Efficacy and Safety of Endovascular Treatment in Patients with Internal Carotid Artery Occlusion and Collateral Middle Cerebral Artery Flow

OBJECTIVE: In patients with internal carotid artery (ICA) occlusion, collateral middle cerebral artery (MCA) flow has a protective role against ischemia. However, some of these patients may experience initial major neurological deficits and major worsening on following days. Thus, we investigated the safety and efficacy of endovascular treatment (EVT) for ICA occlusion with collateral MCA flow by comparing clinical outcomes of medical treatment versus EVT.METHODS: The inclusion criteria were as follows : 1) acute ischemic stroke with ICA occlusion and presence of collateral MCA flow on transfemoral cerebral angiography (TFCA) and 2) hospital arrival within 12 hours from symptom onset. The treatment strategy was made by the attending physician based on the patient’s clinical status and results of TFCA.RESULTS: Eighty-one patients were included (30 medical treatment, 51 EVT). The EVT group revealed a high incidence of intracranial ICA occlusion, longer ipsilesional MCA contrast filling time, and a similar rate of favorable clinical outcome despite a higher mean baseline the National Institutes of Health Stroke Scale (NIHSS) score. By binary logistic regression analysis, intravenous recombinant tissue plasminogen activator and EVT were independent predictors of favorable clinical outcome. In subgroup analysis based on stroke etiology, the non-atherosclerotic group showed a higher baseline NIHSS score, higher incidence of EVT, and a higher rate of distal embolization during EVT in comparison with the atherosclerotic group.CONCLUSION: In patients with ICA occlusion and collateral MCA flow, decisions regarding treatment strategy based on TFCA can help achieve favorable clinical outcomes. EVT strategy with respect to etiology of ICA occlusion might help achieve better angiographic outcomes.

Clinical Impact of Intracerebral Hemorrhage after Hyperacute Extracranial Stenting in Patients with Ischemic Stroke / 신경중재치료의학

PURPOSE: Emergent intracranial occlusions causing acute ischemic stroke are often related to extracranial atherosclerotic stenosis. This study aimed to investigate the association between post-procedure intracerebral hemorrhage (ICH) and emergent extracranial artery stenting and assess their effects on clinical outcomes in patients with acute ischemic stroke. MATERIALS AND METHODS: We retrospectively analyzed patients undergoing hyperacute endovascular treatment for cervicocephalic vascular occlusion in three Korean hospitals between January 2011 and February 2016. Patients who had extracranial artery involvement and were treated from 24 hours of symptom onset to puncture were included in this study, and they were divided into the extracranial stenting (ES) and non-ES groups. Any type of petechial hemorrhages and parenchymal hematoma was defined as ICH for the current study. RESULTS: In total, 76 patients were included in this study. Among them, 56 patients underwent ES, and 20 patients did not. Baseline characteristics, risk factors, laboratory data, treatment methods, successful reperfusion rates, and baseline stenotic degrees of extracranial internal carotid artery did not differ between these two groups. However, atrial fibrillation was more frequent in patients without than with ES (P=0.002), and post-procedure ICH was more frequent in patients with than without ES (P=0.035). Logistic regression models revealed that ES was independently associated with post-procedure ICH (odds ratio [OR], 7.807; 95% confidence interval [CI], 1.213–50.248; P=0.031), and ICH was independently associated with poor clinical outcomes (OR, 0.202; 95% CI, 0.054–0.759; P=0.018); however, ES itself was not associated with clinical outcomes (OR, 0.530; 95% CI, 0.117–2.395; P=0.409). Notably, ICH and ES had interaction for predicting good outcomes (P=0.041). CONCLUSION: Post-procedure ICH was associated with ES and poor clinical outcomes. Therefore, ES should be cautiously considered in patients with hyperacute stroke.

