Clinical Impact of a Local Triage System Using the Emergent Large Vessel Occlusion Screen with a Rotation System of Thrombectomy-Capable Hospitals.

Objective: Early intervention with mechanical thrombectomy (MT) is expected to improve the functional outcome in patients with large vessel occlusion (LVO); however, a method for the effective detection of these patients in a prehospital setting and early transport to MT-capable hospitals has not been established. This study aimed to analyze the clinical impact and diagnostic performance of the emergent large vessel occlusion (ELVO) screen and its influence on the transportation time. Methods: The emergency medical services (EMS) in one of the secondary medical areas in Akita, Japan, introduced a prehospital triage system employing an ELVO screen and a rotation system of three MT-capable hospitals on December 1, 2021. Patients who were transferred to each of the three hospitals involved in the rotation system according to a predefined priority list from December 2021 to November 2022 were included in the triage group. Patients who underwent MT in the three hospitals before the introduction of the triage system were assigned to the pre-triage group. We compared the transportation time parameters between the two groups and analyzed the performance of the ELVO screen for the diagnosis of LVOs. This study was approved by the institutional review boards of all three hospitals. Results: Time parameters were compared between the 37 and 42 patients who underwent MT and had detailed data in the triage (n = 351) and pre-triage (n = 43) groups, respectively. The time from door to puncture tended to decrease in the triage group in all hospitals, with one hospital showing a statistically significant shortening of 14 min (p = 0.018). In the triage group, 209 ELVO screen-positive patients were present, with 60 (28.7%) of these having LVO. The sensitivity, specificity, positive and negative predictive values, and area under the curve of the ELVO screen to detect LVO under the present triage system were 87.0%, 47.2%, 28.7%, 93.7%, and 0.671, respectively. Conclusion: The present study demonstrated that the introduction of a triage system may have shortened the time required for MT. ELVO screen may be considered a useful marker for screening LVO in prehospital settings in terms of the sensitivity and negative predictive value; however, further improvement may be necessary to reduce the rate of false positive results.

Diffusion MRI Fiber Tractography and Benzodiazepine SPECT Imaging for Assessing Neural Damage to the Language Centers in an Elderly Patient after Successful Reperfusion Therapy.

BACKGROUND: Intravenous thrombolysis and mechanical thrombectomy are the first-line reperfusion therapies for acute ischemic stroke. Here, we describe the utility of diffusion magnetic resonance imaging (MRI) fiber tractography and 123I-iomazenil benzodiazepine receptor single-photon emission computed tomography to estimate the prognosis of post-stroke aphasia after successful reperfusion therapy. CASE REPORT: An 81-year-old man was admitted to the hospital approximately 3.5 h after the onset of symptoms, including decreased consciousness, right hemiparesis, and aphasia. An MRI revealed acute cerebral infarction due to M1 segment occlusion. Intravenous alteplase thrombolysis followed by endovascular thrombectomy resulted in recanalization of the left middle cerebral artery territory. A subsequent MRI showed no new ischemic or hemorrhagic lesions. Although the patient's motor hemiparesis gradually recovered, motor aphasia persisted. Diffusion MRI fiber tractography performed 2 weeks after admission revealed partial injury to the left arcuate fasciculus, indicated by lower fractional anisotropy values than on the contralateral side. A decreased benzodiazepine receptor density was also detected in the left perisylvian and temporoparietal cortices. The patient showed no clear signs of further improvement in the chronic stage post-stroke and was discharged to a nursing home after 3 months. CONCLUSIONS: The application of functional neuroimaging techniques to assess neuronal damage to the primary brain regions 2 weeks after reperfusion therapy for large-vessel occlusion may allow for an accurate prognosis of post-stroke aphasia. This may have a direct clinical implication for navigating subacute-to-chronic phases of rehabilitative care.

Factors Influencing Discontinuation of Clazosentan Therapy in Elderly Patients with Aneurysmal Subarachnoid Hemorrhage: A Retrospective Study from a Japanese Single Center.

