Changes in Bihemispheric Structural Connectivity Following Middle Cerebral Artery Infarction

This study investigated the changes in the structural connectivity of the bilateral hemispheres over time following a middle cerebral artery infarction. Eighteen patients in the subacute group and nine patients in the chronic group with mild upper extremity motor impairment (Fugl-Meyer motor assessment score for the upper limb > 43) following middle cerebral artery infarction were retrospectively evaluated in this study. All the patients underwent T1-weighted and diffusion tensor imaging. Tract-based statistical analyses of fractional anisotropy were used to compare the changes in the bilateral structural connectivity with those of age-matched normal controls. The corticospinal tract pathway of the affected hemisphere, corpus callosum, and corona radiata of the unaffected hemisphere had decreased structural connectivity in the subacute group, while the motor association area and anterior corpus callosum in the bilateral frontal lobes had increased structural connectivity in the chronic group. The bilateral hemispheres were influenced even in patients with mild motor impairment following middle cerebral artery infarction, and the structural connectivity of the bilateral hemispheres changed according to the time following the stroke.

20-hydroxyeiscosatetraenoic acid may be as a predictor of malignant middle cerebral artery infarction in patients with massive middle cerebral artery infarction

Background Early identification of massive middle cerebral artery infarction (MCAI) at risk for malignant MCAI (m-MCAI) may be useful in selecting patients for aggressive therapies. The aim of this study was to determine whether CYP metabolites may help to predict impending m-MCAI. Methods This is a prospective, two-center observational study in 256 patients with acute massive MCAI. Plasma levels of 20-hydroxyeicosatetraenoic acid (20-HETE), epoxyeicosatrienoic acids, and dihydroxyeicosatrienoic acids were measured at admission. Brain computed tomography (CT) was performed at admission and repeated between day 3 and 7, or earlier if there was neurological deterioration. The primary outcome was m-MCAI. The m-MCAI was diagnosed when follow-up brain CT detected a more than two-thirds space-occupying MCAI with midline shift, compression of the basal cisterns, and neurological worsening. Results In total of 256 enrolled patients, 77 (30.1%) patients developed m-MCAI. Among the 77 patients with m-MCAI, 60 (77.9%) patients died during 3 months of stroke onset. 20-HETE level on admission was significantly higher in patients with m-MCAI than those without m-MCAI. There was an increase in the risk of m-MCAI with increase of 20-HETE levels. The third and fourth quartiles of 20-HETE levels were independent predictors of m-MCAI (OR: 2.86; 95% CI: 1.16 – 6.68; P = 0.025, and OR: 4.23; 95% CI: 1.35 – 8.26; P = 0.002, respectively). Conclusions Incidence of m-MCAI was high in patients with massive MCAI and the prognosis of m-MCAI is very poor. Elevated plasma 20-HETE may be as a predictor for m-MCAI in acute massive MCAI, and it might useful in clinical practice in therapeutic decision making.

Factors affecting outcome of decompressive hemicraniectomy in malignant middle cerebral artery infarction

Introduction: Decompressive Hemicraniectomy (DHC) is a standard surgical management of malignant MCA (MMCA) infarction. This study was conducted to review the outcome of surgery and to find out factors associated with favorable outcomes at a tertiary level neurosurgery referral centre. Methods and Materials: This is a retrospective study conducted over a period of three years from 2017 to 2019. Patient charts were reviewed for variable like age, sex, timing of surgery, GCS at presentation, length of ventilation, length of ICU admission and length of hospital stay. Primary outcome measure was GOSE: favorable (<=4) and unfavorable (>=5). SPSS version 23 was used for analysis. Results: A total of 28 patients underwent DHC out of which 21 patients were available for analysis. Mean age of patients was 58.62 years. Mean GCS on arrival was 11.86. Mean interval duration between event and surgery was 51.88 hours. Mean duration of ventilation was 4.43 days. Mean length of ICU stay was 5.95 days. Mean hospital stay was 22.33 days. Mean GOSE was 2. Mean age was significantly lower in patients with favorable GOSE. Early surgery had better mean GOSE which was not significant statistically. Conclusion: Patients with age less than 50 years have favorable GOSE despite MMCA infarction if decompressive hemicraniectomy is performed to accommodate brain swelling. Early surgery at presentation rather than waiting for deterioration might improve the outcome.

