Added Predictive Values of Proton Density Magnetic Resonance Imaging on Posterior Communicating Artery Aneurysms and Surrounding Soft Tissues with Simple Classification

Objective@#: Deciphering the anatomy of posterior communicating artery (PCoA) aneurysms in relation to surrounding structures is essential to determine adjuvant surgical procedures. However, it is difficult to predict surgical structures through preoperative imaging studies. We aimed to present anatomical structures using preoperative high-resolution three-dimensional proton densityweighted turbo spin-echo magnetic resonance (PDMR) imaging with simple classification. @*Methods@#: From January 2020 to April 2022, 30 patients underwent PDMR before microsurgical clipping for unruptured PCoA aneurysms in a single tertiary institute. We retrospectively reviewed the radiographic images and operative data of these patients. The structural relationship described by PDMR and intraoperative findings were compared. Subsequently, we classified aneurysms into two groups and analyzed the rate of adjuvant surgical procedures and contact with the surrounding structures. @*Results@#: Correlations between preoperative PDMR predictions and actual intraoperative findings for PCoA aneurysm contact to the oculomotor nerve, temporal uncus, and anterior petroclinoid fold (APCF) reported a diagnostic accuracy of 0.90, 0.87, and 0.90, respectively. In 12 patients (40.0%), an aneurysm dome was located on the plane of the oculomotor triangle and was classified as the infratentorial type. Compared to the supratentorial type PCoA aneurysm, adjuvant procedures were required more frequently (66.7% vs. 22.2%, p=0.024) for infratentorial type PCoA aneurysm clipping. @*Conclusion@#: Preoperative PCoA aneurysm categorization using PDMR can be helpful for predicting surgical complexity and planning of microsurgical clipping.

Retreatment of a recurrent giant aneurysm of the internal carotid artery after treatment with a flow-diverting stent

Flow-diverting stents (FDSs) have proven advantageous for the treatment of large, fusiform, and dissecting aneurysms that are otherwise difficult to treat. Retreatment strategies for recurrent large or giant aneurysms after FDSs are limited to overlapping implantation of an additional FDS or definitive occlusion of the parent vessel. We report a recurrent giant aneurysm that was initially treated with an FDS with coils and was successfully treated with an additional FDS. Visual symptoms due to the mass effect of the recurrent aneurysm were completely resolved, and follow-up digital subtraction angiography revealed complete obliteration of the aneurysm. Additional FDS implantation for the retreatment of incompletely occluded aneurysms after the initial FDS treatment may be feasible and safe. Further studies are required to validate these results.

Alterations of vital signs as prognostic factors after intraprocedural rupture of intracranial aneurysms during endovascular treatment

Objective@#To report our experience with intraprocedural rupture (IPR) of intracranial aneurysms during endovascular treatment and evaluate alterations in vital signs as independent prognostic factors to predict the outcomes of IPR. @*Methods@#Between January 2008 and August 2021, 34 patients (8 ruptured and 26 unruptured) were confirmed to have IPR based on our dataset with 3178 endovascular coiling procedures. The patients who underwent additional surgeries related to IPR were classified as the OP group (n=9), while those who did not receive additional surgeries were classified as the non-OP group (n=25). Vital signs were recorded during the procedure by anesthesiologists and analyzed. @*Results@#Of the 34 patients included in this study, eight initially presented with subarachnoid hemorrhage due to a ruptured aneurysm. The clinical outcomes at discharge were significantly different between the two groups (p=0.046). In the OP group, five patients showed favorable outcomes at discharge, while four showed unfavorable outcomes. In the non-OP group, 23 patients showed favorable outcomes at discharge while two patients showed unfavorable outcomes. Maximal (MAX) systolic blood pressure (SBP) (odds ratio [OR] 1.520, 95% confidence interval [CI] 1.084-2.110; p=0.037) and higher differential value MAX-median blood pressure (MBP) (OR 1.322, 95% CI 1.029-1.607; p=0.044) remained independent risk factors for poor prognosis after IPR on multivariate logistic regression analysis. @*Conclusions@#The MAX SBP and the difference between the maximal and baseline values of MBP are key factors in predicting the prognosis of patients after IPR, as well as providing useful information for predicting the outcome. Further research is required to confirm the relationship between naive pressure and prognosis.

