Hye Seon Jeong

Therapeutic Hypothermia After Recanalization in Patients With Acute Ischemic Stroke

Background and Purpose— Therapeutic hypothermia improves outcomes in experimental stroke models, especially after ischemia-reperfusion injury. We investigated the clinical and radiological effects of therapeutic hypothermia in acute ischemic stroke patients after recanalization. Methods— A prospective cohort study at 2 stroke centers was performed. We enrolled patients with acute ischemic stroke in the anterior circulation with an initial National Institutes of Health Stroke Scale ≥10 who had successful recanalization (≥thrombolysis in cerebral ischemia, 2b). Patients at center A underwent a mild hypothermia (34.5°C) protocol, which included mechanical ventilation, and 48-hour hypothermia and 48-hour rewarming. Patients at center B were treated according to the guidelines without hypothermia. Cerebral edema, hemorrhagic transformation, good outcome (3-month modified Rankin Scale, ⩽2), mortality, and safety profiles were compared. Potential variables at baseline and during the therapy were analyzed to evaluate for independent predictors of good outcome. Results— The hypothermia group (n=39) had less cerebral edema (P=0.001), hemorrhagic transformation (P=0.016), and better outcome (P=0.017) compared with the normothermia group (n=36). Mortality, hemicraniectomy rate, and medical complications were not statistically different. After adjustment for potential confounders, therapeutic hypothermia (odds ratio, 3.0; 95% confidence interval, 1.0–8.9; P=0.047) and distal occlusion (odds ratio, 7.3; 95% confidence interval; 1.3–40.3; P=0.022) were the independent predictors for good outcome. Absence of cerebral edema (odds ratio, 5.4; 95% confidence interval, 1.6–18.2; P=0.006) and no medical complications (odds ratio, 9.3; 95% confidence interval, 2.2–39.9; P=0.003) were also independent predictors for good outcome during the therapy. Conclusions— In patients with ischemic stroke, after successful recanalization, therapeutic hypothermia may reduce risk of cerebral edema and hemorrhagic transformation, and lead to improved clinical outcomes.

Interpretation of TCD spectral patterns detected during carotid artery stent interventions.

Purpose To classify transcranial Doppler (TCD) spectral patterns and analyze the significance of the patterns in the determination of hemodynamic alterations occurring during filter-protected carotid artery stent (CAS) procedures. Methods Data on middle cerebral artery (MCA) monitoring and post-CAS diffusion weighted magnetic resonance imaging (DWMRI) were reviewed for 53 patients (45 men; mean age 67.6±8.3 years) who underwent TCD evaluation before CAS and TCD monitoring during the procedure. TCD spectral patterns were classified according to the hemodynamic changes that occurred after different portions of the CAS procedures. The relationships among the spectral patterns and the frequency and location of new DWMRI lesions were analyzed. Results TCD spectral changes were classified into 4 patterns: (1) microemboli signals (53, 100%), (2) right-left collateral signals (31/53, 58%), (3) spectral suppression after balloon inflation (31/44, 70%), and (4) continuous spectral suppression after balloon removal (4/44, 9%). Even though microembolic signals were frequently observed during CAS, the new DWMRI lesions were more frequently observed outside of the cerebral territory (78%) rather than in the territory ipsilateral to CAS (47%). The presence of right-left collaterals was related to less severe balloon-related spectral suppression on ipsilateral MCA (p<0.05). Continuous spectral suppression appeared after stent deployment and balloon dilation and was immediately reversed after removal of the filter device. Conclusion The spectral patterns classified in the present study may prove useful in anticipating CAS procedure-related hemodynamic alterations. Close hemodynamic observation using these spectral patterns could be helpful in preventing serious complications during CAS.

Predictive Factors for Early Clinical Improvement after Intra-arterial Thrombolytic Therapy in Acute Ischemic Stroke

BACKGROUND In acute ischemic stroke, the speed of improvement after intra-arterial thrombolytic therapy (IAT)-mediated recanalization varies. This study aimed to identify clinical and radiological variables that are predictive of early improvement (EI) after IAT in acute ischemic stroke. METHODS This single-center retrospective cohort study included 141 consecutive patients who underwent IAT for terminal internal carotid and/or middle cerebral artery (MCA) occlusions. EI was defined as a National Institutes of Health Stroke Scale (NIHSS) score less than 3 or NIHSS score improvement of 8 points or more within 72 hours of IAT. The EI and non-EI groups were compared in terms of clinical and radiological findings before and after IAT. RESULTS Forty-nine patients showed EI (34.8%). Multivariate analysis revealed that atrial fibrillation (odds ratio [OR] .35, 95% confidence interval [CI] .14-.89, P = .028) and hyperdense MCA sign (OR .39, CI .15-.97, P = .042) were related with lack of EI. The independent EI predictors were less extensive parenchymal lesion on baseline computed tomography (OR 4.92, CI 1.74-13.9, P = .003), intermediate to good collaterals (OR 3.28, CI 1.16-9.31, P = .026), and recanalization within 6 hours of symptom onset (OR 5.2, CI 1.81-14.94, P = .002). EI associated with favorable outcomes (modified Rankin scale score 0-2) at discharge (88% versus 7%; P < .001) and 3 months after discharge (92% versus 18%; P < .001). CONCLUSIONS The clinical and radiological variables maybe useful for predicting EI and favorable long-term outcomes after IAT.

