Clinical Outcomes of Clipping and Coil Embolization for Ruptured Intracranial Aneurysms Categorized by Region and Hospital Size: A Nationwide Cohort Study in Korea.

BACKGROUND: To analyze the outcomes of clipping and coiling for ruptured intracranial aneurysms (RIAs) based on data from the National Health Insurance Service in South Korea, with a focus on variations according to region and hospital size. METHODS: This study analyzed the one-year mortality rates for patients with RIAs who underwent clipping or coiling in 2018. Coiling was further categorized into non-stent assisted coiling (NSAC) and stent assisted coiling (SAC). Hospitals were classified as tertiary referral general hospitals (TRGHs), general hospitals (GHs), or semi-general hospitals (sGHs) based on size. South Korea's administrative districts were divided into 15 regions for analysis. RESULTS: In 2018, there were 2,194 (33.1%) clipping procedures (TRGH, 985; GH, 827; sGH, 382) and 4,431 (66.9%) coiling procedures (TRGH, 1,642; GH, 2076; sGH, 713) performed for RIAs treatment. Among hospitals performing more than 20 treatments, the one-year mortality rates following clipping or coiling were 11.2% and 16.0%, respectively, with no significant difference observed. However, there was a significant difference in one-year mortality between NSAC and SAC (14.3% vs. 19.5%, P = 0.034), with clipping also showing significantly lower mortality compared to SAC (P = 0.019). No significant differences in other treatment modalities were observed according to hospital size, but clipping at TRGHs had significantly lower mortality than at GHs (P = 0.042). While no significant correlation was found between the number of treatments and outcomes at GHs, at TRGHs, a higher volume of clipping procedures was significantly associated with lower total mortality (P = 0.023) and mortality after clipping (P = 0.022). CONCLUSION: Using Korea NHIS data, mortality rates for RIAs showed no significant variation by hospital size due to coiling's prevalence. However, differences in clipping outcomes by hospital size and volume in TRGH highlight the need for national efforts to improve clipping skills and standardization. Additionally, the higher mortality rate with SAC emphasizes the importance of precise indications for its application.

Size-Related Differences in Computed Tomography Markers of Hematoma Expansion in Acute Intracerebral Hemorrhage.

BACKGROUND: Noncontrast computed tomography (NCCT) markers for hematoma expansion (HE) in intracerebral hemorrhage (ICH) are difficult to be found in small ICHs, of which can also expand. We aimed to investigate whether there were size-related differences in the prevalence of NCCT markers and their association with HE. METHODS: This retrospective analysis of prospectively collected stroke registry included 267 consecutive patients with ICH who underwent baseline NCCT within 12 h of onset. Qualitative NCCT markers, including heterogeneous density and irregular shape, were assessed. Hematoma density, defined as mean Hounsfield unit of hematoma, and hematoma volume were measured by semiautomated planimetry. Hematoma volume was categorized as small (≤ 10 ml) and large (> 10 ml). Associations of NCCT markers with HE were analyzed using multivariable logistic regression analyses. The model performances of NCCT markers and hematoma density were compared using receiver operating characteristic curves. RESULTS: Hematoma expansion occurred in 29.9% of small ICHs and 35.5% of large ICHs. Qualitative NCCT markers were less frequently observed in small ICHs. Heterogeneous density, irregular shape, and hematoma density were associated with HE in small ICH (adjusted odds ratios [95% confidence interval] 3.94 [1.50-10.81], 4.23 [1.73-10.81], and 0.72 [0.60-0.84], respectively), and hematoma density was also related to HE in large ICH (0.84 [0.73-0.97). The model performance was significantly improved in small ICHs when hematoma density was added to the baseline model (DeLong's test, p = 0.02). CONCLUSIONS: The prevalence of NCCT markers and their association with HE differed according to hematoma volume. Quantitative hematoma density was associated with HE, regardless of hematoma size.

Higher oscillatory shear index is related to aneurysm recanalization after coil embolization in posterior communicating artery aneurysms.

