Factors related to microcatheter passage through the trans-cell approach using a low-profile visualized intraluminal support device: an in-vitro study.

BACKGROUND AND PURPOSE: The trans-cell approach using a low-profile visualized intraluminal support (LVIS) device is sometimes used for aneurysm coil embolization. However, factors related to microcatheter passage remain uninvestigated. We aimed to examine in-vitro factors related to microcatheter passage using the trans-cell approach with an LVIS. METHODS: Silicone vessel models (inner diameter, 4 mm) were created with different bend segments and a 4-mm hole assuming an aneurysm neck on the side of the greater curvature. The LVIS Blue (4.5 × 32 mm) was deployed at the bend segment, and passability on the trans-cell surface was evaluated by passing the microcatheter along the micro guidewire. A total of 800 passage experiments were performed using two types of microcatheter, ten types of silicone vessel, four cell widths, five cells with the same LVIS device, and two micro guidewire directions in the aneurysm. RESULTS: The Headway Duo microcatheter (35.5%, 142/400) tended to have better passability compared with the Headway 17 microcatheter (29.3%, 117/400) (p = 0.070). As the cell width and angle between the trans-cell surface and microcatheter direction increased, passability significantly increased (p = 0.027 and p < 0.001, respectively). There was no significant difference in passability when the micro guidewire was directed to the proximal side versus the distal side (p = 0.45). CONCLUSIONS: A large cell width and an obtuse angle between the trans-cell surface and microcatheter direction facilitated good passability. Although statistically marginal, microcatheters with small ledges and small tips had relatively good passability.

Flexible endoscopically assisted evacuation of acute and subacute subdural hematoma through a small craniotomy: preliminary results.

BACKGROUND: The first choice to treat acute subdural hematoma (SDH) is a large craniotomy under general anesthesia. However, increasing age or comorbid burden of the patients may render invasive treatment strategy inappropriate. These medically frail patients with SDH may benefit from a combination of small craniotomy and endoscopic hematoma removal, which is less invasive and even available under local anesthesia. Although hematoma evacuation with a rigid endoscope for acute or subacute SDHs has been reported in the literature, use of a flexible endoscope may have distinct advantages. In this article, we attempted to clarify the utility of small craniotomy evacuation with a flexible endoscope for acute and subacute SDH in the elderly patients. METHOD: Between November 2013 and September 2016, a total of 17 patients with acute SDH (15 patients), subacute SDH (1 patient), or acute aggravation of chronic SDH (1 patient) underwent hematoma evacuation with a flexible endoscope at our hospital and were enrolled in this retrospective study. Either under local or general anesthesia, the SDH was removed with a flexible suction tube with the aid of the flexible endoscope through the small craniotomy (3 × 4 cm). Hematoma evacuation rate, improvement of clinical symptoms, and procedure-related complications were evaluated. RESULTS: Hematoma evacuation rate was satisfactory, and statistically significant clinical improvement was observed in postoperative Glasgow Coma Scale in all cases compared to the preoperative assessment. No procedure-related hemorrhagic complications were observed. CONCLUSIONS: The results reported here suggest that small craniotomy evacuation with a flexible endoscope is a safe, effective, and minimally invasive treatment for acute and subacute SDH in selected cases.

Asymptomatic Carotid T1-High-Intense Plaque as a Risk Factor for a Subsequent Cerebrovascular Ischemic Event.

BACKGROUND: Intraplaque hemorrhage, detected as a high-signal intensity on carotid MRI, is also strongly associated with ischemic events in symptomatic patients. However, in asymptomatic patients, the relationship of the T1-high intense plaque and the subsequent stroke is not clear. The aim of this study is to test the hypothesis that asymptomatic carotid T1-high intense plaque is a risk factor for a subsequent cerebrovascular ischemic event. METHODS: Of the 1,353 consecutive patients, who underwent head and carotid MRI as part of their annual medical check-up, the imaging quality of 13 was poor and 150 did not present for follow-up examination, thus leaving 1,190 subjects for evaluation. Of the 1,190 patients, 96 patients had findings of high-signal intensity on carotid MRI and 1,094 patients did not. Cerebrovascular events were retrospectively evaluated. RESULTS: During a mean follow-up period of 53 months, 4 patients with high-signal intensities on carotid MRI (4%) and 3 with no findings (0.3%) had a cerebrovascular ischemic event, with the occurrences significantly higher in the high-signal-intensity group. (p < 0.01) Cox regression analysis indicated that the presence of the high-intense plaque on carotid MRI (hazard ratio [HR] 4.2; 95% CI 1.0-17.1; p = 0.04), age (HR 1.1; 95% CI 1.0-1.2; p = 0.003), and diabetes mellitus (HR 7.2; 95% CI 1.8-27.4; p = 0.004) were associated with the occurrence of subsequent ischemic cerebrovascular events. CONCLUSIONS: Asymptomatic carotid T1-high-intense plaque might be a potential high-risk factor for a subsequent cerebrovascular ischemic event.