A comparison of stent-assisted mechanical thrombectomy and conventional intra-arterial thrombolysis for acute cerebral infarction.

Background and Purpose We evaluated whether stent-assisted thrombectomy (SAT) is safer or more clinically beneficial than aggressive mechanical clot disruption (AMCD) for patients with acute intracranial artery occlusion. Methods We retrospectively analyzed the clinical data of 72 patients (33 with SAT and 39 with AMCD) who underwent intra-arterial thrombolysis for acute intracranial artery occlusions. Procedure parameters, clinical outcomes, and incidence of complications were compared between the SAT and AMCD groups. Results The time interval to recanalization was shorter in SAT patients (69.2±39.6 minutes, mean±standard deviation) than in AMCD patients (94.4±48.0 minutes, p<0.05). Recanalization was achieved in more SAT patients (91%) than AMCD patients (80%), but with no statistically significance. Urokinase was used less frequently in SAT patients (21%) than in AMCD patients (92%, p<0.05), and the incidence of symptomatic hemorrhages was lower in SAT patients (3%) than in AMCD patients (18%, p<0.05). Device-related complications in SAT patients comprised two cases of stent fracture and one case of distal migration of a captured thrombus. The proportion of patients with good outcomes, defined as scores from 0 to 3 on the modified Rankin Scale, was similar in the two groups at discharge (SAT, 46%; AMCD, 39%), but significantly higher in the SAT group than in the AMCD group at 3 months (64% vs. 40%, p<0.05) and 6 months (67% vs. 42%, p<0.05) after discharge. Conclusions The outcomes and clinical parameters were better for SAT during thrombolytic procedures for acute intracranial artery occlusions than for AMCD for up to 6 months. However, some device-related complications occurred during stent interventions.

Impacts of Rapid Recanalization and Collateral Circulation on Clinical Outcome after Intraarterial Thrombolysis

Background and Purpose Rapid recanalization might improve clinical outcomes after intraarterial thrombolysis (IAT) for acute ischemic stroke patients with collateral circulation. We determined whether rapid recanalization and collateral circulation affect clinical outcomes after IAT. Methods We retrospectively evaluated the clinical and radiological data of 134 consecutive patients who underwent IAT for intracranial artery occlusion. The interval from symptom onset to recanalization after IAT (onset-to-recanalization time) as an estimate of the probability of good clinical outcome (modified Rankin scale 0-2) was calculated in patients with collateral circulation in the ischemic hemisphere, which was rated poor (0/1 American Society of Interventional and Therapeutic Neuroradiology criteria) or good (2-4). Changes in National Institute of Health Stroke Scale (NHISS) score before and after IAT and modified Rankins scale scores 3 months after discharge were compared with respect to onset-to-recanalization time. Results In patients with good collateral circulation, the estimated onset-to-recanalization time for a 0.5 probability of a good clinical outcome was 347 minutes; with poor collateral circulation, it was 172 minutes for a 0.2 probability of good clinical outcome. Outcome analyses according to onset-to-recanalization time showed patients recanalized <6 hours had lower NHISS scores (<4.5, 4.5-6, >6 hours of onset-to-recanalization time, and non-recanalization: 5.1, 6.9, 11.9, and 19.8, respectively) at discharge and higher percentages of good clinical outcome (69%, 66.7%, 21.9%, and 0%, respectively) 3 months after IAT. Conclusions The time window to expect a high probability of a good clinical outcome after IAT is highly dependent on the collateral circulation.

Intracranial Hemodynamic Stabilization Patterns After Stenting of Severe Stenosis in the Proximal Internal Carotid Artery