BACKGROUND Clazosentan is an endothelin receptor antagonist approved in Japan for preventing cerebral vasospasm and vasospasm-associated cerebral ischemia and infarction. This study included elderly patients aged ≥75 years with aneurysmal subarachnoid hemorrhage (SAH) and aimed to evaluate the factors associated with discontinuing anti-vasospasm therapy with clazosentan. MATERIAL AND METHODS In this single-center retrospective observational study, we extracted diagnostic and therapeutic work-up data of consecutive 40 patients with SAH treated with clazosentan infusion (10 mg/h) as first-line anti-vasospasm therapy between May 2022 and August 2023. Patient data were compared between the discontinued and completed groups, and related factors for the discontinuation were further analyzed. RESULTS Clazosentan was discontinued in 22% (n=9) of patients due to intolerable dyspnea accompanied by hypoxemia at 5±3 days after therapy initiation, in which 44% (n=4) were elderly (≥75 years). Patients who discontinued clazosentan therapy showed significantly lower urine volumes compared with those who completed the therapy (P<0.05). Multivariate regression analysis revealed that day-to-day urine volume variance and older age were independent risk factors for drug cessation (P<0.05). The cut-off value for predicting clazosentan discontinuation was -0.7 mL/kg/h with sensitivity of 86% and specificity of 75% (area under the curve: 0.76±0.10; 95% confidence interval: 0.56-0.96; P=0.035). CONCLUSIONS Our results suggest that approximately 20% of SAH patients suffered from intolerable respiratory symptoms attributable to hypoxemia. We found that both reduced day-to-day urine volume variation and older age are independent risk factors for drug discontinuation.

Cardiopulmonary Events of the Elderly (≥75 Years) during Clazosentan Therapy after Subarachnoid Hemorrhage: A Retrospective Study from a Tertiary Stroke Center in Japan.

Clazosentan has been shown to prevent vasospasm and reduce mortality in patients after aneurysmal subarachnoid hemorrhage (SAH) and has been approved for clinical use in Japan; however, its systemic events in the elderly (aged ≥ 75 years) have not been well-documented. Here, we report serious/intolerable cardiopulmonary complications requiring discontinuation of drug therapy in elderly SAH patients. In this single-center case series study, medical records of consecutive SAH patients treated postoperatively with clazosentan (10 mg/h) between June 2022 and May 2023 were reviewed retrospectively. Thirty-three patients received clazosentan therapy, of whom six were elderly with a mean age of 80.3 ± 5.2 (range 75-89) years. Among them, despite no obvious medical history of systemic abnormalities, clazosentan was discontinued in three (50%) patients due to pleural effusion and hypoxemia with or without hypotension at 5 ± 3 days after therapy initiation, which was higher than the incidence for younger patients (15%). The elderly patients had significantly lower urine output (1935 ± 265 vs. 1123 ± 371 mL/day, p = 0.03) and greater weight gain (2.1 ± 1.1 vs. 4.2 ± 1.9 kg from baseline, p = 0.04) than patients who completed the therapy. One 89-year-old female developed congestive heart failure and hydrostatic pulmonary edema associated with increased intravascular and lung volumes even after therapy was discontinued, while the remaining two cases recovered within 2 days after drug cessation. These results suggest that elderly patients are more vulnerable to fluid retention and have a higher risk of cardiopulmonary complications during clazosentan therapy than younger patients. Careful monitoring of urine volume and weight gain and caution regarding age- and therapy-related hemodynamic insufficiencies are required.

Role of magnetic resonance vessel wall imaging in detecting and managing ruptured aneurysms among multiple intracranial aneurysms.

