Medical Specialties Commons^™

Shape/Image Registration For Medical Imaging : Novel Algorithms And Applications., Ahmed Magdy Shalaby 1982-

Electronic Theses and Dissertations

This dissertation looks at two different categories of the registration approaches: Shape registration, and Image registration. It also considers the applications of these approaches into the medical imaging field. Shape registration is an important problem in computer vision, computer graphics and medical imaging. It has been handled in different manners in many applications like shapebased segmentation, shape recognition, and tracking. Image registration is the process of overlaying two or more images of the same scene taken at different times, from different viewpoints, and/or by different sensors. Many image processing applications like remote sensing, fusion of medical images, and computer-aided surgery …

Hyperthermia, Radiation And Chemotherapy: The Role Of Heat In Multidisciplinary Cancer Care., Mark Hurwitz, Md, Paul R. Stauffer

Department of Radiation Oncology Faculty Papers

The compelling biologic basis for combining hyperthermia with modern cancer therapies including radiation and chemotherapy was first appreciated nearly half a century ago. Hyperthermia complements radiation as conditions contributing to radio-resistance generally enhance sensitivity to heat and sensitizing effects occur through increased perfusion/tumor oxygenation and alteration of cellular death pathways. Chemosensitization with hyperthermia is dependent on the particular mechanism of effect for each agent with synergistic effects noted for several commonly used agents. Clinically, randomized trials have demonstrated benefit including survival with the addition of hyperthermia to radiation or chemotherapy in treatment of a wide range of malignancies. Improvements in …

Treatment Updates Regarding Anaplastic Oligodendroglioma And Anaplastic Oligoastrocytoma, Khurshid Ahmed Khan, Ahmed Nadeem Abbasi, Nasir Ali

Department of Radiation Oncology

Anaplastic Oligodendroglioma / Anaplastic Oligoastrocytoma (AO/AOA) is a WHO Grade-III primary brain tumor. These tumors comprise about 5 - 10% of all gliomas, which make them the third most common primary brain tumors after glioblastoma multiforme and astrocytomas. For many years standard of treatment remained Maximum Safe Resection (MSR) followed by Radiotherapy (RT). These tumors have also been known to be sensitive to alkylator-based chemotherapy particularly the subset having 1p/19q co-deletion signature. There is robust data showing that these tumors are responsive to chemotherapy in recurrent or progressive setting. Recently, up front chemotherapy has been added to standard post-surgery RT. …

Labrad : Vol 40, Issue 2 - November 2014, Aga Khan University Hospital, Karachi

LABRAD - Departments of Pathology & Laboratory Medicine and Radiology Archives

• Significance of HLA Typing in Transplant Medicine
• Role of Protocol Renal Biopsies in Transplant Patients
• Blood Product Utilization in Haematopoietic Stem Cell Transplant Recipients
• Use of Magic Marker “C4d” in the Diagnosis of Acute Antibody Mediated Rejection in Renal Transplant Patients
• Coagulopathy in Renal Transplantation
• Therapeutic Drug Monitoring of Cyclosporine
• Signifi cance of CMV antigenemia Assay In Renal Transplant Patients
• Pretransplant Serological Evaluation
• Importance of Monitoring Cytomegalovirus (CMV) and BKV (Polyomavirus) Infection in Renal Transplant Patients

A Unique Mri Presentation Of Fungal Infection In The Brain, Muhammad Bilal Salman Khan, Saad Shafqat, Ather Enam

Section of Neurology

Fungal infections of CNS are common in certain geographic locations. MRI with or without contrast is a useful prediagnostic tool. However, the findings may sometimes be misleading. In this case report, the authors present unusual imaging findings in the MRI of fungal infection in an immunocompetent host, whereby hyper-intense signals were seen on T2-weighted images and patchy post-contrast enhancement was observed with surrounding edema. These findings were suggestive of a neoplastic lesion but it was identified as aspergillosis on subsequent histopathology. This unusual MRI finding of CNS highlights the need to consider fungal infection as a differential diagnosis of all …

Teamstepps: Radiologic Sciences Students’ Perspective, Sandra Freed, Amanda Lafontaine, Daniel Roberts, Allison Urbaniak, Collleen Dempsey, Ms, Rt (R)

Department of Radiologic Sciences Faculty Papers

Introduction

Interprofessional education aims to improve the health care system by encouraging healthcare professionals to learn from, with and about each other.

