East-West Dialogues on the Ethics of Sex Robots.

The purpose of this essay is to review and evaluate chapters in Fan and Cherry's Sex Robots: Social Impact and the Future of Human Relations. In this edited volume, the authors of the various chapters present dialogues from the East and West to explore the social and cultural implications of sex robots. They also discuss whether sex robots have a positive, negative, or neutral impact on society and human relationships. This essay examines the key ideas presented in the book's chapters, evaluates their arguments, and identifies research directions for the ethics of sex robots in the future. Specifically, this essay provides a detailed analysis of certain schools of thought, including the capability approach, Confucianism and Daoism, and their relevance to the topic of sex robots.

Positive associations matter: Microbial relationships drive tick microbiome composition.

Untangling how factors such as environment, host, associations among bacterial species and dispersal predict microbial composition is a fundamental challenge. In this study, we use complementary machine-learning approaches to quantify the relative role of these factors in shaping microbiome variation of the blacklegged tick Ixodes scapularis. I. scapularis is the most important vector for Borrelia burgdorferi (the causative agent for Lyme disease) in the U.S. as well as a range of other important zoonotic pathogens. Yet the relative role of the interactions between pathogens and symbionts compared to other ecological forces is unknown. We found that positive associations between microbes where the occurrence of one microbe increases the probability of observing another, including between both pathogens and symbionts, was by far the most important factor shaping the tick microbiome. Microclimate and host factors played an important role for a subset of the tick microbiome including Borrelia (Borreliella) and Ralstonia, but for the majority of microbes, environmental and host variables were poor predictors at a regional scale. This study provides new hypotheses on how pathogens and symbionts might interact within tick species, as well as valuable predictions for how some taxa may respond to changing climate.

Clinical severity of COVID-19 with omicron variant predominance in relation to vaccination status, age, comorbidities- a single center in Selangor, Malaysia.

INTRODUCTION: Recently, the rapid surge of reported COVID-19 cases attributed to the Omicron variant of severe acute respiratory syndrome coronavirus (SARS-CoV-2) created an immediate concern across nations. Local information pertaining to the new variant of concern (VOC) is lacking. We aimed to determine the clinical characteristics of COVID-19 during a period of Omicron prevalence among patients hospitalised from February 1 to 21, 2022 at Sungai Buloh Hospital and to estimate the risks of disease progression presumably caused by this variant in association with gender, age, comorbidity, and vaccination status. MATERIALS AND METHODS: In this retrospective, singlecentered, retrospective cohort study, all hospitalised adults with laboratory-confirmed COVID-19, aged 18 and above, were recruited from February 1 to 21, 2022. Clinical characteristics, investigations, and outcomes were assessed. RESULTS: A total of 2279 patients aged 18 years and above with laboratory-proven COVID-19 were recruited and analysed, excluding 32 patients owing to incomplete data. Majority of the study population had a mean age of 41.8 ± 17.7, was female-predominant (1329/2279, 58.6%), had completed a primary series of vaccination with a booster (1103/2279, 48.4%), and had no underlying medical conditions (1529/2279, 67.4%). The risk of COVID-19-related disease progression was significantly lower in hospitalised patients under the age of 50 who were female, had no comorbidity, and had completed two doses of the primary series with or without a booster. [respectively, OR 7.94 (95% CI 6.16, 10.23); 1.68 (1.34, 2,12); 2.44 (1.85, 3.22); 2.56 (1.65, 3.97), p< 0.001]. CONCLUSION: During the period of Omicron prevalence, a favourable outcome of COVID-19 was strongly associated with female gender, age below 50, a comorbidity-free condition, and having completed immunization. With this new observation, it could help improve public health planning and clinical management in response to the emergence of the latest VOC.

A quality improvement project: Reducing bloodstream infection by improving adherence to the care bundle of peripheral vascular catheters at the COVID-19 treatment centre.

