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A correction to the article "Impacts of boreal hydroelectric reservoirs on seasonal climate and precipitation recycling as simulated by the CRCM5: A case study of the La Grande River watershed, Canada," by C. Irambona and colleagues is presented.

Purpose: To re-evaluate planning target volume (PTV) and organ at risk (OAR) dosimetry using Monte Carlo recalculation of treatment plans initially calculated using the Ray-Trace algorithm (effective path length method, EPL). Any differences would be correlated with known clinical outcome in terms of local failure (LF) and toxicity. Methods: Lung CK SBRT treatment plans initially calculated using an EPL algorithm (without correction for tissue inhomogeneity) were re-calculated with MC algorithm. PTV coverage and doses to OARs were compared. We reviewed PTV coverage of patients with LF, volume of the chest wall receiving ≥ 30 Gy (V30) of patients with costal tenderness or rib fracture and percentage total lung volume receiving 5 Gy (V5) and 20 Gy (V20) for patients with grade ≥ 3 pneumonitis. Results: Twenty four plans were recalculated. Median clinical follow-up on these patients was 19 months. Median prescription dose was 60 Gy (range, 48-60 Gy) in 3 fractions (range, 3-5). With EPL and MC respectively, median PTV coverage was 95 % and 91%. Thirteen patients (54%) had a 5% or greater drop in PTV coverage after recalculation (median 9%, range (+6 to -64%). However, in 2 of the 3 cases of LF PTV coverage was actually better than expected (95% PTV coverage for EPL vs. 99% by MC). The chest wall V30 increased by a median of 1.4 cc following re-calculation. Unsurprisingly, the median V30 was greater in the 12 cases of chest wall toxicity (27cc by EPL vs. 28cc by MC) that for the other patients (10 cc using either EPL or MC). Of the patients with chest wall toxicity, 3 had ≥ 5cc (range, 8.4-16cc) V30 increase on MC re-calculation. EPL and MC lung V5 and V20 differences were not significant. Two patients with pulmonary fibrosis developed grade 5 pneumonitis. Whereas median V20 was 5% (EPL and MC) (range, 2-10%) for the other patients, V20 for these 2 patients was19%(MC). Conclusion: MC recalculation predicted worse PTV coverage than EPL, however EPL inaccuracies do not appear to be implicated in LF. No significant differences were found in either chest wall V30, lung V5 or lung V20. Our work confirms that chest wall toxicity correlates with higher V30 and suggested that more severe lung constraints should be used for patients with pulmonary fibrosis. Despite improving the accuracy of patient dosimetry, the clinical benefits of MC dose calculation remain to be demonstrated. Disclosure: No significant relationships. [ABSTRACT FROM AUTHOR]

Introduction: Stereotactic body radiotherapy (SBRT) for inoperable early stage non small cell lung cancer (NSCLC) has been shown to be a safe treatment option with excellent local control. However, higher toxicities have been reported with standard SBRT fractionation for centrally located tumors. The safety and optimal fractionation of SBRT remain under investigation. Purpose: To determine initial local control, survival and toxicity rates in patients with centrally located tumors treated with SBRT at our institution using the Cyberknife® (CK) robotic radiosurgery system. Method: Thirty-nine patients with centrally located early stage NSCLC tumors were treated from 2009 to 2011. Central lesions were defined as tumors within 2 cm of the tracheobronchial tree or adjacent to the mediastinum (as per RTOG 0813 guidelines). Direct soft tissue tracking (Xsight Lung) was used in 20 (51%) patients, fiducials in 10 (26%) and tracking of adjacent vertebral bodies (Xsight Spine) in 9 (23%). Treatment doses were adjusted according to strict dose constraints to organs at risk. One patient received 48Gy in 4 fractions, 30 (77%) received 50Gy in 4-5 fractions and 8 (21%) received 60Gy in 3 fractions. Kaplan Meier curves were used for estimation of local control, overall survival and disease-specific survival. Toxicity data were graded as per the Common Terminology Criteria for Adverse Events version 3.0. Results: The median follow-up was 16 months (range, 9-35). Median age was 78 (range, 62-93). With a median tumor size of 3.2 cm (r= 2-5 cm), 24 patients (62%) were staged T1N0M0 and 15 patients (38%) had a stage T2aN0M0. Twenty-one (54%) tumors were adjacent to the mediastinum and 18 (46%) were within 2 cm of the tracheobronchial tree. At a median follow-up of 16 months, actuarial local control was 90%. The 4 patients with local recurrences received 48-50 Gy in 4-5 fractions (median biological equivalent dose of 105 Gy vs 180 Gy for patients without failure, α/β = 10). Estimated actuarial overall survival and disease-specific survival at 2 years were 75% and 79%, respectively. Three patients experienced grade 2 rib tenderness. There was no grade ≥ 3 toxicity. Conclusion: In our initial experience we have seen minimal toxicity with CK SBRT for centrally located lung tumors. Doses ≤ 50 Gy in 4-5 fractions (biological equivalent dose of 105 Gy) might be associated with higher local failure rates. Disclosure: No significant relationships. [ABSTRACT FROM AUTHOR]

