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2,330 full-text articles. Page 92 of 101.

Anatomical Variations Of Nose And Para-Nasal Sinuses; Ct Scan Review, Mohammad Adeel, Muhammad Shaheryar Ahmed Rajput, Shabbir Akhter, Mubasher Ikram, Asif Arain, Yasir Jameel Khattak 2013 Aga Khan University

Anatomical Variations Of Nose And Para-Nasal Sinuses; Ct Scan Review, Mohammad Adeel, Muhammad Shaheryar Ahmed Rajput, Shabbir Akhter, Mubasher Ikram, Asif Arain, Yasir Jameel Khattak

Section of Otolaryngology, Head & Neck Surgery

Objective: To determine the frequency of anatomic variations on computed tomography scan of para-nasal sinuses.
Methods: The retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised computed tomography scans of 77 patients who had presented between October 2007 and March 2011. All the scans were reviewed using Picture Archiving Communication System computer software. The scans were reviewed for the presence of deviated nasal septum, paradoxical middle turbinate, Haller cell, Onodi cell, and pneumatisation of the middle turbinate and uncinate process.
Results: The mean age of the patients was 31±13.15 years. One or more types of anatomical …


Assessment Of Early Tumor Response To Cytotoxic Chemotherapy With Dynamic Contrast-Enhanced Ultrasound In Human Breast Cancer Xenografts., Jian-Wei Wang, Wei Zheng, Ji-Bin Liu, Yao Chen, Long-Hui Cao, Rong-Zhen Luo, An-Hua Li, Jian-Hua Zhou 2013 State Key Laboratory of Oncology in South China, Department of Ultrasound, Sun Yat-Sen University Cancer Center

Assessment Of Early Tumor Response To Cytotoxic Chemotherapy With Dynamic Contrast-Enhanced Ultrasound In Human Breast Cancer Xenografts., Jian-Wei Wang, Wei Zheng, Ji-Bin Liu, Yao Chen, Long-Hui Cao, Rong-Zhen Luo, An-Hua Li, Jian-Hua Zhou

Department of Radiology Faculty Papers

There is a strong need to assess early tumor response to chemotherapy in order to avoid adverse effects from unnecessary chemotherapy and allow early transition to second-line therapy. This study was to quantify tumor perfusion changes with dynamic contrast-enhanced ultrasound (CEUS) in the evaluation of early tumor response to cytotoxic chemotherapy. Sixty nude mice bearing with MCF-7 breast cancer were administrated with either adriamycin or sterile saline. CEUS was performed on days 0, 2, 4 and 6 of the treatment, in which time-signal intensity (SI) curves were obtained from the intratumoral and depth-matched liver parenchyma. Four perfusion parameters including peak …


Early Results Of Prostate Cancer Radiation Therapy: An Analysis With Emphasis On Research Strategies To Improve Treatment Delivery And Outcomes., Kosj Yamoah, Kwamena Beecham, Sarah E Hegarty, Terry Hyslop, Timothy Showalter, Joel Yarney 2013 Thomas Jefferson University

Early Results Of Prostate Cancer Radiation Therapy: An Analysis With Emphasis On Research Strategies To Improve Treatment Delivery And Outcomes., Kosj Yamoah, Kwamena Beecham, Sarah E Hegarty, Terry Hyslop, Timothy Showalter, Joel Yarney

Department of Radiation Oncology Faculty Papers

ABSTRACT: BACKGROUND: There is scant data regarding disease presentation and treatment response among black men living in Africa. In this study we evaluate disease presentation and early clinical outcomes among Ghanaian men with prostate cancer treated with external beam radiotherapy (EBRT). METHODS: A total of 379 men with prostate cancer were referred to the National Center for Radiotherapy, Ghana from 2003 to 2009. Data were collected regarding patient-and tumor-related factors such as age, prostate specific antigen (PSA), Gleason score (GS), clinical stage (T), and use of androgen deprivation therapy (ADT). For patients who received EBRT, freedom from biochemical failure (FFbF) …


