Radiology Commons^™

Mdct Of Small Bowel Obstruction: How Reliable Are Oblique Reformatted Images In Localizing Point Of Transition?, Wasim Memon, Yasir Jamil Khattak, Tariq Alam, Luca Maria Sconfienza, Muhammad Awais, Shayan Sirat Maheen Anwar

Department of Radiology

The goal of this study is to prospectively assess the additional value of oblique reformatted images for localizing POT, having surgery as a reference standard. Materials and Methods. 102 consecutive patients with suspected small bowel obstruction (SBO) underwent 64-slice multidetector row CT (MDCT) using surgical findings as reference standard. Two independent GI radiologists reviewed the CT scans to localize the exact POT by evaluating axial images (data set A) followed by axial, coronal, and oblique MPR images. CT findings were compared to surgical findings in terms of diagnostic performance. McNemar's test was used to detect any statistical difference in POT …

Assessment Of Apparent Diffusion Coefficient Values As Predictor Of Aggressiveness In Peripheral Zone Prostate Cancer: Comparison With Gleason Score, Shayan Sirat Maheen Anwar, Zahid Anwar Khan, Rana Shoaib Hamid, Fahd Haroon, Raza Sayani, Madiha Beg, Yasir Jamil Khattak

Department of Radiology

Purpose. To determine association between apparent diffusion coefficient value on diffusion-weighted imaging and Gleason score in patients with prostate cancer. Methods. This retrospective case series was conducted at Radiology Department of Aga Khan University between June 2009 and June 2011. 28 patients with biopsy-proven prostate cancer were included who underwent ultrasound guided sextant prostate biopsy and MRI. MRI images were analyzed on diagnostic console and regions of interest were drawn. Data were entered and analyzed on SPSS 20.0. ADC values were compared with Gleason score using one-way ANOVA test. Results. In 28 patients, 168 quadrants were biopsied and 106 quadrants …

Knowledge, Attitudes And Practices Of Parents Regarding Antibiotic Use In Children, Saad Siddiqui, Mubeen Sultan Cheema, Romana Ayub, Noreen Shah, Ameer Hamza, Sheraz Hussain, Muhammad Hamza Khan, Syed Musa Raza

Department of Radiology

Background: Emerging resistance to antimicrobial chemotherapy is becoming a challenge for medicine in recent times. Un-prescribed use of antibiotics is a major contributor to development of this problem. In Pakistan access to antibiotics remains unchecked and hence results in it are over use. The aim of this study was to assess knowledge of parents regarding use of antibiotics, its associated problems, their source of information and their expectations from Paediatricians for prescription of anti-biotics.Methods: This is a questionnaire based cross sectional study conducted in Hayatabad town, District Peshawar. Parents who were consenting, had children aged between 0-16 years, and were …

Cervical Cancer Histology Image Feature Extraction And Classification, Peng Guo

Masters Theses

"Cervical cancer, the second most common cancer affecting women worldwide and the most common in developing countries can be cured if detected early and treated. Expert pathologists routinely visually examine histology slides for cervix tissue abnormality assessment. In previous research, an automated, localized, fusion-based approach was investigated for classifying squamous epithelium into Normal, CIN1, CIN2, and CIN3 grades of cervical intraepithelial neoplasia (CIN) based on image analysis of 62 digitized histology images obtained through the National Library of Medicine. In this research, CIN grade assessments from two pathologists are analyzed and are used to facilitate atypical cell concentration feature development …

Utility Of Microwave Radiometry For Diagnostic And Therapeutic Applications Of Non-Invasive Temperature Monitoring, Paul R. Stauffer, Dario B. Rodrigues, Paolo F. Maccarini

Department of Radiation Oncology Faculty Papers

This paper describes the use of microwave radiometry for several diagnostic and therapeutic applications that can benefit from accurate non-invasive measurement of volume average temperature of tissue regions extending 4cm or more into the body. Design features are summarized for an appropriate high sensitivity long term stable system with 2.5 and 7 cm diameter receive antennas and integral 1.35 GHz total power radiometer electronics. Radiometer performance is characterized with electromagnetic and thermal simulations and experimental measurements in realistic models of two typical clinical applications. Results demonstrate sufficient sensitivity to track clinically significant changes in temperature of deep tissue targets for …