INTRODUCTION: During the COVID-19 pandemic, bloodstream infection (BSI) rates were substantially rising in Sungai Buloh Hospital (HSB). It is believed that the COVID-19 pandemic has had an adverse impact on BSI incidence caused by contaminated periphery vascular catheters (PVCs). The study's objective is to reduce the BSI rates in HSB by improving adherence to the PVC care bundle via the Plan-Do-Study-Act (PDSA) approach. MATERIALS AND METHODS: A quality improvement (QI) project was employed over four months, from June to September 2021, during the COVID-19 pandemic in HSB. All adults hospitalised for COVID-19 with intravenous lines were subjected to data collection. A baseline audit was conducted to study BSI incidence from April to May 2021. Implementation was carried out by PDSA cycles and data on BSI rates per 100 admissions was described using a monthly run chart. RESULTS: At baseline, the BSI rate per 100 admissions was 5.44 before implementing our QI project. Initial changes via PDSA cycles did not bring significant improvements to BSI rates and a rising trend in BSI rates was observed after two PDSA cycles. Further audits identified the problem of noncompliance with the practice of aseptic non-touch technique (ANTT) and a lack of effective leadership in implementing the PVC care bundle. The third PDSA cycle focused on adopting practical leadership skills among senior clinicians to ensure compliance with the prevention bundle and to encourage the use of ultrasound guidance for difficult line insertion. After the third PDSA cycle, the BSI rate per 100 admissions was reduced from 6.41 to 4.34 (p < 0.05). The BSI rates continued to decline down the line for another five months. CONCLUSION: Through QI initiatives, the risk of BSI can be significantly reduced.

Novel types of frequency filtering in the lateral perforant path projections to dentate gyrus.

Despite its evident importance to learning theory and models, the manner in which the lateral perforant path (LPP) transforms signals from entorhinal cortex to hippocampus is not well understood. The present studies measured synaptic responses in the dentate gyrus (DG) of adult mouse hippocampal slices during different patterns of LPP stimulation. Theta (5 Hz) stimulation produced a modest within-train facilitation that was markedly enhanced at the level of DG output. Gamma (50 Hz) activation resulted in a singular pattern with initial synaptic facilitation being followed by a progressively greater depression. DG output was absent after only two pulses. Reducing release probability with low extracellular calcium instated frequency facilitation to gamma stimulation while long-term potentiation, which increases release by LPP terminals, enhanced within-train depression. Relatedly, per terminal concentrations of VGLUT2, a vesicular glutamate transporter associated with high release probability, were much greater in the LPP than in CA3-CA1 connections. Attempts to circumvent the potent gamma filter using a series of short (three-pulse) 50 Hz trains spaced by 200 ms were only partially successful: composite responses were substantially reduced after the first burst, an effect opposite to that recorded in field CA1. The interaction between bursts was surprisingly persistent (>1.0 s). Low calcium improved throughput during theta/gamma activation but buffering of postsynaptic calcium did not. In all, presynaptic specializations relating to release probability produce an unusual but potent type of frequency filtering in the LPP. Patterned burst input engages a different type of filter with substrates that are also likely to be located presynaptically. KEY POINTS: The lateral perforant path (LPP)-dentate gyrus (DG) synapse operates as a low-pass filter, where responses to a train of 50 Hz, γ frequency activation are greatly suppressed. Activation with brief bursts of γ frequency information engages a secondary filter that persists for prolonged periods (lasting seconds). Both forms of LPP frequency filtering are influenced by presynaptic, as opposed to postsynaptic, processes; this contrasts with other hippocampal synapses. LPP frequency filtering is modified by the unique presynaptic long-term potentiation at this synapse. Computational simulations indicate that presynaptic factors associated with release probability and vesicle recycling may underlie the potent LPP-DG frequency filtering.

Growth Dynamics and Antibiotic Elimination of Symbiotic Rickettsia buchneri in the Tick Ixodes scapularis (Acari: Ixodidae).