Background: For patients with a higher burden of localized prostate cancer, radiation dose escalation with brachytherapy boosts have improved cancer control outcomes at the cost of urinary toxicity. We hypothesize that a focal approach to brachytherapy boosts targeting only grossly visualized tumor volumes (GTV) combined with stereotactic radiotherapy will improve quality of life (QoL) outcomes without compromising cancer control. Methods: 150 patients with intermediate or high-risk prostate cancer will be enrolled and randomized 1:1 in a cohort multiple randomized clinical trial phase 2 design. Patients are eligible if planned for standard-of-care (SOC) high dose rate (HDR) brachytherapy boost to radiotherapy (RT) with GTVs encompassing < 50% of the prostate gland. Those randomly selected will be offered the experimental treatment, consisting of focal HDR brachytherapy boost (fBT) of 13–15 Gy in 1 fraction followed by stereotactic radiotherapy (sRT) 36.25-40 Gy in 5 fractions to the prostate (+/− 25 Gy to the elective pelvis) delivered every other day. The primary endpoint is to determine if fBTsRT is superior to SOC by having fewer patients experience a minimally important decline (MID) in urinary function as measured by EPIC-26 at 1 and 2 years. Secondary endpoints include rates of toxicity measured by Common Terminology Criteria for Adverse Events (CTCAE), and failure-free survival outcomes. Discussion: This study will determine whether a novel approach for the treatment of localized prostate cancer, fBTsRT, improves QoL and merits further evaluation. Trial registration This trial was prospectively registered in ClinicalTrials.gov as NCT04100174 as a companion to registry NCT03378856 on September 24, 2019. [ABSTRACT FROM AUTHOR]

The structurally related neuropeptides, substance P, neurokinin A, and neurokinin B, belong to a family of molecules termed tachykinins and are widely distributed in the central and peripheral nervous systems. These peptides mediate their effects through three G protein coupled receptor subtypes, the neurokinin-1, neurokinin-2 and neurokinin-3 receptors, respectively. To study the physiological functions of NK3, a line of NK3 knockout mice were generated and characterized in a broad spectrum of well-established behavioral tests. In several tests, including spontaneous locomotor activity, elevated plus maze, forced swim, and hot plate, wild-type and knockout mice performed similarly. However, in several cognition tests, including passive avoidance, acquisition of conditioned avoidance responding (CAR), and the Morris water maze, NK3 knockout mice displayed deficits compared to wild-type mice. Although NK3 wild-type and knockout mice performed similarly in the training phase of the passive avoidance test, knockout mice had shorter latencies to enter the dark compartment on days 3 and 4, suggesting impaired retention. In the acquisition phase of the conditioned avoidance responding assay, NK3 knockout mice acquired the CAR task at a slower rate than wild-type mice. Once the CAR test was acquired, both NK3 wild-type and knockout mice responded similarly to clozapine and risperidone, drugs which suppress responding in this test. In the Morris water maze, NK3 knockout mice showed increased latencies to find the escape platform on day 3 of training, suggesting a modest, but significant delay in acquisition compared to wild-type mice. These studies suggest a role for NK3 in learning and memory in mice. [ABSTRACT FROM AUTHOR]