The Utility Of A Tablet Computer Device In Comparison To A Standard High Resolution Monitor For Reporting Ct Kub Images, Kenneth Kiriinya Ibeere

Master of Medicine in Imaging and Diagnostic Radiology

Background: The latest technological developments in the field of digital medical imaging have facilitated the transfer of the power and utility of the personal computer to mobile computing devices. One of these that have been used in diagnostic imaging is a tablet computer. Mobile tele-radiology using a tablet computer device is an apt extension of imaging services, for after-office-hours consultation. It is crucial to determine the diagnostic accuracy of these portable computer devices in order to determine safety for use in diagnostic image interpretation without compromising patient care. Objective: To find out the diagnostic accuracy of urolithiasis (urinary tract calculi) …

Prediction Of Breast Tumor Size By Ultrasound: A Comparison With Pathology, David Toyis Wanyonyi

Master of Medicine in Imaging and Diagnostic Radiology

Background: Tumor size is one of the most important prognostic factors in breast cancer and its accurate assessment is critical in planning appropriate treatment. Although histology is often regarded as the definitive way of establishing tumor size, radiological techniques, particularly ultrasonography, are usually relied upon to give an estimate of the tumor size for prognostication and treatment planning. Correlations between mammography, ultrasonography, magnetic resonance imaging (MRI) and pathology size have been performed in different populations with varying results however no prospective study has been done to establish the agreement between sonographic tumor size and histopathological tumor size in our population. …

Prevalence Of Significant Liver Fibrosis In Patients With Hiv Monoinfection Compared To Those With Hiv-Hepatitis B Coinfection As Assessed By Shear Wave Elastography, Samuel Nguku

Master of Medicine in Imaging and Diagnostic Radiology

Background: Liver disease is an emerging management problem in human immunodeficiency virus (HIV) infected patients. The incidence of chronic Hepatitis B infection, which accelerates the progression of chronic liver disease and development of liver fibrosis, is ten times higher in patients with HIV than the general population. Staging of liver fibrosis provides essential information in management of these patients. Objective: To determine the prevalence of significant liver fibrosis in patients with HIV mono-infection versus those with HIV-HBV co-infection as assessed with shear wave elastography (SWE). Methods: This was a cross-sectional study whereby HIV infected patients attending the HIV clinic at …

Use Of An Electrical Impedance Tomography Method To Detect And Track Fractures In A Gelatin Medium, Evan G. Lucas

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

Electrical impedance tomography is applied to the problem of detecting, locating, and tracking fractures in ballistics gelatin. The hardware developed is intended to be physically robust and based on off-the-shelf hardware. Fractures were created in two separate ways: by shooting a .22 caliber bullet into the gelatin and by injecting saline solution into the gelatin. The .22 caliber bullet created an air gap, which was seen as an increase in resistivity. The saline solution created a fluid filled gap, which was seen as a decrease in resistivity. A double linear array was used to take data for each of the …

Three‐Dimensional Brain Mri For Dbs Patients Within Ultra‐Low Radiofrequency Power Limits, Subhendra N. Sarkar, Efstathios Papavassiliou, David Hackney, David Alsop, Ananth Madhuranthakam, Ludy Shih, Reed Busse, Susan Laruche, Rafeeque Bhadelia

Publications and Research

Background: For patients with deep brain stimulators (DBS), local absorbed radiofrequency (RF) power is unknown and is much higher than what the system estimates. We developed a comprehensive, highquality brain magnetic resonance imaging (MRI) protocol for DBS patients utilizing three-dimensional (3D) magnetic resonance sequences at very low RF power. Methods: Six patients with DBS were imaged (10 sessions) using a transmit/receive head coil at 1.5 Tesla with modified 3D sequences within ultra-low specific absorption rate (SAR) limits (0.1 W/kg) using T2, fast fluid-attenuated inversion recovery (FLAIR) and T1- weighted image contrast. Tissue signal and tissue contrast from the low-SAR images …