Purpose To evaluate intracranial hemodynamic stabilization patterns after carotid artery stenting (CAS) in patients having variable collateral developments before CAS. Methods The hemodynamic and angiographic data of 62 patients (58 men; mean age 68.0±8.4 years) who underwent CAS for unilateral proximal internal carotid artery stenosis were analyzed. The patients had transcranial Doppler examinations before and at 1 and 90 days after CAS. Patients were classified according to pre-CAS mean blood flow velocity (MBFV) of the ipsilateral middle cerebral artery (MCA): low (<30 cm/s; n=17), normal (30 to 48 cm/s; n=26), or high (>48 cm/s; n=19). The collaterals from contralateral anterior and/or posterior circulations prior to CAS, the stabilization pattern of MBFV, and the pulsatility index (PI) after CAS were compared across the 3 groups. Results The presence of collaterals was lowest in the low MBFV group (17.6% of patients) than in the normal (38.5%) or high (68.4%) MBFV groups (p=0.008). The low MBFV group exhibited an increase in MBFV and PI in the ipsilateral MCA at 1 and 90 days after CAS (p<0.05). By contrast, the high MBFV group exhibited a decrease in MBFV and no change in PI in the ipsilateral MCA up to 90 days after CAS (p<0.05). The normal MBFV group showed an increase in MBFV at post-CAS day 1 but a subsequent decrease at 90 days and an increase in PI in the ipsilateral MCA at 1 and 90 days post-CAS (p<0.05). Conclusion The pattern of post-CAS intracranial hemodynamic stabilization differs according to the pre-CAS MBFV in the ipsilateral MCA.

Refractory status epilepticus spontaneously resolved by parturition.

Status epilepticus (SE) in pregnancy is very rare, and there are only a few case reports of refractory SE (RSE) during pregnancy. The patient was a 27-year-old primigravida woman with a 21-year history of seizures from cortical dysplasia. At 23 weeks of pregnancy, the patient’s seizure frequency progressively increased, and the patient came to the ER in a confused mental state and with intermittent convulsive movements of her left arm. Electroencephalography (EEG) revealed repeated seizures. She was admitted to the ICU, and continuous EEG monitoring was done. Treatment was immediately started with various anti-SE medications, but her SE was not controlled. A cesarean section was done, and SE spontaneously stopped two weeks after the parturition. Parturition may be beneficial and the best treatment option in pregnant patients with RSE.

Two Patients Diagnosed with Juvenile Myoclonic Epilepsy by First-Ever Status Epilepticus in Adult Life

Juvenile myoclonic epilepsy (JME) is an idiopathic, age-related generalized epileptic syndrome. Status epilepticus (SE) in JME is very rare, and little is known about its etiology. We report 2 cases of adult patients, retrospectively diagnosed as JME by non convulsive status epilepticus which occurred for the first time. One patient was a 52-year-old woman who was presented with confusion and brief generalized tonic-clonic seizure (GTCS) for the first time. The other patient, a 39 year-old woman, visited the ER with transient LOC following confused mental state. Electroencephalograms of both patients repetitively showed generalized polyspikes and slow waves which were disappeared after IV injection of lorazepam. With careful history taking, both of them the patients were diagnosed as JME, and the seizures stopped just after sodium valproate medication. NCSE in patients with JME is rare but detailed history taking and suspicion of the disorder is helpful for diagnosis.

Transient global amnesia with post-hyperventilation temporal sharp waves—A case report

We report a 55-year-old woman, who presented with transient amnesia for 7h following underwater swimming. There was no evidence of neurological disturbance except global amnesia. Sharp waves in both temporal regions were registered during the initial EEG recording, which was accentuated by hyperventilation. Right hippocampal high signal intensity was observed in DWI performed 56 h after symptom onset. The sharp waves were all disappeared on follow-up EEG recordings.

High red blood cell composition in clots is associated with successful recanalization during intra-arterial thrombectomy

We evaluated the composition of individual clots retrieved during intra-arterial thrombectomy in relation to recanalization success, stroke subtype, and the presence of clot signs on initial brain images. We analyzed clot and interventional data from 145 retrieval trials performed for 37 patients (69.5±14.0 years, 20 men, large artery atherosclerosis, n = 7; cardioembolism, n = 22; undetermined etiology, n = 8) who had undergone intra-arterial thrombectomy. Rates of clot retrieval and successful recanalization (Arterial Occlusive Lesion score of 2–3) for separate retrieval trials were evaluated. The area occupied by red blood cell (RBC), fibrin/platelets, and white blood cell (WBC) was measured from digitized images of hematoxylin-eosin stained clots. Compositional differences were compared according to recanalization success, stroke subtype, and the presence of hyperdense clot sign on initial computed tomography and/or blooming artifact on magnetic resonance image. Of the 145 total retrieval trials (3.4±2.4 times per patient), clot was retrieved in 93 trials (64%), while recanalization was successful in 73 (50%). Fibrin/platelets (63%) occupied the greatest area in retrieved clots, followed by RBCs (33%) and WBCs (4%). Clots retrieved from successful recanalization exhibited higher RBC composition (37%) than those retrieved from non-recanalization trials (20%, p = 0.001). RBC composition was higher in cardioembolic stroke (38%) rather than large artery atherosclerosis (23%) and undetermined etiology (26%, p = 0.01). Clots exhibiting clot signs (40%) had higher RBC composition than those without clot signs (19%, p = 0.001). RBC-rich clots were associated with successful recanalization of intra-arterial thrombectomy, cardioembolic stroke, and the presence of clot-signs on initial brain images.