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1.
bioRxiv ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38712158

RESUMO

Japanese Encephalitis Virus (JEV) transmission in temperate Australia has underscored a critical need to characterise transmission pathways and identify probable hosts of infection within the country. This systematic review consolidates existing research on the vertebrate hosts of JEV that are known to exist in Australia. Specifically, we aim to identify probable species for JEV transmission, their potential role as either a spillover or maintenance host and identify critical knowledge gaps. Data were extracted from studies involving experimental infection, seroprevalence, and virus isolation and were available for 22 vertebrate species known to reside in Australia. A host competence score was calculated to assess the potential for a given species to infect JEV vectors and to quantity their possible role in JEV transmission. Based on the host competence score and ecology of each species, we find ardeid birds, feral pigs, and flying foxes have potential as maintenance hosts for JEV in the Australian context. We also note that brushtail possums and domestic pigs have potential as spillover hosts under certain outbreak conditions. However, evidence to confirm these roles in localized transmission or outbreaks is sparse, emphasizing the need for further targeted research. This review provides a foundation for future investigations into JEV transmission in Australia, advocating for enhanced surveillance and standardized research methodologies to better understand and mitigate the virus's impact.

2.
Biomed Mater Eng ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38758990

RESUMO

BACKGORUND: The development of vibration-induced finger disorders is likely associated with combined static and dynamic responses of the fingers to vibration exposure. To study the mechanism of the disorders, a new rat-tail model has been established to mimic the finger vibration and pressure exposures. However, the mechanical behavior of the tail during compression needs to be better understood to improve the model and its applications. OBJECTIVE: To investigate the static and time-dependent force responses of the rat tail during compression. METHODS: Compression tests were conducted on Sprague-Dawley cadaver rat tails using a micromechanical system at three deformation velocities and three deformation magnitudes. Contact-width and the time-histories of force and deformation were measured. Additionally, force-relaxation tests were conducted and a Prony series was used to model the force-relaxation behavior of the tail. RESULTS: The rat tails' force-deformation and stiffness-deformation relationships were strongly nonlinear and time-dependent. Force/stiffness increased with an increase in deformation and deformation velocity. The time-dependent force-relaxation characteristics of the tails can be well described using a Prony series. CONCULSIONS: We successfully quantified the static and time-dependent force responses of rat tails under compression. The identified mechanical behavior of the tail can help improve the rat-tail model and its applications.

3.
J Phys Chem A ; 128(18): 3711-3725, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38683599

RESUMO

Recent work in combustion and atmospheric chemistry has revealed cases in which diastereomers must be distinguished to accurately model a reacting flow. This paper presents an open-source framework for introducing such stereoisomer resolution into a kinetic mechanism. We detail our definitions and algorithms for labeling and enumerating the stereoisomers of a molecule and then generalize our system to describe the transition state (TS) of a reaction. This allows for the stereospecific enumeration of reactants and products while accounting for "fleeting" stereochemistry that is unique to the TS. We also present the AutoMech Chemical Identifier (AMChI), an InChI-like string identifier that accounts for stereocenters omitted by InChI. This identifier is extended to describe the TSs of reactions, providing a universal lookup key for specific reaction channels. The final piece of our methodology is an analytic formula to remove redundancy from a stereoresolved mechanism when its enantiomers exist as a racemic mixture, making it as compact as possible while fully accounting for the differences between diastereomers. In applying our methodology to two subsets of the NUIGMech1.1 mechanism, we find that our approach reduces the extra species added for large-fuel oxidation from 2231 (133%, full expansion) to 694 (41%, nonredundant expansion). We also find that for pyrolysis more than a quarter of the species in the expanded mechanism cannot be properly described by an InChI string, requiring an AMChI string to communicate their identity. Finally, we find that roughly one-quarter of the large-fuel oxidation reactions and one-third of the pyrolysis reactions include fleeting TS stereochemistry, which may have relevant effects on their kinetics.

