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Featured researches published by Sae-Yeon Won.


Journal of NeuroInterventional Surgery | 2017

Effect of heparin on secondary brain injury in patients with subarachnoid hemorrhage: an additional ‘H’ therapy in vasospasm treatment

Markus Bruder; Sae-Yeon Won; Sepide Kashefiolasl; Marlies Wagner; Nina Brawanski; Nazife Dinc; Volker Seifert; Juergen Konczalla

Objective Secondary brain injury leads to high morbidity and mortality rates in patients with aneurysmal subarachnoid hemorrhage (aSAH). However, evidence-based treatment strategies are sparse. Since heparin has various effects on neuroinflammation, microthromboembolism and vasomotor function, our objective was to determine whether heparin can be used as a multitarget prophylactic agent to ameliorate morbidity in SAH. Methods Between June 1999 and December 2014, 718 patients received endovascular treatment after rupture of an intracranial aneurysm at our institution; 197 of them were treated with continuous unfractionated heparin in therapeutic dosages after the endovascular procedure. We performed a matched pair analysis to evaluate the effect of heparin on cerebral vasospasm (CVS), cerebral infarction (CI), and outcome. Results The rate of severe CVS was significantly reduced in the heparin group compared with the control group (14.2% vs 25.4%; p=0.005). CI and multiple ischemic lesions were less often present in patients with heparin treatment. These effects were enhanced if patients were treated with heparin for >48 hours, but the difference was not significant. Favorable outcome at 6-month follow-up was achieved in 69% in the heparin group and in 65% in the control group. Conclusions Patients receiving unfractionated continuous heparin after endovascular aneurysm occlusion have a significant reduction in the rate of severe CVS, have CI less often, and tend to have a favorable outcome more often. Our findings support the potential beneficial effects of heparin as a multitarget therapy in patients with SAH, resulting in an additional ‘H’ therapy in vasospasm treatment.


Neurosurgical Focus | 2017

Acute subdural hematoma in patients on oral anticoagulant therapy: management and outcome

Sae-Yeon Won; Daniel Dubinski; Markus Bruder; Adriano Cattani; Volker Seifert; Juergen Konczalla

OBJECTIVE Isolated acute subdural hematoma (aSDH) is increasing in older populations and so is the use of oral anticoagulant therapy (OAT). The dramatic increase of OAT-with direct oral anticoagulants (DOACs) as well as with conventional anticoagulants-is leading to changes in the care of patients who present with aSDH while receiving OAT. The purpose of this study was to determine the management and outcome of patients being treated with OAT at the time of aSDH presentation. METHODS In this single-center, retrospective study, the authors analyzed 116 consecutive cases involving patients with aSDH treated from January 2007 to June 2016. The following parameters were assessed: patient characteristics, admission status, anticoagulation status, perioperative management, comorbidities, clinical course, and outcome as determined at discharge and through 6 months of follow-up. Oral anticoagulants were classified as thrombocyte inhibitors, vitamin K antagonists, and DOACs. Patients were stratified based on which type of medication they were taking, and subgroup analyses were performed. Predictors of unfavorable outcome at discharge and follow-up were identified. RESULTS Of 116 patients, 74 (64%) had been following an OAT regimen at presentation with aSDH. The patients who were taking oral anticoagulants (OAT group) were significantly older (OR 12.5), more often comatose 24 hours postoperatively (OR 2.4), and more often had ≥ 4 comorbidities (OR 3.2) than patients who were not taking oral anticoagulants (no-OAT group). Accordingly, the rate of unfavorable outcome was significantly higher in patients in the OAT group, both at discharge (OR 2.3) and at follow-up (OR 2.2). Of the patients in the OAT group, 37.8% were taking a thrombocyte inhibitor, 54.1% a vitamin K antagonist, and 8.1% DOACs. In all cases, OAT was stopped on discovery of aSDH. For reversal of anticoagulation, patients who were taking a thrombocyte inhibitor received desmopressin 0.4 μg/kg, 1-2 g tranexamic acid, and preoperative transfusion with 2 units of platelets. Patients following other oral anticoagulant regimens received 50 IU/kg of prothrombin complex concentrates and 10 mg of vitamin K. There was no significant difference in the rebleeding rate between the OAT and no-OAT groups. The in-hospital mortality rate was significantly higher for patients who were taking a thrombocyte inhibitor (OR 3.3), whereas patients who were taking a vitamin K antagonist had a significantly higher 6-month mortality rate (OR 2.7). Patients taking DOACs showed a tendency toward unfavorable outcome, with higher mortality rates than patients on conventional OAT or patients in the vitamin K antagonist subgroup. Independent predictors for unfavorable outcome at discharge were comatose status 24 hours after surgery (OR 93.2), rebleeding (OR 9.8), respiratory disease (OR 4.1), and infection (OR 11.1) (Nagelkerke R2 = 0.684). Independent predictors for unfavorable outcome at follow-up were comatose status 24 hours after surgery (OR 12.7), rebleeding (OR 3.1), age ≥ 70 years (OR 3.1), and 6 or more comorbidities (OR 3.1, Nagelkerke R2 = 0.466). OAT itself was not an independent predictor for worse outcome. CONCLUSIONS An OAT regimen at the time of presentation with aSDH is associated with increased mortality rates and unfavorable outcome at discharge and follow-up. Thrombocyte inhibitor treatment was associated with increased short-term mortality, whereas vitamin K antagonist treatment was associated with increased long-term mortality. In particular, patients on DOACs were seriously affected, showing more unfavorable outcomes at discharge as well as at follow-up. The suggested medical treatment for aSDH in both OAT and no-OAT patients seems to be effective and reasonable, with comparable rebleeding and favorable outcome rates in the 2 groups. In addition, prior OAT is not a predictor for aSDH outcome.


