Purpose To evaluate the correlation between angiographic measures of Moyamoya disease and tissue-level impairment from measurements of tissue perfusion and cerebrovascular reactivity (CVR). Materials and Methods The relationship between perfusion-weighted arterial spin labeling (ASL) and hypercarbic blood oxygenation-level dependent (BOLD) CVR and time-to-peak (TTP) were compared with angiographically measured risk factors including arterial circulation time (ACT) and modified Suzuki Score (mSS) in patients (n=15) with Moyamoya disease. Results Hemodynamic contrasts provided information not apparent from structural or angiographic imaging. Mean z-statistics demonstrate that BOLD is significantly (P=0.017) higher in low mSS hemispheres (z-statistic=5.0±2.5) compared to high mSS hemispheres (z-statistic=3.7±1.7), implying that regions with less advanced stages of Moyamoya disease have higher reactivity. After correcting for multiple comparisons, a strong trend for a direct relationship (R=0.38; P=0.03) between BOLD TTP and ACT was observed, and a significant inverse relationship between CBF and ACT (R=−0.47; P=0.01) was found, demonstrating that BOLD and ASL contrasts reflect DSA measures of vascular compromise in Moyamoya disease, albeit with different sensitivity. Conclusion Correlative measures between angiography and hemodynamic methods suggest that BOLD and ASL could be used for expanding the diagnostic imaging infrastructure in Moyamoya patients and potentially tracking tissue response to revascularization.

Rupture of a cerebral arteriovenous malformation can result in devastating hemorrhage with a possibility of serious neurological injury or death. Endovascular embolization is an important adjunct in the treatment of cerebral arteriovenous malformations, and in a small number of cases may provide definitive treatment. Currently available embolic agents have several shortcomings, including the possibility of recanalization, adhesiveness to the endovascular microcatheter and suboptimal handling at the time of surgical resection. Onyx is an ethylene vinyl alcohol copolymer dissolved in dimethyl sulfoxide that was approved by the US FDA in July 2005 as an embolic agent for brain arteriovenous malformations. Although long-term follow-up is limited, this agent appears to offer several advantages over the other available embolic agents for the endovascular management of arteriovenous malformations and other vascular lesions.

'Vascular steal' has been proposed as a compensatory mechanism in hemodynamically compromised ischemic parenchyma. Here, independent measures of cerebral blood flow (CBF) and blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) responses to a vascular stimulus in patients with ischemic cerebrovascular disease are recorded. Symptomatic intracranial stenosis patients (n ¼ 40) underwent a multimodal 3.0T MRI protocol including structural (T 1 -weighted and T 2 -weighted fluidattenuated inversion recovery) and hemodynamic (BOLD and CBF-weighted arterial spin labeling) functional MRI during room air and hypercarbic gas administration. CBF changes in regions demonstrating negative BOLD reactivity were recorded, as well as clinical correlates including symptomatic hemisphere by infarct and lateralizing symptoms. Fifteen out of forty participants exhibited negative BOLD reactivity. Of these, a positive relationship was found between BOLD and CBF reactivity in unaffected (stenosis degreeo50%) cortex. In negative BOLD cerebrovascular reactivity regions, three patients exhibited significant (Po0.01) reductions in CBF consistent with vascular steal; six exhibited increases in CBF; and the remaining exhibited no statistical change in CBF. Secondary findings were that negative BOLD reactivity correlated with symptomatic hemisphere by lateralizing clinical symptoms and prior infarcts(s). These data support the conclusion that negative hypercarbia-induced BOLD responses, frequently assigned to vascular steal, are heterogeneous in origin with possible contributions from autoregulation and/or metabolism.

Angiographic roadmapping is an effective intraoperative navigation tool for resection of vascular lesions that has not been previously described and offers several advantages to frameless stereotaxy.

The authors report on the case of a 24-year-old man who presented with back pain and radiculopathy due to epidural venous engorgement in the setting of a congenitally absent inferior vena cava. Despite initial improvement after steroid administration, the patient's health ultimately declined over a period of weeks, and signs and symptoms of cauda equina syndrome manifested. Lumbar decompression was performed and involved coagulation and resection of the compressive epidural veins. No complications occurred, and the patient made a full neurological recovery.

The double injection technique, with marking pen demarcation of the nidus perimeter, venous drainage, and microcatheter tip position, was qualitatively useful in every case.

More frequently than adults, pediatric victims of severe traumatic brain injury experience diffuse severe cerebral edema without mass lesions. These patients require methods to reduce intracranial pressure quickly and reliably. Surgical decompression provides rapid relief of increased intracranial pressure and is an alternative to maximal medical therapy for these individuals. Based on previous trials, most of which are anecdotal but now include attempts at case controlled and cohort matched investigations, Ruf and colleagues describe a series of six pediatric patients treated with a prospectively implemented protocol of decompressive craniectomy for severe traumatic brain injury. The heterogeneous approaches presented (which include hemicraniectomy, bifrontal craniectomy, and suboccipital craniectomy) undermine the applicability of the results. However, this report, coupled with similar papers, does highlight the need for a true controlled trial of this modality to examine whether craniectomy can emerge as more than a second line option for the management of increased intracranial pressure.

Background:Based on numerous reports citing high sensitivity and specificity of non-invasive imaging [e.g. computed tomography angiography (CTA) or magnetic resonance angiography (MRA)] in the detection of intracranial aneurysms, it has become increasingly difficult to justify the role of conventional angiography [digital subtraction angiography (DSA)] for diagnostic purposes. The current literature, however, largely fails to demonstrate the practical application of these technologies within the context of a “real-world” neurosurgical practice. We sought to determine the proportion of patients for whom the additional information gleaned from 3D rotational DSA (3DRA) led to a change in treatment.Methods:We analyzed the medical records of the last 361 consecutive patients referred to a neurosurgeon at our institution for evaluation of “possible intracranial aneurysm” or subarachnoid hemorrhage (SAH). Only those who underwent non-invasive vascular imaging within 3 months prior to DSA were included in the study. For asymptomatic patients without a history of SAH, aneurysms less than 5 mm were followed conservatively. Treatment was advocated for patients with unruptured, non-cavernous aneurysms measuring 5 mm or larger and for any non-cavernous aneurysm in the setting of acute SAH.Results:For those who underwent CTA or MRA, the treatment plan was changed in 17/90 (18.9%) and 22/73 (30.1%), respectively, based on subsequent information gleaned from DSA. Several reasons exist for the change in the treatment plan, including size and location discrepancies (e.g. cavernous versus supraclinoid), or detection of a benign vascular variant rather than a true aneurysm.Conclusions:In a “real-world” analysis of intracranial aneurysms, DSA continues to play an important role in determining the optimal management strategy.