4.
JHEP Rep ; 6(4): 100993, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38425452

RESUMO

Background & Aims: Maintenance of abstinence in alcohol-related liver disease (ARLD) is a major unmet therapeutic need. Digital therapeutics can deliver ongoing behavioural therapy, in real-time, for chronic conditions. The aim of this project was to develop and clinically test AlcoChange, a novel digital therapeutic for ARLD. Methods: AlcoChange was developed using validated behaviour change techniques and a digital alcohol breathalyser. This was an open-label, single-centre study. Patients with ARLD, ongoing alcohol use (within 1 month) and possession of a suitable smartphone were eligible. Patients were recruited from inpatient and outpatient settings, and received AlcoChange therapy for 3 months. The primary outcome was reduction in alcohol use from baseline to 3 months, measured by timeline follow-back. Secondary outcomes included: (i) compliance with the AlcoChange app, (ii) alcohol-related and all-cause hospital re-admissions up to 1 year, (iii) qualitative analysis to determine factors associated with compliance. Results: Sixty-five patients were recruited, of whom 41 completed the study per protocol. Patients compliant with the intervention (>60 logins over 3 months) had a significant reduction in alcohol use from baseline compared to non-compliant patients (median [IQR]: -100% [100% to -55.1%] vs. -57.1% [-95.3% to +32.13%], p = 0.029). The proportion attaining abstinence at 3 months was higher in the compliant group (57.1% vs. 22.2%, p = 0.025). The compliant group had a significantly decreased risk of subsequent alcohol-related re-admission up to 12 months (p = 0.008). Qualitative analysis demonstrated that receiving in-app feedback and the presence of a health-related 'sentinel event' were predictors of compliance with the intervention. Conclusions: Use of the novel digital therapeutic, AlcoChange, was associated with a significant reduction in alcohol use and an increase in the proportion of patients with ARLD attaining abstinence. Definitive randomised trials are warranted for this intervention. Impact and implications: Alcohol-related liver disease (ARLD) is an increasing health problem worldwide. The main cause of death and disability in ARLD is ongoing alcohol consumption, but few patients receive medications or talking therapy to maintain abstinence. This study demonstrated that a digital therapeutic, linked to a smartphone, may help reduce alcohol consumption and alcohol-related hospital admissions in these patients. If validated in larger, randomised, trials, digital therapeutics may have a role in the primary and secondary prevention of complicatons from ARLD.

6.
Int J Radiat Oncol Biol Phys ; 118(3): 859-863, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37778423

RESUMO

PURPOSE: Consistency of nomenclature within radiation oncology is increasingly important as big data efforts and data sharing become more feasible. Automation of radiation oncology workflows depends on standardized contour nomenclature that enables toxicity and outcomes research, while also reducing medical errors and facilitating quality improvement activities. Recommendations for standardized nomenclature have been published in the American Association of Physicists in Medicine (AAPM) report from Task Group 263 (TG-263). Transitioning to TG-263 requires creation and management of structure template libraries and retraining of staff, which can be a considerable burden on clinical resources. Our aim is to develop a program that allows users to create TG-263-compliant structure templates in English, Spanish, or French to facilitate data sharing. METHODS AND MATERIALS: Fifty-three premade structure templates were arranged by treated organ based on an American Society for Radiation Oncology (ASTRO) consensus paper. Templates were further customized with common target structures, relevant organs at risk (OARs) (eg, spleen for anatomically relevant sites such as the gastroesophageal junction or stomach), subsite- specific templates (eg, partial breast, whole breast, intact prostate, postoperative prostate, etc) and brachytherapy templates. An informal consensus on OAR and target coloration was also achieved, although color selections are fully customizable within the program. RESULTS: The resulting program is usable on any Windows system and generates template files in practice-specific Digital Imaging and Communications In Medicine (DICOM) or XML formats, extracting standardized structure nomenclature from an online database maintained by members of the TG-263U1, which ensures continuous access to up-to-date templates. CONCLUSIONS: We have developed a tool to easily create and name DICOM radiation therapy (DICOM-RT) structures sets that are TG-263-compliant for all planning systems using the DICOM standard. The program and source code are publicly available via GitHub to encourage feedback from community users for improvement and guide further development.