Rickettsia buchneri is the principal symbiotic bacterium of the medically significant tick Ixodes scapularis This species has been detected primarily in the ovaries of adult female ticks and is vertically transmitted, but its tissue tropism in other life stages and function with regard to tick physiology is unknown. In order to determine the function of R. buchneri, it may be necessary to produce ticks free from this symbiont. We quantified the growth dynamics of R. buchneri naturally occurring in I. scapularis ticks throughout their life cycle and compared it with bacterial growth in ticks in which symbiont numbers were experimentally reduced or eliminated. To eliminate the bacteria, we exposed ticks to antibiotics through injection and artificial membrane feeding. Both injection and membrane feeding of the antibiotic ciprofloxacin were effective at eliminating R. buchneri from most offspring of exposed females. Because of its effectiveness and ease of use, we have determined that injection of ciprofloxacin into engorged female ticks is an efficient means of clearing R. buchneri from the majority of progeny.IMPORTANCE This paper describes the growth of symbiotic Rickettsia buchneri within Ixodes scapularis through the life cycle of the tick and provides methods to eliminate R. buchneri from I. scapularis ticks.

Enhanced Interrogation, Consequential Evaluation, and Human Rights to Health.

Balfe argues against enhanced interrogation. He particularly focuses on the involvement of U.S. healthcare professionals in enhanced interrogation. He identifies several empirical and normative factors and argues that they are not good reasons to morally justify enhanced interrogation. I argue that his argument can be improved by making two points. First, Balfe considers the reasoning of those healthcare professionals as utilitarian. However, careful consideration of their ideas reveals that their reasoning is consequential rather than utilitarian evaluation. Second, torture is a serious human rights abuse. When healthcare professionals become involved in enhanced interrogation, they violate not only human rights against torture but also human rights to health. Considering the consequential reasoning against human rights abuses, healthcare professionals' involvement in enhanced interrogation is not morally justified. Supplementing Balfe's position with these two points makes his argument more complete and convincing, and hence it can contribute to the way which shows that enhanced interrogation is not justified by consequential evaluation.

Evaluating Disability Insurance Assistance as a Specific Intervention by Physiatrists at a Cancer Center.

Because of their expertise, physiatrists provide disability insurance assistance for cancer survivors. In this brief report, we perform a descriptive retrospective analysis of all new (354) outpatient physiatry consultations from January 1, 2009, to December 31, 2013, at a National Cancer Institute Comprehensive Cancer Center. Disability and/or work accommodations were brought up at some point with the physiatrist during the duration of their care for 131 (37%) of 354 patients. More than 90% of the discussions took place during the first visit. Of those patients who had a documented disability/employment discussion, 58 (44.3%) of 131 patients were originally referred for disability assistance specifically, and 58 (44.3%) of 131 also had disability insurance paperwork completed by the physiatrist. Outcomes of initial physiatry disability insurance assistance were 45 (77.6%) of 58 approved/renewed, 5 (8.6%) of 58 denied, and 8 (13.8%) of 58 unknown/died during the disability application process. The median form size was 33 (SD, 25.95) items. This study is the first of its kind and provides an initial look at work-related discussions and support with disability insurance paperwork as a specific intervention provided by physiatrists at a cancer center. The results are compelling and demonstrate that physiatrists frequently provide these interventions. These interventions take considerable time and effort but are generally successful.

Girl Talk: A Smartphone Application to Teach Sexual Health Education to Adolescent Girls.

