bluuebunny/crossref_metadata_2025_split huggingface dataset:
SU‐E‐T‐484: A New Method of Aligning Patient Setup Lasers in Radiation Therapy
Authors: Hwang U , Lim Y , Choi S , Kwak J , Yoon K , Cho K , Jeong C , Kim M , Jeong J , Park J , Shin D , Lee S , Kim J , Park S , Kim S 
Published: July 2014

Purpose:To develop a new method to align the patient setup lasers in radiation therapy and examine its validity and effectiveness.Methods:The new laser alignment method was realized by a device composed of both a metallic base plate and few acrylic transparent plates with a cross hair line on each of them. The holders of radiochromic films were prepared in the device to find a radiation isocenter. The right laser positions could be found optically by matching the shadows of all the cross hairs in the gantry head and the device. The repeatability and reproducibility (R&R) of laser alignments and the dependency of the alignment on the position error of the light source were evaluated by comparing the standard deviations and the means of the measured laser positions. After aligning the lasers optically, a radiation isocenter was found by a collimator spoke shot and the gantry spoke shot, and then the lasers were parallely translated to the isocenter.Results:In the R&R test, the standard deviation was 1.14 mm for the new method whereas it was 1.49 mm or 2.76 mm for the conventional method with either high‐ or low‐precision levels. In the test of the dependency on the position error of the light source, the mean laser position was shifted by 5.3 mm corresponding to the shift of the light source, 4.8 mm for the new method, but for the conventional method the laser position was shifted more than 7 times than that. The positional shift could be corrected by a parallel translation to the isocenter in the new method.Conclusion:A new laser alignment method was devised for radiation therapy and tested successfully. The method enabled us to align the lasers easily and accurately without repetition, and all lasers could be finally aligned to the radiation isocenter.
SU‐E‐T‐498: Energy Minimization and Dose‐Volume Inverse Optimization in Prostate Cancer
Authors: Mihaylov I , Moros E 
Published: July 2014

Purpose:To compare dose‐volume (DVH) and energy minimization‐based (EM) optimization for prostate cancer cases.Methods:A dozen of prostate plans were retrospectively studied. For each case two IMRT plans were generated, one with DVH and the other with EM objective cost function. Those different objective functions were used only for the organs at risk (OARs), while target objectives were achieved through DVH cost functions. The plans used the same beam angles, maximum number of segments per plan, minimum segment area and MUs per segment. Both plans were normalized such that 95% of the PTV was covered by the same prescription dose. After prescription was achieved, doses to the OARs were iteratively lowered until the standard deviation of the dose across the PTV was ~3.5%. Plan quality was evaluated by several dose indices (DIs). A DI represents the dose delivered to certain volume of a structure. Tallied DIs were for rectum and bladder 10%, 40%, 60% volumes, and 1% volumes of the femoral heads as surrogate for maximum doses. Statistical significance in the differences among DIs was quantified with two‐tailed paired t‐tests.Results:On average EM plans performed better than DVH plans. Statistically significant dose reduction in rectum DI10, DI40, and DI60, were 2.6%, 25.7%, and 35.9%, respectively. For bladder DI10, DI40, and DI60 the differences were 1.1%, 20.8%, and 29.7%. Left and right femoral head DI1s were better by 33.8% and 27.8% in EM plans. The quoted dose reduction is with respect to EM absolute doses for the DIs.Conclusion:The performance of EM optimization with respect to DVH optimization is patient and DI dependent. While in some cases specific DIs were better with DVH optimization, on average the energy minimization allows better (ranging from 1% to ~40%) OAR sparing than DVH optimization.NIH‐NCI
SU‐E‐T‐501: Normal Tissue Toxicities of Pulsed Low Dose Rate Radiotherapy and Conventional Radiotherapy: An in Vivo Total Body Irradiation Study
Authors: Cvetkovic D , Zhang P , Wang B , Chen L , Ma C 
Published: July 2014