The occultation of bright star HIP9369 by the northern polar region of Jupiter was observed from four locations in North and South America, providing four data sets for ingress and egress. The inversion of the eight occultation lightcurves provides temperature profiles at different latitudes ranging from 55°N to 73.2°N. We estimate the errors on the profiles due to the uncertainties of the inversion method and compare the value of the temperature at the deepest level probed (∼ 50 μbar) with previous observations. The shape of the temperature gradient profile is found similar to previous investigations of planetary atmospheres with propagating and breaking gravity waves. We analyze the small scale structures in both lightcurves and temperature profiles using the continuous wavelet transform. The calculated power spectra of localized fluctuations in the temperature profiles show slopes close to −3 for all eight profiles. We also isolate and reconstruct the three-dimensional geometry of a single wave mode with vertical and horizontal wavelengths of respectively 3 and 70 km. The identified wave is consistent with the gravity wave regime, with a horizontal phase speed nearly parallel to the planetary meridian. Nevertheless, the dissipation of the corresponding wave in Jupiter’s stratosphere should preclude its detection at the observed levels and an acoustic wave cannot be ruled out. [Copyright &y& Elsevier]

Unlabelled: In order to characterize the role of carnitine during metabolic stress, we prospectively determined carnitine profiles in plasma and urine on admission, days 2, 5, 10 and 15, among 28 critically ill children free of any known conditions associated with secondary carnitine deficiency. More than 25% of plasma and 50% of urinary carnitine measurements were abnormal; 96% (27/28) of patients displayed on at least one occasion an abnormal [< -2 SD or > +2 SD] carnitine value in plasma. Three children had extremely low [< 10 micromol/l] free carnitine (FC) levels in plasma. Plasma esterified and FC levels on admission were not related to the risk of mortality [PRISM score], to muscle lysis [CK values], and to the caloric intake. Levels of FC and esterified carnitine in plasma were unrelated to those measured in urine.Conclusion: Abnormal plasma and urine carnitine measurements are frequently found in critically ill children; the biological significance of these perturbations remains unclear. Caution must be exercised before concluding that an abnormal carnitine value is indicative of an underlying hereditary metabolic disorder in this population. [ABSTRACT FROM AUTHOR]

Purpose To validate the feasibility of a single-fraction high-dose-rate brachytherapy (HDRBT) boost for prostate cancer using real-time transrectal ultrasound (TRUS) based planning. Material and methods From August 2012 to September 2015, 126 patients underwent a single-fraction HDRBT boost of 15 Gy using real-time TRUS based planning. External beam radiation therapy (EBRT) (37.5 Gy/15 fractions, 44 Gy/22 fractions, or 45 Gy/25 fractions) was performed before (31%) or after (69%) HDRBT boost. Genito-urinary (GU) and gastro-intestinal (GI) toxicity were assessed 4 and 12 months after the end of combined treatment using the international prostate symptom score scale (IPSS) and the common terminology criteria for adverse events (CTCAE) v3.0. Results All dose-planning objectives were achieved in 90% of patients. Prostate D90 ≥ 105% and ≤ 115% was achieved in 99% of patients, prostate V150 ≤ 40% in 99%, prostate V200 < 11% in 96%, urethra D10 < 120% for 99%, urethra V125 = 0% in 100%, and rectal V75 < 1 cm 3 in 93% of patients. Median IPSS score was 4 at baseline and did not change at 4 and 12 months after combined treatment. No patients developed ≥ grade 2 GI toxicity. With a median follow-up of 10 months, only two patients experienced biochemical failure. Among patients who didn’t receive ADT, cumulative percentage of patients with PSA ≤ 1 ng/mL at 4 and 18 months was respectively 23 and 66%. Conclusion Single-fraction HDRBT boost of 15 Gy using real-time TRUS based planning achieves consistently high dosimetry quality. [ABSTRACT FROM AUTHOR]

Background: The life courses of sexually and gender diverse individuals are shaped by a series of events that include acceptance of one's own sexual orientation or gender identity, the coming out process and socialization in the LGBTQ+ (for Lesbian, Gay, Bisexual, Transgender, Queer/Questioning, and other sexual orientations and gender identities represented by the plus sign) environment. Generally experienced in a cis-heteronormative context, this process is marked by stigma and discrimination and the social harms they can cause, including a higher-than-average prevalence of alcohol use., Objectives: To profile the alcohol use of sexually and gender diverse (SGD) youth from a life course perspective and to explore individual perceptions regarding the personal, social and cultural factors (including stigmatization and its consequences) modulating their consumption., Methodology: This qualitative descriptive study is grounded in symbolic interactionism. Semi-structured interviews lasting approximately 90 min were conducted with LGBTQ+ youth aged 18 to 30 using alcohol at least once a week. A thematic analysis was performed., Results: A total of 31 individuals aged 18-29 (average age: 25) were interviewed. The average score regarding alcohol use was 14.25 (Standard Deviation -SD-: 4-31), which corresponds to a moderate risk and indicates the need for a brief intervention. Our study documents how the higher alcohol use among LGBTQ+ youth is shaped by individual, community and cultural factors at different points in the queer life course. Among the factors influencing drinking are the emotions experienced when questioning sexual orientation and/or gender identity as well as the feelings resulting from stigma and discrimination. Our findings also indicate the influence of socializing in the queer community and meeting peers and partners, as well as that of LGBTQ+ cultural practices., Discussion: Our study indicates the need for grassroots-level interventions that work to mitigate social pressures in queer socialization contexts. Accordingly, any intervention, whether preventive or therapeutic, must consider the interplay of personal, social, community and cultural factors. Interventions regarding alcohol use must build on the strengths of community and the sense of belonging.

