Medical Specialties Commons^™

Dosimetric Comparison Between Single-Energy Ct And Dual-Energy Ct For Relative Stopping Power Estimation In Proton Therapy, Thamonwan Chirdchid

Chulalongkorn University Theses and Dissertations (Chula ETD)

In proton therapy treatment planning, dose calculation requires CT calibration curve by relating CT number (HU) to relative stopping power to water (RSP). The CT calibration curve and the RSP validation are described for single-energy CT (SECT) and dual-energy CT (DECT). The focus of this work was given on the dosimetric comparison of treatment plans between SECT and DECT-based dose calculation. The 062M CIRS phantom was scanned to access the HU values by GE kVp switching method with single-energy of 120 kVp and dual-energy of 80/140 kVp. The CT calibration curve was generated using the stoichiometric calibration method and implemented …

Tolerance Levels On Dose And Anatomic Variation For Adaptive Radiotherapy Based On Statistical Process Control For Nasopharyngeal Cancer, Rudjaya Intaprom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nasopharyngeal cancer (NPC) is one of the most common cancers in Thailand and worldwide. During the long course of treatment, patients often change of anatomy in both the shape and the volume. The deviation of the delivered dose has long been a clinical concern. Adaptive radiotherapy (ART) technique is a treatment process that prevents the dose changes to clinical target volume (CTV) and organs at risk (OARs). The purpose of this study was proposed to method to set the action levels for replanning in NPC and to evaluate the dose differences of CTV and OARs by planning CT and weekly …

The Study Of Local Diagnostic Reference Levels Of Computed Tomography Procedures At Phramongkutklao Hospital, Sutasinee Mahasub

Chulalongkorn University Theses and Dissertations (Chula ETD)

Computed Tomography (CT) is a medical modality of 3D imaging technique using the X-ray photons rotate, transmit and detect the radiation by the multi-detectors. The CT examination results in the higher patient dose than the general radiography. The objective of this study was to establish the Local DRLs of patient radiation dose in CT procedures at Phramongkutklao Hospital. This study is a retrospective analysis at a single center from January-August 2021. Two CT scanners: 160 slices MDCT manufactured by Canon, model AquilionTM Prime and 640 slices MDCT manufactured by Canon, model AquilionTM One Prism have been used to collect the …

Automated Method Of Corrected Effective Diameter For Ssde In Thoracic Imaging Ct Using Cnn, Sakultala Ruenjit

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to automatically determine the corrected effective diameter (Deffcorr) using convolutional neural network (CNN) for simplified SSDE calculation in thoracic CT. Transaxial images of 108 adult patients underwent thoracic CT without contrast at King Chulalongkorn Memorial Hospital (KCMH) were collected. To calculate the Deffcorr according to Mihailidis et al., the average relative electron densities for lung tissue (ρelung=0.3), for other tissues (ρetissue=1.0) and for bone (ρebone=1.2) were employed to correct the lateral and anteroposterior dimension. The CNN network architecture based on the U-Net algorithm was used for automated image segmentation. The 108 thoracic CT images and generated segmentation …

The Psychological Impact Of The Covid-19 Outbreak On Pregnancy And Mother-Infant Prenatal Bonding, Muhammad O Awiwi, Khaled M Elsayes, Yehia I Mohamed, Lina Altameemi, Migena Gjoni, Omayr Muhammad Irshad, Ahmed Sayed Ahmed, Ahmad O Kaseb, Usama Salem

Faculty, Staff and Student Publications

PURPOSE: To identify prognostic clinical and radiologic features in patients with unresectable hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab.

PATIENTS AND METHODS: Clinical and imaging records of patients with unresectable HCC were retrospectively reviewed, and baseline features were recorded. Patients' records and imaging studies were used to determine the patients' overall survival (OS) and progression-free survival (PFS). Univariate and multivariate analyses were performed to determine prognostic features. Subanalyses of treatment-naïve patients (who never received local or systemic therapy) and previously treated patients were also performed.

