Seong Rim Kim

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

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.

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 Allens 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.

Predictors of malignant brain edema in middle cerebral artery infarction observed on CT angiography

Patients with middle cerebral artery (MCA) infarction accompanied by MCA occlusion with or without internal carotid artery (ICA) occlusion have a poor prognosis, as a result of brain cell damage caused by both the infarction and by space-occupying and life-threatening edema formation. Multiple treatments can reduce the likelihood of edema formation, but tend to show limited efficacy. Decompressive hemicraniectomy with duroplasty has been promising for improving functional outcomes and reducing mortality, particularly improved functional outcomes can be achieved with early decompressive surgery. Therefore, identifying patients at risk for developing fatal edema is important and should be performed as early as possible. Sixty-four patients diagnosed with major MCA infarction with MCA occlusion within 8 hours of symptom onset were retrospectively reviewed. Early clinical, laboratory, and computed tomography angiography (CTA) parameters were analyzed for malignant brain edema (MBE). Twenty of the 64 patients (31%) had MBE, and the clinical outcome was poor (3month modified Rankin Scale >2) in 95% of them. The National Institutes of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early Computed Tomography Score, Clot Burden Score, and Collateral Score (CS) showed statically significant differences in both groups. Multivariable analyses adjusted for age and sex identified the independent predictors of MBE: NIHSS score >18 (odds ratio [OR]: 4.4, 95% confidence interval [CI]: 1.2-16.0, p=0.023) and CS on CTA <2 (OR: 7.28, 95% CI: 1.7-30.3,p=0.006). Our results provide useful information for selecting patients in need of aggressive treatment such as decompressive surgery.

Treatment of the Superior Sagittal Sinus Thrombosis with the Mechanical Thrombectomy Using Stent-Retriever Device.

Cerebral venous sinus thrombosisis an uncommon entity and its clinical presentations are highly variable. We present the case of superior sagittal sinus thrombosis. Although it was medical refractory, successfully treated with mechanical thrombectomy using the Solitaire FR device. A 27-year-old man who presented with venous infarction accompanied by petechial hemorrhage secondary to the superior sagittal sinus (SSS) thrombosis. Due to rapid deterioration despite of anticoagulation therapy, the patient was taken for endovascular treatment. We deployed the Solitaire FR device (4×20 mm) in the anterior portion of the thrombosed SSS, and it was left for ten minutes before the retraction. Thus, we removed a small amount of thrombus. But the sinus remained occluded. We therefore performed the thrombectomy using the same methods using the Solitaire FR (6×20 mm). Thus, we were successful in removing larger clots. Our case highlights not only that the mechanical thrombectomy using the Solitaire FR is effective in achieving revascularization both rapidly and efficiently available, but also that it might be another option in patients with cerebral venous sinus thrombosis who concurrently had rapid clinical deterioration with devastating consequences.

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.

Headache Outcomes After Coil Embolization in Patients with Unruptured Intracranial Aneurysms: Do They Get Better or Worse? A Prospective Analysis

BACKGROUND To investigate the association between headache outcomes and coil embolization and to identify potential factors associated with different headache outcomes in patients with unruptured intracranial aneurysms (UIAs) after treatment with coil embolization. METHODS A prospective study of patients with planned coil embolization for UIAs was conducted. The changes in headache patterns, headache-related disability, and depression were assessed before coil embolization and at 3 days and 2 and 6 weeks after coil embolization. All variables were analyzed to identify factors associated with different headache outcomes. RESULTS Fifty-nine (72%) of 82 patients reported headaches before coil embolization. Of these, improvements in the severity of headaches were reported by 42 patients (71%). In addition to a significant reduction in headache severity, significant reductions in headache-related disability and depression scores also were observed. Demographic factors, aneurysmal characteristics, or procedural factors were not found to be significantly associated with improvement in the severity of headaches after coil embolization. In addition, the number of microemboli on diffusion-weighted imaging was not significantly associated with improvement of headaches after coil embolization. Twenty-three patients reported no headaches before coil embolization, and 3 (13%) patients reported new-onset headaches after coil embolization. All new-onset headaches were mild and dull in nature without combined symptoms in the temporal area. CONCLUSIONS Our study suggested that regardless of headache characteristics, the aneurysm size (even those <5 mm in diameter), technique used (stent-assisted or not stent-assisted), and coil embolization of UIAs resulted in headache improvement in most patients with pretreatment headaches.