Neuroimaging Of A Pilocytic Astrocytoma With Anaplastic Features And Diffusion Tensor Imaging Characteristics, Lara Walkoff, Andrew J. Degnan, Mark Ghassibi, Robert V. Jones, Jonathan H. Sherman, Lucien M. Levy 2013 University of Pittsburgh

Neuroimaging Of A Pilocytic Astrocytoma With Anaplastic Features And Diffusion Tensor Imaging Characteristics, Lara Walkoff, Andrew J. Degnan, Mark Ghassibi, Robert V. Jones, Jonathan H. Sherman, Lucien M. Levy

Radiology Faculty Publications

We report the magnetic resonance imaging findings of an adult patient with a biopsy-proven pilocytic astrocytoma with anaplastic features. Pilocytic astrocytomas rarely occur in adults, and presentation with anaplastic features such as rapid mitotic activity, hypercellularity, and atypia is particularly uncommon. Accurate neuroimaging diagnosis is essential, but differentiation from more malignant neoplastic lesions may be challenging. Diffusion tensor imaging may potentially provide information on cell proliferation, vascularity, and fiber destruction, which can have implications for treatment and prognosis. In this case, tractography and fractional anisotropy maps demonstrated displacement of adjacent parenchyma and relatively intact fractional anisotropy, which is more suggestive …


Dysembryoplastic Neuroepithelial Tumor With Atypical Presentation: Mri And Diffusion Tensorcharacteristics, Kalyan Paudel, Samuel Borofsky, Robert V. Jones, Lucien M. Levy 2013 George Washington University

Dysembryoplastic Neuroepithelial Tumor With Atypical Presentation: Mri And Diffusion Tensorcharacteristics, Kalyan Paudel, Samuel Borofsky, Robert V. Jones, Lucien M. Levy

Radiology Faculty Publications

We report the neuroimaging findings of a 26-year-old female patient with a biopsy-proven dysembryoplastic neuroepithelial tumor (DNET). DNETs are an uncommon, usually benign, glial-neural cortical neoplasm of children and young adults who typically present with intractable seizures. DNETs may occur in any region of the supratentorial cortex, but have a predilection for the temporal lobes. Accurate neuroimaging diagnosis is essential since patients with DNET benefit from complete resection. However, accurate differentiation from other cortical lesions may be challenging. Typical conventional Magnetic Resonance Imaging (MRI) features can help in the differentiation from other similar cortical tumors. Diffusion tensor imaging can also …


Prostate Cancer: Can Multiparametric Mr Imaging Help Identify Patients Who Are Candidates For Active Surveillance?, B. Turkbey, H. Mani, O. Aras, J. Ho, A. Hoang, A. R. Rastinehad, H. Agarwal, V. Shah, M. Bernardo, P. L. Choyke, +8 additional authors 2013 Northwell Health

Prostate Cancer: Can Multiparametric Mr Imaging Help Identify Patients Who Are Candidates For Active Surveillance?, B. Turkbey, H. Mani, O. Aras, J. Ho, A. Hoang, A. R. Rastinehad, H. Agarwal, V. Shah, M. Bernardo, P. L. Choyke, +8 Additional Authors

Journal Articles

PURPOSE: To determine whether multiparametric magnetic resonance (MR) imaging can help identify patients with prostate cancer who would most appropriately be candidates for active surveillance (AS) according to current guidelines and to compare the results with those of conventional clinical assessment scoring systems, including the D'Amico, Epstein, and Cancer of the Prostate Risk Assessment (CAPRA) systems, on the basis of findings at prostatectomy. MATERIALS AND METHODS: This institutional review board-approved HIPAA-compliant retrospectively designed study included 133 patients (mean age, 59.3 years) with a mean prostate-specific antigen level of 6.73 ng/mL (median, 4.39 ng/mL) who underwent multiparametric MR imaging at 3.0 …


Impact Of Varied Low Resolution Phantoms On Intensity Modulated Proton Therapy Dose Distributions, Aarohi Shyam Padhye 2013 California State University, San Bernardino

Impact Of Varied Low Resolution Phantoms On Intensity Modulated Proton Therapy Dose Distributions, Aarohi Shyam Padhye

Theses Digitization Project

The primary purpose of this thesis is to discuss the usefulness of image segmentation techniques in creating accurate proton dose distribution plans. The calculation of the proton dose distribution has to take into account the material (tissue, bone, brain) in the treatment area of the patients body.


