The cadaveric perfusion and angiography as a teaching tool: imaging the intracranial vasculature in cadavers.

Background and Study Aim To enhance the visualization of the intracranial vasculature of cadavers under gross examination with a combination of imaging modalities. Material and Methods A total of 20 cadaver heads were used to test two different perfusion techniques. First, fixed cadaver heads were perfused with water; second, fresh cadavers were perfused with saline and 10% formalin.

Aneurysm volume-to-ostium area ratio: a parameter useful for discriminating the rupture status of intracranial aneurysms.

Background: Slow or stagnant flow is a hemodynamic feature that has been linked to the risk of aneurysm rupture.

Objective: To assess the potential value of the ratio of the volume of an aneurysm to the area of its ostium (VOR) as an indicator of intra-aneurysmal slow flow and, thus, in turn, the risk of rupture.

Methods: Using a sample defined from internal databases, a retrospective analysis of aneurysm size, aspect ratio (AR), and VOR was performed on a series of 155 consecutive aneurysms having undergone 3-dimensional digital subtraction angiography as a part of their evaluation.

Radiation dose reduction in time-resolved CT angiography using highly constrained back projection reconstruction.

Recently dynamic, time-resolved three-dimensional computed tomography angiography (CTA) has been introduced to the neurological imaging community. However, the radiation dose delivered to patients in time-resolved CTA protocol is a high and potential risk associated with the ionizing radiation dose. Thus, minimizing the radiation dose is highly desirable for time-resolved CTA.

Frequency of thromboembolic events associated with endovascular aneurysm treatment: retrospective case series.

Object: There is little evidence addressing whether procedures requiring adjunctive devices lead to an increased frequency of thromboembolic complications. The authors report their experience with 155 aneurysms treated with and without adjunctive devices.

Methods: The authors retrospectively reviewed their last 155 aneurysm coil placement procedures.

Comparison of platinum and first-generation Matrix coils in under-packed canine side-wall aneurysms: evaluation of progressive thrombosis.

Introduction: There is much speculation in reference to the occurrence and mechanisms of progressive aneurysm occlusion after treatment with bioactive coils. However, to our knowledge, there are no studies documenting the impact on progressive occlusion in aneurysms that are intentionally under-packed.

Methods: A total of 24 experimental side-wall aneurysms were created in canine common carotid arteries.

Variability of clinical CT perfusion measurements in patients with carotid stenosis.

Introduction: CT perfusion imaging (pCT) may be used to detect and monitor hemodynamic abnormalities due to cerebrovascular disease. The magnitude of variability in clinical measurements has been insufficiently evaluated. The purpose of this study was to measure the long-term variability of clinical pCT measurements in patients with cerebrovascular disease.

Evaluation of cerebral hemodynamics with computed tomography perfusion using gadolinium as an alternative to iodinated contrast: a case report.

Computed tomography (CT) perfusion is traditionally performed using iodinated contrast, but this can be problematic in patients with impaired renal function or contrast allergy. We report a case of a 63-year-old man whose medical history was complicated by chronic renal failure, which was exacerbated after placement of a left cervical internal carotid artery stent by 70% stenosis and left hemisphere perfusion deficit. On a follow-up clinic visit, because of the patient s chronic renal failure, CT perfusion was performed successfully using gadolinium without further renal complications.

Experimental estimates of the constants relating signal change to contrast concentration for cerebral blood volume by T2* MRI.

Estimates of cerebral blood volume (CBV) obtained from dynamic contrast T2(*)-weighted magnetic resonance imaging (MRI) tend to be significantly higher than values obtained by other methods. This may relate to the common assumption that the proportionality constants relating signal change to contrast concentration are equal in tissue and artery. To test this hypothesis and provide estimates for the ratio of those proportionality constants, the authors compared measurements of CBV by both MRI and computed tomography (CT) scans in nine healthy volunteers obtained using identical kinetic paradigms for the two imaging modalities.