Marc Reichhart

Prognostic accuracy of cerebral blood flow measurement by perfusion computed tomography, at the time of emergency room admission, in acute stroke patients

The purpose of this study was to determine the prognostic accuracy of perfusion computed tomography (CT), performed at the time of emergency room admission, in acute stroke patients. Accuracy was determined by comparison of perfusion CT with delayed magnetic resonance (MR) and by monitoring the evolution of each patients clinical condition. Twenty‐two acute stroke patients underwent perfusion CT covering four contiguous 10mm slices on admission, as well as delayed MR, performed after a median interval of 3 days after emergency room admission. Eight were treated with thrombolytic agents. Infarct size on the admission perfusion CT was compared with that on the delayed diffusion‐weighted (DWI)–MR, chosen as the gold standard. Delayed magnetic resonance angiography and perfusion‐weighted MR were used to detect recanalization. A potential recuperation ratio, defined as PRR = penumbra size/(penumbra size + infarct size) on the admission perfusion CT, was compared with the evolution in each patients clinical condition, defined by the National Institutes of Health Stroke Scale (NIHSS). In the 8 cases with arterial recanalization, the size of the cerebral infarct on the delayed DWI‐MR was larger than or equal to that of the infarct on the admission perfusion CT, but smaller than or equal to that of the ischemic lesion on the admission perfusion CT; and the observed improvement in the NIHSS correlated with the PRR (correlation coefficient = 0.833). In the 14 cases with persistent arterial occlusion, infarct size on the delayed DWI‐MR correlated with ischemic lesion size on the admission perfusion CT (r = 0.958). In all 22 patients, the admission NIHSS correlated with the size of the ischemic area on the admission perfusion CT (r = 0.627). Based on these findings, we conclude that perfusion CT allows the accurate prediction of the final infarct size and the evaluation of clinical prognosis for acute stroke patients at the time of emergency evaluation. It may also provide information about the extent of the penumbra. Perfusion CT could therefore be a valuable tool in the early management of acute stroke patients.

Comparison of CT perfusion and angiography and MRI in selecting stroke patients for acute treatment

Forty-two stroke patients successively underwent perfusion CT (PCT)/CT angiography (CTA) and MRI examinations within 3 to 9 hours following symptom onset; 14 would have been suitable candidates for reperfusion treatment based on MRI findings. Correlation between PCT/CTA and MRI was excellent for infarct size, cortical involvement, and internal cerebral artery occlusion and substantial for penumbra/infarct ratio. Relying on MRI or PCT/CTA would have led to the same treatment decisions in all cases but one.

Propofol Treatment of Refractory Status Epilepticus: A Study of 31 Episodes

Summary:  Purpose: Refractory status epilepticus (RSE) is a critical medical condition with high mortality. Although propofol (PRO) is considered an alternative treatment to barbiturates for the management of RSE, only limited data are available. The aim of this study was to assess PRO effectiveness in patients with RSE.

Thrombolysis in stroke patients aged 80 years and older: Swiss survey of IV thrombolysis

This databank-based, multicenter study compared all stroke patients with IV tissue plasminogen activator aged ≥80 years (n = 38) and those <80 years old (n = 287). Three-month mortality was higher in older patients. Favorable outcome (modified Rankin scale ≤1) and intracranial hemorrhage (asymptomatic/symptomatic/fatal) were similarly frequent in both groups. Logistic regression showed that stroke severity, time to thrombolysis, glucose level, and history of coronary heart disease independently predicted outcome, whereas age did not.

The Acute STroke Registry and Analysis of Lausanne (ASTRAL) Design and Baseline Analysis of an Ischemic Stroke Registry Including Acute Multimodal Imaging