BACKGROUND: The recurrence rate of posterior communicating artery (Pcom) aneurysms after endovascular treatment (EVT) is higher than that for aneurysms located in other sites. However, it is still unclear what mechanisms are responsible for the recanalization of cerebral aneurysms. In this investigation, we compared hemodynamic factors related with recanalization of Pcom aneurysms treated by endoluminal coiling using computational fluid dynamics (CFD) with high-resolution three-dimensional digital subtraction angiography images. METHODS: Twenty patients were enrolled. A double-sinogram acquisition was performed with and without contrast injection after coil embolization to get true blood vessel lumen by relatively complementing the first sinogram with the second. Adaptive Cartesian meshing was performed to produce vascular wall objects for CFD simulation. The boundary condition for inlet (ICA) was set for dynamic velocity according to the cardiac cycle (0.8 s). Hemodynamic parameters were recorded at two specific points (branching point of Pcom and residual sac). The peak pressure, peak WSS, and oscillatory shear index (OSI) were recorded and analyzed. RESULTS: The median age was 61.0 years, and 18 patients (90%) were female. During a median follow-up of 12 months, seven (35%) treated aneurysms showed recanalization. The median aneurysm volume was significantly higher, and aneurysm height and neck sizes were significantly longer in the recanalization group than those in the stable group. At the branching point of the Pcom, the peak pressure, peak WSS, or OSI did not significantly differ between the two groups. The only statistically significant hemodynamic parameter related with recanalization was the OSI at the aneurysm point. Multivariate logistic regression showed that with an increase of 0.01 OSI at the aneurysm point, the odds ratio for the aneurysm recanalization was 1.19. CONCLUSIONS: A higher OSI is related with recanalization after coil embolization for a Pcom aneurysm.

Clinical Outcomes of Clipping and Coiling in Elderly Patients with Unruptured Cerebral Aneurysms: a National Cohort Study in Korea.

BACKGROUND: We aimed to analyze outcomes of clipping and coiling in treating unruptured intracranial aneurysms (UIAs) in elderly patients and to identify the age at which perioperative risk increases based on national cohort data in South Korea. METHODS: The incidence of perioperative intracranial hemorrhage (ICRH), perioperative cerebral infarction (CI), mortality, and moderate to severe disability data of the patients who underwent coiling or clipping for UIAs were retrieved. Estimated breakpoint (EBP) was calculated to identify the age at which the risk of treatment increases. RESULTS: A total of 38,207 patients were treated for UIAs. Among these, 22,093 (57.8%) patients underwent coiling and 16,114 (42.2%) patients underwent clipping. The incidence of ICRH, requiring a secondary operation, within 3 months in patients ≥ 65 years that underwent coiling and clipping was 1.13% and 4.81%, respectively, and that of both groups assessed were significantly higher in patients ≥ 75 years (coiling, P = 0.013, relative risk (RR) 1.81; clipping, P = 0.015) than younger patients. The incidence of CI within 3 months in patients aged ≥ 65 was 13.90% and 9.19% in the coiling and clipping groups, respectively. The incidence of CI after coiling in patients aged ≥ 75 years (P < 0.001, RR 1.96) and after clipping in patients aged ≥ 70 years (P < 0.001, RR 1.76) was significantly higher than that in younger patients. The mortality rates within 1 year in patients with perioperative ICRH or CI were 2.41% and 3.39% for coiling and clipping groups, respectively, in patients ≥ 65. These rates increased significantly at age 70 in the coiling group and at age 75 for the clipping group (P = 0.012 and P < 0.001, respectively). CONCLUSION: The risk of treatment increases with age, and this risk increases dramatically in patients aged ≥ 70 years. Therefore, the treatment decisions in patients aged ≥ 70 years should be made with utmost care.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma.

