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Purpose: The RefleXion X1 is a novel radiotherapy machine designed for image‐guided radiotherapy (IGRT) and biology‐guided radiotherapy (BgRT). Its treatment planning system (TPS) generates IMRT and SBRT plans for a 6MV‐FFF beam delivered axially via 50 firing positions with the couch advancing every 2.1 mm. The purpose of this work is to report the TPS commissioning results for the first clinical installation of RefleXion™ X1. Methods: CT images of multiple phantoms were imported into the RefleXion TPS to evaluate the accuracy of data transfer, anatomical modeling, plan evaluation, and dose calculation. Comparisons were made between the X1, Eclipse™, and MIM™. Dosimetric parameters for open static fields were evaluated in water and heterogeneous slab phantoms. Representative clinical IMRT and SBRT cases were planned and verified with ion chamber, film, and ArcCHECK@ measurements. The agreement between TPS and measurements for various clinical plans was evaluated using Gamma analysis with a criterion of 3%/2 mm for ArcCHECK@ and film. End‐to‐end (E2E) testing was performed using anthropomorphic head and lung phantoms. Results: The average difference between the TPS‐reported and known HU values was −1.4 ± 6.0 HU. For static fields, the agreements between the TPS‐calculated and measured PDD10, crossline profiles, and inline profiles (FWHM) were within 1.5%, 1.3%, and 0.5 mm, respectively. Measured output factors agreed with the TPS within 1.3%. Measured and calculated dose for static fields in heterogeneous phantoms agreed within 2.5%. The ArcCHECK@ mean absolute Gamma passing rate was 96.4% ± 3.4% for TG 119 and TG 244 plans and 97.8% ± 3.6% for the 21 clinical plans. E2E film analysis showed 0.8 mm total targeting error for isocentric and 1.1 mm for off‐axis treatments. Conclusions: The TPS commissioning results of the RefleXion X1 TPS were within the tolerances specified by AAPM TG 53, MPPG 5.a, TG 119, and TG 148. A subset of the commissioning tests has been identified as baseline data for an ongoing QA program. [ABSTRACT FROM AUTHOR]

Objective: Occupational violence and aggression (OVA) in the ED is an issue of global concern and increasing incidence. The empirical evidence for the relationship between the lunar cycle and 'lunatics' remains equivocal. The present study aims to examine the association between OVA in ED and the full moon (FM). Methods: Data on all presentations were extracted from The Alfred Hospital ED records for consecutive patients over a 3‐year period (January 2013–December 2015). The primary outcome of the present study is OVA among patients in the ED. Univariable and multivariable logistic regression were used to determine the association between aspects of the lunar cycle and OVA. Results: There were 184 059 ED presentations during the 3 years, 6234 (3.4%) of which occurred on a FM. There were 1853 episodes of OVA, 57 (3.1%) of which occurred on a FM. OVA among patients presenting to ED was not associated with the FM (adjusted odds ratio [OR] 0.92 [95% confidence interval 0.70–1.20]; P = 0.53). However, the first quarter (FQ) (adjusted OR 1.38 [1.11–1.72]; P < 0.01) and third quarter (TQ) (adjusted OR 1.29 [95% confidence interval 1.03–1.62]; P = 0.03) moons of the lunar cycle were independently associated with OVA. Conclusions: Contrary to traditional beliefs, the FQ and TQ of the lunar cycle but not the FM were associated with OVA. This highlights a relatively unexplored relationship that has previously been overshadowed by the FM in the literature. Prediction models of violence in the ED could consider incorporating the FQ and TQ of the lunar cycle in their models. [ABSTRACT FROM AUTHOR]