BACKGROUND: Wall enhancement of intracranial saccular aneurysms in high-resolution magnetic resonance vessel wall imaging (MR-VWI) might indicate a ruptured aneurysm. Therefore, this study aimed to determine the diagnostic ability of wall enhancement to detect the ruptured aneurysms among multiple aneurysms. METHODS: Patients with subarachnoid hemorrhage (SAH) and multiple intracranial aneurysms who underwent MR-VWI before craniotomy and clipping were included in the study. Three-dimensional T1-weighted fast spin-echo sequences were obtained before and after gadolinium injection. Aneurysm rupture was estimated based on the subarachnoid clot distribution, aneurysmal contours, and MR-VWI findings. We selectively performed surgical clipping and confirmed the rupture site intraoperatively. RESULTS: Thirteen patients with SAH with 13 ruptured and 17 unruptured aneurysms were treated at out facility. The accuracy rate of rupture site diagnosis using MR-VWI was 69.2% (9/13 cases). Each unruptured aneurysm was equally or more strongly enhanced in the other four cases than the ruptured aneurysms. In three of the four unruptured aneurysms with positive MR-VWI findings, atherosclerosis of the aneurysmal wall was observed during simultaneous or elective clipping surgery. Further, clipping surgery was performed without intraoperative rupture in two cases with the help of MR-VWI findings. CONCLUSION: Correct diagnosis of the rupture site using MR-VWI alone was unreliable due to false positives caused by the wall enhancement of unruptured aneurysms with atherosclerosis. Therefore, ruptured aneurysms should be detected using more information in addition to MR-VWI images. MR-VWI may be advantageous to determine surgical strategies when managing patients with SAH and multiple aneurysms.

Risk of Rupture After Intracranial Aneurysm Growth.

Importance: Unruptured intracranial aneurysms not undergoing preventive endovascular or neurosurgical treatment are often monitored radiologically to detect aneurysm growth, which is associated with an increase in risk of rupture. However, the absolute risk of aneurysm rupture after detection of growth remains unclear. Objective: To determine the absolute risk of rupture of an aneurysm after detection of growth during follow-up and to develop a prediction model for rupture. Design, Setting, and Participants: Individual patient data were obtained from 15 international cohorts. Patients 18 years and older who had follow-up imaging for at least 1 untreated unruptured intracranial aneurysm with growth detected at follow-up imaging and with 1 day or longer of follow-up after growth were included. Fusiform or arteriovenous malformation-related aneurysms were excluded. Of the 5166 eligible patients who had follow-up imaging for intracranial aneurysms, 4827 were excluded because no aneurysm growth was detected, and 27 were excluded because they had less than 1 day follow-up after detection of growth. Exposures: All included aneurysms had growth, defined as 1 mm or greater increase in 1 direction at follow-up imaging. Main Outcomes and Measures: The primary outcome was aneurysm rupture. The absolute risk of rupture was measured with the Kaplan-Meier estimate at 3 time points (6 months, 1 year, and 2 years) after initial growth. Cox proportional hazards regression was used to identify predictors of rupture after growth detection. Results: A total of 312 patients were included (223 [71%] were women; mean [SD] age, 61 [12] years) with 329 aneurysms with growth. During 864 aneurysm-years of follow-up, 25 (7.6%) of these aneurysms ruptured. The absolute risk of rupture after growth was 2.9% (95% CI, 0.9-4.9) at 6 months, 4.3% (95% CI, 1.9-6.7) at 1 year, and 6.0% (95% CI, 2.9-9.1) at 2 years. In multivariable analyses, predictors of rupture were size (7 mm or larger hazard ratio, 3.1; 95% CI, 1.4-7.2), shape (irregular hazard ratio, 2.9; 95% CI, 1.3-6.5), and site (middle cerebral artery hazard ratio, 3.6; 95% CI, 0.8-16.3; anterior cerebral artery, posterior communicating artery, or posterior circulation hazard ratio, 2.8; 95% CI, 0.6-13.0). In the triple-S (size, site, shape) prediction model, the 1-year risk of rupture ranged from 2.1% to 10.6%. Conclusion and Relevance: Within 1 year after growth detection, rupture occurred in approximately 1 of 25 aneurysms. The triple-S risk prediction model can be used to estimate absolute risk of rupture for the initial period after detection of growth.

Dissection of the Superficial Temporal Artery: Significance and Performance with Bipolar Forceps.

BACKGROUND: Adequate bypass harvesting of the superficial temporal artery (STA) is a standard procedure for every neurosurgeon, so mastery of techniques for its management and care is mandatory. METHODS: Here, we report the effectiveness of using the bipolar forceps as a novel procedure. RESULTS: This procedure improves safety, efficiency, and bleeding compared to the usual dissection. CONCLUSIONS: In cases requiring an STA donor, this technique may be as useful as the traditional method and could become part of the neurosurgeon's armamentarium.

