Medical Specialties Commons^™

Radionuclide Imaging: Past, Present And Future Outlook In The Diagnosis Of Infected Prosthetic Joints, L. Brammen, C. Palestro, H. Sinzinger

Journal Articles

Objective: A serious complication of joint replacement surgery is infection, which results in prolonged invalidity as well as removal and subsequent re-implantation after lengthy antibiotic therapy. In terms of diagnostic imaging, nuclear medicine has presented several tracers and imaging modalities over the years to be used in prosthetic joint infection. The PubMed/MEDLINE literature database was systematically examined for publications on infection, arthroplasty, joint replacement, prosthetic joint, gallium, labeled leukocytes, sulfur colloid, antimicrobial peptides, Fluorine-18-fluorodeoxyglucose (F-18-FDG), positron emission tomography/computed tomography (PET-CT), and single-photon emission (SPET-CT). This was determined to be a comprehensive review, not a meta-analysis of prosthetic joint infection and …

Detection Of Symptomatic Carotid Plaque Using Source Data From Mr And Ct Angiography: A Correlative Study, A. Gupta, H. Baradaran, E. E. Mtui, H. Kamel, A. Pandya, A. Giambrone, C. Iadecola, P. C. Sanelli

Journal Articles

BACKGROUND: Carotid plaque MRI has been a useful method to characterize vulnerable atherosclerotic plaque elements. Recent investigations have suggested that source images from CT angiography (CTA) and MR angiography (MRA) can identify the simple high-risk features of symptom-producing carotid artery plaque. We studied the correlation and relative diagnostic accuracies of CTA and MRA source images in detecting symptomatic carotid artery plaque. METHODS: Subjects were eligible if they had carotid stenosis between 50 and 99% and had MRA and CTA exams performed within 10 days of one another. We measured the soft (non-calcified) plaque and hard (calcified) plaque thickness on CTA …

Evaluating Blood-Brain Barrier Permeability In Delayed Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage, J. Ivanidze, K. Kesavabhotla, O. N. Kallas, D. Mir, H. Baradaran, A. Gupta, A. Z. Segal, J. Claassen, P. C. Sanelli

Journal Articles

BACKGROUND AND PURPOSE: Patients with SAH are at increased risk of delayed infarction. Early detection and treatment of delayed infarction remain challenging. We assessed blood-brain barrier permeability, measured as permeability surface area product, by using CTP in patients with SAH with delayed infarction. MATERIALS AND METHODS: We performed a retrospective study of patients with SAH with delayed infarction on follow-up NCCT. CTP was performed before the development of delayed infarction. CTP data were postprocessed into permeability surface area product, CBF, and MTT maps. Coregistration was performed to align the infarcted region on the follow-up NCCT with the corresponding location on …

Emphysematous Pyelonephritis, N. Kim, S. Machnicki

Journal Articles

No abstract provided.

A Mobile Image Enhancement Technology For Visually Impaired, Fahao Qiao

Dissertations, Master's Theses and Master's Reports - Open

In this thesis, an image enhancement application is developed for low-vision patients when they use iPhones to see images/watch videos. The thesis has two contributions. The first contribution is the new image enhancement algorithm which combines human vision features. The new image enhancement algorithm is modified from a wavelet transform based image enhancement algorithm developed by Dr. Jinshan Tang. Different from the original algorithm, the new image enhancement algorithm combines human visual feature into the algorithm and thus can make the new algorithm more effective. Experimental simulation results show that the proposed algorithm has better visual results than the algorithm …

Functional Properties Of Resting State Networks In Healthy Full-Term Newborns., Josepheen De Asis-Cruz, Marine Bouyssi-Kobar, Iordanis Evangelou, Gilbert Vezina, Catherine Limperopoulos

Radiology Faculty Publications

Objective, early, and non-invasive assessment of brain function in high-risk newborns is critical to initiate timely interventions and to minimize long-term neurodevelopmental disabilities. A prerequisite to identifying deviations from normal, however, is the availability of baseline measures of brain function derived from healthy, full-term newborns. Recent advances in functional MRI combined with graph theoretic techniques may provide important, currently unavailable, quantitative markers of normal neurodevelopment. In the current study, we describe important properties of resting state networks in 60 healthy, full-term, unsedated newborns. The neonate brain exhibited an efficient and economical small world topology: densely connected nearby regions, sparse, but …