Stent-assisted coiling of a ruptured basilar artery perforator aneurysm: A case report

Basilar artery (BA) perforator aneurysms are exceedingly rare causes of subarachnoid hemorrhage. Therefore, the natural history and optimal treatment have not been established, and surgical, endovascular, and conservative management have been used. However, there is no consensus on the optimal treatment strategy. Herein, we report the case of a 52-year-old man presenting with a ruptured BA perforator aneurysm. First, we deployed an Enterprise stent from the left P1 segment to the BA because the microcatheter could not enter the aneurysm. Then, we deployed a helical coil on the orifice of the BA perforator. Finally, we deployed another Enterprise stent, sandwiching the helical coil between the two Enterprise stents. The aneurysm was completely obliterated without recurrence on the follow-up angiography. Our technique of sandwiching the small helical coil between two Enterprise stents might help other surgeons by offering another feasible treatment option for ruptured BA perforator aneurysms.

Y-stent-assisted coiling with Neuroform Atlas stents for wide-necked intracranial bifurcation aneurysms: A preliminary report

Objective@#To report our experience on Neuroform Atlas Y-stenting for coiling of unruptured wide-neck bifurcation aneurysms. @*Methods@#From March 2018 to January 2021, we treated 473 aneurysms in 436 patients with coil embolization, of which 15 cases with wide-necked bifurcation aneurysms were treated by Y-stent-assisted coiling with two Neuroform Atlas stents. We retrospectively reviewed the characteristics of patients and aneurysms, procedure-related complications, radiographic results, and clinical outcomes. @*Results@#All 15 cases using Neuroform Atlas Y-stenting were successful. Patients included 6 men and 9 women with a mean age ± standard deviation of 56.4±6.6 years. The mean dome and neck sizes were 6.4±3.1 mm and 4.7±1.8 mm, respectively. Immediate post-procedural angiograms showed complete occlusion in 46.7%, neck remnant in 13.3%, and incomplete occlusion in 40% of cases. No treatment-related morbidity or mortality occurred in any patients. All patients had good clinical outcomes (Glasgow Outcome Score 5) at both discharge and during a mean 12.3-month (range 1-28 months) follow-up. All aneurysms showed improved or stable occlusion on follow-up imaging. Further, the latest follow-up angiography showed complete occlusion in 73.3%, neck remnant in 6.7%, and incomplete occlusion in 20%. @*Conclusions@#Y-stent-assisted coiling with Neuroform Atlas stents might be a feasible and safe option for wide-necked bifurcation aneurysms.

Role of Transarterial Embolization in the Treatment of Life-Threatening Hemorrhage in Patients With Maxillofacial Injury / 대한신경손상학회지

Life-threatening hemorrhage following maxillofacial injury (MFI) is rare but can be fatal. Conventional measures for hemostasis including nasal packing, balloon tamponade, and surgical ligation of bleeding points may not be effective or efficient in patients at risk of hypovolemic shock. Advantages of transarterial embolization (TAE) include rapid identification of the bleeding focus and its access, direct obstruction of the culprit vessels, ability to control multiple bleeding sites, and no requirement of general anesthesia. The internal maxillary artery is the most frequently targeted vessel for embolization. Several studies have demonstrated that TAE was technically successful at rates between 79.4% and 100% and was associated with good clinical outcomes. However, major complications such as tongue necrosis or facial nerve palsy have rarely been reported (0%–7%), probably because of rich collaterals in the maxillofacial region, and failure to diagnose complications in patients who are severely disabled or died. Traditionally, Gelfoam and coils have been widely used as embolic materials. Polyvinyl alcohol particles and n-butyl-cyanoacrylate are also favored, and newer embolic materials, such as Onyx or precipitating hydrophobic injectable liquid, are available for use. Operators should be familiar with the distinctive characteristics of each embolic material. Early treatment with TAE for intractable hemorrhage may improve outcomes in patients with MFI, and further studies are necessary to develop a treatment algorithm to define when to initiate TAE in cases of severe oronasal hemorrhage following MFI.