The ability to regulate one's emotions is integral to well-being and recent studies have documented the relationship between music and emotion regulation strategies. The purpose of this meta-analysis was to examine the impact of musicking on emotion regulation. To achieve this objective, a systematic database search for randomized control trial (RCT) studies was conducted. Eight studies that met the inclusion criteria were selected, involving 441 participants, and employing a diversity of musicking intervention strategies including listening, playing, and creating. The overall effect size was d  = 0.45; p < .01. Moderator analyses were conducted. The discussion focuses on perspectives for music education, prevention programs, and public policies for the general population and music as a potential resource contributing to well-being., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)

Purpose: This study compares conventional 192 Ir-based high dose rate brachytherapy (HDR-BT) with 169 Yb-based HDR intensity modulated brachytherapy (IMBT) for focal prostate cancer treatment. Additionally, the study explores the potential to generate less invasive treatment plans with IMBT by reducing the number of catheters needed to achieve acceptable outcomes., Methods and Materials: A retrospective dosimetric study of ten prostate cancer patients initially treated with conventional 192 Ir-based HDR-BT and 5-14 catheters was employed. RapidBrachyMCTPS, a Monte Carlo-based treatment planning system was used to calculate and optimize dose distributions. For 169 Yb-based HDR IMBT, a custom 169 Yb source combined with 0.8 mm thick platinum shields placed inside 6F catheters was used. Furthermore, dose distributions were investigated when iteratively removing catheters for less invasive treatments., Results: With IMBT, the urethra D 10 and D 0.1cc decreased on average by 15.89 and 15.65 percentage points (pp) and the rectum V 75 and D 2cc by 1.53 and 11.54 pp, respectively, compared to the conventional clinical plans. Similar trends were observed when the number of catheters decreased. On average, there was an observed increase in PTV V 150 from 2.84 pp with IMBT when utilizing all catheters to 8.83 pp when four catheters were removed. PTV V 200 increased from 0.42 to 2.96 pp on average. Hotspots in the body were however lower with IMBT compared to conventional clinical plans., Conclusions: 169 Yb-based HDR IMBT for focal treatment of prostate cancer has the potential to successfully deliver clinically acceptable, less invasive treatment with reduced dose to organs at risk., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: To assess patterns of recurrence after stereotactic ablative radiotherapy (SABR) in patient ineligible to surgery with early-stage non-small cell lung cancer (ES-NSCLC), report survival and treatment after first recurrence., Methods: We performed a retrospective analysis on 1068 patients with ES-NSCLC and 1143 lesions. Between group differences were estimated using competing risk analysis and cause-specific hazard ratios were calculated. Overall survival (OS) after first recurrence was calculated., Results: Median follow-up was 37.6 months. Univariate analysis demonstrated that ultra-central location was associated with higher risk of regional recurrence (RR) and distant metastasis (DM) (p = 0.004 and 0.01). Central lesions were associated with higher risk of local recurrence (LR) and RR (p < 0.001). Ultra-central lesions were associated with shorter OS (p = 0.002) compared to peripheral lesions. In multivariate analysis, central location was the only factor associated with increased LR and RR risks (p = 0.016 and 0.005). Median OS after first recurrence was 14.8 months. There was no difference in OS after first recurrence between ultra-central, central, and peripheral lesions (p = 0.83). Patients who received a second SABR course had an OS of 51.3 months, compared to 19.5 months with systemic therapy and 8.1 months with supportive care (p < 0.0001)., Discussion: The main prognostic factor for LR and RR risks was central location. Ultra-central and central tumors might benefit from treatment intensification strategies such as dose escalation and/or addition of systemic therapy to improve radiotherapy outcomes. After a first recurrence post SABR, patients with contralateral lung recurrences and those who were eligible to receive a second course of SABR had improved OS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Background and Purpose: Locally recurrent prostate cancer after radiotherapy merits an effective salvage strategy that mitigates the risk of adverse events. We report outcomes of a cohort enrolled across two institutions investigating MRI-guided tumor-targeted salvage high dose rate brachytherapy (HDR-BT)., Materials and Methods: Analysis of a prospective cohort of 88 patients treated across two institutions with MRI-guided salvage HDR-BT to visible local recurrence after radiotherapy (RT). Tumor target dose ranged from 22-26 Gy, using either an integrated boost (ibBT) or focal technique (fBT), delivered in two implants over a median of 7 days. Outcome metrics included cancer control and toxicity (CTCAE). Quality of life (QoL-EPIC) was analyzed in a subset., Results: At a median follow-up of 35 months (6 -134), 3 and 5-year failure-free survival (FFS) outcomes were 67% and 49%, respectively. At 5 years, fBT was associated with a 17% cumulative incidence of local failure (LF) outside the GTV (vs. 7.8% ibBT, p=0.14), while LF within the GTV occurred in 13% (vs. 16% ibBT, p=0.81). Predictors of LF outside fBT volumes included pre-salvage PSA>7 ng/mL (p=0.03) and interval since RT less than 5 years (p=0.04). No attributable grade 3 events occurred, and ibBT was associated with a higher rate of grade 2 toxicity (p<0.001), and trend towards a larger reduction in QoL sexual domain score (p=0.07), compared to fBT., Conclusion: A tumor-targeted HDR-BT salvage approach achieved favorable cancer control outcomes. While a fBT was associated with less toxicity, it may be best suited to a subgroup with lower PSA at later recurrence. Tumor targeted dose escalation may be warranted., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ménard, Navarro-Domenech, Liu, Joseph, Barkati, Berlin, Delouya, Taussky, Beauchemin, Nicolas, Kadoury, Rink, Raman, Sundaramurthy, Weersink, Beliveau-Nadeau, Helou and Chung.)

