Pipeline Embolization Device for Large/Giant or Fusiform Aneurysms: An Initial Multi-Center Experience in Korea / 신경중재치료의학

PURPOSE: The purpose of this study was to assess the safety and early outcomes of the Pipeline device for large/giant or fusiform aneurysms. MATERIALS AND METHODS: The Pipeline was implanted in a total of 45 patients (mean age, 58 years; M:F=10:35) with 47 large/giant or fusiform aneurysms. We retrospectively evaluated the characteristics of the treated aneurysms, the periprocedural events, morbidity and mortality, and the early outcomes after Pipeline implantation. RESULTS: The aneurysms were located in the internal carotid artery (ICA) cavernous segment (n=25), ICA intradural segment (n=11), vertebrobasilar trunk (n=8), and middle cerebral artery (n=3). Procedure-related events occurred in 18 cases, consisting of incomplete expansion (n=8), shortening-migration (n=5), transient occlusion of a jailed branch (n=3), and in-stent thrombosis (n=2). Treatment-related morbidity occurred in two patients, but without mortality. Both patients had modified Rankin scale (mRS) scores of 2, but had an improved mRS score of 0 at 1-month follow-up. Of the 19 patients presenting with mass effect, 16 improved but three showed no changes in their presenting symptoms. All patients had excellent outcomes (mRS, 0 or 1) during the follow-up period (median, 6 months; range, 2-30 months). Vascular imaging follow-up (n=31, 65.9%; median, 3 months, range, 1-25 months) showed complete or near occlusion of the aneurysm in 24 patients (77.4%) and decreased sac size in seven patients (22.6%). CONCLUSION: In this initial multicenter study in Korea, the Pipeline seemed to be safe and effective for large/giant or fusiform aneurysms. However, a learning period may be required to alleviate device-related events.

Standards for Endovascular Neurosurgical Training and Certification of the Society of Korean Endovascular Neurosurgeons 2013

The need for standard endovascular neurosurgical (ENS) training programs and certification in Korea cannot be overlooked due to the increasing number of ENS specialists and the expanding ENS field. The Society of Korean Endovascular Neurosurgeons (SKEN) Certification Committee has prepared training programs and certification since 2010, and the first certificates were issued in 2013. A task force team (TFT) was organized in August 2010 to develop training programs and certification. TFT members researched programs and systems in other countries to develop a program that best suited Korea. After 2 years, a rough draft of the ENS training and certification regulations were prepared, and the standard training program title was decided. The SKEN Certification Committee made an official announcement about the certification program in March 2013. The final certification regulations comprised three major parts: certified endovascular neurosurgeons (EN), certified ENS institutions, and certified ENS training institutions. Applications have been evaluated and the results were announced in June 2013 as follows: 126 members received EN certification and 55 hospitals became ENS-certified institutions. The SKEN has established standard ENS training programs together with a certification system, and it is expected that they will advance the field of ENS to enhance public health and safety in Korea.

The Difference of Each Angiographic Finding After Multiple Stent According to Stent Type in Bilateral Vertebral Artery Dissection

We report a case of spontaneous bilateral intracranial vertebral artery dissecting aneurysms with subarachnoid hemorrhage. One dissecting lesion was treated with a coronary balloon-mounted stent (BMS) technique; however, due to differences in access route tortuosity, the other lesion was treated with a self-expandable stent (SES) technique. After 2 months, the angiographic outcome showed complete healing of the dissected segment on the side that was treated with BMS; in contrast, the dissection lesion appeared to be re-growing on the side that was treated with SES. Complete treatment of the aggravated lesion was achieved by additional deployment of BMSs. Therefore, we have provided a discussion of the possible reasons for this difference in outcome according to the stent type.

