AJNR. American journal of neuroradiology
-
AJNR Am J Neuroradiol · Apr 2010
Optimal brain perfusion CT coverage in patients with acute middle cerebral artery stroke.
PCT has emerged as an alternative to MR imaging for the assessment of patients with suspected acute stroke. However, 1 disadvantage of PCT is its limited anatomic coverage, which may impact the characterization of hemispheric ischemic strokes. The purpose of this study was to determine the optimal brain CT coverage required to accurately estimate the size of the infarct core relative to the MCA territory and the infarct-penumbra mismatch, by using a criterion standard of these parameters measured on PCT with 80-mm z-axis coverage. ⋯ Seventy-five millimeters is the minimal PCT coverage required to use PCT as a tool to select patients with acute stroke for reperfusion therapy by using a mismatch of 0.5. A z-axis coverage of 50 mm was sufficient for a mismatch of 0.2; and 55 mm, for the size of PCT infarct relative to MCA territory (one-third or more).
-
AJNR Am J Neuroradiol · Apr 2010
Quantification of diffusivities of the human cervical spinal cord using a 2D single-shot interleaved multisection inner volume diffusion-weighted echo-planar imaging technique.
DTI is a highly sensitive technique, which can detect pathology not otherwise noted with conventional imaging methods. This paper provides the atlas of reliable normative in vivo DTI parameters in the cervical spinal cord and its potential applications toward quantifying pathology. ⋯ DTI using 2D ss-IMIV-DWPEI is sensitive to spinal cord pathology. This technique can be used to detect and quantify the degree of pathology within the cervical spinal cord from multiple disease states.
-
AJNR Am J Neuroradiol · Apr 2010
Comparative StudyIn vitro evaluation of MR imaging issues at 3T for aneurysm clips made from MP35N: Findings and information applied to 155 additional aneurysm clips.
Aneurysm clips need to be tested at 3T to characterize MR imaging concerns, including magnetic field interactions, MR imaging-related heating, and artifacts. Therefore, we evaluated these risks for aneurysm clips. ⋯ The results of this investigation demonstrated that it would be acceptable (ie, "MR conditional" using current terminology) for patients with these aneurysm clips to undergo MR imaging at < or =3T. Notably, on the basis of the sizes of the clips that underwent testing, these findings pertain to 155 additional aneurysm clips made from the same material.
-
AJNR Am J Neuroradiol · Apr 2010
Utility of CT angiography in the identification and characterization of supraclinoid internal carotid artery blister aneurysms.
Blister aneurysms of the supraclinoid ICA represent a rare but potentially catastrophic cause of SAH, often presenting both diagnostic and therapeutic dilemmas. We explore the utility of CTA in the identification and characterization of ICA blister aneurysms. ⋯ In the presence of SAH and otherwise negative findings on CTA, a catheter cerebral angiogram should be performed to absolutely exclude an ICA blister aneurysm.
-
AJNR Am J Neuroradiol · Apr 2010
Case ReportsNegative CT angiography findings in patients with spontaneous subarachnoid hemorrhage: When is digital subtraction angiography still needed?
CTA is becoming the frontline modality to reveal aneurysms in patients with SAH. However, in about 20% of SAH patients no aneurysm is found. In these cases, intra-arterial DSA is still performed. Our aim was to evaluate whether negative findings on CTA can reliably exclude aneurysms in patients with acute SAH. ⋯ In patients with SAH, negative CTA findings are reliable in ruling out aneurysms in the PMH pattern or no blood on CT. DSA is indicated in the diffuse aneurysmal pattern of SAH, and repeat delayed DSA is required if the initial DSA findings are negative. When the blood is peripheral, CTA should be scrutinized for vasculitis and DSA is recommended for confirmation.