Purpose To evaluate the effect of middle meningeal artery (MMA) embolization on chronic subdural hematoma (CSDH) and compare the treatment outcomes of MMA embolization and conventional treatment. Materials and Methods All consecutive patients 20 years or older with CSDH were assessed for eligibility. CSDHs with a focal location, a thickness of 10 mm or less, no mass effect, or underlying conditions were excluded. Seventy-two prospectively enrolled patients with CSDH underwent MMA embolization (embolization group; as the sole treatment in 27 [37.5%] asymptomatic patients and with additional hematoma removal for symptom relief in 45 [62.5%] symptomatic patients). For comparison, 469 patients who underwent conventional treatment were included as a historical control group (conventional treatment group; close, nonsurgical follow-up in 67 [14.3%] and hematoma removal in 402 [85.7%] patients). Primary outcome was treatment failure defined as a composite of incomplete hematoma resolution (remaining or reaccumulated hematoma with thickness > 10 mm) or surgical rescue (hematoma removal for relief of symptoms that developed with continuous growth of initial or reaccumulated hematoma). Secondary outcomes included surgical rescue as a component of the primary outcome and treatment-related complication for safety measure. Six-month outcomes were compared between the study groups with logistic regression analysis. Results Spontaneous hematoma resolution was achieved in all of 27 asymptomatic patients undergoing embolization without direct hematoma removal. Hematoma reaccumulation occurred in one (2.2%) of 45 symptomatic patients receiving embolization with additional hematoma removal. Treatment failure rate in the embolization group was lower than in the conventional treatment group (one of 72 patients [1.4%] vs 129 of 469 patients [27.5%], respectively; adjusted odds ratio [OR], 0.056; 95% confidence interval [CI]: 0.011, 0.286; P = .001). Surgical rescue was less frequent in the embolization group (one of 72 patients [1.4%] vs 88 of 469 patients [18.8%]; adjusted OR, 0.094; 95% CI: 0.018, 0.488; P = .005). Treatment-related complication rate was not different between the two groups (0 of 72 patients vs 20 of 469 patients [4.3%]; adjusted OR, 0.145; 95% CI: 0.009, 2.469; P = .182). Conclusion MMA embolization has a positive therapeutic effect on CSDH and is more effective than conventional treatment. © RSNA, 2017.

Risk factor analysis of recanalization and retreatment for patients with endovascular treatment of internal carotid artery bifurcation aneurysms.

PURPOSE: Only a few reports of internal carotid artery (ICA) bifurcation aneurysms using the endovascular technique have been published in the current literature. The purpose of this study was to assess how multiple risk factors including angioarchitectural features of ICA bifurcation characteristics may have influenced aneurysmal rupture, recanalization, and retreatment. METHODS: Fifty-one patients with 52 ICA bifurcation aneurysms treated with endovascular coiling between July 2003 and July 2015 were retrospectively analyzed. The patients' clinical records, endovascular reports, and clinical and angiographic outcomes were reviewed. We also evaluated risk factors for recanalization and retreatment, including the angioarchitectural anatomy. RESULTS: The clinical outcomes were observed to be satisfactory in 49 patients (96.0%) and unfavorable in 2 patients (4.0%). The risk factor for aneurysmal rupture was young age (P = 0.024). Symptomatic complications due to thromboembolism occurred in 1.9% of cases; no patients suffered a fatal complication. Eleven of 52 ICA bifurcation aneurysms (21.2%) were recanalized within an average of 54.3 ± 33.5 months of follow-up. Among the aneurysms, 4 (7.7%) underwent recoiling. Multivariate analysis showed that ruptured aneurysms (P = 0.006) and a lower packing density (P = 0.048) were risk factors for recanalization. A lower packing density was the only risk factor for retreatment (P = 0.019). CONCLUSION: Endovascular treatment of ICA bifurcation aneurysms is considered safe and acceptable. This study showed that the ICA bifurcation aneurysms ruptured more frequently at a younger age. A higher packing density has been shown to reduce major recanalization and retreatment.

Successful retinal blood flow augmentation after extracranial-intracranial bypass.

A 61-year-old woman visited us with recent onset right-side weakness. Magnetic resonance imaging showed ischemic changes at the left internal border zone due to occlusive disease affecting the left proximal internal carotid artery. Prompt oral dual antiplatelet therapy and intravenous fluid were administered with subsequent induced hypertension and without reperfusion therapy. Although the hemiparesis was improved, she complained of a new-onset transient left-side monocular visual loss. Fluorescein angiography confirmed delayed perfusion in the left eye. We performed extracranial-intracranial bypass for flow augmentation. After bypass, the amaurosis fugax resolved. Follow-up retinal fluorescein angiography also showed improved retinal perfusion.

P2Y12 Reaction Units Threshold for Implementing Modified Antiplatelet Preparation in Coil Embolization of Unruptured Aneurysms: A Prospective Validation Study.

