Radiology Commons^™

Comparison Of Quantitative Analysis To Qualitative Analysis For Interpretation Of Lower Limb Lymphoscintigraphy, Edward Chege Nganga

Master of Medicine in Imaging and Diagnostic Radiology

Background: Lymphoscintigraphy is now the primary imaging modality used in determining a diagnosis in patients with suspected extremity lymphedema. However, analysis is mainly by visual qualitative analysis which is subjective and has a wide inter-observer variability. Subtle differences in ilioinguinal uptake between normal and abnormal limbs may be missed with visual qualitative analysis. This study seeks to compare quantitative analysis to qualitative analysis by computing percentage ilioinguinal nodes uptake at 1.5 hours. Objectives: To compare quantitative analysis to qualitative analysis of lower limb lymphoscintigraphy in the diagnosis of lymphedema. To determine the diagnostic accuracy of quantitative lymphoscintigraphy analysis. Methodology: 52 …

Characterization Of Low Density Intracranial Lesions Using Dual-Energy Computed To Mography, Jessica L. Nute

Dissertations and Theses (Open Access)

Calcific and hemorrhagic foci of susceptibility are frequently encountered on routine brain MR studies. Both etiologies cause variations in local magnetic field strength, leading to dark regions on the MR images that cannot be classified. Single-energy CT (SECT) can be used to identify lesions with attenuation over 100 HU as calcific, however lesions with lower attenuation cannot be reliably identified. While calcific lesions are unlikely to cause harm, hemorrhagic lesions carry a risk of subsequent intracranial bleeding; as such, identification of hemorrhage is vital in preventing the inappropriate use of anticoagulant medications in patients with hemorrhagic lesions.

Given there currently …

Re-Expansion Pulmonary Edema, Talal Alzahrani, Nawaf Abaalkhail, Mayssam Nehme, Jalil Ahari

GW Research Days 2015

Re-expansion pulmonary edema (RPE) is a rare complication of therapeutic thoracentesis. Unfortunately, there is no definitive treatment modality for RPE. The high mortality rate, reported up to 21%, presses the issue for finding adequate prevention and treatment. Here we report a new management modality that is very useful for a patient with RPE.

Case Report: An 80-year-old man with a history of hypertension, atrial fibrillation, congestive heart failure with preserved ejection fraction, and sacral decubitus ulcer, who was admitted for surgical debridement of his ulcer. He developed hospital-acquired pneumonia and was resolved with antibiotics and aggressive hydration. He became hypoxic, …

Image Enhancement Of Cancerous Tissue In Mammography Images, Richard Thomas Richardson

CCAC Theses and Dissertations

This research presents a framework for enhancing and analyzing time-sequenced mammographic images for detection of cancerous tissue, specifically designed to assist radiologists and physicians with the detection of breast cancer. By using computer aided diagnosis (CAD) systems as a tool to help in the detection of breast cancer in computed tomography (CT) mammography images, previous CT mammography images will enhance the interpretation of the next series of images. The first stage of this dissertation applies image subtraction to images from the same patient over time. Image types are defined as temporal subtraction, dual-energy subtraction, and Digital Database for Screening Mammography …

Knee Morphometric Risk Factors For Acute Anterior Cruciate Ligament Injury In Skeletally Immature Patients, Kenneth Aaron Shaw, Brian S. Dunoski, Neil J. Mardis, Donna M. Pacicca

Manuscripts, Articles, Book Chapters and Other Papers

© 2015, The Author(s).

Study design: Retrospective, case–control.

Purpose: Knee morphometric risk factors for noncontact anterior cruciate ligament (ACL) injury have been a popular topic with skeletally mature patients. Little research has focused on the skeletally immature, with conflicting conclusions. This study performs a comprehensive analysis of identified parameters thought to predispose to ACL injury in a skeletally immature cohort.

Methods: A retrospective review of pediatric patients undergoing knee magnetic resonance imaging (MRI) was performed over a 4-year period. Inclusionary criteria included mid-substance ACL disruption, skeletal immaturity, noncontact injury, without associated ligamentous disruption, and no medical condition associated with ligamentous …

Focused Ultrasound For Treatment Of Bone Tumours., Dario B. Rodrigues, Paul R. Stauffer, David Vrba, Mark Hurwitz, Md

Department of Radiation Oncology Faculty Papers

PURPOSE: Focused ultrasound (FUS) is a modality with rapidly expanding applications across the field of medicine. Treatment of bone lesions with FUS including both benign and malignant tumours has been an active area of investigation. Recently, as a result of a successful phase III trial, magnetic resonance-guided FUS is now a standardised option for treatment of painful bone metastases. This report reviews the clinical applications amenable to treatment with FUS and provides background on FUS and image guidance techniques, results of clinical studies, and future directions.