Stereotactic Localization And Targeting Accuracy For Experimental Proton Radiosurgery, Yin Chen 2013 California State University, San Bernardino

Stereotactic Localization And Targeting Accuracy For Experimental Proton Radiosurgery, Yin Chen

Theses Digitization Project

The purpose of this study was to improve an existing experimental proton radiosurgery system at Loma Linda University Medical Center to reach sub-millimeter accuracy before proton radiosurgery with narrow beams can be used in a clinical trial. Protons, different from photons (i.e., x-rays or gamma rays), are charged with particles that slow down in matter and release a burst of energy near the end of their range (maximum depth of penetration), which is called the Bragg peak, named after the physicist William Henry Bragg who discovered it in 1903. Photon beams deliver most doses over a large area near the …


Fiducial-Free Alignment Verification Techniques For Intracranial Radiosurgery, Kenneth Matthew Williams 2013 California State University, San Bernardino

Fiducial-Free Alignment Verification Techniques For Intracranial Radiosurgery, Kenneth Matthew Williams

Theses Digitization Project

This thesis serves as the basis for a method using image registration to automate patient alignment in an effort to eliminate the dependency on the fiducial markers as well as improve the accuracy efficiency of the alignment process. Proton beams are an external beam modality of radiation therapy that can be used effectively for radiosurgical applications due to the dosimetry advantage of the Bragg peak. The Bragg peak is a phenomenon exploited by proton beam therapy to concentrate the effect of the beams on the tumor while minimizing damage to critical structures and other health tissues within the patient.


A New Phantom And Gradient Isocenter Estimation For Magnetic Resonance Imaging Distortion Correction, Zongqi Cai 2013 California State University, San Bernardino

A New Phantom And Gradient Isocenter Estimation For Magnetic Resonance Imaging Distortion Correction, Zongqi Cai

Theses Digitization Project

The purpose of this study was to develop and implement a numerical software based method that can accurately correct the distortion of MR images generated by 3T MRI scanner. To accomplish this, a new phantom has been designed from scratch to capture the distortions inside 3T MRI scanner. An algorithm has been developed, based on the unique geometric feature of the new phantom, to estimate the location of gradient isocenter of the magnetic field inside 3T MRI scanner for the first time.


Alternative Hull Detection Techniques For Preprocessing In Proton Computed Tomography Reconstruction, Blake Edward Schultze 2013 California State University, San Bernardino

Alternative Hull Detection Techniques For Preprocessing In Proton Computed Tomography Reconstruction, Blake Edward Schultze

Theses Digitization Project

The purpose of this study was to develop computationally efficient hull detection techniques appropriate for image reconstruction using sparse matrices. The hull detection techniques investigated were space carving (SC), modified space carving (MSC), and space modeling (SM) and these were compared to the cone-beam version of filtered back projection (FBP) algorithm in terms of their computation time and the quality of the object hull they produced.


A Feasibility Study Using Tomodirect For Craniospinal Irradiation, Ulrich W. Langner, Janelle A. Molloy, John F. Gleason Jr., Jonathan M. Feddock 2013 University of Kentucky

A Feasibility Study Using Tomodirect For Craniospinal Irradiation, Ulrich W. Langner, Janelle A. Molloy, John F. Gleason Jr., Jonathan M. Feddock

Radiation Medicine Faculty Publications

The feasibility of delivering craniospinal irradiation (CSI) with TomoDirect is investigated. A method is proposed to generate TomoDirect plans using standard three-dimensional (3D) beam arrangements on Tomotherapy with junctioning of these fields to minimize hot or cold spots at the cranial/spinal junction. These plans are evaluated and compared to a helical Tomotherapy and a three-dimensional conformal therapy (3D CRT) plan delivered on a conventional linear accelerator (linac) for CSI. The comparison shows that a TomoDirect plan with an overlap between the cranial and spinal fields might be preferable over Tomotherapy plans because of decreased low dose to large volumes of …