Purpose To identify and apply an optimized P2Y12 reaction units (PRU) threshold for implementing modified antiplatelet preparation to prevent thromboembolic events in patients nonresponsive to clopidogrel (clopidogrel nonresponders) undergoing coil embolization of unruptured aneurysms and to evaluate the clinical validity. Materials and Methods The optimal PRU threshold for prediction of thromboembolic events was determined with the Youden index in post hoc analysis of a previous, prospectively enrolled cohort of 165 patients in whom the antiplatelet regimen was not modified. This optimal PRU threshold was used to define clopidogrel nonresponders in a prospective validation study of 244 patients. Standard preparation (aspirin, clopidogrel) was maintained for 126 patients responsive to clopidogrel (clopidogrel responders, 51.6%), and modified preparation (aspirin, prasugrel) was prescribed prior to embolization for 118 clopidogrel nonresponders (48.4%). Fifty-seven clopidogrel nonresponders from the previous cohort who did not receive the modified preparation were included as a historical control group. Thromboembolic and bleeding events were compared among groups by using logistic regression analysis. Results Post hoc analysis from the previous cohort yielded PRU of at least 220 as the optimal threshold for modified preparation selection. The thromboembolic event rate of the clopidogrel responders (one of 126 [0.8%]) was lower than that of the historical control group that received standard preparation (seven of 57 patients [12.3%]; adjusted risk difference [RD], -10.1%; 95% confidence interval [CI]: -18.5, -1.7; P = .015) and was similar to that of clopidogrel nonresponders who received modified preparation (one of 118 [0.8%]; adjusted RD, -0.5%; 95% CI: -3.1, 2.1; P = .001 for noninferiority; P = .699 for superiority). Bleeding event rates did not differ among groups (four of 126 clopidogrel responders [3.2%] vs four of 57 clopidogrel nonresponders that received standard preparation [7.0%] [adjusted RD, -4.5%; 95% CI: -11.1, 3.4; P = .228] vs five of 118 clopidogrel nonresponders that received modified preparation [4.2%] [adjusted RD, -0.6%; 95% CI: -5.8, 4.2; P = .813]). Conclusion Patients undergoing coil embolization of unruptured aneurysms, regardless of clopidogrel responsiveness, had low thromboembolic risk when using PRU of at least 220 as the threshold for implementing modified antiplatelet preparation with prasugrel. © RSNA, 2016 Online supplemental material is available for this article.

Impact of the Penumbral Pattern on Clinical Outcome in Patients with Successful Endovascular Revascularization.

BACKGROUND: In patients with acute ischemic stroke, the impact of penumbral patterns on clinical outcomes after endovascular treatment (EVT) remains controversial. We aimed to establish whether penumbral patterns are associated with clinical outcome after successful recanalization with EVT while adjusting for onset to revascularization time. MATERIALS AND METHODS: Using a web-based, multicenter, prospective stroke registry database, we identified patients with acute ischemic stroke who underwent perfusion and diffusion magnetic resonance imaging (MRI) before EVT, had anterior circulation stroke, received EVT within 12 hours of symptom onset, and had successful revascularization confirmed during EVT. Based on pretreatment MRI, patients were stratified as having a favorable or nonfavorable penumbral pattern. Onset to revascularization time was dichotomized by median value. Primary outcome was functional independence (modified Rankin Scale score ≤2) at 90 days. FINDINGS: Among 121 eligible patients from three university hospitals, 104 (86.0%) had a favorable penumbral pattern, and the median time to revascularization was 271 minutes (interquartile range, 196-371). The functionally independent patient proportion was higher in those with a favorable penumbral pattern than in those without (53.8% versus 5.9%; P <.001), but was not different between early and late revascularization groups (49.2% versus 45.0%; P = .65). The favorable penumbral pattern was associated with functional independence after adjusting confounders (odds ratio, 23.25; 95% confidence interval: 1.58-341.99; P = .02). Time to revascularization did not modify the association (P for interaction, .53). CONCLUSION: A favorable penumbral pattern is associated with improved functional independence in patients with endovascular revascularization, and the association was not time-dependent.

Major recanalization occurs more often in young patients after unruptured aneurysm coil embolization.

