Reliability of Hand-Held Transcranial Doppler with M-mode Ultrasound in Middle Cerebral Artery Measurement.

PURPOSE: To determine the intra- and interrater agreement of mean flow velocity (MFV) and pulsatility index (PI) measurement in middle cerebral arteries, assessed by transcranial Doppler (TCD) with M-mode. METHODS: Masked experienced neurosonologists performed TCD with M-mode using handheld probe in healthy adult volunteers. The Bland-Altman method for concordance and intraclass correlation coefficient were used. RESULTS: Seventy-seven healthy volunteers and seven raters participated (3 on regular TCD shift and 4 off-shift). The intrarater absolute mean difference between measurements was 5.5 cm/s [95% confidence interval (CI), 4.7-6.3] for MVF and 0.073 (95% CI, 0.063-0.083) for PI. The difference between MFV measurements was significantly higher in off-shift raters (p = 0.015). The interrater absolute mean difference between measurements was 6.5 cm/s (95% CI, 5.5-7.5) for MVF and 0.065 (95% CI, 0.059-0.071) for PI. No influence was found for the middle cerebral artery side, volunteer's sex, or age, and there was no significant difference between raters. The intraclass correlation coefficient was 82.2% (95% CI 77.8-85.6) and 72.9% (95% CI 67.4-77.6) for MFV and PI, respectively. CONCLUSIONS: There exists good intra- and interrater agreement in MFV and PI measurements using M-mode TCD. These results support the use of this noninvasive tool and are important for clinical and investigational purposes.

[Sonothrombolysis for acute ischemic stroke]. / Sonotrombolisis en el ataque cerebrovascular isquémico: once años de experiencia en Clínica Alemana de Santiago.

BACKGROUND: Sonothrombolysis (ST) is an emerging modality for the treatment of stroke. AIM: To assess the feasibility to perform ST in a Chilean hospital. MATERIAL AND METHODS: Patients attended at a private clinic with an acute ischemic stroke, between September 2002 and May 2013 and eligible for endovenous thrombolysis, were studied with a transcranial Doppler (Spencer PMD 100 or 150®). Those with an adequate sonographic window and a demonstrated arterial occlusion were monitored continuously with transcranial Doppler at the site of worst residual flow following the CLOTBUST study protocol. RESULTS: One thousand twenty six patients were studied, of whom 136 received intravenous thrombolysis (rt-PA) and 61, aged 66 ± 18 years (59% males), were subjected to ST (7% of total). Their median National Institutes of Health Stroke Scale score was 14, the lapse from symptom onset to rt-PA was 127 minutes (43-223). Middle cerebral artery (MCA) occlusion was found in 88.5% of patients. Complete recanalization was achieved in 44.3% of patients. Sixty percent had Modified Rankin Scale of 0 to 2 at 3 months (95% confidence intervals (CI) 48.1 to 72). Case fatality was 9.8% and asymptomatic intracranial hemorrhage occurred in 9.8% (95% CI: 4.3 to 20.2). CONCLUSIONS: ST can be carried out in a complex medical center and is safe.

Flat-head positioning increases cerebral blood flow in anterior circulation acute ischemic stroke. A cluster randomized phase IIb trial.