STUDY OBJECTIVE: Produce Girl Talk, a free smartphone application containing comprehensive sexual health information, and determine the application's desirability and appeal among teenage girls. DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS: Thirty-nine girls ages 12 to 17 years from Rhode Island participated in a 2-phase prospective study. In phase I, 22 girls assessed a sexual health questionnaire in focus groups. In phase II, 17 girls with iPhones used Girl Talk for 2 weeks and answered the revised sexual health questionnaire and interview questions before and after use. MAIN OUTCOME MEASURES: Participants' responses to the sexual health questionnaire, interviews, and time viewing the application were used to determine feasibility and desirability of Girl Talk. RESULTS: Girl Talk was used on average for 48 minutes during participants' free time on weekends for 10- to 15-minute intervals. Reported usefulness of Girl Talk as a sexual health application from baseline (6 participants) to follow-up (16 participants) increased significantly (35.3% vs 94.1%; P < .001). Knowledge improved most in topics related to anatomy and physiology (70.5% to 74.7% out of 7 questions), sexuality and relationships (76.5% to 80.0% out of 10 questions), and STI prevention (75.6% to 79.0% out of 7 questions). Most phase II participants (13 out of 17, or 76.5%) were exposed to sexual health education before using Girl Talk, but 16 out of 17 participants (94.1%) stated that the application provided new and/or more detailed information than health classes. CONCLUSION: Girl Talk can potentially connect teenage girls to more information about sexual health vs traditional methods, and participants recommended the application as a valuable resource to learn about comprehensive sexual health.

Paediatric cerebral sinovenous thrombosis: findings of the International Paediatric Stroke Study.

OBJECTIVES: We evaluated clinical features, treatment practices and early outcome in a multicentre cohort of children with cerebral sinovenous thrombosis (CSVT). METHODS: Children with CSVT from 10 countries were enrolled from January 2003 to July 2007 in the International Paediatric Stroke Study. We analysed clinical symptoms, underlying conditions, antithrombotic treatment and neurological outcome at hospital discharge in 170 children. RESULTS: Of 170 children enrolled, 60% were male; median age 7.2 years (IQR 2.9-12.4). Headache, altered consciousness, focal deficits and seizures were common presenting clinical features. Infarction affected 37% and intracranial haemorrhage 31%. Risk factors included chronic disease in 50%; acute systemic illness or head/neck disorders 41%; prothrombotic state 20% and other haematological abnormality 19%. Discharge neurological status was normal in 48%, abnormal in 43% and unknown in 5%. Antithrombotic therapy was common, most often low molecular weight heparin was common, with significant regional variation in treatment practices. Mortality was low (4%) and was associated with no anticoagulation but not underlying chronic disease, anatomic extent of thrombosis or intracranial haemorrhage. Abnormal neurological status at discharge or death was associated with decreased level of consciousness at presentation and the presence of an identified prothrombotic state. CONCLUSIONS: Our study extends the observations of previously published smaller studies in children with CSVT that this is a morbid disease with diverse underlying causes and risk factors. Divergent treatment practices among highly specialised centres as well as limited data on treatment efficacy and safety suggest that further study of this condition is warranted.

Disaggregating activities of daily living limitations for predicting nursing home admission.

OBJECTIVE: To examine whether disaggregated activities of daily living (ADL) limitations better predict the risk of nursing home admission compared to conventionally used ADL disability counts. DATA SOURCES: We used panel data from the Health and Retirement Study (HRS) for years 1998-2010. The HRS is a nationally representative survey of adults older than 50 years (n = 18,801). STUDY DESIGN: We fitted Cox regressions in a continuous time survival model with age at first nursing home admission as the outcome. Time-varying ADL disability types were the key explanatory variables. PRINCIPAL FINDINGS: Of the six ADL limitations, bathing difficulty emerged as the strongest predictor of subsequent nursing home placement across cohorts. Eating and dressing limitations were also influential in driving admissions among more recent cohorts. Using simple ADL counts for analysis yielded similar adjusted R(2) s; however, the amount of explained variance doubled when we allowed the ADL disability measures to time-vary rather than remain static. CONCLUSIONS: Looking beyond simple ADL counts can provide health professionals insights into which specific disability types trigger long-term nursing home use. Functional disabilities measured closer in time carry more prognostic power than static measures.

Inpatient rehabilitation performance of patients with paraneoplastic cerebellar degeneration.

