Purpose: To evaluate the image quality and the radiation dose of 3D-computed tomography angiography (3D-CTA) with a high-pitch protocol and a hybrid iterative reconstruction (HIR).
Materials And Methods: This was a prospective study and thirty patients were scanned at a 0.51-helical pitch with filtered back-projection (FBP, protocol-A), and 30 patients were scanned at a 0.91-helical pitch with FBP and HIR (protocol-B and C). The mean volume CT dose index (CTDI(vol)), image noise, and mean cerebral arterial and venous attenuation were compared between the three protocols. Two readers assessed image noise, arterial contrast and venous overlap.
Results: The mean CTDI(vol) of protocol-B/C (38.9 mGy) was lower than that of protocol-A (49.7 mGy). Mean image noise of protocol-B [12.6 ± 1.3 Hounsfield units (HU)] was higher than that of protocol-A (10.3 ± 1.2 HU). There was no significant difference in arterial attenuation between protocol-A (327.5 ± 57.5 HU) and C (327.7 ± 59.4 HU). Venous attenuation of protocol-C (148.5 ± 50.4 HU) was lower than that of protocol-A (185.9 ± 50.6 HU). In qualitative analysis, the image noise of protocol-B was higher than that of protocol-A/C. Venous enhancement of protocol-B/C was more inconspicuous than that of protocol-A.
Conclusions: 3D-CTA with a high-pitch protocol and HIR can reduce radiation dose while decreasing venous enhancement and image noise to an adequate level for diagnosis.
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http://dx.doi.org/10.1007/s11604-015-0477-3 | DOI Listing |
Med Phys
January 2025
National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
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January 2025
Department of Physics "A. Pontremoli", University of Milan & INFN sez. Milano, Milano, Italy. Electronic address:
Purpose: This work aims at investigating, via in-silico evaluations, the noise properties of an innovative scanning geometry in cone-beam CT (CBCT): eCT. This scanning geometry substitutes each of the projections in CBCT with a series of collimated projections acquired over an oscillating scanning trajectory. The analysis focused on the impact of the number of the projections per period (PP) on the noise characteristics.
View Article and Find Full Text PDFSci Rep
January 2025
Hannover Centre for Optical Technologies (HOT), Leibniz University Hannover, Hannover, Germany.
Hyperspectral imaging (HSI) systems acquire images with spectral information over a wide range of wavelengths but are often affected by chromatic and other optical aberrations that degrade image quality. Deconvolution algorithms can improve the spatial resolution of HSI systems, yet retrieving the point spread function (PSF) is a crucial and challenging step. To address this challenge, we have developed a method for PSF estimation in HSI systems based on computed wavefronts.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Electronics, Information and Communication Engineering, Kangwon National University, Samcheok, Republic of Korea.
Detecting brain tumours (BT) early improves treatment possibilities and increases patient survival rates. Magnetic resonance imaging (MRI) scanning offers more comprehensive information, such as better contrast and clarity, than any alternative scanning process. Manually separating BTs from several MRI images gathered in medical practice for cancer analysis is challenging and time-consuming.
View Article and Find Full Text PDFSci Rep
January 2025
College of Computer Sciences, Anhui University, Hefei, 230039, China.
Decoding the semantic categories of complex sceneries is fundamental to numerous artificial intelligence (AI) infrastructures. This work presents an advanced selection of multi-channel perceptual visual features for recognizing scenic images with elaborate spatial structures, focusing on developing a deep hierarchical model dedicated to learning human gaze behavior. Utilizing the BING objectness measure, we efficiently localize objects or their details across varying scales within scenes.
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