Histological Examination of Trousseau Syndrome-Related Thrombus Retrieved Through Acute Endovascular Thrombectomy: Report of 2 Cases.

The mechanism of thrombus formation in Trousseau syndrome remains unclear. The purpose of this study was to investigate specific pathological findings of the thrombi in Trousseau syndrome. The authors report on 2 cases of thrombi in Trousseau syndrome from large cerebral vessels removed by endovascular therapy and compared with thrombi in atherosclerosis or cardiac embolism. The first patient, a 67-year-old man, was transferred to our hospital for sudden onset consciousness disturbance and tetraparesis. He had been diagnosed with stage IV lung cancer. The magnetic resonance (MR) angiography demonstrated basilar artery occlusion. An endovascular thrombectomy was performed. The second patient, an 84-year-old woman, was transferred to our hospital for sudden onset motor aphasia and right-sided motor weakness. She has a history of stage IV pancreatic body cancer. The MR angiography demonstrated left middle cerebral artery occlusion. An endovascular thrombectomy was performed for the floating thrombus. Macroscopic findings of retrieved thrombi were observed immediately after thrombectomy. The thrombi in Trousseau syndrome were white in color and solid against manual compression, whereas thrombi from other causes were red and fragile. In terms of microscopic findings, the thrombi in Trousseau syndrome mainly contained fibrin. On the other hand, thrombi associated with atherosclerosis or cardiac embolism had smaller area of fibrin with a considerable amount of red and white blood cells. The thrombi in Trousseau syndrome, which caused occlusion of large cerebral vessel, almost exclusively consisted of fibrin.

Reflux of Anterior Spinal Artery Predicts Recurrent Posterior Circulation Stroke in Bilateral Vertebral Artery Disease.

BACKGROUNDS AND PURPOSE: Predictive value of reflux of anterior spinal artery for recurrent posterior circulation ischemia in bilateral vertebral arteries steno-occlusive disease was evaluated. METHODS: We retrospectively reviewed 55 patients with symptomatic posterior circulation stroke caused by bilateral stenotic (>70%) lesions of the vertebral artery. We investigated any correlation of clinical and angiographic characteristics including collateral flow patterns, with recurrent stroke. Risk factors for poor 3-month functional outcome were also evaluated. RESULTS: Recurrent posterior circulation stroke was observed in 15 (27.3%) patients. Multivariable analysis using Cox proportional hazards model showed anterior spinal artery reflux as a significant risk factor for stroke recurrence (adjusted hazard ratio, 19.3 [95% confidence interval, 5.35-69.9]; P<0.001). Anterior spinal artery reflux was also correlated with poor functional outcome (modified Rankin Scale score, 3-6; adjusted odds ratio, 7.41 [95% confidence interval, 1.24-44.4]; P=0.028). CONCLUSIONS: In patients with symptomatic bilateral vertebral artery occlusive disease, anterior spinal artery reflux predicted recurrent posterior circulation stroke and poor functional outcome.

[Cost Comparison of Carotid Endarterectomy versus Carotid Stenting in Japan].

Carotid artery stenting (CAS) has been covered by the health insurance system in Japan since 2008. There have been few studies concerning medical costs and charges for patients who received CEA or CAS in Japan. The aim of this study was to elucidate the difference in the costs between the patients who received CEA and those who received CAS in Japan. Between 2010 and 2011, 19 patients who received CEA and 20 patients who received CAS were retrospectively reviewed. Age, sex, symptomatic/asymptomatic, emergent/scheduled, length of stay, outcome, cost for the procedure (professional fee), supply for the operation, the total medical service fee, and copayment of the patients was compared between the two treatment groups. No significant difference was detected between the two groups except for the supply of the operation and the total medical service fee (CEA:mean 1,565,580 yen vs CAS 2,758,360 yen, p=0.0001). On the other hand, no significant difference was obtained in the copayment of the patients (CEA 71,895 yen, CAS 72,458 yen). Even when limited to the scheduled cases, similar results were obtained. There is a monthly copayment limit in the health insurance system in Japan, which results in a reasonable charge for patients who received CAS, despite the fact that the rest of the fee including high costs for the supplies was paid by the company and the nation. To reduce the medical costs, Japanese have to be aware of the high costs in CAS, most of which is due to the supplies.