Background and Purpose: Advances in high-dose-rate brachytherapy to treat prostate cancer hinge on improved accuracy in navigation and targeting while optimizing a streamlined workflow. Multimodal image registration and electromagnetic (EM) tracking are two technologies integrated into a prototype system in the early phase of clinical evaluation. We aim to report on the system's accuracy and workflow performance in support of tumor-targeted procedures., Materials and Methods: In a prospective study, we evaluated the system in 43 consecutive procedures after clinical deployment. We measured workflow efficiency and EM catheter reconstruction accuracy. We also evaluated the system's MRI-TRUS registration accuracy with/without deformation, and with/without y-axis rotation for urethral alignment at initialization., Results: The cohort included 32 focal brachytherapy and 11 integrated boost whole-gland implants. Mean procedure time excluding dose delivery was 38 min (range: 21-83) for focal, and 56 min (range: 38-89) for whole-gland implants; stable over time. EM catheter reconstructions achieved a mean difference between computed and measured free-length of 0.8 mm (SD 0.8, no corrections performed), and mean axial manual corrections 1.3 mm (SD 0.7). EM also enabled the clinical use of a non or partially visible catheter in 21% of procedures. Registration accuracy improved with y-axis rotation for urethral alignment at initialization and with the elastic registration (mTRE 3.42 mm, SD 1.49)., Conclusion: The system supported tumor-targeting and was implemented with no demonstrable learning curve. EM reconstruction errors were small, correctable, and improved with calibration and control of external distortion sources; increasing confidence in the use of partially visible catheters. Image registration errors remained despite rotational alignment and deformation, and should be carefully considered., (Copyright © 2021 Elsevier B.V. All rights reserved.)

