Gyojun Hwang

Thromboembolic complications of elective coil embolization of unruptured aneurysms: the effect of oral antiplatelet preparation on periprocedural thromboembolic complication.

OBJECTIVEWe retrospectively evaluated whether antiplatelet preparation lowered the thromboembolic complication rate during the perioperative period. METHODSWe reviewed 328 elective coil embolization procedures in which only microcatheters were used for coiling. No antiplatelet medication was prescribed before the procedure in 95 cases (29%, group 1), whereas antiplatelet therapy was used in 233 cases (71%, group 2; 61 [18.6%] with a single agent [aspirin or clopidogrel] and 172 [52.4%] with both agents). Antiplatelet agents were not given after coiling unless atherosclerosis, severe coil protrusion, or a thromboembolic complication occurred during the procedure. A thromboembolic complication was defined as a procedural thromboembolic event or transient ischemic attack or stroke occurring within 2 days of embolization. RESULTSThromboembolic complications occurred in 11 cases (3.4%): 6 (6.3%) in group 1 and 5 (2.1%) in group 2 (P = .085). In 195 cases (59.5%) treated by the single microcatheter technique, the risk of thromboembolic complications was low and not affected by antiplatelet preparation (1.8% [no preparation] vs 2.2% [preparation]; P = 1.000). However, in 133 cases (40.5%) treated by the multiple microcatheter technique, antiplatelet preparation significantly reduced the thromboembolic complication risk by 85.2% (12.8% [no preparation] vs 2.1% [preparation]; odds ratio, 0.148; 95% confidence interval, 0.027–0.798; P = .023). The aneurysms treated by the multiple microcatheter technique had more complex configurations for coiling (P < .001). The risk of hemorrhage was not increased by antiplatelet preparation (P = .171). CONCLUSIONAntiplatelet preparation lowered the periprocedural thromboembolic complication rate in unruptured aneurysms treated by the multiple microcatheter technique and did not increase the risk of hemorrhage. Therefore, antiplatelet preparation can help to reduce complications in patients in whom technical difficulties are expected without the risk of hemorrhage.

Comparison of 2-year angiographic outcomes of stent- and nonstent-assisted coil embolization in unruptured aneurysms with an unfavorable configuration for coiling.

BACKGROUND AND PURPOSE: Stents are known to have hemodynamic and biologic effects in addition to their mechanical scaffold effect. To determine whether stents affect long-term outcomes after coiling of unruptured aneurysms, we compared angiographic outcomes at 2 years postembolization for stent- and nonstent-assisted coiled unruptured aneurysms. MATERIALS AND METHODS: Stent-assisted coiling was used in unruptured aneurysms unfavorable for simple coiling (neck size >4 mm and dome-to-neck ratio <1.5) in our practice. Therefore, 126 coiled unruptured aneurysms in total (40 [31.7%] stent group and 86 [68.3%] nonstent group) with these conditions were selected for this study. The nonstent group aneurysms were treated with multiple microcatheter technique (53 cases) or balloon-assisted technique (33 cases). Self-expandable stents were used for coiling in stent group aneurysms. No significant difference in aneurysmal characteristics (aneurysm type [sidewall/bifurcation], diameter, neck size, and dome-to-neck ratio) or angiographic outcome at embolization (packing attenuation, obliteration grade, and contrast filling) were observed between the 2 study groups. RESULTS: At 2-year follow-up visits, rates of progressive occlusion (stent group, 17/40 [42.5%] versus nonstent group, 34/86 [39.5%]) and recanalization (7/40 [17.5%] versus 18/86 [21.0%]) did not show a statistically significant difference between the 2 groups (P = .895). CONCLUSIONS: The present study did not show that additional hemodynamic and biologic effects of stents designed for neck remodeling were enough to enhance progressive occlusion and prevent the recanalization of unruptured aneurysms. Our finding suggests that stent placement provides no better long-term angiographic outcomes for unruptured aneurysms with an unfavorable configuration for coiling.