Assuntos
Braquiterapia , Radioterapia (Especialidade) , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Software , Braquiterapia/métodos
7.
Dermatol Surg ; 49(12): 1128-1130, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910643

RESUMO

BACKGROUND: Although patient satisfaction with reconstructive outcomes after facial skin cancer resection is an important consideration in Mohs surgery, there is limited information evaluating this concern using validated patient-reported outcome tools. OBJECTIVE: To characterize predictors that may be associated with increased postoperative patient satisfaction with facial appearance after Mohs surgery using the FACE-Q/Skin Cancer survey, a patient-reported outcome tool that has been validated in various studies. METHODS: A total of 202 patients who underwent Mohs surgery for facial skin cancer at the Brigham and Women's Faulkner Hospital between April 2017 and November 2021 were included after completing the postoperative Satisfaction with Facial Appearance scale (FACE-Q scale). RESULTS: Male patients were significantly more likely to have higher satisfaction scores compared with female patients (aOR 2.4, 95% CI 1.1-5.1). Increased preoperative facial satisfaction scores was directly correlated with increased postoperative facial satisfaction scores ( p < .01). Patients with tumors on the lower face/neck (aOR 3.88; 95% CI 1.4-10.7) had significantly greater satisfaction scores compared with those with tumors on their nose/nasolabial folds. CONCLUSION: Potential interventions and counseling methods can be tailored toward specific patient populations with lower satisfaction scores to increase their overall satisfaction with reconstructive outcomes.


Assuntos
Neoplasias Faciais , Neoplasias Cutâneas , Humanos , Masculino , Feminino , Satisfação do Paciente , Cirurgia de Mohs , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/psicologia , Nariz/cirurgia , Neoplasias Faciais/cirurgia , Sulco Nasogeniano/cirurgia
8.
JAMA Dermatol ; 159(12): 1332-1338, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37851425

RESUMO

Importance: Perineural invasion (PNI) is an adverse risk feature in cutaneous squamous cell carcinoma (CSCC) that affects patient prognosis and disease management. However, research comparing different PNI patterns on patient outcomes is limited. Objective: To compare 4 assessments of PNI in CSCC, their associations with poor outcomes, and implications for their inclusion in the Brigham and Women's Hospital (BWH) staging system. Design, Setting, and Participants: This retrospective cohort study was performed at a single tertiary care institution and compared 4 PNI assessments: nerve caliber, number of involved nerves per section, PNI maximal depth, and PNI location with respect to tumor. Patients with primary, localized, invasive CSCC with PNI diagnosed between January 1, 2000, and December 31, 2017, were identified via an electronic in-house database. Available pathology slides were secondarily reviewed by study authors. Relevant patient and tumor characteristics and outcomes were abstracted from the medical record. Data analysis was performed between September 6 and October 20, 2022. Main Outcomes and Measures: Risks of recurrence, disease-specific death, and a composite end point (any poor outcome) were calculated via multivariable stepwise Fine and Gray competing-risks regression. Considered revisions to the BWH staging system were assessed via receiver operating characteristic curves and test characteristics. Results: This study included 140 patients with CSCC, with a mean (SD) age of 75.1 (11.2) years. More than half of the patients were men (93 [66.4%]), and most identified as White (132 [94.3%]). Of the 4 PNI assessments studied, only involvement of multiple nerves was associated with poor outcomes. Perineural invasion of 5 or more distinct nerves (extensive PNI [ePNI]) was independently associated with local recurrence (subhazard ratio [SHR], 13.83 [95% CI, 3.50-54.62]; P < .001), disease-specific death (SHR, 6.20 [95% CI, 1.59-24.21]; P = .009), and any poor outcome (SHR, 10.21 [95% CI, 2.88-36.15]; P < .001). A revised BWH staging system with substitution of ePNI for large-caliber PNI resulted in improved area under the curve and test characteristics compared with current BWH staging criteria that use nerve caliber as the measure of PNI. Conclusions and Relevance: The findings of this cohort study suggest that ePNI is the best prognostic measure of PNI. Because ePNI obviated the need for a micrometer and had superior prognostic capacity to nerve caliber in this cohort, ePNI should be considered for inclusion in CSCC tumor staging. Inclusion of ePNI as a high-risk factor in CSCC staging systems may optimize patient selection for primary treatment and adjuvant interventions.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Masculino , Humanos , Feminino , Idoso , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Prognóstico , Estadiamento de Neoplasias , Invasividade Neoplásica/patologia
10.
Free Radic Biol Med ; 207: 45-47, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37453234
11.
J Mech Med Biol ; 23(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-37361026