There is scarce research on children and youth with sexual behavior problems (SBP) and their developmental antecedents and the research that does exist is mostly retrospective and correlational. While prior research focused on the central role of sexual victimization, recent research suggests that young persons with SBP are exposed to a series of adversities not limited to child sexual victimization and require multifaceted assessment and intervention using a developmental life course perspective. The current study includes an examination of the complete longitudinal sequence of child protective service (CPS) investigations involving young persons with SBP. The study is based on a sample of 957 youth referred to the CPS in Quebec, Canada. The data include their longitudinal sequence of referrals from birth to age 18. Semi-parametric analyses identified four trajectories of referrals with significant differences in terms of onset, frequency, types of life adversity, and polyvictimization. The trajectories suggest that a range of developmental profiles characterize young persons with SBP, with SBP often occurring after CPS contacts for compromising issues other than sexual victimization, especially parental neglect and serious behavior problems. Of importance, polyvictimization was relatively common for this group throughout childhood and adolescence, which highlights the multiintervention needs of this population., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

There is little information about the onset and the developmental course of child sexual behavior problems (SBPs), including sexually intrusive behaviors (SIBs). Using data from the Vancouver Longitudinal Study on the Psychosocial Development of Children, the current study examined the presence of distinct patterns of sexual development among children. A normative sample of preschoolers ( N = 354) with a small clinical subsample were followed from age 3 to 8 with repetitive measurements of sexual behaviors using a revised version of Child Sexual Behavior Inventory. Semiparametric group-based modeling identified four distinct sexual development trajectories: the very low (10.5%), the low declining (27.8%), the moderate stable (48.3%), and the high-rate increasing (13.4%). In contrast to the other developmental trajectories found, the high-rate-increasing pattern showed that sexual behaviors became increasingly extensive after school entry. Children characterized by this developmental pattern, especially boys, were more likely to be involved in SIBs after elementary school entry than those in the other groups. Findings highlight the presence of multiple developmental trajectories of sexual development with significantly different behavioral patterns after school entry.

Introduction: Despite advances in treatment, notably in systemic therapy, the prognosis of pancreatic adenocarcinoma (PADC) remains dismal. Stereotactic body radiotherapy (SBRT) is an emerging tool in the complex management of PADC. We review outcomes of SBRT for PADC at our institution., Methods: We reviewed patients treated with SBRT for either unresectable PADC or locally recurrent PADC after surgery. Treatment was delivered using a robotic radiosurgery system with respiratory tracking. The median prescribed dose was 30 Gy (30-35 Gy), delivered in 5-6 fractions. Toxicities were reported as per CTCAE v4.0. Survival was estimated using the Kaplan-Meier method., Results: Between October 2010 and March 2016, 21 patients were treated at our institution. The median follow-up was 7 months (range: 1-28). The 1-year local control rate was 57%. The 1-year overall survival was 25% for locally advanced patients and 67% for those with local recurrences (p = 0.27). Eighty percent of cancer related deaths were due to metastatic progression. Five patients (24%) had Grade I-II gastrointestinal acute toxicity; one patient had fatal gastrointestinal bleeding 6 months after SBRT., Conclusion: In PADC, fractionated SBRT dose schedules near 30 Gy may strike the best balance of local control and bowel toxicity. More work is required to integrate pancreatic SBRT with modern systemic therapy., (Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. All rights reserved.)

Purpose To compare the impact of the fusion of intraoperative transrectal ultrasound (TRUS) images with day 30 computed tomography (CT) and magnetic resonance imaging (MRI) on prostate volume and dosimetry. Methods and materials Seventy-five consecutive patients with CT and MRI obtained on day 30 with a Fast Spin Echo T2-weighted magnetic resonance (MR) sequence were analyzed. A rigid manual registration was performed between the intraoperative TRUS and day-30 CT based on the prostate volume. A second manual rigid registration was performed between the intraoperative TRUS and the day-30 MRI. The prostate contours were manually modified on CT and MRI. The difference in prostate volume and dosimetry between CT and MRI were compared. Results Prostate volume was on average 8% (standard deviation (SD) ± 16%) larger on intraoperative TRUS than on CT and 6% (18%) larger than on MRI. In 48% of the cases, the difference in volume on CT was > 10% compared to MRI. The difference in prostate volume between CT and MRI was inversely correlated to the difference in D90 (minimum dose that covers 90% of the prostate volume) between CT and MRI (r = -0.58, P < .001). A D90 < 90% was found in 5% (n = 4) on MRI and in 10% (n = 7) on CT (Fisher exact test one-sided P = .59), but in no patient was the D90 < 90% on both MRI and CT. Conclusions When fusing TRUS images with CT and MRI, the differences in prostate volume between those modalities remain clinically important in nearly half of the patients, and this has a direct influence on how implant quality is evaluated., Competing Interests: The authors have declared that no competing interests exist.

