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AIM To explore the association between haemorrhagic transformation (HT) subtypes and functional outcome in acute ischaemic stroke (AIS) patients with successful recanalization treated by endovascular thrombectomy (EVT). MATERIALS and METHODS Consecutive patients with AIS due to large-vessel occlusion in the anterior circulation, who were treated between January 2015 and June 2019 and achieved successful EVT, were enrolled in this retrospective study. HT was categorized according to the Heidelberg Bleeding Classification. Functional outcome was evaluated using the 90-day modified Rankin Scale (mRS) after stroke onset. Ordinal logistic regression analysis was performed to determine the association of HT subtypes with functional outcomes. RESULTS A total of 243 patients were included for further analysis. Among them, 121 (49.8%) had HT. Ten (4.1%) patients were classified as haemorrhagic infarction (HI) subtype 1, 61 (25.1%) as HI subtype 2, 17 (7.0%) as parenchymal haematoma (PH) subtype 1, and 33 (13.6%) as PH subtype 2. Ordinal logistic regression analysis suggested that HI subtype 2 (adjusted common OR 0.357, 95% CI: 0.192–0.667), PH1 (adjusted common OR 0.254, 95% CI: 0.093–0.696) and PH subtype 2 (adjusted common OR 0.017, 95% CI: 0.006–0.051) were significantly associated with poor functional outcomes. CONCLUSION The present study shows that HI subtype 2, PH subtype 1, and PH subtype 2 are independently associated with poor clinical outcomes in AIS patients with successful recanalization after EVT.

Patients with comitant exotropia (CE) would usually develop compromised binocular vision and impaired stereoscopic depth perception, which could result in a profound decrease in quality of life. Although the deviated optic axis could be corrected surgically, the impaired stereovision and sensory eye balance may sometimes remain remnant. This study was to investigate the brain functional alterations in patients with CE before and after surgery, using resting-state functional magnetic resonance imaging (fMRI) with amplitude of low-frequency fluctuation (ALFF). Thirty-five patients with CE were recruited to undergo a preoperative fMRI scan, as well as 24 healthy controls (HCs). Twenty-four of the patients were available for rescanned fMRI one month after surgery. The ALFF method was used to evaluate the group differences of spontaneous brain activity. The correlations between ALFF values and clinical variables were analyzed in the patient group. Preoperatively, compared with HCs, 35 patients with CE showed significantly decreased ALFF values in one cluster involving bilateral calcarine sulcus, lingual gyrus and cuneus. The ALFF values in the above cluster were negatively correlated with disease duration (r = -0.379, P = 0.033). One month after surgery, 24 patients with available rescanned fMRI demonstrated increased ALFF values in one cluster located in bilateral cuneus, calcarine sulcus and lingual gyrus relative to the preoperative collection, while still reduced ALFF values in the cluster involving left calcarine sulcus and lingual gyrus compared with HCs. Our study revealed the functional changes of patients with CE in visual-associated brain areas before and after surgery. The findings may provide a new perspective for understanding the underlying pathological mechanisms of CE.

Our objective was to assess the impact of hs-cTnT elevation on functional outcome and mortality in AIS patients with large vessel occlusion (LVO) in the anterior circulation 3 months after ET and explore factors affecting hs-cTnT elevation. A total of 143 consecutive AIS patients with large vessel occlusion (LVO) in the anterior circulation following ET in a single stroke center were enrolled between January 2015 and November 2017. Hs-cTnT was quantitated on admission. Demographic characteristics, clinical data, functional outcome and all-cause mortality were compared between patients with elevated hs-cTnT levels (14 ng/L) and those with normal hs-cTnT levels (≤14 ng/L). 58/143(40.6%) patients showed elevated hs-cTnT levels before ET. Factors independently associated with hs-cTnT elevation were admission NIHSS score (OR = 1.08, 95% CI 1.01-1.16, p = 0.032), coronary heart disease (OR = 4.89, 95% CI 1.82-13.11, p = 0.002) and congestive heart failure (OR = 4.10, 95% CI 1.07-15.68, p = 0.039). In the univariate analysis, patients with elevated hs-cTnT levels were at significantly higher risk of 3-month poor outcome (p = 0.029) and mortality (p 0.001) than those with normal hs-cTnT levels. After multivariable analysis, hs-cTnT elevation remained an independent predictor of 3-month mortality (OR = 4.49, 95% CI 1.68-11.98, p = 0.003). In this cohort of AIS patients with LVO in the anterior circulation undergoing ET, hs-cTnT elevation is an independent predictor of 3-month mortality. Admission NIHSS score, coronary heart disease and congestive heart failure are independently associated with elevated hs-cTnT levels.