Aims: There is increasing evidence showing the importance of long‐acting injectable antipsychotics in the management of schizophrenia, especially in terms of improving patient medication compliance. A panel of experienced clinicians in Hong Kong mapped out a set of consensus statements with an aim to facilitate the understanding and use of long‐acting injectable antipsychotics among local physicians. Methods: Eight discussion areas regarding long‐acting injectable antipsychotics were selected by the chairman of the consensus group. A series of meetings were held for the panelists to discuss the published literature and their clinical experience, followed by the drafting of consensus statements. At the final meeting, each consensus statement was voted on anonymously by all members based on its practicability of recommendation in Hong Kong. Results: A total of 12 consensus statements on the rational use of long‐acting injectable antipsychotics were established and accepted by the consensus group. Conclusion: The consensus statements aim to provide practical guidance for Hong Kong physicians on the use of long‐acting injectable antipsychotics in schizophrenia patients. These statements may also serve as a reference for doctors in other parts of the Asia–Pacific region. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of CT protocol and in‐room x‐ray technique on CyberKnife® (Accuray Inc.) tracking accuracy by evaluating end‐to‐end tests. Methods: End‐to‐end (E2E) tests were performed for the different tracking methods (6D skull, fiducial, spine, and lung) using an anthropomorphic head phantom (Accuray Inc.) and thorax phantom (CIRS Inc.). Bolus was added to the thorax phantom to simulate a large patient and to evaluate the performance of lung tracking in a more realistic condition. The phantoms were scanned with a Siemens Sensation Open 24 slice CT at low dose (120 kV, 70 mAs, 1.5 mm slice thickness) and high dose (120 kV, 700 mAs, 1.5 mm slice thickness) to generate low‐dose and high‐dose digitally reconstructed radiographs (DRRs). The difference in initial phantom alignment, Δ(Align), and in total targeting accuracy, E2E, were obtained for all tracking methods with low‐ and high‐dose DRRs. Additionally, Δ(Align) was determined for different in‐room x‐ray imaging techniques (0.5 to 50 mAs and 100 to 140 kV) using a low‐dose lung tracking plan. Results: Low‐dose CT scans produced images with high noise; however, for these phantoms the targets could be easily delineated on all scans. End‐to‐end results were less than 0.95 mm for all tracking methods and all plans. The greatest difference in initial alignment Δ(Align) and E2E results between low‐ and high‐dose CT protocols was 0.32 and 0.24 mm, respectively. Similar results were observed with a large thorax phantom. Tracking using different in‐room x‐ray imaging techniques (mAs) corresponding to low exposures (resulting in high image noise) or high exposure (resulting in image saturation) had alignment accuracy Δ(Align) greater than 1 mm. Conclusions: End‐to‐end targeting accuracy within tolerance (<0.95 mm) was obtained for all tracking methods using low‐dose CT protocols, suggesting that CT protocol should be set by target contouring needs. Additionally, high tracking accuracy was achieved for in‐room x‐ray imaging techniques that produce high‐quality images. [ABSTRACT FROM AUTHOR]

Aripiprazole, a dopamine partial agonist, is a second‐generation anti‐psychotic that is widely used for the treatment of schizophrenia and other psychotic disorders. A group of psychiatric experts in Hong Kong developed a set of consensus statements, aiming to facilitate the understanding of clinical properties and usages of aripiprazole among local physicians. Of note, because aripiprazole long‐acting injectable has been available locally not long before the establishment of the consensus panel, which limited the discussion on its use in the local context, the consensus statements were focused primarily on oral aripiprazole. To draft the consensus statements, the panellists discussed the published evidence and their clinical experience regarding aripiprazole in a series of meetings based on several areas. At the final meeting, each drafted statement was voted on anonymously by all panellists based on its practicability of recommendation in Hong Kong. A set of consensus statements on the characteristics and clinical use of aripiprazole was established and accepted by the panel. These statements serve to provide a practical reference for physicians in Hong Kong, and possibly other parts of the Asia‐Pacific region, on the use of aripiprazole in people with schizophrenia spectrum disorders and other psychotic problems. [ABSTRACT FROM AUTHOR]

The aim of this systematic review and meta‐analysis was to evaluate the outcomes of patients who are not transported to hospital following ambulance attendance. A database search was conducted using PubMed, Medline, Embase, CINAHL and Cochrane Library. Studies were included if they analysed the outcomes of patients who were not transported following ambulance attendance. The primary outcome of this review was subsequent presentation to an ED following a non‐transport decision. Secondary outcome measures included hospital admission, subsequent presentation to alternative service provider (e.g. private physician), and death at follow up. The search yielded 1953 non‐duplicate articles, of which 10 met the inclusion criteria. Three studies specified that the non‐transport decision was emergency medical services (EMS)‐initiated, seven studies did not specify. Meta‐analysis found substantial heterogeneity between estimates (I2 >50%) that was likely because of differences in study design, length of follow up, patient demographic and sample size. Between 5% and 46% (pooled estimate 21%; 95% CI 11–31%) of non‐transport patients subsequently presented to ED. Few (pooled estimate 8%; 95% CI 5–12%) EMS‐initiated non‐transport patients were admitted to hospital compared to the unspecified group (pooled estimate 40%; 95% CI 7–72%). Mortality rates were low across included studies. Studies found varying estimates for the proportion of patients discharged at the scene that subsequently presented to ED. Few patients were admitted to hospital when the non‐transport decision was initiated by EMS, indicating EMS triage is a relatively safe practice. More research is needed to elucidate the context of non‐transport decisions and improve access to alternative pathways. [ABSTRACT FROM AUTHOR]