Hemodynamic Change due to Vessel Straightening Immediately after LVIS Jr. Deployment for an Anterior Communicating Artery Aneurysm.

Objective: Stent-assisted coil embolization for cerebral aneurysms may lead to straightening of the parent vessel. However, detailed reports documenting the hemodynamic change in bifurcation type aneurysms due to straightening of the parent vessel immediately after stent deployment are scarce. Case Presentation: A 48-year-old woman with a history of polycystic kidney disease underwent aneurysm neck clipping with left frontotemporal craniotomy for a ruptured bifurcation-type anterior communicating artery (AComA) aneurysm. Angiography 18 days after clipping showed a recurrent AComA aneurysm, for which stent-assisted coil embolization was performed. Straightening of the parent vessel immediately after deployment of a low-profile visualized intraluminal support junior (LVIS Jr.) stent from the AComA to the A1 segment of the right anterior cerebral artery was confirmed by working projection angiography. The aneurysm was easily embolized with coils with the support of the stent covering the aneurysm neck. The embolization was finished with a slight dome filling of the aneurysm. The parent vessel angle in 3D angiography changed from 90° before stent deployment to 160° immediately after stent deployment. Angiography 2 months after embolization showed the aneurysm with a complete occlusion and the parent vessel angle of 170° in a 3D image. Conclusion: The hemodynamic change in a bifurcation-type AComA aneurysm due to straightening of the parent vessel immediately after the LVIS Jr. stent deployment led to the covering of the aneurysm neck, resulting in good coil embolization, to which the vessel mobility and the stenting method may have contributed.

Inferior Epigastric Artery Injury due to Femoral Venipuncture for Neuroendovascular Intervention: Two Cases Requiring Transcatheter Arterial Embolization.

Objective: Injury to the inferior epigastric artery (IEA) caused by femoral puncture may lead to retroperitoneal hematoma. We report on two cases of IEA injury due to femoral venipuncture for neuroendovascular intervention that resulted in hemorrhagic shock and required transcatheter arterial embolization. Case Presentations: A 67-year-old woman and a 71-year-old man receiving dual antiplatelet therapy sustained injury to a branch of the IEA in the process of right femoral venipuncture for neuroendovascular intervention. In both cases, stent placement in the intracranial artery was accomplished as intended with systemic heparinization throughout the procedure; however, the patients became hypotensive during the procedure, and contrast-enhanced CT scans taken after the stenting revealed extravasation of contrast from the IEA and retroperitoneal hematoma. Transcatheter arterial embolization of the bleeding branch of the IEA was performed with the left femoral approach, and subsequent angiography confirmed the disappearance of the extravasation of contrast. Conclusion: Femoral venipuncture for neuroendovascular intervention in patients receiving antithrombotic agents may cause IEA injury requiring transcatheter arterial embolization. The risk of IEA injury may be reduced by using the femoral head as a reference, performing ultrasound-guided puncture, and confirming the course of the IEA by femoral angiography before venipuncture.

Gradual dilatation of an occluded transverse sinus associated with dural arteriovenous fistula after balloon angioplasty with sinus packing: A case report.

BACKGROUND: There is no consensus as to whether balloon angioplasty alone or stent placement is effective for sinus occlusion associated with dural arteriovenous fistula (DAVF). Herein, we first report a case of transverse sinus occlusion associated with DAVF in which gradual sinus dilatation was observed after balloon angioplasty with embolization of the affected sinus with shunt flow. CASE PRESENTATION: A 69-year-old man presented with executive dysfunction. Magnetic resonance imaging revealed left transverse sinus-sigmoid sinus DAVF with occlusion of the left jugular vein and right transverse sinus. Before endovascular treatment, the patient had symptomatic epilepsy and subarachnoid hemorrhage. Retrograde leptomeningeal venous drainage disappeared with packing of the left transverse sinus-sigmoid sinus. Subsequently, balloon angioplasty of the right occluded transverse sinus was performed to maintain the normal venous drainage and remaining shunt outflow. Dilatation of the right transverse sinus was poor immediately after surgery. However, angiography after 10 days and 6 months revealed gradual dilatation of the right transverse sinus. CONCLUSION: Sinus occlusion, which is thought to be caused by sinus hypertension associated with DAVF rather than chronic organized thrombosis or thrombophilia, may dilate over time after balloon angioplasty and shunt flow reduction if occluded sinus is necessary for facilitating normal venous drainage.