Efficacy and Safety of Endovascular Treatment in Patients with Internal Carotid Artery Occlusion and Collateral Middle Cerebral Artery Flow

OBJECTIVE: In patients with internal carotid artery (ICA) occlusion, collateral middle cerebral artery (MCA) flow has a protective role against ischemia. However, some of these patients may experience initial major neurological deficits and major worsening on following days. Thus, we investigated the safety and efficacy of endovascular treatment (EVT) for ICA occlusion with collateral MCA flow by comparing clinical outcomes of medical treatment versus EVT. METHODS: The inclusion criteria were as follows : 1) acute ischemic stroke with ICA occlusion and presence of collateral MCA flow on transfemoral cerebral angiography (TFCA) and 2) hospital arrival within 12 hours from symptom onset. The treatment strategy was made by the attending physician based on the patient’s clinical status and results of TFCA. RESULTS: Eighty-one patients were included (30 medical treatment, 51 EVT). The EVT group revealed a high incidence of intracranial ICA occlusion, longer ipsilesional MCA contrast filling time, and a similar rate of favorable clinical outcome despite a higher mean baseline the National Institutes of Health Stroke Scale (NIHSS) score. By binary logistic regression analysis, intravenous recombinant tissue plasminogen activator and EVT were independent predictors of favorable clinical outcome. In subgroup analysis based on stroke etiology, the non-atherosclerotic group showed a higher baseline NIHSS score, higher incidence of EVT, and a higher rate of distal embolization during EVT in comparison with the atherosclerotic group. CONCLUSION: In patients with ICA occlusion and collateral MCA flow, decisions regarding treatment strategy based on TFCA can help achieve favorable clinical outcomes. EVT strategy with respect to etiology of ICA occlusion might help achieve better angiographic outcomes.

Gerstmann-Sträussler-Scheinker Disease (Pro102Leu) Presenting as Rapidly Progressive Dementia

Genetic prion diseases account for about 10-15% of all cases of human prion disease and are caused by mutations in the prion protein gene. Gerstmann-Sträussler-Scheinker (GSS) disease is a rare genetic prion disease, which is characterized by slowly progressive cerebellar ataxia and the occurrence of cognitive decline in the later stage. P102L is the most common mutation in GSS. We report a patient with a P102L mutation that initially manifested as rapidly progressive dementia without cerebellar symptoms.

A Case of Rapid Progressive Neurosyphilis in Patient with Ankylosing Spondylitis Who Is Treating Anti-interleukin 17A Monoclonal Antibody, Secukinumab

Anti-interleukin 17A agent, secukinumab is remarkably effective for treating patients with ankylosing spondylitis. However, the main safety concern of secukinumab is an increased risk of infection. Generally, neurosyphilis occurs a few years after the primary syphilitic infection. Rare cases of progressing to neurosyphilis with a much lower latency were reported. We report a case of rapid progressive neurosyphilis involving hearing loss in both ears in a patient with ankylosing spondylitis who was treated with secukinumab.

Re-transmissibility of mouse-adapted ME7 scrapie strain to ovine PrP transgenic mice

Scrapie is a mammalian transmissible spongiform encephalopathy or prion disease that predominantly affects sheep and goats. Scrapie has been shown to overcome the species barrier via experimental infection of other rodents. To confirm the re-transmissibility of the mouse-adapted ME7 scrapie strain to ovine prion protein (PrP) transgenic mice, mice of an ovinized transgenic mouse line carrying the Suffolk sheep PrP gene that contained the A₁₃₆ R₁₅₄ Q₁₇₁/ARQ allele were intracerebrally inoculated with brain homogenates obtained from terminally ill ME7-infected C57BL/6J mice. Herein, we report that the mouse-adapted ME7 scrapie strain was successfully re-transmitted to the transgenic mice expressing ovine PrP. In addition, we observed changes in the incubation period, glycoform profile, and pattern of scrapie PrP (PrP(Sc)) deposition in the affected brains. PrP(Sc) deposition in the hippocampal region of the brain of 2nd-passaged ovine PrP transgenic mice was accompanied by plaque formation. These results reveal that the mouse-adapted ME7 scrapie strain has the capacity to act as a template for the conversion of ovine normal monomeric precursors into a pathogenic form in ovine PrP transgenic mice. The change in glycoform pattern and the deposition of plaques in the hippocampal region of the brain of the 2nd-passaged PrP transgenic mice are most likely cellular PrP species dependent rather than being ME7 scrapie strain encoded.