Retro-Aortic Left Renal Vein, JoAnn Aichroth, RDMS, Traci B. Fox, MS, RT(R), RDMS, RVT 2013 Thomas Jefferson University

Retro-Aortic Left Renal Vein, Joann Aichroth, Rdms, Traci B. Fox, Ms, Rt(R), Rdms, Rvt

Department of Radiologic Sciences Faculty Papers

The term retro-aortic left renal vein (RLRV) is defined as the left renal vein coursing posterior to the abdominal aorta. RLRV is an uncommon condition in which the left renal vein passes posterior to the abdominal aorta and anterior to the vertebrae. RLRV may lead to left renal vein hypertension (LRVH) syndrome, which is also known as Nutcracker syndrome. Nutcracker syndrome (NCS) is a condition in which the left renal vein is compressed causing hypertension of the vessel. RLRV and Nutcracker syndrome are vascular anomalies considered to be of clinical importance especially during surgical procedures of the renal vasculature.


Embolization With Histoacryl Glue Of An Anastomotic Pseudoaneurysm Following Surgical Repair Of Abdominal Aortic Aneurysm, Ayesha Walid, Tanveer Ul Haq, Raza Sayani, Zia Ur Rehman 2013 Aga Khan University

Embolization With Histoacryl Glue Of An Anastomotic Pseudoaneurysm Following Surgical Repair Of Abdominal Aortic Aneurysm, Ayesha Walid, Tanveer Ul Haq, Raza Sayani, Zia Ur Rehman

Department of Radiology

We report a 62-year-old female who had surgical repair of abdominal aortic aneurysm with a bifurcated graft 2 years ago. She presented with a distal anastomotic pseudoaneurysm which was successfully embolized with histoacryl glue. Only one such similar case has been reported in the literature so far (Yamagami et al. (2006)).


Role Of Ultrasound In Characterization Of Ovarian Masses, Saima Hafeez, Saira Sufian, Quratulain Merchant, Yasir Jamil, Imrana Masroor 2013 Aga Khan University

Role Of Ultrasound In Characterization Of Ovarian Masses, Saima Hafeez, Saira Sufian, Quratulain Merchant, Yasir Jamil, Imrana Masroor

Department of Radiology

Background: Ovarian cancer is the second most common malignancy in Pakistani women, accounting for 4% of all cancers in the female population. The aim of this study was to determine sensitivity, specificity, positive and negative predictive values and 95% confidence intervals for ultrasound in characterization of ovarian masses in patients presenting at public and private tertiary care hospitals in Karachi, Pakistan.MATERIALS AND Methods: We adopted a cross-sectional analytical study design to retrospectively collect data from January 2009-11 from medical records of two tertiary care hospitals. Using a non-probability purposive sampling technique, we recruited a sample of 86 women aged between …


Ovarian Masses: Is Multi-Detector Computed Tomography A Reliable Imaging Modality?, Yasir Jamil, Saima Hafeez, Tariq Alam, Madiha Beg, Mohammad Awais, Imrana Masroor 2013 Agha Khan University

Ovarian Masses: Is Multi-Detector Computed Tomography A Reliable Imaging Modality?, Yasir Jamil, Saima Hafeez, Tariq Alam, Madiha Beg, Mohammad Awais, Imrana Masroor

Department of Radiology

Background: Ovarian cancer continues to pose a major challenge to physicians and radiologists. It is the third most common gynecologic malignancy and estimated to be fifth leading cancer cause of death in women, constituting 23% of all gynecological malignancies. Multi-detector computed tomography (MDCT) appears to offer an excellent modality in diagnosing ovarian cancer based on combination of its availability, meticulous technique, efficacy and familiarity of radiologists and physicians. The aim of this study was to compute sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of 64- slice MDCT in classifying ovarian masses; 95% confidence intervals were reported.MATERIALS AND …