Interprofessional education activities assist in breaking the barriers between the various disciplines in our healthcare system. Students and employees can benefit from interprofessional education and training.

Magnetic Resonance Spectroscopy Of Enhancing Cerebral Lesions: Analysis Of 78 Histopathology Proven Cases, Muhammad Shahbaz Alam, Humera Ahsan, Zafar Sajjad, Madiha Beg, Umer Bhatti, Ather Enam, Mohammad Wasay

Department of Radiology

Objectives: To investigate the efficacy of magnetic resonance spectroscopy in differentiating various types of neoplastic and non-neoplastic enhancing cerebral lesions.
Methods: The prospective study was conducted from January 2007 to December 2009 at the Department of Radiology, Aga Khan University Hospital, Karachi. All patients with enhancing brain lesions on magnetic resonance imaging who underwent magnetic resonance spectroscopy and a biopsy with histopathological analysis were included in study. The lesions were categorised into neoplastic and non-neoplastic lesions on the basis of spectroscopy findings. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of magnetic resonance spectroscopy were calculated. …

Case 213, John J. Krol, Vera V. Krol, Adrian Dawkins, Halemane S. Ganesh

Radiology Faculty Publications

No abstract provided.

Pharyngeal And Cervical Cancer Incidences Significantly Correlate With Personal Uv Doses Among Whites In The United States, Dianne E. Godar, Rong Tang, Stephen Merrill

Mathematics, Statistics and Computer Science Faculty Research and Publications

Because we found UV-exposed oral tissue cells have reduced DNA repair and apoptotic cell death compared with skin tissue cells, we asked if a correlation existed between personal UV dose and the incidences of oral and pharyngeal cancer in the United States. We analyzed the International Agency for Research on Cancer's incidence data for oral and pharyngeal cancers by race (white and black) and sex using each state's average annual personal UV dose. We refer to our data as ‘white’ rather than ‘Caucasian,’ which is a specific subgroup of whites, and ‘black’ rather than African-American because blacks from other countries …

Sensitivity Of Mri-Guided Near-Infrared Spectroscopy Clinical Breast Exam Data And Its Impact On Diagnostic Performance, Michael A. Mastanduno, Junqing Xu, Fadi El-Ghussein, Shudong Jiang, Hong Yin, Yan Zhao, Kelly E. Michaelson, Ke Wang, Fang Ren, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

In this study, data from breast MRI-guided near infrared spectroscopy (NIRS) exams delivered to 44 patients scheduled for surgical resection (ending in 16 benign and 28 malignant diagnoses) were analyzed using a spatial sensitivity metric to quantify the adequacy of the optical measurements for interrogating the tumor region of interest, as derived from the concurrent MRI scan. Along with positional sensitivity, the incorporation of spectral priors and the selection of an appropriate regularization parameter in the image reconstruction were considered, and found to influence the diagnostic accuracy of the recovered images. Once optimized, the MRI/NIRS data was able to differentiate …

The Role Of Inflammation In Contrast-Induced Nephropathy, Elijah Kwasa, Sudhir Vinayak, Robert Armstrong

Imaging & Diagnostic Radiology, East Africa

Objective: Global incidence of contrast-induced nephropathy (CIN) is 2-5%, but a recent Kenyan study highlighted a local incidence of 12-14% without offering an explanation for the higher incidence. This study proposes that inflammatory states confer a higher relative risk for development of CIN. Our objective was to determine the risk of developing CIN given the presence of an inflammatory state in patients in Kenya.