RESULTS: Fifty-five patients were included in the final analysis, 23 (41.8%) of whom were …

Modeling Of Patient-Specific Periaortic Mechanics And Pulmonary Artery Hemodynamics Based On Phase-Contrast Magnetic Resonance Imaging Sequences., Johane H. Bracamonte

Theses and Dissertations

Inverse modeling in cardiovascular medicine is a collection of methodologies that can provide non-invasive patient-specific estimations of clinical risk factors using medical imaging as inputs. Its incorporation into clinical practice has the potential to improve diagnosis and treatment planning with low associated risks and costs.

Herein, three different phase contrast magnetic resonance imaging (MRI) modalities were implemented as input data, displacement encoding with stimulated echoes (DENSE MRI) applied, and time-resolved velocity encoding phase-contrast MRI, in 1D and 3D, applied to pulmonary artery (PA) hemodynamics.

A model to account for the effect of periaortic interactions due to static and dynamic structures …

Three-Dimensional (3d) Anatomic Location, Extension, And Timing Of Severe Osteoradionecrosis Of The Mandible, Lucas G Sapienza, Justin J Thomas, Weiyuan Mai, Alexander N Hanania, Sandeep Hunjan, Vlad C Sandulache, Albert C Chen

Faculty, Staff and Students Publications

BACKGROUND: The purpose of this study was to describe the topography, extension (volume), and timing of severe osteoradionecrosis (ORN) that required mandible resection in patients previously treated for head and neck cancer at a high-volume Veterans Affairs Medical Center.

MATERIALS AND METHODS: The records from a reference hyperbaric oxygen clinic were retrospectively analyzed (n = 50, 2018-2021). Inclusion criteria were: I) severe ORN defined as progressive ORN that required resection; II) pathologic confirmation of ORN; and III) availability of pre-operative CT-imaging. Using a radiotherapy (RT) imaging software, we performed a detailed volumetric (3D) analysis of the bone involvement by ORN. …

Factors Associated With Mammographic Breast Density Among Women In Karachi Pakistan, Uzma Shamsi, Shaista Afzal Saeed, Azra Shamsi, Syed Iqbal Azam, David Callen

Community Health Sciences

Background: There are no studies done to evaluate the distribution of mammographic breast density and factors associated with it among Pakistani women.
Methods: Participants included 477 women, who had received either diagnostic or screening mammography at two hospitals in Karachi Pakistan. Mammographic breast density was assessed using the Breast Imaging Reporting and Data System. In person interviews were conducted using a detailed questionnaire, to assess risk factors of interest, and venous blood was collected to measure serum vitamin D level at the end of the interview. To determine the association of potential factors with mammographic breast density, multivariable polytomous logistic …

Resting-State Functional Mri Metrics In Patients With Chronic Mild Traumatic Brain Injury And Their Association With Clinical Cognitive Performance., Faezeh Vedaei, Andrew B. Newberg, Md, Mahdi Alizadeh, Jennifer Muller, Shiva Shahrampour, Devon Middleton, Ms, George Zabrecky, Nancy Wintering, Anthony J. Bazzan Md, Daniel A. Monti, Md, Feroze Mohamed, Phd

Department of Radiology Faculty Papers

Mild traumatic brain injury (mTBI) accounts for more than 80% of people experiencing brain injuries. Symptoms of mTBI include short-term and long-term adverse clinical outcomes. In this study, resting-state functional magnetic resonance imaging (rs-fMRI) was conducted to measure voxel-based indices including fractional amplitude of low-frequency fluctuation (fALFF), regional homogeneity (ReHo), and functional connectivity (FC) in patients suffering from chronic mTBI; 64 patients with chronic mTBI at least 3 months post injury and 40 healthy controls underwent rs-fMRI scanning. Partial correlation analysis controlling for age and gender was performed within mTBI cohort to explore the association between rs-fMRI metrics and neuropsychological …

Typical Sounding Atypical Diagnostic Conundrum -- A Rare Case Of Mycobacterium Avium Complex (Mac) Presenting With Multiple Cranial Nerve Involvement, Ashwini Kini, Karl Echiverri, Edward J. Escott, Padmaja Sudhakar

Neurology Faculty Publications

Background

MAC infections rarely cause symptomatic systemic infection in immunocompetent healthy individuals. This case brings to light a rare such presentation that gives us a learning point about keeping a strong pre-clinical suspicion for this condition in patients whom lung imaging reveals suspicious cavitary lesions. Starting empiric therapy while awaiting culture results may be considered after weighing risks and benefits in order to achieve the morbidity and mortality associated with the disease.

