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Whole-brain radiation therapy (WBRT) plays an important role in patients with diffusely metastatic intracranial disease. Whether the extent of the radiation field design to C1 or C2 affects parotid dose and risk for developing xerostomia is unknown. The goal of this study is to examine the parotid dose based off of the inferior extent of WBRT field to either C1 or C2. Patients treated with WBRT with either 30 Gy or 37.5 Gy from 2011 to 2014 at a single institution were examined. Parotid dose constraints were compared with Radiation Therapy Oncology Group (RTOG) 0615 nasopharyngeal carcinoma for a 33-fraction treatment: mean

We address the problem of navigating a set (fleet) of aircraft in an aerial route network so as to bring each aircraft to its destination at a specified time and with minimal distance separation assured between all aircraft at all times. The speed range, initial position, required destination, and required time of arrival at destination for each aircraft are assumed provided. Each aircraft's movement is governed by a controlled differential equation (state equation). The problem consists in choosing for each aircraft a path in the route network and a control strategy so as to meet the constraints and reach the destination at the required time. The main contribution of the paper is a model that allows to recast this problem as a decoupled collection of problems in classical optimal control and is easily generalized to the case when inertia cannot be neglected. Some qualitative insight into solution behavior is obtained using the Pontryagin Maximum Principle. Sample numerical solutions are computed using a numerical optimal control solver. The proposed model is first step toward increasing the fidelity of continuous time control models of air traffic in a terminal airspace. The Pontryagin Maximum Principle implies the polygonal shape of those portions of the state trajectories away from those states in which one or more aircraft pair are at minimal separation. The model also confirms the intuition that, the narrower the allowed speed ranges of the aircraft, the smaller the space of optimal solutions, and that an instance of the optimal control problem may not have a solution at all (i.e., no control strategy that meets the separation requirement and other constraints).

Stereotactic radiosurgery (SRS) should be considered in the comprehensive treatment paradigm for all patients with brain metastases. This technique has proven benefits for local tumor control in individuals with as many as 4 lesions, and when combined with structured radiographic follow-up, will likely preserve a better quality of life for appropriately selected patients. Institutions and physicians treating patients with brain metastases should have the capability of safely performing SRS and individual cases should be prospectively reviewed by multidisciplinary teams to provide the best comprehensive care.

Purpose To integrate imaging performance characteristics, specifically sensitivity and specificity, of magnetic resonance angiography (MRA) and digital subtraction angiography (DSA) into arteriovenous malformation (AVM) radiosurgery planning and evaluation. Methods and Materials Images of 10 patients with AVMs located in critical brain areas were analyzed in this retrospective planning study. The image findings were first used to estimate the sensitivity and specificity of MRA and DSA. Instead of accepting the imaging observation as a binary (yes or no) mapping of AVM location, our alternative is to translate the image into an AVM probability distribution map by incorporating imagers' sensitivity and specificity, and to use this map as a basis for planning and evaluation. Three sets of radiosurgery plans, targeting the MRA and DSA positive overlap, MRA positive, and DSA positive were optimized for best conformality. The AVM obliteration rate (ORAVM) and brain complication rate served as endpoints for plan comparison. Results In our 10-patient study, the specificities and sensitivities of MRA and DSA were estimated to be (0.95, 0.74) and (0.71, 0.95), respectively. The positive overlap of MRA and DSA accounted for 67.8% ± 4.9% of the estimated true AVM volume. Compared with plans targeting MRA and DSA–positive overlap, plans targeting MRA-positive or DSA-positive improved ORAVM by 4.1% ± 1.9% and 15.7% ± 8.3%, while also increasing the complication rate by 1.0% ± 0.8% and 4.4% ± 2.3%, respectively. Conclusions The impact of imagers' quality should be quantified and incorporated in AVM radiosurgery planning and evaluation to facilitate clinical decision making.

A prototype decision support tool for terminal area air traffic controllers, referred to as the Final Approach Spacing Tool (FAST), was recently evaluated in operation with live air traffic at the Dallas/Fort Worth, Texas Airport. Controllers utilized FAST’s runway and sequence advisories to manage and control arrival traffic during more than twenty-five peak rush traffic periods. This paper presents the results of these tests, describing data on FAST’s impact on airport capacity, in-trail separation on final approach, safety, and controller workload. Results demonstrate airport throughput increases of more than 13 percent with no negative impact on controller workload or safety.

Orbital and Periorbital Complications of Proton Beam Radiation Therapy for Intraocular Tumor Y.J. Choi, S. Kim, H.K. Choung, and Y.S. Yu; Department of Ophthalmology, Kangdong Sacred Heart Hospital, Hallym University Medical Center, Seoul, South Korea, Department of Radiation Oncology, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, South Korea, Department of Ophthalmology, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, South Korea, Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea, Seoul, South Korea, Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea, Seoul, South Korea

From 1979 through July 1983, 859 patients were enrolled in a Phase III RTOG Protocol (7916) evaluating the role of Misonidazole combined with radiation in the treatment of brain metastasis. Patients were randomized to one of four treatment arms 3.0 Gy × 10 fractions with or without 1 g/m 2 of Misonidazole [total 10 g/m2] versus 5.0 Gy × 6 fractions with or without 2 g/m 2 of Misonidazole) [total 12 g/m 2 ]. Among the 779 analyzable cases, 63% had a lung primary and 12% had breast. Of the histologic types, 43% were adenocarcinoma and 24% were squamous cell. Seventy-eight percent had a Karnofsky of greater than 70. Of the 779 cases, 773 are dead (99%). Median survival is 3.9 months, with 60% alive at 3 months, 35% at 6 months, and 15% at 1 year. Survival was evaluated by treatment arm, Misonidazole status, and fractionation scheme; none showed any statistical significance. Favorable prognostic factors were assessed (age less than 60, Karnofsky of 70–100, controlled primary and brain metastasis only) in each treatment arm and no difference was found. Brain metastasis was cause of death in 13, and 19–33% of patients were retreated. Because up to 13 of the patients in this study died secondary to uncontrolled brain metastasis, improvement in local control remains an important goal. Until proven otherwise, the treatment of choice for the majority of patients still remains a conventional palliative course of 3.0 Gy × 10 fractions.

In research conducted over the past 20 years, we have observed abnormal trace-metal concentrations, including elevated serum copper and depressed plasma zinc, in blood samples collected from violence-prone individuals. The purpose of the study reported here was to test the validity of our observation that assaultive young males have elevated blood copper/zinc (Cu/Zn) ratios when compared to a control group of young males with no history of assaultive behavior. All male patients between the ages of 3 years and 20 years who made a first visit to the outpatient Pfeiffer Treatment Center in Naperville, Ill., during a two-month period were evaluated. Based on interviews with patients and their families and application of a standardized behavior scale, 135 assaultive young males and 18 controls with no history of assaultive behavior were identified. Blood samples were collected from test subjects and controls and analyzed for serum copper and plasma zinc concentrations by an independent laboratory using atomic absorption methods. The median Cu/Zn ratio for the assaultive subjects was 1.40 compared to 1.02 for controls, a statistically significant difference (t = 5.94; p < 0.01).