Stroke prevention by direct revascularization for patients with adult-onset moyamoya disease presenting with ischemia

OBJECT Moyamoya disease (MMD) is a progressive disease that can cause recurrent stroke. The authors undertook this retrospective case-control study with a large sample size in an attempt to assess the efficacy of direct or combined revascularization surgery for ischemia in adults with MMD. METHODS The authors investigated cases involving patients with moyamoya disease presenting with ischemia who visited Seoul National University Bundang Hospital and Seoul National University Hospital between 2000 and 2014. Among 441 eligible patients, 301 underwent revascularization surgery and 140 were treated conservatively. Variables evaluated included age at diagnosis, sex, surgical record, Suzuki stage, and occurrence of stroke. Patients were stratified into 2 groups based on whether or not they had undergone revascularization surgery. Actuarial 1-, 5-, and 10-year stroke rates were calculated using the life table method. Risk factor analysis for 5-year stroke occurrence was conducted with multivariate regression. RESULTS Of the 441 patients, 301 had been surgically treated (revascularization group) and 140 had not (control group). The mean follow-up durations were 45 and 77 months, respectively. The actuarial 10-year cumulative incidence rate for any kind of stroke was significantly lower in the revascularization group (9.4%) than in the control group (19.6%) (p = 0.041); the relative risk reduction (RRR) was also superior (52.0%) in the revascularization group, and the number needed to treat was 10. The 10-year rate of ischemic stroke was greater (13.3%) in the control group than in the revascularization group (3.9%) (p = 0.019). The RRR for ischemic stroke in the revascularization group was 70.7%, and the number needed to treat was 11. However, the actuarial 1- and 5-year rates of ischemic stroke did not significantly differently between the groups. Overall, revascularization surgery was shown to be an independent protective factor, as revealed by multivariate analysis. CONCLUSIONS Direct or combined revascularization for patients with adult-onset moyamoya disease presenting with ischemia can prevent further stroke.

Standard vs Modified Antiplatelet Preparation for Preventing Thromboembolic Events in Patients With High On-Treatment Platelet Reactivity Undergoing Coil Embolization for an Unruptured Intracranial Aneurysm: A Randomized Clinical Trial

IMPORTANCE Thromboembolism is the most common complication in coiling for an unruptured aneurysm and is frequent in patients with high on-treatment platelet reactivity (HTPR) who are prescribed a standard antiplatelet preparation for its prevention. OBJECTIVE To evaluate the effect of a modified antiplatelet preparation compared with a standard preparation in patients with HTPR undergoing coiling. DESIGN, SETTING, AND PARTICIPANTS A prospective randomized open-label active-control trial with blinded outcome assessment at the Seoul National University Bundang Hospital from May 27, 2013, to April 7, 2014. Patients with HTPR were randomly assigned (1 to 1) to the standard or modified preparation group. Patients without HTPR were assigned to the non-HTPR group. A total of 228 patients undergoing coiling for unruptured aneurysms were enrolled and allocated to the study, 126 in the HTPR group (63 to the standard preparation group and 63 to the modified preparation group) and 102 to the non-HTPR group. Intent-to-treat analysis was performed. INTERVENTIONS The modified preparation (HTPR to aspirin, 300 mg of aspirin and 75 mg of clopidogrel bisulfate; and HTPR to clopidogrel, 200 mg of cilostazol added to the standard regimen) was performed before coiling in the modified preparation group. Standard preparation (100 mg of aspirin and 75 mg of clopidogrel) was maintained in the standard preparation and non-HTPR groups. MAIN OUTCOMES AND MEASURES The primary outcome was a thromboembolic event defined as thromboembolism during coiling and a transient ischemic attack or ischemic stroke within 7 days after coiling. The principal secondary outcome was a bleeding complication according to Thrombolysis in Myocardial Infarction bleeding criteria within 30 days after coil embolization. RESULTS The thromboembolic event rate was low in the modified preparation group (1 of 63 [1.6%]) compared with the standard preparation group (7 of 63 [11.1%]; adjusted risk difference, -11.7% [95% CI, -21.3% to -2.0%]; P = .02), which had a higher thromboembolic risk than the non-HTPR group (1 of 102 [1.0%]; adjusted risk difference, 8.6% [95% CI, 1.0% to 16.3%]; P = .03). All bleeding complications were of minimal grade according to Thrombolysis in Myocardial Infarction bleeding criteria. The bleeding rate was not different between the modified (6 of 63 [9.5%]) and standard (4 of 63 [6.3%]) preparation groups (adjusted risk difference, 5.6% [95% CI, -4.2% to 15.4%]; P = .26). CONCLUSIONS AND RELEVANCE Modified antiplatelet preparation for patients with HTPR compared with standard antiplatelet preparation reduced the thromboembolic event rate in coiling for an unruptured aneurysm without increasing bleeding. TRIAL REGISTRATION Clinical Research Information Service Identifier: KCT0000804.

