Effectiveness of computed tomography perfusion imaging in stroke management.

Objectives: Current guidelines do not support the use of computed tomography perfusion (CTP) in stroke, except when identifying the penumbra during an extended treatment window. Therefore, this study aimed to define the yield of CTP in diagnosing a stroke diagnosis beyond the imaging of the penumbra in the hyperacute phase (0-6 h) and an extended time window (6-24 h). Materials and methods: All consecutive patients with acute onset of symptoms within a 24-h window underwent CTP imaging. The diagnostic value of CTP was calculated against the clinical and radiological diagnoses of stroke. A positive CTP result was determined by the presence of either a core or penumbra on the RAPID summary. Clinical diagnoses corresponded to discharge diagnoses of stroke. A radiological diagnosis was established if early ischemic changes [Alberta Stroke Program Early CT Score (ASPECTS) <10] were observed on the baseline CT scan, acute infarction was confirmed on follow-up imaging, or symptomatic occlusion was evident on baseline CTA. Results: Between November 2018 and November 2019, 585 consecutive patients with an acute neurological deficit underwent multimodal CT imaging. A total of 500 patients (85%) were included, where 274 (55%) were within the hyperacute phase, 153 (31%) had a radiological diagnosis of stroke, and 122 (24%) had a clinical diagnosis of stroke. CTP yielded positive results only in patients with a confirmed stroke (positive predictive value and specificity of 100%). When CTP results were negative, 43% of the cases turned out to stroke mimics. Patients with stroke mimics were younger (66 ± 17 vs. 73 ± 13) and had lower scores on the National Institutes of Health Stroke Scale [median 0; interquartile range (IQR) 0-2 vs. median 4; IQR 2-6] compared to patients with CTP-negative strokes. Conclusion: In our study, CTP consistently indicated brain ischemia; therefore, in stroke management, CTP is most beneficial when it yields a positive result. A positive CTP result should prompt adequate stroke management actions without any delay. Conversely, a negative CTP result necessitates the consideration of both stroke and non-stroke diagnoses.

Cerebral air embolism: neurologic manifestations, prognosis, and outcome.

Background: Cerebral air embolism (CAE) is an uncommon medical emergency with a potentially fatal course. We have retrospectively analyzed a set of patients treated with CAE at our comprehensive stroke center and a hyperbaric medicine center. An overview of the pathophysiology, causes, diagnosis, and treatment of CAE is provided. Results: We retrospectively identified 11 patients with cerebral venous and arterial air emboli that highlight the diversity in etiologies, manifestations, and disease courses encountered clinically. Acute-onset stroke syndrome and a progressive impairment of consciousness were the two most common presentations in four patients each (36%). Two patients (18%) suffered from an acute-onset coma, and one (9%) was asymptomatic. Four patients (36%) were treated with hyperbaric oxygen therapy (HBTO), high-flow oxygen therapy without HBOT was started in two patients (18%), two patients (18%) were in critical care at the time of diagnosis and three (27%) received no additional treatment. CAE was fatal in five cases (46%), caused severe disability in two (18%), mild disability in three (27%), and a single patient had no lasting deficit (9%). Conclusion: Cerebral air embolism is a dangerous condition that necessitates high clinical vigilance. Due to its diverse presentation, the diagnosis can be missed or delayed in critically ill patients and result in long-lasting or fatal neurological complications. Preventative measures and a proper diagnostic and treatment approach reduce CAE's incidence and impact.

Penumbral Rescue by normobaric O = O administration in patients with ischemic stroke and target mismatch proFile (PROOF): Study protocol of a phase IIb trial.