Case report

A 54 year-old white male presented for evaluation of progressively worsening vertigo, imbalance, vertical diplopia, facial diplegia, bilateral hyperacusis followed by hearing loss, dysphagia, and dysarthria …

Can Activated Titanium Interbody Cages Accelerate Or Enhance Spinal Fusion? A Review Of The Literature And A Design For Clinical Trials, Nathaniel Toop, Connor Gifford, Rouzbeh Motiei-Langroudi, Arghavan Farzadi, Daniel Boulter, Reza Forghani, H. Francis Farhadi

Neurosurgery Faculty Publications

While spinal interbody cage options have proliferated in the past decade, relatively little work has been done to explore the comparative potential of biomaterial technologies in promoting stable fusion. Innovations such as micro-etching and nano-architectural designs have shown purported benefits in in vitro studies, but lack clinical data describing their optimal implementation. Here, we critically assess the pre-clinical data supportive of various commercially available interbody cage biomaterial, topographical, and structural designs. We describe in detail the osteointegrative and osteoconductive benefits conferred by these modifications with a focus on polyetheretherketone (PEEK) and titanium (Ti) interbody implants. Further, we describe the rationale …

Endovascular Approach In The Management Of Idiopathic Myointimal Hyperplasia Of The Inferior Mesenteric Vein, Yash B Shah, Derek Lee, Tamim S Khaddash

Department of Medicine Faculty Papers

Background: Idiopathic myointimal hyperplasia of the mesenteric vein (IMHMV) is a rare, often undiagnosed pathology affecting the colon. Patients typically present with severe abdominal pain and inflammation caused by smooth muscle proliferation of the veins, leading to arterialization, stenosis, and potential occlusion. The etiology remains unclear, but it has been hypothesized that an arteriovenous connection may be associated with the pathology. This is the first reported case indicating such an association. This case additionally highlights the potential utility of endovascular treatment, as endovascular embolization is generally a less invasive alternative to surgical resection in the treatment of such vascular disorders. …

Lung Cancer Screening: An Evidence-Based Practice Change Project, Robert Bland

Student Scholarly Projects

Practice Problem: Lung cancer is the leading cause of global cancer deaths and is a significant health issue in the US, claiming more than 155,000 lives each year. Lung cancer screening through low dose computed tomography (LDCT) can reduce lung cancer mortality by 20 percent but unfortunately, lung cancer screening is underutilized.

PICOT Question: The PICOT question that guided this project was: in a patient population eligible for LDCT lung screening (P), how does auditing of practice with feedback to the providers (I), compared to not doing the interventions as mentioned above (C), increase LDCT lung cancer screenings in the …

The Transition To Peer Learning, C. G. Roth, H. V. Naringrekar, A. E. Flanders

Department of Radiology Posters

Problem Description: Historically, peer review has been compelled by regulatory and legislative mandates, such as the Joint Commission Ongoing Professional Practice Evaluation (OPPE) requirement and the Health Care Quality Improvement Act (HCQIA) enacted by Congress in 1986. [1] However, these external mandates were focused on quality assurance, generally carrying punitive connotations and practically translated into rote compliance without the benefit of learning and improvement. In fact, the lack of quality improvement focus prompted the Institute of Medicine (IOM) to release its 2015 report, “Improving Diagnosis in Health Care,” stating that a “critical type of error in health care—diagnostic error—has received …

Imaging And Treatment Of Posttraumatic Ankle And Hindfoot Osteoarthritis, Tetyana Gorbachova, Yulia V. Melenevsky, L. Daniel Latt, Jennifer S. Weaver, Mihra S. Taljanovic

Department of Radiology Faculty Papers

Posttraumatic osteoarthritis of the ankle and hindfoot is a common and frequently debil-itating disorder. 70% to 90% of ankle osteoarthritis is related to prior trauma that encompasses a spectrum of disorders including fractures and ligamentous injuries that either disrupt the articular surface or result in instability of the joint. In addition to clinical evaluation, imaging plays a sub-stantial role in the treatment planning of posttraumatic ankle and hindfoot osteoarthritis. Imaging evaluation must be tailored to specific clinical scenarios and includes weight bearing radiography that utilizes standard and specialty views, computed tomography which can be performed with a standard or a …

