Comparison of dosimetric parameters derived from whole organ and wall contours for bladder and rectum in cervical cancer patients treated with intracavitary and interstitial brachytherapy

Publication date: Available online 6 February 2018
Source:Radiotherapy and Oncology
Author(s): Rachel Gerber, Alexandra Rink, Jennifer Croke, Jette Borg, Akbar Beiki-Ardakani, Anthony Fyles, Michael Milosevic, Jason Xie, Harald Keller, Kathy Han
For volumes up to 2 cm³ of the bladder and possibly up to 5 cm³ of the rectum, doses computed from the whole organ were good estimates of the doses in the wall in cervix brachytherapy, and there were no significant differences between patients treated with or without interstitial needles.



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Clinical implementation of contrast-enhanced four-dimensional dual-energy computed tomography for target delineation of pancreatic cancer

Publication date: Available online 6 February 2018
Source:Radiotherapy and Oncology
Author(s): Shingo Ohira, Kentaro Wada, Takero Hirata, Naoyuki Kanayama, Toshiki Ikawa, Tsukasa Karino, Yuya Nitta, Masaru Isono, Yoshihiro Ueda, Masayoshi Miyazaki, Masahiko Koizumi, Teruki Teshima
Background and purposeThe accurate delineation of pancreatic tumor with respiratory motion is challenging. This study demonstrates the application of contrast-enhanced four-dimensional dual-energy computed tomography (CE-4D-DECT) for tumor delineation and assesses the objective and subjective image quality.Material and methodsTwelve patients underwent CE-4D-DECT, and quantitative spectral analysis was performed on the resulting virtual monochromatic images (VMI) to determine the optimal VMI (O-VMI) with the highest contrast-to-noise ratio (CNR). The objective value of the CNR between pancreatic parenchyma and tumor, and the subjective measurement with five-point scale were compared between O-VMI, standard VMI (S-VMI, 77 keV) and single energy CT (SECT, 120 kVp).ResultsThe CNR was the highest in the VMI at 60 keV, and the corresponding CNR in the O-VMI (3.4) was significantly higher (p < 0.05) than that in the S-VMI (2.4) and the SECT (2.7). The overall mean subjective measurements among 4 radiation oncologists were higher for the O-VMI over the S-VMI and SECT with respect to overall image quality (4.0, 3.3 and 3.7, respectively), tumor enhancement (3.4, 2.6 and 3.2, respectively), and vessel delineation (4.2, 3.6 and 4.2, respectively).ConclusionsThe O-VMI derived from the CE-4D-DECT demonstrated its superiority over the S-VMI and SECT in depicting pancreatic tumor.



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Intraosseous venous structures adjacent to the jugular tubercle associated with an anterior condylar dural arteriovenous fistula

Abstract

Purpose

Although involvement of the osseous component with an anterior condylar dural arteriovenous fistula (AC-DAVF) has been frequently described, osseous venous structures in which AC-DAVFs develop have not been fully elucidated. We investigated osseous venous structures adjacent to the hypoglossal canal in normal controls and patients with AC-DAVFs.

Methods

The study included 50 individuals with unruptured aneurysms as normal controls and seven patients with AC-DAVFs. Osseous venous structures adjacent to the hypoglossal canal in normal controls were analyzed using computed tomography (CT) digital subtraction venography. In patients with AC-DAVFs, the fistulous pouches, draining veins, and surrounding venous structures were examined using cone beam CT.

Results

In 46.0% of laterals in normal controls, osseous venous structures were visualized within the jugular tubercle superomedially to the hypoglossal canal. We named these structures the jugular tubercle venous complex (JTVC). The JTVC was always continuous with the anterior condylar vein and was sometimes connected to surrounding venous channels. We detected nine fistulous pouches in the seven patients with AC-DAVFs. The fistulous pouches were in the JTVC (33.3%), anterior condylar vein (33.3%), and other venous channels within the exoccipital region (33.3%).

Conclusion

Although the JTVC is a venous structure frequently found in normal people, it had not been investigated until now. The venous channel between the anterior condylar vein and JTVC is a common origin site for AC-DAVFs, and it was associated with 66.6% of the AC-DAVF cases in the current study.

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Editorial Board

Publication date: March 2018
Source:Journal of Environmental Radioactivity, Volume 183





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Sequential analyses of actinides in large-size soil and sediment samples with total sample dissolution

Publication date: Available online 6 February 2018
Source:Journal of Environmental Radioactivity
Author(s): Maoyi Luo, Shan Xing, Yonggang Yang, Lijuan Song, Yan Ma, Yadong Wang, Xiongxin Dai, Steffen Happel
There is a growing demand for the determination of actinides in soil and sediment samples for environmental monitoring and tracing, radiological protection, and nuclear forensic reasons. A total sample dissolution method based on lithium metaborate fusion, followed by sequential column chromatography separation, was developed for simultaneous determination of Pu, Am and Cm isotopes in large-size environmental samples by alpha spectrometry and mass spectrometric techniques. The overall recoveries of both Pu and Am for the entire procedure were higher than 70% for large-size soil samples. The method was validated using 20 g of soil samples spiked with known amounts of ²³⁹Pu and ²⁴¹Am as well as the certified reference materials IAEA-384 (Fangataufa Lagoon sediment) and IAEA-385 (Irish Sea sediment). All the measured results agreed very well with the expected values.



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Comparison of dosimetric parameters derived from whole organ and wall contours for bladder and rectum in cervical cancer patients treated with intracavitary and interstitial brachytherapy

For volumes up to 2 cm3 of the bladder and possibly up to 5 cm3 of the rectum, doses computed from the whole organ were good estimates of the doses in the wall in cervix brachytherapy, and there were no significant differences between patients treated with or without interstitial needles.

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Traffic University: How Small Changes in Lifestyle Can Change Your Life

Publication date: March–April 2018
Source:Current Problems in Diagnostic Radiology, Volume 47, Issue 2
Author(s): Puneet Bhargava




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