Treatment of wide-necked aneurysms with the Low-profile Visualized Intraluminal Support (LVIS Jr) device: a multicenter experience.

BACKGROUND: The Low-profile Visualized Intraluminal Support (LVIS) Junior stent is newly approved for the treatment of wide-necked intracranial aneurysms. OBJECTIVE: To report our multicenter experience with use of the LVIS Jr device. METHODS: The neurointerventional databases of the participating institutions were retrospectively reviewed for aneurysms treated with LVIS Jr from the time of Food and Drug Administration approval until February 2016. All patients in the study period were included. Clinical presentation, aneurysm location, aneurysm size, vessel size, procedural complications, clinical and imaging follow-up were included in the analysis. RESULTS: Eighty-five patients (54 female and 31 male) met the inclusion criteria for the study. Sixty-eight (80%) of the aneurysms were unruptured and the remainder were ruptured. The most common location of the treated aneurysms was anterior communicating artery (36%), middle cerebral artery bifurcation (22%), and basilar terminus (15%). The mean aneurysm size was 6.1 mm. The mean minimum parent vessel size was 2.3 mm. The LVIS Jr was successfully deployed in all but one case (99%). Initial angiographic results demonstrated Roy-Raymond class 1-2 occlusions in 61/84 patients (73%). At 6 months, 85% of the patients seen at follow-up had Roy-Raymond class 1-2 aneurysm occlusion. No procedure-related deaths occurred. Two cases of procedure-related complications (intraprocedural rupture and delayed rupture at day 2) were seen, leading to permanent neurologic morbidity. Both these cases were in patients with ruptured aneurysms. CONCLUSIONS: The LVIS Jr is a technically feasible, safe, and effective treatment for wide-necked intracranial aneurysms. Early results are promising but will need to be corroborated with longer-term follow-up.

Pipeline endovascular device for the treatment of intracranial aneurysms at the level of the circle of Willis and beyond: multicenter experience.

BACKGROUND AND PURPOSE: The aim of our study was to evaluate the safety and efficacy of the pipeline endovascular device for the treatment of anterior circulation aneurysms at the level of the circle of Willis and beyond. METHODS: A consecutive series of 25 patients (24 unruptured and one ruptured) with anterior circulation aneurysms treated with a pipeline endovascular device were included in the analysis. RESULTS: We found two minor clinical events (resolved within 7 days of the procedure), one major event (symptoms present after 7 days), and no mortality. There were no aneurysm ruptures or parenchymal hemorrhages during follow-up. The modified Rankin Scale (mRS) scores at 3 and 6 months did not change from the prior mRS score for all cases except 1. There was one asymptomatic periprocedural event. There were three intraprocedural complications which resolved without clinical consequences. Six month follow-up angiograms were obtained for 22 aneurysms, showing complete occlusion in 14 (64%) and significantly decreased residual filling in 8 (36%). The status of branches originating from the aneurysm sacs was evaluated in 14 angiograms: 11 were patent (79%), 2 had moderate reduction (14%) and 1 (7%) was occluded. We found six cases of in-stent stenosis (27%) on 6 month DSA, with only one symptomatic case. CONCLUSIONS: The pipeline embolization device provides a feasible and technically safe solution for aneurysms at and beyond the circle of Willis. Preliminary results are promising but larger series with longer term follow-up examinations are required to show the long term safety and durability of this treatment alternative.

Unilateral rete mirabile as a result of segmental agenesis of the ascending petrous segment of the internal carotid artery: embryology, differential diagnosis and clinical implications.

We describe an extremely rare case of unilateral rete mirabile in a young woman and discuss its significance in embryological development as well as its radiological aspects, differential diagnosis and potential clinical implications.

Closed-cell stent for coil embolization of intracranial aneurysms: clinical and angiographic results.

