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L Derex

Publications and source records attributed to L Derex.

At least 37 records · Page 2Linked to original sources

Baseline magnetic resonance imaging parameters and stroke outcome in patients treated by intravenous tissue plasminogen activator.

BACKGROUND AND PURPOSE: We designed a prospective sequential pretreatment and posttreatment MRI study to assess the relation between neuroimaging parameters and clinical outcome in patients treated with intravenous recombinant tissue-type plasminogen activator (rtPA). METHODS: Patients with symptoms of acute hemispheric ischemic stroke were recruited. The National Institutes of Health Stroke Scale (NIHSS) score was assessed at baseline and at days 1, 7, and 60, and the modified Rankin scale (mRS) at day 60, by which outcome was classified in terms of independence (mRS score 0, 1, or 2) or severe disability or death (mRS score 3 through 6), was assigned. Multimodal stroke MRI was performed at presentation and repeated at day 1. MRI procedures included magnetic resonance angiography, T2* gradient-echo sequence, echoplanar imaging, and isotropic diffusion- (DWI) and perfusion-weighted (PWI) imaging. Patients were treated with intravenous rtPA after MRI completion. RESULTS: Twenty-nine patients (16 men and 13 women; mean+/-SD age, 65+/-14 years) underwent MRI; the mean time from symptom onset to treatment was 255+/-62 minutes. Twenty-six patients had a vessel occlusion, and 15 patients experienced a partial (Thrombolysis in Myocardial Infarction [TIMI]-2) or total (TIMI-3) recanalization at day 1, whereas 11 patients had a persistent occlusion. Mean NIHSS scores at day 60 were 5.7+/-5.4 if recanalization had occurred and 14+/-2 in cases of persistent occlusion. According to the mRS, 13 patients were independent (mRS 0 through 2), whereas severe disability or death (mRS 3 through 6) was observed in 15 patients. A better outcome was observed when recanalization was achieved (r=-0.68, P=0.0002). PWI volume and time to peak (TTP) within the DWI lesion assessed before therapy were correlated with day-60 NIHSS score (PWI volume: r=0.51, P=0.006, TTP: r=0.35, P=0.07). The day-0 DWI abnormality volume was well correlated with day-60 NIHSS score (r=0.58, P=0.001). Multiple regression linear analysis showed that 2 factors mainly influenced clinical outcome: (1) recanalization, with a high correlation with NIHSS score at day 60 (P=0.0001) and (2) day-0 DWI lesion volume, which is closely associated with day-60 NIHSS score (P=0.03). CONCLUSIONS: Baseline DWI volume and recanalization are the main factors influencing clinical outcome after rtPA for ischemic stroke.

Acute Disease↗

[Cerebral amyloid angiopathy revealed by transient ischemic events: contribution of MRI to diagnosis and pathophysiology study].

We report the case of a 72-year-old left-handed woman presenting with episodes of paresthesias of the left arm and dysarthria consistent with transient ischemic attacks. The diffusion MRI showed hypersignals of the right corona radiata suggesting recent ischemic process whereas gradient-echo MRI revealed multiple small hypointense regions consistent with petechial hemorrhages restricted to the corticosubcortical regions. Gadolinium-enhanced, T1-weighted MRI showed focal meningeal enhancement. The diagnosis of cerebral amyloid angiopathy was supported by leptomeningeal biopsy. The association of ischemic suffering, petechial haemorrhage and meningeal enhancement as demonstrated by multisequence MRI highly suggest a cerebral amyloid angiopathy.

Aged↗

The delayed perfusion sign at MRI.