Contrast-Enhanced Ultrasound Of Muscle Perfusion May Indicate Patient Response To Left Ventricular Assist Device Therapy., Lauren J. Delaney, Kathleen Fitzgerald, Maria Stanczak, Priscilla Machado, John W..C. Entwistle, Flemming Forsberg, Gordon R. Reeves

Department of Radiology Faculty Papers

PURPOSE: Left ventricular assist device (LVAD) support is associated with peripheral vascular abnormalities beyond those associated with heart failure (HF). These abnormalities are associated with persistent functional impairments that adversely impact quality of life (QoL). Methods for measuring peripheral vascular function in this population are needed.

METHODS: This pilot study investigated the use of contrast-enhanced ultrasound (CEUS) using standardized protocols to estimate changes in peripheral (quadriceps) muscle perfusion among patients with HF (INTERMACS profile 3) undergoing LVAD implantation (n = 7). Patients were then stratified by those who did ("responders", n = 4) and did not ("nonresponders", n = 3) …

Current And Future Directions Of Breast Mri, Margaret Houser, David Barreto, Anita Mehta, Rachel F. Brem

Radiology Faculty Publications

No abstract provided.

Statistical Measurements Of Dispersion Measure Fluctuations Of Frbs, Siyao Xu, David H. Weinberg, Bing Zhang

Physics & Astronomy Faculty Research

Extragalactic fast radio bursts (FRBs) have large dispersion measures (DMs) and are unique probes of intergalactic electron density fluctuations. By using the recently released First CHIME/FRB Catalog, we reexamined the structure function (SF) of DM fluctuations. It shows a large DM fluctuation similar to that previously reported in Xu & Zhang, but no clear correlation hinting toward large-scale turbulence is reproduced with this larger sample. To suppress the distortion effect from FRB distances and their host DMs, we focus on a subset of CHIME catalog with DM < 500 pc cm-3. A trend of nonconstant SF and nonzero correlation function (CF) at angular separations θ less than 10 is seen, but with large statistical uncertainties. The difference found between SF and that derived from CF at θ ≲ 10 can be ascribed to the large statistical uncertainties or the density inhomogeneities on scales on the order of 100 Mpc. The possible correlation of electron density fluctuations and inhomogeneities of density distribution should be tested when several thousands of FRBs are available.

Bilateral Popliteal Entrapment Syndrome In A Young Athlete Diagnosed With Ultrasound, Hanna K. Thompson, Justin R. Montgomery, Paul J. Spicer

Radiology Faculty Publications

Popliteal artery entrapment syndrome (PAES) occurs when the popliteal artery is compressed by abnormally developed or hypertrophied muscles adjacent to the popliteal fossa. When symptomatic, it most frequently presents with leg cramping while walking or running. We describe the case of an 18-year-old female runner presenting with claudication and exercise intolerance. After MRI was non-diagnostic, diagnostic ultrasound demonstrated that she had functional (Type VI) PAES. She subsequently underwent popliteal artery release surgery. Type VI PAES should be considered in young, healthy patients who present with claudication, particularly athletes.

Multi-Vendor And Multisite Evaluation Of Cerebrovascular Reactivity Mapping Using Hypercapnia Challenge, Peiying Liu, Dengrong Jiang, Marilyn Albert, Christopher E. Bauer, Arvind Caprihan, Brian T. Gold, Steven M. Greenberg, Karl G. Helmer, Kay Jann, Gregory A. Jicha, Pavel Rodriguez, Claudia L Satizabal, Sudha Seshadri, Herpreet Singh, Jeffrey F. Thompson, Danny J. J. Wang, Hanzhang Lu