OCCUPATIONAL RADIATION EXPOSURE OF THE EYE IN NEUROVASCULAR INTERVENTIONAL PHYSICIAN.

Neurovascular interventional radiology (neuro-IR) procedures tend to require an extended fluoroscopic exposure time and repeated digital subtraction angiography. To evaluate the actual measurement of eye lens dose using a direct eye dosemeter in neuro-IR physicians is important. Direct dosimetry using the DOSIRIS™ (IRSN, France) [3 mm dose equivalent, Hp(3)] was performed on 86 cases. Additionally, a neck personal dosemeter (glass badge) [0.07 mm dose equivalent, Hp(0.07)] was worn outside the protective apron to the left of the neck. The average doses per case of neuro-IR physicians were 0.04 mSv/case and 0.02 mSv/case, outside and inside the radiation protection glasses, respectively. The protective effect of radiation protection glasses was approximately 60%. The physician eye lens dose tended to be overestimated by the neck glass badge measurements. A correct evaluation of the lens dose [Hp(3)] using an eye dosemeter such as DOSIRIS™ is needed for neuro-IR physicians.

Secular Trends in the Background of Intracerebral Hemorrhage from 2010 to 2015.

OBJECTIVE: Direct oral anticoagulants (DOACs) were recently introduced for the clinical use in stroke prevention, and they are reported to show a lower risk of intracerebral hemorrhage (ICH) compared to warfarin. We were interested to know whether there is any change in clinical backgrounds of ICH patients to date. METHODS: From 2010 to 2015, ICH patients admitted to our hospital were consecutively screened (n = 658). Hematoma size was assessed by brain computed tomography images on admission. Outcome was measured by the modified Rankin Scale, and favorable outcome was defined as modified Rankin Scale 0-2. Biennial trends were compared in 3 periods, P1: 2010-2011, P2: 2012-2013, and P3: 2014-2015. RESULTS: The percentage of ICH patients taking antithrombotics had been slightly decreasing (P = .245: [P1] 33.0%, [P2] 27.4%, and [P3] 26.2%). The frequency of patients taking antiplatelets had significantly decreased (P = .001: [P1] 50.7%, [P2] 44.3%, and [P3] 22.8%), and those taking DOACs had significantly increased (P = .001: [P1] 1.4%, [P2] 4.9%, and [P3] 19.3%). Frequency of favorable outcomes in patients taking antithrombotics was slightly increased in P3 compared to P1 and P2 (23.3%, 21.1%, and 21.3%, respectively). There was no significant difference in hematoma size between patients taking warfarin and DOACs. CONCLUSIONS: Number of ICH patients taking antithrombotics has been slightly decreasing and the percentage taking DOACs among ICH has been increasing for 6 years.

Impact of Right-Sided Aneurysm, Rupture Status, and Size of Aneurysm on Perforator Infarction Following Microsurgical Clipping of Posterior Communicating Artery Aneurysms with a Distal Transsylvian Approach.

BACKGROUND: Posterior communicating artery (PCoA) aneurysms are among the most common aneurysms. Because blockage of the PCoA and perforators can cause adverse outcomes, occlusion of these arteries by surgical clipping should be avoided. The impact of factors on PCoA perforator infarction when using a distal transsylvian approach for PCoA aneurysms was examined. METHODS: A total of 183 patients underwent PCoA aneurysm clipping, excluding application of fenestrated clips. Patients were divided into 2 groups: patients with PCoA perforator infarction (infarction group) and patients without infarction (noninfarction group). Multiple factors were analyzed in the 2 groups. RESULTS: Twenty-two of the 183 patients (12.0%) showed perforator infarction, mainly on magnetic resonance imaging evaluation, resulting in permanent deficits in 2 patients (1.1%). The proportion of right-sided operations (86.4% vs. 53.4%; P = 0.005) and surgery for rupture (90.9% vs. 55.9%; P = 0.002) were significantly higher in the infarction group than in the noninfarction group. Aneurysms were significantly larger in the infarction group (8.4 ± 3.8 mm) than in the noninfarction group (6.3 ± 3.0 mm; P = 0.02). Ruptured status (odds ratio [OR], 7.35; P = 0.01), right side (OR, 5.19; P = 0.01), and aneurysm size (OR, 1.18; P = 0.02) remained independent predictors of perforator infarction on multivariate logistic regression analysis. CONCLUSIONS: Ruptured status, right side, and large PCoA aneurysm were independent predictors of PCoA perforator infarction. Symptoms due to PCoA perforating infarction were mostly transient and rarely affected outcomes.