PURPOSE: Effective collateral blood flow seem to be an important factor associated with a small infarct volume and a good clinical outcome. We aimed to assess leptomeningeal collateral blood flow on source perfusion-weighted images in patients with acute stroke. MATERIALS AND METHODS: 29 patients with proximal middle cerebral artery occlusion (MCA alone, n=17; MCA + internal carotid artery [ICA] occlusion, n=12) were evaluated with MRI at baseline before thrombolytic therapy, and at day 60. Clinical evaluation was performed at days 0 and 60 with the National Institutes of Health Stroke Scale (NIHSS) score, and at day 60 with the modified Rankin score. We assessed (on source images of the dynamic contrast-enhanced T2*-weighted perfusion [PWI] sequence) the presence of a hypointensity consistent with delayed contrast arrival within the global perfusion deficit (delayed perfusion sign). We analyzed the extent of the area demonstrating such delayed perfusion (DP area) on source images of the PWI sequence, and compared it with the global perfusion (GP) abnormality shown by time-to-peak maps. We calculated the Spearman rank correlation coefficient between the DP/GP ratio and: 1. age; 2. clinical scores; 3. site of occlusion [MCA alone versus ICA+MCA occlusion]; 4. DWI lesion size at day 0, and T2WI lesion size at day 60; 5. PWI-derived parameters (time-to-peak [TTP], relative cerebral blood volume [rCBV], relative cerebral blood flow [rCBF], and peak height). All tests were bilateral and a p value<0.05 was considered as significant. RESULTS: Delayed perfusion areas of various size were found within the global perfusion deficit in all patients. High DP/GP ratio values were significantly correlated with: 1. better clinical scores at day 0 and day 60 (all p<=0.04); 2. smaller lesions at day 0 DWI and at day 60 T2WI (all p<=0.004); 3. ICA patency (r=0.49, p=0.01); 4. lower TTP delays, and higher values of rCBV, rCBF, and peak height. CONCLUSION: These preliminary data suggest that a delayed contrast filling observed on native perfusion-weighted images may be a marker of leptomeningeal collateral blood flow, and may lead to better clinical and morphological outcomes in acute ischemic stroke.

Acute Disease↗

Early detection of cerebral arterial occlusion on magnetic resonance angiography: predictive value of the baseline NIHSS score and impact on neurological outcome.

The presence of a thrombus on initial arteriography is directly related to the baseline NIHSS score. Magnetic resonance angiography (MRA) offers a noninvasive and rapid assessment of large cerebral vessel patency. We aimed at evaluating (1) the baseline NIHSS score as a tool for predicting the likelihood of an occluded artery on MRA and (2) the course of stroke within the first week according to the presence of a cerebral arterial occlusion. Patients were enrolled in this prospective study according to the following criteria: (1) acute cerebral ischemia with a neurological deficit lasting >1 h, and (2) brain MRI performed within 24 h of stroke onset. The NIHSS score assessment was performed on admission and at day 1 and day 7. The MRI protocol included: (1) T2-weighted Turbo spin echo, (2) echo-planar imaging isotropic diffusion, (3) T2*-gradient echo sequence, and (4) time of flight MRA (3D TOF Turbo MRA). The presence of a symptomatic cerebral arterial occlusion on MRA was systematically screened. Fifty-four patients were studied. Median age was 60 years. Mean time from stroke onset to NIHSS assessment was 170 +/- 95 min. The mean baseline NIHSS score was 13.5 +/- 7.3. The mean time from stroke onset to MRI was 384 +/- 171 min. MRA was readable in 50 cases. An arterial occlusion was detected in 23 patients (46%). The median baseline NIHSS score was significantly higher in the group of patients with occlusion than in the group of patients without occlusion (18 vs. 7, p = 0.01). The predictive probability to demonstrate an arterial occlusion was related to the baseline NIHSS score. None of the patients with an NIHSS score of 1-6 (11 patients) had visible occlusion, whereas 9 (43%) out of 21 patients with an NIHSS score of 7-15 and 14 (78% ) out of 18 patients with an NIHSS score above 16 had an arterial occlusion. For an increase by one point in the NIHSS score, the odds ratio for the presence of occlusion was 1.28 (95% CI: 1.11-1.46). The course of the stroke as assessed by follow-up NIHSS score was significantly more severe if an occlusion was detected. Median day 0, day 1 and day 7 NIHSS score were, respectively, 18, 16 and 13 in patients who had an occlusion versus 7, 4 and 0 in patients who had no visible occlusion (p < 0.01). A direct relation between the baseline NIHSS score and the likelihood of the presence of an occlusion on initial MRA is demonstrated. The presence of a cerebral arterial occlusion on MRA is significantly linked to a poor neurological outcome.