Prognosis of Acute Intracranial Atherosclerosis-Related Occlusion after Endovascular Treatment / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Little is known about prognosis after endovascular therapy (EVT) for acute large artery occlusion (LAO) caused by underlying intracranial atherosclerotic stenosis (ICAS). Therefore, we investigated the prognosis following EVT according to the underlying etiology of LAO. METHODS: Patients from the Acute Stroke due to Intracranial Atherosclerotic occlusion and Neurointervention-Korean Retrospective (ASIAN KR) registry (n=720) were included if their occlusion was in the intracranial anterior circulation and their onset-to-puncture time was < 24 hours. Occlusion was classified according to etiology as follows: no significant stenosis after recanalization (Embolic group), and fixed significant focal stenosis in the occlusion site with flow impairment or re-occlusion observed during EVT (ICAS group). Patients were excluded when significant extracranial carotid lesions existed, and when the intracranial occlusion was intractable to EVT so that the etiology was undetermined. The effect of angiographic etiologic classification on outcomes was evaluated using multivariable analysis that was adjusted for potential confounders. RESULTS: Among eligible patients (n=520), 421 and 99 were classified in the Embolic and ICAS groups, respectively. Patients in the Embolic and ICAS groups had similar successful reperfusion rates with EVT (79.6% vs. 76.8%, P=0.537) and 3-month functional independence (54.5% vs. 45.5%, P=0.104). In multivariable analysis, ICAS-related occlusion (odds ratio, 0.495; 95% confidence interval, 0.269 to 0.913; P=0.024) showed poorer 3-month functional independence compared to embolic occlusion. CONCLUSIONS: After EVT, patients with acute ICAS-related occlusion have relatively poor functional outcomes compared to those with embolic occlusion. Novel strategies need to be developed to improve EVT outcomes for ICAS occlusion.

Temporal Changes in Care Processes and Outcomes for Endovascular Treatment of Acute Ischemic Stroke: Retrospective Registry Data from Three Korean Centers / 신경중재치료의학

BACKGROUND AND PURPOSE: The purpose of the current study is to evaluate the influence of temporal patterns related to the availability of new endovascular treatment (EVT) devices on care processes and outcomes among patients with AIS. MATERIALS AND METHODS: We enrolled 720 consecutive patients (January 2011 to May 2016) in a retrospective registry, ASIAN KR, from three Korean hospitals, who received EVT for acute ischemic stroke (AIS) caused by cervicocephalic arterial occlusions. We performed period-to-period analyses based on stent retriever reimbursement and the availability of second-generation direct-aspiration devices (Period 1: January 2011–July 2014 vs. Period 2: August 2014–May 2016); time metrics and outcomes were compared when the onset-to-puncture time was <720 min among patients with EVT for intracranial occlusion. RESULTS: Period 2 had better post-EVT outcomes (3-month modified Rankin Scale 0–2 or equal to prestroke score, 48.3% vs. 60.2%, P=0.004), more successful reperfusion rates (modified Treatment In Cerebral Ischemia 2b–3, 74.2% vs. 82.2%, P=0.019), fewer subarachnoid hemorrhages (modified Fisher grade 3–4, 5.5% vs. 2.0%, P=0.034) and lower hemorrhagic transformation rates (any intracerebral hemorrhage, 35.3 vs. 22.7%, P=0.001) than Period 1. Compared to Period 1, Period 2 had a shorter door-to-puncture time (median 109 vs. 90 min, P<0.001), but longer onset-to-door time (129 vs. 143 min, P=0.057). CONCLUSION: Recent temporal improvements in post-EVT AIS outcomes in Korea are likely due to a combination of enhanced hospital care processes and administration of newer thrombectomy devices.

