Radiology Commons^™

Mri-Based Radiomics Model From Mesorectal Fat To Predict Perirectal Lymph Node Status And Extramural Venous Invasion In Colorectal Cancer Patients, Yaniga Swaengdee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Colorectal cancer (CRC) is the third most common cancer worldwide and the incidence rate is rising in Asia. Perirectal lymph node metastasis (PLN) and extramural venous invasion (EMVI) are common and associated with poor prognosis in CRC patients. While total mesorectal excision is the gold standard for confirming PLN and EMVI, MRI is keys modality for staging. Radiomics, a technique that extracts quantitative features from medical images, allows for the development of predictive models for PLN and EMVI. This study aimed to build and evaluate a predictive model based on mesorectal fat radiomics from MRI images to improve PLN and …

Varian Halcyon Cone Beam Computed Tomography Dose Measurement By Radiophotoluminescent Glass Dosimeter, Kantida Jittrakool

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cone beam computed tomography (CBCT) is widely used as the primary imaging method in image-guided radiation therapy. The Varian Halcyon system (Varian Medical Systems, Palo Alto, CA, USA) requires daily imaging prior to each patient’s treatment. This study focuses on comparing the radiation doses to normal organs across all available kV-CBCT protocols on the Varian Halcyon system. Radiophotoluminescent glass dosimeters (RPLGD) were used to measure doses, placed inside an Alderson Rando phantom positioned at specific anatomical sites including the head, thorax, breast, and pelvis. CBCT scans were performed using preset protocols, with no modifications to parameters. The average organ dose …

Dosimetric Comparison Between Volumetric Modulated Arc Therapy On Truebeam And Halcyon Of Boost Plan For Total Body Irradiation, Wanwanut Jaihow

Chulalongkorn University Theses and Dissertations (Chula ETD)

Total Body Irradiation (TBI) is a special treatment technique aimed at immunosuppression. The purpose of this study was to compare the dosimetric results of volumetric modulated arc therapy (VMAT) plans of TBI treatment between TrueBeam and Halcyon treatment machines. Eight TBI patients were planned by 6 MV of two lateral opposing with extended SAD technique to 5 meters to receive the prescribed dose of 1200 cGy in 6 fractions at head and legs. A single fraction boosts up the dose ranging from shoulder to mid-thigh. Plans were optimized and calculated in the Eclipse treatment planning system using VMAT by TrueBeam …

Local Diagnostic Reference Level At Nuclear Medicine Centers In Thailand And Myanmar, Yin Moe Aye

Chulalongkorn University Theses and Dissertations (Chula ETD)

Diagnostic reference level (DRL) has been an effective and practical tool in the optimization of radiation protection in medical exposure to patients. Local DRL represents the median value, or 50th percentile, of the quantity distribution of common nuclear medicine examinations. This study aims to establish LDRL at NM centers in Thailand and Myanmar. Methods: The demographic data of adult patients with body weight 45-75kg, radiation metric parameters including radiopharmaceutical administered activity (MBq), Volumetric CT dose index (CTDIvol, mGy), dose length product (DLP, mGy. cm), and scan length (cm), of SPECT, SPECT/CT, and PET/CT imaging were retrospectively collected from January 2023 …

Evaluating Dosimetric Accuracy Of Aaa And Axb Algorithms In Lung Stereotactic Body Radiation Therapy, May Thu Htet

Chulalongkorn University Theses and Dissertations (Chula ETD)

The accuracy of dose calculation in heterogeneous media is heavily influenced by the choice of dose calculation algorithm. This study aimed to compare the dosimetric performance of the Anisotropic Analytical Algorithm (AAA) and Acuros XB (AXB) in stereotactic body radiotherapy (SBRT) for lung cancer. Twenty-four lung cancer patients were divided into two groups: free breathing (FB) and deep inspiration breath hold (DIBH). For each patient, three half-arc volumetric modulated arc therapy (VMAT) plans were generated using 6 MV flattening filter-free (FFF) beams, prescribing 50 Gy in five fractions to the planning target volume (PTV), using the Eclipse Treatment Planning System. …

