Browsing by Author "Obeng-Gyasi, Samilia"

Now showing 1 - 6 of 6
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    A fiber optoacoustic guide with augmented reality for precision breast-conserving surgery
    (Springer Nature, 2018-05-18) Lan, Lu; Xia, Yan; Li, Rui; Liu, Kaiming; Mai, Jieying; Medley, Jennifer Anne; Obeng-Gyasi, Samilia; Han, Linda K.; Wang, Pu; Cheng, Ji-Xin; Radiology and Imaging Sciences, School of Medicine
    Lumpectomy, also called breast-conserving surgery, has become the standard surgical treatment for early-stage breast cancer. However, accurately locating the tumor during a lumpectomy, especially when the lesion is small and nonpalpable, is a challenge. Such difficulty can lead to either incomplete tumor removal or prolonged surgical time, which result in high re-operation rates (~25%) and increased surgical costs. Here, we report a fiber optoacoustic guide (FOG) with augmented reality (AR) for sub-millimeter tumor localization and intuitive surgical guidance with minimal interference. The FOG is preoperatively implanted in the tumor. Under external pulsed light excitation, the FOG omnidirectionally broadcasts acoustic waves through the optoacoustic effect by a specially designed nano-composite layer at its tip. By capturing the acoustic wave, three ultrasound sensors on the breast skin triangulate the FOG tip's position with 0.25-mm accuracy. An AR system with a tablet measures the coordinates of the ultrasound sensors and transforms the FOG tip's position into visual feedback with <1-mm accuracy, thus aiding surgeons in directly visualizing the tumor location and performing fast and accurate tumor removal. We further show the use of a head-mounted display to visualize the same information in the surgeons' first-person view and achieve hands-free guidance. Towards clinical application, a surgeon successfully deployed the FOG to excise a "pseudo tumor" in a female human cadaver. With the high-accuracy tumor localization by FOG and the intuitive surgical guidance by AR, the surgeon performed accurate and fast tumor removal, which will significantly reduce re-operation rates and shorten the surgery time.
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    Financial Toxicity Is Associated With Worse Physical and Emotional Long-term Outcomes After Traumatic Injury
    (Wolters Kluwer, 2019-11) Murphy, Patrick B.; Severance, Sarah; Savage, Stephanie; Obeng-Gyasi, Samilia; Timsina, Lava R.; Zarzaur, Ben L.; Surgery, School of Medicine
    Background Increasing healthcare costs and high deductible insurance plans have shifted more responsibility for medical costs to patients. After serious illnesses, financial responsibilities may result in lost wages, forced unemployment, and other financial burdens, collectively described as financial toxicity. Following cancer treatments, financial toxicity is associated with worse long-term health related quality of life outcomes (HRQOL). The purpose of this study was to determine the incidence of financial toxicity following injury, factors associated with financial toxicity, and the impact of financial toxicity on long-term HRQOL. Methods Adult patients with an injury severity score of 10 or greater and without head or spinal cord injury were prospectively followed for 1 year. The Short-Form-36 was used to determine overall quality of life at 1, 2, 4 and 12 months. Screens for depression and post-traumatic stress syndrome (PTSD) were administered. The primary outcome was any financial toxicity. A multivariable generalized estimating equation was used to account for variability over time. Results 500 patients were enrolled and 88% suffered financial toxicity during the year following injury (64% reduced income, 58% unemployment, 85% experienced stress due to financial burden). Financial toxicity remained stable over follow-up (80–85%). Factors independently associated with financial toxicity were lower age (OR 0.96 [0.94–0.98]), and lack of health insurance (OR 0.28 [0.14–0.56]) and larger household size (OR 1.37 [1.06–1.77]). After risk adjustment, patients with financial toxicity had worse HRQOL, and more depression and PTSD in a step-wise fashion based on severity of financial toxicity. Conclusions Financial toxicity following injury is extremely common and is associated with worse psychological and physical outcomes. Age, lack of insurance, and large household size are associated with financial toxicity. Patients at risk for financial toxicity can be identified and interventions to counteract the negative effects should be developed to improve long-term outcomes. Level of Evidence Prognostic/epidemiologic study, level III
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    High‐speed Intraoperative Assessment of Breast Tumor Margins by Multimodal Ultrasound and Photoacoustic Tomography
    (Wiley, 2018) Lu, Rui; Lan, Lu; Xia, Yan; Wang, Pu; Han, Linda K.; Dunnington, Gary L.; Obeng-Gyasi, Samilia; Sandusky, George E.; Medley, Jennifer A.; Crook, Susan T.; Cheng, Ji-Xin; Medicine, School of Medicine
    Conventional methods for breast tumor margins assessment need a long turnaround time, which may lead to re‐operation for patients undergoing lumpectomy surgeries. Photoacoustic tomography (PAT) has been shown to visualize adipose tissue in small animals and human breast. Here, we demonstrate a customized multimodal ultrasound and PAT system for intraoperative breast tumor margins assessment using fresh lumpectomy specimens from 66 patients. The system provides the margin status of the entire excised tissue within 10 minutes. By subjective reading of three researchers, the results show 85.7% [95% confidence interval (CI), 42.0% ‐ 99.2%] sensitivity and 84.6% (95% CI, 53.7% ‐ 97.3%) specificity, 71.4% (95% CI, 30.3% ‐ 94.9%) sensitivity and 92.3% (95% CI, 62.1% ‐ 99.6%) specificity, and 100% (95% CI, 56.1% ‐ 100%) sensitivity and 53.9% (95% CI, 26.1% ‐ 79.6%) specificity respectively when cross‐correlated with post‐operational histology. Furthermore, a machine learning‐based algorithm is deployed for margin assessment in the challenging ductal carcinoma in situ tissues, and achieved 85.5% (95% CI, 75.2% ‐ 92.2%) sensitivity and 90% (95% CI, 79.9% ‐ 95.5%) specificity. Such results present the potential of using mutlimodal ultrasound and PAT as a high‐speed and accurate method for intraoperative breast tumor margins evaluation.