Endovascular Revascularization Therapy in a Patient with Acute Ischemic Stroke due to Intracranial Multiple Large-vessel Occlusion

Multiple large-vessel occlusive stroke is rare in clinical practice, and its prognosis is usually poor. A 58-year-old female with atrial fibrillation experienced left hemiparesis and drowsy mentality, and was diagnosed with ischemic stroke due to acute occlusion of right carotid and basilar artery. Successful mechanical thrombectomy was performed for both occlusions with clot aspiration technique, and favorable outcome was achieved at 3-month. Endovascular revascularization therapy in acute occlusion of multiple large vessels seems feasible when favorable outcome can be expected.

Forced Arterial Suction Thrombectomy Using Distal Access Catheter in Acute Ischemic Stroke / 신경중재치료의학

Historical innovations in mechanical thrombectomy devices and strategies for ischemic stroke have resulted in improved angiographic outcomes and better clinical outcomes. Various devices have been used, but the two most common approaches are aspiration thrombectomy and stent-retrieval thrombectomy. Aspiration thrombectomy has advanced from the traditional Penumbra system to forced arterial suction thrombectomy and a direct aspiration first-pass technique. Newer generation aspiration catheters with flexible distal tips and a larger bore have demonstrated faster and better recanalization relative to older devices. Recently, several species of distal access catheters have similar structural characteristics to the Penumbra reperfusion catheter. Therefore, we used the distal access catheter for forced arterial suction thrombectomy in three patients with acute ischemic stroke. In each case, we achieved fast and complete recanalization without significant complications. Forced arterial suction thrombectomy using a distal access catheter might provide another option for mechanical thrombectomy in patients with acute ischemic stroke.

Impact of Baseline Ischemia on Outcome in Older Patients Undergoing Endovascular Therapy for Acute Ischemic Stroke

BACKGROUND AND PURPOSE: The outcome for older stroke patients who undergo endovascular revascularization remains unsatisfactory. We aimed to determine the effect of the extent of baseline ischemia on outcome according to age, testing the hypothesis that the restorative capacity for recovery is only marginal in older patients. METHODS: Two hundred and thirteen patients who underwent endovascular revascularization due to occlusion in the M1 segment of the middle cerebral artery (with or without internal carotid artery occlusions) were selected for analysis. Patients were categorized into three age groups: group A (75 years). Using pretreatment diffusion-weighted imaging (DWI), the Alberta Stroke Program Early CT Score (ASPECTS) and lesion volume were independently measured and analyzed in relation to a favorable outcome. RESULTS: A favorable outcome was achieved in 111 of 213 patients overall: in 60 of the 94 (63.8%) patients in group A, in 36 of the 70 (51.4%) patients in group B, and in 15 of the 49 (30.6%) patients in group C (p=0.001). In older stroke patients (group C), a DWI ASPECTS ≥9 and lesion volume ≤5 mL were found to predict a favorable outcome, which was more restrictive than the cutoffs for their younger counterparts (groups A and B; DWI ASPECTS ≥8 and lesion volume ≤20 mL). CONCLUSIONS: The age-adjusted pretreatment DWI lesion volume and ASPECTS may represent useful surrogate markers for functional outcome according to age. The use of more-restrictive inclusion criteria for older stroke patients could be warranted, although larger studies are necessary to confirm these findings.

Efficacy of Proximal Aspiration Thrombectomy for Using Balloon-Tipped Guide Catheter in Acute Intracranial Internal Carotid Artery Occlusion