Background Whether lying-flat improves blood flow in patients with acute ischemic stroke is unknown. Our aim was to investigate if lying-flat "changes" cerebral blood flow velocities assessed by transcranial Doppler in acute ischemic stroke patients. Methods In a multicenter cluster clinical trial, we randomly assigned patients within 12 h from onset of a neurological deficit due to cerebral ischemia of the anterior circulation to lying-flat or upright head positioning. The primary outcome was a change of 8 cm/s or more in mean cerebral blood flow velocities on transcranial Doppler to the middle cerebral artery at 1 and 24 h post-randomization, adjusted for imbalance in baseline variables. Secondary outcomes included serious adverse events and physical functioning at 90 days. Results Ninety-four of 304 patients screened were recruited. The primary outcome occurred in 11 (26%) of 43 patients in the lying-flat group and in 6 (12%) of 51 in the upright group at 1 h (adjusted odds ratio, 3.81; 95% CI, 1.07 to 13.54), and in 23 (53%) and 18 (36%) patients in these respective groups at 24 h (adjusted odds ratio, 3.04; 95% CI, 1.08 to 8.53). There were no between-group differences in serious adverse events, including pneumonia, heart failure or mortality, nor in functional outcome at 3 months (adjusted common odds ratio, 1.38; 95% CI 0.64 to 3.00). Conclusion The lying-flat head position was associated with a significant increase in cerebral blood flow velocities at one and 24 h within the ipsilateral hemisphere of anterior circulation acute ischemic stroke, without serious safety concerns. Clinical trial registration-URL: http://www.clinicaltrials.gov . Unique identifier: NCT01706094.

Head position and cerebral blood flow in acute ischemic stroke patients: Protocol for the pilot phase, cluster randomized, Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot).

RATIONALE: Few proven interventions exist for acute ischemic stroke (AIS), and most are expensive and restricted in applicability. Lying flat 'head down' positioning of AIS patients has been shown to increase by as much as 20%, mean cerebral blood flow velocities (CBFV) measured by transcranial Doppler (TCD) but whether this translates into clinical improvement is uncertain. AIM: To determine if the lying flat position increases mean CBFV in the affected territory as compared to the sitting up position in AIS patients. METHODS AND DESIGN: Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot) is a cluster randomized (clusters being months), assessor-blinded end-point, phase IIb trial, where consecutive adults with anterior circulation AIS within 12 h of symptom onset are positioned to a randomized position for 48 h with TCD performed serially. STUDY OUTCOMES: Primary outcome is mean CBFV on TCD at 1 and 24 h after positioning. Secondary outcomes include: serious adverse events, neurological impairment at seven days, and death and disability at 90 days. SAMPLE SIZE ESTIMATES: Assuming an increase of 8.3 (SD 11.4) cm/s in average of mean CBFV when tilted from 30° to 0°, 46 clusters are required (92 patients in total) to detect a 20% increase of mean CBFV with 90% power and 5% level of significance. CONCLUSION: HeadPoST pilot is a cluster randomized multicenter clinical trial investigating the effect of head positioning on mean CBFV in anterior circulation AIS.

Sonotrombolisis en el ataque cerebrovascular isquémico: once años de experiencia en Clínica Alemana de Santiago / Sonothrombolysis for acute ischemic stroke

Background: Sonothrombolysis (ST) is an emerging modality for the treatment of stroke. Aim: To assess the feasibility to perform ST in a Chilean hospital. Material and Methods: Patients attended at a private clinic with an acute ischemic stroke, between September 2002 and May 2013 and eligible for endovenous thrombolysis, were studied with a transcranial Doppler (Spencer PMD 100 or 150®). Those with an adequate sonographic window and a demonstrated arterial occlusion were monitored continuously with transcranial Doppler at the site of worst residual flow following the CLOTBUST study protocol. Results: One thousand twenty six patients were studied, of whom 136 received intravenous thrombolysis (rt-PA) and 61, aged 66 ± 18 years (59% males), were subjected to ST (7% of total). Their median National Institutes of Health Stroke Scale score was 14, the lapse from symptom onset to rt-PA was 127 minutes (43-223). Middle cerebral artery (MCA) occlusion was found in 88.5% of patients. Complete recanalization was achieved in 44.3% of patients. Sixty percent had Modified Rankin Scale of 0 to 2 at 3 months (95% confidence intervals (CI) 48.1 to 72). Case fatality was 9.8% and asymptomatic intracranial hemorrhage occurred in 9.8% (95% CI: 4.3 to 20.2). Conclusions: ST can be carried out in a complex medical center and is safe.