Brain ; pathology ; Humans ; Hyponatremia ; complications ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Myelinolysis, Central Pontine ; diagnosis ; etiology ; pathology ; physiopathology ; therapy ; Osmolar Concentration ; Osmosis ; Osmotic Pressure ; Risk Factors ; Time Factors

Brain ; blood supply ; diagnostic imaging ; Brain Ischemia ; blood ; diagnosis ; diagnostic imaging ; Combined Modality Therapy ; methods ; Humans ; Male ; Middle Aged ; Monitoring, Physiologic ; Stroke ; drug therapy ; physiopathology ; Tomography, X-Ray Computed

No abstract available.
Arteries* ; Middle Cerebral Artery ; Stroke*

INTRODUCTIONTranscranial Doppler (TCD) is an established tool for the non-invasive assessment of cerebral blood flow. Since TCD results vary with the skills and experience of the sonographer, it requires validation against contrast angiography. We evaluated the diagnostic accuracy of TCD against computed tomography angiography (CTA) and the feasibility of the latter as an additional screening tool in our acute ischaemic stroke patients.

MATERIALS AND METHODSOur stroke unit manages about 700 patients annually. Acute stroke patients undergo TCD for vascular assessment of major arteries of the circle of Willis. Randomly selected acute stroke patients with significant stenosis on TCD underwent high-resolution cranial CTA with multidetector helical scanner. CTA was performed within 24 hours of TCD and images were interpreted by a neuroradiologist blinded to TCD findings. An independent neurosonologist reevaluated TCD if CTA findings were contradictory. Additional information by either modality was also noted.

RESULTSFifteen patients (12 men, mean age 61 +/- 15years) with cerebral ischaemia and moderate (>50%) stenosis in > or =1 large intracranial arterial segment on routine TCD were evaluated by CTA. Compared with 21 segments of significant stenosis on CTA, TCD showed 16 true-positive, 3 false-positive and 5 false-negative results (sensitivity: 76.2%, positive predictive value: 84.2%). In 3 cases, TCD showed findings complementary to CTA (real-time embolisation, collateral flow patterns, evidence of distal M2 branch occlusion).

CONCLUSIONTCD in our neurovascular laboratory shows a satisfactory agreement with cranial CTA in evaluating patients with cerebral ischaemia. TCD can provide additional real-time dynamic findings complementary to information provided by CTA.

Aged ; Brain Ischemia ; diagnosis ; Cerebral Angiography ; Female ; Humans ; Male ; Middle Aged ; Pilot Projects ; Singapore ; Tomography, X-Ray Computed ; Ultrasonography, Doppler, Transcranial

BACKGROUND AND AIMIntravenously-administered tissue plasminogen activator (IV-TPA) induces thrombolysis and remains the only FDA-approved therapy for acute ischaemic stroke. IV-TPA thrombolysis has been approved recently in Singapore for acute stroke. Continuous exposure of clot to 2-MHz pulsed-wave transcranial Doppler (TCD) ultrasound during IV-TPA infusion is known to augment thrombolysis. We aimed to determine the feasibility, safety and efficacy of ultrasound-assisted thrombolysis in acute ischaemic stroke in Singapore.

SUBJECTS AND METHODSConsecutive patients with acute ischaemic stroke due to intracranial arterial-occlusions were treated with standard IV-tPA and continuously monitored with 2-MHz TCD according to the CLOTBUST-trial protocol. Arterial recanalisation was determined with Thrombolysis in Brain Ischemia (TIBI) flow-grading system. Safety and efficacy of ultrasoundassisted thrombolysis were assessed by rates of symptomatic intracranial haemorrhage (sICH) and functional recovery at 1 month, respectively.

RESULTSFive consecutive patients (mean age 58 years, 3 men and 3 of Chinese ethnicity) were included. Mean time elapsed between symptom onset and presentation to emergency room was 98 minutes (range, 50 to 135 minutes) while the mean time interval between symptom onset to IV-TPA bolus was 144 minutes (range, 125 to 180 minutes). Partial or complete recanalisation with reduction in the stroke severity was noted in 4 out of the 5 patients during IV-TPA infusion (mean change in NIHSS = 4 points; range 2 to 8 points). None of our patients developed sICH while 4 patients demonstrated good functional outcome at 1 month.

CONCLUSIONSOur preliminary study demonstrates the feasibility, safety and efficacy of ultrasound-assisted thrombolysis in acute ischaemic stroke in Singapore. Continuous TCD-monitoring during IV-TPA infusion provides real-time information, enhances thrombolysis and improves functional outcomes in acute ischaemic stroke.