RATIONALE: Oxygen is essential for cellular energy metabolism. Neurons are particularly vulnerable to hypoxia. Increasing oxygen supply shortly after stroke onset could preserve the ischemic penumbra until revascularization occurs. AIMS: PROOF investigates the use of normobaric oxygen (NBO) therapy within 6 h of symptom onset/notice for brain-protective bridging until endovascular revascularization of acute intracranial anterior-circulation occlusion. METHODS AND DESIGN: Randomized (1:1), standard treatment-controlled, open-label, blinded endpoint, multicenter adaptive phase IIb trial. STUDY OUTCOMES: Primary outcome is ischemic core growth (mL) from baseline to 24 h (intention-to-treat analysis). Secondary efficacy outcomes include change in NIHSS from baseline to 24 h, mRS at 90 days, cognitive and emotional function, and quality of life. Safety outcomes include mortality, intracranial hemorrhage, and respiratory failure. Exploratory analyses of imaging and blood biomarkers will be conducted. SAMPLE SIZE: Using an adaptive design with interim analysis at 80 patients per arm, up to 456 participants (228 per arm) would be needed for 80% power (one-sided alpha 0.05) to detect a mean reduction of ischemic core growth by 6.68 mL, assuming 21.4 mL standard deviation. DISCUSSION: By enrolling endovascular thrombectomy candidates in an early time window, the trial replicates insights from preclinical studies in which NBO showed beneficial effects, namely early initiation of near 100% inspired oxygen during short temporary ischemia. Primary outcome assessment at 24 h on follow-up imaging reduces variability due to withdrawal of care and early clinical confounders such as delayed extubation and aspiration pneumonia. TRIAL REGISTRATIONS: ClinicalTrials.gov: NCT03500939; EudraCT: 2017-001355-31.

Acute Isolated Central Facial Palsy as Manifestation of Middle Cerebral Artery Ischemia.

BACKGROUND: Isolated central facial palsy (I-CFP) is attributed to a lacunar syndrome affecting the corona radiata region or pons. We examined our acute stroke registry for patients presenting with I-CFP and localized their symptoms to a vascular lesion. SUBJECT & METHODS: Our database of consecutive patients with symptoms of acute cerebral ischemia admitted from January 2008 to December 2012 was reviewed for NIH Stroke Scale (NIHSS) scores and subcomponents. All patients with I-CFP ± dysarthria (total NIHSS ≤ 3) had contrast-enhanced MR-angiography and transcranial Doppler as standard of care. All ischemic lesions were localized by MRI within 72 hours from symptom onset. RESULTS: Of 2,202 patients with acute cerebral ischemia, 879 patients (35%) had NIHSS score ≤ 3 points (mean age 63 + 15 years, 46 % women). Nine patients (.4%) presented with I-CFP ± dysarthria. Of these, only 1 had a lesion in the corona radiata and patent MCA, 1 had a pontine lesion without proximal vessel occlusion (2/9, or 22%). Remaining 7 patients (78%) had flow-limiting thromboembolic mid-to-distal M1/proximal M2 MCA disease. Of these, 6 (86%) patients had a prominent early anterior temporal artery on MRA and nonlacunar ischemic lesions on MRI. CONCLUSIONS: Contrary to current teaching of lesion localization for an I-CFP, our study revealed the majority of acute patients presenting with this symptom had evidence of flow-limiting thromboembolic MCA disease rather than a lacunar lesion. Our findings underscore the essential role of comprehensive vascular imaging in patients presenting with I-CFP, which is commonly associated with acute flow-limiting thromboembolic MCA disease.

Factors influencing door-to-imaging time: analysis of the safe implementation of treatments in Stroke-EAST registry.

BACKGROUND: Brain imaging is logistically the most difficult step before thrombolysis. To improve door-to-needle time (DNT), it is important to understand if (1) longer door-to-imaging time (DIT) results in longer DNT, (2) hospitals have different DIT performances, and (3) patient and hospital characteristics predict DIT. METHODS: Prospectively collected data in the Safe Implementation of Treatments in Stroke-EAST (SITS-EAST) registry from Central/Eastern European countries between 2008 and 2011 were analyzed. Hospital characteristics were obtained by questionnaire from each center. Patient- and hospital-level predictors of DIT of 25 minutes or less were identified by the method of generalized estimating equations. RESULTS: Altogether 6 of 9 SITS-EAST countries participated with 4212 patients entered into the database of which 3631 (86%) had all required variables. DIT of 25 minutes or less was achieved in 2464 (68%) patients (range, 3%-93%; median, 65%; and interquartile range, 50%-80% between centers). Patients with DIT of 25 minutes or less had shorter DNT (median, 60 minutes) than patients with DIT of more than 25 minutes (median, 86 minutes; P < .001). Four variables independently predicted DIT of 25 minutes or less: longer time from stroke onset to admission (91-180 versus 0-90 minutes; odds ratio [OR], 1.6; 95% confidence interval [CI], 1.3-1.8), transport time of 5 minutes or less (OR, 2.9; 95% CI, 1.7-4.7) between the place of admission and a computed tomography (CT) scanner, no or minimal neurologic deficit before stroke (OR, 1.3; 95% CI, 1.02-1.5), and diabetes mellitus (OR, .8; 95% CI, .7-.97). CONCLUSIONS: DIT should be improved in patients arriving early and late. Place of admission should allow transport time to a CT scanner under 5 minutes.