To investigate the feasibility of using magnetization transfer (MT) magnetic resonance imaging for evaluating patients with thyroid-associated ophthalmopathy (TAO), and determine its added value for differentiating active from inactive TAO and predicting clinical activity score (CAS), compared with conventional fat-saturated T2-weighted and diffusion-weighted imaging.Orbital MT, fat-saturated T2-weighted, and diffusion-weighted imaging of 60 prospectively enrolled consecutive patients with TAO was analyzed. Simplified histogram parameters (mean, max, min) of magnetization transfer ratio (MTR), signal intensity ratio (SIR), and apparent diffusion coefficient (ADC) at extraocular muscles were calculated for each orbit and compared between the active and inactive groups.Intraclass correlation coefficients of MTRs and SIRs were similar (0.802-0.963 vs 0.812-0.974, respectively), followed by those of ADCs (0.714-0.855). Patients with active TAO showed significantly lower MTRs and higher SIRs and ADCs than those with inactive TAO (P 0.05). MTRMT imaging could potentially be used as a noninvasive method for differentiating the activity of TAO and predicting CAS, thereby offering added value to conventional SIR and ADC.

AIM To evaluate the performance of T2 mapping histograms at the extraocular muscles (EOMs) in predicting the response to glucocorticoid therapy in the patients with active and moderate–severe thyroid-associated ophthalmopathy (TAO). MATERIALS AND METHODS Thirty active and moderate–severe TAO patients (responsive group, n=20; unresponsive group, n=10) were enrolled, and evaluated using T2 mapping before treatment. Histogram parameters (mean, median, max, min, 10th, 90th percentiles, skewness, and kurtosis) of T2 relaxation time (T2RT) at the EOMs for each orbit, and clinical variables (age, sex, disease duration, anti-thyroid treatment, smoking habit, pre-treatment thyroid function, thyrotrophin receptor antibody, diplopia presence, activity and severity scores) were collected and compared between groups. Logistic regression and receiver operating characteristic (ROC) curve analyses were used to assess the predictive value of identified independent variables for treatment response. RESULTS The responsive group showed significantly shorter disease duration (p=0.003), while higher T2RTmin than unresponsive group (p CONCLUSIONS Histogram analysis can help to exhibit the heterogeneity of T2RT at the EOMs. T2RTmin, together with disease duration may be the promising marker for predicting response to glucocorticoid therapy in the patients with active and moderate–severe TAO.

Objective To quantitatively evaluate nerve roots by measuring fractional anisotropy (FA) values in healthy volunteers and sciatica patients, visualize nerve roots by tractography, and compare the diagnostic efficacy between conventional magnetic resonance imaging (MRI) and DTI. Materials and methods Seventy-five sciatica patients and thirty-six healthy volunteers underwent MR imaging using DTI. FA values for L5–S1 lumbar nerve roots were calculated at three levels from DTI images. Tractography was performed on L3–S1 nerve roots. ROC analysis was performed for FA values. Results The lumbar nerve roots were visualized and FA values were calculated in all subjects. FA values decreased in compressed nerve roots and declined from proximal to distal along the compressed nerve tracts. Mean FA values were more sensitive and specific than MR imaging for differentiating compressed nerve roots, especially in the far lateral zone at distal nerves. Conclusions DTI can quantitatively evaluate compressed nerve roots, and DTT enables visualization of abnormal nerve tracts, providing vivid anatomic information and localization of probable nerve compression. DTI has great potential utility for evaluating lumbar nerve compression in sciatica.

