middle cerebral artery (mca)  (SAS institute)

Journal: Neurosurgery

Article Title: Utilization of Cone-Beam Computed Tomographic Angiography in Planning for Gamma Knife Radiosurgery of Arteriovenous Malformations: A Case Series and Early Report

doi: 10.1227/NEU.0000000000000331

Figure Lengend Snippet: A 61-year old female presented with a right parietal hemorrhage, generalized tonic clonic seizure, and left hemiparesis. She was found to harbor an AVM at the site of hemorrhage and was treated with GKR 1 month after presentation. Several diagnostic cerebral angiogram images are presented. A.) Anterio-posterior (AP) projection of an internal carotid artery (ICA) injection. Poor detailed arterial, nidal, and venous resolution of the AVM are noted (White arrow). B.) Anterio-posterior (AP) projection of a selective middle cerebral artery (MCA) injection. Poor detailed arterial, nidal, and venous resolution of the AVM are noted (White arrow). C.) 3DRA right ICA injection with a right parietal AVM (white arrow) but with continued limited arterial, nidal, and venous anatomy. D.) Axial CBCT-A reconstruction with patient in the Leksell head frame. The anterior posts and posterior pins of the frame are seen. A right parietal AVM is visualized. E.) Magnified axial CBCT-A reconstruction. Excellent resolution of the complex arterial and venous structure of the AVM are noted (White arrow). F.) Screen shot image of a coronal CBCT-A reconstruction uploaded for planning on the Leksell stereotactic planning computer. The radiated field is demonstrated by the encircled areas at different radiation isodoses. Note that the draining vein is easily resolved and left out of the radiation field (White arrow). G.) 2-year follow-up AP projection of an ICA injection demonstrating complete obliteration of the previously seen AVM. H.) 2-year follow-up magnified axial CBCT-A reconstruction demonstrating complete obliteration of the previously seen AVM.

Article Snippet: Anterio-posterior (AP) projection of a selective middle cerebral artery (MCA) injection.

Techniques: Diagnostic Assay, Injection

Journal: Acta physiologica (Oxford, England)

Article Title: Cardiovascular function in the heat-stressed human

doi: 10.1111/j.1748-1716.2010.02119.x

Figure Lengend Snippet: End-tidal carbon dioxide tension and middle cerebral artery blood velocity (MCA Vmean) during normothermia, heat stress, and heat stress after end-tidal carbon dioxide (PETCO2) concentration was returned to pre-heat stress levels. The reduction in PETCO2 concentration during heat stress was completely abolished by the PETCO2 clamping procedure (panel a). Heat stress reduced MCA Vmean relative to normothermia. Restoration of PETCO2 to the normothermic level while subjects were heat stressed (heat stress + clamp) attenuated the decrease in MCA Vmean relative to control heat stress without the clamp; however MCA Vmean remained reduced when compared with normothermia (panel b). These data indicate that mechanisms other than reduced PETCO2 contribute to the reduced cerebral perfusion that occurs in heat-stressed individuals. *Significantly different relative to normothermia; §significantly different relative to control heat stress. Figure from Brothers et al. (2009b); republished with permission from Wiley-Blackwell.

Article Snippet: Therefore, it is plausible to speculate that heat stress-induced increases in cerebral sympathetic activity may contribute to reductions in cerebral perfusion in the heat-stressed human. fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window Figure 5 caption a7 End-tidal carbon dioxide tension and middle cerebral artery blood velocity (MCA V mean ) during normothermia, heat stress, and heat stress after end-tidal carbon dioxide (PETCO 2 ) concentration was returned to pre-heat stress levels.

Techniques: Concentration Assay, Control

Journal: Acta physiologica (Oxford, England)

Article Title: Cardiovascular function in the heat-stressed human

doi: 10.1111/j.1748-1716.2010.02119.x

Figure Lengend Snippet: Cerebral circulation and oxygenation during maximal whole-body exercise in heat-stressed humans. Left and right middle cerebral artery blood velocity and near-infrared spectroscopy-determined cerebral tissue oxygenation at rest, during submaximal and maximal cycling and during 10 min of recovery in heat stress and control conditions. Note the marked reductions in blood velocity accompanying the declines in tissue oxygenation. *Higher than value at start of exercise, P < 0.05. †Lower than peak value during maximal exercise, P < 0.05. From González-Alonso et al. (2004); republished with permission from Wiley-Blackwell.

Article Snippet: Therefore, it is plausible to speculate that heat stress-induced increases in cerebral sympathetic activity may contribute to reductions in cerebral perfusion in the heat-stressed human. fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window Figure 5 caption a7 End-tidal carbon dioxide tension and middle cerebral artery blood velocity (MCA V mean ) during normothermia, heat stress, and heat stress after end-tidal carbon dioxide (PETCO 2 ) concentration was returned to pre-heat stress levels.

Techniques: Spectroscopy, Control