Adult↗

Old microbleeds are a potential risk factor for cerebral bleeding after ischemic stroke: a gradient-echo T2*-weighted brain MRI study.

BACKGROUND AND PURPOSE: T2*-weighted gradient-echo MRI is known to detect old microbleeds (MBs), considered indicative of microangiopathy. MBs might be a potential risk factor for early cerebral bleeding (CB) after ischemic stroke. Therefore, we assessed the impact of MBs on the occurrence of CB after cerebral infarction. METHODS: We included prospectively stroke patients who had documented ischemic damage. The imaging protocol involved baseline CT scan, T2*-weighted gradient-echo MRI, diffusion-weighted imaging, T2-weighted imaging, and magnetic resonance angiography and had to be performed within 24 hours after symptom onset. The assessment of CB with T2*-weighted gradient-echo sequence necessitated a focal area of signal loss either within the ischemic area revealed by diffusion-weighted imaging or remote from it. Old MBs were defined on T2*-weighted images as homogeneous rounded areas of signal loss without surrounding edema. CT scan was systematically repeated within the first week to verify CB as diagnosed by the T2* weighted sequence. RESULTS: One hundred patients (mean age, 60 +/- 13 years; range, 19 to 83 years; 58 men, 42 women) met the inclusion criteria. MBs were seen in 20 patients on T2*-weighted imaging. Multivariate logistic regression analysis revealed that age, diabetes, previous use of antithrombotic drugs, evidence of an atherothrombotic source of stroke, and lacunar infarct were significantly associated with MBs (P<0.0001). CB was diagnosed in 26 patients: at the acute stage by T2*-gradient echo sequence in 18 patients and with CT scan performed within the first week in 8 patients. Multivariate logistic regression analysis showed that baseline National Institutes of Health Stroke Scale score, diabetes, and MBs were considered significant and independent predictors of CB (P<0.001). CONCLUSIONS: Although the pathogenesis of CB after ischemic stroke is multifactorial, the increased observation of CB in patients with MBs suggests that the associated vascular vulnerability contributes to CB.

Adult↗

[Anterior choroidal artery infarction revealing polyarteritis nodosa].

An 81-year old man presented with a sudden right ataxic hemiparesis. Brain CT scan showed a left anterior choroidal artery territory infarction. Biological signs of inflammation were present without any evidence of infection or neoplasm. The patient's clinical status deteriorated with fever, loss of weight and confusion. Muscle biopsy showed characteristic abnormalities of polyarteritis nodosa (PAN). Oral corticosteroids plus monthly pulse intravenous cyclophosphamide were started. A rapid clinical improvement was observed as well as the resolution of inflammation within one month. Twenty months later, the patient had recovered normal cognitive function and was able to carry out all usual activities. We describe the CNS complications of PAN and the therapeutic options.

Aged↗

[Vertebro-basilar ischemic strokes and aseptic meningitis, late complications of Fabry's disease].

Fabry's disease, also called angiokeratoma corporis diffusum universal, is a rare cause of stroke in the young. We report the case of a 39-year-old man who presented with relapsing vertebro-basilar ischemic strokes. Biological tests showed the presence of an aseptic meningitis and a biological inflammatory syndrome, suggesting a particularly progressive illness. The possible mechanisms involved in this exceptional association are discussed.

Adult↗

[Necrosis of a hypophyseal adenoma and ischemic cerebral vascular accident ].

A 78-year old man developed an acute intracranial hypertension followed by central left facial palsy. CT Scan and MRI revealed an ischemia within the right lenticulostriate arteries territory and a hemorrhagic infarction of a pituitary adenoma without extrinsic carotid artery compression. Neuroophthalmologic examination and hormonal screening were normal. Though pituitary apoplexy and stroke might represent a fortuitous association, several mechanisms underlying such clinical picture are advanced.