BACKGROUND: The recanalization rate after coil embolization of unruptured aneurysms was compared between young and old age groups. METHODS: From May 2003 to December 2010, 636 patients with 715 saccular unruptured intracranial aneurysms (UIA) underwent endovascular coiling and were followed for at least 6 months. For comparative analysis, patients were categorized into two groups according to age 40: 42 patients with 46 aneurysms who were 40 years or younger (young age group) and 594 patients with 669 aneurysms who were older than 40 years (old age group). Angiographic and clinical outcomes including recanalization rates were compared. RESULTS: Angiographically, class 1 or 2 occlusion according to the Raymond-Roy Occlusion Classification system was achieved in 89.2 % of the patients (91.3 % in the young age group and 89.1 % in the old age group, p = 0.74). Procedure-related complication rate was 2.2 % and 3.4 % in the young and the old age group (p = 0.16), respectively. The mean follow-up duration was 30.51 ± 18.59 months. Major recanalization occurred in seven aneurysms (15.2 %) in the young age group and in 44 aneurysms (6.6 %) in the old age group (p = 0.03). Retreatment was performed in seven patients (15.2 %) in the young age group and in 35 patients (5.2 %) in the old age group (p = 0.01). CONCLUSIONS: The present study showed that the technical feasibility and safety of endovascular coiling for UIA did not differ between the two age groups. However, the major recanalization rate was higher in the young age group.

Recanalization Rate and Clinical Outcome in Acute Carotid-T Occlusion.

BACKGROUND: Acute carotid-T occlusion results in both low recanalization rates and poor outcomes. We investigated clinical outcomes and recanalization in a rare case of thrombolytic therapy. METHODS: A consecutive series of patients with acute carotid-T occlusion who were treated with either bridging intravenous (IV) plus intra-arterial (IA) thrombolysis or IA alone were analyzed. Complete recanalization was defined as a thrombolysis in cerebral infarction (TICI) grade of 3. A favorable outcome was defined as a modified Rankin Scale (mRS) score of ≤2. RESULTS: Of the 40 patients, 6 (15%) had favorable outcomes, and 34 (85%) had poor outcomes. Favorable outcomes were significantly associated with a lower National Institutes of Health Stroke Scale (NIHSS) score after revascularization treatment and higher rates of complete recanalization (p < 0.01, p < 0.024, respectively). Complete recanalization was achieved in all patients with favorable clinical outcomes and 5 (83%) patients had received combined IV/IA thrombolysis (p = 0.381). CONCLUSIONS: The results suggest that complete recanalization for acute carotid-T occlusion improves clinical outcomes. In that regard, bridging IV/IA thrombolysis may be more efficacious than IA alone.

Early carotid artery stenting for symptomatic carotid artery stenosis.

BACKGROUND: The aim of present study was to assess safety and efficacy of early carotid artery stent (CAS) in patients with symptomatic carotid artery stenosis compared with delayed CAS. METHODS: This retrospective study was approved by the institutional review board, and the requirement to obtain written informed consent was waived. Outcomes of 206 patients with symptomatic carotid stenosis who were treated by CAS were analyzed. According to CAS timing from last symptom, patients were divided into early (within 2 weeks, 74 [35.0 %]) and delayed (after 2 weeks, 112 [64.1 %]) group by CAS timing from the last symptom. Procedural complication and early (≤30 days of CAS) event (ipsilateral stroke or any death) for safety, and late (31 days to 1 year of CAS) event for efficacy of CAS preventing further stroke were evaluated. The two groups were compared using Cox proportional hazard analysis. RESULTS: No difference was found in procedural complication between the groups (early 2 [2.7 %] vs. delayed group 7 [5.3 %], hazard ratio [HR] 0.61, 95 % confidence interval [CI] 0.123-2.979, p = 0.537). In the early group, however, early event developed more frequently than in the late group (9 [12.2 %] vs. 1 [0.8 %], HR 16.05, 95 % CI 1.991-129.438, p = 0.009). The late event rate showed no difference between the two groups (4 [5.4 %] vs. 4 [3.0 %], HR 2.09, 95 % CI 0.484-8.989, p = 0.324). CONCLUSIONS: Early CAS is not safe during periprocedural period, compared with late CAS. In CAS for symptomatic carotid stenosis, delayed CAS should be considered.

Morphology and related hemodynamics of the internal carotid arteries of moyamoya patients.

