S Moskowitz

The versatile distal access catheter: The Cleveland clinic experience

BACKGROUND:Vascular access is fundamental to any endovascular intervention. Concentric Medical has developed the Outreach Distal Access Catheter (DAC), which affords stable access at the target vessel modulating the forces at play within the thrombectomy device complex. The DAC is a device with novel access characteristics useful in a host of other types of clinical scenarios. OBJECTIVE:To review our experience with the DAC family of devices, the theory, and method of use. METHODS:A retrospective review of all cases in which the DAC was used during the period 2008 to 2010 was conducted and the cases classified by indication. Catheter-related complications were recorded. The use of the DAC in a variety of settings including intracranial stenting, aneurysm coil embolization, and arteriovenous malformation embolization is described. RESULTS:The DAC was used in 103 procedures performed in 93 patients between August 2008 and February 2010. Indications included acute stroke, treatment of intracranial atherosclerosis, vasospasm therapy, arteriovenous malformation embolization, and aneurysm embolization. In those procedures, 113 catheters were used. No complications directly attributable to DAC use were identified. CONCLUSION:The DAC is useful for gaining access to the cerebral vasculature, especially in patients with significant tortuosity or when re-access of distal vasculature is required multiple times.

An Analysis of Inflation Times During Balloon-Assisted Aneurysm Coil Embolization and Ischemic Complications

Background and Purpose— The introduction of balloon remodeling has revolutionized the approach to coiling of wide-neck aneurysms. We studied the effects of balloon inflation during coil embolization on ischemic complications. Methods— A retrospective review was undertaken of the most recent 147 patients undergoing balloon remodeling for unruptured intracranial aneurysm coil embolization at a single institution (81 balloon, 66 unassisted). All underwent postprocedural MRI. Results— Among patients in the “balloon” group, the mean total inflation time was 18 minutes (range, 1–43), a mean number of inflations of 4 (range, 1–9), a mean maximum single inflation time of 7 minutes (range, 1–19), a mean reperfusion time of 2.2 minutes between inflations, and an average procedure time of 2 hours and 10 minutes. Asymptomatic diffusion-weighted imaging abnormalities were detected on postprocedural MRI in 21.5% of patients and symptomatic lesions were identified in 3.8%. Both silent and symptomatic ischemic rates were similar in the internal control group. Patients with ischemic findings were older and more likely have diabetes; no differences were found with respect to total balloon inflation time, number of inflations, maximum inflation time, or reperfusion times. Conclusions— We found no significant relationship between balloon inflation practices and ischemic events. Older and diabetic patients were more likely to have ischemic events develop.

Role of MIB1 in Predicting Survival in Patients with Glioblastomas

SummaryBackground: Histologic immunomarkers of cell cycle proteins have been utilized for prognosis in high-grade astrocytic tumors. One such marker, MIB1, an antibody immunoreactive throughout the cell cycle, is predictive of more aggressive disease and poorer prognosis in astrocytomas. An independent role of MIB1 analysis for survival prediction and clinical management within histologic grades has not been clearly proven. Methods: This study retrospectively evaluated MIB1 reactivity in tissue samples from 116 patients with glioblastomas on initial medical presentation. Clinical variables considered included gender, age, Karnofsky Performance Scores (KPS), extent of surgical resection, adjuvant radiation and survival. Results: Univariate and multivariate analyses were used to correlate these variables with MIB1 staining. MIB1 staining does not predict overall survival or response to adjuvant therapy as an independent risk factor. Conclusion: MIB1 labeling does not predict patient survival as an independent variable and does not predict response to additional therapies. Patient survival with glioblastoma was predicted by KPS, age, extent of resection and use of adjuvant radiotherapy.

Endovascular therapy of very small aneurysms of the anterior communicating artery: five-fold increased incidence of rupture.

BACKGROUND:Intraprocedural rupture is a dangerous complication of endovascular treatment. Small ruptured anterior communicating artery (ACoA) aneurysms and microaneurysms present a challenge for both surgical and endovascular therapies to achieve obliteration. An understanding of the complication rates of treating ruptured ACoA microaneurysms may help guide therapeutic options. OBJECTIVE:To report the largest cohort of ACoA microaneurysms treated with endovascular therapy over the course of the past 10 years. METHODS:We performed a retrospective review of 347 ACoA aneurysms treated in 347 patients at Cleveland Clinic and Emory University over a 10-year period. Patient demographics, aneurysmal rupture, size, use of balloon remodeling, patient outcomes, intraprocedural rupture, and rerupture were reviewed. RESULTS:Rupture rates were examined by size for all patients and subgroups and dichotomized to evaluate for size ranges associated with increased rupture rates. The highest risk of rupture was noted in aneurysms less than 4 mm. Of 347 aneurysms, 74 (21%) were less than 4 mm. The intraprocedural rupture rate was 5% (18/347) for ACoA aneurysms of any size. There was an intraprocedural rupture rate of 2.9% (8/273) among ACoA aneurysms greater than 4 mm compared with 13.5% (10/74) in less than 4-mm aneurysms. Procedural rupture was a statistically significant predictor of modified Rankin score after adjusting for Hunt and Hess grades (HH). CONCLUSION:ACoA aneurysms less than 4 mm have a 5-fold higher incidence of intraprocedural rerupture during coil embolization. Outcome is negatively affected by intraprocedural rerupture after adjusting for HH grade.