The Difference of Each Angiographic Finding After Multiple Stent According to Stent Type in Bilateral Vertebral Artery Dissection

We report a case of spontaneous bilateral intracranial vertebral artery dissecting aneurysms with subarachnoid hemorrhage. One dissecting lesion was treated with a coronary balloon-mounted stent (BMS) technique; however, due to differences in access route tortuosity, the other lesion was treated with a self-expandable stent (SES) technique. After 2 months, the angiographic outcome showed complete healing of the dissected segment on the side that was treated with BMS; in contrast, the dissection lesion appeared to be re-growing on the side that was treated with SES. Complete treatment of the aggravated lesion was achieved by additional deployment of BMSs. Therefore, we have provided a discussion of the possible reasons for this difference in outcome according to the stent type.

Endovascular Treatment of Blood Blister-Like Aneurysms Using Multiple Self-Expanding Stents

The surgical as well as endovascular treatment of blood-blister-like aneursysms (BBAs) is extremely difficult because of these pathological natures, such as small and the fragile necks. The optimal treatment of BBAs has remained uncertain. Stents are known to divert blood flow and induce thrombosis of intracranial aneurysms. We report 3 cases of successful obliteration of BBAs after multiple stents placement.

Changes in Bypass Flow during Temporary Occlusion of Unused Branch of Superficial Temporal Artery

OBJECTIVE: Some neurosurgeons intentionally ligate the branches of the superficial temporal artery (STA) that are not used in standard STA-to-middle cerebral artery (MCA) anastomosis for the purpose of improving the flow rate in the bypass graft. We investigated changes in bypass flow during temporary occlusion of such unused branches of the STA. METHODS: Bypass blood flow was measured by a quantitative microvascular ultrasonic flow probe before and after temporary occlusion of branches of the STA that were not used for anastomosis. We performed measurements on twelve subjects and statistically assessed changes in flow. We also examined all the patients with digital subtraction angiography in order to observe any post-operative changes in STA diameter. RESULTS: Initial STA flow ranged from 15 mL/min to 85 mL/min, and the flow did not change significantly during occlusion as compared with pre-occlusion flow. The occlusion time was extended by 30 minutes in all cases, but this did not contribute to any significant flow change. CONCLUSION: The amount of bypass flow in the STA seems to be influenced not by donor vessel status but by recipient vessel demand. Ligation of the unused STA branch after completion of anastomosis does not contribute to improvement in bypass flow immediately after surgery, and furthermore, carries some risk of skin necrosis. It is better to leave the unused branch of the STA intact for use in secondary operation and to prevent donor vessel occlusion.

Is Transradial Cerebral Angiography Feasible and Safe? A Single Center's Experience

OBJECTIVE: Although a transradial angiography is accepted as the gold standard for cardiovascular procedures, cerebral angiography has been performed via transfemoral approach in most institutions. The purpose of this study is to present our experience concerning the feasibility, efficacy, and safety of a transradial approach to cerebral angiography as an alternative to a transfemoral approach. METHODS: Between February 2007 and October 2009, a total of 1,240 cerebral angiographies were performed via a transradial approach in a single center. The right radial approach was used as an initial access route. The procedure continued only after the ulnar artery was proven to provide satisfactory collateral perfusion according to two tests (a modified Allen's test and forearm angiography). RESULTS: The procedural success rate was 94.8% with a mean duration of 28 minutes. All supra-aortic vessels were successfully catheterized with a success rate of 100%. The success rates of selective catheterization to the right vertebral artery, right internal carotid artery, left internal carotid artery, and left vertebral artery were 96.1%, 98.6%, 82.6% and 52.2%, respectively. The procedure was performed more than twice in 73 patients (5.9%), including up to 4 times in 2 patients. The radial artery occlusion was found in 4 patients (5.4%) on follow-up cerebral angiography, but no ischemic symptoms were observed in any of the cases. CONCLUSION: This study suggests that cerebral angiography using a transradial approach can be performed with minimal risk of morbidity. In particular, this procedure might be useful for follow-up angiographies and place less stress on patients.