OBJECTIVE: Mechanical thrombectomy (MT) for acute intracranial internal carotid artery (ICA) occlusion is often complicated by difficult revascularization and non-involved territory embolization possibly related with larger clot-burden. This study aims to evaluate the efficacy of proximal aspiration thrombectomy (PAT) using a balloon-tipped guide catheter for clot-burden reduction in such cases with period-to-period analysis (period 1 : standard MT without PAT; period 2 : PAT first, then standard MT for the remaining occlusion). METHODS: Eighty-six patients who underwent MT for acute intracranial ICA occlusion were included in this analysis from the prospectively maintained stroke registry (33 patients in period 1 and 53 in period 2). In period 2, 'responder' was defined as a case where some amount of clot was retrieved by PAT and the following angiography showed partial or full recanalization. RESULTS: Fifteen of fifty-three patients in period 2 (28.3%) were 'responders' to PAT. There was a significantly higher incidence of atrial fibrillation in the 'responder' subgroup. Period 2 showed a significantly shorter puncture-to-reperfusion time (94.5 minutes vs. 56.0 minutes; p=0.002), a significantly higher Thrombolysis in Cerebral Infarction of 2b-3 reperfusion (45.5% vs. 73.6%; p=0.009), but only a trend for better 3-month favorable outcome (mRS 0-2; 36.4% vs. 54.7%; p=0.097). There was no increase in the incidence of procedure-related complications or intracranial hemorrhage in period 2. CONCLUSION: A strategy of PAT before standard MT may result in shorter puncture-to-reperfusion time and better angiographic outcome than a strategy of standard MT for acute intracranial ICA occlusion.

Cervicofacial Lymphatic Malformations: A Retrospective Review of 40 Cases

BACKGROUND: Lymphatic malformation (LM) is a form of congenital vascular malformation with a low incidence. Although LM has been studied, no consensus has emerged regarding its cause or treatment. METHODS: In this study, we retrospectively evaluated 40 patients who visited our vascular anomalies center for the treatment of cervicofacial LM, which is a common manifestation of LM. The medical records of patients over a period of 12 years were reviewed and analyzed for commonalities regarding the diagnosis and the results of treatment. RESULTS: Suspected cervicofacial LM was confirmed through imaging studies. No difference in incidence was observed according to sex, and 73% of patients first presented with symptoms before the age of two years. The left side and the V2-V3 area were most commonly affected. No significant differences in incidence were observed among the macrocystic, microcystic, and combined types of LM. A total of 28 out of 36 patients received sclerotherapy as the first choice of treatment, regardless of the type of lesion. Complete resolution was achieved in only 25% of patients. CONCLUSIONS: LM is important to confirm the diagnosis early and to choose an appropriate treatment strategy according to the stage of the disease and each individual patient's symptoms. When treatment is delayed or an incorrect treatment is administered, patient discomfort increases as the lesion gradually spreads. Therefore, more so than is the case for most other diseases, a team approach on a case-by-case basis is important for the accurate and appropriate treatment of LM.

The Relation of Blood Iron Level with Frontal Function in Children with Attention-Deficit/Hyperactivity Disorder / 신경정신의학

OBJECTIVES: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder showing many neuropsychological deficits. Many environmental risk factors have been thought to increase the risk for the disorder. We examined blood iron levels in children with ADHD and a control group to find an association between iron deficit and diagnosis, neuropsychological characteristics and clinical features. METHODS: An ADHD group (n=50) and control group (n=45) of children 6-12 years of age were recruited. Both groups were diagnosed by semi-structured interview, and they were evaluated using the Korean version of the ADHD Rating Scale (K-ARS), Korean version of IOWA Conner's Rating Scale (K-IOWA), intelligence quotient (IQ), and neurocognitive function tests (continuous performance test, children's color trails test, Stroop color-word test). Iron levels in blood were determined using the inductively coupled plasma mass spectrometry instrument. Independent t-test and correlation were used to determine the relation of blood iron levels with symptom ratings and neurocognitive function. Logistic regression was performed to determine the diagnostic value of blood iron levels. RESULTS: Blood iron levels were significantly lower in ADHD than in control and showed negative correlation with K-ARS and K-IOWA scores. Blood iron levels showed positive association with IQ and Stroop color-word test results and negative association with results of continuous performance testing. Low blood iron levels predicted the diagnosis of ADHD. CONCLUSION: Lower levels of blood iron were associated with ADHD symptom severity, IQ, and frontal lobe-mediated neurocognitive function. As blood iron levels may influence ADHD, measurement of iron levels in blood may be useful for evaluation of symptoms and neurocognitive function in ADHD.