OBJECTIVE: To evaluate the functional improvement of rehabilitation inpatients with paraneoplastic cerebellar degeneration. DESIGN: Retrospective review. SETTING: Referral-based hospitals. PARTICIPANTS: Cancer rehabilitation inpatients (N=7) admitted to 3 different cancer centers with a diagnosis of paraneoplastic cerebellar degeneration. INTERVENTION: Medical records were retrospectively analyzed for demographic, laboratory, medical, and functional data. MAIN OUTCOME MEASURE: FIM. RESULTS: All 7 patients were white women (median age, 62y). Primary cancers included ovarian carcinoma (n=2), small cell lung cancer (n=2), uterine carcinoma (n=2), and invasive ductal breast carcinoma (n=1). Mean admission total FIM score was 61±23.97. Mean discharge total FIM score was 73.6±29.35. The mean change in total FIM score was 12.6 (P=.0018). The mean length of rehabilitation stay was 17.1 days. The mean total FIM efficiency was .73. Of the 7 patients, 5 (71%) were discharged home, 1 (14%) was discharged to a nursing home, and 1 (14%) was transferred to the primary acute care service. CONCLUSIONS: To our knowledge, this is the first study to demonstrate the functional performance of a group of rehabilitation inpatients with paraneoplastic cerebellar degeneration. Despite the poor neurologic prognosis associated with this syndrome, these patients made significant functional improvements in inpatient rehabilitation. When appropriate, inpatient rehabilitation should be considered. Further studies with larger sample sizes are needed.

Goal setting for health behavior change: evidence from an obesity intervention for rural low-income women.

INTRODUCTION: Rural, minority populations are disproportionately affected by overweight and obesity and may benefit from lifestyle modification programs that are tailored to meet their unique needs. Obesity interventions commonly use goal setting as a behavior change strategy; however, few have investigated the specific contribution of goal setting to behavior change and/or identified the mechanisms by which goal setting may have an impact on behavior change. Furthermore, studies have not examined goal setting processes among racial/ethnic minorities. Using data from an obesity intervention for predominately minority women in rural North Carolina, this study sought to examine whether intervention participation resulted in working on goals and using goal setting strategies which in turn affected health behavior outcomes. It also examined racial/ethnic group differences in working on goals and use of goal setting strategies. METHODS: Data came from a community-based participatory research project to address obesity among low-income, predominately minority women in rural North Carolina. A quasi-experimental intervention design was used. Participants included 485 women aged 18 years and over. Intervention participants (n=208) received health information and goal setting support through group meetings and tailored newsletters. Comparison participants (n = 277) received newsletters on topics unrelated to obesity. Surveys assessed physical activity, fruit and vegetable intake, goal-related stage of change, and use of goal setting strategies. Chi squared statistics were used to assess intervention group differences in changes in goal-related stage of change and use of goal setting strategies as well as racial/ethnic group differences in stage of change and use of goal setting strategies at baseline. The causal steps approach of Baron and Kenny was used to assess mediation. RESULTS: Intervention compared to comparison participants were more likely to move from contemplation to action/maintenance for the goals of improving diet (58% intervention, 44% comparison, p= 0.04) and physical activity (56% intervention, 31% comparison, p ≤ 0.0001). Intervention group differences were not found for moving from precontemplation to a higher category. At baseline, black compared to white participants were more likely to be working on the goals of getting a better education (p < 0.0001), owning a home (p < 0.01), starting a business (p < 0.0001), and improving job skills (p <0.05). For whites only, intervention participants were more likely than comparison participants to move from contemplation to action/maintenance for the goal of improving diet ( p< 0.05). For both blacks (p < 0.05) and whites (p < 0.0001), intervention participants were more likely than comparison participants to move from contemplation to action/maintenance for the goal of increasing physical activity. For all participants, progression in stages of change mediated the intervention effect on physical activity, but not fruit and vegetable intake. The intervention did not reveal an impact on use of goal setting strategies. CONCLUSIONS: In this sample of low-income, rural women, the intervention's goal setting component influenced behavior change for participants who were contemplating lifestyle changes at baseline. Racial/ethnic group differences in goal setting indicate the need to gain greater understanding of individual, social, and environmental factors that may uniquely have an impact on goal setting, and the importance of tailoring obesity intervention strategies for optimal, sustainable behavior change.