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    The Implications of Insurance Status on Presentation, Surgical Management and Mortality among Non-Metastatic Breast Cancer Patients in Indiana
    (Elsevier, 2018-12) Obeng-Gyasi, Samilia; Timsina, Lava; Miller, Kathy D.; Ludwig, Kandice K.; Fisher, Carla S.; Haggstrom, David A.; Obstetrics and Gynecology, School of Medicine
    Background The National Breast and Cervical Cancer Early Detection Program seeks to reduce health care disparities by providing uninsured and underinsured women access to screening mammograms. The objective of this study is to identify the differences in presentation, surgical management, and mortality among nonmetastatic uninsured patients diagnosed through Indiana's Breast and Cervical Cancer Program compared with patients with private and government (Medicare or Medicaid) insurance. Methods Study data were obtained using the Indiana state cancer registry and Indiana's Breast and Cervical Cancer Program. Women aged 50 to 64 with an index diagnosis of stage 0 to III breast cancer from January 1, 2006 to December 31, 2013, were included in the study. Bivariate intergroup analysis was conducted. Kaplan-Meier estimates between insurance types were compared using the log rank test. All-cause mortality was evaluated using a mixed effects model. Results The groups differed significantly for sociodemographic and clinical variables. Uninsured Indiana Breast and Cervical Cancer Program patients presented with later disease stage (P < .001) and had the highest overall mortality (hazard ratio 2.2, P = .003). Surgical management only differed among stage III patients (P = .012). Conclusion To improve insurance-based disparities in Indiana, implementation of the Breast and Cervical Cancer Program in conjunction with expansion of insurance coverage to vulnerable low-income populations need to be optimized.
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    Oncology clinical trials and insurance coverage: An update in a tenuous insurance landscape
    (Wiley, 2019-06-28) Obeng-Gyasi, Samilia; Kircher, Sheetal M.; Lipking, Kelsey P.; Keele, Benjamin J.; Benson, Al B.; Wagner, Lynne I.; Carlos, Ruth C.; Robert H. McKinney School of Law
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    Three Essays on the Impact of Medicaid Expansion on Cancer Care and Mis-Measured Self-Reports of Cancer Screening Status
    (2022-09) Bhattacharyya, Oindrila; Morrison, Gwendolyn; Tennekoon, Vidhura; Royalty, Anne; Ottoni-Wilhelm, Mark; Xu, Huiping; Obeng-Gyasi, Samilia
    The dissertation consists of three essays attempting to assess the impact of expanded health insurance policy on cancer care continuum and measure the unbiased program effects after taking care of mis-measured cancer screening self-reports. The first essay examines the impact of the Affordable Care Act’s Medicaid expansion on time to oral cancer treatment initiation since diagnosis, quality of hospital care such as length of stay in the hospital, planned and unplanned readmissions post-surgery, and care outcome such as ninety-day mortality since surgery. The study uses two-way fixed effects linear model analysis under a difference-in-difference estimation setting to show that Medicaid expansion eligibility reduced overall oral cancer treatment initiation timing since diagnosis, including radiation initiation as well as first surgery of the primary site. It also shortened the length of stay in the hospital post-surgery. The second essay assesses the value of electronic medical records from Indiana health information exchange (IHIE) and survey self-reports of Indiana residents seen at Indiana University Health in measuring population-based cancer screening for colorectal, cervical, and breast cancer. Between the two measures of screening, the study examines association using Spearman’s rank correlation and concordance using Percent Agreement and Gwet’s Agreement Coefficient. Health information exchange and self-reports, both provided unique information in measuring cancer screening, and the most robust measurement approach entails collecting screening information from both HIE and patient self-report. In this study, we find evidence of measurement error in self-reports in terms of reporting bias. The majority of the publicly available datasets collect information on cancer screening behavior through patient interviews which are self-reported and may suffer from potential measurement errors. The third essay uses a nationwide population-based database and examines the true, unbiased impact of Medicaid expansion on cancer screening for breast, colorectal, cervical, and prostate cancers after correcting for any bias due to possible misclassification of the self-reported screening status. This study conducts a modified two-way fixed effects probit model under a difference-in-difference estimation setting to identify and correct the errors in the self-reports and estimate the unbiased program effect which shows positive impact on cancer screening with increased effect sizes.