Computer Aided Diagnosis Of Oral Cancer: Using Time-Step Ct Images, Jonathan T. Scott

Masters Theses

"In medical imaging it is a very common practice to use a technique known as Time-Step imaging in patients who might develop cancer. Time-Step imaging it a very powerful technique, however it can lead to unmanageable amounts of image data. Previously the only way to search all of this data was to manually look through all of the files. This had to be done by trained professionals who knew what to look for within the images and make a judgment about the patient based on the images. This paper discusses the development of an algorithm to have a computer search …

Metastatic Pancreatic Carcinoma And Experience With Folfirinox - A Cross Sectional Analysis From A Developing Country, Muhammad Nauman Zahir, Adnan Abdul Jabbar

Department of Radiation Oncology

Background: Pancreatic cancer is the fourth leading cause of cancer related death with median survival ranging from 3 to 6 months for metastatic disease. Palliative chemotherapy has been the backbone of treatment in advanced stage and has evolved over time. Data pertaining to the disease are scarce from our part of the world where treatment poses a significant challenge due to lack of resources.MATERIALS AND Methods: A retrospective chart review was performed for all patients presenting with stage IV pancreatic carcinoma at a tertiary care hospital in Karachi, Pakistan between January 2008 and December 2012. Data were collected using a …

Fortifying The External Peer Review: An Editorial Perspective, Saba Sohail

Department of Radiology

No abstract provided.

Diagnostic Performance Of Breast Mri In The Evaluation Of Contralateral Breast In Patients With Diagnosed Breast Cancer, Shaista Afzal Saeed, Imrana Masroor, Madiha Beg, Romana Idress

Department of Radiology

AIMS: The purpose of our study was to evaluate the diagnostic performance of breast magnetic resonance imaging (MRI) in the evaluation of contralateral breast in patients with diagnosed breast cancer. A secondary objective was to determine accuracy of breast MRI in diagnosing multi-focal and multicentric lesions in the ipsilateral breast.MATERIALS AND Methods: Using a non-probability convenience sampling technique, patients with histopathologically diagnosed breast cancer with MRI of breast performed to exclude additional lesions were included. MRI findings were correlated with histopathology. In addition, follow-up imaging with mammography and ultrasound was also assessed for establishing stability of negative findings and for …

Temporal Trends In Results Of 9170 Myocardial Perfusion Imaging Studies (2004 To 2013)., Nosheen Fatima

Department of Surgery Docs

Abstract

BACKGROUND:

To assess the frequency of normal and abnormal myocardial perfusion imaging (MPI) in a consecutive cohort of patients from Pakistan over a period of 8.5 years.

MATERIAL AND METHODS:

We assessed 9170 patients who had undergone stress-rest MPI between January 2004 and June 2013. Patients were assessed for change in demographics, risk factors, and frequency of abnormal and normal MPI.

RESULTS:

Overall mean age and male predominance of studied cohort was ≈ 55 years and ≈ 55:45 (M:F), respectively, with no appreciable decline or rise. Marked decline in exercise as mode of stress (from 71% to 35%, p …

Grid-Based Fourier Transform Phase Contrast Imaging, Sajjad Tahir

Legacy Theses & Dissertations (2009 - 2024)

Low contrast in x-ray attenuation imaging between different materials of low electron density is a limitation of traditional x-ray radiography. Phase contrast imaging offers the potential to improve the contrast between such materials, but due to the requirements on the spatial coherence of the x-ray beam, practical implementation of such systems with tabletop (i.e. non-synchrotron) sources has been limited. One recently developed phase imaging technique employs multiple fine-pitched gratings. However, the strict manufacturing tolerances and precise alignment requirements have limited the widespread adoption of grating-based techniques. In this work, we have investigated a technique recently demonstrated by Bennett et al.1 …

Phase Imaging Using Focusing Polycapillary Optics, Sajid Bashir

Legacy Theses & Dissertations (2009 - 2024)

The interaction of X rays in diagnostic energy range with soft tissues can be described by Compton scattering and by the complex refractive index, which together characterize the attenuation properties of the tissue and the phase imparted to X rays passing through it. Many soft tissues exhibit extremely similar attenuation, so that their discrimination using conventional radiography, which generates contrast in an image through differential attenuation, is challenging. However, these tissues will impart phase differences significantly greater than attenuation differences to the X rays passing through them, so that phase-contrast imaging techniques can enable their discrimination.