A Single Flow Re-direction Endoluminal Device for the Treatment of Large and Giant Anterior Circulation Intracranial Aneurysms

Purpose@#The purpose of this study was to report the author’s experiences in treating large (10–25 mm) and giant (>25 mm) intracranial aneurysms (IAs) using a single Flow Re-direction Endoluminal Device (FRED) without assistant coiling, with a focus on procedure-related complications. @*Materials and Methods@#A total of 33 patients who were treated with FRED between January 2018 and July 2020 were retrospectively reviewed. The timing of procedure-related complications was chronologically categorized as acute (within 7 days), subacute (8 to 21 days), and delayed (after 21 days) periods. Follow-up angiography was performed at 2 to 27 months (mean 9.7 months), and clinical follow-up was performed at 1 to 31 months (mean 14.1 months) in all patients. @*Results@#Six (18.2%) patients experienced procedure-related complications, including 2 (6.1%) in acute period, 1 (3.0%) in subacute period, and 3 (9.1%) in delayed period. Thromboembolic complications occurred in 5 (15.2%) patients and hemorrhagic complications in 1 (3.0%). Permanent morbidity and mortality rates were 3.0% each. Non-internal carotid artery (ICA) location of IAs (odds ratio 6.532; 95% confidence interval, 1.335–17.816; p=0.034) was the only independent risk factor for procedure-related complications on multivariate logistic regression analysis. @*Conclusion@#The procedure-related complication rate was 18.2% in this study. Procedure-related complications might increase when treating large and giant IAs located on a non-ICA, especially on the middle cerebral artery. Therefore, it may be suggested that neurointerventionists and endovascular neurosurgeons should pay attention to the location of IAs when treating large and giant IAs with a single FRED.

Delays in Intracerebral Hemorrhage Management Is Associated with Hematoma Expansion and Worse Outcomes: Changes in COVID-19 Era

Purpose@#The coronavirus disease 2019 (COVID-19) pandemic disrupted the emergency medical care system worldwide. We analyzed the changes in the management of intracerebral hemorrhage (ICH) and compared the pre-COVID-19 and COVID-19 eras. @*Materials and Methods@#From March to October of the COVID-19 era (2020), 83 consecutive patients with ICH were admitted to four comprehensive stroke centers. We retrospectively reviewed the data of patients and compared the treatment workflow metrics, treatment modalities, and clinical outcomes with the patients admitted during the same period of pre-COVID-19 era (2017–2019). @*Results@#Three hundred thirty-eight patients (83 in COVID-19 era and 255 in pre-COVID-19 era) were included in this study. Symptom onset/detection-to-door time [COVID-19; 56.0 min (34.0–106.0), pre-COVID-19; 40.0 min (27.0–98.0), p=0.016] and median door to-intensive treatment time differed between the two groups [COVID-19; 349.0 min (177.0–560.0), pre-COVID-19; 184.0 min (134.0–271.0), p<0.001]. Hematoma expansion was detected more significantly in the COVID-19 era (39.8% vs. 22.1%, p=0.002). At 3-month follow-up, clinical outcomes of patients were worse in the COVID-19 era (Good modified Rankin Scale; 33.7% in COVID-19, 46.7% in pre-COVID-19, p=0.039). @*Conclusion@#During the COVID-19 era, delays in management of ICH was associated with hematoma expansion and worse outcomes.

Comparative Analysis of Feasibility of the Retrograde Suction Decompression Technique for Microsurgical Treatment of Large and Giant Internal Carotid Artery Aneurysms

Objective@#: Retrograde suction decompression (RSD) is an adjuvant technique used for the microsurgical treatment of large and giant internal carotid artery (ICA) aneurysms. In this study, we analyzed the efficacy and safety of the RSD technique for the treatment of large and giant ICA aneurysms relative to other conventional microsurgical techniques. @*Methods@#: The aneurysms were classified into two groups depending on whether the RSD method was used (21 in the RSD group vs. 43 in the non-RSD group). Baseline characteristics, details of the surgical procedure, angiographic outcomes, clinical outcomes, and procedure-related complications of each group were reviewed retrospectively. @*Results@#: There was no significant difference in the rates of complete neck-clipping between the RSD (57.1%) and non-RSD (67.4%) groups. Similarly, there was no difference in the rates of good clinical outcomes (modified Rankin Scale score, 0–2) between the RSD (85.7%) and non-RSD (81.4%) groups. Considering the initial functional status, 19 of 21 (90.5%) patients in the RSD group and 35 of 43 (81.4%) patients in the non-RSD group showed an improvement or no change in functional status, which did not reach statistical significance. @*Conclusion@#: In this study, the microsurgical treatment of large and giant intracranial ICA aneurysms using the RSD technique obtained competitive angiographic and clinical outcomes without increasing the risk of procedure-related complications. The RSD technique might be a useful technical option for the microsurgical treatment of large and giant intracranial ICA aneurysms.

