Effects of Diabetes on Motor Recovery after Cerebral Infarct: A Diffusion Tensor Imaging Study

Anti-motion Ultrafast T2 Mapping Technique for Quantitative Detection of the Normal-Appearing Corticospinal Tract Changes in Subacute-Chronic Stroke Patients with Distal Lesions

RATIONALE AND OBJECTIVES

Stroke patients commonly face challenges during magnetic resonance imaging (MRI) examinations due to involuntary movements. This study aims to overcome these challenges by utilizing multiple overlapping-echo detachment (MOLED) quantitative technology. Through this technology, we also seek to detect microstructural changes of the normal-appearing corticospinal tract (NA-CST) in subacute-chronic stroke patients.

MATERIALS AND METHODS

79 patients underwent 3.0 T MRI scans, including routine scans and MOLED technique. A deep learning network was utilized for image reconstruction, and the accuracy, reliability, and resistance to motion of the MOLED technique were validated on phantoms and volunteers. Subsequently, we assessed motor dysfunction severity, ischemic lesion volume, T2 values of the bilateral NA-CST, and the T2 ratio (rT2) between the ipsilesional and contralesional NA-CST in patients.

RESULTS

The MOLED technique showed high accuracy (P < 0.001) and excellent repeatability, with a mean coefficient of variation (CoV) of 1.11%. It provided reliable quantitative results even under head movement, with a mean difference (Meandiff)= 0.28% and a standard deviation difference (SDdiff)= 1.34%. Additionally, the T2 value of the ipsilesional NA-CST was significantly higher than contralesional side (P < 0.001), and a positive correlation was observed between rT2 and the severity of motor dysfunction (rs =0.575, P < 0.001). Furthermore, rT2 successfully predicted post-stroke motor impairment, with an area under the curve (AUC) was 0.883.

CONCLUSION

The MOLED technique offers significant advantages for quantitatively imaging stroke patients with involuntary movements. Additionally, T2 mapping from MOLED can detect microstructural changes in the NA-CST, potentially aiding in monitoring stroke-induced motor impairment.

Effects of atrial fibrillation on motor outcome in patients with cerebral infarction

BACKGROUND

Atrial fibrillation (AF) has been a leading cause of cerebral infarction, but the association with motor outcome after cerebral infarction remains unreported. In this study, we attempted to identify whether AF affects motor outcomes after cerebral infarction.

METHODS

Seventy-six patients with a first-incidence cerebral infarction and who completed 6 months of rehabilitation were recruited to this retrospective study. The patients were divided into two groups based on the presence of AF (AF and non-AF groups). The upper extremity motricity index, lower extremity motricity index (LMI), modified Brunnstrom classification, and functional ambulation category (FAC) were evaluated, and those results were obtained within the first day and after 6 months of onset. Clinical factors that could affect motor outcome after cerebral infarction were also obtained.

RESULTS

Compared with the non-AF group, the AF group had an upper extremity motricity index (47.15 ± 20.30 vs 58.66 ± 19.19; P = .032), LMI (53.42 ± 12.27 vs 65.58 ± 13.86; P = .001), and FAC scores (2.39 ± 0.93 vs 3.35 ± 0.93; P < .001) at 6 months after onset. Moreover, the AF group showed a lower FAC score gain than the non-AF group at 6 months after onset (2.33 ± 0.95 vs 3.28 ± 0.94; P < .001). Multivariate linear regression analyses showed that presence of AF had negative correlation with LMI gain (β = -0.197; P = .010) and FAC gain (β = -0.254; P = .011).

CONCLUSION

We observed that AF had a negative effect on the motor outcome of the affected leg and the recovery of gait function in patients with cerebral infarction.

Effect of Diabetes on Post-stroke Recovery: A Systematic Narrative Review

Background: Patients with stroke often have comorbid diabetes. Considering its detrimental effects on brain function, diabetes may increase the risk of poor recovery.

Methods: The aim of this review was to investigate the effect of diabetes on post-stroke recovery by a systematic review. Several specific aspects of post-stroke recovery, including activities of daily living (ADL), motor, cognitive, and quality of life (QOL) recovery, were examined. We searched the PubMed, SCOPUS, Embase, and Cochrane Library databases for relevant studies on the effect of diabetes on post-stroke recovery, published until May 26, 2021. A total of 52,051 potentially relevant articles were identified. After reading the titles and abstracts and assessing their eligibility based on full-text articles, 34 publications were included in this review.

Results: Of 29 studies that assessed ADL recovery after stroke, 22 studies suggested that diabetes had a negative effect on recovery of ADL after stroke. Regarding motor recovery, only one out of four studies showed that diabetes had some effect on motor recovery after stroke. Of the two studies on cognitive recovery, one reported that diabetes was an independent predictor of poor cognitive recovery after stroke. Three studies on QOL reported that a poor QOL after stroke was associated with the presence of diabetes.