METHODS: A comprehensive literature search and review of abstracts presented at the recently completed …

Cost-Effectiveness Of Coronary Artery Calcium Testing For Coronary Heart And Cardiovascular Disease Risk Prediction To Guide Statin Allocation: The Multi-Ethnic Study Of Atherosclerosis (Mesa), Khurram Nasir

All Publications

BACKGROUND: The Multi-Ethnic Study of Atherosclerosis (MESA) showed that the addition of coronary artery calcium (CAC) to traditional risk factors improves risk classification, particularly in intermediate risk asymptomatic patients with LDL cholesterol levels /dL. However, the cost-effectiveness of incorporating CAC into treatment decision rules has yet to be clearly delineated.OBJECTIVE: To model the cost-effectiveness of CAC for cardiovascular risk stratification in asymptomatic, intermediate risk patients not taking a statin. Treatment based on CAC was compared to (1) treatment of all intermediate-risk patients, and (2) treatment on the basis of United States guidelines.METHODS: We developed a Markov model of first coronary …

Nasolacrimal System Aeration On Computed Tomographic Imaging: Effects Of Patient Positioning And Scan Orientation., Craig N Czyz, Thomas S Bacon, Andrew W Stacey, Eva N Cahill, Bryan R Costin, Boris I Karanfilov, Kenneth V Cahill

Ambulatory and Primary Care Articles

PURPOSE: To determine the impact of patient positioning and scan orientation on the appearance of air in the nasolacrimal drainage system on computed tomography (CT) imaging, and the repeatability of the observations.

METHODS: This was a retrospective analysis of CT images for 92 patients.

RESULTS: Air was found to be present more fully in the upright-position group as compared with the supine-position group. Comparing axial and coronal scan orientation, no difference in aeration was found, except for the nasolacrimal duct in the upright-position group.

CONCLUSION: Patient position should be accounted for in diagnostic conclusions and treatment decisions based on CT.

Is Metabolic Syndrome Predictive Of Prevalence, Extent, And Risk Of Coronary Artery Disease Beyond Its Components? Results From The Multinational Coronary Ct Angiography Evaluation For Clinical Outcome: An International Multicenter Registry (Confirm), Ricardo Cury

All Publications

No abstract provided.

Labrad : Vol 41, Issue 1 - March 2015, Aga Khan University Hospital, Karachi

LABRAD - Departments of Pathology & Laboratory Medicine and Radiology Archives

• An Overview of Proficiency Testing
• Sources of Pre-analytical Variations
• Five Q-Framework for Implementing Total Quality Management in Laboratory
• Delta Check in Clinical Laboratory
• Indicators of Quality Improvement in Surgical Pathology
• Types of Analytical Errors
• Method Validation for Quantitative Tests: CAP Recommendations
• Levey Jenning Chart and a Guide to Use Westgard Rules
• Quality Control of Vitek-2 System
• Establishing Quality Control Values for Haematology Parameters

Radiation Therapy After Radical Prostatectomy For Prostate Cancer: Evaluation Of Complications And Influence Of Radiation Timing On Outcomes In A Large, Population-Based Cohort., Sarah E Hegarty, Terry Hyslop, Adam Dicker Md, Phd, Timothy Showalter Md

Department of Radiation Oncology Faculty Papers

PURPOSE: To evaluate the influence of timing of salvage and adjuvant radiation therapy on outcomes after prostatectomy for prostate cancer.

METHODS: Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified prostate cancer patients diagnosed during 1995-2007 who had one or more adverse pathological features after prostatectomy. The final cohort of 6,137 eligible patients included men who received prostatectomy alone (n = 4,509) or with adjuvant (n = 894) or salvage (n = 734) radiation therapy. Primary outcomes were genitourinary, gastrointestinal, and erectile dysfunction events and survival after treatment(s).

RESULTS: Radiation therapy after prostatectomy was associated with higher rates …

Active Brain Regions During Sleep Using Electroencephalography-Functional Magnetic Resonance Imaging, Grace Duan '15, Sameeksha Malhotra '15, Todd B. Parrish

Student Publications & Research

Purpose: To determine the differences in functional connectivity among brain regions during the different stages of the human sleep cycle.

The Artificial Divide Between Biomedical Sciences And Clinical Medicine In Undergraduate Medical Education, Abdul Rehman, Noor Ul-Ain Baloch, Muhammad Awais

Department of Biological & Biomedical Sciences

No abstract provided.

African American Men With Low-Grade Prostate Cancer Have Increased Disease Recurrence After Prostatectomy Compared With Caucasian Men., Kosj Yamoah, Curtiland Deville, Neha Vapiwala, Elaine Spangler, Charnita M. Zeigler-Johnson, Bruce Malkowicz, David I Lee, Michael Kattan, Adam P. Dicker, Timothy R. Rebbeck

Department of Radiation Oncology Faculty Papers

PURPOSE: To explore whether disparities in outcomes exist between African American (AA) and Caucasian (CS) men with low-grade prostate cancer and similar cancer of the prostate risk assessment-postsurgery (CAPRA-S) features following prostatectomy (RP).

