Browsing by Subject "Diagnostic Imaging"
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Item Clinical applications of transesophageal echocardiography(1993-08-26) Grayburn, Paul A.Item Comprehensive Analysis of Lung Cancer Prognostic Factors(2019-07-29) Wang, Shidan; Gerber, David E.; Xie, Yang; Xiao, Guanghua; Zhan, Xiaowei; Hoshida, YujinLung cancer is the leading cause of death from cancer. It is remarkably heterogeneous in histopathological features and highly variable in prognosis. Analysis of prognostic factor is anticipated to guide clinicians for treatment selection, enhance patient care, and help understanding biological mechanism of tumor progression. To extend current knowledge about lung cancer prognosis, this dissertation analyzed lung cancer prognostic factors in three levels. First, in tumor level, deep learning aided pathology image analysis was used to extract tumor geometry and microenvironment features, upon which an image-based survival prediction model was built and independently validated for lung adenocarcinoma. Second, in patient level, a nomogram was built with demographic and clinical variables for patients with small cell lung cancer. The nomogram was implemented online for public usage. Third, in population level, how facility type and volume affect survival outcome and surgery selection for early stage non-small cell lung cancer was analyzed.Item Development of Iron Oxide Based Nanoparticles as Dual-Modality Imaging Probes(2008-09-12) Guo, Yi; Sun, XiankaiDual-modality (MR/nuclear) imaging can combine exquisite anatomical resolution with superior molecular sensitivity, and significantly facilitate the accuracy of cancer diagnosis. However, the application of this technique is hampered by the paucity of sensitive dual-modality imaging probes that target tumors specifically. Here we synthesized dual-modality imaging probes by doping positron- or gamma-emitting nuclides to the core of dextran-coated superparamagnetic iron oxide nanoparticles (NUSPIONs). The synthesized nanoparticles were characterized by dynamic light scattering (DLS), transmission electron microscope (TEM), atomic force microscope (AFM), and high performance liquid chromatography (HPLC). The evaluations of these nanoparticles were performed both in vitro and in vivo. Four radioisotopes (111In, 177Lu, 64Cu, and 77As) were successfully incorporated into the core of nanoparticles. The purification of nanoparticles via centricon filter accelerated the separation process effectively without apparent aggregation. These nanoparticles exhibited good in vitro stability in both phosphate buffered saline (> 99% intact) and rat serum (> 92% intact) out to 72 h, and the high r2-to-r1 ratio indicating their potential as MRI T2 contrast agents. Two distinctly sized 177Lu-doped nanoparticles (NUSPION-1 and NUSPION-2 with hydrodynamic radii of 11.8 ��3 nm and 30.6 ��5 nm respectively) were used for biodistribution studies in normal mice. NUSPION-1 showed significantly (p < 0.0001) higher uptake and longer retention in blood and less uptake in liver and spleen than NUSPION-2, which is advantageous for both passive and active targeting. Due to its optimal tissue distribution pattern, NUSPION-1 was chosen for further in vivo evaluation in PC-3 tumor-bearing mice. High tumor uptake and contrast ratios of tumor-to-muscle and tumor-to-blood were observed. A proof-of-principle dual-modality imaging study was carried out by a virtually single-dose injection in PC-3 tumor-bearing mice. The tumors were visualized by both MRI and autoradiography. Post-MRI Prussian blue iron staining and post-autoradiographic imaging biodistribution confirmed the accumulation of nanoparticles in tumors. Taken together, we have demonstrated a practical method to develop iron oxide based MRI/nuclear imaging probes.Item Evaluation of the Light Emission Kinetics in Luciferin/Luciferase-Based In Vivo Bioluminescence Imaging for Guidance in the Development of Small Animal Imaging Study Design(2006-05-15) Bollinger, Robert Albin; Mason, Ralph P.Bioluminescence imaging (BLI) is gaining acceptance as a small animal imaging modality useful for visualizing cellular and molecular activity in vivo, and especially for evaluating tumor development and efficacies of treatments. Various studies have validated the technique for a number of purposes, including the quantification of tumor burden; however, many basic questions have not been investigated whose answers may ultimately impact the