Pathology of runting in farmed saltwater crocodiles (Crocodylus porosus) in Australia.

Extremely poor growth of some individuals within a birth cohort (runting) is a significant problem in crocodile farming. We conducted a pathological investigation to determine if infectious disease is associated with runting in farmed saltwater crocodiles (Crocodylus porosus) and to look for evidence of other etiologies. In each of 2005 and 2007, 10 normal and 10 runt crocodiles, with an average age of 5.5 months and reared under identical conditions, were sampled. Laboratory testing included postmortem; histological examination of a wide variety of tissues (with quantitation of features that were noted subjectively to be different between groups); hematology; serum biochemistry (total protein, albumin, globulins, total calcium, phosphorus, and iron); bacterial culture of liver and spleen (2005 only); viral culture of liver, thymus, tonsil, and spleen using primary crocodile cell lines (2007 only); and serum corticosterone (2007 only). The only evidence of infectious disease was mild cutaneous poxvirus infection in 45% of normal and 40% of runt crocodiles and rare intestinal coccidia in 5% of normal and 15% of runt crocodiles. Bacterial and viral culture did not reveal significant differences between the 2 groups. However, runt crocodiles exhibited significant (P < .05) increases in adrenocortical cell cytoplasmic vacuolation and serum corticosterone, decreased production of bone (osteoporosis), and reduced lymphoid populations in the spleen, tonsil, and thymus. Runts also exhibited moderate anemia, hypoalbuminemia, and mild hypophosphatemia. Taken together, these findings suggest an association between runting and a chronic stress response (hyperactivity of the hypothalamic-pituitary-adrenal axis).

Predictors of disease severity in patients admitted to a cholera treatment center in urban Haiti.

Cholera, previously unrecognized in Haiti, spread through the country in the fall of 2010. An analysis was performed to understand the epidemiological characteristics, clinical management, and risk factors for disease severity in a population seen at the GHESKIO Cholera Treatment Center in Port-au-Prince. A comprehensive review of the medical records of patients admitted during the period of October 28, 2010-July 10, 2011 was conducted. Disease severity on admission was directly correlated with older age, more prolonged length of stay, and presentation during the two epidemic waves seen in the observation period. Although there was a high seroprevalence of human immunodeficiency virus (HIV), severity of cholera was not greater with HIV infection. This study documents the correlation of cholera waves with rainfall and its reduction in settings with improved sanitary conditions and potable water when newly introduced cholera affects all ages equally so that interventions must be directed throughout the population.

SU-E-T-26: Evaluation of New Pre-Treatment In-Air Patient Specific QA Software for TomoTherapy Treatments.

PURPOSE: Math Resolutions, LLC, has extended their Dosimetry Check quality assurance software to include TomoTherapy treatments. Data collected from TomoTherapy's MVCT detectors is processed and compared to the planned treatment dose allowing for pre-treatment QA without the use of phantoms and other detectors. This study presents an overview of our experience at the University of Virginia developing, implementing, and verifying this novel QA strategy. METHODS: Low modulation and high modulation cheese phantom plans as well as patient plans (prostate, GYN, and vertebra) were used to test the Dosimetry Check in-air software. For all evaluations the treatment table was removed from the XML file of each plan using software provided by Accuray and the resulting in-air calibration plan was delivered. The exit detector sinogram was extracted from the machine and imported into Dosimetry Check along with the TomoTherapy calculated planned dose. The fluence maps were reconstructed and used to recalculate the dose. RESULTS: The percent difference between the planned dose and the dose calculated from the exit detectors by Dosimetry Check ranged between 0.62% for a simple low modulation cheese phantom plan with a cylindrical target to 7.3% for a high modulation 2.5cm prostate plan. The gamma indices reported range from 94.7% to 97.8% <1 over the overall calculation area for the plans tested using a gamma of 3% and 3mm. For the area receiving over 80% of the prescribed dose, the gamma ranged from 80.7% to 92.9% <1. CONCLUSIONS: The results of our investigation of Math Resolutions' new product in development, Dosimetry Check's pre-treatment in-air QA software, demonstrate that it has the potential be a very useful and practical tool for TomoTherapy QA. Further testing is being performed in which various errors are intentionally introduced in the delivered dose to test the limits of Dosimetry Check's sensitivity. Research Grant from Math Resolutions LLC 01/12/2012-01/11/2013 Math Resolutions’ Dosimetry Check software was given to UVa to assist with evaluating the precision of the product in reconstructing dose from the TomoTherapy exit detector data.