Superficial Temporal Artery to Middle Cerebral Artery Bypass in Acute Ischemic Stroke and Stroke in Progress

BACKGROUND:Surgical reperfusion may be beneficial in patients with acute ischemic stroke who are ineligible for thrombolysis. OBJECTIVE:To evaluate the outcome of superficial temporal artery to middle cerebral artery (STA-MCA) bypass in acute stroke and stroke in progress. METHODS:The clinical and radiological data of 9 patients treated by STA-MCA bypass requiring urgent reperfusion but ineligible for intra-arterial thrombolysis (IAT) were reviewed. Pooled analysis was performed of published literature concerning STA-MCA bypass in acute stroke (21 cases in 2 articles). RESULTS:Of the 9 patients enrolled, symptom aggravation occurred during medical treatment in 4 patients and after IAT in 2. Three patients were ineligible for IAT despite being within 8 hours of symptom onset. Bypass significantly improved National Institutes of Health Stroke Scale scores (preoperatively, 12.4 ± 4.88; 3 days postoperatively, 8.6 ± 6.39, P = .046; discharge, 5.4 ± 5.15, P = .008; 3 mo postoperatively 3.7 ± 4.82, P = .008) without significant infarction growth by diffusion weighted imaging (preoperatively, 15.0 ± 8.87 mL; 7 days postoperatively, 15.2 ± 8.28 mL; P = .110). Abnormal perfusion regions (mean transit time >145% of contralateral side value) were reduced in all cases (2.63 ± 0.93 mL). Good outcomes (modified Rankin scale ≤2) were achieved by 6 patients. Pooled analysis with our patients showed a significant neurological improvement (P < .001) and a good outcome in 25 (83.3%) patients without hemorrhage or complication. CONCLUSION:STA-MCA bypass may be beneficial to patients with acute stroke or stroke in progress who are ineligible for IAT. Furthermore, it appears safe when the infarction is small. These findings indicate that STA-MCA bypass could be considered as a treatment option in selected patients with acute stroke or stroke in progress.

Delayed Ischemic Stroke after Stent-assisted Coil Placement in Cerebral Aneurysm: Characteristics and Optimal Duration of Preventative Dual Antiplatelet Therapy

PURPOSE To evaluate characteristics of delayed ischemic stroke after stent-assisted coil placement in cerebral aneurysms and to determine the optimal duration of dual antiplatelet therapy for its prevention. MATERIALS AND METHODS This retrospective study was approved by the institutional review board, and the requirement to obtain written informed consent was waived. Of 1579 patients with 1661 aneurysms, 395 patients (25.0%) with 403 aneurysms (24.3%) treated with stent-assisted coil placement were included and assigned to groups stratified as early (126 patients [31.9%]; 3 months of coil placement), midterm (160 patients [40.5%]; 6 months), or late (109 patients [27.6%]; ≥ 9 months), according to the time points of switching dual antiplatelet therapy to monotherapy from coil placement. Cumulative rates of delayed ischemic stroke in each group were calculated by using Kaplan-Meier estimates that were compared with log-rank tests. Risk factors of delayed ischemic stroke were identified by using Cox proportional hazard analysis. RESULTS Delayed ischemic stroke occurred in 3.5% of all cases (embolism, 3.0%; thrombotic occlusion, 0.5%) within 2 months following the switch. Late switch yielded no delayed ischemic stroke, unlike early (seven of 126 patients [5.6%]; P = .013) or midterm (seven of 160 patients [4.4%]; P = .028) switch. Incomplete occlusion (hazard ratio, 6.68 [95% confidence interval: 1.490, 29.900]) was identified as a risk factor. CONCLUSION Delayed ischemic stroke after stent-assisted coil placement is caused by embolism from or thrombotic occlusion of stent-containing vessels after switching from dual antiplatelet therapy to monotherapy. The stent-containing vessel with incomplete aneurysm occlusion presents as a long-term thromboembolic source. Therefore, dual antiplatelet therapy for more than 9 months and late switch to monotherapy are recommended for its prevention.

Partial Recovery after Intraarterial Pharmacomechanical Thrombolysis in Ophthalmic Artery Occlusion following Nasal Autologous Fat Injection

Although autologous fat injection into the face is a widely used procedure in aesthetic surgery, heed must be taken because it may cause severe complications related to inadvertent arterial embolization, including stroke and vision loss. Vision loss may originate from ophthalmic artery occlusion, and no therapeutic options have yet been reported for this condition. Herein, the authors report a case of ophthalmic artery occlusion following nasal autologous fat injection. Partial recovery of choroidal and retinal perfusion, ocular motility, and corneal clarity was achieved after intraarterial pharmacomechanical thrombolysis.