Conclusions: The current review suggests that the post-stroke recovery of ADL seems to be poorer in patients with diabetes than patients without diabetes. Further, there are insufficient data to conclude the effect of diabetes on motor and cognitive recovery, but it may have some influence on the quality of life after stroke.

Systematic Review Registration: doi: 10.37766/inplasy2021.11.0032, identifier: INPLASY2021110032.

Hematoma Evacuation via Image-Guided Para-Corticospinal Tract Approach in Patients with Spontaneous Intracerebral Hemorrhage

Introduction

Corticospinal tract injury caused by direct hematoma compression and secondary damage induced from blood toxic substances might influence the outcomes in patients with intracerebral hemorrhage (ICH). This study aimed to evaluate the safety and efficacy of hematoma evacuation via image-guided para-corticospinal tract approach based on the protection of compressed or residual corticospinal tract.

Methods

Seventy-five patients with ICH who underwent the image-guided para-corticospinal tract approach were retrospectively collected into the surgery group. Diffusion tensor imaging or computed tomography angiography was performed to identify the relationship between important white matter tracts and hematoma. The neuronavigation system for the preoperative imaging data loaded was used to identify the location of the burr hole, insertion trajectory, and depth of insertion. Cortical entry points and insertion trajectories were kept parallel to the corticospinal tract route into the hematoma based on the protection of compressed or residual corticospinal tract. Hematoma was removed under the image-guided para-corticospinal tract approach. Seventy-five age-, sex-, hematoma site-, and volume-matched patients with ICH who underwent conservative treatment were selected as controls. Demographical, clinical, radiological, and treatment-related data were retrospectively analyzed. Functional outcome was evaluated by modified Rankin scale on day 90.

Results

A total of 150 patients with ICH were retrospectively enrolled. The median Glasgow coma scale (GCS) score on admission was 11 (IQR 8–13). Deep hematoma (thalamus and basal ganglion) was present in 86.7% (130 patients). The mean hematoma volume on admission was 47 ± 19 mL, and the postoperative hematoma volume was 11 ± 10 mL. A higher proportion of favorable outcome was observed in the surgery group than in conservative treatment group (32.0% versus 17.4%; p = 0.037).

Conclusion

Hematoma evacuation via image-guided para-corticospinal tract approach based on the protection of compressed or residual corticospinal tract seems to be safer in patients with ICH with a relatively higher functional independence.

Does injury of the thalamocortical connection between the mediodorsal nucleus of the thalamus and the dorsolateral prefrontal cortex affect motor recovery after cerebral infarct?

We assessed the state of the thalamocortical connection between the mediodorsal nucleus (MD) and the dorsolateral prefrontal cortex (DLPFC) in patients with corona radiata infarct using diffusion tensor tractography (DTT). Altogether, 110 patients with corona radiata infarct were recruited, all of whom underwent DTT at an early stage following infarct onset. Based on the integrity of CST (CST+: CST was preserved around the infarct, CST-: CST was interrupted by the infarct) and the integrity of thalamocortical connection between the MD of thalamus and the DLPFC (DLPFC+: the connection was preserved, DLPFC-: the connection was interrupted), patients were divided into 4 groups: CST+/DLPFC+ (37 patients), CST+/DLPFC- (21 patients), CST-/DLPFC+ (25 patients), and CST-/DLPFC- (27 patients) groups. Motor function was evaluated using the upper Motricity Index (MI), lower MI, modified Brunnstrom classification, and the functional ambulation category at baseline and at 6 months post-onset. In patients with preserved CST integrity, the status of the thalamocortical connection had no impact on the assessed motor outcomes at 6 months post-stroke. However, in patients with disrupted CST integrity, those with preserved thalamocortical connection integrity had significantly higher motor function scores in all assessed outcomes 6 months post-stroke than those with disrupted thalamocortical connection integrity. The preservation or disruption of the thalamocortical connection between the MD of the thalamus and the DLPFC is an important factor for motor function recovery when CST integrity is also disrupted.

Diabetes, stroke, and neuroresilience: looking beyond hyperglycemia

Ischemic stroke is a leading cause of morbidity and mortality among type 2 diabetic patients. Preclinical and translational studies have identified critical pathophysiological mediators of stroke risk, recurrence, and poor outcome in diabetic patients, including endothelial dysfunction and inflammation. Most clinical trials of diabetes and stroke have focused on treating hyperglycemia alone. Pioglitazone has shown promise in secondary stroke prevention for insulin-resistant patients; however, its use is not yet widespread. Additional research into clinical therapies directed at diabetic pathophysiological processes to prevent stroke and improve outcome for diabetic stroke survivors is necessary. Resilience is the process of active adaptation to a stressor. In patients with diabetes, stroke recovery is impaired by insulin resistance, endothelial dysfunction, and inflammation, which impair key neuroresilience pathways maintaining cerebrovascular integrity, resolving poststroke inflammation, stimulating neural plasticity, and preventing neurodegeneration. Our review summarizes the underpinnings of stroke risk in diabetes, the clinical consequences of stroke in diabetic patients, and proposes hypotheses and new avenues of research for therapeutics to stimulate neuroresilience pathways and improve stroke outcome in diabetic patients.