Tumor Prognosis In Nasopharyngeal Carcinoma Using Deep Transfer Learning With Radimagenet From Ct Images, Parida Petiraksakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nasopharyngeal carcinoma (NPC) is a common malignant tumor in Southeast Asia. It is characterized by complex anatomical features and aggressive behavior. Accurate prognosis prediction plays a crucial role in the optimization of treatment strategies and improvement of patient outcomes. Although recent advances in deep learning, particularly convolutional neural networks (CNNs), have demonstrated promising results in medical image analysis, the limited availability of annotated medical imaging datasets remains a significant challenge. Transfer learning (TL), particularly using domain-specific pretrained datasets, such as RadImageNet, offers a practical solution to this limitation. This study aimed to evaluate the effectiveness of deep transfer learning models …

Enlarged Perivascular Spaces Are A Clinically Relevant Neuroimaging Biomarker Of Cerebral Small Vessel Disease, Timothy Justin Libecap

Theses and Dissertations--Neuroscience

Vascular contributions to cognitive impairment and dementia (VCID) represents the intersection between cerebrovascular disease and cognitive decline. Cerebral small vessel disease (cSVD) is an important risk factor that may precede the onset of VCID by years. cSVD is characterized by in-vivo neuroimaging biomarkers including enlarged perivascular spaces (ePVS). PVS are the site of interchange between interstitial fluid (ISF) and cerebrospinal fluid (CSF) which is believed to play a role in the removal of brain waste. Reduced clearance may lead to enlargement of the PVS and subsequent accumulation of toxic solutes characteristic of neurodegeneration. Given the presence of ePVS in brain …

Utility Of Diagnostic Radiology Imaging Techniques In The Diagnosis And Characterization Of Saccular Aneurysm Involving The Right Internal Jugular Vein: A Case Report And Brief Review Of Literature, Javier Hernandez, Poyan Rafiei

Gulf Coast Division GME Research Symposium 2024

No abstract provided.

Radiation Induced Skin Fibrosis (Risf): Opportunity For Angiotensin Ii-Dependent Intervention, Patricia F. Boothe, Vidya P. Kumar, Yali Kong, Kan Wang, Howard Levinson, David Mu, Milton L. Brown

Department of Biomedical and Translational Sciences Faculty Publications

Medical procedures, such as radiation therapy, are a vital element in treating many cancers, significantly contributing to improved survival rates. However, a common long-term complication of such exposure is radiation-induced skin fibrosis (RISF), a complex condition that poses substantial physical and psychological challenges. Notably, about 50% of patients undergoing radiation therapy may achieve long-term remission, resulting in a significant number of survivors managing the aftereffects of their treatment. This article delves into the intricate relationship between RISF, reactive oxygen species (ROS), and angiotensin II (Ang II) signaling. It proposes the underlying mechanisms and examines potential treatments for mitigating skin fibrosis. …

Predicting Radiation-Induced Immune Suppression In Lung Cancer Patients Treated With Stereotactic Body Radiation Therapy, Jonathan Colen, Cam Nguyen, Seth W. Liyanage, Eric Aliotta, Joe Chen, Clayton Alonso, Kara Romano, Sean Peach, Timothy Showalter, Paul Read, James Larner, Krishni Wijesooriya

Data Science Faculty Publications

BACKGROUND: Stereotactic body radiation therapy (SBRT) is known to modulate the immune system and contribute to the generation of anti-tumor T cells and stimulate T cell infiltration into tumors. Radiation-induced immune suppression (RIIS) is a side effect of radiation therapy that can decrease immunological function by killing naive T cells as well as SBRT-induced newly created effector T cells, suppressing the immune response to tumors and increasing susceptibility to infections.

PURPOSE: RIIS varies substantially among patients and it is currently unclear what drives this variability. Models that can accurately predict RIIS in near real time based on treatment plan characteristics …

Novel Engineering Approaches For Orthopedic Injury Treatment And Infection Diagnosis, Cynthia Co

Bioengineering Dissertations - Archive

Bioengineering has made significant contributions to the treatment of orthopedic injury through interdisciplinary approaches. Central to these advancements are many orthopedic implants, including anchors and joint replacements, which have been designed to restore mobility. Despite their functional efficacy, these products have limited lifespan and are associated with many complications, such as implant-associated infection. The success of implant design and function, both in the short and long term, is paramount for enhancing patient outcomes and overall well-being. Therefore, my thesis work is dedicated to addressing these critical challenges, aiming to maximize their treatment effect while minimizing the implant-associated complications.

