Hanna M. Zafar

Effect of Acute or Repeated Stress on Behavior and Brain Norepinephrine System in Wistar-Kyoto (WKY) Rats

WKY rats develop more restraint-induced gastric ulcers and exhibit more depressive behavior compared to other rat strains. Exposure to novel stressors for 21 days exacerbates depressive behavior in WKY rats and alters beta-adrenoceptors (beta-ARs) and norepinephrine transporter (NET) sites in several limbic brain regions when compared to Sprague-Dawley rats. The present study examined whether these effects would be elaborated following an acute stressor and whether WKY rats would demonstrate adaptation after repeated stress. Rats were subjected to a 2-h supine restraint stress for either one or eight consecutive daily sessions. Open-field behavioral data were collected immediately after the daily stress sessions. Brains were sectioned for autoradiographic analysis of 125I-pindolol binding to beta-ARs and 3H-nisoxetine binding to NET sites in discrete brain regions. Acute 1-day stress resulted in a significant drop in body weight and an inhibition of behaviors in the open field. These effects were also sustained following 7 days of chronic restraint stress. In contrast, while acute stress had no effect on NET binding sites or beta-ARs, repeated stress decreased NET sites in the amygdala, hypothalamus, and locus coeruleus with little effect on beta-ARs in the brain regions examined.

Suspected extracolonic neoplasms detected on CT colonography: literature review and possible outcomes.

RATIONALE AND OBJECTIVES This study summarizes the literature on the detection of cancer among indeterminate extracolonic findings on computed tomographic (CT) colonography in five targeted organs. MATERIALS AND METHODS We searched PubMed for English-language literature published between January 1, 1994, and December 31, 2010. We describe extracolonic findings in the kidney, lung, liver, pancreas, and ovary suspect for malignancy as they are associated with high mortality. For each organ, we calculated the median prevalence, positive predictive value (PPV), and false positive rate of malignancy and a pooled false-positive rate across studies. RESULTS Of 91 publications initially identified, 24 were eligible for review. Indeterminate renal masses on CT colonography had 20.5% median PPV and low pooled false positive rate of 1.3% (95% confidence interval 0.6-2.0). In contrast, indeterminate masses of the lung, liver, pancreas, and ovary had low PPV (median values ranged from 0% to 3.8%). Indeterminate masses of the ovary resulted in the highest pooled false-positive rate of 2.2%. Results were similar in studies of both screening and nonscreening populations. We estimated the probability of false positive results through the detection of significant extracolonic findings as 46 per 1000 for men and 68 per 1000 for women. CONCLUSIONS Indeterminate renal masses newly detected on CT colonography have an estimated one in five chance of malignancy and therefore warrant further follow-up to provide a definitive diagnosis. Conversely, indeterminate masses of the lung, liver, pancreas, and ovary are associated with high false positive rates and merit more conservative clinical follow-up.

Vascularity Assessment of Thyroid Nodules by Quantitative Color Doppler Ultrasound

Our objective was to assess the role of quantitative Doppler vascularity in differentiating malignant and benign thyroid nodules. Color Doppler images of 100 nodules were analyzed for three metrics: vascular fraction area, mean flow velocity index and flow volume index in three regions (nodule center, nodule rim and surrounding parenchyma). Vascular fraction area and flow volume index were higher in malignant than benign nodules in both the central and rim regions, whereas flow velocity index was equivalent in both regions. Of the three vascularity metrics studied, the vascular fraction area of the central region was most effective in predicting malignancy, with a sensitivity of 0.90 ± 0.05, specificity of 0.88 ± 0.13, positive predictive value of 0.84 ± 0.14, negative predictive value of 0.92 ± 0.03 and accuracy of 0.89 ± 0.08. Quantitative Doppler vascularity of the nodule center yielded a high level of discrimination between benign and malignant nodules and, thus, has the greatest potential to contribute to gray-scale assessment of thyroid cancer.

Integrating Natural Language Processing and Machine Learning Algorithms to Categorize Oncologic Response in Radiology Reports

A significant volume of medical data remains unstructured. Natural language processing (NLP) and machine learning (ML) techniques have shown to successfully extract insights from radiology reports. However, the codependent effects of NLP and ML in this context have not been well-studied. Between April 1, 2015 and November 1, 2016, 9418 cross-sectional abdomen/pelvis CT and MR examinations containing our internal structured reporting element for cancer were separated into four categories: Progression, Stable Disease, Improvement, or No Cancer. We combined each of three NLP techniques with five ML algorithms to predict the assigned label using the unstructured report text and compared the performance of each combination. The three NLP algorithms included term frequency-inverse document frequency (TF-IDF), term frequency weighting (TF), and 16-bit feature hashing. The ML algorithms included logistic regression (LR), random decision forest (RDF), one-vs-all support vector machine (SVM), one-vs-all Bayes point machine (BPM), and fully connected neural network (NN). The best-performing NLP model consisted of tokenized unigrams and bigrams with TF-IDF. Increasing N-gram length yielded little to no added benefit for most ML algorithms. With all parameters optimized, SVM had the best performance on the test dataset, with 90.6 average accuracy and F score of 0.813. The interplay between ML and NLP algorithms and their effect on interpretation accuracy is complex. The best accuracy is achieved when both algorithms are optimized concurrently.

