Application of Machine Learning and Deep Learning in Imaging of Ischemic Stroke

Timely analysis of imaging data is critical for diagnosis and decision-making for proper treatment strategy in the cases of ischemic stroke. Various efforts have been made to develop computer-assisted systems to improve the accuracy of stroke diagnosis and acute stroke triage. The widespread emergence of artificial intelligence technology has been integrated into the field of medicine. Artificial intelligence can play an important role in providing care to patients with stroke. In the past few decades, numerous studies have explored the use of machine learning and deep learning algorithms for application in the management of stroke. In this review, we will start with a brief introduction to machine learning and deep learning and provide clinical applications of machine learning and deep learning in various aspects of stroke management, including rapid diagnosis and improved triage, identifying large vessel occlusion, predicting time from stroke onset, automated ASPECTS (Alberta Stroke Program Early CT Score) measurement, lesion segmentation, and predicting treatment outcome. This work is focused on providing the current application of artificial intelligence techniques in the imaging of ischemic stroke, including MRI and CT.

Predictors of Catastrophic Outcome after Endovascular Thrombectomy in Elderly Patients with Acute Anterior Circulation Stroke

Predictors of a Favorable Outcome after Emergent Carotid Artery Stenting in Acute Anterior Circulation Stroke Patients

Purpose@#This study aimed to identify independent predictors of favorable outcomes associated with emergent carotid artery stenting (CAS) in patients with acute anterior circulation stroke. @*Materials and Methods@#This study included 93 patients with acute stroke who underwent emergent CAS to treat stenoocclusive lesions in the cervical internal carotid artery (ICA) within 6 hours of the onset of the associated symptoms. Data were compared between patients with and without favorable outcomes. The independent predictors of a favorable outcome were determined via logistic regression analysis (modified Rankin Scale 0–2 at 90 days). @*Results@#Intracranial tandem occlusion was noted in 81.7% of patients (76/93) among which (76/93), 55 of whom underwent intracranial recanalization therapy. Intracranial reperfusion was successful in 74.2% (69/93) and favorable outcomes were noted in 51.6% of patients (48/93). The mortality rate was 6.5% (6/93). In logistic regression analysis, diffusion-weighted imaging-Alberta Stroke Program Early CT Score [odds ratio (OR), 1.487; 95% confidence interval (CI), 1.018–2.173, p = 0.04], successful reperfusion (OR, 5.199; 95% CI, 1.566–17.265, p = 0.007), and parenchymal hemorrhage (OR, 0.042; 95% CI, 0.003–0.522, p = 0.014) were independently associated with a favorable outcome. @*Conclusion@#Baseline infarct size, reperfusion status, and parenchymal hemorrhage were independent predictors of favorable outcomes after emergent CAS to treat stenoocclusive lesions in the cervical ICA in patients with acute anterior circulation stroke.

Neural Mechanism of Second Language Processing in Korean-English Bilingual Children

PURPOSE@#To evaluate the neural mechanism of second language processing in Korean-English bilingual children using functional MRI (fMRI).@*MATERIALS AND METHODS@#The study was conducted on 20 Korean elementary school children who were learning English as a foreign language. fMRI was performed during short-passage comprehension tasks in Korean and English languages. We analyzed which brain areas were activated according to the language, English proficiency, and task difficulty.@*RESULTS@#Higher activities were observed in the dorsolateral prefrontal cortex, supplementary motor area, precentral gyrus, left basal ganglia, and left temporoparietal and occipital lobes during English comprehension than during Korean comprehension. The low English proficiency group showed higher activities than the high English proficiency group in the frontotemporal cortex, including the prefrontal cortex. Higher activities were observed in the right inferior frontal gyrus and right temporoparietal lobe during the English comprehension task of intermediate difficulty compared to that of low difficulty. However, the brain activities significantly decreased while performing a high-difficulty English task.@*CONCLUSION@#Brain activities significantly increased during English comprehension in the lower English proficiency group while performing an intermediate-difficulty task. However, brain activation decreased when the task difficulty exceeded the moderate comprehension level. These results suggest that a proper level of education is important to learn a second language.

