Evidence-based emergency medicine. Is MRI more accurate than CT in patients with suspected acute stroke?

Serum Sphingosine 1-Phosphate (S1P): A Novel Diagnostic Biomarker in Early Acute Ischemic Stroke

Background: Sphingosine 1-phosphate (S1P) is a lipid metabolite that mediates various physiological processes, including vascular endothelial cell function, inflammation, coagulation/thrombosis, and angiogenesis. As a result, S1P may contribute to the pathogenesis of stroke.

Objective: This study aimed to evaluate the diagnostic value of serum S1P in acute stroke.

Method: A total of 72 patients with ischemic stroke, 36 patients with hemorrhagic stroke, and 65 controls were enrolled. Serum S1P was detected by enzyme-linked immunosorbent assay (ELISA).

Results: Receiver operating characteristic curve analysis demonstrated that serum S1P could discriminate ischemic stroke from hemorrhagic stroke in both total population and subgroup analyses of samples obtained within 24 h of symptom onset (subgroup _{< 24h}) (area under curve, AUC_Total = 0.64, P = 0.017; AUC_{Subgroup < 24h} = 0.91, P < 0.001) and controls (AUC_Total = 0.62, P = 0.013; AUC_{Subgroup <24h} = 0.83, P < 0.001). Furthermore, S1P showed higher efficacy than high-density lipoprotein cholesterol (HDL-C) in discriminating ischemic stroke from controls in the total population (P_S1P = 0.013, P_HDL−C = 0.366) and in the subgroup analysis (i.e., <24 h; P_S1P < 0.001, P_HDL−C = 0.081). Additionally, lower serum S1P was associated with cervical artery plaques (P = 0.021) in controls and with dyslipidemia (P = 0.036) and milder neurological impairment evaluated by the National Institute of Health Stroke Scale (NIHSS, P = 0.047) in the ischemic stroke group.

Conclusions: The present study preliminarily investigated the diagnostic value of serum S1P in acute stroke. Decreased serum S1P may become a potential biomarker for early acute ischemic stroke and can indicate disease severity.

Impact on patient management of the implementation of a magnetic resonance imaging dedicated to neurological emergencies

RATIONALE, AIMS AND OBJECTIVES

Neurological emergencies consumed a high amount of resources in emergency department (ED). We aimed to study the effect of the implementation of a magnetic resonance imaging (MRI) dedicated to emergencies on the management of patients admitted in ED for neurological emergencies.

METHODS

We enrolled consecutive patients who underwent computed tomography and/or MRI for neurological disorders categorized as the suspicion of stroke and other reasons, over 2 periods that differed according to the priority access to computed tomography in the first period versus priority access to MRI in the second one. Criteria used to evaluate the effectiveness of the management were door-to-imaging time, ED length of stay, diagnostic performance, patient orientation, and length of hospitalization stay.

RESULTS

When priority access to MRI, the door-to-imaging time was 31 minutes longer (P = .005) for patients suspected of stroke or transient ischaemic attack (TIA) and 70 minutes for the others (P < .001). The ED length of stay was 42 minutes shorter (P = .013) for stroke/TIA patients and 26 minutes longer (P = .029) for other patients. The proportion of patients with stroke mimics (no stroke amongst suspected stroke/TIA) increased (16.7% vs 25.6%, P = .017) as well as discharged patients (21.6% vs 29.6%, P = .002). The proportion of patients with stroke/TIA amongst other reasons of admission remained unchanged (P = .114). The median length of hospitalization stay decreased from 9 to 7 days for the stroke/TIA patients (P = .042).

CONCLUSIONS

The implementation of a MRI optimized the quality of care and diagnostic accuracy for patients admitted in ED with a better identification of stroke mimics, avoiding unnecessarily hospitalizations. The management of stroke-TIA patients was not modified, but their length of hospital stay reduced.

The impact of installing an MR scanner in the emergency department for patients presenting with acute stroke-like symptoms

PURPOSE

We examined the impact of an MR scanner in the emergency department (ED) on ED length of stay (LOS), hospital (H) LOS, hospital admission rate, hospitalization costs, and ED re-presentation rate of patients presenting with stroke-like symptoms (SLS). We hypothesized that the ED MR would increase efficiency of patient care.

METHODS

The number of MRIs performed in the ED vs. inpatient setting, EDLOS, HLOS, hospitalization charges, admission rate, discharge diagnoses, and 30-60-day ED re-presentation rates were determined for ED patients with SLS six months before (2011) and after (2012) ED MR installation.

RESULTS

362 and 448 patients with SLS presented to the ED, and 196 and 176 patients were admitted in 2011 and 2012 respectively. In 2011, 36 (18.4%) admitted patients, and, in 2012, 68 (38.6%) had MRIs in the ED, p<0.001. In 2011, 74 (37.8%) admitted patients were diagnosed with ischemic stroke, compared to 92 (52.3%) in 2012, p=0.007. HLOS was longer and charges higher for patients with stroke. No patients returned with a confirmed diagnosis of CVA or TIA within 0-60days after being discharged from the ED with negative MR.

CONCLUSIONS

With the ED MR, more admitted patients 1) got scanned in the ED and 2) were diagnosed with stroke. Because this led to more patients on the stroke service actually suffering from strokes (and not other diagnoses), the overall HLOS and charges of patients presenting with SLS were not reduced by ED MR screening. Discharge after a negative ED MR did not incur risk of TIAs or strokes over the ensuing 60days. Therefore, not only does a dedicated MR scanner in the ED aid in the acute diagnosis of a CVA or other neurologic disorder, but it does so without the risk of under-diagnosing TIAs or evolving strokes in the presence of a negative MRI.

Relationship between the lesion location of acute ischemic stroke and early depressive symptoms in Japanese patients

BACKGROUND

Approximately one-third of stroke survivors suffer from post-stroke depression (PSD) in the acute or chronic stages. The presence of PSD in the acute stage after stroke is reportedly associated with poor patient prognosis; therefore, early recognition and treatment of PSD may alleviate these consequences. The aim of the current study was to examine the relationship between the lesion location and the presence of early depressive symptoms after acute ischemic stroke in Japanese patients.

METHODS

Our study included 421 patients who suffered from acute ischemic stroke. On the day of admission, the lesion location was determined using magnetic resonance imaging (MRI). Stroke severity was measured on the seventh day of hospitalization withat the National Institutes of Health Stroke Scale (NIHSS). On the tenth day of hospitalization, depressive symptoms were measured and functional assessments were performed with the Japan Stroke Scale (Depression Scale) (JSS-D) and functional independence measure (FIM), respectively.

RESULTS

A total of 71 subjects (16.9 %) were diagnosed with depression. According to the multiple logistic regression analysis, the infarcts located at frontal and temporal lobes were found to be a significant independent risk factor of early depressive symptoms in the acute stage of stroke.

CONCLUSIONS

Patients suffering from acute ischemic stroke, particularly in the frontal and temporal lobes, should be carefully assessed to detect and treat early depressive symptoms; such treatment may improve patient outcomes.