BACKGROUND AND PURPOSE: Recanalization is observed in 20-40% of endovascularly treated intracranial aneurysms. To further reduce the recanalization and expand endovascular treatment, we evaluated the safety and efficacy of closed-cell SACE. MATERIALS AND METHODS: Between 2007 and 2010, 147 consecutive patients (110 women; mean age, 54 years) presenting at 2 centers with 161 wide-neck ruptured and unruptured aneurysms were treated by using SACE. Inclusion criteria were wide-neck aneurysms (>4 mm or a dome/neck ratio ≤ 2). Clinical outcomes were assessed by the mRS score at baseline, discharge, and follow-up. Aneurysm occlusion was assessed on angiograms by using the RS immediately after SACE and at follow-up. RESULTS: Eighteen aneurysms (11%) were treated following rupture. Procedure-related mortality and permanent neurologic deficits occurred in 2 (1.4%) and 5 patients (3.4%), respectively. In total, 7 patients (4.8%) died, including 2 with reruptures. Of the 140 surviving patients, 113 (80.7%) patients with 120 aneurysms were available for follow-up neurologic examination at a mean of 11.8 months. An increase in mRS score from admission to follow-up by 1, 2, or 3 points was seen in 7 (6.9%), 1 (1%), and 2 (2%) patients, respectively. Follow-up angiography was performed in 120 aneurysms at a mean of 11.9 months. Recanalization occurred in 12 aneurysms (10%), requiring retreatment in 7 (5.8%). Moderate in-stent stenosis was seen in 1 (0.8%), which remained asymptomatic. CONCLUSIONS: This series adds to the evidence demonstrating the safety and effectiveness of SACE in the treatment of intracranial aneurysms. However, SACE of ruptured aneurysms and premature termination of antiplatelet treatment are associated with increased morbidity and mortality.

Avoiding complications in neurosurgical interventional procedures.

The aim of this paper is to describe common complications during neurosurgical interventional procedures. We describe our experience and review the literature about how to avoid complications during diagnostic cerebral angiography and neurosurgical interventional procedures. Recent technological advances have expanded the therapeutic options of neuroendovascular interventions. However, with higher complexity there is also an increased risk of complications. Common complications include hematoma at the puncture site, arterial dissection and microembolism. Treatment of complex aneurysms and arteriovenous malformations involves a higher complication rate. Standardized training and operator's certification reduces the risk of complications. It is also important to work with specialized ancillary staff and to provide dedicated neurocritical care after the neuroendovascular intervention.

Performance and training standards for endovascular ischemic stroke treatment.

Stroke is the third leading cause of death in the USA, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750,000 new strokes that occur each year, resulting in 200,000 deaths, or 1 of every 16 deaths, per year in the USA alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in two randomized trials and numerous case series. Although two devices have been granted FDA approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies which historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. The participating member organizations of the Neurovascular Coalition involved in the writing and endorsement of this document are the Society of NeuroInterventional Surgery, the American Academy of Neurology, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Cerebrovascular Section, and the Society of Vascular & Interventional Neurology.

Cerecyte versus platinum coils in the treatment of intracranial aneurysms: packing attenuation and clinical and angiographic midterm results.

BACKGROUND AND PURPOSE: As modifications are made to coils, monitoring the safety profile, ability to achieve high packing attenuation, and durability of occlusion as compared to the standard bare platinum coils is of paramount importance. We compared packing attenuation, initial occlusion, and recanalization rates between Cerecyte and bare platinum coils in the treatment of ruptured and unruptured cerebral aneurysms. MATERIALS AND METHODS: We compared 63 patients (67 aneurysms) treated with Cerecyte coils with 65 patients (70 aneurysms) treated by using bare platinum coils. Results were classified by the Raymond score. Clinical outcomes were assessed by using a modified Rankin Scale. Angiographic and clinical follow-ups were performed routinely at 6 and 12 months after the intervention. RESULTS: In the Cerecyte group, complete occlusion of the aneurysm (grade 1) was accomplished in 49% (33/67), a small residual neck (grade 2) was seen in 21% (14/67), and dome filling (grade 3) was seen in 30% (20/67). In the platinum group, 41% (29/70) were grade 1, 39% (27/70) were grade 2, and 20% (14/70) were grade 3 immediately postembolization. Mean packing attenuation was 43 +/- 28% in the Cerecyte group and 40 +/- 23% in the bare platinum group (P = .68). Twelve-month follow-up data were available for 54% (36/67) of the Cerecyte population and 43% (30/70) of the bare platinum population. There were 5 cases of neck recanalization (11%) in the Cerecyte group and 11 cases (23%) in the bare platinum group (P = .17). No rebleeds were noted in the follow-up period. CONCLUSIONS: Cerecyte coils have a satisfactory safety profile. We were able to achieve high packing attenuations and initial occlusion rates similar to those obtainable with platinum coils.

Performance and training standards for endovascular ischemic stroke treatment.