Uterine Fibroid Embolization For Symptomatic Fibroids: Study At A Teaching Hospital In Kenya, John Mutai, Sudhir Vinayak, William Stones, Nigel Hacking, Charles Mariara

Imaging & Diagnostic Radiology, East Africa

Objective: Characterization of magnetic (MRI) features in women undergoing uterine fibroid embolization (UFE) and identification of clinical correlates in an African population.

Materials and Methods: Patients with symptomatic fibroids who are selected to undergo UFE at the hospital formed the study population. The baseline MRI features, baseline symptom score, short-term imaging outcome, and mid-term symptom scores were analyzed for interval changes. Assessment of potential associations between short-term imaging features and mid-term symptom scores was also done.

Results: UFE resulted in statistically significant reduction (P < 0.001) of dominant fibroid, uterine volumes, and reduction of symptom severity scores, which were 43.7%, 40.1%, and 37.8%, respectively. Also, 59% of respondents had more than 10 fibroids. The predominant location of the dominant fibroid was intramural. No statistically significant association was found between clinical and radiological outcome.

Conclusion: The response of uterine fibroids to embolization in the African population is not different …

Management Of Radioactive Spills In Nuclear Medicine; Teaching And Assessing With Objectively Structured Assessment Of Technical Skills, Riffat Parveen Hussain

Department of Radiology

Routine work in nuclear medicine requires the careful elution of radioactivity and its subsequent, storage and handling. Though all effort is maintained to prevent any "spill" of this radioactivity, accidents are bound to happen. The response to this spill is a methodically worked out a plan that is written and adopted as a "standard operating procedure." This protocol is taught to all involved in the area of working as a mock drill/apprenticeship model. No formal evaluation of learning is in place except for the mock drills. The objectively structured assessment of technical skills (OSATS) is a variation on the Objective …

Comparison Of Microcoils And Polyvinyl Alcohol Particles In Selective Microcatheter Angioembolization Of Non Variceal Acute Gastrointestinal Hemorrhage, Tanveer-Ul-Haq, Muhammad Idris, Basit Salam, Waseem Akhtar, Yasir Jamil

Department of Radiology

Objectives: To compare the efficacy of polyvinyl alcohol (PVA) particles with microcoils in angiembolisation of non variceal acute gastrointestinal haemorrhage.Methods: This is a retrospective cross-sectional study of patients who underwent transcatheter angioembolization from January, 1995 to December, 2013 at Aga Khan University Hospital, Karachi. Patients were divided into two groups on basis of use of either microcoils or PVA particles and compared in terms of technical success, clinical success, re-bleeding and ischemic complication rates. Chi (chi(2)) square and Fisher's exact tests were applied and a P-value of less than 0.05 was considered statistically significant.Results: Fifty seven patients underwent angioembolization. Microcoil …

Evaluation Of Common Risk Factors For Breast Carcinoma In Females: A Hospital Based Study In Karachi, Pakistan, Saira Naz, Imrana Masroor, Waseem Mirza, Sehrish Abrar, Shaista Afzal Saeed, Zafar Sajjad

Department of Radiology

Background: Breast malignancies are one of the leading causes of deaths in females worldwide. There are a number of risk factors associated with breast cancer but in Karachi Pakistan there are insufficient data available.
Materials and methods: A case control study was conducted on females in age group between 30-80 years. This study was accomplished by retrospective data collection in Aga Khan University Hospital Karachi, Pakistan. A total of 108 females with primary malignancy of breast were included along with 108 matched controls. Relationship of various factors with disease was studied using logistic regression to calculate odds ratios with 95 …