Neuroscience Faculty Publications

Cerebrovascular reactivity (CVR), which measures the ability of cerebral blood vessels to dilate or constrict in response to vasoactive stimuli such as CO2 inhalation, is an important index of the brain's vascular health. Quantification of CVR using BOLD MRI with hypercapnia challenge has shown great promises in research and clinical studies. However, in order for it to be used as a potential imaging biomarker in large-scale and multi-site studies, the reliability of CO2-CVR quantification across different MRI acquisition platforms and researchers/raters must be examined. The goal of this report from the MarkVCID small vessel disease biomarkers consortium is to evaluate …

Alterations In Functional Connectivity Measured By Functional Magnetic Resonance Imaging And The Relationship With Heart Rate Variability In Subjects After Performing Orgasmic Meditation: An Exploratory Study, Andrew B. Newberg, Nancy Wintering, Chloe Hriso, Faezeh Vedaei, Marie Stoner, Reneita Ross

Department of Radiology Faculty Papers

Background: We measured changes in resting brain functional connectivity, with blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI), associated with a creative meditation practice that is augmented by clitoral stimulation and is designed to not only achieve a spiritual experience but to help individuals manage their most intimate personal relationships. Briefly, the meditative state is attained by both the male and female participants while the male stimulates the woman's clitoris. The goal of this practice, called orgasmic meditation (OM), according to the practitioners is not sexual, but to use the focus on clitoral stimulation to facilitate a meditative …

Cessation And Resumption Of Elective Neurointerventional Procedures During The Coronavirus Disease 2019 Pandemic And Future Pandemics, Tim W. Malisch, Sameer A. Ansari, Gary R. Duckwiler, Kyle M. Fargen, Steven W. Hetts, Franklin A. Marden, Athos Patsalides, Clemens M. Schirmer, Allan Brook, Justin F. Fraser

Neurosurgery Faculty Publications

At the time of this writing, the coronavirus disease 2019 pandemic continues to be a global threat, disrupting usual processes, and protocols for delivering health care around the globe. There have been significant regional and national differences in the scope and timing of these disruptions. Many hospitals were forced to temporarily halt elective neurointerventional procedures with the first wave of the pandemic in the spring of 2020, in order to prioritize allocation of resources for acutely ill patients and also to minimize coronavirus disease 2019 transmission risks to non-acute patients, their families, and health care workers. This temporary moratorium on …

Acr Appropriateness Criteria® Parathyroid Adenoma., David Zander, Paul M Bunch, Bruno Policeni, Amy F Juliano, Denise Carneiro-Pla, Prachi Dubey, Maria K Gule-Monroe, Mari Hagiwara, Jenny K Hoang, Vikas Jain, Lawrence T Kim, Gul Moonis, Matthew S Parsons, Tanya J Rath, Carmen C Solórzano, Rathan M Subramaniam, M Reza Taheri, Kate Duchene Thoma, Andrew T Trout, Mark E Zafereo, Amanda S Corey

Radiology Faculty Publications

No abstract provided.

Acr Appropriateness Criteria® Staging And Follow-Up Of Primary Vaginal Cancer., Aoife Kilcoyne, Ravi V Gottumukkala, Stella K Kang, Esma A. Akin, Carlin Hauck, Nicole M Hindman, Chenchan Huang, Namita Khanna, Rajmohan Paspulati, Gaiane M Rauch, Tamer Said, Atul B Shinagare, Erica B Stein, Aradhana M Venkatesan, Katherine E Maturen

Radiology Faculty Publications

No abstract provided.

The Radiological Presentation Of Rasmussen Aneurysm Secondary To Pulmonary Tuberculosis And Covid-19: A Case Report, Adnan Arif, Khurram Khaliq Bhinder, Azza Sarfraz, Zouina Sarfraz, Miguel Felix, Ivan Chérrez-Ojeda

Department of Paediatrics and Child Health

Rasmussen aneurysm is rare diagnosis occurring in patients with long-standing tuberculosis. TB-COVID-19 co-infection in the context of Rasmussen aneurysm is a rare occurrence, yet new cases are emerging. An elderly male was recently diagnosed with TB-COVID-19 co-infection and presented with sudden onset massive hemoptysis. The patient was diagnosed with Rasmussen aneurysm after being evaluated by computed tomography pulmonary angiogram due to a suggestive clinical presentation. Interventional radiologists planned for embolization of pulmonary artery, with an unidentifiable source. It was suspected that the patient's source of bleeding was hampered due to local tamponade effect or thrombosis of the aneurysm. The patient …

