Local Cerebral Blood Flow Measured by Xenon-Enhanced CT during Cryogenic Brain Edema and Intracranial Hypertension in Monkeys

We developed a closed-skull model of freeze injury-induced brain edema, a model classically thought to produce vasogenic edema, and observed the natural course of changes in edema and blood flow using xenon-enhanced computed tomography (CT) in five rhesus monkeys before and for up to 6 h post insult. Intracranial pressure (ICP) gradually rose throughout the duration of the experiment. CT scans and CBF images permitted direct observation of the evolution of the lesion and revealed early ischemia in the periphery of the injury zone that progressed over time in association with edema. Frequency histogram analysis of local CBF (lCBF) demonstrated subtle but potentially important changes in distribution of lCBF between and within hemispheres at various times post insult. Changes in lCBF distribution were phasic and dissociated from increases in ICP in the latter stages of injury. The Xe/CT CBF method can be used to evaluate the effects of injury and therapy on CBF in this and other models of acute brain injury.

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The Effect of Contrast-enhanced Computed Tomography (CT) Scans on the Calculated Dose of Radiotherapy in a Thorax Phantom

International Journal of Cancer Management ◽

10.5812/ijcm.84158 ◽

2021 ◽

Vol In Press (In Press) ◽

Author(s):

Athar Ehtiati ◽

Payman Hejazi ◽

Mohsen Bakhshandeh ◽

Ali Jabbary Arfaee ◽

Eftekhar Rajab Bolookat ◽

...

Keyword(s):

Computed Tomography ◽

Contrast Media ◽

Ct Scan ◽

Treatment Planning ◽

Tumor Volume ◽

Ct Scans ◽

Contrast Enhanced ◽

Enhanced Ct ◽

Enhanced Computed Tomography ◽

Contrast Enhanced Computed Tomography

Background: Despite the benefits of contrast-enhanced computed tomography (CT) scans in better tumor volume delineation, it can affect the accuracy of dose calculation in radiation therapy. This study examined this effect on a thorax phantom. Objectives: The influence of different variables including the concentrations of the Visipaque contrast media, tumor sizes, and CT scan energies on the dose measurement was examined. Methods: Transparent cylinders containing the contrast media were inserted in the lung area of the phantom and the CT scans were made. Non-enhanced CT scans were also acquired. Treatment planning using 2 opposite fields was performed on the CT scans and the doses were calculated in the treatment planning system. The results of the 2 sets of enhanced and non-enhanced CT scans were compared. Results: The correlation between concentration and the percentage of mean dose of the tumor volume was significant in 2 of the tumor sizes. The differences in the mean doses of the 2 plans were examined and more than 3% increase was observed in higher concentrations of the contrast media. Conclusions: According to this study, the suitable concentration of the contrast media administered and the CT scan energy should be considered. This would help to decrease the discrepancies between the calculated and delivered dose in radiotherapy treatments to a clinically acceptable level. The importance of time delays for CT scans after administration of the contrast media is emphasized.

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Progress in cerebrovascular disease: local cerebral blood flow by xenon enhanced CT.

Stroke ◽

10.1161/01.str.13.6.750 ◽

1982 ◽

Vol 13 (6) ◽

pp. 750-758 ◽

Cited By ~ 75

Author(s):

D Gur ◽

S K Wolfson ◽

H Yonas ◽

W F Good ◽

L Shabason ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebrovascular Disease ◽

Local Cerebral Blood Flow ◽

Enhanced Ct

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Experimental focal ischemia in cats: changes in multimodality evoked potentials as related to local cerebral blood flow and ischemic brain edema.

Stroke ◽

10.1161/01.str.18.1.188 ◽

1987 ◽

Vol 18 (1) ◽

pp. 188-194 ◽

Cited By ~ 25

Author(s):

K Kataoka ◽

R Graf ◽

G Rosner ◽

W D Heiss

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Evoked Potentials ◽

Brain Edema ◽

Focal Ischemia ◽

Local Cerebral Blood Flow ◽

Ischemic Brain ◽

Ischemic Brain Edema ◽

Multimodality Evoked Potentials

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Local Cerebral Blood Flow and Glucose Metabolism in Hydrostatic Brain Edema

Neurologia medico-chirurgica ◽

10.2176/nmc.33.139 ◽

1993 ◽

Vol 33 (3) ◽

pp. 139-145 ◽

Cited By ~ 4

Author(s):

Hitoshi UMEZAWA ◽

Katsuji SHIMA ◽

Hiroo CHIGASAKI ◽

Shozo ISHII

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Glucose Metabolism ◽

Brain Edema ◽

Local Cerebral Blood Flow

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Intracerebral steal phenomenon induced focal reversible vasogenic edema and decrease in cerebral blood flow after carotid endarterectomy

Surgical Neurology International ◽

10.25259/sni_508_2019 ◽

2020 ◽

Vol 11 ◽

pp. 161

Author(s):

Yu Shimizu ◽

Katsuhiro Tsuchiya ◽

Norihiro Fujisawa

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Carotid Endarterectomy ◽

Brain Edema ◽

Vasogenic Edema ◽

Rare Complication ◽

Cerebral Hypoperfusion ◽

Radical Scavenger ◽

Steal Phenomenon ◽

Bilateral Carotid

Background: Intracerebral steal phenomenon (ISP) is a rare complication following surgical treatment of carotid stenosis. However, the factors responsible remain unknown. We described the rear case of the ISP who had vasogenic edema and cerebral blood flow (CBF) decline and presented with hemiparesis after carotid endarterectomy (CEA). Case Description: A 72-year-old male with stenosis of the bilateral carotid artery (NASCET right 90% and left 70%) presented with cerebral hypoperfusion manifesting as right hemiparesis, after left CEA. Fluid-attenuated inversion recovery images showed edema of the motor area around an old infarction and a decrease in CBF. This lesion was an area of vasogenic edema caused by ISP and focal cerebral hypoperfusion. CBF of the contralateral cerebral hemispheres had increased. The treatment with an intravenous infusion of a free radical scavenger and glycerol improved the patient’s symptoms and brain edema. Magnetic resonance imaging showed a gradual decline in the brain edema, which completely disappeared 2 weeks after CEA. He was discharged with no neurological deficit. Conclusion: In this report, we described the case of a patient with ISP who had vasogenic edema induced by CBF decline and presented with hemiparesis following CEA. This is the first report of progressing focal vasogenic edema caused by ISP after endarterectomy.

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