An Investigation Of Nurbs-Based Deformable Image Registration, Travis J. Jacobson

Theses and Dissertations

Deformable image registration (DIR) is an essential tool in medical image processing. It provides a means to combine image datasets, allowing for intra-subject, inter-subject, multi-modality, and multi-instance analysis, as well as motion detection and compensation. One of the most popular DIR algorithms models the displacement vector field (DVF) as B-splines, a sum of piecewise polynomials with coefficients that enable local shape control. B-splines have many advantageous properties in the context of DIR, but they often struggle to adequately model steep local gradients and discontinuities. This dissertation addresses that limitation by proposing the replacement of conventional B-splines with a generalized formulation …

A Nonrigid Registration Method For Correcting Brain Deformation Induced By Tumor Resection, Yixun Liu, Chengjun Yao, Fotis Drakopoulos, Jinsong Wu, Liangfu Zhou, Nikos Chrisochoides

Computer Science Faculty Publications

Purpose: This paper presents a nonrigid registration method to align preoperative MRI with intraoperative MRI to compensate for brain deformation during tumor resection. This method extends traditional point-based nonrigid registration in two aspects: (1) allow the input data to be incomplete and (2) simulate the underlying deformation with a heterogeneous biomechanical model.

Methods: The method formulates the registration as a three-variable (point correspondence, deformation field, and resection region) functional minimization problem, in which point correspondence is represented by a fuzzy assign matrix; Deformation field is represented by a piecewise linear function regularized by the strain energy of a heterogeneous biomechanical …

Monitoring Brown Fat Metabolic Activity Using Microwave Radiometry: Antenna Design And Frequency Selection, Dario B. Rodrigues, Paul R. Stauffer, Paolo F. Maccarini

Department of Radiation Oncology Faculty Papers

This paper describes the use of microwave radiometry for monitoring brown fat metabolism (mBAT). The radiometric frequency band and receive antenna were optimized for coupling to 2-6 ml BAT depots in the supraclavicular region. Radiometric signal variations induced by higher metabolic activity resulting from a cold stimulus were calculated with electromagnetic and thermal simulations in a segmented computational model of the human neck including BAT. A 2.5 cm dia. log spiral antenna was selected as optimum using a 500 MHz bandwidth and center frequency 2.75 GHz. Results suggest sufficient sensitivity to track subsurface temperature variations during long term mBAT monitoring …

Novel Microwave Applicators Based On Zero-Order Mode Resonance For Hyperthermia Treatment Of Cancer, David Vrba, Jan Vrba, Paul R. Stauffer

Department of Radiation Oncology Faculty Papers

In this paper, three novel microwave applicator prototypes based on zero-order mode resonators are proposed for use in hyperthermia treatment of cancer. The ability of all three applicators to homogenously irradiate muscle tissue-equivalent phantoms is demonstrated with results of numerical simulations, and relative performance of the applicators is compared.

Accuracy Of Magnetic Resonance Imaging In Pretreatment Lymph Node Assessment For Gynecological Malignancies, Saira Naz Sufian, Imrana Masroor, Waseem Mirza, Zainab Hussain, Saima Hafeez, Zafar Sajjad

Department of Radiology

Objective: To determine the accuracy of magnetic resonance imaging (MRI) in detection of metastasis in pelvic and para-aortic lymph nodes from different gynecological malignancies.MATERIALS AND Methods: This retrospective cross sectional analytic study was conducted at the Department of Diagnostic Radiology, Aga Khan University Hospital Karachi Pakistan from January 2011 to December 2012. A sample of 48 women, age range between 20-79 years, fulfilling inclusion criteria were included. All patients had histopathologically proven gynecological malignancies in the cervix, endometrium or ovary and presented for a pretreatment MRI to our radiology department.Results: MRI was 100% sensitive and had a 100% positive predictive …

Endovascular Embolisation Of Visceral Artery Pseudoaneurysms, Yasir Jamil Khattak, Tariq Alam, Rana Hamid Shoaib, Raza Sayani, Tanveer-Ul Haq, Muhammad Awais