Adverse events Following Computed Tomographic Colonography compared to Optical Colonoscopy in the Elderly.

Objective To evaluate gastrointestinal and cardiovascular adverse event risks associated with optical colonoscopy (OC) among Medicare outpatients who received computed tomography colonography (CTC) as their initial method of colorectal evaluation. Methods Medicare claims were compared between 6114 outpatients ≥ 66 years who received initial CTC and 149,202 outpatients who received initial OC between January 2007 and December 2008. OC patients were matched on county of residence and year of evaluation. Outcomes included lower gastrointestinal bleeding, gastrointestinal perforation, other gastrointestinal events and cardiovascular events resulting in an emergency department visit or hospitalization within 30 days. Results Among 1000 outpatients undergoing initial CTC, 12.4 experienced lower gastrointestinal bleeding, 0.7 perforation, 18.0 other gastrointestinal events and 45.5 cardiovascular events within 30 days. After multivariate adjustment, risks of lower gastrointestinal bleeding, other gastrointestinal events and cardiovascular events were higher with initial OC than CTC, with or without subsequent OC (Odds Ratio 1.91 95 Confidence Interval [1.47,2.49], Odds Ratio 1.35 95 Confidence Interval [1.07,1.69] and Odds Ratio 1.38 95 Confidence Interval [1.18,1.62], respectively); however, perforation risk did not differ (p = 0.10). This pattern is similar in older and symptomatic populations. Conclusion Rates of gastrointestinal bleeding, other gastrointestinal events and cardiovascular events are lower following initial CTC than OC, but rates of perforation do not differ.

Associations between Cancer-Related Information Seeking and Receiving PET Imaging for Routine Cancer Surveillance—An Analysis of Longitudinal Survey Data

Background: Routine cancer surveillance with positron emission tomography (PET) is not recommended for most patients who have completed curative treatment for cancer. Yet, recent trends suggest that PET is increasingly used for follow-up among patients with cancer. This study investigates whether information-seeking behaviors predicted self-reported utilization of PET for routine surveillance in patients with colorectal, breast, and prostate cancer. Methods: We conducted annual surveys for 3 years in a cohort of Pennsylvania cancer survivors diagnosed with colorectal, breast, or prostate cancer in 2005. The outcome was self-reported PET receipt for routine surveillance among 944 patients diagnosed with nonmetastatic disease (stages 0–III). Predictors included cancer-related information seeking from nonmedical sources and providers. Weighted multiple logistic regression analyses were performed. Results: In this population, 11% of patients reported receiving at least one PET scan for routine follow-up in a 12-month period several years after diagnosis. Seeking cancer-related information from nonmedical sources was associated with higher odds of subsequent reported PET use [OR, 3.7; 95% confidence interval (CI), 1.1–12.1; P = 0.032], after adjusting for potential confounders. Patient engagement with physicians about cancer-related information was not a significant predictor. Conclusions: Overall reported PET utilization for routine surveillance of colorectal, breast, and prostate cancer is low. However, we found a significant association with information seeking from nonmedical sources but not from providers. Impact: Exposure to cancer-related information through mass media and lay interpersonal sources may be driving inappropriate utilization of high-cost advanced imaging procedures. These findings have important implications for cancer survivors, healthcare providers, and health policy. Cancer Epidemiol Biomarkers Prev; 23(3); 481–9. ©2014 AACR.

Developing an Automated Database for Monitoring Ultrasound- and Computed Tomography-Guided Procedure Complications and Diagnostic Yield

Monitoring complications and diagnostic yield for image-guided procedures is an important component of maintaining high quality patient care promoted by professional societies in radiology and accreditation organizations such as the American College of Radiology (ACR) and Joint Commission. These outcome metrics can be used as part of a comprehensive quality assurance/quality improvement program to reduce variation in clinical practice, provide opportunities to engage in practice quality improvement, and contribute to developing national benchmarks and standards. The purpose of this article is to describe the development and successful implementation of an automated web-based software application to monitor procedural outcomes for US- and CT-guided procedures in an academic radiology department. The open source tools PHP: Hypertext Preprocessor (PHP) and MySQL were used to extract relevant procedural information from the Radiology Information System (RIS), auto-populate the procedure log database, and develop a user interface that generates real-time reports of complication rates and diagnostic yield by site and by operator. Utilizing structured radiology report templates resulted in significantly improved accuracy of information auto-populated from radiology reports, as well as greater compliance with manual data entry. An automated web-based procedure log database is an effective tool to reliably track complication rates and diagnostic yield for US- and CT-guided procedures performed in a radiology department.