Minimally Invasive and Tailored Surgical Approach to the Anterior Circulation Aneurysms / 대한뇌혈관외과학회지

OBJECTIVES: Supraorbital route through eyebrow incision, mini-pterional craniotomy, and midline interhemispheric route are most generally used methods for key hole surgery on anterior circulation aneurysm. Surgical route is determined according to aneurysm architecture and patient status. The approaching route can be selected according to the findings of 3-dimensional computed tomography (CT) angiography simulation. Prospective decision-making protocol, surgical technique of key hole surgery, and the results are presented in this paper. METHODS: 173 patients with anterior circulation aneurysms were treated by direct surgical neck clipping during last two years. Twenty patients of poor grade (Hunt-Hess grade IV,V) were treated by craniectomy with clipping. Decision making protocol was applied to 153 unruptured and good grade ruptured aneurysm patients. Simulation of key hole surgery was conducted by CT work station using conventional software InSpace (Siemens, Germany), and direction and shape of aneurysm was observed from the perspective of microsurgery. RESULTS: 113 ruptured and 40 unruptured aneurysms were secured through one of the three approaching routes. Supraorbital approach had been performed in 82 cases (unruptured 24, ruptured 58) while 64 cases were treated by mini-pterional craniotomy. Midline key hole surgery were carried out in seven distal anterior circulation aneurysms (DACA) using brain navigation system. After locating the aneurysm, supraorbital approach was applied to 46 cases involving anterior cerebral artery (ACA), 16 in internal carotid artery (ICA) and 20 in middle cerebral artery (MCA). Mini-pterional craniotomy was carried out in aneurysms located in ACA (9), ICA (18), and MCA (37). In most cases, the results of clipping were good. The average follow-up time was 16.7months (ranging 2 to 32months) and the results were cosmetically excellent. CONCLUSION: Simulating surgical approaches with 3-D CT angiography is a highly useful method for determining various surgical routes in anterior circulation aneurysm treatment. Therefore, minimally invasive and tailored surgical approaches are recommended since optimal route can be found through simulation. Thus, minimal invasive and tailored surgical approach is available through this method. These procedures have clear advantages; shorter surgical time and hospital stay, less operative trauma, reduced costs and less pain, and better cosmetic outcomes compared to standard craniotomy. Optimal surgical results are expected from minimally invasive and tailored surgical craniotomy.

The Expansion of Cervical Synovial Cyst after Trauma : A Case Report and Literature Review

We report a rare case that showed aggravation of neurological symptoms due to expansion of the synovial cyst at C7/T1 after several month of trauma and present the consideration of proper prevention and management. A 64-year old male was admitted by right arm weakness(GIV+) after a pedestrian traffic accident. According to computed tomography(CT) scan and electromyography(EMG), a brachial plexus injury was diagnosed and he was treated conservatively. After 7 months, he was re-admitted by the left side weakness(GIV-) with severe pain and magnetic resonance image(MRI) revealed the expanded cystic lesion at C7/T1 level which compressed the cord from left side. After administration of steroid, surgical resection was performed via posterior approach and partial laminectomy. The dural expansion was observed after total removal of cyst which was diagnosed as a pathologist and symptoms were completely recovered. Because of its possibility of expansion of the synovial cyst and critical myelopathic symptoms can be induced in cervical spine, immobilization should be in consideration for acute period of post-trauma, especially, in old-aged patients with degenerative facet joints. And surgical procedure should not be delayed if symptoms developed.

Delayed Carotid Wallstent Shortening Resulting in Restenosis Following Successful Carotid Artery Angioplasty and Stenting

Carotid angioplasty and stenting (CAS) for carotid stenosis has been increasingly used as an alternative treatment in patients not eligible for surgery. Even though CAS can be performed relatively simply in many cases, various complications can occur. We report four cases of CAS using the Carotid Wallstent, which were complicated by delayed shortening of the stent, resulting in restenosis after successful CAS.