Department of Radiology

Objective. To evaluate the technical success, safety, and outcome of endovascular embolization procedure in management of visceral artery pseudoaneurysms. Materials and Methods. 46 patients were treated for 53 visceral pseudoaneurysms at our institution. Preliminary diagnostic workup in all cases was performed by contrast enhanced abdominal CT scan and/or duplex ultrasound. In all patients, embolization was performed as per the standard departmental protocol. For data collection, medical records and radiology reports of all patients were retrospectively reviewed. Technical success, safety, and outcome of the procedure were analyzed. Results. Out of 46 patients, 13 were females and 33 were males. Mean patient …

Diagnostic Accuracy Of Ultrasonography In Differentiating Benign And Malignant Thyroid Nodules Using Fine Needle Aspiration Cytology As The Reference Standard, Tariq Alam, Yasir Jamil Khattak, Madiha Beg, Abdul Raouf, Muhammad Azeemuddin, Asif Alam Khan

Department of Radiology

Background: In Pakistan thyroid cancer is responsible for 1.2% cases of all malignant tumors. Ultrasonography (US) is helpful in detecting cancerous thyroid nodules on basis of different features like echogenicity, margins, microcalcifications, size, shape and abnormal neck lymph nodes. We therefore aimed to calculate diagnostic accuracy of ultrasound in detection of carcinoma in thyroid nodules taking fine needle aspiration cytology as the reference standard.MATERIALS AND Methods: A cross-sectional analytical study was designed to prospectively collect data from December 2010 till December 2012 from the Department of Radiology in Aga Khan University Hospital, Karachi, Pakistan. A total of 100 patients of …

Pancreatic Lymphangioma, Shaista Afzal, Imrana Masroor, Gulnaz Shafqat

Department of Radiology

Lymphangioma develops as a consequence of lymphatic malformation and blockage of lymphatic flow. Pancreatic lymphangioma is a rare benign tumour which can grow reasonably large prior to manifestation of symptoms. On imaging, it appears as a complex multiseptated cystic mass. However, this appearance is not diagnostic and overlaps with cystic pancreatic neoplasm. We present a case of pancreatic lymphangioma incidentally discovered in an elderly lady who was managed conservatively since surgery could not be performed as the patient was high risk for surgery. Imaging findings along with follow-up of the case and review of literature is presented.

Wandering Meckel's Diverticulum On 99m Technetium-Pertechnetate Scintigraphy: A Diagnostic Dilemma?, Maseeh Uz Zaman, Nosheen Fatima, Unaiza Zaman, Zafar Sajjad

Department of Radiology

Meckel's diverticulum (MD) is the most common gastrointestinal anomaly with heterotopic mucosa in 60% of cases. 99m technetium-pertechnetate scintigraphy is a sensitive tool for detection of MD containing heterotopic gastric mucosa. It is usually located in the right lower quadrant or umbilical region and less frequently in other quadrants. A mobile or wandering MD is a rare clinical presentation and may pose a diagnostic dilemma. However, presence of temporal correlation with gastric activity and compactness of focus during wandering period could make this riddle easy.

Protocol For The Rt Prepare Trial: A Multiple-Baseline Study Of Radiation Therapists Delivering Education And Support To Women With Breast Cancer Who Are Referred For Radiotherapy, Georgia Halkett, Moira O'Connor, Sanchia Aranda, Michael Jefford, Nigel Spry, Therese Shaw, Rachael Moorin, Penelope Schofield

Research outputs 2014 to 2021

Introduction: There is limited evidence to guide the preparation of patients for radiotherapy. This paper describes the protocol for an evaluation of a radiation therapist led education intervention delivered to patients with breast cancer in order to reduce psychological distress. Methods: A multiple-baseline study is being used. Usual care data is being collected prior to the start of the intervention at each of three sites. The intervention is delivered by radiation therapists consulting with patients prior to their treatment planning and on the first day of treatment. The intervention focuses on providing sensory and procedural information to patients and reducing …