Anti-inflammatory and antiplatelet effects of non-vitamin K antagonist oral anticoagulants in acute phase of ischemic stroke patients.

BACKGROUND: Recently, non-vitamin K antagonist oral anticoagulants such as direct thrombin and direct factor Xa inhibitors have been prescribed for prevention of embolic stroke. While in Japan, argatroban, also a direct thrombin inhibitor, is available for the treatment of atherothrombotic stroke patients. This study aimed to explore whether there is any differences between direct thrombin and direct factor Xa inhibitors regarding the inhibiting effect against thrombogenesis in the clinical setting of acute ischemic stroke. METHODS: Acute ischemic stroke patients newly prescribed anti-thrombotic agents were consecutively screened, and 44 patients with single medicine were enrolled (median 72.0 years-old). Blood samples were obtained at 1 and 2 weeks after the medication started. The extent of anticoagulation activity, inflammatory markers and platelet aggregation were assessed. Patients with antiplatelets were used as control. RESULTS: Prescribed antithrombotics were dabigatran (group D: n = 12), apixaban (group A: n = 14) and antiplatelet agents (group P: n = 18). Prevalence of stroke risks and anticoagulation activity were not different between groups D and A. The alteration of inflammatory markers in a week in the group A showed similar trend to those in the group P. The group D presented relatively lower amount of high-sensitive C-reactive protein and higher amount of pentraxin-3 compared with groups A and P. While 88.9% of group P patients showed decreased platelet aggregation activity with adenosine diphosphate, 55.6% of group D and 40.0% of group A presented the inhibition of platelet aggregation activity. CONCLUSIONS: Even in acute ischemic stroke patients, both apixaban and dabigatran equally showed the anticoagulation activity. The reduction of inflammatory response might be prominent in apixaban, whereas the inhibition of platelet aggregation activity might be evident in dabigatran.

Bedside assessment of regional cerebral perfusion using near-infrared spectroscopy and indocyanine green in patients with atherosclerotic occlusive disease.

This pilot study aimed to investigate the utility of near-infrared spectroscopy/indocyanine green (NIRS/ICG) for examining patients with occlusive cerebrovascular disease. Twenty-nine patients with chronic-stage atherosclerotic occlusive cerebrovascular disease were included. The patients were monitored using NIRS at the bedside. Using ICG time-intensity curves, the affected-to-unaffected side ratios were calculated for several parameters, including the maximum ICG concentration (ΔICGmax), time to peak (TTP), rise time (RT), and blood flow index (BFI = ΔICGmax/RT), and were compared to the affected-to-unaffected side ratios of the regional cerebral blood flow (rCBF) and regional oxygen extraction fraction (rOEF) obtained using positron emission tomography with 15O-labeled gas. The BFI ratio showed the best correlation with the rCBF ratio among these parameters (r = 0.618; P = 0.0004), and the RT ratio showed the best correlation with the rOEF ratio (r = 0.593; P = 0.0007). The patients were further divided into reduced rCBF or elevated rOEF groups, and the analysis revealed significant related differences. The present results advance the measurement of ICG kinetics using NIRS as a useful tool for the detection of severely impaired perfusion with reduced rCBF or elevated rOEF. This method may be applicable as a monitoring tool for patients with acute ischemic stroke.

Outcome of Secondary Stroke Prevention in Patients Taking Non-Vitamin K Antagonist Oral Anticoagulants.