The purpose of this study is to evaluate the impact of a novel tissue characterization method using dual-energy over single-energy computed tomography (DECT and SECT) on Monte Carlo (MC) dose calculations for low-dose rate (LDR) prostate brachytherapy performed in a patient like geometry. A virtual patient geometry is created using contours from a real patient pelvis CT scan, where known elemental compositions and varying densities are overwritten in each voxel. A second phantom is made with additional calcifications. Both phantoms are the ground truth with which all results are compared. Simulated CT images are generated from them using attenuation coefficients taken from the XCOM database with a 100 kVp spectrum for SECT and 80 and 140Sn kVp for DECT. Tissue segmentation for Monte Carlo dose calculation is made using a stoichiometric calibration method for the simulated SECT images. For the DECT images, Bayesian eigentissue decomposition is used. A LDR prostate brachytherapy plan is defined with 125 I sources and then calculated using the EGSnrc user-code Brachydose for each case. Dose distributions and dose-volume histograms (DVH) are compared to ground truth to assess the accuracy of tissue segmentation. For noiseless images, DECT-based tissue segmentation outperforms the SECT procedure with a root mean square error (RMS) on relative errors on dose distributions respectively of 2.39% versus 7.77%, and provides DVHs closest to the reference DVHs for all tissues. For a medium level of CT noise, Bayesian eigentissue decomposition still performs better on the overall dose calculation as the RMS error is found to be of 7.83% compared to 9.15% for SECT. Both methods give a similar DVH for the prostate while the DECT segmentation remains more accurate for organs at risk and in presence of calcifications, with less than 5% of RMS errors within the calcifications versus up to 154% for SECT. In a patient-like geometry, DECT-based tissue segmentation provides dose distributions with the highest accuracy and the least bias compared to SECT. When imaging noise is considered, benefits of DECT are noticeable if important calcifications are found within the prostate.

Purpose: Our preferred treatment for juxtapapillary choroidal melanoma is stereotactic radiotherapy. We aim to describe our immobilization system and quantify its reproducibility., Materials and Methods: Patients were identified in our radiosurgery database. Patients were imaged at computed tomography simulator with an in-house system which allows visual monitoring of the eye as the patient fixates a small target. All patients were reimaged at least once prior to and/or during radiotherapy. The patients were treated on the CyberKnife system, 60 Gy in 10 daily fractions, using skull tracking in conjunction with our visual monitoring system. In order to quantify the reproducibility of the eye immobilization system, computed tomography scans were coregistered using rigid 6-dimensional skull registration. Using the coregistered scans, x, y, and z displacements of the lens/optic nerve insertion were measured. From these displacements, 3-dimensional vectors were calculated., Results: Thirty-four patients were treated from October 2010 to September 2015. Thirty-nine coregistrations were performed using 73 scans (2-3 scans per patient). The mean displacements of lens and optic nerve insertion were 0.1 and 0.0 mm. The median 3-dimensional displacements (absolute value) of lens and nerve insertion were 0.8 and 0.7 mm (standard deviation: 0.5 and 0.6 mm). Ninety-eight percent of 3-dimensional displacements were below 2 mm (maximum 2.4 mm). The calculated planning target volume (PTV) margins were 0.8, 1.4, and 1.5 mm in the anterior-posterior, craniocaudal, and right-left axes, respectively. Following this analysis, no further changes have been applied to our planning margin of 2 to 2.5 mm as it is also meant to account for uncertainties in magnetic resonance imaging to computed tomography registration, skull tracking, and also contouring variability., Conclusion: We have found our stereotactic eye immobilization system to be highly reproducible (<1 mm) and free of systematic error.