Low-profile visualized intraluminal support Blue stenting within a Neuroform Atlas stent for a large wide-necked aneurysm: A case report and a bench-top experiment.

Low-profile visualized intraluminal support deployment in an Enterprise has been reported; however, that in an Atlas has yet to be in detail. Enterprise has a closed-cell design, while Atlas has an open-cell design. We detail here a case of a large wide-necked aneurysm treated by coil embolization with low-profile visualized intraluminal support Blue deployment within a Neuroform Atlas and a bench-top experiment using a silicon tube to test low-profile visualized intraluminal support, Atlas, Enterprise, and their combinations. A better low-profile visualized intraluminal support expansion was achieved by simultaneously pushing the wire and the system within the Atlas placed at the aneurysm neck, which resulted in an increased metal coverage of the aneurysm neck and a shorter transition zone with low metal coverage at both ends of the aneurysm neck. This technique may enable a high metal coverage by low-profile visualized intraluminal support expansion without restriction by the Atlas and contribute to aneurysm occlusion by increasing the flow-diverting effect.

Association of plasma D-dimer level with thromboembolic events after endovascular coil treatment of ruptured cerebral aneurysms.

OBJECTIVEAlthough endovascular therapy is favored for acutely ruptured intracranial aneurysms, hematological factors associated with acute subarachnoid hemorrhage (SAH) may predispose to procedure-related ischemic complications. The aim of this study was to evaluate whether an elevated level of plasma D-dimer, a parameter of hypercoagulation in patients with acute SAH, is correlated with increased incidence of thromboembolic events during endovascular coiling of ruptured aneurysms.METHODSThe authors analyzed data from 103 cases of acutely ruptured aneurysms (in 103 patients) treated with endovascular coil embolization at a single institution. Factors associated with elevated D-dimer level on admission were identified. The authors also evaluated whether D-dimer elevation was independently correlated with increased incidence of perioperative thromboembolic events.RESULTSAn elevated D-dimer concentration (≥ 1.0 µg/ml) on admission was observed in 70 (68.0%) of 103 patients. Increasing age (p < 0.001, Student t-test) and poor initial neurological grade representing World Federation of Neurosurgical Societies (WFNS) grade IV or V (p = 0.0018, chi-square test) were significantly associated with D-dimer elevation. Symptomatic thromboembolic events occurred in 11 cases (10.7%). Elevated D-dimer levels on admission (OR 1.34, 95% CI 1.10-1.62, p = 0.0029) independently carried a higher risk of thromboembolic events after adjustment for potential angiographic confounders, including wide neck of the aneurysm and large aneurysm size.CONCLUSIONSElevated D-dimer levels on admission of patients with acute SAH were significantly associated with increased incidence of thromboembolic events during endovascular coiling of ruptured aneurysms.

Effect of intrathecal milrinone injection via lumbar catheter on delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

OBJECTIVE Delayed cerebral ischemia (DCI) is an important complication after aneurysmal subarachnoid hemorrhage (aSAH). Although intrathecal milrinone injection via lumbar catheter to prevent DCI has been previously reported to be safe and feasible, its effectiveness remains unknown. The goal of this study was to evaluate whether intrathecal milrinone injection treatment after aSAH significantly reduced the incidence of DCI. METHODS The prospectively maintained aSAH database was used to identify patients treated between January 2010 and December 2015. The cohort included 274 patients, with group assignment based on treatment with intrathecal milrinone injection or not. A propensity score model was generated for each patient group, incorporating relevant patient variables. RESULTS After propensity score matching, 99 patients treated with intrathecal milrinone injection and 99 without treatment were matched on the basis of similarities in their demographic and clinical characteristics. There were significantly fewer DCI events (4% vs 14%, p = 0.024) in patients treated with intrathecal milrinone injection compared with those treated without it. However, there were no significant differences between the 2 groups with respect to their 90-day functional outcomes (46% vs 36%, p = 0.31). The likelihood of chronic secondary hydrocephalus, meningitis, and congestive heart failure as complications of intrathecal milrinone injection therapy was also similar between the groups. CONCLUSIONS In propensity score-matched groups, the intrathecal administration of milrinone via lumbar catheter showed significant reduction of DCI following aSAH, without an associated increase in complications.