Adenoma↗

Thrombolytic therapy in acute ischemic stroke patients with cardiac thrombus.

The authors describe the outcome of five patients with a cardiac thrombus selected among 183 patients with stroke (2.7 %) who were given IV tissue plasminogen activator (tPA). No early systemic or cerebral embolism occurred. Two patients made a complete recovery at 3 months. Two patients had a moderate outcome. One patient had late recurrent cerebral embolism and died. These data suggest that the presence of a cardiac thrombus is not associated with a high risk of recurrent embolism in patients with stroke who are given IV tPA.

Aged↗

MRI of acute post-ischemic cerebral hemorrhage in stroke patients: diagnosis with T2*-weighted gradient-echo sequences.

The use of T2*-weighted sequences has been advocated for early differentiation between hematoma and ischemia in patients with acute stroke. Early hemorrhagic transformation of ischemic stroke is an adverse event which may occur under treatment and may impair the prognosis: our aim is to evaluate the ability of T2*-weighted gradient-echo sequence (T2* GRE) to detect post-ischemic cerebral hemorrhage. The imaging procedure included: (1) baseline CT scan at admission. (2) MRI performed within 24 h of therapy onset including: (a) dual fast spin echo T2 sequence, (b) axial isotropic echoplanar diffusion-weighted imaging sequence, (c) conventional T2* GRE, and (d) 3D TOF turbo MRA. Post-ischemic cerebral hemorrhage was diagnosed if T2* GRE detected a focal intraparenchymal area of signal loss. The diameter of this lesion had to be more than 5 mm in order to eliminate past microbleeds. (3) Patients who showed an early suspicion of bleeding on MRI promptly had a second CT scan, and, if this one was negative for bleeding, another CT scan was performed 1 day later. All the other patients had a control CT scan during the first week. Forty-five consecutive patients have been included. T2* GRE showed intracranial bleeding in seven. The diagnosis of post-ischemic cerebral bleeding was confirmed by CT in all patients. Control CT scans did not reveal any post-ischemic cerebral hemorrhage in patients with negative MRI. In one case, hemorrhage was seen earlier on MRI than on CT scan. In conclusion, T2* GRE appeared to be at least as efficient as CT scan in the detection of early post-ischemic cerebral hemorrhage.

Acute Disease↗

Early diagnosis of hemorrhagic transformation: diffusion/perfusion-weighted MRI versus CT scan.

UNLABELLED: Standard magnetic resonance imaging (MRI) techniques failed to image adequately acute hemorrhagic transformation (HT). Therefore, computed tomography (CT) is still needed to exclude intracerebral hemorrhage. New MRI techniques such as diffusion- and perfusion-weighted imaging (DWI and PWI) may improve the early detection of HT. The utility of this approach requires a direct comparison of the sensitivity of CT with these MRI techniques. METHODS: Nine patients experienced an acute carotid artery territory ischemic stroke diagnosed on a first CT performed 3.8 +/- 2 h after the onset of stroke. They underwent a second CT 12 +/- 4 h after the onset of stroke, followed 35 +/- 10 min later by an MRI protocol including: (1) an axial isotropic DWI SE echo-planar imaging (EPI) sequence; (2) time of flight MR angiography (TOF MRA); (3) PWI with an axial T(2)*-weighted gradient echo EPI sequence using 20 ml gadolinium contrast agent (Gd-DTPA); HT was characterized on DWI SE EPI as a heterogeneous area of signal loss within the ischemic area; (4) at day 7, CT was also performed in all patients who had an early suspicion of bleeding according to MRI. RESULTS: An HT was detected exclusively with CT in 1 out of 9 patients, while an MRI pattern of HT was found in 6 out of 9 patients. In 5 of these 6 patients, the CT scan did not show an obvious pattern of HT. Day 7 CT confirmed HT in all patients who had early suspicion of bleeding according to DWI criteria. CONCLUSION: This study suggests that new MRI techniques may allow an early detection of HT, thus improving the management of stroke.

Adult↗

Outcome of stroke patients without angiographically revealed arterial occlusion within four hours of symptom onset.