Posterior circulation flow diversion: a single-center experience and literature review

Background Flow diverters have been used predominantly for large anterior circulation aneurysms. Data on the safety and efficacy of this treatment for posterior circulation aneurysms are limited. Objective To present our posterior circulation flow diverter experience, outcomes and morbidity in comparison with recent studies. Methods A retrospective chart and imaging review of six patients with seven aneurysms in posterior circulation vessels, treated with flow diverter technology was carried out. A literature review was performed using standard online search tools. Results We included five saccular and two fusiform posterior circulation aneurysms. An average of two flow diverters was placed for each patient. Adjunctive coiling was used in three cases. Follow-up at an average of 14.5 months showed complete angiographic occlusion in 4 (57.1%) cases, including one patient with in-stent thrombosis and major brainstem stroke at 4.5 months, a week after self-discontinuing dual antiplatelet therapy. Two other patients developed small periprocedural strokes but had excellent recovery. One death occurred 18 months after the initial procedure. No aneurysm rupture or parenchymal hemorrhage was seen. Overall, 5 (71%) cases, all with saccular aneurysms, had good clinical outcome (modified Rankin score (mRS) 0–1). Fusiform basilar aneurysms had markedly worse outcomes (mRS 5 and 6). Our literature review yielded six other studies with 100 additional patients. Overall, good outcome was seen in 74.3%, with a 12.3% average mortality and 11% permanent neurologic deficit rate. Complete occlusion varied from 43% to 100%. Conclusions Flow diversion may be a possible treatment in carefully selected patients with high-risk atypical posterior circulation aneurysms, with poor natural history and no optimal treatment strategy. Symptomatic and fusiform large aneurysms appear to carry the highest risk. Further studies are necessary to assess the role of flow diversion in the posterior circulation.

Thromboembolic events associated with endovascular treatment of cerebral aneurysms

Objective To evaluate the rate of peri-procedural thromboembolic events after the endovascular treatment of cerebral aneurysms. The rate of diffusion-positive lesions was assessed in relation to selected procedural and technical factors. Methods 184 patients treated with coil embolization (198 total procedures) between July 2004 and February 2007 were included. In 65, the procedure was coiling alone; in 55, coiling with balloon remodeling; in 48, coiling with Neuroform stenting; and in 30, coiling, Neuroform stenting and balloon remodeling. All patients underwent a routine diffusion weighted magnetic resonance imaging (DWI) within the 72 h after the intervention for the detection of ischemic complications. Results Regardless of the technique used, thromboembolic complications were more common (p<0.0001) in patients with ruptured aneurysms (33/65, 51%) than in those with unruptured aneurysms (40/133, 30%). Balloon remodeling tended to be associated with a lower rate of DWI positivity than the other techniques. Younger patients (≤60) with unruptured aneurysms had the lowest rates of DWI lesions regardless of the technique used. Conclusion In this study, peri-procedural DWI-positive lesions occurred in approximately one-third of all cases. These were threefold more common in the setting of ruptured aneurysms. Adjunctive devices did not increase the rate of ischemic events. On the contrary, there was a trend toward fewer DWI abnormalities in the procedures in which balloon remodeling was employed. This may, in part, be related to the application of the conglomerate coil mass technique of balloon remodeling.

Comparison of techniques for stent assisted coil embolization of aneurysms

Introduction Stent assisted coiling (SAC) of aneurysms has been adopted with potential mechanical, hemodynamic and biologic properties imparting an advantage over coil embolization alone. The purpose of this investigation is to compare the various techniques of SAC at a single institution with regards to clinical, technical and angiographic complications and success. Methods Patients who underwent SAC between 2003 and 2010 were identified. Clinical charts, procedures, angiographic and non-invasive radiological images were analyzed to determine the anatomical and procedural details and adverse events. Immediate post-procedural angiograms as well as follow-up imaging were studied to assess the degree of aneurysm occlusion. Results 260 aneurysms were identified. The ‘coil through’ technique was employed in 37.3%, ‘balloon stent’ in 36.2%, ‘jailing’ in 10.8% and the ‘coil stent’ technique in 7.7%. Overall rate of adverse events was higher with the ‘coil stent’ and ‘jailing’ techniques compared with the ‘balloon stent’ technique. The ‘coil through’ technique was associated with a significantly lower packing density (31.4±20%) than all other techniques (‘coil stent’ 45.4±22%, ‘jailing’ 42.2±20%, ‘balloon stent’ 44.3±22%). Among ‘coil stent’ patients, an initial Raymond class 1 was achieved in 40%, compared with 57% of ‘jailing’, 28% of ‘coil through’ and 63% of ‘balloon stent’ cases. Conclusion Balloon assisted coil embolization followed by adjunctive stent deployment across the aneurysm neck appears to be the superior technique among stent assisted coiling methods at our institution. It combines a lower rate of thrombotic and coil related complications with a high rate of complete occlusion on initial and follow-up imaging.

