The anterior cerebral artery is an appropriate arterial input function for perfusion-CT processing in patients with acute stroke

Context: Recently, with the advance of neuroimaging modalities, the windows of reperfusion therapy in patients with acute stroke have been reviewed and extended, especially for mechanical thrombectomy. Case report: 81 year old patient, previously hypertensive and dyslipidemic, fully functional (modified Rankin scale = 0), admitted to the emergency room of a tertiary hospital with global aphasia, right hemiparesis, right homonymous hemianopsia and severe hypoesthesia of the right upper limb, scoring 26 on the NIHSS, with report of having contacted family members for the last time 15 hours before admission. She was treated according to the institution’s acute stroke protocol, and underwent non-contrast brain computed tomography (CT), perfusion CT with Rapid CT protocol and cerebral artery + neck angio-CT, which ruled out bleeding and showed an ASPECTS of 8, an estimated ischemic core volume of 17 mL, and an area with hypoperfusion of 118 mL (perfusional mismatch of 101 mL), besides occlusion of the M1 segment of the left middle cerebral artery. Thus, she was submitted to chemical thrombolysis, with a decrease in NIHSS score to 15 and evolving without complications upon hospitalization. Conclusions: In patients with uncertain ictus, the use of advanced neuroimaging modalities, such as perfusion tomography with Rapid CT protocol, may assist in the indication of reperfusion therapies safely.

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Optimal Location for Arterial Input Function Measurements near the Middle Cerebral Artery in First-Pass Perfusion MRI

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2008.155 ◽

2009 ◽

Vol 29 (4) ◽

pp. 840-852 ◽

Cited By ~ 46

Author(s):

Egbert JW Bleeker ◽

Mark A van Buchem ◽

Matthias JP van Osch

Keyword(s):

Middle Cerebral Artery ◽

Cerebral Artery ◽

Arterial Input Function ◽

Input Function ◽

Optimal Location ◽

Dynamic Susceptibility ◽

Planar Imaging ◽

Partial Volume ◽

Partial Volume Effects ◽

Volume Effects

One of the main difficulties in obtaining quantitative perfusion values from dynamic susceptibility contrast-magnetic resonance imaging is a correct arterial input function (AIF) measurement, as partial volume effects can lead to an erroneous shape and amplitude of the AIF. Cerebral blood flow and volume scale linearly with the area under the AIF, but shape changes of the AIF can lead to large, nonlinear errors. Current manual and automated AIF selection procedures do not guarantee the exclusion of partial volume effects from AIF measurements. This study uses a numerical model, validated by phantom experiments, for predicting the optimal location for AIF measurements in the vicinity of the middle cerebral artery (MCA). Three different sequences were investigated and evaluated on a voxel-by-voxel basis by comparison with the ground truth. Subsequently, the predictions were evaluated in an in vivo example. The findings are fourfold: AIF measurements should be performed in voxels completely outside the artery, here a linear relation should be assumed between Δ R*2 and the concentration contrast agent, the exact optimal location differs per acquisition type, and voxels including a small MCA yield also correct AIF measurements for segmented echo planar imaging when a short echo time was used.

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Acute Stroke due to Electrocution: Uncommon or Unrecognized?

Case Reports in Neurological Medicine ◽

10.1155/2016/9510863 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5

Author(s):

Laxmi Kokatnur ◽

Mohan Rudrappa

Keyword(s):

Acute Stroke ◽

Cerebral Artery ◽

Anterior Cerebral Artery ◽

Parietal Lobe ◽

Frontal Lobes ◽

Organ Damage ◽

Left Middle Cerebral Artery ◽

Anterior Circulation ◽

Daily Lives ◽

The Right

The growing dependence on electricity in our daily lives has increased the incidence of electrocution injuries. Although several neurological injuries have been described previously, acute stroke due to electrocution is rare. Our patient, a previously healthy man, was electrocuted after he grabbed a “live” high-voltage wire. Although he was hemodynamically stable, he remained confused with language defects. MRI of the brain showed acute stroke in the bilateral anterior cerebral artery territory and watershed regions of the left middle cerebral artery territory. MR angiogram incidentally showed A1 segment aplasia of the right anterior cerebral artery. Electrocution is known to cause vasospasm leading to end-organ damage similar to that seen in stroke. In our patient, vasospasm of the left anterior circulation likely led to watershed infarcts in the left parietal lobe and bilateral frontal lobes. Due to aplasia of the A1 segment on the right side, perfusion to both frontal lobes was solely from the left anterior cerebral artery.

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