Purpose:Pulsed low dose rate radiotherapy (PLDR) is a re‐irradiation technique for therapy of recurrent cancers. We have previously shown a significant difference in the weight and survival time between the mice treated with conventional radiotherapy (CRT) and PLDR using total body irradiation (TBI). The purpose of this study was to investigate the in vivo effects of PLDR on normal mouse tissues.Materials andMethods:Twenty two male BALB/c nude mice, 4 months of age, were randomly assigned into a PLDR group (n=10), a CRT group (n=10), and a non‐irradiated control group (n=2). The Siemens Artiste accelerator with 6 MV photon beams was used. The mice received a total of 18Gy in 3 fractions with a 20day interval. The CRT group received the 6Gy dose continuously at a dose rate of 300 MU/min. The PLDR group was irradiated with 0.2Gyx20 pulses with a 3min interval between the pulses. The mice were weighed thrice weekly and sacrificed 2 weeks after the last treatment. Brain, heart, lung, liver, spleen, gastrointestinal, urinary and reproductive organs, and sternal bone marrow were removed, formalin‐fixed, paraffin‐embedded and stained with H&E. Morphological changes were observed under a microscope.Results:Histopathological examination revealed atrophy in several irradiated organs. The degree of atrophy was mild to moderate in the PLDR group, but severe in the CRT group. The most pronounced morphological abnormalities were in the immune and hematopoietic systems, namely spleen and bone marrow. Brain hemorrhage was seen in the CRT group, but not in the PLDR group.Conclusions:Our results showed that PLDR induced less toxicity in the normal mouse tissues than conventional radiotherapy for the same dose and regimen. Considering that PLDR produces equivalent tumor control as conventional radiotherapy, it would be a good modality for treatment of recurrent cancers.
SU‐E‐T‐513: Probabilistic Approach to Plan Evaluation in Linac‐Based Stereotactic Radiosurgery: A Patient Specific Uncertainty Analysis
Authors: Park P , Roper J , Fox T , Schreibmann E , Elder E , Tejani M , Curran W , Crocker I , Dhabaan A 
Published: July 2014

Purpose:Acoustic neuroma is treated using highly conformal, framed‐based radiosurgery. The gross target volume (GTV) is located near the radiosensitive brainstem. Currently, plan evaluation methods that consider GTV dose conformity and dose to organs at risk (OAR) do not account for setup uncertainty, thereby potentially giving a false sense of target coverage and OAR sparing. More realistic plan evaluations should consider delivery uncertainties. In this work, we introduce a new plan evaluation method based on probability and investigate the effect of translational and rotational setup errors.Methods:Clinically approved 18 acoustic neuroma treatment plans were studied retrospectively. For each treatment plan, 200 new dose distributions were re‐calculated while introducing both translational (in all cardinal directions) and rotational errors (in all 3 orthogonal rotation angles). The magnitude of errors for each simulation was randomly generated from the Gaussian distribution with one standard deviation of 0.5 mm and 0.5 degree respectively. From the simulated dose distributions, an approximated probability density function of dose objective for both GTV and brainstem were calculated. The probability density function was then used to compute the probability of delivering prescribed dose to 90% of GTV for each patient. For brainstem, the probability of limiting maximum dose to 11Gy was calculated. These probabilistic metrics were then analyzed with respect to GTV volume, conformity index, and min and max dose to the GTV and brainstem.Results:Across all cases, the average probability of delivering prescribed dose to the 90% of GTV volume was 85±14%. Four patients showed > 50% risk of exceeding 11Gy limit to the brainstem.Conclusion:In highly conformal, single fraction radiosurgery, a small setup error can be critical. We found that the probabilistic assessment of plan objectives can be used to quantitatively assess true target coverage better than the conventional plan assessment metrics.
SU‐E‐T‐521: Feasibility Study of a Rotational Step‐And‐Shoot IMRT Treatment Planning Approach
Authors: Zhu X , Chang S , Cullip T , Yuan L , Lian J , Zhang X , Tang X , Tracton G , Dooley J 
Published: July 2014

Purpose:Rotational step‐and‐shot IMRT (r‐IMRT) could improve delivery efficiency with good dose conformity, especially if it can leverage the burst mode of the accelerator where radiation is turned on/off momentarily while the gantry rotates continuously. The challenge for the r‐IMRT planning is to minimize the number of beams to achieve a fast and smooth rotational delivery.Methods:Treatment plans for r‐IMRT were created using an in‐house treatment planning system. To generate the plan using a very few beams, gantry angle was optimized by weighting the beam monitoring unit (MU), and beam shape optimization was a combination of column search with k‐means clustering. A prostate case and a head and neck case were planned using r‐IMRT. The dosimetry is compared to s‐IMRT planned with Varian Eclipse treatment planning system.Results:With the same PTV dose coverage D95=100%, the r‐IMRT plans shows comparable sparing as the s‐IMRT plans in the prostate for the rectum D10cc and the bladder Dmean, and in the head and neck for the spinal cord Dmax, the brain stem Dmax, the left/right parotid Dmean, the larynx Dmean, and the mandible Dmean. Both plans meet the established institutional clinical dosimetric criteria. The r‐IMRT plan uses 19 beam/405 MU for the prostate, and 68 beam/880 MU for the head and neck, while the s‐IMRT uses 7 beam/724 MU and 9 beam/1812 MU, respectively. Compared to the corresponding s‐IMRT, r‐IMRT has a reduction of MUs of 44% for the prostate case and 41% for the head and neck case.Conclusions:We have demonstrated the feasibility of a rotational step & shoot IMRT treatment planning approach that significantly shortens the conventional IMRT treatment beam‐on time without degrading the dose comformity.
SU‐E‐T‐528: Robustness Evaluation for Fiducial‐Based Accelerated Partial Breast Proton Therapy
Authors: Zhao L , Rana S , Zheng Y 
Published: July 2014

