keyword
MENU ▼
Read by QxMD icon Read
search

Chetty

keyword
https://www.readbyqxmd.com/read/28209558/readiness-for-delivering-digital-health-at-scale-lessons-from-a-longitudinal-qualitative-evaluation-of-a-national-digital-health-innovation-program-in-the-united-kingdom
#1
Marilyn R Lennon, Matt-Mouley Bouamrane, Alison M Devlin, Siobhan O'Connor, Catherine O'Donnell, Ula Chetty, Ruth Agbakoba, Annemieke Bikker, Eleanor Grieve, Tracy Finch, Nicholas Watson, Sally Wyke, Frances S Mair
BACKGROUND: Digital health has the potential to support care delivery for chronic illness. Despite positive evidence from localized implementations, new technologies have proven slow to become accepted, integrated, and routinized at scale. OBJECTIVE: The aim of our study was to examine barriers and facilitators to implementation of digital health at scale through the evaluation of a £37m national digital health program: ‟Delivering Assisted Living Lifestyles at Scale" (dallas) from 2012-2015...
February 16, 2017: Journal of Medical Internet Research
https://www.readbyqxmd.com/read/28207935/false-negative-fetal-cell-free-dna-screening-for-microdeletion-syndromes-in-the-presence-of-an-unbalanced-translocation-involving-monosomy-4p
#2
Zhongxia Qi, Shreshtha Madaan, Shilpa Chetty, Jingwei Yu, Arun P Wiita
No abstract text is available yet for this article.
February 16, 2017: Prenatal Diagnosis
https://www.readbyqxmd.com/read/28195664/an-adaptive-model-for-rapid-and-direct-estimation-of-extravascular-extracellular-space-in-dynamic-contrast-enhanced-mri-studies
#3
Azimeh N V Dehkordi, Alireza Kamali-Asl, James R Ewing, Ning Wen, Indrin J Chetty, Hassan Bagher-Ebadian
Extravascular extracellular space (ve ) is a key parameter to characterize the tissue of cerebral tumors. This study introduces an artificial neural network (ANN) as a fast, direct, and accurate estimator of ve from a time trace of the longitudinal relaxation rate, ΔR1 (R1  = 1/T1 ), in DCE-MRI studies. Using the extended Tofts equation, a set of ΔR1 profiles was simulated in the presence of eight different signal to noise ratios. A set of gain- and noise-insensitive features was generated from the simulated ΔR1 profiles and used as the ANN training set...
February 14, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28119348/a-pragmatic-approach-to-vasculitis-in-the-gastrointestinal-tract
#4
REVIEW
Runjan Chetty, Stefano Serra
Although vasculitis involving the gastrointestinal tract (GIT) is an uncommon occurrence, occasionally vasculitis can present as haemorrhagic infarction or ischaemia for which a length of bowel is removed. Invariably, the appropriate clinical history is not forthcoming, or vasculitis is not clinically suspected. The purpose of this overview is to provide the practising gastrointestinal (GI) pathologist with a framework to recognise and diagnose vasculitides within the GIT. The classification may be approached by aetiological agent or size of vessel involved; an international consensus group now favours the latter approach...
January 24, 2017: Journal of Clinical Pathology
https://www.readbyqxmd.com/read/28096372/helical-structure-stability-and-dynamics-in-human-apolipoprotein-e3-and-e4-by-hydrogen-exchange-and-mass-spectrometry
#5
Palaniappan S Chetty, Leland Mayne, Sissel Lund-Katz, S Walter Englander, Michael C Phillips
Apolipoprotein E (apoE) plays a critical role in cholesterol transport in both peripheral circulation and brain. Human apoE is a polymorphic 299-residue protein in which the less common E4 isoform differs from the major E3 isoform only by a C112R substitution. ApoE4 interacts with lipoprotein particles and with the amyloid-β peptide, and it is associated with increased incidence of cardiovascular and Alzheimer's disease. To understand the structural basis for the differences between apoE3 and E4 functionality, we used hydrogen-deuterium exchange coupled with a fragment separation method and mass spectrometric analysis to compare their secondary structures at near amino acid resolution...