Methods: Prospective cohort study of patients undergoing a contrast-enhanced CT (CECT) scan in a private university teaching hospital in Kenya and having no known risk factors for CIN. 423 patients were recruited and grouped into those …

Of Predatory Publishers And Spurious Impact Factors, Saba Sohail

Department of Radiology

No abstract provided.

An Evaluation Of Mammography Rates For Women, 50-74 Years Old, At The San Francisco Department Of Public Health, Kimberly Litts

Master's Projects and Capstones

This paper explores the efforts of the San Francisco Department of Public Health (SFDPH) and San Francisco General Hospital (SFGH) to increase their overall mammogram screening rate to 76.7% by June 2015 in order to receive funding from the federal government. The target population is women within SF DPH’s primary care program, 50-74 years old, and overdue for a mammogram.

The literature reports there are health disparities among women who receive mammograms and how breast cancer affects them. African American women have the highest mortality rates and women of color are more likely to be diagnosed at a later stage, …

Variability In Eit Images Of Lung Ventilation As A Function Of Electrode Planes And Body Positions, Jie Zhang, Robert Patterson

Radiology Faculty Publications

This study is aimed at investigating the variability in resistivity changes in the lung region as a function of air volume, electrode plane and body position. Six normal subjects (33.8 ± 4.7 years, range from 26 to 37 years) were studied using the Sheffield Electrical Impedance Tomography (EIT) portable system. Three transverse planes at the level of second intercostal space, the level of the xiphisternal joint, and midway between upper and lower locations were chosen for measurements. For each plane, sixteen electrodes were uniformly positioned around the thorax. Data were collected with the breath held at end expiration and after …

Higher Event Rate In Patients With Known Cad Despite A Normal Myocardial Perfusion Scan, Maseeh Uz Zaman, Nosheen Fatima

Department of Radiology

Abstract

OBJECTIVE:

The negative predictive value of a normal single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is very high. However, prognostic implication of a normal SPECT MPI in patients with known coronary artery disease (CAD) is not clear. Objective of this study was to evaluate the cardiac event rate in patients with known CAD who had a normal stress SPECT MPI.

METHODS:

This prospective study accrued 428 consecutive patients with a history of CAD [revascularization or previous myocardial infarction (MI)] who had a normal stress (dynamic exercise or dipyridamole intervention) and rest Tc-99m-MIBI SPECT MPI. These patients were …

Vincristine-Induced Vocal Cord Palsy And Successful Re-Treatment In A Patient With Diffuse Large B Cell Lymphoma: A Case Report, Zarka Samoon, Munira Shabbir-Moosajee

Department of Radiation Oncology

Background: Vincristine, a type of vinca alkaloid, is widely used in the treatment of various childhood and adult malignancies. A well-known side effect of vincristine is its neurotoxicity and it is rarely indicted in vagus nerve involvement. Vincristine induced vocal cord palsy is a potentially reversible condition, with the mainstay of therapy being withdrawal of the offending drug. However, there are no clear guidelines regarding the possibility of re-treatment with the causative agent.CASE PRESENTATION: A 58 year old Asian male presented with constipation and abdominal distension. Diagnostic investigations revealed stage IVB diffuse large B cell lymphoma (DLBCL). The patient was …

The Potential Role Of Magnetic Resonance Spectroscopy In Image-Guided Radiotherapy., Mai Lin Nguyen, Brooke Willows, Rihan Khan, Alexander Chi, Lyndon Kim, Sherif G Nour, Thomas Sroka, Christine Kerr, Juan Godinez, Melissa Mills, Ulf Karlsson, Gabor Altdorfer, Nam Phong Nguyen, Gordon Jendrasiak