Background and Purpose— Stroke registries are valuable tools for obtaining information about stroke epidemiology and management. The Acute STroke Registry and Analysis of Lausanne (ASTRAL) prospectively collects epidemiological, clinical, laboratory and multimodal brain imaging data of acute ischemic stroke patients in the Centre Hospitalier Universitaire Vaudois (CHUV). Here, we provide design and methods used to create ASTRAL and present baseline data of our patients (2003 to 2008). Methods— All consecutive patients admitted to CHUV between January 1, 2003 and December 31, 2008 with acute ischemic stroke within 24 hours of symptom onset were included in ASTRAL. Patients arriving beyond 24 hours, with transient ischemic attack, intracerebral hemorrhage, subarachnoidal hemorrhage, or cerebral sinus venous thrombosis, were excluded. Recurrent ischemic strokes were registered as new events. Results— Between 2003 and 2008, 1633 patients and 1742 events were registered in ASTRAL. There was a preponderance of males, even in the elderly. Cardioembolic stroke was the most frequent type of stroke. Most strokes were of minor severity (National Institute of Health Stroke Scale [NIHSS] score ≤4 in 40.8% of patients). Cardioembolic stroke and dissections presented with the most severe clinical picture. There was a significant number of patients with unknown onset stroke, including wake-up stroke (n=568, 33.1%). Median time from last-well time to hospital arrival was 142 minutes for known onset and 759 minutes for unknown-onset stroke. The rate of intravenous or intraarterial thrombolysis between 2003 and 2008 increased from 10.8% to 20.8% in patients admitted within 24 hours of last-well time. Acute brain imaging was performed in 1695 patients (97.3%) within 24 hours. In 1358 patients (78%) who underwent acute computed tomography angiography, 717 patients (52.8%) had significant abnormalities. Of the 1068 supratentorial stroke patients who underwent acute perfusion computed tomography (61.3%), focal hypoperfusion was demonstrated in 786 patients (73.6%). Conclusions— This hospital-based prospective registry of consecutive acute ischemic strokes incorporates demographic, clinical, metabolic, acute perfusion, and arterial imaging. It is characterized by a high proportion of minor and unknown-onset strokes, short onset-to-admission time for known-onset patients, rapidly increasing thrombolysis rates, and significant vascular and perfusion imaging abnormalities in the majority of patients.

Aphasia in hyperacute stroke: language follows brain penumbra dynamics.

During the first few hours after onset, stroke symptoms may evolve rapidly. We studied the correlation between brain perfusion and aphasia changes during the hyperacute phase of stroke using a new technique of perfusion computed tomography (P‐CT). Using an aphasia score developed for each language modality, language was evaluated within 6 hours after onset, then sequentially during the first week. Maps of the penumbra and infarct obtained from P‐CT images and definite infarct size evaluated using T2 and diffusion‐weighted MRI (DWI) on day 3 were rated by a neuroradiologist, blinded to the clinical deficit. Within 6 hours, deficits in all language modalities were present in 13 out of 24 consecutive patients, corresponding to large anterior‐posterior perfusion deficits of the left middle cerebral artery (MCA) territory. The aphasia score correlated with a corresponding perfusion deficit in specific areas of the MCA territory, and showed significantly less improvement when the penumbra evolved toward infarction than when at least part of the penumbra was rescued. Our findings suggest a particularly good correlation between the evolution of aphasic symptoms and penumbra dynamics. Further studies on the relevance of penumbra dynamics in function‐specific brain areas to decision taking in hyperacute stroke management are required.

Early lacunar strokes complicating polyarteritis nodosa Thrombotic microangiopathy

Objective: To determine the patterns and mechanisms of polyarteritis nodosa (PAN)–associated strokes (PANAS). Background: Strokes are reputed to be rare complications of PAN and to occur at a late stage (2 to 3 years). The cause of stroke is unknown but may be related either to atherosclerosis-like occlusive vasculopathy, caused possibly by hypertension or corticosteroid (CS) use, or to vasculitic arterial occlusion. Methods: Clinical and radiologic patterns, latencies, and current therapy at onset in 15 PANAS patients (4 of the authors’ and 11 published cases) were analyzed. Results: A lacunar stroke syndrome (11/15 cases, 73%) was the most frequent stroke pattern in PANAS (multiple, small, deep infarcts in 6, [55%], pontine lacunae in 3 [27%], and leukoaraiosis in 2 [18%]), followed by pure lobar hematoma and bilateral, possibly cardioembolic, large ischemic infarcts (2 cases each). A stroke latency shorter than that previously established (within 8 months in 73% of cases; mean latency, 6.5 months) and a close relationship between the use of CS and stroke in PAN also were found. Of the 77% of first-time or recurrent lacunar strokes that developed despite CS therapy, 80% appeared within 6 months and 50% within 3 weeks of CS initiation. Conclusion: Early lacunar stroke syndrome, related to deep small- or pontine-penetrating artery thrombotic microangiopathy rather than vasculitis, was the most frequent PANAS pattern. This vasculopathy may be aggravated by corticosteroid (CS) therapy enhancement of either platelet thromboxane A2 production or arterial wall fibrosis. Thus, antiplatelet drugs in association with CS may be advisable for preventing stroke occurrence or recurrence in PAN.

