There has been a significant increase in obesity rates worldwide with the corresponding surge in diabetes. Diabetes causes various microvascular and macrovascular changes often culminating in major clinical complications, 1 of which, is stroke. Although gains have been made over the last 2 decades in reducing the burden of stroke, the recent rise in rates of diabetes threatens to reverse these advances. Of the several mechanistic stroke subtypes, individuals with diabetes are especially susceptible to the consequences of cerebral small vessel diseases. Hyperglycemia confers greater risk of stroke occurrence. This increased risk is often seen in individuals with diabetes and is associated with poorer clinical outcomes (including higher mortality), especially following ischemic stroke. Improving stroke outcomes in individuals with diabetes requires prompt and persistent implementation of evidence-based medical therapies as well as adoption of beneficial lifestyle practices.

Background and Purpose Despite being the gold standard technique for stroke assessment, conventional diffusion magnetic resonance imaging (dMRI) provides only partial information about tissue microstructure. Diffusional kurtosis imaging (DKI) is an advanced dMRI method that yields, in addition to conventional diffusion information, the diffusional kurtosis (K), which may help improve characterization of tissue microstructure. In particular, this additional information permits the description of white matter (WM) in terms of WM-specific diffusion metrics (WMM). The goal of this study is to elucidate possible biophysical mechanisms underlying ischemia using these new WMM. Methods We performed a retrospective review of clinical and DKI data of forty-four acute/subacute ischemic stroke patients. Patients with a history of brain neoplasm or intracranial hemorrhages were excluded from this study. ROI analysis was performed to measure percent change of diffusion metrics in ischemic WM lesions compared to the contralateral hemisphere. Results K maps exhibit distinct ischemic lesion heterogeneity that is not apparent on apparent diffusion coefficient (ADC) maps. K metrics also have significantly higher absolute percent change than complementary conventional diffusion metrics. Our WMM reveal an increase in axonal density and a larger decrease in the intra-axonal (Da) compared to extra-axonal (De) diffusion microenvironment of the ischemic WM lesion. Conclusions The well-known decrease in the ADC of WM following ischemia is found to be mainly driven by a significant drop in Da. Our results suggest that ischemia preferentially alters intra-axonal environment, consistent with a proposed mechanism of focal enlargement of axons known as axonal swelling or beading.

Purpose of Review Despite current rehabilitative strategies, stroke remains a leading cause of disability in the USA. There is a window of enhanced neuroplasticity early after stroke, during which the brain’s dynamic response to injury is heightened and rehabilitation might be particularly effective. This review summarizes the evidence of the existence of this plastic window, and the evidence regarding safety and efficacy of early rehabilitative strategies for several stroke domain-specific deficits. Recent Findings Overall, trials of rehabilitation in the first 2 weeks after stroke are scarce. In the realm of very early mobilization, one large and one small trial found potential harm from mobilizing patients within the first 24 h after stroke, and only one small trial found benefit in doing so. For the upper extremity, constraint-induced movement therapy appears to have benefit when started within 2 weeks of stroke. Evidence for non-invasive brain stimulation in the acute period remains scant and inconclusive. For aphasia, the evidence is mixed, but intensive early therapy might be of benefit for patients with severe aphasia. Mirror therapy begun early after stroke shows promise for the alleviation of neglect. Novel approaches to treating dysphagia early after stroke appear promising, but the high rate of spontaneous improvement makes their benefit difficult to gauge. Summary The optimal time to begin rehabilitation after a stroke remains unsettled, though the evidence is mounting that for at least some deficits, initiation of rehabilitative strategies within the first 2 weeks of stroke is beneficial. Commencing intensive therapy in the first 24 h may be harmful.

Background and purpose Treatment options for stroke related dysphagia are currently limited. In this study we investigated whether non-invasive brain stimulation in combination with swallowing maneuvers facilitates swallowing recovery in dysphagic stroke patients during early stroke convalescence. Methods Fourteen patients with subacute unilateral hemispheric infarction were randomized to anodal transcranial direct current stimulation (tDCS) versus sham stimulation to the sensorimotor cortical representation of swallowing in the unaffected hemisphere over 5 consecutive days with concurrent standardized swallowing maneuvers. Severity of dysphagia was measured using a validated swallowing scale, Dysphagia Outcome and Severity Scale (DOSS), before the first and after the last session of tDCS or sham. The effect of tDCS was analyzed in a multivariate linear regression model using changes in DOSS as the outcome variable, after adjusting for the effects of other potential confounding variables such as the NIH Stroke Scale (NIHSS) and DOSS scores at baseline, acute ischemic lesion volumes, patient’s age and time from stroke onset to stimulation. Results Patients who received anodal tDCS gained 2.60 points improvement in DOSS scores compared to patients in the sham stimulation group who showed an improvement of 1.25 points (P=0.019) after controlling for the effects of other aforementioned variables. 6 out 7 (86%) patients in tDCS stimulation group gained at least 2 points improvement compared with 3 out 7 (43%) patients in sham group (P=0.107). Conclusion Since brainstem swallowing centers have bilateral cortical innervations, measures that enhance cortical input and sensorimotor control of brainstem swallowing may be beneficial for dysphagia recovery.