Purpose:To investigate the robustness of the proton treatment plans in the presence of rotational setup error when patient is aligned with implanted fiducials.Methods:Five Stage I invasive breast cancer patients treated with the APBP protocol (PCG BRE007‐12) were studied. The rotational setup errors were simulated by rotating the original CT images around the body center clockwise and counterclockwise 5 degrees (5CW and 5CCW). Manual translational registration was then performed to match the implanted fiducials on the rotated images to the original dataset. Patient contours were copied to the newly created CT set. The original treatment plan was applied to the new CT dataset with the beam isocenter placed at the geometrical center of PTV. The dose distribution was recalculated for dosimetric parameters comparison.Results:CTV and PTV (D95 and V95) coverages were not significantly different between the two simulated plans (5CW and 5CCW) and the original plan. PTV D95 and CTV D95 absolute difference among the three plans were relatively small, with maximum changes of 0.28 CGE and 0.15 CGE, respectively. PTV V95 and CTV V95 absolute differences were 0.79% and 0.48%. The dosage to the thyroid, heart, contralateral breast and lung remained zero for all three plans. The Dmax and Dmean to the volume of ipsilateral breast excluding CTV were compared, with maximum difference values of 1.02 CGE for Dmax and 3.56 CGE for Dmean. Ipsilateral lung Dmean maintained no significant changes through the three plan comparison, with the largest value 0.32 CGE. Ipsilateral lung Dmax was the most sensitive parameter to this simulation study, with a maximum difference at 20.2 CGE.Conclusion:Our study suggests that fiducial‐based Accelerated Partial Breast Proton Therapy is robust with respect to +/− 5 degree patient setup rotational errors, as long as the internal fiducial markers are used for patient alignment.
High-Protein, Low-Fat, Short-Term Diet Results in Less Stress and Fatigue Than Moderate-Protein, Moderate-Fat Diet During Weight Loss in Male Weightlifters: A Pilot Study
Authors: Helms Eric R. , Zinn Caryn , Rowlands David S. , Naidoo Ruth , Cronin John 
Published: July 2014

Purpose:Athletes risk performance and muscle loss when dieting. Strategies to prevent losses are unclear. This study examined the effects of two diets on anthropometrics, strength, and stress in athletes.Methods:This double-blind crossover pilot study began with 14 resistance-trained males (20-43 yr) and incurred one dropout. Participants followed carbohydrate-matched, high-protein low-fat (HPLF) or moderate-protein moderate-fat (MPMF) diets of 60% habitual calories for 2 weeks. Protein intakes were 2.8g/kg and 1.6g/kg and mean fat intakes were 15.4% and 36.5% of calories, respectively. Isometric midthigh pull (IMTP) and anthropometrics were measured at baseline and completion. The Daily Analysis of Life Demands of Athletes (DALdA) and Profile of Mood States (POMS) were completed daily. Outcomes were presented statistically as probability of clinical benefit, triviality, or harm with effect sizes (ES) and qualitative assessments.Results:Differences of effect between diets on IMTP and anthropometrics were likely or almost certainly trivial, respectively. Worse than normal scores on DALDA part A, part B and the part A “diet” item were likely more harmful (ES 0.32, 0.4 and 0.65, respectively) during MPMF than HPLF. The POMS fatigue score was likely more harmful (ES 0.37) and the POMS total mood disturbance score (TMDS) was possibly more harmful (ES 0.29) during MPMF than HPLF.Conclusions:For the 2 weeks observed, strength and anthropometric differences were minimal while stress, fatigue, and diet-dissatisfaction were higher during MPMF. A HPLF diet during short-term weight loss may be more effective at mitigating mood disturbance, fatigue, diet dissatisfaction, and stress than a MPMF diet.
Preparation and Electrical Properties of Ba2TiOSi2−xGexO7 (x=0.0 and 0.2) Ferroelectric Ceramics
Authors: Barbar S. K. , Roy M. 
Published: July 2014