Lipomatous Infiltration In Tuberous Sclerosis Complex - A Case Series And Literature Review., Mohammed Ilyas, Julio Quezada, Erin K. Opfer

Manuscripts, Articles, Book Chapters and Other Papers

Diffuse Lipomatosis is a dermatological lesion consisting of a poorly circumscribed, infiltrative overgrowth of mature adipose tissue that usually affects the trunk and the extremities. The lesions in the Tuberous Sclerosis Complex (TSC) are usually hamartomatous in nature, but lesions arising from adipocytes are rare. There are only three previous reports of association of TSC with diffuse lipomatosis. Herein we present a case series of diffuse lipomatosis in three subjects with TSC and proceed to review the literature for any other reported cases. On the basis of the three index cases and identification of three more cases in the literature, …

Multipara With Utero-Vesical Fistula Following Repeat Cesarean Section: A Rare Iatrogenic Complication, Gulnaz Shafqat, Anam Khan, Salma Azam, Rehana Murad

Department of Radiology

Utero-Vesical fistulas are the rarest of all urogenital fistulas, with most cases occurring after cesarean section. Its prevalence is increasing worldwide because of the increasing indications of cesarean section. Patient usually presents with urine leak, amenorrhea and cyclic hematuria. Herein, we present a case of patient presenting with complain of severe urinary tract infection following cesarean section. Review and update of recent literature regarding the diagnostic imaging of this entity are described.

Hepatocellular Carcinoma With Extrahepatic Blood Supply From Right Renal Artery, Amir Humza Sohail, Ahmad Musa, Muhammad Salman Khan, Hassan Raza Hashmi, Basit Salam, Collin E M. Brathwaite

Department of Radiology

Extrahepatic blood supply is seen in around 17-27% of hepatocellular carcinoma lesions. Evidence suggests that this extrahepatic supply most commonly originates from a right intercostal artery (70-83%) followed by left intercostal, omental and right renal arteries. Thus a comprehensive knowledge of variations in standard vascular anatomy and cognisance of factors influencing or predicting extrahepatic blood supply in HCC is instrumental in ensuring the success of surgical and interventional procedures. We present the unusual case of a 66-year-old male with HCC in Segment I of the liver with aberrant blood supply from the right renal artery in the absence of any …

Diagnostic Accuracy Of Ultrasonography For Rotator Cuff Tears: A Systematic Review And Meta-Analysis, Ali S Farooqi, Alexander Lee, David Novikov, Ann Marie Kelly, Xinning Li, John D Kelly, Robert L Parisien

Department of Medicine Faculty Papers

Background: With recent improvements in transducer strength, image resolution, and operator training, ultrasound (US) provides an excellent alternative imaging modality for the diagnosis of rotator cuff tears.

Purpose: To evaluate the diagnostic accuracy of US for partial- and full-thickness rotator cuff tears and biceps tendon tears, compare diagnostic values with those of magnetic resonance imaging (MRI) using arthroscopy as the reference standard, assess longitudinal improvements in accuracy, and compare diagnostic values from operators with different training backgrounds.

Study Design: Systematic review; Level of evidence, 3.

Methods: The PubMed and Cochrane Library databases were systematically searched for full-text journal articles published …

A Curriculum Model For Multidisciplinary Training Of Midwife Sonographers In A Low Resource Setting, Sudhir Vinayak, Marleen Temmerman, Geert Villeirs, Sharon M. Brownie

Imaging & Diagnostic Radiology, East Africa

In many low-resource settings, less than 5% of pregnant women can access ultrasound during pregnancy. Thus, gestational age is often difficult to determine, multiple pregnancies are diagnosed late and foetal and pregnancy-related anomalies can go undetected. A pilot solution was designed beyond the traditional approach of increasing numbers of qualified radiologists, gynaecologists and sonographers. An innovative Human Resource for Health (HRH) task sharing, and maternal child health (MCH) workforce training and capacity building initiative was designed, involving development and testing of a curriculum to train midwife sonographers via a teleradiology innovation platform and a partnership between specialist radiologists, sonographers and …