Stroke is the third leading cause of death in the USA, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750,000 new strokes that occur each year, resulting in 200,000 deaths, or 1 of every 16 deaths, per year in the USA alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in two randomized trials and numerous case series. Although two devices have been granted FDA approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies which historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. The participating member organizations of the Neurovascular Coalition involved in the writing and endorsement of this document are the Society of NeuroInterventional Surgery, the American Academy of Neurology, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Cerebrovascular Section, and the Society of Vascular & Interventional Neurology.

Complex-shaped platinum coils for brain aneurysms: higher packing density, improved biomechanical stability, and midterm angiographic outcome.

BACKGROUND AND PURPOSE: Five to 60% of coiled brain aneurysms recanalize, generally because of coil compaction. In vitro exclusive use of complex-shaped coils allows better packing of the aneurysmal sac and the neck as compared with helical coils. We report a single-center, prospective study using complex coils. Safety, packing density, and recanalization rate were evaluated. MATERIALS AND METHODS: Seventy-seven aneurysms were embolized using complex coils alone. Aneurysms had a volume of 265 mm3 (diameter: 7.1+/-3.3 mm) and a neck size of 4.1+/-1.8 mm (range: 1.5-12 mm). Average follow-up available in 31 patients was 10.5+/-7.6 months (range: 3-36 months). Primary angiographic endpoints included aneurysmal recanalization and (re)rupture. Primary adverse events included stroke or death. RESULTS: Complete or near-complete occlusion was achieved in all of the aneurysms but required balloon assistance in 24.6%. The packing density was computed as 37%+/-13%. No rerupture was observed during the follow-up interval. Recanalization was seen in 4 (12.9%) of 31. Two basilar tip aneurysms underwent a safe and complete recoiling. Periprocedural nondevice-related neurologic deficits were seen in 2 (2.9%) of 69 patients. CONCLUSIONS: The use of complex-shaped coils allows higher packing density, which may improve the recanalization rate. Basilar tip aneurysms remain a challenge.

Relationship between magnetic resonance arterial patency and perfusion-diffusion mismatch in acute ischemic stroke and its potential clinical use.

BACKGROUND: In patients with acute ischemic stroke the magnetic resonance (MR) perfusion-diffusion mismatch pattern (perfusion lesion at least 20% larger than the lesion on diffusion-weighted imaging) may indicate ischemically threatened but viable tissue. To our knowledge, the relationship of this MR pattern to serial changes in MR angiography (MRA) has not been reported. OBJECTIVES: To investigate the relationship between MRA changes and patterns of diffusion-weighted imaging and perfusion abnormalities and to determine if the information obtained could be used in clinical management. METHODS: The MR studies of 35 patients who had undergone sequential multimodality MR imaging studies within the first 4 days of stroke were reviewed. All lesions were in the internal carotid artery territory distribution. Magnetic resonance angiographies were read by 2 observers blinded to the clinical data. RESULTS: During the first 24 hours a perfusion-diffusion mismatch was present in 22 (92%) of the 24 patients with an MRA arterial occlusive lesion. (At this time 5 [46%] of the 11 patients with a normal MRA [P =.006] also had a mismatch.) Two to 4 days after stroke, of these 22 patients resolution of the mismatch occurred in 8 (87%) of 9 patients with recanalization on MRA compared with 5 (39%) of 13 patients without arterial recanalization (P =.03). Resolution of mismatch occurred in 3 (60%) of 5 patients with a normal MRA and a mismatch at the first time point. CONCLUSIONS: Concordance between MRA and the MR perfusion-diffusion mismatch pattern provides supportive evidence for an arterial vascular basis for this MR signature in acute stroke. Discordance between MRA lesions and mismatch may result from arterial branch occlusions undetected by MRA or from an alternate mechanism for the mismatch. The MR imaging patterns identified extend our understanding of the pathophysiology of stroke and may contribute to the improvement of stroke management in the future.

Diffusion-weighted imaging and National Institutes of Health Stroke Scale in the acute phase of posterior-circulation stroke.