Association of Perforator Infarction with Clinical Courses and Outcomes Following Surgical Clipping of Ruptured Anterior Communicating Artery Aneurysms.

BACKGROUND: Perforator infarction is a procedure-related complication of surgical clipping of ruptured anterior communicating artery (ACoA) aneurysms. Patients with perforator infarction may present with specific clinical features. The aim of this study was to elucidate incidence, risk factors, clinical course, and outcomes of perforator infarction following surgical clipping of ruptured ACoA aneurysms. METHODS: Retrospective analysis was performed of 104 patients from a single-center, observational cohort database who underwent surgical clipping for ruptured ACoA aneurysm. Risk factors of perforator infarction were identified. Correlation of perforator infarction with clinical course during hospitalization was investigated, focusing on dysfunction of hypothalamus and cerebral limbic system. We also evaluated any associations between perforator infarction and poor outcomes. RESULTS: Perforator infarction was observed in 24 (23.1%) patients. Use of temporary clip (P = 0.019, χ2 test) and intraoperative rupture (P < 0.001, χ2 test) were significantly associated with perforator infarction. Patients with perforator infarction had increased likelihood of hyponatremia (odds ratio 6.41 [95% confidence interval 2.27-18.1], P < 0.001) and insufficient oral intake (odds ratio 6.53 [95% confidence interval 1.80-23.7], P = 0.004) in the subacute stage of subarachnoid hemorrhage by multivariate analyses. Perforator infarction was an independent risk factor of poor functional outcomes at 3 months (modified Rankin Scale score 3-6; odds ratio 5.29 [95% confidence interval 1.62-17.2], P = 0.006). CONCLUSIONS: Perforator infarction following surgical clipping of ruptured ACoA aneurysms caused region-specific complications, including hyponatremia and insufficient oral intake, and was associated with poor functional outcomes.

Plasma D-dimer may predict poor functional outcomes through systemic complications after aneurysmal subarachnoid hemorrhage.

OBJECTIVE Plasma D-dimer levels elevate during acute stages of aneurysmal subarachnoid hemorrhage (SAH) and are associated with poor functional outcomes. However, the mechanism in which D-dimer elevation on admission affects functional outcomes remains unknown. The aim of this study is to clarify whether D-dimer levels on admission are correlated with systemic complications after aneurysmal SAH, and to investigate their additive predictive value on conventional risk factors for poor functional outcomes. METHODS A total of 187 patients with aneurysmal SAH were retrospectively analyzed from a single-center, observational cohort database. Correlations of plasma D-dimer levels on admission with patient characteristics, initial presentation, neurological complications, and systemic complications were identified. The authors also evaluated the additive value of D-dimer elevation on admission for poor functional outcomes by comparing predictive models with and without D-dimer. RESULTS D-dimer elevation on admission was associated with increasing age, female sex, and severity of SAH. Patients with higher D-dimer levels had increased likelihood of nosocomial infections (OR 1.22 [95% CI 1.07-1.39], p = 0.004), serum sodium disorders (OR 1.11 [95% CI 1.01-1.23], p = 0.033), and cardiopulmonary complications (OR 1.20 [95% CI 1.04-1.37], p = 0.01) on multivariable analysis. D-dimer elevation was an independent risk factor of poor functional outcome (modified Rankin Scale Score 3-6, OR 1.50 [95% CI 1.15-1.95], p = 0.003). A novel prediction model with D-dimer had significantly better discrimination ability for poor outcomes than conventional models without D-dimer. CONCLUSIONS Elevated D-dimer levels on admission were independently correlated with systemic complication, and had an additive value for outcome prediction on conventional risk factors after aneurysmal SAH.

Short-Term Results of Carotid Endarterectomy and Stenting After the Introduction of Carotid Magnetic Resonance Imaging: A Single-Institution Retrospective Study.