METHODS: The overall cohort consisted of 1,265 men (234 AA and 1,031 CS) who met the National comprehensive cancer network criteria for low- to intermediate-risk prostate cancer and underwent RP between 1990 and 2012. We first evaluated whether clinical factors were associated with adverse pathologic outcomes and freedom from biochemical failure (FFbF) using the entire cohort. Next, we studied a subset of 705 men (112 AA and …

On Voxel-By-Voxel Accumulated Dose For Prostate Radiation Therapy Using Deformable Image Registration., Jialu Yu, Nicholas Hardcastle, Kyoungkeun Jeong, Edward T. Bender, Mark A. Ritter, Wolfgang A. Tomé

Department of Radiation Oncology Faculty Papers

Since delivered dose is rarely the same with planned, we calculated the delivered total dose to ten prostate radiotherapy patients treated with rectal balloons using deformable dose accumulation (DDA) and compared it with the planned dose. The patients were treated with TomoTherapy using two rectal balloon designs: five patients had the Radiadyne balloon (balloon A), and five patients had the EZ-EM balloon (balloon B). Prostate and rectal wall contours were outlined on each pre-treatment MVCT for all patients. Delivered fractional doses were calculated using the MVCT taken immediately prior to delivery. Dose grids were accumulated to the last MVCT using …

Inhibitory Behavioral Control: A Stochastic Dynamic Causal Modeling Study Comparing Cocaine Dependent Subjects And Controls, Liangsuo Ma, Joel L. Steinberg, Kathryn A. Cunningham, Scott D. Lane, James M. Bjork, Harshini Neelakantan, Amanda E. Price, Ponnada A. Narayana, Thomas R. Kosten, Antoine Bechara, F. Gerard Moeller

Radiology Publications

Cocaine dependence is associated with increased impulsivity in humans. Both cocaine dependence and impulsive behavior are under the regulatory control of cortico-striatal networks. One behavioral laboratory measure of impulsivity is response inhibition (ability to withhold a prepotent response) in which altered patterns of regional brain activation during executive tasks in service of normal performance are frequently found in cocaine dependent (CD) subjects studied with functional magnetic resonance imaging (fMRI). However, little is known about aberrations in specific directional neuronal connectivity in CD subjects. The present study employed fMRI-based dynamic causal modeling (DCM) to study the effective (directional) neuronal connectivity associated …

Evaluating Ct Perfusion Deficits In Global Cerebral Edema After Aneurysmal Subarachnoid Hemorrhage, H. Baradaran, V. Fodera, D. Mir, K. Kesavobhotla, J. Ivanidze, U. Ozbek, A. Gupta, J. Claassen, P. C. Sanelli

Journal Articles

BACKGROUND AND PURPOSE: Global cerebral edema is an independent predictor of mortality and poor outcomes after aneurysmal SAH. Global cerebral edema, a complex disease process, is thought to be associated with an altered cerebral autoregulatory response. We studied the association between cerebral hemodynamics and early global cerebral edema by using CTP. MATERIALS AND METHODS: We retrospectively studied consecutive patients with aneurysmal SAH with admission CTP performed at days 0-3. Two neuroradiologists classified global cerebral edema and hydrocephalus on NCCT performed concurrently with CTP. Global cerebral edema was defined as diffuse effacement of the sulci and/or basal cisterns or diffuse disruption …

Sparsity Techniques In Medical Imaging, R. Fang, T. Chen, D. Metaxas, P. Sanelli, S. Zhang

Journal Articles

No abstract provided.

Effect Of Reconstruction Algorithms On The Accuracy Of (99m)Tc Sestamibi Spect/Ct Parathyroid Imaging, K. J. Nichols, G. G. Tronco, C. J. Palestro

Journal Articles

The superiority of SPECT/CT over SPECT for (99m)Tc-sestamibi parathyroid imaging often is assumed to be due to improved lesion localization provided by the anatomic component (computed tomography) of the examination. It also is possible that this superiority may be related to the algorithms used for SPECT data reconstruction. The objective of this investigation was to determine the effect of SPECT reconstruction algorithms on the accuracy of MIBI SPECT/CT parathyroid imaging. We retrospectively analyzed preoperative MIBI SPECT/CT parathyroid imaging studies performed on 106 patients. SPECT data were reconstructed by filtered back projection (FBP) and by iterative reconstruction with corrections for collimator …

Carotid Artery Stenosis: Cost-Effectiveness Of Assessment Of Cerebrovascular Reserve To Guide Treatment Of Asymptomatic Patients, A. Pandya, A. Gupta, H. Kamel, B. B. Navi, P. C. Sanelli, B. R. Schackman

Journal Articles

PURPOSE: To project and compare the lifetime health benefits, health care costs, and incremental cost-effectiveness of a decision rule based on assessment of cerebrovascular reserve (CVR) compared with medical therapy and immediate revascularization in asymptomatic patients with carotid artery stenosis for prevention of stroke. MATERIALS AND METHODS: The three strategies compared included immediate revascularization (carotid endarterectomy) and ongoing medical therapy (with antiplatelet, statin, and antihypertensive agents plus lifestyle modification), medical therapy-based treatment with revascularization only for patients who progressed, and use of a CVR-based decision rule for treatment in which patients with CVR impairment undergo immediate revascularization and all others …