BACKGROUND: Since non-vitamin K antagonist oral anticoagulants (NOACs) were released for clinical use, many studies have investigated its effectiveness in stroke prevention. In this study, to determine whether or not there is a difference in outcome in secondary stroke prevention between warfarin and NOACs, patients with embolic stroke with newly prescribed anticoagulants were prospectively analyzed. METHODS: Patients with acute ischemic stroke, who newly started anticoagulant therapy, were consecutively asked to participate in this study. Enrolled patients (76.3 ± 11.0 years old) were classified into warfarin (n = 48), dabigatran (n = 73), rivaroxaban (n = 49), and apixaban (n = 65). The outcome in 1 year was prospectively investigated at outpatient clinic or telephone interview. Recurrence of stroke and death was considered as the critical incidence. RESULTS: The prevalence of risk factors was not different among all medicines. Patients with dabigatran showed significantly younger onset age (P < .001: 72.2 years old) and milder neurologic deficits than patients on other medicines (P < .001). Cumulative incident rates were 7.1%, 15.3%, 19.0%, and 29.7% for dabigatran, apixaban, rivaroxaban, and warfarin, respectively. Dabigatran showed relatively better outcome compared with warfarin (P = .069) and rivaroxaban (P = .055). All patients on NOACs presented lower cumulative stroke recurrence compared with warfarin. CONCLUSION: Even in the situation of secondary stroke prevention, noninferiority of NOACs to warfarin might be demonstrated.

Treatment of Recurrent Intracranial Aneurysms After Neck Clipping: Novel Classification Scheme and Management Strategies.

BACKGROUND: Recurrent aneurysms after initial clipping have been discussed as an important issue in the surgical management of aneurysm. OBJECTIVE: To report our experience with recurrent cerebral aneurysms after neck clipping and to discuss classification and recommended management. METHODS: Aneurysm treatments from a single institution over a 20-year period were retrospectively reviewed. Twenty-three recurrent aneurysms in 23 patients were managed during the study period. Recurrent aneurysms were classified using the concepts of closure line and closure plane, as follows. Type 1: neck situated in an almost different site from the previous clip. Type 2: existing closure plane and reconstructive closure plane are almost the same. Type 3: existing closure plane and reconstructive closure plane cross (type 3a); in rare cases, the existing closure line is sufficiently distant from the neck (type 3b). Type 4: no reconstructive closure line is identifiable. RESULTS: Nine patients presented with subarachnoid hemorrhage at recurrence. The mean interval to recurrence was 15.0 years. Management comprised clipping with elective subsequent old-clip removal (n = 7), clipping with preceding old-clip removal (n = 2), bypass occlusion (n = 1), coating (n = 1), combined surgery (n = 1), endovascular surgery (n = 4), and observation (n = 3). Therapeutic intervention was not indicated in 4 patients. Types 3a and 4 required more complex surgical procedures or coil embolization. Procedural complications were observed in 2 patients. CONCLUSION: A small but definite propensity toward recurrence after neck clipping exists, and most recurrent aneurysms require some form of retreatment. The novel classification scheme may provide conceptual clarity and therapeutic guidance for decision making.

Safe time duration for temporary middle cerebral artery occlusion in aneurysm surgery based on motor-evoked potential monitoring.

BACKGROUND: Temporary vessel occlusion of the parent artery is an essential technique for aneurysm surgery. Our aim was to clarify the safe time for temporary occlusion for aneurysm surgery, that is the "safe time duration" (STD), in which brain tissue exposed to ischemia will almost never fall into even the ischemic penumbra during temporary occlusion of the middle cerebral artery (MCA), and even transient postoperative motor impairment will be rare using intraoperative motor-evoked potentials (MEP). METHODS: Twenty-four patients underwent MCA aneurysm clipping surgery with MEP monitoring for 13 ruptured aneurysms and 11 unruptured aneurysms. The duration of vessel occlusion in patients without MEP changes was measured as the STD. Average STD was calculated as 95% confidence interval for the population mean using sample data from patients with MEP changes and patients without changes. RESULTS: All 24 patients received proximal flow control only. Five patients (20.8%) developed significant intraoperative MEP changes. Time to MEP change (i.e., STD) in these patients was 4.6 ± 2.1 min. In patients without MEP changes, STD was 2.7 ± 1.4 min. Average STD was thus 3.1 ± 0.7 min. CONCLUSIONS: The 95% lower confidence limit for average STD was 2.4 min when applying temporary occlusion on the proximal side of the MCA. This STD resembled that previously reported for temporary proximal occlusion of the internal carotid artery.