RESUMO

The anterior and posterior iliac spine markers frequently used to define the pelvis, are commonly occluded during three-dimensional (3D) motion capture. The occlusion of these markers leads to the use of various tracking marker configurations on the pelvis, which affect kinematic results. The purpose of this investigation was to examine the agreement of CODA pelvis kinematic results when two different tracking marker configurations were used during roofing tasks. 3D motion data were collected on seven male subjects while mimicking two roofing tasks. Hip joint angles (HJAs) were computed using the CODA pelvis with two different tracking marker configurations, the trochanter tracking method (TTM), and virtual pelvis tracking method (VPTM). Agreement between tracking marker configurations was assessed using cross-correlations, bivariate correlations, mean absolute differences (MADs), and Bland-Altman (BA) plots. The correlations displayed no time lag and strong agreement (all r > 0.83) between the HJA from the VPTM and TTM, suggesting the timing occurrence of variables are comparable between the two tracking marker configurations. The MAD between the VPTM and TTM displayed magnitude differences, but most of the differences were within a clinically acceptable range. Caution should still be used when comparing kinematic results between various tracking marker configurations, as differences exist.

13.
Biomed Phys Eng Express ; 9(4)2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37336202

RESUMO

Objective. Adaptive Radiotherapy (ART) is an emerging technique for treating cancer patients which facilitates higher delivery accuracy and has the potential to reduce toxicity. However, ART is also resource-intensive, Requiring extra human and machine time compared to standard treatment methods. In this analysis, we sought to predict the subset of node-negative cervical cancer patients with the greatest benefit from ART, so resources might be properly allocated to the highest-yield patients.Approach. CT images, initial plan data, and on-treatment Cone-Beam CT (CBCT) images for 20 retrospective cervical cancer patients were used to simulate doses from daily non-adaptive and adaptive techniques. We evaluated the coefficient of determination (R2) between dose and volume metrics from initial treatment plans and the dosimetric benefits to theBowelV40Gy,BowelV45Gy,BladderDmean,andRectumDmeanfrom adaptive radiotherapy using reduced 3 mm or 5 mm CTV-to-PTV margins. The LASSO technique was used to identify the most predictive metrics forBowelV40Gy.The three highest performing metrics were used to build multivariate models with leave-one-out validation forBowelV40Gy.Main results. Patients with higher initial bowel doses were correlated with the largest decreases in BowelV40Gyfrom daily adaptation (linear best fit R2= 0.77 for a 3 mm PTV margin and R2= 0.8 for a 5 mm PTV margin). Other metrics had intermediate or no correlation. Selected covariates for the multivariate model were differences in the initialBowelV40GyandBladderDmeanusing standard versus reduced margins and the initial bladder volume. Leave-one-out validation had an R2of 0.66 between predicted and true adaptiveBowelV40Gybenefits for both margins.Significance. The resulting models could be used to prospectively triage cervical cancer patients on or off daily adaptation to optimally manage clinical resources. Additionally, this work presents a critical foundation for predicting benefits from daily adaptation that can be extended to other patient cohorts.