Intravenous thrombolysis in acute ischemic stroke: standard and potential future applications.

Acute ischemic stroke is a medical emergency requiring urgent treatment. Randomized clinical trial and Phase IV data have provided unequivocal evidence that intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) improves early functional outcomes by restoring brain perfusion. Moreover, these studies have shed substantial light on the factors which are associated with more favorable outcome with tPA and are related to the highest benefit-to-risk ratio. Stroke physicians should consider vascular imaging techniques to aid decision making with thrombolytic therapy. The presence of intracranial occlusion is the target of treatment with early recanalization being the goal. Successful use of intravenous thrombolysis depends on a sound understanding of the decision-making process and organization of the treating team who strives for early treatment initiation and strict adherence to the protocol. Intravenous rt-PA within 4.5 h of onset should now be a standard treatment of acute disabling ischemic stroke throughout the world. This review also summarizes intravenous thrombolysis contraindications as well as the safety of novel reperfusion therapies including tenecteplase, sonothrombolysis and the combination of alteplase with direct thrombin inhibitors or glycoprotein IIb/IIIa receptor antagonists.

Intravenous thrombolysis for acute ischemic stroke occurring during hospitalization for transient ischemic attack.

BACKGROUND: There are limited data regarding the use of intravenous thrombolysis in patients who experienced acute ischemic symptoms during their hospitalization for prior transient ischemic attack. AIM: We sought to prospectively evaluate the safety and efficacy of intravenous thrombolysis for the treatment of acute ischemic stroke occurring during hospitalization for transient ischemic attack in an international, multicenter study. METHODS: Consecutive patients with acute ischemic stroke that occurred during hospitalization for prior transient ischemic attack were treated with intravenous thrombolysis in five tertiary-care stroke centers. Early arterial recanalization was determined by transcranial Doppler at the end of recombinant tissue plasminogen activator infusion using previously validated criteria. Symptomatic intracranial hemorrhage complicating intravenous thrombolysis was evaluated using the National Institute of Neurological Disorders and Stroke Recombinant Tissue Plasminogen Activator Stroke Study definition. Functional independence at three-months was defined as Modified Rankin Scale score of 0-2. RESULTS: Systemic recombinant tissue plasminogen activator infusion (median onset-to-treatment time 70 mins, interquartile range 50-150) was given in 25 consecutive patients (mean age 66 ± 10 years) who developed acute ischemic stroke symptoms (median National Institutes of Health Stroke Scale score 10 points; interquartile range 8-14) during hospitalization for prior transient ischemic attack (median ABCD(2) score 5 points; median time-to-symptom recurrence 24 h, interquartile range 24-48). No symptomatic intracranial hemorrhage (0%; 95% confidence interval 0-12%) was documented. Early complete recanalization occurred in 64% of patients (95% confidence interval 44-80%), and 84% (95% confidence interval 65-94%) achieved three-month functional independence. The rate of three-month functional independence was higher in patients treated with intravenous tissue plasminogen activator within 90 mins from symptom onset compared with those with onset-to-treatment time>90 mins (81% vs. 33%; P = 0.031). CONCLUSIONS: Intravenous thrombolysis for symptoms of acute ischemic stroke occurring after hospitalization for transient ischemic attack appears to be safe. These pilot data support resetting the clock if new symptoms recur shortly after transient ischemic attack.