BACKGROUND: Occlusive disease of the posterior circulation represents a heterogeneous group of strokes that differ in etiology, clinical presentation, and prognosis. Computed tomography provides suboptimal visualization of posterior-circulation infarcts. Anatomic definition of traditional magnetic resonance imaging sequences has been used for clinicoradiologic correlation in patients with posterior-circulation disease. These studies focused on the subacute rather than the acute phase of ischemia. Lesion volumes on diffusion-weighted imaging (DWI) and perfusion imaging were found to have a good correlation with 24-hour National Institutes of Health stroke scale (NIHSS) score in ischemia of the anterior circulation. Correlation between NIHSS score and lesion volume in posterior-circulation infarcts is unknown. OBJECTIVES: To investigate whether DWI is useful for clinicoradiologic correlation of posterior-circulation ischemia within 24 hours after symptom onset and whether NIHSS score correlates with lesion volumes in patients with posterior-circulation stroke. PATIENTS AND METHODS: In a database analysis of 631 patients with stroke from June 26, 1996, to July 30, 1999, 115 patients (18%) had symptoms of posterior-circulation ischemia by imaging and clinical criteria. Among these 115, we included all patients (n = 40) who underwent DWI within 24 hours from symptom onset (mean, 9.7 +/- 7.1 hours). All 40 patients also underwent magnetic resonance angiography and T2-weighted imaging. Seventy-five did not meet inclusion criteria: in 45, magnetic resonance imaging was performed more than 24 hours after symptom onset; 12 did not have DWI; in 11 patients, symptoms resolved within 24 hours; 6 had hemorrhages; and 1 had a border zone infarct. RESULTS: An acute lesion on DWI corresponding to the patient's symptoms was detected in all 40 patients, 16 (40%) of whom had detectable acute lesions on T2-weighted images. The lesions on DWI were larger in 11 of the 16 patients with positive T2-weighted images. Acute lesion volume did not correlate with NIHSS score (n = 40; rho = 0.30; P =.06, Spearman rank) also when DWI lesion volumes were divided by cause and territory. CONCLUSIONS: Diffusion-weighted imaging is more effective than T2-weighted imaging in patients with acute posterior-circulation strokes. The DWI lesion volume did not significantly correlate with NIHSS score, suggesting that NIHSS is more weighted toward anterior-circulation stroke symptoms.

Differences in stroke subtypes among natives and caucasians in Boston and Buenos Aires.

BACKGROUND AND PURPOSE: Several issues regarding ethnic-cultural factors, sex-related variation, and risk factors for stroke have been described in the literature. However, there have been no prospective studies comparing ethnic differences and stroke subtypes between populations from South America and North America. It has been suggested that natives from Buenos Aires, Argentina, may have higher frequency of hemorrhagic strokes and penetrating artery disease than North American subjects. The aim of this study was to validate this hypothesis. METHODS: We studied the database of all consecutive acute stroke patients admitted to the Ramos Mejia Hospital (RMH) in Buenos Aires and to the Beth Israel Deaconess Medical Center (BIMC) in Boston, Massachusetts, from July 1997 to March 1999. Stroke subtypes were classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. All information on patients (demographic, clinical, and radiographic) was recorded prospective to the assessment of the stroke subtype. RESULTS: Three hundred sixty-one and 479 stroke patients were included at RMH and BIMC stroke data banks, respectively. Coronary artery disease was significantly more frequent in BIMC (P:<0.001), whereas tobacco and alcohol intake were significantly more frequent in RMH (P:<0.001). Intracerebral hemorrhage (P:<0.001) and penetrating artery disease (P:<0.001) were significantly more frequent in the RMH registry, whereas large-artery disease (P:<0.02) and cardioembolism (P:<0.001) were more common in the BIMC data bank. CONCLUSIONS: Penetrating artery disease and intracerebral hemorrhage were the most frequent stroke subtypes in natives from Buenos Aires. Lacunar strokes and intracerebral hemorrhage were more frequent among Caucasians from Buenos Aires than Caucasians from Boston. Poor risk factor control and dietary habits could explain these differences.

MRI features of intracerebral hemorrhage within 2 hours from symptom onset.