BACKGROUND AND PURPOSE: Follow-up imaging data from stroke patients without angiographically apparent arterial occlusions at symptom onset are lacking. We reviewed our Emergency Management of Stroke (EMS) trial experience to determine the clinical and imaging outcomes of patients with ischemic stroke who showed no arterial occlusion on angiograms obtained within 4 hours of symptom onset. METHODS: All patients in this report were participants in the EMS trial that was designed to address the safety and potential efficacy of combined IV and intraarterial thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA) in patients with acute ischemic stroke. RESULTS: Thirty-five patients were randomized to receive either IV rt-PA (n = 17) or placebo (n = 18), followed by cerebral angiography. No symptomatic arterial occlusion was evident in 10 (29%) of the 34 patients. Eight (80%) of 10 patients without angiographically apparent clot within 4 hours of symptom onset had a new cerebral infarction confirmed on follow-up brain imaging. The median 72-hour infarction volume was 2.4 cc (range, 1-30 cc). Four of the 10 "no-clot" patients had a favorable 3-month outcome as assessed by Barthel Index (score, 95 or 100) and modified Rankin Scale (score, 0 or 1). The six remaining patients had 3-month Rankin Scale scores of 1 (Barthel of 90), 2, 3, 4, or 5. CONCLUSION: Acute ischemic stroke patients with a neurologic deficit but a negative angiogram during the first 4 hours after symptom onset usually develop image-documented cerebral infarction, and approximately half suffer from long-term functional disability. The two most likely explanations for negative angiograms are very early irreversible ischemic damage despite recanalization or ongoing ischemia secondary to clot in non-visible penetrating arterioles or in the microvasculature.

Aged↗

Intravenous tPA in acute ischemic stroke related to internal carotid artery dissection.

The authors describe the outcomes in 11 patients who had acute ischemic stroke related to internal carotid artery (ICA) dissection and were treated with IV tissue plasminogen activator (tPA). One symptomatic intracerebral hemorrhage occurred 36 hours after tPA was given. The mean day 90 modified Rankin Scale (m-RS) score was 2.4 (+/-1.6). No death was observed at 3 months. Four patients of 11 (36.4%) made an excellent recovery (day 90 m-RS score: 0 to 1). This study demonstrates the feasibility of IV thrombolysis with tPA (0.8 mg/kg) in ischemic stroke related to ICA dissection within the first 7 hours.

Adult↗

rtPA intravenous thrombolysis in anterior choroidal artery territory stroke.

OBJECTIVE: To study the possible specific response to recombinant tissue plasminogen activator (rtPA) thrombolysis of anterior choroidal artery (AChA) stroke. BACKGROUND: Outcome and response after rtPA thrombolysis are possibly better in small-vessel infarcts, but a specific study of AChA stroke has not yet been performed. METHODS: The authors proposed an open trial of IV rtPA within 7 hours in patients age 20 and 81 years with all types of internal carotid artery territory stroke if the baseline Scandinavian Stroke Scale (SSS) score was less than 48. A dose of rtPA 0.8 mg/kg was infused over 90 minutes. Of 114 consecutive patients, 9 patients (7.9%) exhibited hypodensity in the AChA territory on day 1 brain CT. RESULTS: Seven of nine patients with AChA infarct had a primary early recovery within 6 hours after the initiation of rtPA infusion. In addition, recovery was complete in five patients and partial in two patients. No intracerebral hematoma was observed. Three patients had a "reinfarct syndrome" at 12, 25, and 48 hours respectively. However, in the two latter patients treated with IV heparin, the deficit disappeared again with the increase of heparin dose in one patient and disappeared spontaneously in the other patient. The overall outcome at day 90 was six total recoveries in nine patients (66%). Patients with a final good outcome had a slight "unstructured" hypodensity in the AChA territory on day 1 brain CT, whereas patients with a bad outcome had the classic "structured" hypodensity of AChA territory stroke. CONCLUSION: These data support a specific quick response of AChA territory stroke to IV rtPA thrombolysis, probably due to the small size of the artery and of the "clot." The high frequency of the reinfarct syndrome is a clinical fact that is difficult to explain. Efficient heparin treatment after 24 hours may control the reinfarct syndrome in some patients.