Assuntos
Radioterapia Guiada por Imagem , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos , Radioterapia Guiada por Imagem/métodos , Radiometria/métodos
14.
J Pediatr Orthop ; 43(8): e686-e691, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37311655

RESUMO

BACKGROUND: Pediatric patients with leg length discrepancies and complex deformities may require multiplanar external fixators for correction. We have encountered 4 cases of half-pin breakage with the Orthex hexapod frame. The purpose of this study is to report factors associated with half-pin breakage and compare various deformity correction characteristics between 2 hexapod frames - Taylor Spatial Frame (TSF) and Orthex. METHODS: Pediatric patients with lower extremity deformities treated with an Orthex or TSF at a single tertiary children's hospital between 2012 and 2022 were included for retrospective review. Variables compared between frame groups include frame configuration, half-pin/wire fixation, length achieved, angular correction, and frame time. RESULTS: There were 23 Orthex frames (23 patients) and 36 TSF (33 patients) included. Four Orthex and zero TSF had proximal half-pin breakage. The Orthex group was younger on average (10 vs. 12 y, P =.04*) at the time of frame placement. The majority (52%) of Orthex frames were used for simultaneous lengthening and angular correction, while the majority (61%) of TSF was used for only angular correction. Orthex had more half-pins used for proximal fixation (median 3 vs. 2, P <0.0001*) and more frames with nonstandard configuration (7 (30%) vs. 1 (3%), P =0.004*). Orthex group had a longer total frame time (median 189 vs. 146 days, P =0.012*) and longer time required for regenerate healing (117 vs. 89 d, P =0.02*). There were no significant differences in length gained, angular correction, or healing index between Orthex and TSF. Nonstandard configuration, increased number of proximal half-pins, younger age at index surgery, and increased lengthening were associated with pin breakage. CONCLUSIONS: This is the first study to report half-pin breakage while using multiplanar frames in pediatric lower extremity deformity correction. The Orthex and TSF groups consisted of significantly different patients and frame configurations, making it difficult to identify any specific cause for pin breakage. This study shows that pin breakage is likely caused by multiple factors and is associated with the increased complexity of deformity correction. LEVEL OF EVIDENCE: Level III-Retrospective Comparison Study.


Assuntos
Fixadores Externos , Desigualdade de Membros Inferiores , Humanos , Criança , Estudos Retrospectivos , Desigualdade de Membros Inferiores/cirurgia , Pinos Ortopédicos , Complicações Pós-Operatórias
15.
AIDS Behav ; 27(10): 3460-3467, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37036593

RESUMO

Despite evidence supporting HIV pre-exposure prophylaxis (PrEP) effectiveness, very few women with opioid use disorder (OUD) take PrEP. Interventions that improve medication assisted treatment (MAT) uptake and adherence may also be beneficial for PrEP. The reSET-O mobile phone app is a component of the evidence-based Therapeutic Education System, which improves retention and abstinence for people with OUD. To better understand use of this mobile health tool as a support for PrEP among women with OUD, pre-implementation contextual inquiry is needed. Therefore, we set out to assess target user characteristics, implementation barriers, feasibility, and acceptability of reSET-O. We recruited women with OUD receiving care from a community-based organization in Philadelphia to complete semi-structured interviews. All participants were prescribed reSET-O. We interviewed 20 participants (average age 37 years; 70% white, 15% Hispanic, 5% Black) from 5/2021 to 2/2022. We used an integrated analysis approach combining modified grounded theory and implementation science constructs. Half reported recent injection drug use, and 6 were taking buprenorphine. Mental health symptoms were common, and half described engaging in transactional sex. The majority expressed strong interest in PrEP. Participants reported the app would be highly acceptable for PrEP and MAT adherence support, but only two redeemed the prescription. The most common barriers included phone and internet access. Our findings highlight potential implementation challenges for the use of such an app to support PrEP use in this population. Poor uptake of the app at follow-up indicates that initial prescription redemption is a major barrier to reSET-O implementation.