Delays in Intracerebral Hemorrhage Management Is Associated with Hematoma Expansion and Worse Outcomes: Changes in COVID-19 Era

Purpose@#The coronavirus disease 2019 (COVID-19) pandemic disrupted the emergency medical care system worldwide. We analyzed the changes in the management of intracerebral hemorrhage (ICH) and compared the pre-COVID-19 and COVID-19 eras. @*Materials and Methods@#From March to October of the COVID-19 era (2020), 83 consecutive patients with ICH were admitted to four comprehensive stroke centers. We retrospectively reviewed the data of patients and compared the treatment workflow metrics, treatment modalities, and clinical outcomes with the patients admitted during the same period of pre-COVID-19 era (2017–2019). @*Results@#Three hundred thirty-eight patients (83 in COVID-19 era and 255 in pre-COVID-19 era) were included in this study. Symptom onset/detection-to-door time [COVID-19; 56.0 min (34.0–106.0), pre-COVID-19; 40.0 min (27.0–98.0), p=0.016] and median door to-intensive treatment time differed between the two groups [COVID-19; 349.0 min (177.0–560.0), pre-COVID-19; 184.0 min (134.0–271.0), p<0.001]. Hematoma expansion was detected more significantly in the COVID-19 era (39.8% vs. 22.1%, p=0.002). At 3-month follow-up, clinical outcomes of patients were worse in the COVID-19 era (Good modified Rankin Scale; 33.7% in COVID-19, 46.7% in pre-COVID-19, p=0.039). @*Conclusion@#During the COVID-19 era, delays in management of ICH was associated with hematoma expansion and worse outcomes.

Comparative Analysis of Feasibility of the Retrograde Suction Decompression Technique for Microsurgical Treatment of Large and Giant Internal Carotid Artery Aneurysms

Objective@#: Retrograde suction decompression (RSD) is an adjuvant technique used for the microsurgical treatment of large and giant internal carotid artery (ICA) aneurysms. In this study, we analyzed the efficacy and safety of the RSD technique for the treatment of large and giant ICA aneurysms relative to other conventional microsurgical techniques. @*Methods@#: The aneurysms were classified into two groups depending on whether the RSD method was used (21 in the RSD group vs. 43 in the non-RSD group). Baseline characteristics, details of the surgical procedure, angiographic outcomes, clinical outcomes, and procedure-related complications of each group were reviewed retrospectively. @*Results@#: There was no significant difference in the rates of complete neck-clipping between the RSD (57.1%) and non-RSD (67.4%) groups. Similarly, there was no difference in the rates of good clinical outcomes (modified Rankin Scale score, 0–2) between the RSD (85.7%) and non-RSD (81.4%) groups. Considering the initial functional status, 19 of 21 (90.5%) patients in the RSD group and 35 of 43 (81.4%) patients in the non-RSD group showed an improvement or no change in functional status, which did not reach statistical significance. @*Conclusion@#: In this study, the microsurgical treatment of large and giant intracranial ICA aneurysms using the RSD technique obtained competitive angiographic and clinical outcomes without increasing the risk of procedure-related complications. The RSD technique might be a useful technical option for the microsurgical treatment of large and giant intracranial ICA aneurysms.

Outcomes of Stent-Assisted Coiling Using the Neuroform Atlas Stent in Unruptured Wide-Necked Intracranial Aneurysms