Department of Medical Oncology Faculty Papers

Magnetic resonance spectroscopy (MRS) is a non-invasive technique to detect metabolites within the normal and tumoral tissues. The ability of MRS to diagnose areas of high metabolic activity linked to tumor cell proliferation is particularly useful for radiotherapy treatment planning because of better gross tumor volume (GTV) delineation. The GTV may be targeted with higher radiation dose, potentially improving local control without excessive irradiation to the normal adjacent tissues. Prostate cancer and glioblastoma multiforme (GBM) are two tumor models that are associated with a heterogeneous tumor distribution. Preliminary studies suggest that the integration of MRS into radiotherapy planning for these …

Manganese-Containing Prussian Blue Nanoparticles For Imaging Of Pediatric Brain Tumors, Matthieu F. Dumont, Sridevi Yadavilli, Raymond Sze, Javad Nazarian, Rohan Fernandes

Radiology Faculty Publications

Pediatric brain tumors (PBTs) are a leading cause of death in children. For an improved prognosis in patients with PBTs, there is a critical need to develop molecularly-specific imaging agents to monitor disease progression and response to treatment. In this paper, we describe manganese-containing Prussian blue nanoparticles as agents for molecular magnetic resonance imaging (MRI) and fluorescence-based imaging of PBTs. Our core-shell nanoparticles consist of a core lattice structure that incorporates and retains paramagnetic Mn²⁺ ions, and generates MRI contrast (both negative and positive). The biofunctionalized shell is comprised of fluorescent avidin, which serves the dual purpose of enabling …

Use Of Positron Emission To Mography For Proton Therapy Verification, Jongmin Cho

Dissertations and Theses (Open Access)

Positron emission tomography (PET), a tool commonly used for cancer staging and response monitoring, has recently been used for proton therapy verification. By imaging tissue activation following proton treatment, attempts have been made to verify proton dose and range. In this dissertation, two novel approaches were developed and tested for the purpose of help improve the proton dose and range estimation as well as verification.

Although there are still some challenges, attempts for proton dose verification using PET has been made by comparing Monte Carlo dose and PET simulations with treatment planned dose and measured PET. In this approach, …

Performance Evaluation Of Material Decomposition Using Rapid Kvp-Switching Dual-Energy Ct For Assessing Bone Mineral Density, John M. Wait

Dissertations and Theses (Open Access)

Osteoporosis is diagnosed by assessing the bone mineral density (BMD) of the trabecular bone, and has previously been characterized with dual-energy x-ray absorptiometry (DXA) or single-energy computed tomography (SECT). Dual-energy computed tomography (DECT) is able to create two three-dimensional sets of images representing the densities of two materials in a given basis pair. DECT is theoretically capable of providing a true density measurement of trabecular bone material with the proper material basis pair.

Using the rapid kVp-switching GE HD750 scanner, the concentrations of various solutes were assessed in two-material syringe-phantoms in different experimental conditions with DECT material density images, SECT …

Thermal Dosimetry Characteristics Of Deep Regional Heating Of Non-Muscle Invasive Bladder Cancer., Titania Juang, Paul R. Stauffer, Oana A Craciunescu, Paolo F Maccarini, Yu Yuan, Shiva K Das, Mark W Dewhirst, Brant A Inman, Zeljko Vujaskovic

Department of Radiation Oncology Faculty Papers

PURPOSE: The aim of this paper is to report thermal dosimetry characteristics of external deep regional pelvic hyperthermia combined with intravesical mitomycin C (MMC) for treating bladder cancer following transurethral resection of bladder tumour, and to use thermal data to evaluate reliability of delivering the prescribed hyperthermia dose to bladder tissue.