January 31, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28072395/evaluation-of-adaptive-treatment-planning-for-patients-with-non-small-cell-lung-cancer
#6
Hualiang Zhong, Salim Siddiqui, Benjamin Movsas, Indrin Chetty
The purpose of this study was to develop metrics to evaluate uncertainties in deformable dose accumulation (DDA) for patients with non-small cell lung cancer (NSCLC). Initial treatment plans (primary) and cone-beam CT (CBCT) images were retrospectively processed for seven NSCLC patients, who showed significant tumor regression during the course of treatment. Each plan was developed with IMRT for 2 Gy��33 fractions. A B-spline-based DIR algorithm was used to register weekly CBCT images to a reference image acquired at fraction 21 and the resultant displacement vector fields (DVFs) were then modified using a finite element method (FEM)...
January 10, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28068232/analysis-of-the-factors-contributing-to-vertebral-compression-fractures-after-spine-stereotactic-radiosurgery
#7
David Boyce-Fappiano, Erinma Elibe, Lonni Schultz, Samuel Ryu, M Salim Siddiqui, Indrin Chetty, Ian Lee, Jack Rock, Benjamin Movsas, Farzan Siddiqui
PURPOSE: To determine our institutional vertebral compression fracture (VCF) rate after spine stereotactic radiosurgery (SRS) and determine contributory factors. METHODS AND MATERIALS: Retrospective analysis from 2001 to 2013 at a single institution was performed. With institutional review board approval, electronic medical records of 1905 vertebral bodies from 791 patients who were treated with SRS for the management of primary or metastatic spinal lesions were reviewed...
February 1, 2017: International Journal of Radiation Oncology, Biology, Physics
https://www.readbyqxmd.com/read/28048749/su-f-r-49-a-novel-kinetic-model-for-prediction-of-tumor-local-control-for-patients-with-lung-cancer
#8
H Zhong, S Siddiqui, B Zhao, H Li, K Barton, F Siddiqui, B Movsas, I Chetty
PURPOSE: Modeling tumor control probability (TCP) can help optimize treatment plans for better treatment outcomes. This study sought to quantify the radiobiological parameters of the TCP model for patients with lung cancer. METHODS: A two-compartment kinetic model was developed to model tumor regression for five NSCLC patients. The model has three parameters: cell survival fraction, dead-cell-resolving time and tumor doubling time. The last one was extended to a function of tumor volume...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048563/we-ab-207b-05-correlation-of-normal-lung-density-changes-with-dose-after-stereotactic-body-radiotherapy-sbrt-for-early-stage-lung-cancer
#9
Q Wu, S Devpura, K Feghali, C Liu, M Ajlouni, B Movsas, I Chetty
PURPOSE: To investigate correlation of normal lung CT density changes with dose accuracy and outcome after SBRT for patients with early stage lung cancer. METHODS: Dose distributions for patients originally planned and treated using a 1-D pencil beam-based (PB-1D) dose algorithm were retrospectively recomputed using algorithms: 3-D pencil beam (PB-3D), and model-based METHODS: AAA, Acuros XB (AXB), and Monte Carlo (MC). Prescription dose was 12 Gy × 4 fractions...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048506/we-ab-207b-12-prospective-study-of-the-relationship-between-dose-volume-clinical-toxicity-and-patient-reported-outcomes-in-lung-cancer-patients-treated-with-sbrt
#10
E Mayyas, S Vance, S Brown, J Liu, J Kim, S Zhen, S Devpura, M Ajlouni, S Salim, I Chetty, B Movsas
PURPOSE: To determine in a prospective study, the correlation between radiation dose/volume, clinical toxicities and patient-reported, quality of life (QOL) resulting from lung SBRT. METHODS: For 106 non-small cell lung cancer (NSCLC) patients receiving SBRT (12 Gy × 4), symptoms including cough, dyspnea, fatigue and pneumonitis were measured at baseline (before treatment), after treatment and 3, 6, and 12 months post-treatment. Toxicity was graded from zero to five...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048467/su-g-jep2-08-image-guided-radiation-therapy-using-synthetic-cts-in-brain-cancer
