Radiology 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 …

The Pathology Fellowship Application Crisis: The Current State And Suggestions For Remediation, Amanda C Herrmann, Cheryl Hanau, Donald Karcher, Douglas C Miller, Alexandra Murtha, Ashley E Sanders, Charles Timmons, Karen L Kaul

Faculty, Staff and Student Publications

Problems within the Pathology fellowship application process in the US have been recognized and reported for years. Recently, members of the Graduate Medical Education Committee (GMEC) of the Association of Pathology Chairs (APC) and collaborators collected survey data from the residents themselves and the fellowship programs, as represented by both the fellowship program directors (members of the Fellowship Directors Ad Hoc Committee, FDAHC) and the program administrators (members of the Graduate Medical Education Administrators Section, GMEAS). These data are presented and discussed, and potential steps to resolve some of the problems around fellowship applications in pathology are presented.

Radiographic Findings And Association With Clinical Severity And Outcomes In Critically Ill Patients With Covid-19, Wei Wu, Pavan K Bhatraju, Natalie Cobb, Neha A Sathe, Kevin I Duan, Kevin P Seitz, Matthew R Thau, Clifford C Sung, Daniel S Hippe, Gautham Reddy, Sudhakar Pipavath

Faculty, Staff and Student Publications

PURPOSE: To describe evolution and severity of radiographic findings and assess association with disease severity and outcomes in critically ill COVID-19 patients.

MATERIALS AND METHODS: This retrospective study included 62 COVID-19 patients admitted to the intensive care unit (ICU). Clinical data was obtained from electronic medical records. A total of 270 chest radiographs were reviewed and qualitatively scored (CXR score) using a severity scale of 0-30. Radiographic findings were correlated with clinical severity and outcome.

RESULTS: The CXR score increases from a median initial score of 10 at hospital presentation to the median peak CXR score of 18 within a …

Detecting Primary Progressive Aphasia Atrophy Patterns: A Comparison Of Visual Assessment And Quantitative Neuroimaging Techniques, Stephanie Franczak, Jessica Pommy, Greta Minor, Chandler Zolliecoffer, Manav Bhalla, Mohit Agarwal, Andrew Nencka, Yang Wang, Andrew Klein, Darren O'Neill, Jude Henry, Glass Umfleet

Faculty, Staff and Student Publications

BACKGROUND: There are now clinically available automated MRI analysis software programs that compare brain volumes of patients to a normative sample and provide

OBJECTIVE: To address this gap in the literature, we examined Neuroreader

METHODS: lvPPA or aMCI patients who underwent MRI with Neuroreader

RESULTS: Cohen's Kappa coefficients were significant in 10 of the 28 computations (

CONCLUSION: Overall, our results indicated moderate to low interrater reliability, and raters never agreed that left asymmetry was present. While lower

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. …

The Prevalence And Spectrum Of Reported Incidental Adrenal Abnormalities In Abdominal Computed Tomography Of Cancer Patients: The Experience Of A Comprehensive Cancer Center, Aiham Qdaisat, Sara Bedrose, Obadah Ezzeldin, Ahmed W Moawad, Sai-Ching J Yeung, Khaled M Elsayes, Mouhammed Amir Habra

Faculty, Staff and Students Publications

BACKGROUND: The increasing use of computed tomography (CT) has identified many patients with incidental adrenal lesions. Further evaluation of these lesions is often dependent on the language used in the radiology report. Compared to the general population, patients with cancer have a higher risk for adrenal abnormalities, yet data on the prevalence and type of incidental adrenal lesions reported on radiologic reports in cancer patients is limited. In this study, we aimed to determine the prevalence and nature of adrenal abnormalities as an incidental finding reported on radiology reports of cancer patients evaluated for reasons other than suspected adrenal pathology. …