossa abnormalities. The most frequent were: dysplasia of the corpus callosum (46%; hypoplasia, short corpus callosum and vertical splenium), partially opened septum pellucidum and/or cavum vergae (33%), ventriculomegaly (33%), cerebral cortical dysplasia (23%), subarachnoid space enlargement (16.6%), vermian hypoplasia (33%), cerebellar and/or vermian disorganised folia (20%), and subarachnoid spaces enlargement in the posterior fossa (20%). Other anomalies were: enlarged Virchow-Robin spaces (10%), white matter anomalies (10%) and cerebellar or vermian atrophy. CONCLUSIONS: MRI has shown a high incidence of subtle cerebral abnormalities and unexpected minor forms of cerebellar cortical dysplasia. Even if most of these abnormalities are considered as subtle markers of brain dysgenesis, their role in the pathogenesis of mental retardation needs further investigation.

Adolescent↗

PubMed2003

Poststroke dementia: influence of hippocampal atrophy.

BACKGROUND: The prevalence of dementia is increased after stroke. Medial temporal lobe atrophy (MTLA) is associated with Alzheimer disease, and with prestroke dementia in patients who have had a stroke. OBJECTIVE: To determine the influence of MTLA on the long-term risk of dementia after stroke, after excluding the patients who had prestroke dementia. METHODS: The study was conducted in 144 consecutive patients who had a stroke, who were aged 40 years or older (66 women and 78 men; median age, 72 years), and who had an Informant Questionnaire on Cognitive Decline in the Elderly score lower than 104. On admission to the hospital all patients underwent a noncontrast computed tomographic scan including temporal lobe-positioned slices. A cut-off of 11.5 mm was used to differentiate patients with MTLA from those without MTLA. Patients were followed up with clinical and cognitive assessments over a 3-year period. RESULTS: Three years after stroke, 34 patients (23.6%) had developed new-onset dementia. The cumulative proportion of survivors without dementia was 57.6% in patients with MTLA and 80.8% in patients without MTLA (P =.02). The unadjusted relative risk of poststroke dementia associated with MTLA was 2.3 (95% confidence interval, 1.1-4.7). However, using the Cox proportional hazards model, MTLA did not seem to be an independent predictor of poststroke dementia. Independent predictors of poststroke dementia were increasing age, diabetes mellitus, severity of the clinical deficit at admission, and severity of leukoaraiosis on computed tomography. CONCLUSIONS: Patients who had a stroke and MTLA more frequently develop dementia than patients without MTLA, but our study does not suggest that MTLA independently contributes to dementia. A longer follow-up may be necessary to reevaluate the influence of MTLA.

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↗

PubMed2002

Aneurysms of the anterior communicating artery treated with Guglielmi detachable coils: follow-up with contrast-enhanced MR angiography.

BACKGROUND AND PURPOSE: The long-term outcome of patients treated with Guglielmi detachable coils (GDCs) remains unknown and is being evaluated. We sought to assess the feasibility and utility of contrast-enhanced MR angiography in the follow-up of anterior communicating artery (AcomA) aneurysms treated with GDCs. METHODS: In a prospective study, 20 consecutive patients with AcomA aneurysms underwent digital subtraction angiography (DSA), time-of-flight MR angiography (TOF-MRA), and contrast-enhanced MR angiography (MRA) 12 months after treatment with GDCs. The aneurysmal sac measured less than 10 mm in 19 patients and 12 mm in one patient. Two observers who did not analyze the DSA images independently reviewed the MRA images. Aneurysms were classified according to the presence of a residual neck (ie, complete occlusion, small residual neck, large residual neck, or not assessable). DSA was used as the standard of reference. RESULTS: Images from all examinations were assessable. Venous enhancement was observed in five cases at contrast-enhanced MRA; this did not affect image interpretation. Interobserver agreement was good. A comparison of the techniques showed good agreement in the detection of a residual neck. Two cases of a small residual neck were not detected at TOF-MRA, and one case of complete occlusion was misclassified as a small residual neck at contrast-enhanced MRA. CONCLUSION: Our findings showed that contrast-enhanced MRA is a valuable method for the follow-up of aneurysms in the AcomA after their treatment with GDCs. Further studies with multiple aneurysm locations and larger groups are required to determine the exact role of this technique.

Adolescent↗

PubMedDate not supplied

Endovascular treatment of peripheral cerebellar artery aneurysms.