MATERIALS AND METHODS: A total of 14 patients were treated with MMC and deep regional hyperthermia (BSD-2000, Sigma Ellipse or Sigma 60). The hyperthermia objective was 42° ± 2 °C to bladder tissue for ≥40 min per treatment. Temperatures were monitored with thermistor probes and recorded values were used …

A Pilot Clinical Trial Of Intravesical Mitomycin-C And External Deep Pelvic Hyperthermia For Non-Muscle-Invasive Bladder Cancer., Brant A Inman, Paul R. Stauffer, Oana A Craciunescu, Paolo F Maccarini, Mark W Dewhirst, Zeljko Vujaskovic

Department of Radiation Oncology Faculty Papers

PURPOSE: This paper aims to evaluate the safety and heating efficiency of external deep pelvic hyperthermia combined with intravesical mitomycin C (MMC) as a novel therapy for non-muscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS: We enrolled subjects with bacillus Calmette-Guérin (BCG) refractory NMIBC to an early phase clinical trial of external deep pelvic hyperthermia (using a BSD-2000 device) combined with MMC. Bladders were heated to 42 °C for 1 h during intravesical MMC treatment. Treatments were given weekly for 6 weeks, then monthly for 4 months. Heating parameters, treatment toxicity, and clinical outcomes were systematically measured.

RESULTS: Fifteen patients were …

Neuroimaging Of Unusual Glioblastoma Using Diffusion Tensor Imaging, Akshita Mehta, Lucien M. Levy, M. Isabel Almira-Suarez, Raymond Tu

GW Research Days 2014

Background: Gliosarcoma refers to an uncommon astrocytic tumor of the central nervous system. These tumors include both glial and mesenchymal components by definition, and are extremely malignant. Gliosarcomas are particular to tumors with distinct gliomatous and sarcomatous constituents, and are distinguished from gliobastomas which have undergone mesenchymal metaplasia. Gliosarcomas encompass 2-8% of all glioblastoma cases and tend to occupy the supratentorial regions of the brain, especially the temporal lobe. Rare infratentorial lesions including the cerebellar hemisphere, intraventricular, and multi-focal tumors have also been reported. Accurate neuroimaging diagnosis is critical and diffusion tensor imaging (DTI) and spectroscopy can be useful to …

Labrad : Vol 40, Issue 1 - April 2014, Aga Khan University Hospital, Karachi

LABRAD - Departments of Pathology & Laboratory Medicine and Radiology Archives

• Provocative Testing for Growth Hormone Disorders
• Serum Procalcitonin for Early Sepsis Diagnosis
• Monoclonal Gammopathy of Undetermined Significance (MGUS)
• Understanding Six Sigma Methodology
• Blood Collection for Culture
• Molecular Analysis of Alpha Thalassaemia by Multiple Ligation Probe Assay
• Prognostification of Acute Myeloid Leukemia with FLT 3 Mutation
• Interferon Gamma Release Assay (IGRA) for Detection of Mycobacterium Tuberculosis Infection in the Host
• Meeting Report: The 37th Annual Conference of the Pakistan Association of Pathologists

Correlations Of Skin Fold Thickness And Validation Of Prediction Equations Using Dexa As The Gold Standard For Estimation Of Body Fat Composition In Pakistani Children., Zainab Hussain, Tazeen H. Jafar, Maseeh Uz Zaman, Riffat Parveen Hussain

Department of Radiology

OBJECTIVE:

To determine the correlation between dual energy X-ray absorptiometry (DEXA) and skin fold thickness (SKF) equations for estimation of body fat (BF) composition in secondary school children and validation of prediction equations by Slaughter, Goran and Dezenberg.

DESIGN:

Cross sectional analytical study.

SETTING:

Joint Commission for International Accredited (JCIA) tertiary care hospital of Karachi, Pakistan from January 2010 to May 2010.