Computer Aided Detection Of Oral Lesions On Ct Images, Shaikat Mahmood Galib

Masters Theses

"Oral lesions are important findings on computed tomography images. They are difficult to detect on CT images because of low contrast, arbitrary orientation of objects, complicated topology and lack of clear lines indicating lesions. In this thesis, a fully automatic method to detect oral lesions from dental CT images is proposed to identify (1) Closed boundary lesions and (2) Bone deformation lesions. Two algorithms were developed to recognize these two types of lesions, which cover most of the lesion types that can be found on CT images. The results were validated using a dataset of 52 patients. Using non training …

Outcome And Cost Effectiveness Of Autobiographically Guided Surgical Clip Placement For Tumor Localization In Patients Undergoing Neo-Adjuvant Chemotherapy For Breast Cancer., Imrana Masroor, Sana Zeeshan, Shaista Afzal Saeed, Saira Naz, Madeeha Ali, Khabir Ahmad, Shaista Khan

Department of Surgery Docs

Abstract

BACKGROUND:

To determine the outcome and cost saving by placing ultrasound guided surgical clips for tumor localization in patientsundergoing neo-adjuvant chemotherapy for breast cancer.

MATERIALS AND METHODS:

This retrospective cross sectional analytical study was conducted at the Department of Diagnostic Radiology, Aga Khan University Hospital, Karachi, Pakistan from January to December 2014. A sample of 25 women fulfilling our selection criteria was taken. All patients came to our department for ultrasound guided core biopsy of suspicious breast lesions and clip placement in the index lesion prior to neo-adjuvant chemotherapy. All the selected patients had biopsy proven breast cancer.

RESULTS: …

Promoting Comfort During Ct-Coronary Angiogram, Margo Archer, Dawn Arevalo, Kelly Vazquez

All Publications

No abstract provided.

Bright Facet Sign And Its Association With Demographic And Clinical Variables, Gary Andrew Longmuir

Walden Dissertations and Doctoral Studies

Low back pain has a significant impact on global public health and economics. The bright facet sign (BFS), a common finding on magnetic resonance imaging (MRI) of the lumbar spine, is associated with low back pain. While degenerative joint disease (DJD) affects low back pain, its presence appears independent of the BFS at the disc and facet joints at the same spinal level. Increased BMI, considered a risk factor for DJD, has an inverse association with the BFS. The independent relationship of DJD and the BFS is poorly understood and may represent a previously unreported pain pathway. In this nested …

Case 213: Primary Spenic Angiosarcoma, John J. Krol, Vera V. Krol, Adrian Dawkins, Halemane S. Ganesh

Radiology Faculty Publications

A 75-year-old woman with a medical history of gastroesophageal reflux disease and type II diabetes presented to the hospital with a 3-month history of gradually worsening headaches, vague upper abdominal pain, and lower back pain. The patient denied fevers, night sweats, contact with sick individuals, occupational exposure to infection, bleeding, immunodeficiency, intravenous drug use, alcohol or tobacco abuse, history of malignancy, family history of genetic disorders, and international travel. Physical examination revealed a skin-colored mass protruding from the right side of her forehead, but there were no other notable abnormalities. Her diabetes was managed with diet, and the only prescription …

Plasmablastic Lymphoma Of The Oral Cavity With Breast Recurrence: A Case Report, Zarka Samoon, Romana Idrees, Nehal Masood, Tayyaba Zehra Ansari

Department of Radiation Oncology

Background: Plasmablastic lymphoma is an aggressive variant of diffuse large B cell lymphoma, mostly found in the oral cavity and associated with human immunodeficiency virus. There are no clear guidelines for its treatment. Therapies more intensive than cyclophosphamide, doxorubicin, vincristine, and prednisone are not associated with a prolonged survival. Lymphomas of the breast are rare, in one series representing 0.14% of all female breast malignancies, with diffuse large B cell lymphoma comprising up to 55% of all cases. Only one case of plasmablastic lymphoma involving the breast has been reported in the literature.CASE PRESENTATION: A 30 year old Pakistani woman, …

The Multimodal Brain Tumor Image Segmentation Benchmark (Brats), Bjoern H. Menze, Andras Jakab, Stefan Bauer, Jayashree Kalpathy-Cramer, Khan M. Iftekharuddin, Syed M.S. Reza