Long-term patient …

Diagnostic Utility Of Chest Radiographs In Children With Clinically Diagnosed Pneumonia As Per The Kenya Basic Paediatric Protocol, Ivy Waruguru Wakahora

Master of Medicine in Imaging and Diagnostic Radiology

Introduction; Pneumonia causes significant morbidity and mortality in children globally, emphasizing the need for accurate diagnosis. While chest radiographs have traditionally been the gold standard for diagnosis, recent international guidelines discourage their routine use in paediatric community acquired pneumonia (pCAP). Despite this, chest radiographs are still regularly acquired for pneumonia diagnosis, resulting in practice variations and imaging overutilization. This study aims to evaluate the diagnostic utility of chest radiographs in children with clinically diagnosed pneumonia as per the Kenya Basic Paediatric Protocol (KBPP).

Materials and methods: Data was retrospectively reviewed of 159 paediatric patients at Aga Khan University Hospital, Nairobi …

Machine-Learning-Enabled Diagnostics With Improved Visualization Of Disease Lesions In Chest X-Ray Images, Md. Fashiar Rahman, Tzu-Liang (Bill) Tseng, Michael Pokojovy, Peter Mccaffrey, Eric Walser, Scott Moen, Alex Vo, Johnny C. Ho

Mathematics & Statistics Faculty Publications

The class activation map (CAM) represents the neural-network-derived region of interest, which can help clarify the mechanism of the convolutional neural network’s determination of any class of interest. In medical imaging, it can help medical practitioners diagnose diseases like COVID-19 or pneumonia by highlighting the suspicious regions in Computational Tomography (CT) or chest X-ray (CXR) film. Many contemporary deep learning techniques only focus on COVID-19 classification tasks using CXRs, while few attempt to make it explainable with a saliency map. To fill this research gap, we first propose a VGG-16-architecture-based deep learning approach in combination with image enhancement, segmentation-based region …

Comprehensive Analysis Of Craniopharyngioma: Epidemiology, Clinical Characteristics, Management Strategies, And Role Of Radiotherapy, Amir Mushtaq, Mohsin Fayaz, Abdul Rashid Bhat, Abbas F Abdul Hussein, Gianluca Ferini, Giuseppe Emmanuele Umana, Gianluca Scalia, Feroze Ahmad Mir, Aizul Khursheed, Bipin Chaurasia

Faculty, Staff and Student Publications

BACKGROUND/AIM: Craniopharyngiomas pose challenges in diagnosis and management due to their rare occurrence and diverse clinical manifestations. This study aimed to provide a comprehensive analysis of cranio-pharyngioma, including its epidemiological trends, clinical presentations, radiological characteristics, surgical interventions, and the role of radiotherapy.

PATIENTS AND METHODS: A retrospective observational study was conducted on 23 patients diagnosed with craniopharyngioma at our hospital from August 2017 to July 2019. Data regarding demographics, clinical presentation, radiological findings, surgical interventions, and adjuvant therapies were collected and analyzed.

RESULTS: Craniopharyngiomas exhibited a bimodal age distribution, with peaks in childhood and late adulthood. Clinical presentations varied between …

Siglec15, Negatively Correlated With Pd-L1 In Hcc, Could Induce Cd8+ T Cell Apoptosis To Promote Immune Evasion, Zheng Chen, Mincheng Yu, Bo Zhang, Lei Jin, Qiang Yu, Shuang Liu, Binghai Zhou, Jiuliang Yan, Wentao Zhang, Xiaoqiang Li, Yongfeng Xu, Yongsheng Xiao, Jian Zhou, Jia Fan, Mien-Chie Hung, Qinghai Ye, Hui Li, Lei Guo

Faculty, Staff and Student Publications

Functional roles of SIGLEC15 in hepatocellular carcinoma (HCC) were not clear, which was recently found to be an immune inhibitor with similar structure of inhibitory B7 family members. SIGLEC15 expression in HCC was explored in public databases and further examined by PCR analysis. SIGLEC15 and PD-L1 expression patterns were examined in HCC samples through immunohistochemistry. SIGLEC15 expression was knocked-down or over-expressed in HCC cell lines, and CCK8 tests were used to examine cell proliferative ability in vitro. Influences of SIGLEC15 expression on tumor growth were examined in immune deficient and immunocompetent mice respectively. Co-culture system of HCC cell lines and …

A Look-Up-Table Development To Facilitate Ct Simulation Of Mr-Linac Treatment, Neil Hughes, Travis C Salzillo, Sastry Vedam, Tze Yee Lim, Xin Wang, He Wang, Mustefa Mohammedsaid, Clifton D Fuller, Jihong Wang, Jinzhong Yang

Faculty, Staff and Student Publications

While current MR-Linac (MRL) treatment workflows utilize a large table overlay during CT simulation to convert indexing between the two machines, we developed a look-up-table (LUT) as an alternative approach. After populating the LUT, index conversion factors were verified at three separate table locations. The resultant root-mean-square isocenter shifts on the MRL were 0.04/0.08 cm, 0.08/0.07 cm, and 0.09/0.08 cm with/without using the table overlay during simulation in the lateral, longitudinal, and vertical directions, respectively, which is within registration tolerance. Clinical implementation of the LUT has resulted in a more efficient MRL treatment workflow while maintaining accurate patient setup.