Stroke is one of the leading causes of death worldwide and the main reason for long-term disability. An appropriate animal model of stroke is urgently required for understanding the exact pathophysiological mechanism of stroke and testing any new therapeutic regimen. Our work aimed to establish a canine stroke model occluding the middle cerebral artery (MCA) and blocking the ipsilateral internal carotid artery (ICA), and to assess the infarct lesions by magnetic resonance imaging. The stroke model was generated by injecting two autologous clots into each MCA, followed by 2-h ipsilateral ICA blockade (ilICAB) using a catheter in 15 healthy adult beagles. Outcome measurements included 24-h and 7-day postocclusion T2-weighted imaging (T2WI)-based infarct volume calculation. In addition, pial collateral score, canine neurobehavioral score and histopathologic results were documented. Out of 15 dogs, 12 with successful MCA occlusion (MCAO) and ilICAB survived 7 days without complications or casualties and MCA were reperfused at 7 days after occlusion. High signal intensity in the basal ganglia and cerebral cortex on T2WI was initially observed in each dog at 6 h after the procedure. The mean percentage hemispherical infarct volume corrected for edema in all dogs on T2WI at 24 h after occlusion was 12.99±1.57%, and the degree of variability was 12.08%. The infarct volumes at 24 h after occlusion correlated with pial collateral scores and canine neurobehavioral scores well. This canine stroke model with combined MCAO and ilICAB reported here were proven to be highly feasible and reproducible.

The classical theorem of Zareckii about regular relations is slightly extended and an intrinsic characterization of regularity is given. Based on the extended Zareckii theorem and the intrinsic characterization of regularity, we give a characterization of the strict complete regularity of ordered spaces by means of a certain regular relation between the closed and the open upper sets. As an application, it is shown that a quasicontinuous domain endowed with the Lawson topology is strictly completely regular, provided that the Lawson-open lower sets are contained in the lower topology. By means of regular relations we present a new proof of the strict Tychonoff embedding theorem for strictly completely regular ordered spaces.

Aim To evaluate the performance of the combination of diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for differentiating radiologically indeterminate malignant from benign orbital masses. Materials and methods Sixty-five patients with orbital masses (36 benign and 29 malignant) underwent DW and DCE MRI examinations for pre-treatment evaluation. The apparent diffusion coefficient (ADC) was derived from DW imaging data using the mono-exponential model. The volume transfer constant (K trans ), the flux rate constant between the extravascular extracellular space and the plasma (K ep ), and the extravascular extracellular volume fraction (V e ) were calculated using modified Tofts model. Differences in quantitative metrics were tested using independent-samples t test. Receiver operating characteristic (ROC) curve analyses were used to determine and compare the diagnostic ability of each significant metric. Results The malignant group demonstrated significantly lower ADC (0.711±0.260 versus 1.187±0.389, p ep values (1.265±0.637 versus 0.871±0.610, p =0.008) than the benign group. Optimal diagnostic performance (area under the ROC curve [AUC], 0.941; sensitivity, 0.966; specificity, 0.917) could be achieved using combined ADC and K ep values as the diagnostic index. The diagnostic performance of the combination of ADC and K ep was significantly better than K ep alone ( p =0.006). Compared with ADC alone, combined ADC and K ep values also showed higher AUC (0.941 versus 0.898), although the difference did not reach statistical significance ( p =0.220). Conclusion K ep and ADC could help to differentiate radiologically indeterminate malignant from benign orbital masses. The combination of DW and DCE MRI might improve the differentiating performance.