#11
R G Price, J Kim, W Zheng, I J Chetty, C Glide-Hurst
PURPOSE: Synthetic-CTs(synCTs) are essential for MR-only treatment planning. However, the performance of synCT for IGRT must be carefully assessed. This work evaluated the accuracy of synCT and synCT-generated DRRs and determined their performance for IGRT in brain cancer radiation therapy. METHODS: MR-SIM and CT-SIM images were acquired of a novel anthropomorphic phantom and a cohort of 12 patients. SynCTs were generated by combining an ultra-short echo time (UTE) sequence with other MRI datasets using voxel-based weighted summation...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048441/su-f-t-506-development-and-commissioning-of-the-effective-and-efficient-grid-therapy-using-high-dose-rate-flattening-filter-free-beam-and-multileaf-collimator
#12
M Liu, N Wen, C Beyer, F Siddiqui, I Chetty, B Zhao
PURPOSE: Treating bulky tumors with grid therapy (GT) has demonstrated high response rates. Long delivery time (∼15min), with consequent increased risk of intrafraction motion, is a major disadvantage of conventional MLC-based GT (MLC-GT). The goal of this study was to develop and commission a MLC-GT technique with similar dosimetric characteristics, but more efficient delivery. METHODS: Grid plan was designed with 10X-FFF (2400MU/min) beam and MLC in a commercial treatment planning system (TPS)...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048385/su-g-brc-07-evaluation-of-aaa-focal-spot-size-for-srs-planning-using-end-to-end-dosimetric-data
#13
S Gardner, A Doemer, B Miller, N Wen, I Chetty
PURPOSE: To use end-to-end dosimetric measurements with Gafchromic film to evaluate the effects of focal spot size parameter for small-field dose calculations using AAA for SRS lesions. METHODS: A total of 13 plans, corresponding to 7 patients previously treated with cranial SRS, were analyzed in this study (target volume range:[0.67cc,13.9cc]). The plans included DCA delivery (4 plans total) and VMAT delivery (9 plans total). All plans were mapped to a solid water phantom (15 cm thickness; isocenter and film plane at 7...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048314/su-d-204-07-retrospective-correlation-of-dose-accuracy-with-regions-of-local-failure-for-early-stage-lung-cancer-patients-treated-with-stereotactic-body-radiotherapy
#14
S Devpura, H Li, C Liu, C Fraser, M Ajlouni, B Movsas, I Chetty
PURPOSE: To correlate dose distributions computed using six algorithms for recurrent early stage non-small cell lung cancer (NSCLC) patients treated with stereotactic body radiotherapy (SBRT), with outcome (local failure). METHODS: Of 270 NSCLC patients treated with 12Gyx4, 20 were found to have local recurrence prior to the 2-year time point. These patients were originally planned with 1-D pencil beam (1-D PB) algorithm. 4D imaging was performed to manage tumor motion...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048111/su-f-j-38-dose-rates-and-preliminary-evaluation-of-contouring-similarity-metrics-using-4d-cone-beam-ct
#15
A Santoso, K Song, Y Qin, S Gardner, C Liu, R Cattaneo, I Chetty, B Movsas, M Aljouni, N Wen
PURPOSE: 4D imaging modalities require detailed characterization for clinical optimization. The On-Board Imager mounted on the linear accelerator was used to investigate dose rates in a tissue mimicking phantom using 4D-CBCT and assess variability of contouring similarity metrics between 4D-CT and 4D-CBCT retrospective reconstructions. METHODS: A 125 kVp thoracic protocol was used. A phantom placed on a motion platform simulated a patient's breathing cycle. An ion chamber was affixed inside the phantom's tissue mimicking cavities (i...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047756/we-ab-207b-09-margin-reduction-for-planning-target-volume-ptv-in-patients-with-localized-prostate-cancer-impact-on-delivered-dose-and-quality-of-life
