The aim of this study was to find an optimal optimization skin flash thickness in volumetric modulated arc radiotherapy of the breast in consideration of soft tissue deformations during the treatment course. Ten breast radiotherapy patients with axillary lymph node inclusion were retrospectively planned with volumetric modulated arc radiotherapy technique. The plans were optimized with the planning target volume (PTV) extending outside the skin contour by 0, 5, 7, and 10 mm; and with optimization boluses of 3 or 5 mm on the extended PTV. The final dose was calculated without the bolus. The plans were compared in terms of PTV homogeneity and conformity, and dose minima and maxima. The doses to organs at risk were also evaluated. The doses were recalculated in real patient geometries based on cone beam computed tomography (CBCT) images captured 3 to 6 times during each patient's treatment course. The optimization to the PTV without the PTV extension resulted in the best CTV coverage in the original plans (V95% = 98.0% ± 1.2%). However, when these plans were studied in real CBCT-based patient geometries, the CTV V95% was compromised (94.6% ± 8.3%). In addition, for the surface (4 mm slap inside the PTV 4 mm below the body contour) dose V95% was reduced from the planned 74.7% ± 7.5% to the recalculated 65.5% ± 11.5%. Optimization with an 8-mm bolus to a PTV with 5-mm extension was the most robust choice to ensure the CTV and surface dose coverage (recalculated V95% was 95.2% ± 6.4% and 74.6% ± 8.4%, respectively). In cases with the largest observed deformations, even a 10-mm PTV extension did not suffice to cover the target. Optimization with a 5-mm PTV extension and an 8-mm optimization bolus improved the surface dose and slightly improved the CTV dose when compared to no extension plans. For deformations over 1 cm, no benefit was seen in PTV extensions and replanning is recommended. Frequent tangential and CBCT imaging should be used during treatment course to detect potential large anatomical changes. 相似文献
ABSTRACTObjective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group. Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared. Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group. Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients. 相似文献
Beauty has many facets, and research shows that there are many biologic, psychologic, cultural, and social aspects that influence how beauty and attractiveness are perceived. Beauty preferences are, in part, an effect of a rudimentary cognitive process that appears quite early in life, with humans having a seemingly automatic ability to categorize a person as beautiful or not. This instantaneous capability of human beauty categorization is partially determined by a function of physical features, such as facial averageness, symmetry, and skin homogeneity. For decades, the mass media platform has introduced certain criteria to what establishes beauty, and more recently, social media, instant photo sharing, and editing apps have further influenced how society adapts to beauty principles. 相似文献
Comparison with control groups of untreated patients suggests that right-breast-cancer patients who receive radiotherapy have a higher rate of heart disease. Dose constraint for heart has been established to minimize radiotherapy-induced cardiotoxicity during left breast cancer treatment. Additionally, it is suggested to minimize the dosage on left anterior descending (LAD) artery. Right coronary artery (RCA), is the second largest artery, after left main coronary artery, supplying the heart. A dose evaluation study is not present for RCA; the proximal part of which is included in the irradiation field during breast cancer treatment of right breast. To investigate the presence of a correlation, doses resulting from right and left breast radiotherapy on proximal RCA (pRCA), LAD, and heart are evaluated in this study. Forty breast cancer patients who went under breast-conserving surgery are the subject of this study. Four groups were established; right breast, right breast and internal mammary (IM), left breast and left breast, and IM. pRCA, LAD, and heart volumes were contoured for each group on the planning tomographies. Resultant doses of tangential fields planning on these volumes were compared using dose-volume histograms. Mean and maximum doses of pRCA were statistically compared between groups. The highest mean and maximum point doses (192 to 284 cGy) were found in the right breast + IM group (p < 0.05). The mean and maximum doses only in the right breast and left breast + IM group did not differ statistically. However, the mean and maximum pRCA doses in these 2 groups were higher than only the left breast group (p < 0.05). pRCA receives high doses during radiotherapy of right and left breast especially if IM is included. This may predispose to coronary artery disease. 相似文献
Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild... 相似文献
Purpose: To use polymerase chain reaction (PCR) and Goldmann-Witmer coefficient (GWC) calculation to diagnose infectious uveitis.
Methods: Prospective cross-sectional study.
Results: Twenty-seven of 106 patients had positive PCR and/or GWC results on aqueous humor (AH) sampling and 15 of 27 (55.6%) were HIV-positive. Patients with non-anterior uveitis (NAU) were more likely to be HIV+ (p = 0.005). More than 1 possible pathogen was identified in 9 of 27 patients of whom 7 were HIV+. The final clinical diagnosis was discordant with AH findings in 9 of 27 cases. A positive EBV PCR result was associated with a discordant diagnosis (p = 0.001). All cases of herpetic anterior uveitis (42.9% HIV+) tested PCR-/GWC+ while all cases of herpetic NAU tested PCR+/GWC- (83.3% HIV+). All rubella virus cases were PCR+/GWC+.
Conclusion: PCR is useful to diagnose herpetic NAU in HIV+ patients while GWC is useful to diagnose herpetic anterior uveitis. 相似文献