Unilateral transverse sinus stenting of patients with idiopathic intracranial hypertension.

BACKGROUND AND PURPOSE: The pathophysiology of IIH remains unknown. TS stenoses have been observed in a high proportion of these patients. Stent placement to remove this potential obstruction to venous outflow has been proposed as a treatment option for patients with IIH refractory to medical treatment. MATERIALS AND METHODS: The clinical presentation, treatment, and outcome of patients with refractory IIH evaluated for venous sinus stent placement at a tertiary care center was retrospectively reviewed. RESULTS: Thirteen female patients with IIH were evaluated for sinovenous stent placement. Moderate sinus stenoses with normal intrasinus pressures were found in 3 patients and therefore stent placement was not performed. Ten patients had elevated intrasinus pressures (pressure gradient across stenosis, 11-50 mm Hg), which decreased following unilateral TS stent placement. Headaches improved or resolved in all stented patients. Papilledema resolved completely or almost completely in 8 patients and significantly improved in 2 patients. One patient developed optic atrophy. There were no major periprocedural complications. CONCLUSIONS: In this small case series, restoring the patency of stenotic venous sinuses with a stent in patients with refractory IIH resulted in symptomatic improvement in all treated patients. The safety and efficacy of this procedure should be evaluated in a randomized controlled study to determine its role within the armamentarium of therapeutic options for patients with IIH.

Intra-arterial thrombolysis of occluded middle cerebral artery by use of collateral pathways in patients with tandem cervical carotid artery/middle cerebral artery occlusion.

BACKGROUND AND PURPOSE: Cervical internal carotid artery (ICA) occlusion with middle cerebral artery (MCA) embolic occlusion is associated with a low rate of recanalization and poor outcome after intravenous thrombolysis. Prompt revascularization is required to prevent disabling stroke. We report our experience on acute ischemic stroke patients with tandem ICA or MCA occlusions treated with microcathether navigation and intra-arterial thrombolysis by use of collateral pathways including the posterior or anterior communicating arteries, or both pathways. MATERIALS AND METHODS: We retrospectively identified 8 patients with proximal ICA occlusion associated with MCA embolic occlusions treated with intra-arterial thrombolysis (IA rtPA). Access to the occluded MCA was obtained via catheter navigation through intact collateral pathways, including posterior communicating (PcomA) or anterior communicating (AcomA) arteries, without passing a microcathether through the acutely occluded ICA. We assessed clinical outcomes using modified Rankin scale (mRS) and National Institutes of Health Stroke Scale (NIHSS). RESULTS: Eight patients with a mean age of 57 +/- 4 years and median NIHSS of 14 were identified. Mean time from stroke onset to intra-arterial thrombolysis was 292 +/- 44 minutes. The MCA was revascularized completely in 5 of the 8 patients via collateral intra-arterial rtPA administration. All of the patients had a favorable outcome defined as a mRS of < or =2 or more at 1 and 3 months' follow-up after thrombolytic therapy. One patient had an asymptomatic petechial hemorrhage. CONCLUSION: In this small number of patients with tandem occlusions of the ICA and MCA, intra-arterial thrombolysis and recanalization of the MCA by use of collateral pathways to bypass the occluded ICA is a safe and efficacious therapeutic option.

Acute stroke with hyperdense middle cerebral artery sign benefits from IV rtPA.

OBJECTIVES: The current management of acute ischemic stroke is intravenous (IV) recombinant tissue plasminogen activator (rtPA). The presence of a hyperdense middle cerebral artery sign (HMCAS) on pre-treatment head computed tomogram (CT) is considered a poor prognostic sign. We compared the clinical outcome in IV rtPA-treated patients with and without a HMCAS. DESIGN: Retrospective analysis of prospectively collected cases treated with IV rtPA within three hours. Inclusion criteria were the presence of: i) an anterior circulation stroke; ii) a pre-treatment CT available; iii) a pre-treatment National Institutes of Health (NIH) stroke scale (NIHSS) score; and iv) a modified Rankin Score (mRS) at three months. RESULTS: One hundred and thirty patients were eligible for the analysis, 64 (49%) had a HMCAS. The HMCAS group had a trend toward a higher mean (+/-SD) pre-treatment NIHSS score compared to the non-HMCAS group (13.9+/-6 vs. 12.2+/-6; p=0.12). Accordingly, there were more patients with severe strokes (NIHSS>10) in the HMCAS group compared to the non-HMCAS one (48/64=75% vs. 35/66=53%; p=0.009). The mean (+/-SD) NIHSS score 24 hours after treatment was 10.6 (+/-8) in the HMCAS group and 8.3 (+/-7) in the non-HMCAS group (p=0.08). In a multiple logistic regression analysis, the only independent predictor of poor outcome (mRS 3-6) was pre-treatment NIHSS score (p<0.001). CONCLUSION: Patients with a HMCAS receiving IV rtPA did not fare worse at three months despite a greater proportion of patients with more severe strokes. Based on the current knowledge, IV rtPA remains a good treatment for patients with a HMCAS within three hours of symptom onset.

Identification of penumbra and infarct in acute ischemic stroke using computed tomography perfusion-derived blood flow and blood volume measurements.