#16
A Kumarasiri, C Liu, S Brown, C Glide-Hurst, M Elshaikh, I Chetty, B Movsas
PURPOSE: To estimate the delivered (cumulative) dose to targets and organs at risk for localized prostate cancer patients treated with reduced PTV margins and to evaluate preliminary patient reported quality-of-life (QOL). METHODS: Under an IRB-approved protocol, 20 prostate cancer patients (including 11 control patients) were treated with reduced planning margins (5 mm uniform with 4 mm at prostate/rectum interface). Control patients had standard margin (10/6 mm)-based treatments...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047648/su-g-tep2-08-evaluation-of-plastic-scintillator-detector-for-small-field-stereotactic-patient-specific-quality-assurance
#17
Y Qin, S Gardner, Y Huang, J Kim, N Wen, I Chetty
PURPOSE: To evaluate the performance of a commercial plastic scintillator detector (PSD) for small-field stereotactic patient-specific quality assurance using flattening-filter-free (FFF) beams. METHODS: A total of ten spherical targets (volume range:[0.03cc-2cc]) were planned using Dynamic Conformal Arc(DCA-10 plans) and Volumetric Modulated Arc Therapy(VMAT-10 plans) techniques in Eclipse(AAA v.11, 1mm dose calculation grid size). Additionally, 15 previously-treated cranial and spine SRS plans were evaluated (6 DCA, 9 VMAT, volume range:[0...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047636/su-f-t-566-absolute-film-dosimetry-for-stereotactic-radiosurgery-and-stereotactic-body-radiotherapy-quality-assurance-using-gafchromic-ebt3-films
#18
N Wen, S Lu, Y Qin, Y Huang, B Zhao, C Liu, I Chetty
PURPOSE: To evaluate the dosimetric uncertainty associated with Gafchromic (EBT3) films and establish an absolute dosimetry protocol for Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT). METHODS: EBT3 films were irradiated at each of seven different dose levels between 1 and 15 Gy with open fields, and standard deviations of dose maps were calculated at each color channel for evaluation. A scanner non-uniform response correction map was built by registering and comparing film doses to the reference diode array-based dose map delivered with the same doses...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047603/su-f-t-555-accurate-stereotactic-cone-tmrs-converted-from-pdds-scanned-with-ray-trace
#19
H Li, H Zhong, Y Qin, K Snyder, I Chetty, N Wen
PURPOSE: To investigate whether the accuracy of TMRs for stereotactic cones converted from PDDs scanned with Ray Trace can be improved, when compared against the TMRs converted from the traditional PDDs. METHODS: Ray Trace measurement in Sun Nuclear 3D Scanner is for accurate scan of small field PDDs. The system detects the center of field at two depths, for example, at 3 and 20 cm in our study, and then performs scan along the line passing the two centers. With both Ray Trace and the traditional method, PDDs for conical cones of 4, 5, 7...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047440/su-f-j-68-deformable-dose-accumulation-for-voxel-based-dose-tracking-of-ptv-cold-spots-for-adaptive-radiotherapy-of-the-head-and-neck
#20
C Liu, I Chetty, W Mao, A Kumarasiri, H Zhong, S Brown, F Siddiqui
PURPOSE: To utilize deformable dose accumulation (DDA) to determine how cold spots within the PTV change over the course of fractionated head and neck (H&N) radiotherapy. METHODS: Voxel-based dose was tracked using a DDA platform. The DDA process consisted of B-spline-based deformable image registration (DIR) and dose accumulation between planning CT's and daily cone-beam CT's for 10 H&N cancer patients. Cold spots within the PTV (regions receiving less than the prescription, 70 Gy) were contoured on the cumulative dose distribution...
June 2016: Medical Physics
keyword
keyword
13091
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"