Aged↗

[Partial non-convulsive status epilepsy in multiple sclerosis].

This report describes the observations of two patients with a several years' history of multiple sclerosis who presented sudden neurologic impairment. The symptomatology was suggestive of a non-convulsive partial status epilepsy. The clinical presentation was a paroxysmal dysphasic phenomenon in the first case without any consciousness impairment, associated with slight right hemiparesis. Electroencephalographic investigations revealed asymmetrical patterns, left-sided slow waves and periodic lateralized epileptiform discharges (PLEDs). Antiepileptic treatments were partially effective and intravenous steroids were needed for complete recovery. For the second patient, clinical presentation was acute psychiatric symptoms with disorientation, alternating manic symptomatology and mutism. Electroencephalography showed left fronto-central rhythmic continuous slow wave and spike wave activity. Intravenous antiepileptic treatment quickly improved the symptomatology. These observations draw attention to the fact that an epileptic cause should not be ruled out when a patient with multiple sclerosis presents sudden neurologic or psychiatric impairment. An early diagnosis allows immediate antiepileptic treatment. Intravenous steroids can be added to stop seizures.

Adult↗

Early surgical treatment for supratentorial intracerebral hemorrhage: a randomized feasibility study.

BACKGROUND AND PURPOSE: The safety and the effectiveness of the surgical treatment of spontaneous intracerebral hemorrhage (ICH) remain controversial. To investigate the feasibility of urgent surgical evacuation of ICH, we conducted a small, randomized feasibility study of early surgical treatment versus current nonoperative management in patients with spontaneous supratentorial ICH. METHODS: Patients with spontaneous supratentorial ICH who presented to 1 university and 2 community hospitals were randomized to surgical treatment or best medical treatment. Principal eligibility criteria were ICH volume >10 cm(3) on baseline CT scan with a focal neurological deficit, Glasgow Coma Scale score >4 at the time of enrollment, randomization and therapy within 24 hours of symptom onset, surgery within 3 hours of randomization, and no evidence for ruptured aneurysm or arteriovenous malformation. The primary end point was the 3-month Glasgow Outcome Scale (GOS). A good outcome was defined as a 3-month GOS score >3. RESULTS: Twenty patients were randomized over 24 months, 9 to surgical intervention and 11 to medical treatment. The median time from onset of symptoms to presentation at the treating hospitals was 3 hours and 17 minutes, the time from randomization to surgery was 1 hour and 20 minutes, and the time from onset of symptoms to surgery was 8 hours and 35 minutes. The likelihood of a good outcome (primary outcome measure: GOS score >3) for the surgical treatment group (56%) did not differ significantly from the medical treatment group (36%). There was no significant difference in mortality at 3 months. Analysis of the secondary 3-month outcome measures showed a nonsignificant trend toward a better outcome in the surgical treatment group versus the medical treatment group for the median GOS, Barthel Index, and Rankin Scale and a significant difference in the National Institutes of Health Stroke Scale score (4 versus 14; P=0.04). CONCLUSIONS: Very early surgical treatment for acute ICH is difficult to achieve but feasible at academic medical centers and community hospitals. The trend toward less 3-month morbidity with surgical intervention in patients with spontaneous supratentorial ICH warrants further investigation of very early clot removal in larger randomized clinical trials.

Cerebellar Diseases↗

[Cortical thrombophlebitis and developmental venous anomalies].

Abnormal intracranial venous drainage called cerebral venous angioma is usually asymptomatic. Hemorrhages and seizures may however occur. The malformation may rarely be revealed by thrombosis. We report the case of a 25-year-old right-handed woman who developed cortical thrombophlebitis subsequent to developmental venous anomalies. After a course of anticoagulant therapy, outcome was good, demonstrating that anticoagulant therapy may be indicated in spite of the high risk of hemorrhage.

Adult↗