Use of decrease in apparent diffusion coefficient values to predict infarct age

Low intensity focused ultrasound stimulation in stroke: A phase I safety & feasibility trial

OBJECTIVE

We aimed to determine the maximum safe spatial-peak pulse-average intensity (ISPPA) of low-intensity focused ultrasound stimulation (LIFUS) in stroke patients and explore its effect on motor learning and corticospinal excitability.

METHODS

We adopted the classic 3 + 3 design to escalate ISPPA (estimated in-vivo transcranial value) from 0, 1, 2, 4, 6, to 8 W/cm2. Stopping rules were pre-defined: 2nd-degree scalp burn, clinical seizure, new lesion on diffusion-weighted imaging or major reduction in apparent diffusion coefficient, and participant discontinuation due to any reason. We applied 12-min LIFUS over the ipsilesional motor cortex while participants were concurrently practicing 3 blocks of a motor sequence learning (MSL) task using the affected hand. We measured MSL (response time) and corticospinal excitability (motor evoked potential) pre- and post-stimulation and compared MSL and corticospinal excitability between the LOW (0, 1, and 2 W/cm2) and HIGH (4, 6, and 8 W/cm2) groups.

RESULTS

ISPPA was escalated to 8 W/cm2 with 18 stroke participants without meeting the stopping rules. Compared to the LOW, more participants in the HIGH performed better on MSL (6/9 vs. 0/9, p = 0.009) and showed a sign of greater corticospinal excitability (7/9 vs. 5/9, p = 0.62).

INTERPRETATION

Our phase-I safety study suggests that one session of LIFUS up to 8 W/cm2 ISPPA is safe and feasible in stroke patients, and LIFUS at high intensity induces positive changes in both MSL and corticospinal excitability. The next logical step is to conduct a phase-II trial testing the efficacy of LIFUS and continuously monitoring its safety profiles.

Navigating the clinical landscape of artery of Percheron infarction: A systematic review

Introduction

Infarction of the artery of Percheron (AOP) is a rare vascular condition where a single arterial branch supplies blood to the thalamic and midbrain regions, leading to neurological deficits. The challenge lies in its often-delayed diagnosis due to its rarity and diverse clinical presentations, necessitating heightened awareness among clinicians for expedited diagnosis and appropriate therapeutic interventions.

Materials and methods

All relevant studies involving patients diagnosed with infarction of AOP were retrieved from PubMed, Google Scholar, Web of Science, and Scopus. Only human studies that were published in full English-language reports were included. Included in the search were the terms "Artery of Percheron," "infarction," "stroke," and "demarcation". Age, gender, presenting symptoms, treatment, recovery time, and outcome of patients with AOP infarction were all recorded.

Results

A systematic review was conducted on a total of 530 articles, out of which 130 articles met the specified requirements. The average age is 59, with men comprising 57.7% of the population. The symptoms reported were visual disturbance in 43.9% of cases and changed mental state in 77.2% of cases. Treatment options include conservative management (85.4%), thrombolysis (11.3%), and other approaches. The optimal age range for recovery is between 41 and 50 years old.

Conclusion

Our study on acute AOP infarction highlights male predominance, common comorbidities like hypertension and diabetes, and prevalent symptoms including visual disturbance and altered mental state. Early recognition is crucial, with thrombolytic therapy within the critical time window showing promising outcomes. These findings offer insights for enhanced clinical management of AOP infarction.

Assessment of Percheron infarction in images and clinical findings

OBJECTIVE

To assess the imaging and clinical features of patients with an artery of Percheron infarction comprehensively.

METHODS

Of 6539 patients with a first-ever stroke, 18 patients with a Percheron infarction were enrolled, and their images and clinical data were retrospectively investigated.

RESULTS

All patients underwent neurological intensive care unit (NICU) management. The initial symptom of a Percheron infarction included dizziness, transient blurred vision, double vision, barylalia, cerebellar ataxia, drowsiness, and a coma. Subsequent symptoms differed for the three subtypes of Percheron infarction, and the three subtypes are bilateral paramedian thalamic infarction with midbrain involvement, bilateral paramedian thalamic infarction without midbrain involvement, and bilateral paramedian and anterior thalamic infarction without midbrain involvement. Between favorable and unfavorable outcomes, there was no significant difference in the following patient characteristics including current smoking, hypertension, diabetes, hyperlipidemia, hyperhomocysteinemia, heart disease, time from stroke onset to medical care, and Glasgow Coma Scale score at admission (P>0.05), but there were significant differences in both the National Institute of Health stroke scale (NIHSS) and Acute Physiology and Chronic Health Evaluation II (APACHE II) score at admission (P<0.05). If the midbrain or larger infarct volume was involved or hemorrhagic transformation occurred, outcomes of a Percheron infarction were frequently unfavorable.

CONCLUSION

The clinical presentation of patients with a Percheron infarction is variable; early recognition, image performance, NICU management, NIHSS, and APACHE II score would help in diagnosis, evaluation, and treatment.