Objective@#: Although stent-assisted coiling (SAC) has been reported to be safe and effective in treating wide-necked aneurysms, the technique has procedure-related complications. Thus, we reported our experiences of SAC using the Neuroform Atlas stent in treating wide-necked aneurysms and evaluated the incidence of and risk factors for procedure-related complications. @*Methods@#: From March 2018 to August 2019, we treated 130 unruptured wide-necked aneurysms in 123 patients with Neuroform Atlas stents. Angiographic results and clinical outcomes were reviewed retrospectively. Clinical and angiographic follow-up were performed in all cases (mean, 12.4 months) after the procedure. @*Results@#: There were eight cases (6.2%) of procedure-related complications (two dissections, five thromboembolisms, and one hemorrhage) and two (1.5%) of delayed complications (one ischemia and one hemorrhage). There was one case (0.8%) of failure of stent deployment and one (0.8%) of suboptimal positioning of the stent. Follow-up angiography showed complete obliteration in 103 (79.2%), residual neck in 16 (12.3%), and residual aneurysm in 11 cases (8.5%). Aneurysm locations in the middle cerebral artery (odds ratio [OR], 2.211; p=0.046) and the anterior communicating artery (OR, 2.850; p=0.039) were associated with procedurerelated complications on univariate analysis. However, no independent risk factor for procedure-related complications was noted in multivariate analysis. @*Conclusion@#: The Neuroform Atlas showed a high rate of technical success. Good clinical and radiographic outcomes in early follow-up suggests that the device is feasible and safe. SAC of aneurysms on the middle cerebral artery or anterior communicating artery may require more attention to prevent possible procedure-related complications.

Wingspan Stenting for Symptomatic Severe In-Stent Stenosis of a Closed-Cell Stent after Stent-Assisted Coiling of a Ruptured Intracranial Aneurysm

We report the 3-year follow-up result of Wingspan intracranial stenting for symptomatic severe in-stent stenosis after stent-assisted coiling (SAC) for a ruptured left distal internal carotid artery (ICA) aneurysm. A middle-aged male patient visited our hospital for in-stent stenosis of a stent that was placed to treat a ruptured ICA aneurysm. Routine follow-up cerebral angiography, 1 year after SAC, showed in-stent stenosis around the distal markers of the inserted stent at the left M1 proximal segment. Six months later, he developed right dysesthesia. We performed intracranial stenting with Wingspan stent for the in-stent stenosis. Follow-up digital subtraction angiography performed 1 year after the Wingspan stenting showed good patency of the ICA and middle cerebral artery flow without evidence of restenosis. At 3-year follow-up, magnetic resonance angiography showed sufficient middle cerebral artery flow although the stenting segment could not be visualized clearly. Wingspan stenting might be a feasible option in patients with iatrogenic intracranial stenosis resulting from in-stent stenosis who experience the progression of intracranial stenosis with manifestation of neurological symptoms despite dual anti-platelet therapy.

Delayed Remote Intracerebral Hemorrhage after Wingspan Stenting for Internal Carotid Artery Stenosis Following the On-Label Usage Guidelines

Remote intracerebral hemorrhage (ICH) is defined as an ICH that occurs at a distant site from the treated lesion and is a considerable post-neurointerventional complication. Because such a life-threatening complication should not be neglected, we report our experience with delayed remote ICH in a patient with symptomatic intracranial atherosclerotic stenosis (ICAS) treated by Wingspan stenting following on-label usage guidelines. A middle-aged person suffered a lobar-type subcortical hemorrhage on the left temporal lobe 22 days after Wingspan stenting in the left internal carotid artery. The present case seemed to correspond with a previous report in which remote ICH tended to occur as an ipsilateral lobar-type hemorrhage in patients with unruptured intracranial aneurysm on the internal carotid artery undergoing treatment with stents or flow diverters. Delayed remote ICH should be considered as a potential risk of using a Wingspan stent covering the carotid siphon for ICAS.

Clinical Features and Outcomes of Intracranial Aneurysm Associated with Moyamoya Disease