Epidemiology of Moyamoya Disease in Korea: Based on National Health Insurance Service Data

There have been a few studies reporting the epidemiology of moyamoya disease in Korea. Previous studies revealed relatively high prevalence and incidence of moyamoya disease in Korea and Japan. This study was designed to provide the latest epidemiologic information of moyamoya disease in Korea. We analyzed a database comprising of 50 million people covered in Korea by the National Health Insurance Service to calculate the prevalence. The incidence was estimated by eliminating the duplicated records of previous 3 years. We summarized the prevalence and incidence according to age, sex, and local distribution. In addition, the chronological changes were demonstrated with direct standardization using the 2010 population structure information. The standardized prevalence was 6.5 per 100000 persons in 2005, which was increased to 18.1 in 2013. In the same period, standardized incidence was increased from 2.7 to 4.3 per 100000 persons. The prevalence for men was 4.9 and 8.3 for women in 2005. In 2013, the prevalence had increased for men and women to 13.8 and 25.3, respectively. The incidence for men and women was 2.2 and 3.2, respectively, in 2005. It had increased to 3.5 and 5.7, respectively. The mean age of patients was 33.5 in 2005 and increased to 42.5 in 2013. The peak prevalent age group had shifted slightly to the older age groups, with chronologically consistent female predominance. The prevalence was highest in Jeollabuk province and lowest in Ulsan city.

Risk Factor Analysis for the Recurrence of Chronic Subdural Hematoma: A Review of 368 Consecutive Surgical Cases

Objective Chronic subdural hematoma (CSDH) is a common form of extra axial hemorrhage in the elderly. A surgical procedures such as a burr hole trephination are used for the CSDH treatment. The recurrence rate of CSDH is reported to range from 2.3 to 33%. In the current study, we focused on the determination of risk factors associated with the recurrence of CSDH. Methods We retrospectively reviewed 368 consecutive patients with CSDH treated by burr hole trephination. Univariate and multivariate analysis were performed to describe the relationships between clinical and radiological factors as well as the recurrence of CSDH. Results Totally 31 (8.4%) patients experienced a recurrence of CSDH in our study. The male group (10.2%) had a higher recurrence rate than the female group (3.1%). Also patients with malignant neoplasm history showed a high recurrence rate (17.9%). The recurrence rate of single layer CSDH (13.1%) and isodensity CSDH (11.7%) was highly significant also. Conclusion Sex, history of malignant neoplasm and the hematoma type on computed tomography were factors related with the recurrence of CSDH in our study. These findings may be supportive in the identification of patients at risk for a recurrence of CSDH.

The Characteristics and Risk Factors of Headache Development after the Coil Embolization of an Unruptured Aneurysm

Little is known about headaches post-aneurysm coiling. These authors treated 90 patients with unruptured aneurysms and no headaches. Nearly 56% developed headaches within 72 hours of treatment and all headaches resolved shortly thereafter. Only coil-packing attenuation was associated with presence of headaches. The authors concluded that though headaches were common, these were nearly always benign and resolved spontaneously. High packing attenuation may induce stretching of the aneurysm and inflammation that can result in headaches. BACKGROUND AND PURPOSE: Development of a headache after aneurysm coil embolization is not uncommon but has received little attention. The authors prospectively analyze the characteristics and risk factors of a headache after coiling in patients treated for an unruptured cerebral aneurysm. MATERIALS AND METHODS: Ninety patients treated for an unruptured cerebral aneurysm over a period of 1 year, and without a headache history within a month before coiling, were enrolled in this study. All coilings were successfully performed without neurologic complications. After coiling, headache development and intensities were recorded. RESULTS: Fifty (55.6%) patients experienced a headache (VAS score, 4.5 ± 2.02) at 7.9 (range, 0–72) hours, on average, after coiling, and all headaches resolved within an average of 73.0 (range, 3–312) hours. Univariate analysis showed that the following were significantly associated with the development of a headache: age ≤50 years (OR 4.636, 95% CI, 1.414–15.198), hypertension (OR 0.232, 95% CI, 0.095–0.571), a packing attenuation of >25% (OR 3.619, 95% CI, 1.428–9.174), and a previous headache history (OR 2.769, 95% CI, 1.120–6.849). However, binary logistic regression showed that only a packing attenuation of >25% (P = .013, adjusted OR 3.774, 95% CI, 1.320–10.790) and no history of hypertension (P = .019, adjusted OR 3.515, 95% CI, 1.233–10.021) were independently associated with the development of a headache. CONCLUSIONS: A headache frequently developed after the coiling of unruptured aneurysms. However, headaches were relatively benign and resolved within several days. The present study shows that no hypertension history and a packing attenuation of >25% are risk factors of headache development.