World Neurosurgery | 2016

Dislocated Pacemaker Electrode Simulating Focal Epileptic State in a Patient with Subdural Hematoma—Case Report and Review of the Literature

Sae-Yeon Won; Markus Bruder; Jan Mersmann; Volker Seifert; Christian Senft

BACKGROUND Due to demographic changes, the number of patients with traumatic brain injury carrying a cardiac resynchronization therapy device is increasing. One of the common complications of subdural hematoma (SDH) is epilepsy, whereas one of the most frequent early complications after cardiac resynchronization therapy device implantation is lead dislocation. The latter might then cause unintended skeletal muscle stimulation that might be misinterpreted in seizure-prone patients. CASE DESCRIPTION An 86-year-old female patient with an initially conservatively treated SDH on the right side presented with a tonic muscle contraction in her left arm 2 weeks after the trauma not responding to antiepileptic therapy. A computed tomography scan revealed residual hematoma on the right side with regular, time-dependent resorption. The muscle contraction was misdiagnosed as a focal epileptic state leading to evacuation of the chronic SDH. Additionally, routine postoperative chest radiographs were performed. Postoperatively, the tonic muscle contraction in her arm persisted. Chest radiographs revealed a dislocation of the left ventricular electrode, which appeared retracted into the left subclavian vein, next to the plexus brachialis. After deactivating the electrode, the alleged focal state ceased. CONCLUSIONS In case of refractory treatment of epilepsy, dislocation of pacemaker electrodes is a, most certainly, rare but possible differential diagnosis. Confirmation of electrode position and function is easily and quickly feasible and will help prevent futile seizure-directed therapy.


World Neurosurgery | 2018

The Value of Computed Tomography Imaging of the Head After Ventriculoperitoneal Shunt Surgery in Adults

Bedjan Behmanesh; Fee Keil; Daniel Dubinski; Sae-Yeon Won; Johanna Quick-Weller; Volker Seifert; Florian Gessler

BACKGROUND Patients with a ventriculoperitoneal shunt for hydrocephalus often undergo multiple follow-up computed tomography (CT) scans of the head, increasing the risk for long-term effects of ionizing radiation. The purpose of our study was to evaluate the necessity as a routine diagnostic procedure and cost analysis of routine postoperative CT scan of the head after ventriculoperitoneal shunt surgery. METHODS In this study, we comprised adults with ventriculoperitoneal shunt operations who underwent early CT scans within 48 hours postoperatively. We reviewed the correlation between revision surgery rate and the experience of surgeons who performed surgery and provided a cost analysis. RESULTS In total, 479 surgeries were performed in 439 patients. Early revision surgery was performed in 11 (2.3%) patients. Reason for revision surgery was malposition in 9 cases and intracerebral hemorrhage in 2 patients. There was no significant correlation between the surgeons experience and the rate of revision surgery. Placement of the ventricular catheter via an approach other than a standard right or left frontal burr hole resulted in risk of need for surgical shunt revision (P ≥ 0.002, odds ratio 54, confidence interval 13.5-223). A total of 468 CT scans of the head revealed a normal finding; thus, ∼


PLOS ONE | 2018

The clinical relevance of ABO blood type in 100 patients with acute subdural hematoma

Daniel Dubinski; Sae-Yeon Won; Bedjan Behmanesh; Nina Brawanski; Christof Geisen; Volker Seifert; Christian Senft; Jürgen Konczalla

562,000 could be saved by omitting postoperative head CT scans. CONCLUSIONS Routine postoperative head CT scans after fentriculoperitoneal shunting are not necessary in all cases. The reduction of exposure to ionization radiation and the beneficial economic factor are main advantages.