Assuntos
Telefone Celular , Infecções por HIV , Aplicativos Móveis , Transtornos Relacionados ao Uso de Opioides , Profilaxia Pré-Exposição , Humanos , Feminino , Adulto , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Estudos de Viabilidade
16.
Clin Transl Gastroenterol ; 14(6): e00587, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37019645

RESUMO

INTRODUCTION: The efficacy of targeted albumin therapy in the management of decompensatory events in cirrhosis is unclear, with different reports showing conflicting results. It is possible that only certain subgroups of patients may benefit from targeted albumin administration. However, extensive conventional subgroup analyses have not yet identified these subgroups. Albumin is an important regulator of physiological networks and may interact with homeostatic mechanism differently in patients according to the integrity of their physiological network. In this study, we aimed to assess the value of network mapping in predicting response to targeted albumin therapy in patients with cirrhosis. METHODS: This is a substudy of the ATTIRE trial, a multicenter randomized trial conducted to assess the effect of targeted albumin therapy in cirrhosis. Baseline serum bilirubin, albumin, sodium, creatinine, CRP, white cell count (WCC), international normalized ratio, heart rate, and blood pressure of 777 patients followed up for 6 months were used for network mapping using parenclitic analysis. Parenclitic network analysis involves measuring the deviation of each patient from the existing network of physiological interactions in a reference population. RESULTS: Overall network connectivity and deviations along the WCC-CRP axis predicted 6-month survival independent of age and model for end-stage liver disease in the standard care arm. Patients with lower deviation along the WCC-CRP axis showed lower survival in response to targeted albumin administration over a 6-month follow-up period. Likewise, patients with higher overall physiological connectivity survived significantly less than the standard care group after targeted albumin infusion. DISCUSSION: The parenclitic network mapping can predict the survival of patients with cirrhosis and identify patient subgroups that do not benefit from targeted albumin therapy.


Assuntos
Doença Hepática Terminal , Humanos , Índice de Gravidade de Doença , Albuminas/uso terapêutico , Cirrose Hepática , Testes de Função Hepática
17.
J Am Acad Dermatol ; 89(2): 254-260, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37121483

RESUMO

BACKGROUND: The preferred treatment for clinically node-negative Merkel cell carcinoma (MCC) is surgical excision in conjunction with sentinel lymph node biopsy. There is limited large-scale research on survival outcomes by surgical approach for management of the primary tumor. OBJECTIVE: To compare overall and MCC-specific survival outcomes in clinically and pathologically, node-negative MCC patients treated with wide-local excision (WLE) and Mohs micrographic surgery (MMS) in a nationally representative sample. METHODS: Overall and MCC-specific survival outcomes for primary MCC tumors contained in the SEER (Surveillance, Epidemiology, and End Results)-18 database from 1989 to 2015 were stratified by surgical modality and analyzed via competing risk analysis. RESULTS: A total of 2359 US adults with MCC were included in the analysis. For overall and MCC-specific survival, there was no significant difference in survival outcomes between WLE and MMS on multivariable analysis (hazard ratio, 1.04 [95% CI, 0.88-1.22]; subdistribution hazard ratio, 0.76 [95% CI, 0.53-1.09]). Sentinel lymph node biopsy was associated with improved overall survival and MCC-specific survival. LIMITATIONS: Retrospective design of SEER and the lack of covariates such as comorbidities and immunostaining. CONCLUSION: There is no survival disadvantage for MMS compared to WLE as the surgical modality for primary cutaneous MCC. Sentinel lymph node biopsy should be coordinated prior to MMS.