Polycrystalline ceramic samples of pure and germanium (Ge4+) doped fresnoite of general formula Ba2TiOSi2−xGexO7 (x=0.0 and 0.2) have been prepared by solid state reaction technique. The formation of the single phase compound was confirmed by X-ray diffraction and the structural parameters were refined by the Rietveld refinement technique. The dc conductivity of both the materials has been measured as a function of temperature from room temperature to 753 K and activation energy was calculated using the relation σ = σoexp(-Ea/kt). The activation energy 4.74 eV obtained for the pure compound is very high in comparison with 1.47 eV of Ge4+-substituted compound. The frequency and temperature dependent dielectric behavior of both the compounds have been studied. The real and imaginary parts of the dielectric constant increase with the increase of temperature.
Validity and Reliability of the Munsell Soil Color Charts for Assessing Human Skin Color
Authors: Reeder Anthony I. , Iosua Ella , Gray Andrew R. , Hammond Vanessa A. 
Published: July 2014

Abstract
Background: Skin pigmentation is a key factor for ultraviolet radiation exposure–related cancers and can make a significant contribution to the patterns of other diseases. For surveys, and to appropriately target cancer control activities, valid and reliable measures of skin color are required.
Methods: Validity and reliability of the Munsell Soil Color Charts were investigated for skin color assessment. The unexposed skin color of 280 university students was measured by spectrophotometer to calculate an Individual Typology Angle (ITA) value, and categorized by two independent raters according to the Munsell system (the latter was repeated after a 7-day interval).
Results: Interrater and intrarater reliability for the Munsell charts was found to be acceptable [intraclass correlation coefficients (ICC) of 0.85 and 0.86, respectively]. When ITA values were converted to the six Del Bino skin color categories, weighted κ for agreement between raters, within rater, and between Munsell chip and spectrophotometer were 0.63, 0.60, and 0.61, respectively. A tendency toward overestimation of the extremes of skin pigmentation was evident, particularly for the “brown” and “dark” skin types.
Conclusions: Study findings suggest that the Munsell Soil Color Charts represent a reliable and valid measurement strategy when assessing skin type.
Impact: The Munsell Year 2000 Soil Color Charts may provide a useful instrument for fieldwork contexts. Subsequent classification of individuals into skin cancer risk categories, rather than the use of precise ITA values, may be sufficient for targeting public health messages for skin cancer prevention and other health risks. Cancer Epidemiol Biomarkers Prev; 23(10); 2041–7. ©2014 AACR.
Adherence to Dietary and Lifestyle Recommendations and Prostate Cancer Risk in the Prostate Testing for Cancer and Treatment (ProtecT) Trial
Authors: Er Vanessa , Lane J. Athene , Martin Richard M. , Emmett Pauline , Gilbert Rebecca , Avery Kerry N.L. , Walsh Eleanor , Donovan Jenny L. , Neal David E. , Hamdy Freddie C. , Jeffreys Mona 
Published: July 2014

AbstractBackground: The World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) published eight recommendations for cancer prevention, but they are not targeted at prostate cancer prevention. We investigated whether adherence to the WCRF/AICR recommendations and a prostate cancer dietary index is associated with prostate cancer risk.Methods: We conducted a nested case–control study of 1,806 prostate-specific antigen (PSA)–detected prostate cancer cases and 12,005 controls in the ProtecT trial. We developed a prostate cancer dietary index by incorporating three dietary factors most strongly associated with prostate cancer. Scores were computed to quantify adherence to the WCRF/AICR recommendations and the prostate cancer dietary index separately.Results: The prostate cancer dietary index score was associated with decreased risk of prostate cancer [OR per 1 score increment: 0.91; 95% confidence interval (CI): 0.84–0.99; Ptrend = 0.04] but the WCRF/AICR index score was not (OR: 0.99; 95% CI: 0.94–1.05; Ptrend = 0.71). There was no heterogeneity in association by prostate cancer stage (P = 0.81) or grade (P = 0.61). Greater adherence to recommendations to increase plant foods (OR per 0.25 index score increment: 0.94; 95% CI: 0.89–0.99; Ptrend = 0.02) and tomato products (OR adherence vs. nonadherence: 0.82; 95% CI: 0.70–0.97; P = 0.02) was inversely associated with overall prostate cancer risk.Conclusions: Adherence to the prostate cancer–specific dietary recommendations was associated with decreased risk of prostate cancer. High intake of plant foods and tomato products in particular may help protect against prostate cancer.Impact: Meeting the WCRF/AICR recommendations alone is insufficient for prostate cancer prevention. Additional dietary recommendations should be developed. Cancer Epidemiol Biomarkers Prev; 23(10); 2066–77. ©2014 AACR.
Clinical Experience With a Novel Electromyographic Approach to Preventing Phrenic Nerve Injury During Cryoballoon Ablation in Atrial Fibrillation
Authors: Mondésert Blandine , Andrade Jason G. , Khairy Paul , Guerra Peter G. , Shohoudi Azadeh , Dyrda Katia , Macle Laurent , Rivard Léna , Thibault Bernard , Talajic Mario , Roy Denis , Dubuc Marc 
Published: July 2014