PLOS ONE | 2018

Excellent accuracy of ABC/2 volume formula compared to computer-assisted volumetric analysis of subdural hematomas

Sae-Yeon Won; Andrea Zagorcic; Daniel Dubinski; Johanna Quick-Weller; Eva Herrmann; Volker Seifert; Juergen Konczalla

Objective The correlation of depleted blood through midline shift in acute subdural hematoma remains the most reliable clinical predictor to date. On the other hand, patient’s ABO blood type has a profound impact on coagulation and hemostasis. We conducted this study to evaluate the role of patient’s blood type in terms of incidence, clinical course and outcome after acute subdural hematoma bleeding. Methods 100 patients with acute subdural hematoma treated between 2010 and 2015 at the author’s institution were included. Baseline characteristics and clinical findings including Glasgow coma scale, Glasgow outcome scale, hematoma volume, rebleeding, midline shift, postoperative seizures and the presence of anticoagulation were analyzed for their association with ABO blood type. Results Patient’s with blood type O were found to have a lower midline shift (p<0.01) and significantly less seizures (OR: 0.43; p<0.05) compared to non-O patients. Furthermore, patients with blood type A had the a significantly higher midline shift (p<0.05) and a significantly increased risk for postoperative seizures (OR: 4.01; p<0.001). There was no difference in ABO blood type distribution between acute subdural hematoma patients and the average population. Conclusion The ABO blood type has significant influence on acute subdural hematoma sequelae. Patient’s with blood type O benefit in their clinical course after acute subdural hematoma whereas blood type A patients are at highest risk for increased midline shift and postoperative seizures. Further studies elucidating the biological mechanisms of blood type depended hemostaseology and its role in acute subdural hematoma are required for the development of an appropriate intervention.


Journal of Neuro-oncology | 2018

Dexamethasone-induced leukocytosis is associated with poor survival in newly diagnosed glioblastoma

Daniel Dubinski; Sae-Yeon Won; Florian Gessler; Johanna Quick-Weller; Bedjan Behmanesh; Simon Bernatz; Marie-Therese Forster; Kea Franz; Karl-Heinz Plate; Volker Seifert; Patrick N. Harter; Christian Senft

Background Subdural hematoma (SDH) is a common disease associated with high morbidity, which is becoming more prominent due to the increasing incidence. Decision for a surgical evacuation is made depending on the clinical appearance and the volume of SDH, wherefore it is important to have a simple ‘bedside’ method to measure and compare the volume of SDH. Objective The aim of the study was to verify the accuracy of the simplified ABC/2 volumetric formula to determine a valuable tool for the clinical practice. Methods Preoperative CT-scans of 83 patients with SDHs were used for the computer-assisted volumetric measurement via BrainLab® as well as the ABC/2 volumetric measurement. A = largest length (anterior to posterior) of the SDH; B = maximum width (lateral to midline) 90° to A; C = maximum height (coronal plane or multiplication of slices) of the hematoma. These measurements were performed by two independent clinicians in a blinded fashion. Both volumes were compared by linear regression analysis of Pearson and Bland-Altman regression analysis. Results Among 100 SDHs, 53% were under an 47% were over 100cm3 showing a well distribution of the hematoma sizes. There was an excellent correlation between computer-assisted volumetric measurement and ABC/2 (R2 = 0.947, p<0.0001) and no undesirable deviation and trend were detected (p = 0.101; p = 0.777). A 95% tolerance region of the ratios of both methods was [0.805–1.201]. Conclusion The ABC/2 method is a simple and fast bedside formula for the measurement of SDH volume in a timely manner without limited access through simple adaption, which may replace the computer-assisted volumetric measurement in the clinical and research area. Reason for the good accuracy seems to be the spherical form of SDH, which has a similarity to a half ellipsoid.


Clinical Neurology and Neurosurgery | 2018

Prognostic risk factors for postoperative hemorrhage in stereotactic biopsies of lesions in the basal ganglia

Dana Farahmand; Fee Keil; Marie Göhring; Nazife Dinc; Volker Seifert; Gerhard Marquardt; Sae-Yeon Won; Johanna Quick-Weller

