Paul J. Chang
University of Chicago
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Featured researches published by Paul J. Chang.
Journal of Digital Imaging | 2008
Matthew B. Morgan; Barton F. Branstetter; David M. Lionetti; Jeremy S. Richardson; Paul J. Chang
As radiology departments transition to near-complete digital information management, work flows and their supporting informatics infrastructure are becoming increasingly complex. Digital dashboards can integrate separate computerized information systems and summarize key work flow metrics in real time to facilitate informed decision making. A PACS-integrated digital dashboard function designed to alert radiologists to their unsigned report queue status, coupled with an actionable link to the report signing application, resulted in a 24% reduction in the time between transcription and report finalization. The dashboard was well received by radiologists who reported high usage for signing reports. Further research is needed to identify and evaluate other potentially useful work flow metrics for inclusion in a radiology clinical dashboard.
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 1998
David J Holtzmann; William T. Johnson; Thomas E. Southard; John A Khademi; Paul J. Chang; Eric M. Rivera
OBJECTIVES The purpose of this study was to compare D-speed film, E-speed film, and the Soredex Digora system with respect to the detection of periradicular pathosis. STUDY DESIGN Radiographic images of 100 cadaver jaws were made with E-speed film, D-speed film, and the Soredex Digora. Each set of 100 images was interpreted by four observers, with 30 days separating each of three viewing sessions from the next. The presence or absence of pathologic (inflammatory) periradicular bone resorption was determined by histologic examination of the samples. The observer performance was compared with the true histologic findings and evaluated with receiver operating characteristic and corrected receiver operating characteristic analysis. RESULTS No statistically significant differences were found in diagnostic performance among the three radiographic techniques. In addition, no imaging technique was a good indicator of pathosis as determined by histologic analysis. CONCLUSION Under the conditions of this study, it was determined that D-speed film, E-speed film, and the Soredex Digora were equivalent diagnostic imaging modalities with regard to the detection of pathologic periradicular bone resorption. No technique predictably indicated inflammatory resorption.
Radiographics | 2008
Alexander J. Towbin; Brian Paterson; Paul J. Chang
In the past decade, radiology has moved from being predominantly film based to predominantly digital. Although in clinical terms the transition has been relatively smooth, the method in which radiology is taught has not kept pace. Simulator programs have proved effective in other specialties as a method for teaching a specific skill set. Because many radiologists already work in the digital environment, a simulator could easily and safely be integrated with a picture archiving and communication system (PACS) and become a powerful tool for radiology education. Thus, a simulator program was designed for the specific purpose of giving residents practice in reading images independently, thereby helping them to prepare more fully for the rigors of being on call. The program is similar to a typical PACS, thus allowing a more interactive learning process, and closely mimics the real-world practice of radiology to help prepare the user for a variety of clinical scenarios. Besides education, other possible uses include certification, testing, and the creation of teaching files.
Cancer Discovery | 2018
Eirini Pectasides; Matthew D. Stachler; Sarah Derks; Yang Liu; Steven Brad Maron; Mirazul Islam; Lindsay Alpert; Heewon A. Kwak; Hedy L. Kindler; Blase N. Polite; Manish R. Sharma; Kenisha Allen; Emily O'Day; S Lomnicki; Melissa Maranto; Rajani Kanteti; Carrie Fitzpatrick; Christopher R. Weber; Namrata Setia; Shu-Yuan Xiao; John Hart; Rebecca J. Nagy; Kyoung-Mee Kim; Min-Gew Choi; Byung-Hoon Min; Katie S. Nason; Lea O'Keefe; Masayuki Watanabe; Hideo Baba; Rick Lanman
Gastroesophageal adenocarcinoma (GEA) is a lethal disease where targeted therapies, even when guided by genomic biomarkers, have had limited efficacy. A potential reason for the failure of such therapies is that genomic profiling results could commonly differ between the primary and metastatic tumors. To evaluate genomic heterogeneity, we sequenced paired primary GEA and synchronous metastatic lesions across multiple cohorts, finding extensive differences in genomic alterations, including discrepancies in potentially clinically relevant alterations. Multiregion sequencing showed significant discrepancy within the primary tumor (PT) and between the PT and disseminated disease, with oncogene amplification profiles commonly discordant. In addition, a pilot analysis of cell-free DNA (cfDNA) sequencing demonstrated the feasibility of detecting genomic amplifications not detected in PT sampling. Lastly, we profiled paired primary tumors, metastatic tumors, and cfDNA from patients enrolled in the personalized antibodies for GEA (PANGEA) trial of targeted therapies in GEA and found that genomic biomarkers were recurrently discrepant between the PT and untreated metastases. Divergent primary and metastatic tissue profiling led to treatment reassignment in 32% (9/28) of patients. In discordant primary and metastatic lesions, we found 87.5% concordance for targetable alterations in metastatic tissue and cfDNA, suggesting the potential for cfDNA profiling to enhance selection of therapy.Significance: We demonstrate frequent baseline heterogeneity in targetable genomic alterations in GEA, indicating that current tissue sampling practices for biomarker testing do not effectively guide precision medicine in this disease and that routine profiling of metastatic lesions and/or cfDNA should be systematically evaluated. Cancer Discov; 8(1); 37-48. ©2017 AACR.See related commentary by Sundar and Tan, p. 14See related article by Janjigian et al., p. 49This article is highlighted in the In This Issue feature, p. 1.