OBJECTIVE: Although carotid artery stenting (CAS) has been gaining popularity as an alternative to carotid endarterectomy (CEA), perioperative stroke rate following contemporary CAS remains significantly higher than stroke rate after CEA. The purpose of this study was to assess perioperative (within 30 days) therapeutic results in patients with carotid stenosis (CS) after introduction of preoperative carotid magnetic resonance imaging plaque evaluation in a single center performing both CEA and CAS. METHODS: Based on prospectively collected data for patients with CS who were scheduled for carotid revascularization, retrospective analysis was conducted of 295 consecutive patients with CS. An intervention was selected after consideration of periprocedural risks for both CEA and CAS. Concerning risk factors for CAS, results of magnetic resonance imaging plaque evaluation were emphasized with a view toward reducing embolic complications. RESULTS: CAS was performed in 114 patients, and CEA was performed in 181 patients. Comparing baseline characteristics of the 295 patients, age, T1 signal intensity of plaque, symptomatic CS, urgent intervention, and diabetes mellitus differed significantly between CAS and CEA groups. Among patients who underwent CAS, new hyperintense lesions on diffusion-weighted imaging were confirmed in 47 patients. New hyperintense lesions on diffusion-weighted imaging were recognized in 21.4% of patients who underwent CEA (n = 39), significantly less frequent than in patients who underwent CAS. CONCLUSIONS: The overall short-term outcome of CEA and CAS is acceptable. Preoperative carotid magnetic resonance imaging evaluation of plaque might contribute to low rates of ischemic complications in CAS.

Acute Compressive Myelopathy Caused by Spinal Subarachnoid Hemorrhage: A Combined Effect of Asymptomatic Cervical Spondylosis.

BACKGROUND: Patients with subarachnoid hemorrhage (SAH) by hemorrhagic arteriovenous fistulas (AVFs) usually presents with meningeal signs, including headache and nausea, and focal neurologic deficit is found in rare cases. In this article, we report a case of acute compressive cervical myelopathy caused by hemorrhagic AVF at the craniocervical junction. CASE DESCRIPTION: A 73-year-old woman was transferred to our hospital for sudden headache and subsequent left hemiparesis. Head computed tomography scan showed SAH exclusively in the posterior fossa, and catheter angiography revealed a perimedullary arteriovenous fistula at the craniocervical junction as a source of the SAH. Detailed neurologic examination showed the sensory disturbance of bilateral upper extremities and bladder and rectal disturbance, suggesting concurrent cervical myelopathy. Magnetic resonance imaging of the cervical spine showed disk herniation at the C4-5 level, spinal SAH deposition above the C4-5 level, and accompanying myelomalacia. No intramedullary hemorrhage was found. CONCLUSIONS: Spinal SAH alone rarely causes focal neurologic deficit. However, this case suggests spinal SAH can cause acute compressive myelopathy when complicated with preexisting spinal canal stenosis.

Carotid artery plaque assessment using quantitative expansive remodeling evaluation and MRI plaque signal intensity.

OBJECTIVE: Plaque characteristics and morphology are important indicators of plaque vulnerability. MRI-detected intraplaque hemorrhage has a great effect on plaque vulnerability. Expansive remodeling, which has been considered compensatory enlargement of the arterial wall in the progression of atherosclerosis, is one of the criteria of vulnerable plaque in the coronary circulation. The purpose of this study was risk stratification of carotid artery plaque through the evaluation of quantitative expansive remodeling and MRI plaque signal intensity. METHODS: Both preoperative carotid artery T1-weighted axial and long-axis MR images of 70 patients who underwent carotid endarterectomy (CEA) or carotid artery stenting (CAS) were studied. The expansive remodeling ratio (ERR) was calculated from the ratio of the linear diameter of the artery at the thickest segment of the plaque to the diameter of the artery on the long-axis image. Relative plaque signal intensity (rSI) was also calculated from the axial image, and the patients were grouped as follows: Group A = rSI ≥ 1.40 and ERR ≥ 1.66; Group B = rSI< 1.40 and ERR ≥ 1.66; Group C = rSI ≥ 1.40 and ERR < 1.66; and Group D = rSI < 1.40 and ERR < 1.66. Ischemic events within 6 months were retrospectively evaluated in each group. RESULTS: Of the 70 patients, 17 (74%) in Group A, 6 (43%) in Group B, 7 (44%) in Group C, and 6 (35%) in Group D had ischemic events. Ischemic events were significantly more common in Group A than in Group D (p = 0.01). CONCLUSIONS: In the present series of patients with carotid artery stenosis scheduled for CEA or CAS, patients with plaque with a high degree of expansion of the vessel and T1 high signal intensity were at higher risk of ischemic events. The combined assessment of plaque characterization with MRI and morphological evaluation using ERR might be useful in risk stratification for carotid lesions, which should be validated by a prospective, randomized study of asymptomatic patients.