BACKGROUND: Morphological studies investigating the intracranial-extradural internal carotid artery with moyamoya disease have not been reported. We designed this case-control study to investigate the morphological differences of the internal carotid artery with moyamoya disease, and to clarify the contributions of these differences to the resultant fluid dynamics. METHODS: Patients with moyamoya disease and normal controls were assigned to each group. The vascular tortuosity of internal carotid artery was measured with three-dimensional rendering using magnetic resonance angiography. By computational fluid dynamics, hemodynamic characteristics were simulated and compared between two groups. RESULTS: Distances were measured from the carotid canal to the siphon. A shorter actual distance was observed in the moyamoya group (p = 0.0170). Vascular tortuosity was significantly low in moyamoya patients showing lower curvature angles in the petrous and intra-cavernous segments (p = 0.0012). Less blood flowed (p < 0.0001) through the narrower internal carotid artery (p < 0.0001) in the moyamoya group at the carotid canal level. The blood flow velocities were not significantly different (p = 0.2332). Faster blood flow and higher wall shear stress in the internal carotid artery bifurcation were verified with computational fluid dynamics. CONCLUSIONS: Significant morphological differences were confirmed to exist in the intracranial-extradural internal carotid artery of moyamoya patients. These differences might influence the hemodynamics around the bifurcation of the internal carotid artery.

Long-term outcomes after combined revascularization surgery in adult moyamoya disease.

BACKGROUND AND PURPOSE: The surgical outcomes of adult moyamoya disease are rarely reported. We aimed to evaluate the long-term outcomes of combined revascularization surgery in patients with adult moyamoya disease. METHODS: Combined revascularization surgery consisting of superficial temporal artery-middle cerebral artery anastomosis with encephalodurogaleosynangiosis was performed on 77 hemispheres in 60 patients. Clinical, angiographic, and hemodynamic states were evaluated retrospectively using quantitative methods preoperatively and postoperatively in the short-term (≈6 months) and long-term (≈5 years) periods. The mean clinical follow-up duration was 71.0±10.1 months (range, 60-104 months). RESULTS: Clinical status improved until 6 months after surgery and remained stable thereafter, as assessed by the Karnofsky Performance Scale and modified Rankin Scale. The revascularization area relative to supratentorial area significantly increased in the long-term period compared with that in the short-term period (54.8% versus 44.2%; P<0.001). Cerebral blood flow in the territory of the middle cerebral artery improved in the short-term period compared with that in the preoperative period (68.7 versus 59.1; considering blood flow of the pons as 50; P<0.001) and thereafter became stable (65.5 in the long term; P=0.219). The annual risks of symptomatic hemorrhage and infarction were 0.4% and 0.2%, respectively, in the operated hemispheres. CONCLUSIONS: Combined revascularization surgery resulted in satisfactory long-term improvement in clinical, angiographic, and hemodynamic states and prevention of recurrent stroke.

A retrospective analysis on the natural history of incidental small paraclinoid unruptured aneurysm.

OBJECTIVE: The optimal consensus concerning treatment of incidental small paraclinoid unruptured intracranial aneurysms (UIAs) remains controversial. The aim of this retrospective study was to reveal the natural history of small paraclinoid UIAs with the goal of informing the treatment plan. METHODS: 524 patients harbouring 568 paraclinoid UIAs (≤5 mm) were retrospectively evaluated during the mean follow-up of 35.4 months. The aneurysms were divided into two groups with respect to arterial branch: related (ophthalmic and superior hypophyseal artery), and non-related. Medical records were reviewed concerning multiple variables, such as sex, age, hypertension (HTN), diabetes mellitus, smoking and aneurysmal factors (size, arterial relationship, multiplicity and the occurrence of rupture and growth). The cumulative risk and the risk factors of aneurysmal rupture and growth were analysed. RESULTS: Two aneurysmal (0.35%) ruptures and 17 growths (3.0%) were observed during the follow-up of 1675.5 aneurysm-years with an annual rupture of 0.12% and an annual growth of 1.01%. The cumulative survival without aneurysmal growth reached a significant difference in aneurysms ≥4 mm (p=0.001), HTN (p=0.002), and arterial branch-related location (p=0.001). Multivariate analysis disclosed that aneurysm ≥4 mm (HR, 4.41; p=0.003), HTN (HR, 5.74; p=0.003), arterial branch-related location (HR, 6.04; p=0.002), and multiplicity (HR, 0.27; p=0.042) were significant predictive factors for aneurysm growth. CONCLUSIONS: Although incidental small paraclinoid UIAs have a relatively lower rupture and growth risk, patients with high-risk factors, including aneurysm ≥4 mm, HTN, arterial branch-related aneurysms, and multiple aneurysms must be monitored closely. The limitation of the retrospective nature of this study should be taken into consideration.

A risk factor analysis of prospective symptomatic haemorrhage in adult patients with cerebral cavernous malformation.