Improvement of Gait Dysfunction after Applying a Hinged Ankle-Foot Orthosis in a Hemiplegic Cerebral Palsy Patient with Disrupted Medial Lemniscus: A Case Report

We describe the successful application of hinged ankle−foot orthoses (AFOs) in a cerebral palsied (CP) patient with gait instability due to a disrupted medial lemniscus (ML). The patient was a 27-month-old male CP child with gait instability who presented with reduced knee flexion and ankle dorsiflexion, with severe genu recurvatum on his right lower extremity during gait. The patient had no motor weakness or spasticity. Conventional magnetic resonance imaging (MRI) revealed no definite abnormal lesion. However, diffusion tensor tractography (DTT) showed disruption of the left ML, consistent with right hemiplegic symptoms. The integrity of the major motor-related neural tracts, including the corticospinal and corticoreticulospinal tracts, was preserved. We considered that the patient’s abnormal gait pattern was related to the disrupted ML state. We applied hinged AFOs, which immediately resulted in a significantly stabilized gait. The angles of knee flexion and ankle dorsiflexion increased. Our findings indicate that the application of hinged AFOs could be a useful therapeutic option for CP patients with gait instability related to ML disruption. In addition, we showed that DTT is a useful tool for identifying the causative brain pathology in CP patients, especially when conventional brain MRIs show no specific lesion.

Prediction of muscle loss after stroke by analysis of corticospinal tract

Introduction

Skeletal muscle loss induces a poor rehabilitation outcome after stroke. Little is known about the usefulness of diffusion tensor tractography (DTT) findings of the corticospinal tract (CST) in terms of predicting muscle loss in affected limbs after stroke.

Methods

This research was designed as a preliminary study. Forty-four patients, with stroke onset more than one year earlier, were recruited. DTT was performed within 7–30 days after stroke onset. The patients were classified into two groups based on the DTT findings: a DTT+ group, in which the CST was preserved, and a DTT− group, in which the CST was interrupted by the stroke lesion. Additionally, the patients’ functions were evaluated based on the modified Brunnstrom classification and functional ambulation category.

Results

In the DTT− group, the values of the lean tissue mass of the affected upper and lower limbs were smaller than those of the unaffected side. On the other hand, in the DTT+ group, the values of the lean tissue mass between the affected and unaffected limbs were not significantly different.

Conclusion

The DTT evaluation of CST at the early stage of stroke may be useful for predicting muscle loss of the affected limb at the chronic stage in stroke patients.

Diabetes does not affect motor recovery after intracerebral hemorrhage

Background

This retrospective study evaluated whether diabetes affects motor outcome after stroke by analyzing the effects of diabetes on motor prognosis by controlling for critical factors, including lesion type and location, corticospinal tract (CST) state, patient age, lesion volume, and treatment method during the stroke.

Methodology

We recruited 221 patients with intracerebral hemorrhage (ICH) of the basal ganglia. We used diffusion tensor tractography to investigate the CST state. We also evaluated the hemorrhage volume. We obtained information on the presence of diabetes and age by chart review. Motor outcomes at 6 months were measured using the upper and lower limb motricity index (MI), modified Brunnstrom classification (MBC), and functional ambulation category (FAC). We used multiple linear regression tests to investigate whether diabetes affected motor outcomes after stroke after adjusting for other factors, including CST state, age, lesion volume, and treatment method.

Results

The presence of diabetes was not correlated with motor outcome measurements, including upper and lower MIs, MBC, and FAC, at 6 months after the onset. However, the CST state, age, lesion volume, and treatment method were significantly correlated with nearly all motor outcomes.

Conclusions

We found that diabetes did not significantly affect motor outcomes after ICH.

Injury of Corticospinal tract and Corticoreticular pathway caused by high-voltage electrical shock: a case report

Background

We imaged the corticospinal tract (CST) and corticoreticular pathway (CRP) using diffusion tensor tractography (DTT) to evaluate the cause of muscle weakness in a patient who was exposed to high-voltage electricity.

Case presentation

A 39-year-old man presented with quadriparesis after high-voltage electrical shock from power lines while working about 5.8 years ago. The electrical current entered through the left hand and exited through the occipital area of the head. The degree of weakness on bilateral upper and lower extremities was 3–4 on the Medical Research Council strength scale. Diffusion tensor imaging (DTI) was performed 5.8 years after onset. The CST and CRP were depicted by placing two regions of interest for each neural tract on the two-dimensional fractional anisotropy color map. DTT of the DTI scan showed that the bilateral CST and CRP were thinned compared to those of the healthy control subject. On the nerve conduction test, abnormal findings suggesting peripheral nerve lesion were not observed. Therefore, injury of bilateral CST and CRP seems to have contributed to our patient’s weakness after the electrical shock.

Conclusion

Depiction of neural tracts in the brain using DTT can assist in the accurate and detailed evaluation of the cause of neural deficit after electrical injury.