Purpose Parametric response map (PRM) analysis of functional imaging has been shown to be an effective tool for early prediction of cancer treatment outcomes and may also be well-suited toward guiding personalized adaptive radiotherapy (RT) strategies such as sub-volume boosting. However, the PRM method was primarily designed for analysis of longitudinally acquired pairs of single-parameter image data. The purpose of this study was to demonstrate the feasibility of a generalized parametric response map analysis framework, which enables analysis of multi-parametric data while maintaining the key advantages of the original PRM method. Methods MRI-derived apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) maps acquired at 1 and 3-months post-RT for 19 patients with high-grade glioma were used to demonstrate the algorithm. Images were first co-registered and then standardized using normal tissue image intensity values. Tumor voxels were then plotted in a four-dimensional Cartesian space with coordinate values equal to a voxel's image intensity in each of the image volumes and an origin defined as the multi-parametric mean of normal tissue image intensity values. Voxel positions were orthogonally projected onto a line defined by the origin and a pre-determined response vector. The voxels are subsequently classified as positive, negative or nil, according to whether projected positions along the response vector exceeded a threshold distance from the origin. The response vector was selected by identifying the direction in which the standard deviation of tumor image intensity values was maximally different between responding and non-responding patients within a training dataset. Voxel classifications were visualized via familiar three-class response maps and then the fraction of tumor voxels associated with each of the classes was investigated for predictive utility analogous to the original PRM method. Independent PRM and MPRM analyses of the contrast-enhancing lesion (CEL) and a 1 cm shell of surrounding peri-tumoral tissue were performed. Prediction using tumor volume metrics was also investigated. Leave-one-out cross validation (LOOCV) was used in combination with permutation testing to assess preliminary predictive efficacy and estimate statistically robust P-values. The predictive endpoint was overall survival (OS) greater than or equal to the median OS of 18.2 months. Results Single-parameter PRM and multi-parametric response maps (MPRMs) were generated for each patient and used to predict OS via the LOOCV. Tumor volume metrics ( P ≥ 0.071 ± 0.01) and single-parameter PRM analyses ( P ≥ 0.170 ± 0.01) were not found to be predictive of OS within this study. MPRM analysis of the peri-tumoral region but not the CEL was found to be predictive of OS with a classification sensitivity, specificity and accuracy of 80%, 100%, and 89%, respectively ( P = 0.001 ± 0.01). Conclusions The feasibility of a generalized MPRM analysis framework was demonstrated with improved prediction of overall survival compared to the original single-parameter method when applied to a glioblastoma dataset. The proposed algorithm takes the spatial heterogeneity in multi-parametric response into consideration and enables visualization. MPRM analysis of peri-tumoral regions was shown to have predictive potential supporting further investigation of a larger glioblastoma dataset. [ABSTRACT FROM AUTHOR]

Set-up accuracy of different image-guidance (IG) protocols using reduced imaging frequency was compared with daily IG. Anatomical characteristics were investigated for their potential to help select the suitable IG protocols for individual patients. Set-up corrections from 26 prostate cancer patients treated with daily IG on helical tomotherapy were used to simulate IG protocols with reduced imaging frequency, where average set-up corrections from a subset of initial IG sessions were used for subsequent fractions with no IG. Residual set-up error, the difference between the average set-up correction and the actual correction required, was used to evaluate the accuracy of each protocol. Adaptive treatment margins required to encompass these errors were calculated. Body mass index and daily bladder and rectum cross-sectional areas (CSAs) were measured, and their correlations with set-up corrections were evaluated. We also investigated the use of reduced imaging schedules to estimate changes in bladder and rectum CSAs. As expected, residual set-up errors and adaptive treatment margins were effectively reduced with frequent imaging. For the majority of patients (81%), 10 IG sessions were sufficient to reduce residual set-up errors to within the adaptive treatment margins. Daily IG was more suitable than using a reduced IG protocol for a minority of patients (19%) with residual set-up errors that consistently exceeded the margins for >10% of fractions. These patients could be identified with 10 imaging sessions via the analysis of anatomical variations. The accuracy of modified IG protocols should be validated in the context of institutional practice regarding patient set-up and bowel/bladder preparation. [ABSTRACT FROM AUTHOR]

The face is one of the three regions most frequently affected by congenital defects in humans. To understand the molecular mechanisms involved, it is necessary to have a more complete picture of gene expression in the embryo. Here, we use microarrays to profile expression in chicken facial prominences, post neural crest migration and before differentiation of mesenchymal cells. Chip-wide analysis revealed that maxillary and mandibular prominences had similar expression profiles while the frontonasal mass chips were distinct. Of the 3094 genes that were differentially expressed in one or more regions of the face, a group of 56 genes was subsequently validated with quantitative polymerase chain reaction (QPCR) and a subset examined with in situ hybridization. Microarrays trends were consistent with the QPCR data for the majority of genes (81%). On the basis of QPCR and microarray data, groups of genes that characterize each of the facial prominences can be determined. Developmental Dynamics 239:574-591, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]