Assuntos
Carcinoma de Célula de Merkel , Neoplasias Cutâneas , Adulto , Humanos , Cirurgia de Mohs/métodos , Neoplasias Cutâneas/patologia , Estudos Retrospectivos , Modelos de Riscos Proporcionais , Recidiva Local de Neoplasia/cirurgia
18.
Phys Med Biol ; 68(8)2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36898161

RESUMO

Objective. To lay the foundation for automated knowledge-based brachytherapy treatment planning using 3D dose estimations, we describe an optimization framework to convert brachytherapy dose distributions directly into dwell times (DTs).Approach. A dose rate kerneld(r,θ,φ)was produced by exporting 3D dose for one dwell position from the treatment planning system and normalizing by DT. By translating and rotating this kernel to each dwell position, scaling by DT and summing over all dwell positions, dose was computed (Dcalc). We used a Python-coded COBYLA optimizer to iteratively determine the DTs that minimize the mean squared error betweenDcalcand reference doseDref, computed using voxels withDref80%-120% of prescription. As validation of the optimization, we showed that the optimizer replicates clinical plans whenDref= clinical dose in 40 patients treated with tandem-and-ovoid (T&O) or tandem-and-ring (T&R) and 0-3 needles. Then we demonstrated automated planning in 10 T&O usingDref= dose predicted from a convolutional neural network developed in past work. Validation and automated plans were compared to clinical plans using mean absolute differences (MAD=1N∑n=1Nabsxn-xn') over all voxels (xn= Dose,N= #voxels) and DTs (xn= DT,N= #dwell positions), mean differences (MD) in organD2ccand high-risk CTV D90 over all patients (where positive indicates higher clinical dose), and mean Dice similarity coefficients (DSC) for 100% isodose contours.Main results. Validation plans agreed well with clinical plans (MADdose= 1.1%, MADDT= 4 s or 0.8% of total plan time,D2ccMD = -0.2% to 0.2% and D90 MD = -0.6%, DSC = 0.99). For automated plans, MADdose= 6.5% and MADDT= 10.3 s (2.1%). The slightly higher clinical metrics in automated plans (D2ccMD = -3.8% to 1.3% and D90 MD = -5.1%) were due to higher neural network dose predictions. The overall shape of the automated dose distributions were similar to clinical doses (DSC = 0.91).Significance. Automated planning with 3D dose predictions could provide significant time savings and standardize treatment planning across practitioners, regardless of experience.


Assuntos
Braquiterapia , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/radioterapia , Braquiterapia/métodos , Dosagem Radioterapêutica , Benchmarking , Planejamento da Radioterapia Assistida por Computador/métodos
19.
Int J Radiat Oncol Biol Phys ; 115(1): 224-232, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36289039

RESUMO

PURPOSE: Our purpose was to investigate the effect of physicist-patient consults on patient anxiety and patient satisfaction with a randomized prospective phase III clinical trial. METHODS AND MATERIALS: Sixty-six patients were randomly assigned to the physics direct patient care (PDPC) arm or the control arm of the trial. Patients assigned to the PDPC arm received 2 physicist-patient consults to educate them on the technical aspects of their radiation therapy, while patients assigned to the control arm received the standard of care (ie, standard radiation therapy workflow without any additional physicist-patient consults). Questionnaires were administered to all patients at 4 time points (after enrollment, after the simulation, after the first treatment, and after the last treatment) to assess anxiety and satisfaction. RESULTS: The decrease in anxiety for the PDPC arm, compared with the control arm, was statistically significant at the first treatment (P = .027) time point. The increase in technical satisfaction for the PDPC arm, compared with the control arm, was statistically significant at the simulation (P = .005), first treatment (P < .001), and last treatment (P = .002) time points. The increase in overall satisfaction for the PDPC arm, compared with the control arm, was statistically significant at the first treatment (P = .014) and last treatment (P = .001) time points. CONCLUSIONS: Physicist-patient consults improved the patient experience by decreasing anxiety and increasing satisfaction. Future work is needed to modify current radiation oncology workflows and medical physics responsibilities to allow all patients to benefit from this advancement in patient care.


Assuntos
Radioterapia (Especialidade) , Humanos , Estudos Prospectivos , Assistência ao Paciente , Satisfação do Paciente , Inquéritos e Questionários
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