ELAPSS score for prediction of risk of growth of unruptured intracranial aneurysms.

OBJECTIVE: To develop a risk score that estimates 3-year and 5-year absolute risks for aneurysm growth. METHODS: From 10 cohorts of patients with unruptured intracranial aneurysms and follow-up imaging, we pooled individual data on sex, population, age, hypertension, history of subarachnoid hemorrhage, and aneurysm location, size, aspect ratio, and shape but not on smoking during follow-up and family history of intracranial aneurysms in 1,507 patients with 1,909 unruptured intracranial aneurysms and used aneurysm growth as outcome. With aneurysm-based multivariable Cox regression analysis, we determined predictors for aneurysm growth, which were presented as a risk score to calculate 3-year and 5-year risks for aneurysm growth by risk factor status. RESULTS: Aneurysm growth occurred in 257 patients (17%) and 267 aneurysms (14%) during 5,782 patient-years of follow-up. Predictors for aneurysm growth were earlier subarachnoid hemorrhage, location of the aneurysm, age >60 years, population, size of the aneurysm, and shape of the aneurysm (ELAPSS). The 3-year growth risk ranged from <5% to >42% and the 5-year growth risk from <9% to >60%, depending on the risk factor status. CONCLUSIONS: The ELAPSS score consists of 6 easily retrievable predictors and can help physicians in decision making on the need for and timing of follow-up imaging in patients with unruptured intracranial aneurysms.

Timing of retreatment for patients with previously coiled or clipped intracranial aneurysms: Analysis of 156 patients with multiple treatments.

BACKGROUND: Some patients require a second surgical intervention for recurrence of treated aneurysms, untreated aneurysms in patients with multiple lesions, or de novo aneurysm. This retrospective review of the data was undertaken to evaluate when retreatment is necessary after initial aneurysm treatment. METHODS: Cerebral aneurysms in 1755 patients were treated via clipping or coiling between January 1995 and September 2012. Postoperative follow-up was performed at 6 months after treatment and was repeated every 12 months (or longer) after treatment using three-dimensional computed tomography angiography or magnetic resonance angiography. RESULTS: A cumulative total of 156 patients (8.9%) (117 women, 39 men; mean age: 55.0 years; range: 25-79 years) needed retreatment for rupture or regrowth of aneurysm (n = 31; ruptured (R)/remaining unruptured (U), 26/5), formation of de novo aneurysm (n = 45; R/U, 23/22), known untreated aneurysm in patients with multiple lesions (n = 78; R/U, 5/73), and hemorrhage from undetected aneurysm (n = 2). The regrowth risk is higher after endovascular treatment than after craniotomy and clipping. Median time to retreatment was 187 months (range: 11-280 months) for regrowth, 165 months (range: 22-330 months) for de novo, and 24 months (range: 2.8-417 months) for known untreated aneurysm. Regrowth or known with subarachnoid hemorrhage were frequently treated within 2 years from initial treatment. CONCLUSIONS: Aneurysms with residua or untreated aneurysms in patients with multiple lesions carry a risk of bleeding during a relatively short period, whereas there is a small but significant risk of de novo formation and subsequent hemorrhage at over 10 years after previous treatment.

Recanalization of a ruptured vertebral artery dissecting aneurysm after occlusion of the dilated segment only.

BACKGROUND: Internal trapping in which the dissecting aneurysm is occluded represents reliable treatment to prevent rebleeding of ruptured vertebral artery (VA) dissecting aneurysms. Various methods of internal trapping are available, but which is most appropriate for preventing both recanalization of the VA and procedural complications is unclear. CASE DESCRIPTION: A 61-year-old male presented with subarachnoid hemorrhage caused by rupture of a left VA dissecting aneurysm. Only the dilated segment of the aneurysm was occluded by coil embolization. Sixteen days after embolization, angiography showed recanalization of the treated left VA with blood supplying the dilated segment of the aneurysm, which showed morphological change between just proximal to the coil mesh and just distal to a coil, and antegrade blood flow through this part. Pathological examination showed that the rupture site that had appeared to be the most dilated area on angiography was located just above the orifice of the entrance. However, we think that this case of ruptured aneurysm had an entrance into a pseudolumen that existed proximal to the dilated segment, with antegrade recanalization occurring through the pseudolumen with morphological change because of insufficient coil obliteration of the entrance in the first therapy. CONCLUSIONS: This case suggests that occlusion of both the proximal and dilated segments of a VA dissecting aneurysm will prevent recanalization, by ensuring that any entrance to a pseudolumen of the aneurysm is completely closed. Careful follow-up after internal trapping is important, since antegrade recanalization via a pseudolumen may occur in the acute stage.