Hyperdense middle cerebral artery sign predicts favorable outcome after decompressive craniectomy in patients with malignant middle cerebral artery infarction

Background Malignant middle cerebral artery infarction (MMI) is a life-threatening cerebral vascular event. Early decompressive craniectomy (DC) has proven to be an effective treatment strategy. However, the ideal candidate for DC continues to be debated. Purpose To investigate whether a hyperdense middle cerebral artery sign (HMCAS) provides prognostic value after DC in patients with MMI. Material and Methods We reviewed clinical information and radiological parameters on computed tomography of 42 patients with MMI who underwent DC. Functional outcome was assessed according to the modified Rankin scale (mRS) at three months as follows: favorable outcome (mRS ≤ 4) versus unfavorable outcome (mRS > 4). Logistic regression analysis was used to identify predictors of functional outcome after DC in patients with MMI. Results Age (odds ratio [OR] = 0.87; 95% confidence interval [CI] = 0.78–0.97; P = 0.014) and HMCAS (OR = 7.40; 95% CI = 1.35–40.48; P = 0.021) were associated with functional outcome. The area under the receiver operating characteristic curve for predicting favorable outcome using the combination of age and HMCAS was 0.882, and the sensitivity and specificity were 0.947 and 0.696, respectively. Conclusion Patients with MMI with HMCAS, as well as younger patients, often showed a favorable outcome after DC in this study.

Hemispheric Difference of Regional Brain Function Exists in Patients With Acute Stroke in Different Cerebral Hemispheres: A Resting-State fMRI Study

ObjectiveTo explore the different compensatory mechanisms of brain function between the patients with brain dysfunction after acute ischemic stroke (AIS) in the dominant hemisphere and the non-dominant hemisphere based on Resting-state Functional Magnetic Resonance Imaging (Rs-fMRI).MethodsIn this trial, 15 healthy subjects (HS) were used as blank controls. In total, 30 hemiplegic patients with middle cerebral artery acute infarction of different dominant hemispheres were divided into the dominant hemisphere group (DH) and the non-dominant hemisphere group (NDH), scanned by a 3.0 T MRI scanner, to obtain the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) and compare the differences.ResultsCompared with the HS, increased ALFF values in the brain areas, such as the bilateral midbrain, were observed in DH. Meanwhile decreased ReHo values in the brain areas, such as the right postcentral gyrus (BA3), were also observed. Enhanced ALFF values in the brain areas, such as the left BA6, and enhanced ReHo values in the brain areas, such as the left precuneus, were observed in the NDH. The ALFF and ReHo values of the right BA9 and precentral gyrus were both increased. Compared with DH, the NDH group showed lower ALFF values in the left supplementary motor area and lower ReHo values in the right BA10.ConclusionAfter acute infarction in the middle cerebral artery of the dominant hemisphere, a compensation mechanism is triggered in brain areas of the ipsilateral cortex regulating motor-related pathways, while some brain areas related to cognition, sensation, and motor in the contralateral cortex are suppressed, and the connection with the peripheral brain regions is weakened. After acute infarction in the middle cerebral artery of the non-dominant hemisphere, compensatory activation appears in motor control-related brain areas of the dominant hemisphere. After acute middle cerebral artery infarction in the dominant hemisphere, compared with the non-dominant hemisphere, functional specificity in the bilateral supplementary motor area weakens. After acute middle cerebral artery infarction in different hemispheres, there are hemispheric differences in the compensatory mechanism of brain function.