BACKGROUND AND PURPOSE: MRI has been increasingly used in the evaluation of acute stroke patients. However, MRI must be able to detect early hemorrhage to be the only imaging screen used before treatment such as thrombolysis. Susceptibility-weighted imaging, an echo-planar T2* sequence, can show intracerebral hemorrhage (ICH) in patients imaged between 2.5 and 5 hours from symptom onset. It is unknown whether MRI can detect ICH earlier than 2.5 hours. We describe 5 patients with ICH who had MRI between 23 and 120 minutes from symptom onset and propose diagnostic patterns of evolution of hyperacute ICH on MRI. METHODS: As part of our acute imaging protocol, all patients with acute stroke within 24 hours from symptom onset were imaged with a set of sequences that included susceptibility-weighted imaging, diffusion- and perfusion-weighted imaging, T1- and T2-weighted imaging, fluid-attenuated inversion recovery (FLAIR), and MR angiography using echo-planar techniques. Five patients with ICH had MRI between 23 and 120 minutes from the onset of symptoms. RESULTS: ICH was identified in all patients. Distinctive patterns of hyperacute ICH and absence of signs of ischemic stroke were the hallmark features of this diagnosis. The hyperacute hematoma appears to be composed of 3 distinct areas: (1) center: isointense to hyperintense heterogeneous signal on susceptibility-weighted and T2-weighted imaging; (2) periphery: hypointense (susceptibility effect) on susceptibility-weighted and T2-weighted imaging; and (3) rim: hypointense on T1-weighted imaging and hyperintense on T2-weighted imaging, representing vasogenic edema encasing the hematoma. CONCLUSIONS: MRI is able to detect hyperacute ICH and show a pattern of evolution of the hematoma within 2 hours from the onset of symptoms.

Moyamoya disease in Italian monozygotic twins.

We report white monozygotic twins with moyamoya disease (MMD) (adult ischemic type). Both had cerebral angiography, MRI, magnetic resonance angiography, SPECT, EEG, human leukocyte antigen (HLA) typing, evaluation of thrombophilia, and immunologic and karyotype analysis. The clinical features and HLA phenotypes described in Asian monozygotic twins with MMD were not found in our patients. However, genetic analysis revealed a homozygous state for C-->T (Ala-->Val substitution) in position 677 of the methylenetetrahydrofolate reductase-encoding gene.

Levodopa peak response time reflects severity of dopamine neuron loss in Parkinson's disease.

We measured the time to peak antiparkinson response following injection of levodopa or apomorphine in 57 patients with Parkinson's disease. The peak response time for levodopa fell from 53 +/- 6.5 minutes in patients at Hoehn and Yahr stage I-II, and 28 +/- 4.8 minutes in those at stage IV (p < 0.0005). There was a significant correlation between levodopa peak response time and symptom duration (r = 0.65; p < 0.0001), but there was no relation between apomorphine peak response time and measures of disease severity. Peak response time to levodopa appears to reflect predominantly the status of compensatory presynaptic dopaminergic mechanisms and thus may provide an index to the degree of dopamine neuron degeneration in parkinsonian patients.

Peripheral benzodiazepine receptors and glucose metabolism in human gliomas.

Peripheral benzodiazepine receptors (PBR) are increased in gliomas and augmented glucose metabolism is seen in malignant brain tumors. We investigated the relationship between PBR density (Bmax) and glucose utilization rate (GUR) in 17 patients with cerebral gliomas of different grades. PBR Bmax was assessed by [3H]PK-11195 in vitro binding in surgical specimens and GUR was measured by Positron Emission Tomography with [18F]2-Fluorodeoxyglucose before the surgery. In untreated tumors there was a positive correlation between PBR Bmax and GUR (2r = 0.84). This correlation was not observed in patients who had been treated with radiation and/or chemotherapy prior to surgery (r2 = 0.13). In addition, in untreated patients, the increase in PBR density and GUR appeared to be related to the degree of malignancy.

Histopathologic correlates of abnormal water diffusion in cerebral ischemia: diffusion-weighted MR imaging and light and electron microscopic study.

PURPOSE: To correlate the findings on diffusion-weighted magnetic resonance (MR) images with the cytologic and histologic findings in ischemic tissue. MATERIALS AND METHODS: A photochemical model of cerebral infarction in rats was studied with diffusion- and T2-weighted MR imaging. The development of lesions was followed from 20 minutes to 5 days after the onset of ischemia. Apparent water diffusion coefficient (ADC) maps were calculated and correlated with light and electron microscopic findings. RESULTS: T2-weighted images clearly showed vasogenic edema but did not enable distinction between areas with cellular damage and the surrounding edematous regions. In contrast, the ADC, which was elevated in nonischemic edematous regions, was diminished in areas with histologic evidence of ischemic damage or necrosis. In the core of the infarct, the ADC became elevated when electron microscopy revealed cellular lysis. CONCLUSION: Diffusion-weighted images may help ascertain the extent of cellular damage and death after stroke.