BACKGROUND AND PURPOSE: We investigated whether computed tomography (CT) perfusion-derived cerebral blood flow (CBF) and cerebral blood volume (CBV) could be used to differentiate between penumbra and infarcted gray matter in a limited, exploratory sample of acute stroke patients. METHODS: Thirty patients underwent a noncontrast CT (NCCT), CT angiography (CTA), and CT perfusion (CTP) scan within 7 hours of stroke onset, NCCT and CTA at 24 hours, and NCCT at 5 to 7 days. Twenty-five patients met the criteria for inclusion and were subsequently divided into 2 groups: those with recanalization at 24 hours (n=16) and those without (n=9). Penumbra was operationally defined as tissue with an admission CBF <25 mL x 100 g(-1) x min(-1) that was not infarcted on the 5- to 7-day NCCT. Logistic regression was applied to differentiate between infarct and penumbra data points. RESULTS: For recanalized patients, CBF was significantly lower (P<0.05) for infarct (13.3+/-3.75 mL x 100 g(-1) x min(-1)) than penumbra (25.0+/-3.82 mL x 100 g(-1) x min(-1)). CBV in the penumbra (2.15+/-0.43 mL x 100 g(-1)) was significantly higher than contralateral (1.78+/-0.30 mL x 100 g(-1)) and infarcted tissue (1.12+/-0.37 mL x 100 g(-1)). Logistic regression using an interaction term (CBFxCBV) resulted in sensitivity, specificity, and accuracy of 97.0%, 97.2%, and 97.1%, respectively. The interaction term resulted in a significantly better (P<0.05) fit than CBF or CBV alone, suggesting that the CBV threshold for infarction varies with CBF. For patients without recanalization, CBF and CBV for infarcted regions were 15.1+/-5.67 mL x 100 g(-1) x min(-1) and 1.17+/-0.41 mL x 100 g(-1), respectively. CONCLUSIONS: We have shown in a limited sample of patients that CBF and CBV obtained from CTP can be sensitive and specific for infarction and should be investigated further in a prospective trial to assess their utility for differentiating between infarct and penumbra.

Neurovascular radiosurgery.

SUMMARY: This article focuses on the treatment of neurovascular diseases, in particular brain arteriovenous malformations (BAVMs), with radiosurgery. The target group for this review is physicians who manage patients with neurovascular diseases, but are not actively engaged in radiosurgery. Radiosurgery for BAVMs is an established treatment with clearly defined risks and benefits. The efficacy of radiosurgery for dural arteriovenous shunts (DAVSs) is probably similar but the treatment has not yet gained the same acceptance. Radiosurgical treatment of cavernomas (cavernous hemangiomas) remains controversial. Well founded predictive models for BAVM radiosurgery show: * The probability of obliteration depends on the dose of radiation given to the periphery of the BAVM. * The risk of adverse radiation effects depends on the total dose of radiation, i.e. the amount of energy imparted into the tissue. The risk is greater in centrally located lesions. The risk of damage to brainstem nucleii and cranial nerves must be added to the risk predicted from current outcome models. * The risk of hemorrhage during the time span before obliteration depends on the BAVM volume, the dose of radiation to the periphery of the lesion and the age of the patient. Central location is a probably also a risk factor.

Combined endovascular/neurosurgical therapy of blister-like distal internal carotid aneurysms.

OBJECTIVE: To describe a novel therapeutic strategy for the treatment of "blister-like" aneurysms of the distal internal carotid artery (ICA). Direct surgical treatments of these fragile lesions have been associated with generally poor outcomes. METHODS: Two consecutive patients presenting with acute subarachnoid hemorrhage from "blister-like" aneurysms were treated with preliminary balloon occlusion of the ICA, followed by surgical trapping of the ICA beyond the aneurysm. RESULTS: The treatment resulted in complete thrombosis of both aneurysms with no clinical complications. CONCLUSION: This combined endovascular-neurosurgical approach offers a controlled, safer alternative to primary surgical therapy of "blister-like" aneurysms.

Carotid stenting without angioplasty.

BACKGROUND: Carotid angioplasty and stenting is gaining popularity as an alternative to carotid endarterectomy for the treatment of carotid bifurcation stenosis. The major concern with the procedure is the risk of embolic stroke which may be initiated by balloon angioplasty of friable atherosclerotic plaque. Elimination of angioplasty may result in a lower incidence of embolic complications. METHOD: We describe a case in which a self-expanding stent alone, without balloon angioplasty, was used to successfully dilate an atherosclerotic stenosis of the carotid bifurcation. RESULTS: A moderate increase in vessel diameter, from 75% to 50%, was immediately observed after stent placement alone. No embolic complications were observed and follow-up plain film and ultrasound examinations showed progressive stent enlargement with excellent anatomic and hemodynamic results. CONCLUSIONS: In this case of severe carotid stenosis, the use of a self-expanding stent alone, without balloon angioplasty, resulted in excellent anatomic and hemodynamic improvement.

Endovascular treatment of a lenticulostriate artery aneurysm with N-butyl cyanoacrylate.

BACKGROUND: Aneurysms arising from lenticulostriate artery branches in moyamoya-type disease are challenging lesions to treat, due to their fragility and deep location. Surgery is difficult and endovascular options may be limited. METHODS: A 57-year-old woman presented with a right ganglionic parenchymal hemorrhage due to a ruptured lenticulostriate artery aneurysm associated with ipsilateral middle cerebral artery occlusion. The aneurysm and parent feeding artery were occluded using endovascular injection of N-butyl cyanoacrylate. RESULTS: The aneurysm was successfully obliterated and although some glue did enter the more distal middle cerebral artery, there was no change in the patient's neurologic status. CONCLUSIONS: In highly selected cases where lenticulostriate aneurysms cannot be directly accessed for surgery or endovascular coiling, obliteration with liquid acrylic glue may be considered as a therapeutic option.