Usefulness and stability of intraoperative digital subtraction angiography using the trans-radial route in arteriovenous malformation surgery

BACKGROUND Digital subtraction angiography is the gold standard to confirm complete removal of an arteriovenous malformation (AVM) nidus. However, the transfemoral approach requires specialized instrumentation and is cumbersome and difficult to perform with the patient in the prone or decubitus position. We report the use of intraoperative digital subtraction angiography (iDSA) with the transradial approach and examine its usefulness and safety. MATERIALS AND METHODS We retrospectively reviewed clinical features, radiologic images, surgical findings, and iDSA findings of patients with AVM who underwent surgery for nidus removal. Transradial iDSA was performed within 30 minutes for patients who required angiographic confirmation after AVM resection. This procedure was simple with the radial arterial line for blood pressure monitoring used as digital subtraction angiography catheter access route. RESULTS Transradial iDSA was performed in 23 patients. Twelve patients were not in the general supine position during neurosurgery; 7 patients were operated on in prone position, and 5 patients were operated on in the park bench position. Remnant nidus was identified by iDSA in 2 patients, and additional measures were required. CONCLUSIONS Intraoperative cerebral angiography during surgery for cerebral AVM could be performed safely via the transradial approach. This approach showed several merits in terms of easy access; no extra requirements, such as preoperative sheath implantation, anticoagulation during the surgery, or a radiolucent table; and usefulness in any surgical position. Further studies using this approach and comparison with the transfemoral approach are necessary.

Perfusion-Weighted MRI Parameters for Prediction of Early Progressive Infarction in Middle Cerebral Artery Occlusion

Objective Early progressive infarction (EPI) is frequently observed and related to poor functional outcome in patients with middle cerebral artery (MCA) infarction caused by MCA occlusion. We evaluated the perfusion parameters of magnetic resonance imaging (MRI) as a predictor of EPI. Methods We retrospectively analyzed patients with acute MCA territory infarction caused by MCA occlusion. EPI was defined as a National Institutes of Health Stroke Scale increment ≥2 points during 24 hours despite receiving standard treatment. Regional parameter ratios, such as cerebral blood flow and volume (rCBV) ratio (ipsilateral value/contralateral value) on perfusion MRI were analyzed to investigate the association with EPI. Results Sixty-four patients were enrolled in total. EPI was present in 18 (28%) subjects and all EPI occurred within 3 days after hospitalization. Diabetes mellitus, rCBV ratio and regional time to peak (rTTP) ratio showed statically significant differences in both groups. Multi-variate analysis indicated that history of diabetes mellitus [odds ratio (OR), 6.13; 95% confidence interval (CI), 1.55–24.24] and a low rCBV ratio (rCBV, <0.85; OR, 6.57; 95% CI, 1.4–30.27) was significantly correlated with EPI. Conclusion The incidence of EPI is considerable in patients with acute MCA territory infarction caused by MCA occlusion. We suggest that rCBV ratio is a useful neuro-imaging parameter to predict EPI.

Clinical Utility of Angiographic CT with a Flat-detector Angiographic System during Endovascular Procedure

Objective We evaluated the feasibility of angiographic computed tomography (ACT) for visualizing stent material in patients who underwent intracranial or extracranial stent placement to treat atherosclerotic lesions or stent assisted coil embolization. Materials and Methods We performed intrarterial and intravenous ACT on biplane angiography system equipped with flat panel detectors (Axiom Arits dBA; Siemens Medical Solutions, Forchheim, Germany). Vistipaque 320 was injected for contrast medium, total 150 mL at flow rate of 5 mL/s through artery and 77 mL at flow rate of 3.5 mL/s through vein. Results ACT is a new imaging modality that provides a clear visualization of stent strut. Conclusion Therefore this new application has potential to become the noninvasive option for follow-up after endovascular surgery using stents.