Cancer Epidemiology, Biomarkers & Prevention | 2015
Abhineet Uppal; Michael G. White; Sapna Nagar; Briseis Aschebrook-Kilfoy; Paul J. Chang; Peter Angelos; Edwin L. Kaplan; Raymon H. Grogan
Purpose: Thyroid nodules incidentally identified on imaging are thought to contribute to the increasing incidence of thyroid cancer. We aim to determine the true rate of incidental thyroid nodule reporting, malignancy rates of these nodules, and to compare these findings with rates of detection by dedicated radiology review. Methods: A cross-sectional analysis was done to determine the prevalence of thyroid nodules in radiologist reports by analyzing all reports for CT, PET, and MRI scans of the head, neck, and chest as well as neck ultrasounds performed at a tertiary care center from 2007 to 2012. Retrospective chart review was performed on patients with a reported thyroid nodule to determine clinical outcomes of these nodules. Radiology reports were compared with dedicated radiology review of 500 randomly selected CT scans from the study group to determine the difference between clinical reporting and actual prevalence of thyroid nodules. Results: 97,908 imaging studies met inclusion criteria, and 387 (0.4%) thyroid incidentalomas were identified on radiology report. One hundred and sixty three (42.1%) of these nodules were worked up with fine-needle aspiration, diagnosing 27 thyroid cancers (0.03% of all studies, 7.0% of reported incidentalomas). The prevalence of incidentalomas clinically reported was 142/100,000 CT scans, 638/100,000 MRIs, 358/100,000 PET scans, and 6,594/100,000 ultrasounds. In contrast, review of CT scans screening for thyroid nodules had a prevalence of 10%. Conclusion: Routine clinical reporting of incidental thyroid nodules is far less common than on dedicated review. Impact: These data contradict the notion that incidentalomas contribute significantly to rising thyroid cancer rates. Cancer Epidemiol Biomarkers Prev; 24(9); 1327–31. ©2015 AACR.
Journal of Digital Imaging | 2006
Matthew B. Morgan; Barton F. Branstetter; Jonathan Mates; Paul J. Chang
Radiology workflows have become more distributed and complicated, and fewer tangible cues are available to the radiologist to help optimize task prioritization and selection. Additionally, faster scanners, more detailed exams, and increased demand for imaging services have precipitated a potential image overload for todays radiologists who are pressured to provide efficient, quality service in less time. Radiologists are faced with the task of operating within complex systems but are lacking tools to efficiently and effectively monitor these systems in real time. Dashboard technology can help address this deficiency in radiology and facilitate informed, optimized decisions about workflow. Possible areas of application include workflow consolidation, workload distribution, and urgency evaluation. Dashboards should be optimized, context-sensitive, customizable, and workflow-integrated. Further research is needed to identify the most important dashboard metrics, determine their optimal display, and validate their utility.
Journal of Digital Imaging | 2014
Thusitha Dananjaya De Silva Mabotuwana; Michael C. Lee; Eric Cohen-Solal; Paul J. Chang
The naming of imaging procedures is currently not standardized across institutions. As a result, it is a challenge to establish national registries, for instance, a national registry of dose to facilitate comparisons among different types of CT procedures. RSNA’s RadLex Playbook is an effort towards addressing this gap (by introducing a unique Playbook identifier called an RPID for each procedure), and the current research focuses on semi-automatically mapping institution-specific procedure descriptions to Playbook entries to assist with this standardization effort. We discuss an algorithm we have developed to facilitate the mapping process which first extracts RadLex codes from the procedure description and then uses the definition of an RPID to determine the most suitable RPID(s) for the extracted set of RadLex codes. We also developed a tool that has three modes of operations—a single procedure mapping mode that allows a user to map a single institution-specific procedure description to a Playbook entry, a bulk mode to process large number of descriptions, and an exploratory mode that assists a user to better understand how the selection of values for various Playbook attributes affects the resulting RPID. We validate our algorithms using 166 production CT procedure descriptions and discuss how the tool can be used by administrators to map institution-specific procedure descriptions to RPIDs.