Background—
Phrenic nerve palsy remains the most frequent complication associated with cryoballoon-based pulmonary vein (PV) isolation. We sought to characterize our experience using a novel monitoring technique for the prevention of phrenic nerve palsy.

Methods and Results—

Two hundred consecutive cryoballoon-based PV isolation procedures between October 2010 and October 2013 were studied. In addition to standard abdominal palpation during right phrenic nerve pacing from the superior vena cava, all patients underwent diaphragmatic electromyographic monitoring using surface electrodes. Cryoablation was terminated on any perceived reduction in diaphragmatic motion or a 30% decrease in the compound motor action potential (CMAP). During right-sided ablation, a ≥30% reduction in CMAP amplitude occurred in 49 patients (24.5%). Diaphragmatic motion decreased in 30 of 49 patients and was preceded by a 30% reduction in CMAP amplitude in all. In 82% of cases, this reduction in CMAP amplitude occurred during right superior PV isolation. The baseline CMAP amplitude was 946.5±609.2 mV and decreased by 13.8±13.8% at the end of application. This decrease was more marked in the 33 PVs with a reduction in diaphragmatic motion than in those without (40.9±15.3% versus 11.3±10.5%;
P
<0.001). In 3 cases, phrenic nerve palsy persisted beyond the end of the procedure, with all cases recovering within 6 months. Despite the shortened application all veins were isolated. At repeat procedure the right-sided PVs reconnected less frequently than the left-sided PVs in those with phrenic nerve palsy.

Conclusions—
Electromyographic phrenic nerve monitoring using the surface CMAP is reliable, easy to perform, and offers an early warning to impending phrenic nerve injury.
Mapping of Focal Atrial Tachycardia With an Uninterpretable Activation Map After Extensive Atrial Ablation
Authors: Ju Weizhu , Yang Bing , Chen Hongwu , Zhang Fengxiang , Gu Kai , Yu Jinbo , Li Mingfang , Yang Gang , Cao Kejiang , Chen Minglong 
Published: July 2014

Background—
Atrial tachycardias (ATs) after extensive ablation are increasingly common and challenging arrhythmias. The prolonged intra-atrial conduction time (IACT) during ATs in the milieu may complicate the mapping of focal ATs. In this present study, we aim to characterize the electrophysiological features of ATs in this unique setting and to delineate an effective mapping strategy further.

Methods and Results—
In total, 13 patients (average age, 59±7 years) in a cohort of 80 patients referred for AT ablation were selected for the study. The patients all demonstrated an undistinguishable map not ready to be interpreted the 3-dimensional mapping. A total of 13 ATs were mapped with mean tachycardia cycle length of 296±70 ms. Two activation patterns were identified, which were referred to as pseudo-macroreentry and chaotic activation. The former was a focal AT originating from the vicinity of an area of conduction block with the IACT less than the window of interest duration (4 cases; IACT/window of interest ratio range, 0.93–0.98). The latter refers to a focal AT exhibiting a disorderly color mapping display with IACT exceeding the window of interest duration (9 cases; IACT/window of interest ratio range, 1.02–1.29). The IACT was determined after resetting the annotation. All ATs were successfully eliminated at the originating site.

Conclusions—
We delineated a series of focal ATs in the setting of a significantly prolonged IACT encountered in patients after previous extensive ablation. Two activation patterns were identified, which may help facilitate the mapping of focal ATs in this setting.