conclusions drawn from the results. Primarily, consideration of the impact of BLI emission kinetics has not been rigorously addressed. This study provides information on the effects of different routes of luciferin substrate injection on the BLI kinetic profile, including time to peak emission, magnitude of peak emission, and emission decay characteristics. This study also presents for the first time the use of subcutaneous (s.c.) luciferin injection and the use of s.c. luciferin injection followed by continuous s.c. infusion (s.c.i.) for establishment of stable BLI light emission. Further, results are presented of the kinetic profile changes associated with 1) inhaled and injected anesthesia; and 2) ambient air heating on mouse core temperature. The study demonstrated substantial differences in the peak light emission with i.v. providing the highest, with s.c., s.c.i. and i.p yielding 30% or less of the light emission of the i.v. route. The correlations between tumor burden and BLI light emission were moderately strong (R>0.75) for each administration route, but at varying times following injection, providing information for establishment of optimal image start times. Surprisingly, ambient cooling of the animal while under anesthesia yielded peak light emissions of up to 100% higher than those obtained when ambient air heating was used to maintain mouse core temperature. Finally, guidelines are presented to aid investigators in development of BLI study design to give due consideration to luciferin administration routes, anesthesia protocol, and animal temperature maintenance.Item Facilitating Image Sharing for Patients Transferred to a Tertiary Care Center Through Process Assessment and Identification of Quality Indicators in Order to Improve Quality of Patient Care, Reduce Healthcare Costs, and Reduce Reimaging(2017-04-03) Patel, Roshni; Reed, W. Gary; Greilich, Philip; Brewington, CeceliaBACKGROUND: lifeIMAGE allows for images to be uploaded from a CD and permanently stored in PACS and also facilitates the transfer of images online via cloud-based sharing without the transfer of CDs. However, the current use of lifeIMAGE in imaging transfers remains poorly understood. Thus the aim of this study was to assess the current state of imaging transfers and ultimately to improve medical imaging handovers for patients transferred from outside hospitals to Clements University Hospital (UT Southwestern's tertiary care center) through the use of lifeIMAGE. METHODS: The Plan Do Study Act method of quality improvement was used for this project. Based on our process mapping, we created a two-pronged intervention: the first focusing on increasing online imaging transfers from outside facilities via Cloud Connection, and the second focusing on assessing and improving knowledge of uploading images from CDs. Baseline assessment included pulling data from lifeIMAGE analytics to assess the current use of lifeIMAGE, reviewing 9 months of transfer logs before the intervention, and conducting a resident survey before the intervention. INTERVENTION: The first component of the intervention involved improving the current transfer of images from outside hospitals via cloud-based image sharing, without the use of CDs. This involved reviewing transfer logs to identify which outside facilities to focus on, providing the facilities with a document explaining their options for transferring images via lifeIMAGE, and scheduling meetings with these outside facilities to work towards a collaborative effort for the online transfer of images. The second component of the intervention involved uploading images from CDs to lifeIMAGE. A survey of residents was conducted to determine healthcare providers' current practice related to medical imaging handover for patients transferred with a CD and to evaluate knowledge of uploading images. This was followed by presenting a brief PowerPoint tutorial on uploading images from CD to lifeIMAGE to Internal Medicine residents at noon conference and posting instructions on the IM Resident blog and website. RESULTS: Of the recorded transfers spanning 9 months (Dec 2015-Aug 2016) from 371 different outside facilities (after excluding hospitals within the UT Southwestern system), United Regional Health Care System Wichita Falls and Dallas VA Medical Center were the facilities that transferred the most patients to CUH: 93 (3.63%) and 52 (3.32%), respectively. 