Electrical & Computer Engineering Faculty Publications

In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low-and high-grade glioma patients-manually annotated by up to four raters-and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74%-85%), illustrating the difficulty of this task. We found that different algorithms worked best for different sub-regions …

Evaluation Of Common Risk Factors For Breast Carcinoma In Females: A Hospital Based Study In Karachi, Pakistan, Saira Naz Sufian, Imrana Masroor, Waseem Mirza, Sehrish Butt, Shaista Afzal, Zafar Sajjad

Department of Radiology

Background: Breast malignancies are one of the leading causes of deaths in females worldwide. There are a number of risk factors associated with breast cancer but in Karachi Pakistan there are insufficient data available.
Materials and methods: A case control study was conducted on females in age group between 30-80 years. This study was accomplished by retrospective data collection in Aga Khan University Hospital Karachi, Pakistan. A total of 108 females with primary malignancy of breast were included along with 108 matched controls. Relationship of various factors with disease was studied using logistic regression to calculate odds ratios with 95 …

Fibrodysplasia Ossificans Progressiva Misdiagnosed As Cervical Exostosis, Muhammad Awais, Abdul Rehman, Noor Ul-Ain Baloch

Department of Radiology

No abstract provided.

Pseudo-Thyroid Lobe: A Diagnostic Conundrum Caused By Ossified Anterior Longitudinal Ligament On Bone Scan, Maseeh Uz Zaman, Nosheen Fatima, Zafar Sajjad, Unaiza Zaman, Areeba Zaman, Rabia Tahseen

Department of Radiology

Radionuclide bone imaging is one of the most commonly performed nuclear medicine procedure around the world and characterized by its high sensitivity and relatively low specificity. False positive findings on a bone scan are very common; however, dense uptake over unilateral ossified anterior longitudinal ligament appearing as single thyroid lobe on a bone scan has not been described in the literature.

Toxicity And Cosmesis Outcomes For Single Fraction Intra-Operative Electron Radiotherapy (Ioert) For Breast Cancer, Monica Hanna, Robert Ash, Wesley Babaran, Michele M. Carpenter, Afshin Forouzannia, Jay K. Harness, Brian Kaltenecker, Snehith Maddula, Venita Williams, Lawrence Wagman

Student Scholar Symposium Abstracts and Posters

Background: Adjuvant radiation therapy is proven to reduce local recurrence in patients with early stage breast cancer. To reduce toxicity, improve geographic accuracy, and reduce treatment time, IOERT can be utilized as an alternative to external beam radiation therapy. The study’s objective was to determine the short term toxicity and cosmesis profile of single fraction IOERT given as definitive treatment in a community setting. Materials and Methods: From Mar 2012 to Jul 2014, 84 patients (3 bilateral), ages 45-91 y.o. with stage 0-II were treated with IOERT (Mobetron, IntraOp Medical, Sunnyvale, CA). A single 21 Gy fraction was administered to …

Toward An Improved Understanding Of The Ionizing Radiation Induced Dna Damage/Response Networks In Human Malignancies., Daphne A Haas-Kogan, David R Raleigh, Adam Paul Dicker

Department of Radiation Oncology Faculty Papers

No abstract provided.

Comparison Between Greulich-Pyle And Girdany-Golden Methods For Estimating Skeletal Age Of Children In Pakistan, Muhammad Awais, Naila Nadeem, Yousuf Husen, Abdul Rehman, Madiha Beg, Yasir Jamil Khattak

Department of Radiology

Objective: To compare Greulich-Pyle (GP) and Girdany-Golden (GG) methods for estimation of Skeletal Age (SA) in children referred to a tertiary care hospital in Karachi, Pakistan.STUDY Design: Cross-sectional study.PLACE AND DURATION OF STUDY: Department of Radiology, The Aga Khan University Hospital, Karachi, Pakistan, from July 2010 to June 2012.METHODOLOGY: Children up to the age of 18 years, who had undergone X-ray for the evaluation of trauma were included. Each X-ray was interpreted using both methods by two consultant paediatric radiologists having at least 10 years experience, who were blinded to the actual Chronologic Age (CA) of children.Results: A total of …