OBJECTIVE: The purpose of this study was to assess the risk factors of prospective symptomatic haemorrhage in a large series of adult patients with cerebral cavernous malformation (CM). METHODS: Three hundred twenty-six patients >18 years of age with 410 CMs were evaluated retrospectively. Symptomatic haemorrhage was defined as new clinical symptoms with radiographic features of haemorrhage. Clinical data and the characteristics of CM were analysed. MR appearance was divided into three groups according to Zabramski's classification. RESULTS: The overall haemorrhage rate of CM was 4.46% per lesion-year. The overall annual haemorrhage rate according to MR appearance was as follows: type I, 9.47%; type II, 4.74%; and type III, 1.43%. A multivariate analysis revealed that prior symptomatic haemorrhage (p<0.001) and MR appearance (p<0.001) were statistically significant. After multiple comparisons, type I (p<0.001) and type II (p=0.016) showed higher haemorrhage risk than type III. However, no significant difference in haemorrhage rate was observed between type I and type II (p=0.105). Other variables including female gender, age, location, multiplicity, hypertension, size and associated venous angioma were not significant. The haemorrhage rates based on risk factors were estimated at 3 years as follows: 33.77% in patients with prior haemorrhage versus 7.54% in patients without prior haemorrhage (p<0.001); type I, 27.62% vs type II, 15.44% vs type III, 5.38% (p<0.001). CONCLUSIONS: Prior symptomatic haemorrhage and MR appearance could be related to prospective symptomatic CM haemorrhage in adults. A prospective multicentre observational study is necessary to confirm our results.

Expression of cellular retinoic acid-binding protein-I (CRABP-I) in the cerebrospinal fluid of adult onset moyamoya disease and its association with clinical presentation and postoperative haemodynamic change.

OBJECTIVE: The elevation of cellular retinoic acid-binding protein-I (CRABP-I) has been suggested as a candidate in the pathogenesis of paediatric moyamoya disease (MMD). However, few studies have addressed CRABP-I in adult onset MMD. The aim of this study was to examine the expression of CRABP-I in the cerebrospinal fluid (CSF) of adult onset MMD, and to evaluate its association with clinical presentation and postoperative haemodynamic change. METHODS: This study examined the CSF from 103 patients: bilateral MMD, n=58 (56.3%); unilateral MMD, n=19 (18.4%); atherosclerotic cerebrovascular disease (ACVD), n=21 (20.4%); and control group, n=5 (4.9%). The intensity of CRABP-I was confirmed by western blotting and expressed as the median (25th-75th percentile). The differences in CRABP-I expression according to disease entity (unilateral MMD vs bilateral MMD vs ACVD), initial presenting symptoms (haemorrhage vs ischaemia) and postoperative haemodynamic change (vascular reserve in single photon emission CT and basal collateral vessels in digital subtraction angiography) were analysed. RESULTS: CRABP-I intensities in bilateral MMD (1.45(0.86-2.52)) were significantly higher than in unilateral MMD (0.91(0.78-1.20)) (p=0.044) or ACVD (0.85(0.66-1.11)) (p=0.004). No significant differences were noted based on the initial presenting symptoms (p=0.687). CRABP-I was not associated with improvement in vascular reserve (p=0.327), but with decrease in basal collateral vessels (p=0.023) postoperatively. CONCLUSIONS: Higher CRABP-I in the CSF can be associated with typical bilateral MMD pathogenesis in adults. Additionally, postoperative basal collateral change may be related to the degree of CRABP-I expression.

Endovascular internal carotid artery trapping for ruptured blood blister-like aneurysms: long-term results from a single centre.