Reduced cerebrovascular reserve is associated with an increased risk of postoperative ischemic lesions during carotid artery stenting.

BACKGROUND: Reduced cerebrovascular reserve (CVR) is associated with increased risk of ischemic events in carotid steno-occlusive diseases. OBJECTIVE: To determine whether pretreatment CVR can predict postoperative ischemic lesions after carotid artery stenting (CAS) by retrospective analysis. METHODS: We retrospectively reviewed the medical records of 46 patients (42 men; mean age 74.2±8.3 years) who underwent CAS and preprocedural cerebral blood flow measurement by quantitative single-photon emission CT. Ischemic lesions were evaluated by diffusion-weighted image (DWI) within 72 h after the intervention. We also evaluated plaque characteristics using black-blood MR plaque imaging. RESULTS: New ipsilateral DWI-positive lesions were found in 11 cases (23.9%). Patients were classified into two groups based on the presence or absence of new DWI-positive lesions, and no significant differences in characteristics were found between the DWI-positive and DWI-negative groups, except for age and CVR of the ipsilateral middle cerebral artery (MCA) territory. The DWI-positive group was significantly older than the DWI-negative group (79.7±4.1 vs 72.5±8.6 years; p=0.0085) and had lower average regional CVR (1.4±18.2% vs 22.4±25.8%; p=0.016). MR plaque imaging showed no significant difference in relative overall plaque MR signal intensity between the two groups (1.53±0.37 vs 1.34±0.26; p=0.113). In multivariate logistic regression analysis, lower CVR of the ipsilateral MCA territory (<11%) was the only independent risk factor for new ischemic lesions following CAS (OR=6.99; 95% CI 1.17 to 41.80; p=0.033). CONCLUSIONS: Impaired pretreatment CVR was associated with increased incidence of new infarction after CAS.

From patient to model: stereolithographic modeling of the cerebral vasculature based on rotational angiography.

We developed a method to produce tubular in vitro models of the cerebral vessels from real patient data. Three-dimensional data sets obtained from patients undergoing rotational angiography were used for stereolithographic biomodeling by using rapid prototyping technology. In a second step, tubular reproductions of the cerebral vessels were obtained by using the lost-wax technique. These reproductions can be useful for hemodynamic research and for the development and preclinical evaluation of new endovascular treatment methods.

Endovascular Therapy for Ruptured Cerebral Aneurysms in the Elderly: Poor Accessibility of the Guiding Catheter and Use of Local Anesthesia as the Predictors of Procedure-Related Rupture.

BACKGROUND: Endovascular therapy is favored for ruptured intracranial aneurysms in the elderly. However, poor accessibility to the aneurysm through the parent artery and use of local anesthesia in this age group may predispose to intraprocedural complications. OBJECTIVE: To evaluate whether age-related poor access to the ruptured target aneurysm and use of local anesthesia are associated with increased incidence of procedure-related rupture during endovascular embolization. METHODS: A total of 117 patients with 117 ruptured aneurysms underwent endovascular embolization at a single institution. Correlation of increasing age with poor accessibility of the guiding catheter was analyzed. In addition, the distance from the aneurysm to the guiding catheter was investigated to identify an association with incidence of procedure-related rupture. Correlation of local anesthesia with procedure-related rupture was also evaluated in the multivariable analysis. RESULTS: Increasing age was significantly associated with poor accessibility of the guiding catheter (P = .001, Mann-Whitney U test). Procedure-related rupture occurred in 9 of 117 aneurysms (7.7%). Longer distance between distal aneurysms and low-positioned guiding catheters carried a higher risk of procedure-related rupture than a shorter distance between proximal aneurysms and high-positioned guiding catheters (odds ratio, 19.3; 95% confidence interval, 1.84-201; P = .01, multivariable analysis). Use of local anesthesia was also a significant risk factor of procedure-related rupture by multivariable analysis. CONCLUSION: Increasing age was correlated with poor accessibility of the guiding catheter in endovascular embolization of ruptured intracranial aneurysms. Distally located aneurysms treated through a low-positioned guiding catheter and use of local anesthesia increased the risk of procedure-related rupture.