Useful parameters utilizing perfusion CT study to evaluate the hemodynamic status in chronic ischemic stroke patients / 대한뇌혈관외과학회지

OBJECTIVE: Perfusion-computed tomography (CT) is useful and quick diagnostic tool for evaluating ischemic stroke patients. We evaluated three measurement maps, cerebral blood flow (CBF), cerebral blood volume (CBV) and time to peak (TTP) for their usefulness in deciding on revascularization surgery using CT parameters after single photon emission computed tomography (SPECT) findings in chronic steno-occlusive disease patients. METHODS: We retrospectively investigated 47 patients with unilateral internal carotid artery (ICA) or middle cerebral artery (MCA) steno-occlusive disease . All patients underwent digital subtraction angiography (DSA) as well as an acetazolamide challenge with SPECT and perfusion CT. Patients who showed decreased reserve capacity with a Diamox challenge were classified in the positive group, whereas patients who had no difference in reserve capacity were placed in the negative group. RESULTS: Thirty-one patients were positive and the remaining 16 were negative. Differences in rCBV and rCBF parameters between normal cerebral hemispheres and cerebral hemispheres with steno-occlusive disease did not correlate with SPECT results, but TTP values did. SPECT results seemed relevant when TTP differences between hemispheres with normal and steno-occlusive disease were more than 1.55 times. CONCLUSION: Perfusion CT is a useful tool for the rapid, adequate diagnosis of large territorial infarcts, and the TTP map of perfusion CT is a sensitive and reliable parameter to show the status of collateral circulation in chronic cerebrovascular ischemic disease.

Cerebral Infarction due to Mucormycosis in the Cavernous Sinus / 대한뇌혈관외과학회지

Rhinocerebral mucormycosis is the most common fungal infection and is frequently seen in patients with poorly controlled diabetes mellitus. We report a rare case of cavernous sinus mucormycosis in a 70-year-old man with insulin-dependent diabetes mellitus. An endoscopic surgical removal of the mucocele was performed. The histopathologic examination revealed characteristic aseptate branching hyphae with invasion of blood vessels, which is consistent with zygomycosis. The patient was administered high-dose amphotericin B therapy. While undergoing amphotericin-B treatment, the patient developed a left-sided hemiparesis. Magnetic resonance imaging and magnetic resonance angiography revealed acute infarction in the right hemisphere and occlusion of the right internal carotid artery in the right cavernous sinus. The patient was managed with conventional medical treatment for acute cerebral infarction and additional amphotericin B infusion. The patient survived, but with severe neurologic sequelae despite extensive medical therapy, including complete-visual loss, leftsided hemiparesis, impairment of cognitive function, dysphagia, and neuropathic pain on the left side of the body. We report herein the clinical course and treatment of a patient with cerebral complications due to mucormycosis and also present a brief literature review.

An Unexpected Huge Hematoma after Iliac Artery Injury as a Rare Complication at an Anterior Iliac Bone Graft Donor Site: A Case Report

Even through there are many reported complications of the iliac bone donor site during anterior cervical spine surgery, vascular injuries are very rare, especially deep circumflex iliac artery(DCIA) injury encountered after harvesting of a bone graft. A 68-year-old female was presented with neck pain and recent progressive weakness due to dislocation and instability of C5/6 with cord compression. Corpectomy and inter-body fusion from C5 to 7 was done without any definite perioperative complications including the iliac donor site. On the 2nd post-operative day, a huge hematoma and active bleeding at the retroperitoneal site was found by computed tomography and angiography revealed bleeding from DCIA. The authors report a case of massive bleeding due to DCIA injury that was difficult to control and managed by selective arterial embolization.

Embolization through the Ophthalmic Artery with Onyx in Bilateral Ethmoidal Dural Arteriovenous Fistula: A Case Report / 대한뇌혈관외과학회지

Endovascular treatment of ethmoidal dural arteriovenous fistula (DAVF) has not been widely performed because of the technical difficulty of the procedure and the potential risk of central retinal artery occlusion. We report the case of a patient who underwent Onyx embolization through the ophthalmic artery in bilateral ethmoidal DAVF; to our best knowledge this is the first report.