Aged ; Brain Infarction ; diagnostic imaging ; Female ; Fibrinolytic Agents ; administration & dosage ; Humans ; Infusions, Intravenous ; Male ; Middle Aged ; Thrombolytic Therapy ; methods ; Tissue Plasminogen Activator ; administration & dosage ; Ultrasonography, Interventional ; methods

Cerebrovascular Circulation ; drug effects ; Computer Systems ; Fibrinolytic Agents ; administration & dosage ; pharmacology ; Humans ; Infarction, Middle Cerebral Artery ; drug therapy ; physiopathology ; Infusions, Intravenous ; Male ; Middle Aged ; Regional Blood Flow ; drug effects ; Thrombolytic Therapy ; Tissue Plasminogen Activator ; administration & dosage ; pharmacology

No abstract available.
Aneurysm, False ; Carotid Artery Injuries*

Background: and Purpose Although onset-to-treatment time is associated with early clinical recovery in acute ischemic stroke (AIS) patients treated with intravenous tissue plasminogen activator (tPA), the effect of the timing of tPA-induced recanalization on functional outcomes remains debatable. Methods: We conducted a multicenter, prospective observational cohort study to determine whether early (within 1-hour from tPA-bolus) complete or partial recanalization assessed during 2-hour real-time transcranial Doppler monitoring is associated with improved outcomes in patients with proximal occlusions. Outcome events included dramatic clinical recovery (DCR) within 2 and 24-hours from tPA-bolus, 3-month mortality, favorable functional outcome (FFO) and functional independence (FI) defined as modified Rankin Scale (mRS) scores of 0–1 and 0–2 respectively. Results: We enrolled 480 AIS patients (mean age 66±15 years, 60% men, baseline National Institutes of Health Stroke Scale score 15). Patients with early recanalization (53%) had significantly (P<0.001) higher rates of DCR at 2-hour (54% vs. 10%) and 24-hour (63% vs. 22%), 3-month FFO (67% vs. 28%) and FI (81% vs. 39%). Three-month mortality rates (6% vs. 17%) and distribution of 3-month mRS scores were significantly lower in the early recanalization group. After adjusting for potential confounders, early recanalization was independently associated with higher odds of 3-month FFO (odds ratio [OR], 6.19; 95% confidence interval [CI], 3.88 to 9.88) and lower likelihood of 3-month mortality (OR, 0.34; 95% CI, 0.17 to 0.67). Onset to treatment time correlated to the elapsed time between tPA-bolus and recanalization (unstandardized linear regression coefficient, 0.13; 95% CI, 0.06 to 0.19). Conclusions Earlier tPA treatment after stroke onset is associated with faster tPA-induced recanalization. Earlier onset-to-recanalization time results in improved functional recovery and survival in AIS patients with proximal intracranial occlusions.

INTRODUCTION: Diabetes increases the risk of ischaemic stroke especially among Asians. This study aims to investigate contemporaneous long-term cardiovascular outcomes of ischaemic stroke patients with diabetes in a multi-ethnic Asian cohort. METHODS: Consecutive patients with ischaemic stroke were recruited from the National University Hospital, Singapore. Data on age, gender, ethnicity, risk factors (including diabetes status and body mass index [BMI]), stroke severity and mechanisms were collected. These patients were followed up until the day of the first cardiovascular event or July 2016, whichever was earlier. The primary endpoint was the time from enrolment to the first occurrence of a composite of cerebrovascular and coronary artery events. RESULTS: Between July 2011 and December 2013, 720 patients (mean age 60.6 years, 71% men, 43% with diabetes, median National Institute Health Stroke Severity scale 2) were enrolled and followed up. A total of 175 cardiovascular events occurred during a median follow-up of 3.25 years (6.90 events per 1,000 person-month), comprising 133 cerebrovascular and 42 coronary artery events. The adjusted hazard ratio of diabetes was 1.50 (95% CI 1.08-2.10). In a multivariable Cox proportional hazards model, Malay and Indian ethnicities, BMI <23kg/m2 and a prior diagnosis of diabetes were identified as independent predictors of recurrent cardiovascular events. CONCLUSION Our study provides quantitative data on the event rates of ischaemic stroke patients with diabetes. These findings provide insights on stroke predictors in a multi-ethnic Asian population, which may have implications in the design of future interventional studies.