Dynamic Scan

To test the hypothesis that brain oxidative metabolism is significantly increased upon adequate stimulation, we varied the presentation of a visual stimulus to determine the frequency at which the metabolic response would be at maximum. The authors measured regional CMR O2 in 12 healthy normal volunteers with the ECAT EXACT HR+ (CTI/Siemens, Knoxville, TN, U.S.A.) three-dimensional whole-body positron emission tomograph (PET). In seven successive activating conditions, subjects viewed a yellow-blue annular checkerboard reversing its contrast at frequencies of 0, 1, 4, 8, 16, 32, and 50 Hz. Stimulation began 4 minutes before and continued throughout the 3-minute dynamic scan. In the baseline condition, the subjects began fixating a cross hair 30 seconds before the scan and continued to do so for the duration of the 3-minute scan. At the start of each scan, the subjects inhaled 20 mCi of 15O-O2 in a single breath. The CMR O2 value was calculated using a two-compartment, weighted integration method. Normalized PET images were averaged across subjects and coregistered with the subjects' magnetic resonance imaging in stereotaxic space. Mean subtracted image volumes (activation minus baseline) of CMR O2 then were obtained and converted to z statistic volumes. The authors found a statistically significant focal change of CMR O2 in the striate cortex (x = 9; y = −89; z = −1) that reached a maximum at 4 Hz and dropped off sharply at higher stimulus frequencies.

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68Ga-DOTANOC PET/CT mimicking renal dynamic scan: Lack of physiological uptake in the spleen of a newborn and the pituitary gland in congenital hyperinsulinism

Revista Española de Medicina Nuclear e Imagen Molecular ◽

10.1016/j.remn.2013.12.002 ◽

2014 ◽

Vol 33 (6) ◽

pp. 382-383

Author(s):

G. Kumar ◽

V.S. Dhull ◽

S. Karunanithi ◽

C. Bal ◽

R. Kumar

Keyword(s):

Pituitary Gland ◽

Congenital Hyperinsulinism ◽

Physiological Uptake ◽

Pet Ct ◽

Dynamic Scan

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Dynamic scan clock control for test time reduction maintaining peak power limit

29th VLSI Test Symposium ◽

10.1109/vts.2011.5783729 ◽

2011 ◽

Cited By ~ 12

Author(s):

Priyadharshini Shanmugasundaram ◽

Vishwani D. Agrawal

Keyword(s):

Peak Power ◽

Test Time ◽

Test Time Reduction ◽

Dynamic Scan ◽

Time Reduction ◽

Power Limit

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Dynamic Scan Procedure for Detecting Rare-Variant Association Regions in Whole Genome Sequencing Studies

10.1101/552950 ◽

2019 ◽

Author(s):

Zilin Li ◽

Xihao Li ◽

Yaowu Liu ◽

Jincheng Shen ◽

Han Chen ◽

...

Keyword(s):

Whole Genome Sequencing ◽

Genome Sequencing ◽

Rare Variant ◽

Type I Error ◽

Rare Variants ◽

Error Rates ◽

Type I ◽

Whole Genome ◽

Rare Variant Association ◽

Dynamic Scan

AbstractWhole genome sequencing (WGS) studies are being widely conducted to identify rare variants associated with human diseases and disease-related traits. Classical single-marker association analyses for rare variants have limited power, and variant-set based analyses are commonly used to analyze rare variants. However, existing variant-set based approaches need to pre-specify genetic regions for analysis, and hence are not directly applicable to WGS data due to the large number of intergenic and intron regions that consist of a massive number of non-coding variants. The commonly used sliding window method requires pre-specifying fixed window sizes, which are often unknown as a priori, are difficult to specify in practice and are subject to limitations given genetic association region sizes are likely to vary across the genome and phenotypes. We propose a computationally-efficient and dynamic scan statistic method (Scan the Genome (SCANG)) for analyzing WGS data that flexibly detects the sizes and the locations of rare-variants association regions without the need of specifying a prior fixed window size. The proposed method controls the genome-wise type I error rate and accounts for the linkage disequilibrium among genetic variants. It allows the detected rare variants association region sizes to vary across the genome. Through extensive simulated studies that consider a wide variety of scenarios, we show that SCANG substantially outperforms several alternative rare-variant association detection methods while controlling for the genome-wise type I error rates. We illustrate SCANG by analyzing the WGS lipids data from the Atherosclerosis Risk in Communities (ARIC) study.

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ScanSAT: Unlocking Static and Dynamic Scan Obfuscation

IEEE Transactions on Emerging Topics in Computing ◽

10.1109/tetc.2019.2940750 ◽

2019 ◽

pp. 1-1 ◽

Cited By ~ 3

Author(s):

Lilas Alrahis ◽

Muhammad Yasin ◽

Nimisha Limaye ◽

Hani Saleh ◽

Baker Mohammad ◽

...

Keyword(s):

Dynamic Scan

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Cerebral perfusion, vascular spasm, and outcome in patients with ruptured intracranial aneurysms

Journal of Neurosurgery ◽

10.3171/jns.1977.47.1.0044 ◽

1977 ◽

Vol 47 (1) ◽

pp. 44-49 ◽

Cited By ~ 41

Author(s):

Patrick J. Kelly ◽

Ralph J. Gorten ◽

Robert G. Grossman ◽

Howard M. Eisenberg

Keyword(s):

Patient Outcome ◽

Cerebral Perfusion ◽

Intracranial Aneurysms ◽

Perfusion Scintigraphy ◽

Content Type ◽

Intracranial Surgery ◽

Dynamic Scan ◽

Vascular Spasm ◽

Ruptured Intracranial Aneurysms ◽

Fine Print

✓ In a retrospective study of 44 patients with verified ruptured intracranial aneurysms, the results of radionuclide cerebral perfusion scintigraphy (dynamic brain scanning) and the presence or absence of arteriographic spasm were correlated with the clinical outcome. The data indicated that patients with normal dynamic scans had a better outcome as a group and following intracranial surgery than those in whom perfusion was reduced. Patients with normal perfusion had a higher incidence of preoperative rebleeding from their aneurysms, while patients with reduced perfusion had a higher incidence of infarction, especially after intracranial surgery. There was no correlation between the presence or absence of arteriographic spasm and the results of the dynamic scans, and no correlation between the presence or absence of spasm and the outcome of the group as a whole. However, in some individual cases with severe spasm, reduced perfusion on the dynamic scan and a poor outcome were noted. It was concluded that the results of the dynamic scan correlated better with eventual patient outcome than the presence or absence of arteriographic spasm. It is therefore suggested that patients in Grades I and II with normal dynamic scans be operated on promptly to prevent rebleeding, and that surgery in patients in Grades I and II with abnormal dynamic scans be delayed until the dynamic scan returns to normal.

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