Spontaneous Bilateral Basal Ganglia Hemorrhage: Case Report / 대한뇌혈관외과학회지

A 39-year old man presented with comatose mentality. Brain computerized tomography revealed bilateral basal ganglia hemorrhage. The amount of hematoma was 35 cc each. He had no hypertension history through out regular health examination. Emergenct hematoma evacuation was performed. Histopathologic study disclosed no evidence of amyloid angiopathy or infection. He died 4 days after the operation due to myocardiac infarction. This report describe a rare case of simultaneous bilateral cerebral hemorrhages without history of hypertension.

Is Extravasation of Radiographic Contrast a Predictor of Hematoma Enlargement in Spontaneous Supratentorial Intracerebral Hemorrhage? / 대한뇌혈관외과학회지

BACKGROUND AND PURPOSE: The enlargement of a hematoma occurs commonly in patients with spontaneous intracerebral hemorrhage (ICH) after hospitalization and can worsen the clinical outcome. We conducted this study to determine whether extravasation of a radiographic contrast agent is a predictor of hematoma enlargement occurring after admission in patients with spontaneous ICH. METHODS: We reviewed the clinical records and computerized tomography (CT) scan findings of 384 patients with spontaneous ICH admitted within 24 hours of ictus from 2002 to 2005. Only 71 patients with primary ICH in the basal ganglia or thalamus were included in the study. The first CT scan was preformed within 24 hours of onset and the second CT scan was preformed within 72 hours of onset. We compared patients with and without hematoma enlargement according to the radiological findings, clinical characteristics and laboratory data. RESULTS: Seventeen patients (23.9%) showed hematoma enlargement after admission. Extravasation of the radiographic contrast agent on a CT scan was seen in 23 patients (32.4%). The presence of contrast extravasation on a CT scan closely correlated with evidence of hematoma enlargement, as seen on a follow-up CT scan (p = 0.000). Other variables did not reach statistical significance for the independent association with hematoma enlargement. CONCLUSIONS: Due to a high risk for hematoma enlargement, patients with spontaneous ICH in the basal ganglia and thalamus, especially those with evidence of contrast extravasation on a CT scan, should be closely observed. Short term followup radiological studies are needed for the verification of hematoma enlargement.

Recanalization Rate and its Associated Factors after Intravenous Tissue Plasminogen Activator Thrombolysis for Acute Major Cerebral Arterial Occlusion / 대한뇌혈관외과학회지

PURPOSE: To investigate the recanalization rate after intravenous administration of recombinant tissue plasminogen activator (IV-tPA) for acute major arterial occlusion of the anterior cerebral circulation and to investigate the relationship between atrial fibrillation and recanalization. METHODS: From April 2005 to April 2006, 16 patients with acute major arterial occlusion of the anterior cerebral circulation were treated with IV-tPA. Recanalization was classified as good (as compared with an unoccluded contralateral vessel; thrombolysis in myocardial infarction (TIMI) classification grade II and III) and poor (TIMI grade 0 and I). The clinical and radiological parameters associated with recanalization were analyzed. The clinical outcomes were evaluated by use of the National Institute of Health Stroke Scale (NIHSS) at 3 months after treatment. RESULTS: Of all of the 16 patients, 11 patients (68.8%) showed good recanalization. Among these 11 patients, nine patients survived (81.8%). However, only one patient survived (20%, p = 0.036) of the other five patients who showed poor recanalization. The pretreatment NIHSS score and atrial fibrillation were significantly correlated with the recanalization rate. Atrial fibrillation was found in 8 of 16 patients (50.0%) as the cause of the cerebral embolic infarction. Among the patients with atrial fibrillation only three patients showed good recanalization (37.5%); patients without atrial fibrillation showed good recanalization (100%, p = 0.026). CONCLUSIONS: I.-tPA appears to be effective and safe as a recanalization method for acute major cerebral arterial occlusion in patients that do not have atrial fibrillation. Good recanalization was associated with a good clinical result. Atrial fibrillation is a significant associated factor of poor recanalization and high mortality.