BACKGROUND AND PURPOSE: Peripheral cerebellar artery aneurysms are rare and difficult to treat surgically. We report the angiographic results and the clinical outcomes for eight patients treated by embolization for peripheral cerebellar artery aneurysms. METHODS: Between 1994 and 2001, eight patients with peripheral cerebellar artery aneurysms were referred from the neurosurgery department for endovascular treatment. The patients consisted of four women and four men with a mean age of 43 years (range, 16-68 years). Seven patients presented with subarachnoid hemorrhage. In one patient, the aneurysm was incidental. In five cases, selective embolization of the aneurysmal sac was performed using GDCs. Two large peripheral cerebellar artery aneurysms and one small aneurysm with a wide neck were treated by parent vessel occlusion. Mean clinical and imaging follow-up duration was 18.5 months (range, 12-36 months). RESULTS: Endovascular treatment resulted in five complete occlusions, two neck remnants, and one residual aneurysmal flow. Clinical evaluation showed that good or excellent recovery was achieved by all patients. Imaging follow-up revealed seven complete occlusions and one residual aneurysmal flow. CONCLUSION: Our study showed that the endovascular approach to treat peripheral cerebellar artery aneurysms by selective embolization or parent vessel occlusion was feasible, safe, and effective. Imaging follow-up showed excellent anatomic results in accordance with clinical recovery.

Adolescent↗

PubMedDate not supplied

Three-dimensional packing with complex orbit coils for the endovascular treatment of intracranial aneurysms.

BACKGROUND AND PURPOSE: Endovascular treatment of intracranial aneurysms is too often associated with aneurysm recurrence due to coil compaction. High packing of coils prevents compaction. To increase the packing attenuation, we sought to evaluate the results of selective embolization of aneurysms with complex-shaped coils alone. METHODS: Twenty consecutive patients with an intracranial aneurysm were treated by selective embolization. There were 12 women and eight men, with a mean age of 48 years. Fourteen patients presented with subarachnoid hemorrhage, whereas six were asymptomatic. Mean size of aneurysms was 5 mm (range, 3-11 mm). In all cases, we tried to pack the aneurysm with complex coils only (Orbit, Cordis, Miami Lakes, FL), delivered in a concentric fashion. Remodeling technique was used in two cases of wide-neck aneurysms. Clinical and anatomic outcome were assessed by using the modified Glasgow outcome scale and 6-month MR angiography (MRA). RESULTS: From two to five complex coils were delivered within the aneurysms. Occlusion by using complex coils alone was successful in 16 patients, and resulted in 14 complete occlusions and two neck remnants. In four patients, additional helical Orbit coils or Guglielmi detachable coils were required to complete aneurysm obliteration. No technical complication occurred, and clinical outcome was excellent in 14 cases and good in two. Follow-up MRAs were obtained in all patients and showed only one slight recanalization. CONCLUSIONS: Intracranial aneurysms may be treated by selective embolization with complex coils only. Imaging follow-up at 6 months shows a low rate of coil compaction.

Adult↗

PubMedDate not supplied

Three-dimensional dynamic MR digital subtraction angiography using sensitivity encoding for the evaluation of intracranial arteriovenous malformations: a preliminary study.

BACKGROUND AND PURPOSE: Our aim was to develop 3D dynamic MR digital subtraction angiography with high temporal resolution without sacrificing spatial resolution by using sensitivity encoding for the evaluation of cerebral arteriovenous malformations. METHODS: Nineteen patients with 19 angiographically proven arteriovenous malformations (16 supratentorial and 3 infratentorial) were assessed by conventional catheter angiography and 3D dynamic MR digital subtraction angiography. A 3D contrast-enhanced gradient-echo sequence with sensitivity encoding based on a parallel imaging technique was performed and acquired 20 dynamic images, repeated 18 times every 1.7 seconds. Three-dimensional dynamic MR digital subtraction angiograms were analyzed independently by two radiologists in a blinded fashion with regard to arteriovenous malformation nidus and venous drainage. Conventional catheter angiography was used as reference. RESULTS: All MR imaging examinations were assessable. Interobserver agreement was excellent for the detection of nidus and for the evaluation of nidus size (kappa = 1 and 0.875, respectively) but moderate for the visualization of the venous drainage (kappa = 0.56). All nidi detected on conventional catheter angiography were clearly depicted on 3D dynamic MR digital subtraction angiography. The evaluation of the size of the nidus by both techniques was similar. On 3D dynamic MR angiograms, veins were correctly analyzed in 17 of 19 arteriovenous malformations. CONCLUSION: Our preliminary study demonstrates that 3D dynamic MR digital subtraction angiography using sensitivity encoding with a high spatial resolution is appropriate for the assessment of arteriovenous malformations.

Adult↗