68.2% of the surveyed residents expressed that at least half of transferred patients present with a CD containing images, and 72.7% of residents expressed that repeat imaging was required in at least half of the patients because they were transferred without imaging. 61.4% of resident respondents did not know how to upload CD images to lifeIMAGE. Of the residents who knew how to upload CD images to lifeIMAGE, the majority of this group (82%) endorsed uploading images themselves. When asked to describe the current process after receiving a CD containing images, 34% of surveyed residents reported directly importing images from the CDs into lifeIMAGE; 30% of residents reported sending CDs to radiology to upload; 25% reported viewing the images on CDs without import them. CONCLUSIONS: Creating a workflow diagram and assessing baseline data through lifeIMAGE Analytics and through the resident survey improved documentation and understanding of the current state of medical imaging transfers at Clements University Hospital. This study identified that cloud-based image sharing is an underutilized capability of lifeIMAGE. It further helped narrow the scope of the intervention by identifying the two sending hospitals with the highest volume of image transfers so that we could work to increase utilization of cloud-based transfers at these institutions. Based on the resident survey data exposing knowledge as a major barrier, we presented a short tutorial to the residents during noon conference detailing how to upload images to lifeIMAGE and push the images to PACS and created a brief instruction guide that was emailed to the residents as well as posted to the IM Resident website and IM blog for future access. The survey data also indicated that the process for uploading imaging from CDs was highly variable among residents, supporting the need for an intervention to standardize practice. Future PDSA cycles will be needed to assess the impact of our interventions.Item [News](1974-01-17) Fenley, BobItem [UT Southwestern Medical Center News](2012-12-26) Lyda, AlexItem Utility of Retrograde Ureteroceleogram in Management of Complex Ureterocele(2016-01-19) Arevalo, Michelle; Prieto, JC; Bush, NC; Cost, N; Nuss, G; Brown, B; Baker, LAINTRODUCTION: Symptomatic pediatric ureterocele manifests diversely making evidence-based management impractical. Thus, detailed visualization of ureterocele anatomy prior to first surgical incision is invaluable. Retrograde ureteroceleogram (RUC) is a simple, underutilized radiologic technique that can be performed during cystoscopy. We sought to determine whether RUC changes surgical management by more accurately depicting the complex ureteral and ureterocele anatomy compared to the routine preoperative ureterocele imaging studies: ultrasound and voiding cystourethrography (VCUG). METHODS: Patients who underwent surgical management of ureterocele between 2003-2015 were identified; those who received concomitant fluoroscopic RUC were selected for the case series. Data collected included demographics, preoperative evaluation, surgical interventions, and outcomes. RUC images were individually examined and the anatomic impression compared to previous renal US and VCUG. Novel RUC findings not previously appreciated by the preoperative evaluation were noted. RUC was performed by cystoscopically inserting a needle into the ureterocele and injecting contrast retrograde. If indicated, simultaneous cystography was performed to visualize the bladder and ipsilateral refluxing ureter. RESULTS: Of 43 patients that underwent surgery for suspected ureterocele, 28 underwent cystoscopy + RUC (10M: 18F) at a median age of 4.6 months and median follow-up of 37.0 months. 21 had images available for review. All patients had prior u/s, 25 had prior VCUG, and 20 had prior radionuclide studies. Ureteroceles were either duplex system (n=21) or single system (n=7); 17 were ectopic into the bladder neck or urethra; 7 were intravesicular; 4 were pseudoureteroceles. 14 patients underwent concomitant transurethral ureterocele incision (TUIU); 2 were deferred for surgery; 11 received concomitant definitive surgery (e.g. nephrectomy). RUC illuminated novel aspects of the anatomy in 20 patients. No adverse events occurred. Notably, in 9 of 28 children, significant observations from RUC prompted change to the preoperative surgical plan. CONCLUSIONS: Intraoperative RUC further defines ureterocele anatomy in nearly all cases and yields changes to the original surgical plan with enough frequency to merit greater use in complex patients.