SU-E-T-23: TomoTherapy Patient QA Using Exit Detector Measurement of Pre-Treatment In-Air Delivery.

PURPOSE: Currently, the recommended TomoTherapy patient specific QA involves setting up a DQA procedure and delivering it to a phantom with an ion chamber and film measurement. The process is time-consuming and the DQA result is susceptible to errors in phantom setup. Our study explores the feasibility of using TomoTherapy's intrinsic exit detectors to perform patient specific QA by measuring the fluence received by the detectors during pre-treatment in-air delivery for our STAT-RAD workflow. METHODS: A TomoTherapy patient plan is converted into a calibration procedure in which the couch remains out of the gantry. The signal measured by the exit detector is exported through manufactory provided software. In-house developed software is used to reconstruct exit detector signal from the dicom-exported delivery plan. The software relies on individual leaf profiles as well as tongue-and-groove profiles of each adjacent leaf-pair extracted from an in-house developed calibration procedure. The difference between the reconstructed and measured detector signal can be analyzed by a simple algorithm which has been developed to estimate the dose difference of any given point inside a patient or phantom. Several patient plans have been tested with this in-air delivery QA method. In some of the tested plans, errors have been introduced to assure the estimated point dose error agrees with the ion chamber measurement in a phantom. RESULTS: The in-house exit detector reconstruction software has been validated to be able to reconstruct the exit detector signal with errors <1%. The software estimated point dose agrees within 3% to the ion chamber measurement. CONCLUSIONS: Our study shows that it is feasible and efficient to perform patient specific QA using the exit detector signal recorded during the in-air pretreatment delivery. This approach is easy to perform and it is faster than conventional QA approach.

SU-E-J-192: Static Breath-Hold MRI Based Measurement of Change in Pulmonary Function Following a Course of Radiation Therapy.

PURPOSE: Radiation Therapy (RT) induced pulmonary function change may depend on the location, underlying function of that lung prior to radiations, radiation dose/fractionation and other factors. We propose to evaluate the radiation induced pulmonary function change using static breath-hold MRI scans with vascular information and 3D deformable image registration which can provide pulmonary function relative to RT dose on a regional basis. METHODS: A MRI scan pair near the end of inhale and near the end of exhale with breath hold were acquired for one lung cancer patient before RT and 6 months after RT. The patient was treated with SBRT with 55 Gy to PTVs in the right and the left lung respectively. B-spline based vesselness preserving image registration algorithm was applied to register the MRI pair for the calculation of local lung expansion as a measurement of regional pulmonary function (PF). The PF maps before RT and after RT were then mapped to the planning CT using the same algorithm tuned for MRI-CT registration. The pulmonary function change was calculated via the PF ratio between two MRI pairs. RESULTS: Strong spatial correlation was found between the irradiated lung region and the region with greatly decreased PF. Based on dose and PFC distribution, no strong determinant factor was found for PF lost in the left lung while the right lung shows that all the lung tissue receiving dose larger than 28 Gy will have a decreased PF. CONCLUSIONS: We demonstrated a method that uses static breath-hold MRI based lung imaging to evaluate radiation induced pulmonary function change which can be applied to study the dose and the pulmonary function change in a regional basis. This work is supported by NIH grant support 1R21CA144063.