Early profiles of clinical evolution after intravenous thrombolysis in an unselected stroke population.

Background Intravenous recombinant tissular plasminogen activator (rt-PA) is the only approved pharmacological treatment for acute ischaemic stroke. The authors aimed to analyse potential causes of the variable effect on early course and late outcome. Methods and results 136 patients (42% women, 58% men) treated with intravenous rt-PA within 3 h of stroke onset in an acute stroke unit over a 3-year period, were included. Early clinical profiles of evolution at 48 h were divided into clinical improvement (CI) (decrease >4 points in the National Institute of Health Stroke Scale (NIHSS)); clinical worsening (CW) (increase >4 points NIHSS); clinical worsening after initial improvement (CWFI) (variations of >4 points in the NIHSS). Patients with clinical stability (no NIHSS modification or <4 points) were excluded. The patients showed in 66.9% CI, 13.2% CW 8.1 % CWFI and 11.8% remained stable. Female sex, no hyperlipaemia and peripheral arterial disease were associated with CW. Male sex and smoking were associated with CI. Absence of arterial occlusion on admission (28.4%) and arterial recanalisation at 24 h were associated with CI. Main causes of clinical deterioration included symptomatic intracranial haemorrhage (sICH), persistent occlusion and cerebral oedema. 23.5% developed ICH, 6.6% of which had sICH. At 3 months, 15.5% had died. Mortality was increased in CW, mainly related to sICH and cerebral oedema. The outcome of CWFI was intermediate between CW and CI. Conclusions Early clinical profiles of evolution in thrombolysed patients vary considerably. Even with CI, it is critical to maintain vessel permeability to avoid subsequent CW.

Central Horner’s syndrome with contralateral ataxic hemiparesis A diencephalic alternate syndrome

Objective: To assess whether thalamic strokes presenting with a central Horner’s syndrome (HS) show specific clinicoanatomic patterns. Methods: From the Lausanne Stroke Registry (period 1993 to spring 2002), the authors selected all patients with thalamic stroke presenting with ipsilateral HS. Patients with complete infarction of the posterior cerebral artery territory, with involvement of middle cerebral artery territory or bilateral lesions, were excluded. Lesions on brain MRI were correlated with standard neuroanatomic templates. Results: Nine patients with thalamic infarction presenting with central HS were found; all showed contralateral ataxic hemiparesis (AH). Lesions involved the anterior or paramedian thalamus and extended to the hypothalamic or rostral paramedian mesencephalic area in all but one subject. Associated clinical signs included dysphasia (two patients), somnolence (six), vertical gaze paresis (two), asterixis (two), and hemihypesthesia (three). Conclusion: The alternate clinical pattern of central HS with contralateral AH is a stroke syndrome of the diencephalic-mesencephalic junction, resulting from the involvement of the common arterial supply to the paramedian/anterior thalamus, the posterior hypothalamus and the rostral paramedian midbrain.

MR pattern of hyperacute cerebral hemorrhage

Magnetic resonance (MR) pattern of cerebral hemorrhage relates mainly to the relaxation and susceptibility effects of iron‐containing hemoglobin degradation products, as well as to their intra‐ or extracellular location. The purpose of this article is to report two acute stroke patients who underwent thrombolytic therapy and developed hyperacute cerebral hemorrhage during their admission cerebral MR survey. They constitute the earliest MR appearance of hyperacute intracerebral bleeding reported in the literature, featuring increased diffusion properties and persistent susceptibility effect on perfusion‐weighted imaging (PWI)‐series. J. Magn. Reson. Imaging 2002;15:705–709.