Prehemorrhage statin use and the risk of vasospasm after aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE Aneurysmal SAH is often followed by delayed ischemic deficits attributable to cerebral vasospasm. Recent studies suggest a positive impact of statin therapy on the incidence of vasospasm. This study was designed to assess whether a history of prior use of statin therapy was associated with a lower risk of vasospasm in patients with SAH. METHODS We performed a comprehensive retrospective review of patients with aneurysmal SAH between 1997 and 2004. Clinical demographics and imaging data for all patients were reviewed, and a logistic regression analysis was performed to identify the predictors of cerebral vasospasm, defined as a combination of clinical signs with radiographic confirmation. RESULTS Three hundred eight patients were included. Mean age was higher in the group receiving statins (64 +/- 12 vs 54 +/- 12 years). Hunt and Hess scores and treatment modality were not significantly different between the groups. Vasospasm was observed in 31% of patients not taking a statin (n = 282) vs 23% taking a statin (n = 26), without achieving statistical significance. Discontinuation of the statin did not affect risk of vasospasm. CONCLUSIONS Use of a statin prior to an aneurysmal SAH trended to reduce the incidence of subsequent vasospasm, without achieving statistical significance.

POSTOPERATIVE COMPLICATIONS ASSOCIATED WITH DURAL SUBSTITUTES IN SUBOCCIPITAL CRANIOTOMIES

OBJECTIVE Dural replacements are used in cranial surgery when primary closure of native dura is not possible. The goal is to recreate a watertight barrier to prevent cerebrospinal fluid leakage with few associated complications. We reviewed a single-institution experience with a variety of dural substitutes in posterior fossa neurosurgery, for which higher complication rates are well described. METHODS Patients were screened for suboccipital posterior fossa neurosurgery between November 2005 and April 2007. Surgical logs were reviewed for diagnosis, procedure, and use of dural replacement. Clinical courses were reviewed for hydrodynamic complications, including delayed hydrocephalus, clinically significant pseudomeningocele, aseptic meningitis, and persistent cerebrospinal leakage. RESULTS One hundred twenty-eight patients were included, and a dural replacement was used in 106. Overall, the complication rate was 21.9% (28 patients). Complications were seen for acellular human dermis in 33.3%, for collagen matrix in the original formulation in 18.2%, for the reformulation in 16.9%, for the suturable formulation in 50%, for nonautologous materials in 24%, and for no dural replacement in 16.7%. Univariate and multivariate analysis demonstrated that hydrodynamic complications were associated with use of the suturable collagen matrix (odds ratio, 10.8; 95% confidence interval, 2.5–46.1; P = 0.0014) and trended with use of acellular human dermis (odds ratio, 4.6; 95% confidence interval, 0.9–23.1; P = 0.06). CONCLUSION The increased risk of hydrodynamic complications associated with suboccipital neurosurgery is modified by choice of dural replacement. Similar complication rates were seen for most materials with a variety of primary abnormalities, with the exception of suturable bovine collagen matrix, with hydrodynamic complications in 50% of patients.

Mycotic aneurysm detection rates with cerebral angiography in patients with infective endocarditis

Background Cerebral angiography remains the gold standard for the detection of mycotic aneurysms, and it has been estimated that ruptured mycotic aneurysms result in 5% of the neurological complications of patients with infective endocarditis (IE). Objective To determine the diagnostic yield of cerebral angiography in the above patient population and to assess patient factors that might suggest greater or lesser utility. Methods We retrospectively reviewed 168 patients who underwent cerebral angiography with a diagnosis of IE or infected left ventricular assist device at the Cleveland Clinic between January 2003 and March 2010 in accordance with institutional review board guidelines. Chart and imaging review was performed. Results 15/168 patients (8.9%) had mycotic aneurysms; 93.3% (14/15) of the patients with mycotic aneurysms presented with CNS hemorrhage and 66.7% (10/15) had acute ischemic findings. Of the 15 patients with mycotic aneurysms on angiography, seven underwent CT angiography and six underwent MR angiography, which showed mycotic aneurysms in three (42.9%) and two cases (one of which was questionable; 33.3%), respectively. Conclusions Patients with IE or similar sources of central bacterial emboli are prone to neurovascular complications. Approximately 9% of patients with IE at our institution who undergo cerebral angiography have mycotic aneurysms. Presentation with hemorrhage appears to be more predictive of aneurysm, as approximately 22% of patients with IE and hemorrhage were found to have an aneurysm compared with only 1% when hemorrhage was absent. Thus, patients with IE presenting with intracranial hemorrhage should undergo vascular imaging, preferably with cerebral angiography.