The impact of transcranial direct current stimulation on cerebral vasospasm in a rat model of subarachnoid hemorrhage

Systematic review and meta-analysis of transcranial direct current stimulation (tDCS) for global cognition in mild cognitive impairment and Alzheimer's disease

OBJECTIVE

To systematically assess the effectiveness of transcranial direct current stimulation (tDCS) on global cognition in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD).

DATA SOURCES

Ten databases were retrieved for pertinent Chinese and English studies published up until February 2023.

DATA EXTRACTION

Two researchers independently selected the literature, extracted the data, evaluated using the Cochrane Collaboration's quality criteria, and then cross-checked. Meta-analysis was performed using RevMan 5.4.

RESULTS

22 studies involving 1074 patients were included. Compared with the control group received the interventions such as pharmacotherapy, cognitive stimulation, et al., with/without sham-tDCS, while the experiment group received tDCS added to the interventions of the control group. The meta-analysis found that tDCS increased MMSE, MoCA, MODA scores and reduced the P300 latency scores (all P < 0.05).

CONCLUSION

The tDCS can ameliorate the global cognition of patients with MCI and AD, and it has a better rehabilitation effect than non-tDCS or sham-tDCS.

Three Pillars of Recovery After Aneurysmal Subarachnoid Hemorrhage: A Narrative Review

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating neurologic disease with high mortality and disability. There have been global improvements in survival, which has contributed to the prevalence of patients living with long-term sequelae related to this disease. The focus of active research has traditionally centered on acute treatment to reduce mortality, but now there is a great need to study the course of short- and long-term recovery in these patients. In this narrative review, we aim to describe the core pillars in the preservation of cerebral function, prevention of complications, the recent literature studying neuroplasticity, and future directions for research to enhance recovery outcomes following aSAH.

Neurocognitive Sequelae and Rehabilitation after Subarachnoid Hemorrhage: Optimizing Outcomes

Subarachnoid hemorrhage (SAH) is a medical emergency that requires immediate intervention. The etiology varies between cases; however, rupture of an intracranial aneurysm accounts for 80% of medical emergencies. Early intervention and treatment are essential to prevent long-term complications. Over the years, treatment of SAH has drastically improved, which is responsible for the rapid rise in SAH survivors. Post-SAH, a significant number of patients exhibit impairments in memory and executive function and report high rates of depression and anxiety that ultimately affect daily living, return to work, and quality of life. Given the rise in SAH survivors, rehabilitation post-SAH to optimize patient outcomes becomes crucial. The review addresses the current rehabilitative strategies to combat the neurocognitive and behavioral issues that may arise following SAH.

Cervical spinal cord stimulation for prevention and treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage: clinical and radiographic outcomes of a prospective single-center clinical pilot study

BACKGROUND

Cerebral vasospasm induced by aneurysmal subarachnoid hemorrhage (aSAH) is a major cause of high morbidity and mortality, for which there is no consistently effective treatment. Cervical spinal cord stimulation (cSCS) has been shown to induce vasodilatation and improve peripheral and cerebral blood flow in both animal and human studies. This pilot study was performed to assess the clinical effect and long-term results of cSCS treatment in aSAH patients.

METHODS

This was the first IRB- and US FDA-approved prospective non-randomized non-controlled study comprising of 12 aSAH patients (8 women, 4 men, age range 34-62 years) treated between May and November 2008. All patients underwent up to 2 weeks of cSCS with a single percutaneously implanted 8-contact electrode. Neurological outcomes at discharge and follow-up of up to 13 years and mortality/complications rates were analyzed.

RESULTS

All 12 aSAH patients underwent cSCS electrode implantation immediately after securing the aneurysm. Patients were stimulated for 10-14 consecutive days starting within 3 days of aneurysm rupture. Angiographic vasospasm occurred in six patients; two patients developed new vasospasm-related neurological symptoms; both recovered completely by discharge time. One patient died from unrelated multi-system failure; the rest were followed up clinically (average, 7.5 years; range, 12-151 months) and angiographically (average, 6.5 years; range, 36-125 months). No delayed ischemic neurological deficits/strokes and no cSCS-related adverse effects were observed.

CONCLUSIONS

Our short- and long-term data suggest that cSCS is feasible and safe for patients in the acute aSAH settings. Small size of the patient cohort and lack of control do not allow us to conclude whether cSCS is able to prevent cerebral vasospasm, decrease its severity, and improve clinical outcomes in aSAH patients. However, our findings support further clinical trials and development of cSCS as a new concept to prevent and treat cerebral vasospasm.

TRIAL REGISTRATION

CLINICALTRIALS

gov NCT00766844, posted on 10/06/2008.

The Updated Role of Transcranial Ultrasound Neuromodulation in Ischemic Stroke: From Clinical and Basic Research

Ischemic stroke is a common cause of death and disability worldwide, which leads to serious neurological and physical dysfunction and results in heavy economic and social burdens. For now, timely and effective dissolution of thrombus, and ultimately improvement in the recovery of neurological functions, is the treatment strategy focus. Recently, many studies have reported that transcranial ultrasound stimulation (TUS), as a non-invasive method, can dissolve thrombus, improve cerebral blood circulation, and exert a neuroprotective effect post-stroke. TUS can promote functional recovery and improve rehabilitation efficacy among patients with ischemic stroke. This mini-review summarizes the potential mechanism and limitation of TUS in stroke aims to provide a new strategy for the future treatment of patients with ischemic stroke.

The Potential Role of Neuromodulation in Subarachnoid Hemorrhage

OBJECTIVES

Aneurysmal subarachnoid hemorrhage (SAH) continues to be a difficult cerebrovascular disease with limited pharmacologic treatment options. Cerebral vasospasm (CV) and delayed cerebral ischemia (DCI) are leading causes of morbidity and mortality after SAH. Despite the advances in the understanding of its pathophysiology and tremendous efforts to date, nimodipine is currently the sole Food and Drug Administration-approved treatment for patients with SAH, with benefits that are marginal at best. The neuromodulation therapies are promising, especially those that target CV and DCI to improve functional outcomes. The aim of this review is therefore to summarize the available evidence for each type of neuromodulation for CV and DCI, with a special focus on its pathophysiological mechanisms, in addition to their clinical utility and drawbacks, which we hope will lead to future translational therapy options after SAH.

MATERIALS AND METHODS

We conducted a comprehensive review of preclinical and clinical studies demonstrating the use of neuromodulation for SAH. The literature search was performed using PubMed, Embase, and ClinicalTrials.gov. A total of 21 articles published from 1992 to 2021 and eight clinical trials were chosen.

RESULTS

The studies reviewed provide a compelling demonstration that neuromodulation is a potentially useful strategy to target multiple mechanisms of DCI and thus to potentially improve functional outcomes from SAH. There are several types of neuromodulation that have been tested to treat CV and DCI, including the trigeminal/vagus/facial nerve stimulation, sphenopalatine ganglion and spinal cord stimulation, transcranial direct electrical stimulation, transcutaneous electrical neurostimulation, and electroacupuncture. Most of them are in the preclinical or early phases of clinical application; however, they show promising results.

CONCLUSIONS

DCI has a complex pathogenesis, making the unique anatomical distribution and pleiotropic capabilities of various types of neuromodulation a promising field of study. We may be at the cusp of a breakthrough in the use of these techniques for the treatment of this stubbornly difficult disease.