Purpose: To investigate the incidence and predictive factors of severe radiation pneumonitis (RP) after stereotactic ablative radiation therapy (SABR) in early-stage lung cancer patients with preexisting radiological interstitial lung disease (ILD)., Methods and Materials: A retrospective analysis of patients with stage I lung cancer treated with SABR from 2009 to 2014 was conducted. Interstitial lung disease diagnosis and grading was based on pretreatment high-resolution computed tomography imaging. A central review of pretreatment computed tomography by a single experienced thoracic radiologist was conducted. Univariate and multivariate analyses were conducted to determine potential predictors of severe RP in patients with ILD., Results: Among 504 patients treated with SABR in this period, 6% were identified as having preexisting ILD. There was a 4% rate of ≥ grade 3 RP in the entire cohort. Interstitial lung disease was associated with increased risk of ≥ grade 3 RP (32% in ILD+ vs 2% in ILD-, P < .001). Five patients (21%) with ILD developed grade 5 RP. Lower forced expiratory volume in 1 second and forced vital capacity, higher V5Gy and mean lung dose, presence of severe radiological ILD, and combined emphysema were significant predictors of ≥ grade 3 RP on univariate analysis; only forced expiratory volume in 1 second remained on multivariate analysis., Conclusion: Interstitial lung disease is associated with an increased risk of severe RP after SABR. Chest imaging should be reviewed for ILD before SABR, and the risk of fatal RP should be carefully weighed against the benefits of SABR in this subgroup., (Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)

Background: Del Nido cardioplegia (DC) offers prolonged cardiac protection with single-dose administration and has had a long safety record in pediatric cardiac surgery. However, its application in the adult population has thus far been limited. We evaluated the efficacy of cardiac protection and clinical outcomes of DC vs blood cardioplegia (BC) in adult coronary artery bypass graft (CABG) patients., Methods: Clinical outcomes of 100 consecutive isolated CABG patients who received DC (May to September 2014) were compared with the previous 100 consecutive isolated CABG patients receiving BC (December 2013 to April 2014). Propensity matching yielded 82 pairs. The same surgeons operated on all patients. Clinical patient characteristics and data were extracted from our local The Society of Thoracic Surgeons database and the electronic medical record., Results: Preoperative characteristics were similar between BC and DC patients before and after propensity matching. BC patients received anterograde and retrograde cardioplegia, whereas DC was delivered anterograde, with 92 of 100 patients receiving a single dose only. Inotropic support upon arrival to the recovery unit did not differ between BC and DC (0.28 ± 0.11 vs 0.27 ± 0.11 μg/kg/min milrinone [p = 0.8] and 0.05 ± 0.03 vs 0.05 ± 0.03 μg/kg/min norepinephrine [p = 0.7]), nor did postoperative troponin T levels (0.56 ± 0.48 vs 0.70 ± 1.27 ng/mL; p = 0.3). The peak intraoperative glucose level was higher in BC (209.8 ± 40.4 mg/dL) than in DC (161.4 ± 42.3 mg/dL) patients (p < 0.001). No patients died in either group, and the postoperative incidence of atrial fibrillation, stroke, reoperation for bleeding, and prolonged intubation did not differ between the groups before and after matching. There was also no difference in the postoperative ejection fraction between the groups (0.51 ± 0.13 vs 0.47 ± 0.13 for BC and DC, respectively; p = 0.17)., Conclusions: In our initial experience, DC provided equivalent myocardial protection and clinical outcomes to BC in adult isolated CABG patients. DC was associated with lower cardiopulmonary bypass glucose levels than BC and demonstrated the feasibility of single-dose administration for routine coronary operations., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Introduction: The aim of our study was to review seed loss and its impact on dosimetry as well as the influence of the treating physician on seed loss and dosimetry in patients treated with prostate brachytherapy using permanent loose (125)I implant., Patients and Methods: We analyzed 1087 consecutive patients treated by two physicians between July 2005 and April 2015 at a single institution. Pelvic fluoroscopic imaging was done 30 days post implant and a chest X-ray when seed loss was observed., Results: Seed loss occurred in 19.4 % of patients: in 20.0 % of implants done by the most experienced physician and in 17.2 % by the less experienced physician (p = 0.4) and migration to the thorax occurred in 5.9 % (6.9 vs. 2.2 %, p = 0.004). The mean seed loss rate was 0.57 % [standard deviation (SD) 1.39] and the mean rate of seeds in the thorax was 0.14 % (SD 0.65). The most experienced physician had a higher mean number of seeds lost: 0.36 versus 0.25 (p = 0.055), and a higher mean number of seed migration to the thorax: 0.1 versus 0.02 (p < 0.001). When at least one seed was lost, a decrease of 4.2 Gy (p < 0.001) in the D90 and a decrease of 3.5 % (p = 0.002) in the V150 was observed., Conclusion: We found a significant decrease in V150 and D90 with the occurrence of seed loss. Furthermore, we found a difference in seed migration among the physicians demonstrating that seed loss is operator dependant.