Reporting Quality Of Endoscopic Colorectal Cancer Screening Randomized Controlled Trials: Adherence To Recommendations And Interventions, Fouad Jaber, Khalid Ahmed, Osama Hamid, Willie Mohammed Johnson, Saqr Alsakarneh, Abubaker O Abdalla, Yazan Abboud, Mouhand Mohamed, Dushyant Singh Dahiya, Shifa Umar, Mohamed Abdallah, Mohammad Bilal, Aasma Shaukat

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: In 2013, the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) steering group published recommendations to standardize reporting quality in randomized controlled trials (RCTs). We aim to assess adherence to SPIRIT reporting guidelines in RCTs on endoscopic colorectal cancer (CRC) screening and participants' adherence to trial protocols.

METHODS: We searched databases for RCTs evaluating flexible sigmoidoscopy or colonoscopy for CRC screening published in English language through September 2023. Each eligible study was evaluated using the 8 core SPIRIT statement areas, totaling 51 points. Each item received 1 point if it met the criteria and 0 points if …

Clinical Acceptability Of Automatically Generated Lymph Node Levels And Structures Of Deglutition And Mastication For Head And Neck Radiation Therapy, Sean Maroongroge, Abdallah Sr Mohamed, Callistus Nguyen, Jean Guma De La Vega, Steven J Frank, Adam S Garden, Brandon G Gunn, Anna Lee, Lauren Mayo, Amy Moreno, William H Morrison, Jack Phan, Michael T Spiotto, Laurence E Court, Clifton D Fuller, David I Rosenthal, Tucker J Netherton

Faculty, Staff and Student Publications

BACKGROUND AND PURPOSE: Auto-contouring of complex anatomy in computed tomography (CT) scans is a highly anticipated solution to many problems in radiotherapy. In this study, artificial intelligence (AI)-based auto-contouring models were clinically validated for lymph node levels and structures of swallowing and chewing in the head and neck.

MATERIALS AND METHODS: CT scans of 145 head and neck radiotherapy patients were retrospectively curated. One cohort (n = 47) was used to analyze seven lymph node levels and the other (n = 98) used to analyze 17 swallowing and chewing structures. Separate nnUnet models were trained and validated using the separate …

Assessment Of Forensic And Clinical Criteria Of Orbital Blowout Fractures For Use In Bioarchaeological Analysis, Dylan E. Ornot

Honors Undergraduate Theses

Orbital blowout fractures are a particular facial fracture occurring within the inner eye orbits of the face caused by blunt force trauma to the eyeball or the lower orbital rim. This fracture is common in modern clinical contexts due to physical assaults, but examining this fracture in skeletal material can also provide insights into the patterns of interpersonal violence within the fields of bioarchaeology and forensic anthropology. Issues with analyzing this fracture in skeletal material arise due to the clinical assessment practices of blowout fractures, where medical practitioners are highly focused on the soft tissue presentations of the fracture in …

Ai And Radiologist Assessments On The Prevalence Of Tmj Osteoarthritis Using Radiographic Images: A Comparative Study, Louloua Mourad, Nayer Abo El Saad, Yehia El Mahallawy

International Arab Journal of Dentistry

Objectives: This study aims to address the significant discomfort and functional impairment associated with temporomandibular joint osteoarthritis (TMJ OA), which negatively impacts the quality of life. It emphasizes the importance of prompt diagnosis and explores the potential of an Artificial Intelligence (AI) system to enhance TMJ OA diagnosis.

Methods: The prevalence of TMJ OA was evaluated using 3 diagnostic tools: the gold standard, the AI model, and an examiner. In total, 132 patients who performed 190 cone-beam computed tomography (CBCT) images were included.

Results: The prevalence of TMJ OA was 62.11% using the gold standard, 63.68% using …