PARTICIPANTS:

The study was approved by the Hospital's ethical review committee. Written and verbal consents were obtained from principals of two schools and parents of 99 children (mean age of 14±1.89 years; min-max 9-19 years; 54 men and …

Tumor Radiation Therapy Creates Therapeutic Vaccine Responses To The Colorectal Cancer Antigen Gucy2c., Matthew Witek, Erik S Blomain, Michael Sullivan Magee, Bo Xiang, Scott A Waldman, Adam E. Snook

Department of Pharmacology and Experimental Therapeutics Faculty Papers

PURPOSE: Radiation therapy (RT) is thought to produce clinical responses in cancer patients, not only through direct toxicity to cancer cells and supporting tumor stroma cells, but also through activation of immunologic effectors. More recently, RT has potentiated the local and systemic effects of cancer immunotherapy (IT). However, combination regimens that maximize immunologic and clinical efficacy remain undefined.

METHODS AND MATERIALS: We evaluated the impact of local RT on adenoviral-mediated vaccination against the colorectal cancer antigen GUCY2C (Ad5-GUCY2C) in a murine subcutaneous tumor model using mouse CT26 colon cancer cells (CT26-GUCY2C). Immune responses were assessed by ELISpot, and clinical responses …

3d Visualization Architecture For Building Applications Leveraging An Existing Validated Toolkit, David A. Polyak

Master's Theses (2009 -)

The diagnostic radiology space and healthcare in general is a slow adopter of new software technologies and patterns. Despite the widespread embrace of mobile technology in recent years, altering the manner in which societies in developed countries live and communicate, diagnostic radiology has not unanimously adopted mobile technology for remote diagnostic review. Desktop applications in the diagnostic radiology space commonly leverage a validated toolkit. Such toolkits not only simplify desktop application development but minimize the scope of application validation. For these reasons, such a toolkit is an important piece of a company’s software portfolio. This thesis investigated an approach for …

Introducing And Evaluating 3d Digital Breast Tomosynthesis, Marie Hrinkonich, Susan Steigerwalt

Department of Radiology & Diagnostic Medical Imaging

No abstract provided.

5-Fu Induced Acute Toxic Leukoencephalopathy: Early Recognition And Reversibility On Dwi-Mri, Shayan Sirat Maheen Anwar,, Fatima Mubarak, Zafar Sajjad, Muhammad Azeemuddin

Department of Radiology

Acute toxic leukoencephalopathy (ATL) is a rare adverse effect of 5-Fluorouracil (5-FU) chemotherapeutic agent. It is imperative for the radiologist to confidently identify the white matter changes caused by this agent in case of toxicity. This will help in early detection and appropriate management of patient, as the condition is reversible both clinically and on imaging. We report a case of a 29 years old gentleman, known case of carcinoma of esophagus who suffered from acute toxic leukoencephalopathy secondary to leukotoxic therapeutic agent 5-FU, and illustrate the reversible imaging findings of this condition on withdrawal of the inciting agent.

A Randomized Trial Of Bevacizumab For Newly Diagnosed Glioblastoma., Mark R Gilbert, James J Dignam, Terri S Armstrong, Jeffrey S Wefel, Deborah T Blumenthal, Michael A Vogelbaum, Howard Colman, Arnab Chakravarti, Stephanie Pugh, Minhee Won, Robert Jeraj, Paul D Brown, Kurt A Jaeckle, David Schiff, Volker W Stieber, David G Brachman, Maria Werner-Wasik, Ivo W Tremont-Lukats, Erik P Sulman, Kenneth D Aldape, Walter J Curran, Minesh P Mehta

Department of Radiation Oncology Faculty Papers

BACKGROUND: Concurrent treatment with temozolomide and radiotherapy followed by maintenance temozolomide is the standard of care for patients with newly diagnosed glioblastoma. Bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor A, is currently approved for recurrent glioblastoma. Whether the addition of bevacizumab would improve survival among patients with newly diagnosed glioblastoma is not known.

METHODS: In this randomized, double-blind, placebo-controlled trial, we treated adults who had centrally confirmed glioblastoma with radiotherapy (60 Gy) and daily temozolomide. Treatment with bevacizumab or placebo began during week 4 of radiotherapy and was continued for up to 12 cycles of maintenance chemotherapy. …