Background@#and Purpose: Moyamoya disease (MMD) is a rare form of intracranial stenoocclusive disease that can be associated with intracranial aneurysms. We evaluated the clinical features and outcomes of MMD-associated aneurysms while focusing on their locations. @*Methods@#Between January 1998 and December 2018 there were 1,302 adult and pediatric patients diagnosed as MMD at a single institution. These patients included 38 with 44 MMD-associated aneurysms. The MMD-associated aneurysms were classified into two groups based on their locations: major-artery aneurysms and non-major-artery aneurysms. The clinical and radiological data for patients with MMD-associated aneurysms were reviewed retrospectively. @*Results@#The 44 MMD-associated aneurysms comprised 28 in major arteries and 16 in nonmajor arteries. All of the major-artery aneurysms were initially unruptured lesions, and follow-up angiography showed that 23 (82.1%) had an improved or stable status and 5 (17.9%) had a worse status. The non-major-artery aneurysms comprised 10 ruptured and 6 unruptured lesions, and follow-up angiography showed that 11 (68.8%) had improved or were stable and 5 (31.2%) had worsened. At the latest follow-up, there were four cases of unfavorable outcome: two initial hemorrhagic insults, one treatment-related morbidity, and one repeatedhemorrhage case. @*Conclusions@#MMD-associated aneurysms occurred in 3.3% of the MMD cohort in this study, of which 63.6% were major-artery aneurysms and 36.4% were non-major-artery aneurysms. The major-artery group included 17.9% that became angiographically worse, while 31.2% were growing or hemorrhaging in the non-major-artery group.

A Newly-Developed Flow Diverter (FloWise) for Internal Carotid Artery Aneurysm: Results of a Pilot Clinical Study

OBJECTIVE: We report the results of a pilot clinical study that evaluated the safety and efficacy of a newly-developed, retrievable flow diverter (FloWise; Taewoong Medical) for the treatment of internal carotid artery (ICA) aneurysm. MATERIALS AND METHODS: A total of 10 patients were enrolled. Inclusion criteria were 1) unruptured aneurysm with a dome size of ≥ 8 mm and a neck size of ≥ 4 mm at the ICA, or 2) two or more unruptured aneurysms of any size able to be spanned by a single FloWise at the ICA. Co-primary effectiveness end points were technical success of FloWise placement, and a 50% or greater decrease in aneurysm volume at the 6-month follow-up angiogram. The primary safety end point was the new development of neurological deficits persisting for more than 1-month post-treatment. RESULTS: Ten patients harboring 14 ICA aneurysms (median diameter, 9.4 mm; range, 2.3–31.0 mm) were enrolled between January 2016 and July 2017. FloWise placement was successful in all patients. There were no newly-developed neurological deficits during the 6-month clinical follow-up period. One patient did not receive follow-up imaging due to pregnancy. Nine patients with 12 aneurysms received a 6-month angiographic follow-up. Ten aneurysms (83.3%) showed decreases in volume greater than 50% (mean volume decrease, 82.8 ± 32.9%), of which 8 (66.7%, 95% confidence interval, 35.4–98.0%) showed complete occlusion. One patient was retreated due to mass symptom aggravation. CONCLUSIONS: In this pilot study, FloWise appeared to be safe and effective for ICA aneurysm treatment. A prospective multicenter study to validate the effectiveness and safety of FloWise would be worthwhile.

Symptomatic Sinus Pericranii with Adult Onset Headache: A Case Report with Pathologic Perspective

Sinus pericranii (SP) is a rare vascular anomaly of the scalp that consists of an abnormal pericranial venous channel connected to adjacent dural venous sinuses. Most SP are asymptomatic and are found in the pediatric age group. We aim to report a case of symptomatic SP in adult and describe the clinical, radiological, and pathohistological findings to help understand and differentiate this lesion from other scalp lesions. A 40-year-old man with a scalp mass was admitted to our hospital complaining of headache. The lesion enlarged when the patient was in a recumbent position or during Valsalva maneuver. The radiologic imaging suggested its diagnosis as an accessory type of SP with bone erosion. Surgical resection and cranioplasty were successfully performed, and the related headache also gradually subsided. At the 3-year follow-up, there was no recurrence on magnetic resonance imaging.

External Ventricular Drainage before Endovascular Treatment in Patients with Aneurysmal Subarachnoid Hemorrhage in Acute Period: Its Relation to Hemorrhagic Complications / 신경중재치료의학

