Accuracy of Intracavitary Applicator Reconstruction for Cervix Cancer Brachytherapy

The accuracy of intracavitary applicator reconstruction for cervical cancer was assessed. A homemade phantom that mimics clinical applicator placement and reference points was used. Three stainless steel (15°, 30°, and 45°) tandems, x-ray markers, and three reference points were used to compare radiography- and CT-based systems. For CT reconstructions, two Fletcher CT compatible (15° and 30°) tandems, two ovoids, and two reference points, with and without inserted x-ray markers, were used. A 2.5-mm CT slice thickness was used. To check for inter- and intra-operator variations in CT, only a 30° tandem without x-ray markers and 1.25-mm CT slice thickness were used. Applicators were reconstructed three times for each image set to verify the operator reproducibility. A 6 Gy dose was prescribed and normalized at AL-point. Source dwell times were compared to check for dose variation at A-point. Maximum standard deviations SD (σ) for radiography and CT reconstructions were 0.35 and 0.83mm, respectively. Analysis of variance for the means of 15° and 30° tandems showed no significant difference. Levene’s test proved insignificant difference for 15° tandem (p value = 0.131), whereas it showed a significant difference for 30° tandem (p value = 0.011). This phantom study showed that the variance of dwell times between the two methods for 30° tandem was statistically significant due to increased applicator curvature. CT proves superiority to radiography. X-ray marker method was more accurate but has less image quality. Inter- and intra-oncologist variations showed good agreement

Thoracic manifestations of adult T-cell leukemia/lymphoma on chest CT: difference between clinical subtypes

PURPOSE:We aimed to evaluate thoracic computed tomography (CT) findings in adult T-cell leukemia/lymphoma (ATL) and their differences among clinical subtypes.METHODS:Thoracic CT scans of 49 ATL patients were retrospectively reviewed. On CT scans, the presence of lung parenchymal abnormalities (10 patterns), enlarged lymph nodes, pleural and pericardial effusions, and subcutaneous nodules was evaluated by two radiologists in cooperation. According to the Shimoyama criteria, the patients were divided into aggressive ATL group (n=28, acute and lymphoma types) and indolent ATL group (n=21, chronic and smoldering types). Differences in the prevalence of the CT findings between the two groups were examined. In the indolent ATL group, CT scans of 10 patients who eventually underwent transformation to aggressive ATL were also evaluated.RESULTS:In aggressive ATL, enlarged lymph nodes (68%) was the most frequently observed finding. Several patterns of lung abnormalities were observed, such as ground-glass attenuation (36%), bronchial wall thickening (32%), nodules (29%), and centrilobular opacities (29%). In indolent ATL, enlarged lymph nodules (24%) and bronchiectasis (24%) were relatively frequently detected. Overall, the incidence of abnormal findings was higher in aggressive than in indolent ATL, except for bronchiectasis. Patients with transformation to aggressive ATL frequently demonstrated enlarged lymph nodes (80%).CONCLUSION:On thoracic CT, enlarged lymph nodes and various lung and airway abnormalities, such as ground-glass attenuation and bronchial wall thickening, were observed in ATL patients, particularly those with aggressive ATL. Bronchiectasis was similarly found in patients with indolent ATL and aggressive ATL

Symptomatic jugular venous reflux with dilatation of the superior ophthalmic vein mimicking cavernous dural arteriovenous fistula

We report a case of symptomatic jugular venous reflux (JVR) with dilatation of left superior ophthalmic vein (SOV), mimicking cavernous dural arteriovenous fistula (AVF). Severe JVR was caused by an AVFfor hemodialysis access and the narrowing of the left brachiocephalic vein. In-flow signals were found from the left internal jugular vein to left SOV on magnetic resonance angiography, and T1-weighted image and T2-weighted images demonstrated flow voids in bilateral sigmoid sinuses and confluence of sinuses due to rapid retrograde venous flow. We would like to emphasize that the presence of in-flow signals/flow voids in the venous sinuses may be the key imaging clues to distinguish JVR with dilatation of the SOV from cDAVF

Computed tomography examinations of the surface and internal morphologies of the upper face in Ryukyu Islanders and mainland Japanese population

Using computed tomography, we examined the surface and internal morphologies of the upper face of people living on the Ryukyu Islands and mainland Japanese, focusing on the nasal root protrusion and eyeball position. The results showed that the nasal root protrusion on the surface was influenced by a combination of changes in both hard and soft tissues, such as skeletal nasal protrusion, eyeball recession, and skin thickness. The eyeball position became more posterior as the orbital cavity height and depth increased. Compared with people originating from mainland Japan, Ryukyu Islanders had a more prominent nasal root at both surface and skeletal levels, and a lower orbital rim relative to its internal height. However, a significant difference in the eyeball position and skin thickness was not detected. Therefore, the skeletal nasal root protrusion, not soft tissue configuration, is likely to account for the difference in the surface nasal root protrusion between the two populations. These findings will contribute to a better understanding of the association between hard and soft tissue configurations and the diversification of human facial features at the individual and population levels

Advanced CT images reveal nonmetric cranial variations in living humans

Two mainland Japanese males were examined with a computer tomography (CT) X-ray scanner to reconstruct three-dimensional CT simulation images of their cranial anatomy and to check for the presence/absence of 23 nonmetric cranial traits. Surface anatomy for scoring 19 nonmetric cranial variations was clearly observed among the 23 variations. Evaluation of the four other traits might have been disturbed due to dental treatment history, small variations in the images, or X-ray radiation condition. However, these disturbances could be overcome by a combination of simple thin-sliced CT images and magnetic resonance imaging. We have thus developed a new anatomical field for elucidating human morphology

Reproducibility of pulmonary blood flow measurements by phase-contrast MRI using different 1.5 T MR scanners at two institutions

Background Magnetic resonance imaging (MRI) can be beneficial for diagnosis of disease by offering quantitative information. However, reproducibility can be a major problem when there is a numerical threshold in multi-institution, multi-vendor situations. Purpose To measure pulmonary blood flow with phase-contrast (PC) imaging using two different MR scanners (1.5 T) at different institutions in the same participants and to examine the reproducibility of the measurements. Material and Methods Participants were 10 healthy volunteers (5 men; age range, 27–36 years). The measurements included the mean and maximal blood velocities, the mean blood flow volume, and the acceleration time and volume (AT and AV), derived from the time-flow curve of the PC-MRI. Simultaneously obtained maximal, minimal, and mean areas from regions of interest set in the pulmonary artery were also calculated. In order to calculate the reproducibility of the quantitative variables, intra-class correlation coefficients (ICCs) were employed. When an adequate ICC was obtained, Bland–Altman analysis was conducted to identify any systematic bias. Results The ICCs were almost perfect for the mean blood flow volume and the AV (r = 0.82 and 0.80), and were substantial in the mean and maximal areas, and the AT (r = 0.63, 0.74, and 0.64, respectively). However, there was a fixed bias in the area measurement between the two scanners. Also, the AV had a proportional bias. Conclusion Our results reveal that various indices derived from PC-MRI on different MR scanners are promising as common indices for pulmonary flow assessment. Research and clinical use of PC-MRI for the pulmonary artery is expected to extend to multi-institution situations