Comparison of small bowel follow through and abdominal CT for detecting recurrent Crohn's disease in neoterminal ileum

PURPOSE To assess the findings of recurrent Crohns disease in the neoterminal ileum on small bowel follow through (SBFT) and computed tomography (CT) as well as the overall diagnostic performance of these imaging tests. METHODS Our radiology database yielded 52 patients with an ileocolic anastomosis for Crohns disease who underwent SBFT and CT. The images were reviewed to determine the sensitivity, specificity, PPV, and NPV for individual findings of recurrent Crohns disease in the neoterminal ileum. The overall sensitivity, specificity, PPV, and NPV of these tests for recurrent Crohns disease were determined by comparing imaging reports to endoscopic and surgical findings in 45 patients (87%) and clinical response to treatment in seven (13%). RESULTS SBFT had a sensitivity of 90%, specificity of 85%, PPV of 95%, and NPV of 73% for detecting recurrent Crohns disease, and CT had a sensitivity of 77%, specificity of 69%, PPV of 88%, and NPV of 50%. These tests combined had a sensitivity of 95%, specificity of 69%, PPV of 90%, and NPV of 82%. The most common findings were luminal narrowing, thickened folds, and ulcers (especially aphthoid lesions) on SBFT and bowel wall thickening on CT. CT also revealed extraenteric collections not visualized on SBFT in three patients (8%). CONCLUSIONS Our experience suggests that SBFT is more sensitive and specific than CT for detecting recurrent Crohns disease in the neoterminal ileum, mainly because of the ability of barium studies to depict aphthoid lesions not visualized on CT. Conversely, CT is better for detecting extraenteric findings such as abscesses. When combined, these tests have a higher sensitivity for detecting recurrent Crohns disease than either test alone.

Development of Automated Detection of Radiology Reports Citing Adrenal Findings

The aim of this study was to determine the feasibility of automated detection of adrenal nodules, a common finding on CT, using a newly developed search engine that mines dictated radiology reports. To ensure Health Insurance Portability and Accountability Act compliance, we utilized a preexisting de-identified database of 32,974 CT reports from February 1, 2009 to February 28, 2010. Common adrenal descriptors from 29 staff radiologists were used to develop an automated rule-based algorithm targeting adrenal findings. Each sentence within the free text of reports was searched with an adapted NegEx negation algorithm. The algorithm was refined using a 2-week test period of reports and subsequently validated using a 6-week period. Manual review of the 3,693 CT reports in the validation period identified 222 positive reports while the algorithm detected 238 positive reports. The algorithm identified one true positive report missed on manual review for a total of 223 true positive reports. This resulted in a precision of 91% (217 of 238) and a recall of 97% (217 of 223). The sensitivity of the query was 97.3% (95% confidence interval (CI), 93.9–98.9%), and the specificity was 99.3% (95% CI, 99.1–99.6%). The positive predictive value of the algorithm was 91.0% (95% CI, 86.6–94.3%), and the negative predictive value was 99.8% (95% CI, 99.6–99.9%). The prevalence of true positive adrenal findings identified by the query (7.1%) was nearly identical to the true prevalence (7.2%). Automated detection of language describing common findings in imaging reports, such as adrenal nodules on CT, is feasible.

Cost Differences After Initial CT Colonography Versus Optical Colonoscopy in the Elderly.

RATIONALE AND OBJECTIVES To compare differences in Medicare costs 1 year after initial computed tomographic colonography (CTC) or initial optical colonoscopy (OC). MATERIALS AND METHODS We performed a retrospective cohort study of asymptomatic Medicare outpatients aged ≥ 66 years who received initial CTC (n = 531) or OC (n = 17,593) between January 2007 and December 2008; initial OC patients were matched on county of residence and year of screening. Outcomes included differences in total inpatient and outpatient Medicare costs 1 year after initial CTC or OC and differences in outpatient testing of potential findings in the colon, abdomen, pelvis, and lungs. RESULTS Higher adjusted costs per patient were revealed in the year after initial CTC compared to initial OC for outpatient testing related to potential colonic (