Group B Streptococcus Meningitis Presenting as the Initial Symptom of a Recurrent Pituitary Adenoma

No abstract available.

Predictive Factors for Good Outcome and Mortality After Stent-Retriever Thrombectomy in Patients With Acute Anterior Circulation Stroke / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Predictive factors associated with stent-retriever thrombectomy for patients with acute anterior circulation stroke remain to be elucidated. This study aimed to investigate clinical and procedural factors predictive of good outcome and mortality after stent-retriever thrombectomy in a large cohort of patients with acute anterior circulation stroke. METHODS: We analyzed clinical and procedural data in 335 patients with acute anterior circulation stroke treated with stent-retriever thrombectomy. A good outcome was defined as a modified Rankin Scale score of 0 to 2 at 3 months. The associations between clinical, imaging, and procedural factors and good outcome and mortality, respectively, were evaluated using logistic regression analysis. RESULTS: Using multivariate analysis, age (odds ratio [OR], 0.965; 95% confidence interval [CI], 0.944-0.986; P=0.001), successful revascularization (OR, 4.658; 95% CI, 2.240-9.689; P<0.001), parenchymal hemorrhage (OR, 0.150; 95% CI, 0.049-0.460; P=0.001), and baseline NIHSS score (OR, 0.908; 95% CI, 0.855-0.965; P=0.002) were independent predictors of good outcome. Independent predictors of mortality were age (OR, 1.043; 95% CI, 1.002-1.086; P=0.041), successful revascularization (OR, 0.171; 95% CI, 0.079-0.370; P<0.001), parenchymal hemorrhage (OR, 2.961; 95% CI, 1.059-8.276; P=0.038), and a history of previous stroke/TIA (OR, 3.124; 95% CI, 1.340-7.281; P=0.008). CONCLUSIONS: Age, revascularization status, and parenchymal hemorrhage are independent predictors of both good outcome and mortality after stent retriever thrombectomy for acute anterior circulation stroke. In addition, NIHSS score on admission is independently associated with good outcome, whereas a history of previous stroke is independently associated with mortality.

Chlorfenapyr-Induced Toxic Leukoencephalopathy with Radiologic Reversibility: A Case Report and Literature Review

Chlorfenapyr is a widely used, moderately hazardous pesticide. Previous reports have indicated that chlorfenapyr intoxication can be fatal in humans. We reported the first non-fatal case of chlorfenapyr-induced toxic leukoencephalopathy in a 44-year-old female with resolution of extensive and abnormal signal intensities in white matter tracts throughout the brain, brain stem, and spinal cord on serial magnetic resonance imaging.

Chordoid Glioma with Intraventricular Dissemination: A Case Report with Perfusion MR Imaging Features

Chordoid glioma is a rare low grade tumor typically located in the third ventricle. Although a chordoid glioma can arise from ventricle with tumor cells having features of ependymal differentiation, intraventricular dissemination has not been reported. Here we report a case of a patient with third ventricular chordoid glioma and intraventricular dissemination in the lateral and fourth ventricles. We described the perfusion MR imaging features of our case different from a previous report.

Successful Cross-circulation Stent-Retriever Embolectomy Through Posterior Communicating Artery for Acute MCA Occlusion by Using Trevo XP ProVue / 신경중재치료의학

Acute ischemic stroke due to embolic occlusion of the middle cerebral artery (MCA) in patients with chronic ipsilateral internal carotid artery (ICA) occlusion is quite rare. Several previous reports demonstrated that intra-arterial (IA) thrombolytic therapy or aspiration thrombectomy using the cross-circulation technique via an alternative collateral pathway is feasible in acute stroke patients with an unfavorable direct route to the occluded sites. However, stent-retriever embolectomy via the cross-circulation approach has not been reported in the literature. The present paper reports the first case of successful stent-retriever embolectomy for acute MCA occlusion via the patent posterior communicating artery (PComA) by using Trevo XP ProVue stent-retriever in a patient with acute MCA stroke and chronic occlusion at the origin site of the ipsilateral ICA.