PURPOSE: The purpose of this study was to report the authors’ experience with external ventricular drainage (EVD) before endovascular treatment (EVT) in patients with acute aneurysmal subarachnoid hemorrhage (aSAH) and to investigate its relation to hemorrhagic complications. MATERIALS AND METHODS: Between March 2010 and December 2017, a total of 122 patients were recruited who had an aSAH, underwent EVT to secure the ruptured aneurysm, and had EVD performed within 72 hours of rupture. The pre-embo EVD group (n=67) comprised patients who underwent EVD before EVT, and the post-embo EVD group (n=55) comprised those who underwent EVD after EVT. RESULTS: Overall, EVD-related hemorrhage occurred in 18 patients (14.8%): six (8.9%) in the pre-embo EVD group and 12 (21.8%) in the post-embo EVD group (P=0.065). No rebleeding occurred between EVD and EVT in the pre-embo EVD group. Clinical outcomes at discharge did not differ significantly between groups (P=0.384). At discharge, the final modified Rankin Scale score in patients who experienced pre-embo rebleeding was better in the pre-embo EVD group than in the post-embo EVD group (P=0.041). Current use of an antiplatelet agent or anticoagulant on admission (odds ratio [OR], 2.928; 95% confidence interval [CI], 1.234–7.439; P=0.042) and stent use (OR, 2.430; 95% CI, 1.524–7.613; P=0.047) remained independent risk factors for EVD-related hemorrhagic complications. CONCLUSION: EVD before EVT in patients with aSAH in acute period did not increase the rate of rebleeding as well as EVD-related hemorrhagic complications. Thus, performing EVD before EVT may be beneficial by normalizing increased intracranial pressure. Especially in patients with rebleeding before the ruptured aneurysm is secured, pre-embo EVD may improve clinical outcomes at discharge.

Coil-Protected Technique for Liquid Embolization in Neurovascular Malformations

OBJECTIVE: To evaluate the safety and efficacy of the coil-protected technique for liquid embolization in neurovascular malformations. MATERIALS AND METHODS: Twenty-two patients who underwent coil-protected liquid embolization for symptomatic cranial (n = 13) and spinal (n = 9) arteriovenous fistula (AVF) or arteriovenous malformations (AVMs) were identified. A total of 36 target feeder vessels were embolized with N-butyl cyanoacrylate and/or Onyx (Medtronic). This technique was used to promote delivery of a sufficient amount of liquid embolic agent into the target shunt or nidus in cases where tortuous feeding arteries preclude a microcatheter wedging techniqu and/or to prevent reflux of the liquid embolic agent in cases with a short safety margin. The procedure was considered technically successful if the target lesion was sufficiently filled with liquid embolic agent without unintentional reflux. Angiographic and clinical outcomes were retrospectively evaluated. RESULTS: Technical success was achieved for all 36 target feeders. Post-embolization angiographies revealed complete occlusion in 16 patients and near-complete and partial occlusion in three patients each. There were no treatment-related complications. Of the six patients who showed near-complete or partial occlusion, five received additional treatments: two received stereotactic radiosurgery for cerebral AVM, two underwent surgical removal of cerebral AVM, and one underwent additional embolization by direct puncture for a mandibular AVM. Finally, all patients showed complete (n = 19) or near-complete (n = 3) occlusion of the target AVF or AVM on follow-up angiographies. The presenting neurological symptoms improved completely in 15 patients (68.2%) and partially in seven patients (31.8%). CONCLUSION: The coil-protected technique is a safe and effective method for liquid embolization, especially in patients with various neurovascular shunts or malformations who could not be successfully treated with conventional techniques.

Korean Clinical Practice Guidelines for Aneurysmal Subarachnoid Hemorrhage

Despite advancements in treating ruptured cerebral aneurysms, an aneurysmal subarachnoid hemorrhage (aSAH) is still a grave cerebrovascular disease associated with a high rate of morbidity and mortality. Based on the literature published to date, worldwide academic and governmental committees have developed clinical practice guidelines (CPGs) to propose standards for disease management in order to achieve the best treatment outcomes for aSAHs. In 2013, the Korean Society of Cerebrovascular Surgeons issued a Korean version of the CPGs for aSAHs. The group researched all articles and major foreign CPGs published in English until December 2015 using several search engines. Based on these articles, levels of evidence and grades of recommendations were determined by our society as well as by other related Quality Control Committees from neurointervention, neurology and rehabilitation medicine. The Korean version of the CPGs for aSAHs includes risk factors, diagnosis, initial management, medical and surgical management to prevent rebleeding, management of delayed cerebral ischemia and vasospasm, treatment of hydrocephalus, treatment of medical complications and early rehabilitation. The CPGs are not the absolute standard but are the present reference as the evidence is still incomplete, each environment of clinical practice is different, and there is a high probability of variation in the current recommendations. The CPGs will be useful in the fields of clinical practice and research.