INTRODUCTION: Endovascular internal carotid artery (ICA) trapping was performed to treat ruptured blood blister-like aneurysms (BBAs). The aim of this study was to evaluate the procedural risks and long-term follow-up results. METHODS: The records of 11 consecutive patients with BBAs who underwent endovascular ICA trapping between 2005 and 2010 were reviewed. Clinical outcomes were assessed with modified Rankin Scale (mRS) scores. RESULTS: Endovascular ICA trapping was performed in 11 patients as either the primary treatment (7 patients) or the secondary treatment (4 patients) after the patient underwent other treatments. Three patients underwent superficial temporal artery (STA)-middle cerebral artery (MCA) bypass when balloon test occlusion (BTO) revealed inadequate collateral circulation. In the primary ICA trapping group (seven patients), six patients had good outcomes (mRS 0 in five, mRS 1 in one), and one patient had a poor outcome (mRS 6: dead). In the secondary ICA trapping group (four patients), two patients had good outcomes (mRS 0), and two patients had poor outcomes (mRS 4, 5). All ten of the surviving patients were clinically stable during the follow-up period (mean 39 months). A radiological follow-up of nine patients (mean 22 months) demonstrated stable occlusion, with the exception of one reopening of the ICA because of coil migration. Perfusion studies of nine patients (mean: 23 months) demonstrated no perfusion decrease. CONCLUSION: Endovascular ICA trapping is an effective and durable treatment for BBAs.

Contralateral progression and its risk factor in surgically treated unilateral adult moyamoya disease with a review of pertinent literature.

BACKGROUND: The fate of the contralateral unaffected side of the surgically treated unilateral moyamoya disease (MMD) in adults has not been well described due to the limited number of cases and the heterogeneous ages and treatment methods. The aim of this study was to evaluate the contralateral angiographic progression rate and its risk factors in homogeneous adult MMD patients who underwent surgical revascularization, with a review of pertinent literature. METHODS: Forty-one surgically treated unilateral MMD patients were retrospectively evaluated. We reviewed medical and radiological records including data on gender, age, hypertension (HTN), smoking, familial MMD, presenting symptom, surgical method, Suzuki stage, and contralateral progression. Then, we conducted univariate and multivariate analyses to determine risk factors. RESULTS: Six of the 41 cases (14.6%) exhibited contralateral progression during the mean follow-up of 34 months. Four of those six patients (66.7%) were asymptomatic. Additional revascularization surgery was performed in the two symptomatic patients. The presence of a contralateral angiographic abnormality on initial angiography was a statistically significant risk factor for progression (OR, 49.00; p = 0.04). Younger age at diagnosis (32.7 ± 7.8 years in progression group vs. 42.5 ± 10.3 years in non-progression group, p = 0.046) was statistically significant in the univariate analysis, but age was not a significant factor in the multivariate analysis (p = 0.82). Other variables, such as gender (p = 0.13), HTN (p = 0.24), smoking (p = 0.47), and familial MMD (p = 0.20), did not show statistical significance. CONCLUSIONS: The presence of a contralateral angiographic abnormality on initial angiography was a significant risk factor for progression in surgically treated unilateral adult MMD. Consequently, patients with contralateral abnormalities should be monitored closely.

Relationship between in-stent restenosis following carotid artery stenting and platelet reactivity to clopidogrel.

OBJECTIVE: To analyze the relationship between in-stent restenosis (ISR) following carotid artery stenting (CAS) and platelet clopidogrel reactivity confirmed by the P2Y12 reaction unit (PRU) and inhibition rate (IR). METHODS: We retrospectively analyzed 171 patients who underwent CAS with extracranial carotid stenosis from January 2016 to December 2019. Dual antiplatelet therapy with 100 mg aspirin and 75 mg clopidogrel was started ≥5 days before CAS. Clopidogrel resistance was measured with the PRU and IR the day before CAS. The ISR degree was classified into R1, R2, and R3 (moderate to severe luminal stenosis of ≥50% or occlusion) by carotid CT angiography after 24-30 months. The degree of quantitative association between platelet reactivity and ISR R3 was determined by the receiver operating characteristic curve method. The optimal cut-off values of PRU and IR were derived using the maximum Youden index. RESULTS: There were 33 R3 degrees of ISR (19.3%) and nine ipsilateral ischemic strokes (5.3%). The PRU and IR were different between R1+R2 degrees (176.4±50.1, 27.5±18.7%) and R3 degree (247.5±55.0, 10.3±13.4%) (P<0.001). The areas under the curves of PRU and IR were 0.841 and 0.781, and the optimal cut-off values were 220.0 and 14.5%, respectively. Multivariate logistic regression analysis showed that PRU ≥220 and IR ≤14.5% were significant predictive factors for ISR R3 (P<0.001 and P=0.017, respectively). ISR R3 was independently associated with ipsilateral ischemic stroke after CAS (P=0.012). CONCLUSIONS: High PRU (≥220) and low IR (≤14.5%) are related to ISR R3 following CAS, which may cause ipsilateral ischemic stroke.