Real-Time Quaking-Induced Conversion Analysis for the Diagnosis of Sporadic Creutzfeldt-Jakob Disease in Korea

BACKGROUND AND PURPOSE: The level of 14-3-3 protein in the cerebrospinal fluid (CSF) is increased in Creutzfeldt-Jakob disease (CJD) patients, which has led to it being used as a clinical biomarker for the ante-mortem diagnosis of human prion diseases. However, the specificity of the 14-3-3 protein is less reliable for CJD diagnosis. Newly developed assays including real-time quaking-induced conversion (RT-QuIC) have made it possible to detect the PrPSc-like abnormal prion isoform with a high sensitivity in animal and human specimens that might contain a minute amount of PrP(Sc) due to in vitro prion replication. METHODS: This study applied a highly sensitive RT-QuIC assay using recombinant human PrP to detect PrP(Sc) in the CSF of 81 patients with sporadic CJD (sCJD) in Korea. RESULTS: RT-QuIC analysis of the CSF samples based on the expression levels of 14-3-3 and total tau proteins revealed positivity in 62 of 81 sCJD patients (sensitivity of 76.5%) but no positive results in the 100 non-CJD patients. CONCLUSIONS: The sensitivity of the RT-QuIC in this study was similar to that in some previous reports, and the specificity of RT-QuIC was higher than that of 14-3-3 in CSF, suggesting that RT-QuIC analysis can complement the weakness of the specificity of 14-3-3 for the diagnosis of sCJD. These results indicate that RT-QuIC might be very useful for the rapid and specific diagnosis of sCJD and provide a practical novel method for the ante-mortem diagnosis of human prion diseases.

Forced Arterial Suction Thrombectomy of Septic Embolic Middle Cerebral Artery Occlusion Due to Infective Endocarditis: an Illustrative Case and Review of the Literature / 신경중재치료의학

In acute ischemic stroke patients with major intracranial vessel occlusion due to infective endocarditis, treatment modalities are not well established. A 40-year-old woman presented with acute stroke due to left middle cerebral artery occlusion. She was successfully treated with intra-arterial mechanical thrombectomy, and the subsequent clinical outcome was favorable. Pathological analysis of the retrieved clots showed septic thrombi containing gram-positive cocci. Based on literature review and the present case regarding treatment strategies for patients with septic embolic stroke, pharmacological thrombolysis might increase the risk of hemorrhagic complications, which might alter clinical outcome. Therefore, we can consider intra-arterial mechanical thrombectomy as a first-line treatment option in patients with acute stroke resulting from infective endocarditis.

Growth Hormone-Releaser Diet Attenuates Cognitive Dysfunction in Klotho Mutant Mice via Insulin-Like Growth Factor-1 Receptor Activation in a Genetic Aging Model

BACKGROUND: It has been recognized that a defect in klotho gene expression accelerates the degeneration of multiple age-sensitive traits. Accumulating evidence indicates that aging is associated with declines in cognitive function and the activity of growth hormone (GH)/insulin-like growth factor-1 (IGF-1). METHODS: In this study, we examined whether a GH-releaser diet could be effective in protecting against cognitive impairment in klotho mutant mice. RESULTS: The GH-releaser diet significantly induced the expression of IGF-1 and IGF-1 receptors in the hippocampus of klotho mutant mice. Klotho mutant mice showed significant memory impairments as compared with wild-type mice. In addition, the klotho mutation significantly decreased the expression of cell survival/antiapoptotic factors, including phospho-Akt (p-Akt)/phospho-glycogen synthase kinase3beta (p-GSK3beta), phospho-extracellular signal-related kinase (p-ERK), and Bcl-2, but significantly increased those of cell death/proapoptotic factors, such as phospho-c-jun N-terminal kinase (p-JNK), Bax, and cleaved caspase-3 in the hippocampus. Treatment with GH-releaser diet significantly attenuated both decreases in the expression of cell survival/antiapoptotic factors and increases in the expression of cell death/proapoptotic factors in the hippocampus of klotho mutant mice. In addition, klotho mutation-induced oxidative stress was significantly attenuated by the GH-releaser diet. Consequently, a GH-releaser diet significantly improved memory function in the klotho mutant mice. GH-releaser diet-mediated actions were significantly reversed by JB-1, an IGF-1 receptor antagonist. CONCLUSION: The results suggest that a GH-releaser diet attenuates oxidative stress, proapoptotic changes and consequent dysfunction in klotho mutant mice by promoting IGF-1 expression and IGF-1 receptor activation.