Despite its well-characterized side effects, dexamethasone is widely used in the pre-, peri- and postoperative neurosurgical setting due to its effective relief of tumor-induced symptoms through the reduction of tumor-associated edema. However, some patients show laboratory-defined dexamethasone induced elevation of white blood cell count, and its impact on glioblastoma progression is unknown. We retrospectively analyzed 113 patients with newly diagnosed glioblastoma to describe the incidence, risk factors and clinical features of dexamethasone-induced leukocytosis in primary glioblastoma patients. We further conducted an immunohistochemical analysis of the granulocyte and lymphocyte tumor-infiltration in the available corresponding histological sections. Patient age was identified to be a risk factor for the development of dexamethasone-induced leukocytosis (p < 0.05). The presence of dexamethasone-induced leukocytosis decreased overall survival (HR 2.25 95% CI [1.15–4.38]; p < 0.001) and progression-free survival (HR 2.23 95% CI [1.09–4.59]; p < 0.01). Furthermore, patients with dexamethasone-induced leukocytosis had significantly reduced CD15 + granulocytic- (p < 0.05) and CD3 + lymphocytic tumour infiltration (p < 0.05). We identified a subgroup of glioblastoma patients that are at particularly high risk for poor outcome upon dexamethasone treatment. Therefore, restrictive dosage or other edema reducing substances should be considered in patients with dexamethasone-induced leukocytosis.


Acta Neurochirurgica | 2018

Influence of ABO blood type on the outcome after non-aneurysmal subarachnoid hemorrhage

Daniel Dubinski; Sae-Yeon Won; Bedjan Behmanesh; Sepide Kashefiolasl; Christof Geisen; Volker Seifert; Christian Senft; Juergen Konczalla

OBJECTIVE The risk of hemorrhages after stereotactic biopsy is known to be low. Nevertheless hemorrhages in eloquent areas result in neurological deficit for the patients. Since the basal ganglia resemble a particularily high vascularized and eloquent location, which is often the source of hypertensive hemorrhages, we aimed to analyse possible risk factors for hemorrhage after stereotactic biopsy in this region. PATIENTS AND METHODS We performed a retrospective analysis including patients who underwent stereotactic biopsies of lesions in the basal ganglia between January 2012 and January 2017. 63 patients were included in this study. We accessed age, gender, histopathological diagnosis, hypertension, blood pressure intraoperative, anticoagulative medication and postoperative hemorrhage. RESULTS Fishers exact test revealed no significant p-values concerning anticoagulative therapy, gender, smoking and hypertension concerning postoperative hemorrhage. Wilcoxon-Mann-Whitney-Test showed no significant correlation for systolic blood pressure intraoperative, number of tissue samples and age with hemorrhage. A trend for lymphoma in correlation with postoperative hemorrhage was in patients with Lymphoma (Wilcoxon-Mann-Whitney Test). CONCLUSION Stereotactic biopsies even in eloquent areas as the basal ganglia are a safe procedure even if patients suffer under hypertension or are smoker. None of the here examined risk factors showed a significant correlation with postoperative hemorrhage. Accessing tumor tissue for histopathological diagnosis is mandatory for adequate therapy.


Seizure-european Journal of Epilepsy | 2017

A systematic review of epileptic seizures in adults with subdural haematomas

Sae-Yeon Won; Juergen Konczalla; Daniel Dubinski; Adriano Cattani; Colleen Cuca; Volker Seifert; Felix Rosenow; Adam Strzelczyk; Thomas M. Freiman

BackgroundIn patients with non-aneurysmal subarachnoid hemorrhage (NA-SAH), the etiology is unknown and the bleeding source remains unidentified. However, the ABO blood type system has a profound role in patient’s hemostasis and thrombosis. To date, the aspect of ABO blood type in incidence, clinical course, and outcome after NA-SAH has not been investigated.MethodsIn this retrospective analysis, 81 patients with non-traumatic and non-aneurysmal subarachnoid hemorrhage treated between 2010 and 2014 at the author’s institution were included. WFNS admission status, cerebral vasospasm, delayed infarction, ventriculoperitoneal shunt necessity, the Fisher grade, and the modified Rankin Scale were analyzed for their association with ABO blood type. Four hundred seventy patients with aneurysmal subarachnoid hemorrhage served as a control group.ResultsThe AB blood type is more frequent in NA-SAH compared to aneurysmal patients and the German population (OR 2.45, p ≤ 0.05). Furthermore, NA-SAH with AB blood type showed a similar sequelae compared to aneurysmal patients in terms of shunt necessity (OR 2.00, p ≥ 0.05), cerebral vasospasm (OR 1.66, p ≥ 0.05), and delayed infarctions (OR 1.07, p ≥ 0.05).ConclusionThe clinical course of NA-SAH AB blood type patients shows similar severity as of aneurysmal subarachnoid hemorrhage. Therefore, patients with AB blood type should be under intensified observation.

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Volker Seifert

Goethe University Frankfurt

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Daniel Dubinski

Goethe University Frankfurt

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Juergen Konczalla

Goethe University Frankfurt

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Christian Senft

Goethe University Frankfurt

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Markus Bruder

Goethe University Frankfurt

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Nazife Dinc

Goethe University Frankfurt

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Nina Brawanski

Goethe University Frankfurt

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Bedjan Behmanesh

Goethe University Frankfurt

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Eva Herrmann

Goethe University Frankfurt

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