The Effect of Recombinant Tissue Plasminogen Activator on the Intracerebral Hematomas in Experimental Cat Models

OBJECTIVE: Recent clinical studies have demonstrated that intracisternal administration of recombinant tissue plasminogen activator(rt-PA) can facilitate the normal clearing of blood from the subarachnoid space. Urokinase, a first generation fibrinolytic agent, has been used to liquify such clots with some success. Therefore, recombinant tissue plasminogen activator, a second generation fibrinolytic drug that may be safer and more effective, is studied to evaluate its dosage to lyse clots in vitro and reactivity in the brain parenchyme. METHODS: Intracerebral hematomas were created by stereotactically injecting 2ml of clotted autogenous blood into the brain parenchyme of total 28 anesthetized adult cats (weighting 3.8 to 4.1kg). The control animals (group A) received 1ml of normal saline injected into the clots and the experimental animals received each 0.1mg of rt-PA (group B), 0.5mg of rt-PA (group C) and 1mg of rt-PA (group D) at 6 hours after the clot injection. RESULTS: 1. The amount of remained clots after lysing the hematomas were as follows: 1.80+/-0.17ml in group A, 1.65+/-0.23ml in group B, 0.61+/-0.37ml in group C and 0.52+/-0.34 in group D. The result indicated that hematomas in rt-PA treated groups (C & D) were lysed better than the control group. 2. At least 0.5mg of rt-PA should be required for the lysis of 2ml of hematomas. 3. Light microscopic examination revealed no histological evidence of hemorrhage in tissue sections from each brain. CONCLUSION: Recombinant tissue plasminogen activator may be safely and effectively employed for the lysis of intracerebral hematomas in animal model.

Intrasellar Schwannomas

The authors present two cases of intrasellar schwannoma, a condition rarely reported in the literature. The patients presented with symptoms of hypopituitarism. Sellar magnetic resonance imaging(MRI) revealed intrasellar masses extending into the suprasellar region, with the normal pituitary gland also identifiable in the imaging study. The tumors were removed via trans-sphenoidal route, and found to be very firm, unlike usual pituitary adenomas. Tissue diagnosis confirmed the tumors as schwannoma.

Comparative Study of Cerebral Vasospasm between Endovascular Treatment and Conventional Surgery of Acutely Ruptured Aneurysms: Clinical Study / 대한뇌혈관외과학회지

OBJECT: Generally, it seems like that the incidence of vasospasm of vasospasm in endovascular coil embolization is higher than clipping in aneurysmal subarachnoid hemorrhage. But endovascular coil embolization in our study group was not associated with higher incidence of symptomatic vasospasm than direct clipping and we made an analysis of that cause. METHODS: The authors reviewed 220 patients with aneurysmal subarachnoid hemorrhage who had been treated with either neck clipping or coil embolization by a single surgeon between January 1997 and December 2002. Poor initial grade (Hunt & Hess grade IV & V) patients were excluded. Finally 171 patients were enrolled in this study. 126 patients(74%) underwent direct surgical clipping and 45 patients (26%) underwent endovascular treatments of their aneurysms. RESULTS: Overall symptomatic vasospasm occurred in 32 (19%) patients, 4 of 45 patients (9%) were coiling group and 28 of 126 (22%) were surgically treated group. There was no difference between two groups in age, initial Hunt & Hess grade, Glasgow coma scale, operation time, treatment initiation time, patient's medical status. CONCLUSIONS: Patients who underwent coil embolization were not more likely to suffer from symptomatic vasospasm than aneurysm neck clipping in better clinical grades (Hunt & Hess grade of I to III) patients in our institute.