Genetic Studies in Human Prion Diseases

Human prion diseases are fatal neurodegenerative disorders that are characterized by spongiform changes, astrogliosis, and the accumulation of an abnormal prion protein (PrP(Sc)). Approximately 10%-15% of human prion diseases are familial variants that are caused by pathogenic mutations in the prion protein gene (PRNP). Point mutations or the insertions of one or more copies of a 24 bp repeat are associated with familial human prion diseases including familial Creutzfeldt-Jakob disease (CJD), Gerstmann-Straussler-Scheinker syndrome, and fatal familial insomnia. These mutations vary significantly in frequency between countries. Here, we compare the frequency of PRNP mutations between European countries and East Asians. Associations between single nucleotide polymorphisms (SNPs) of several candidate genes including PRNP and CJD have been reported. The SNP of PRNP at codon 129 has been shown to be associated with sporadic, iatrogenic, and variant CJD. The SNPs of several genes other than PRNP have been showed contradictory results. Case-control studies and genome-wide association studies have also been performed to identify candidate genes correlated with variant and/or sporadic CJD. This review provides a general overview of the genetic mutations and polymorphisms that have been analyzed in association with human prion diseases to date.

Safe Implementation of Mechanical Thrombectomy in Acute Stroke Patients with Major Arterial Occlusion and Concomitant Subdural Hematoma / 신경중재치료의학

Mechanical thrombectomy (MT) alone in cases of large-vessel acute ischemic stroke (AIS) with a concomitant subdural hematoma (SDH) seems feasible and safe, but there's still a lack of evidence in the clinical literature. We report three cases of AIS with SDH, of which MT was performed with successful recanalization and no major changes in SDH: two elderly men with acute traumatic SDH and one man with incidental chronic SDH. (1) A 67-year-old man with acute traumatic SDH in the right side developed right middle cerebral artery (MCA) stroke, (2) a 72-year-old man with chronic SDH in the left side developed right MCA stroke, and (3) a 76-year-old-man with acute traumatic SDH in the right side developed top-of-basilar artery syndrome. As for AIS patients with a SDH, MT may be the only feasible and safe treatment option.

Inadvertent Self-Detachment of Solitaire AB Stent during the Mechanical Thrombectomy for Recanalization of Acute Ischemic Stroke: Lessons Learned from the Removal of Stent via Surgical Embolectomy

We recently experienced self-detachment of the Solitaire stent during mechanical thrombectomy of acute ischemic stroke. Then, we tried to remove the detached stent and to recanalize the occlusion, but failed with endovascular means. The following diffusion weighted image MRI revealed no significant increase in infarction size, therefore, we performed surgical removal of the stent to rescue the patient and to elucidate the reason why the self-detachment occurred. Based upon the operative findings, the stent grabbed the main thrombi but inadvertently detached at a severely tortuous, acutely angled, and circumferentially calcified segment of the internal carotid artery. Postoperative angiography demonstrated complete recanalization of the internal carotid artery. The patient's neurological deficits gradually improved, and the modified Rankin scale score was 2 at three months after surgery. In the retrospective case review, bone window images of the baseline computed tomography (CT) scan corresponded to the operative findings. According to this finding, we hypothesized that bone window images of a baseline CT scan can play a role in terms of anticipating difficult stent retrieval before the procedure.