Journal of Digital Imaging | 2007
Jonathan Mates; Barton F. Branstetter; Matthew B. Morgan; David M. Lionetti; Paul J. Chang
Communication between clinicians, technologists, and radi ologists has become more complex, with Picture Archiving and Communication Systems (PACS) now allowing the radiologist to be removed from the physical location of the patients and the site of imaging. With these changes, effective communication becomes an ongoing challenge. Efficient communication of study interpretations has also become a priority for radiologists as they struggle to maintain relevance and provide added value to patient care when clinicians have ready access to radiology images. The purpose of this paper is to share our experience in developing and implementing the Collaborative Notification System (CNS), a communication tool used to inform referring clinicians of urgent findings—a.k.a. “wet reads.” The system utilizes a system of web pages integrated into PACS for the sending and receiving of succinct messages to provide clinical information at the point of need. A second system of pager alerts provides notification of the need for such communication through a relatively unintrusive, one-way, acknowledged alert system. The CNS provides asynchronous, integrated communication for the reporting of urgent and emergent radiology findings in a complex, geographically distributed medical environment.
Journal of Clinical Oncology | 2018
Jason J. Luke; Jeffrey Lemons; Theodore Karrison; Sean P. Pitroda; J.M. Melotek; Yuanyuan Zha; Hania A. Al-Hallaq; Ainhoa Arina; Nikolai N. Khodarev; Linda Janisch; Paul J. Chang; Jyoti D. Patel; Gini F. Fleming; John Moroney; Manish R. Sharma; Mark J. Ratain; Thomas F. Gajewski; Ralph R. Weichselbaum; Steven J. Chmura
Purpose Stereotactic body radiotherapy (SBRT) may stimulate innate and adaptive immunity to augment immunotherapy response. Multisite SBRT is an emerging paradigm for treating metastatic disease. Anti-PD-1-treatment outcomes may be improved with lower disease burden. In this context, we conducted a phase I study to evaluate the safety of pembrolizumab with multisite SBRT in patients with metastatic solid tumors. Patients and Methods Patients progressing on standard treatment received SBRT to two to four metastases. Not all metastases were targeted, and metastases > 65 mL were partially irradiated. SBRT dosing varied by site and ranged from 30 to 50 Gy in three to five fractions with predefined dose de-escalation if excess dose-limiting toxicities were observed. Pembrolizumab was initiated within 7 days after completion of SBRT. Pre- and post-SBRT biopsy specimens were analyzed in a subset of patients to quantify interferon-γ-induced gene expression. Results A total of 79 patients were enrolled; three patients did not receive any treatment and three patients only received SBRT. Patients included in the analysis were treated with SBRT and at least one cycle of pembrolizumab. Most (94.5%) of patients received SBRT to two metastases. Median follow-up for toxicity was 5.5 months (interquartile range, 3.3 to 8.1 months). Six patients experienced dose-limiting toxicities with no radiation dose reductions. In the 68 patients with imaging follow-up, the overall objective response rate was 13.2%. Median overall survival was 9.6 months (95% CI, 6.5 months to undetermined) and median progression-free survival was 3.1 months (95% CI, 2.9 to 3.4 months). Expression of interferon-γ-associated genes from post-SBRT tumor biopsy specimens significantly correlated with nonirradiated tumor response. Conclusion Multisite SBRT followed by pembrolizumab was well tolerated with acceptable toxicity. Additional studies exploring the clinical benefit and predictive biomarkers of combined multisite SBRT and PD-1-directed immunotherapy are warranted.
American Journal of Roentgenology | 2015
Merlijn Sevenster; Adam R. Travis; Rajiv Ganesh; Peng Liu; Ursula Kose; Joost Frederik Peters; Paul J. Chang
OBJECTIVE. Imaging provides evidence for the response to oncology treatment by the serial measurement of reference lesions. Unfortunately, the identification, comparison, measurement, and documentation of several reference lesions can be an inefficient process. We tested the hypothesis that optimized workflow orchestration and tight integration of a lesion tracking tool into the PACS and speech recognition system can result in improvements in oncologic lesion measurement efficiency. SUBJECTS AND METHODS. A lesion management tool tightly integrated into the PACS workflow was developed. We evaluated the effect of the use of the tool on measurement reporting time by means of a prospective time-motion study on 86 body CT examinations with 241 measureable oncologic lesions with four radiologists. RESULTS. Aggregated measurement reporting time per lesion was 11.64 seconds in standard workflow, 16.67 seconds if readers had to register measurements de novo, and 6.36 seconds for each subsequent follow-up study. Differences were statistically significant (p < 0.05) for each reader, except for one difference for one reader. CONCLUSION. Measurement reporting time can be reduced by using a PACS workflow-integrated lesion management tool, especially for patients with multiple follow-up examinations, reversing the onetime efficiency penalty at baseline registration.