Quantitative cerebral perfusion assessment using microscope-integrated analysis of intraoperative indocyanine green fluorescence angiography versus positron emission tomography in superficial temporal artery to middle cerebral artery anastomosis.

BACKGROUND: Intraoperative qualitative indocyanine green (ICG) angiography has been used in cerebrovascular surgery. Hyperperfusion may lead to neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. The purpose of this study is to quantitatively evaluate intraoperative cerebral perfusion using microscope-integrated dynamic ICG fluorescence analysis, and to assess whether this value predicts hyperperfusion syndrome (HPS) after STA-MCA anastomosis. METHODS: Ten patients undergoing STA-MCA anastomosis due to unilateral major cerebral artery occlusive disease were included. Ten patients with normal cerebral perfusion served as controls. The ICG transit curve from six regions of interest (ROIs) on the cortex, corresponding to ROIs on positron emission tomography (PET) study, was recorded. Maximum intensity (IMAX), cerebral blood flow index (CBFi), rise time (RT), and time to peak (TTP) were evaluated. RESULTS: RT/TTP, but not IMAX or CBFi, could differentiate between control and study subjects. RT/TTP correlated (|r| = 0.534-0.807; P < 0.01) with mean transit time (MTT)/MTT ratio in the ipsilateral to contralateral hemisphere by PET study. Bland-Altman analysis showed a wide limit of agreement between RT and MTT and between TTP and MTT. The ratio of RT before and after bypass procedures was significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.60 ± 0.032 and 0.80 ± 0.056, respectively; P = 0.017). The ratio of TTP was also significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.64 ± 0.081 and 0.85 ± 0.095, respectively; P = 0.017). CONCLUSIONS: Time-dependent intraoperative parameters from the ICG transit curve provide quantitative information regarding cerebral circulation time with quality and utility comparable to information obtained by PET. These parameters may help predict the occurrence of postoperative HPS.

[Contribution of increasing age to carotid plaque morphology and symptoms].

OBJECTIVE: Aging is considered to cause atherosclerotic changes in the carotid artery, but few studies have evaluated this relationship. In this study, we used carotid plaques removed from patients with carotid artery stenosis and investigated how aging contributes to carotid plaque morphology and symptoms. MATERIALS AND METHODS: A total of 60 patients(55 men, 5 women; mean age, 70.5 years; range, 53-85 years) treated at our hospital between January 2009 and April 2012 were enrolled in this study. All patients underwent carotid endarterectomy; their carotid plaques were stained with hematoxylin-eosin and/or Elastica-Masson stain and examined by a pathologist. Using these data, the carotid systolic velocity and plaque morphology were analyzed considering the age by decade as well as the symptomatology. RESULTS: Of the 60 patients, 29 were symptomatic(transient ischemic attack (TIA) in 8 patients; infarction in 20;and amaurosis in 1). Symptoms were less common as patient age increased. The incidence of TIA also tended to decrease with an increase in age, although the opposite trend was seen with infarction. In plaque morphology, the presence of active plaque, macrophage, inflammatory infiltration, and capillary angiogenesis decreased as age increased, while the presence of degenerative plaques, decrease in smooth muscle cell number, and calcification inversely increased. Active, degenerative, and combined (active/degenerative) lesions are statistically unrelated to symptoms as well as systolic velocity (cm/sec) at the carotid stenosis. The rates of hemorrhagic lesions were similar among decades, but the lesion statistically contributed to increasing symptoms (p=0.0045) and increasing systolic velocity (p=0.031). CONCLUSION: Increasing age contributes to morphological changes in carotid plaques and symptoms. When hemorrhagic lesions are suspected in carotid plaques, patients will be symptomatic and may require surgery.