Abstract | PURPOSE: To evaluate the effect of increasing the sampling interval from 1 second (1 image per second) to 2 seconds (1 image every 2 seconds) on computed tomographic (CT) perfusion ( CTP) of head and neck tumors. MATERIALS AND METHODS: Twenty patients underwent CTP studies of head and neck tumors with images acquired in cine mode for 50 seconds using sampling interval of 1 second. Using deconvolution-based software, analysis of CTP was done with sampling interval of 1 second and then 2 seconds. Perfusion maps representing blood flow, blood volume, mean transit time, and permeability surface area product (PS) were obtained. Quantitative tumor CTP values were compared between the 2 sampling intervals. Two blinded radiologists compared the subjective quality of CTP maps using a 3-point scale between the 2 sampling intervals. Radiation dose parameters were recorded for the 2 sampling interval rates. RESULTS: No significant differences were observed between the means of the 4 perfusion parameters generated using both sampling intervals; all P >0.05. The 95% limits of agreement between the 2 sampling intervals were -65.9 to 48.1) mL/min per 100 g for blood flow, -3.6 to 3.1 mL/100 g for blood volume, -2.9 to 3.8 seconds for mean transit time, and -10.0 to 12.5 mL/min per 100 g for PS. There was no significant difference between the subjective quality scores of CTP maps obtained using the 2 sampling intervals; all P > 0.05. Radiation dose was halved when sampling interval increased from 1 to 2 seconds. CONCLUSIONS: Increasing the sampling interval rate to 1 image every 2 seconds does not compromise the image quality and has no significant effect on quantitative perfusion parameters of head and neck tumors. The radiation dose is halved.
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Authors | Ahmed M Tawfik, Ahmed A Razek, Galal Elhawary, Nihal M Batouty |
Journal | Journal of computer assisted tomography
(J Comput Assist Tomogr)
2014 May-Jun
Vol. 38
Issue 3
Pg. 469-73
ISSN: 1532-3145 [Electronic] United States |
PMID | 24651742
(Publication Type: Journal Article)
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Topics |
- Head and Neck Neoplasms
(diagnostic imaging)
- Humans
- Perfusion Imaging
(methods)
- Radiation Dosage
- Radiation Protection
(methods)
- Radiographic Image Interpretation, Computer-Assisted
(methods)
- Reproducibility of Results
- Sample Size
- Sensitivity and Specificity
- Tomography, X-Ray Computed
(methods)
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