Potential For High Resolution Microscintigraphy Using Polycapillary Optics, Patrick Richard Conlon 2013 University at Albany, State University of New York

Potential For High Resolution Microscintigraphy Using Polycapillary Optics, Patrick Richard Conlon

Legacy Theses & Dissertations (2009 - 2024)

Scintigraphy, also known as nuclear imaging, is the process of imaging an object that has been labeled with a radioactive material. A novel technique employing polycapillary optics for very high - resolution scintigraphy is presented. The small channel size and angular selectivity of polycapillary optics allow them to act as multiple-hole collimators and be used with high - resolution detectors. The ability of the optics to work with high resolution detectors allow the system to discriminate against scatter, thus negating the need for energy sensitive detectors, which are known to have poor resolution. Therefore the use of polycapillary optics presents …


An Edge-Directed Interpolation Method For Fetal Spine Mr Images, Shaode Yu, Rui Zhang, Shibin Wu, Jiani Hu, Yaoqin Xie 2013 Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences

An Edge-Directed Interpolation Method For Fetal Spine Mr Images, Shaode Yu, Rui Zhang, Shibin Wu, Jiani Hu, Yaoqin Xie

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Fetal spinal magnetic resonance imaging (MRI) is a prenatal routine for proper assessment of fetus development, especially when suspected spinal malformations occur while ultrasound fails to provide details. Limited by hardware, fetal spine MR images suffer from its low resolution.

High-resolution MR images can directly enhance readability and improve diagnosis accuracy. Image interpolation for higher resolution is required in clinical situations, while many methods fail to preserve edge structures. Edge carries heavy structural messages of objects in visual scenes for doctors to detect suspicions, classify malformations and make correct diagnosis. Effective interpolation with well-preserved edge structures is still …


Controversies About Radioactive Iodine-131 Remnant Ablation In Low Risk Thyroid Cancers: Are We Near A Consensus?, Maseeh Uz Zaman, Nosheen Fatima, Ajit Kumar Padhy, Unaiza Zaman 2013 Aga Khan University

Controversies About Radioactive Iodine-131 Remnant Ablation In Low Risk Thyroid Cancers: Are We Near A Consensus?, Maseeh Uz Zaman, Nosheen Fatima, Ajit Kumar Padhy, Unaiza Zaman

Department of Radiology

Well differentiated thyroid cancers (WDTC), including papillary (80%) and follicular (10%) types, are the most common endocrine cancers globally. Over the last few decades most the diagnosed cases have fallen into low risk categories. Radioactive iodine-131 (RAI) has an established role in reducing recurrence and improving the survival in high risk patients. In patients with primary tumor size <1 >cm, RAI is not recommended by many thyroid societies. However, low risk WDTC has been an arena of major controversies, most importantly the role and dose of adjuvant RAI for remnant ablation to minimize chances of recurrence and improving survival. This review …


Treatment Of Nonvariceal Gastrointestinal Hemorrhage By Transcatheter Embolization, Muhammad Ali, Tanveer Ul Haq, Basit Salam, Madiha Beg, Raza Sayani, Muhammad Azeemuddin 2013 Aga Khan University

Treatment Of Nonvariceal Gastrointestinal Hemorrhage By Transcatheter Embolization, Muhammad Ali, Tanveer Ul Haq, Basit Salam, Madiha Beg, Raza Sayani, Muhammad Azeemuddin

Department of Radiology

Purpose. To investigate the sensitivity of mesenteric angiography, technical success of hemostasis, clinical success rate, and complications of transcatheter embolization for the treatment of acute nonvariceal gastrointestinal hemorrhage. Material and Methods. A retrospective review of 200 consecutive patients who underwent mesenteric arteriography for acute nonvariceal gastrointestinal hemorrhage between February 2004 and February 2011 was done. Results. Of 200 angiographic studies, 114 correctly revealed the bleeding site with mesenteric angiography. 47 (41%) patients had upper gastrointestinal hemorrhage and 67 (59%) patients had lower gastrointestinal hemorrhage. Out of these 114, in 112 patients (98%) technical success was achieved with immediate cessation of …


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