Kiki Theodorou

Dr. Kiki Theodorou

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 April 2014 in Cancer Imaging
Verified
Journal Article
Open access
PSPatricia Svolos
Patricia Svolos
EKEvanthia Kousi
Evanthia Kousi
KEKapsalaki Fountas Eftychia
Kapsalaki Fountas Eftychia
Kiki TheodorouKiki Theodorou
Kiki Theodorou
IFIoannis Fezoulidis
Ioannis Fezoulidis
Ioannis M. TsougosIoannis M. Tsougos
Ioannis M. Tsougos
The role of conventional Magnetic Resonance Imaging (MRI) in the detection of cerebral tumors has been well established. However its excellent soft tissue visualization and variety of imaging sequences are in many cases non-specific for the assessment of brain tumor grading. Hence, advanced MRI techniques, like Diffusion-Weighted Imaging (DWI), Diffusion Tensor Imaging (DTI) and Dynamic-Susceptibility Contrast Imaging (DSCI), which are based on different contrast principles, have been used in the clinical routine to improve diagnostic accuracy. The variety of quantitative information derived from these techniques provides significant structural and functional information in a cellular level, highlighting aspects of the underlying brain pathophysiology. The present work, reviews physical principles and recent results obtained using DWI/DTI and DSCI, in tumor characterization and grading of the most common cerebral neoplasms, and discusses how the available MR quantitative data can be utilized through advanced methods of analysis, in order to optimize clinical decision making.

28 June 2024 in Medicine
Verified
Journal Article
Open access
FSFoteini Simopoulou
Foteini Simopoulou
GKGeorge Kyrgias
George Kyrgias
IGIoannis Georgakopoulos
Ioannis Georgakopoulos
RARaphaela Avgousti
Raphaela Avgousti
CAChristina Armpilia
Christina Armpilia
AZAnna Zygogianni
Anna Zygogianni
Purpose: The current review aims to summarize the international experience of the impact of adaptive radiotherapy on dosimetry and clinical and toxicity outcomes. Additionally, it might trigger Radiation Oncologists to use ART and evaluate whether ART improves target volume coverage and/or normal tissue sparing and, consequently, therapeutic results. Materials and methods: We conducted an electronic literature search of PubMed/MEDLINE and ScienceDirect from January 2007 to January 2023. The search adhered to the PRISMA guidelines and employed keywords such as ART, HNC, parotid gland, and target volume. Furthermore, we examined the reference lists for studies pertinent to the present review. This study included both retrospective and prospective studies that were considered for inclusion. Conclusion: ART replanning appears to be a sustainable strategy to minimize toxicity by improving normal tissue sparing. Furthermore, it can enhance target volume coverage by correctly determining the specific dose to be delivered to the tumor. In conclusion, this review confirmed that ART benefits dosimetric, clinical/therapeutic, and toxicity outcomes.

21 November 2023 in Applied Sciences
Verified
Journal Article
Open access
PDF file
AGAngeliki Gkikoudi
Angeliki Gkikoudi
SKSPYRIDON ALEXANDER KALOSPYROS
SPYRIDON ALEXANDER KALOSPYROS
STSotiria Triantopoulou
Sotiria Triantopoulou
SLStella Logotheti
Stella Logotheti
VSVasiliki Softa
Vasiliki Softa
ALEXANDROS GEORGAKILASALEXANDROS GEORGAKILAS
ALEXANDROS GEORGAKILAS
Radiotherapy (RT) is a major part of cancer treatment. The reported variability in patient response to this modality can interfere with the continuation of best-possible care, promote side effects, and lead to long-term morbidity. Tools to predict a patient’s response to radiation could be highly useful in improving therapeutic outcomes while minimizing unnecessary and toxic exposure to radiation. This study investigates the potential of using molecular biomarkers as predictors of radiosensitivity in clinical practice. We review relative studies researching the positive correlation between various molecular biomarkers and patient radiosensitivity, including DNA damage response and repair proteins, inflammation and apoptosis markers, cell cycle regulators, and other biological markers. The clinical perspectives and applicability of these biomarkers in the prediction of radiosensitivity are also critically discussed. Conclusively, we underline the dynamics of molecular biomarkers to improve the efficacy and safety of radiotherapy in clinical practice and highlight the need for further research in this field. Identification of the most prominent markers is crucial for the personalization of therapies entailing ionizing radiation.

1 November 2015 in Physica Medica
Verified
Journal Article
Closed access
GGG. Gourzoulidis
G. Gourzoulidis
EKEfthymios Karabetsos
Efthymios Karabetsos
ΝSΝ. Skamnakis
Ν. Skamnakis
AXA. Xrtistodoulou
A. Xrtistodoulou
Constantin KappasConstantin Kappas
Constantin Kappas
TMT.G. Maris
T.G. Maris

6 July 2023 in Automation
Verified
Journal Article
Open access
PDF file
SRSotiris Raptis
Sotiris Raptis
VSVasiliki Softa
Vasiliki Softa
Georgios AngelidisGeorgios Angelidis
Georgios Angelidis
CIChristos Ilioudis
Christos Ilioudis
Kiki TheodorouKiki Theodorou
Kiki Theodorou
Radiomics has shown great promise in predicting various diseases. Researchers have previously attempted to include radiomics in their automated detection, diagnosis, and segmentation algorithms, taking these steps based on the promising outcomes of radiomics-based studies. As a result of the increased attention given to this topic, numerous institutions have developed their own radiomics software. These packages, on the other hand, have been utilized interchangeably without regard for their fundamental differences. The primary purpose of this study was to explore benefits of predictive model performance for radiation pneumonitis (RP), which is the most frequent side effect of chest radiotherapy, and through this work, we developed a radiomics model based on deep learning that intends to increase RP prediction performance by combining more data points and digging deeper into these data. In order to evaluate the most popular machine learning models, radiographic characteristics were used, and we recorded the most important of them. The high dimensionality of radiomic datasets is a major issue. The method proposed for use in data problems is the synthetic minority oversampling technique, which we used in order to create a balanced dataset by leveraging suitable hardware and open-source software. The present study assessed the efficacy of various machine learning models, including logistic regression (LR), support vector machine (SVM), random forest (RF), and deep neural network (DNN), in predicting radiation pneumonitis by utilizing specific radiomics features. The findings of the study indicate that the four models displayed satisfactory efficacy in forecasting radiation pneumonitis. The DNN model demonstrated the highest area under the receiver operating curve (AUC-ROC) value, which was 0.87, suggesting its superior predictive capacity among the models considered. The AUC-ROC values for the random forest, SVM, and logistic regression models were 0.85, 0.83, and 0.81, respectively.

18 December 2024 in BioMedInformatics
Verified
Journal Article
Open access
PDF file
SRSotiris Raptis
Sotiris Raptis
CIChristos Ilioudis
Christos Ilioudis
Kiki TheodorouKiki Theodorou
Kiki Theodorou
Background: Lung cancer still maintains the leading position among causes of death in the world; the process of early detection surely contributes to changes in the survival of patients. Standard diagnostic methods are grossly insensitive, especially in the early stages. In this paper, radiomic features are discussed that can assure improved diagnostic accuracy through automated lung cancer detection by considering the important feature categories, such as texture, shape, and intensity, originating from the CT DICOM images. Methods: We developed and compared the performance of two machine learning models—DenseNet-201 CNN and XGBoost—trained on radiomic features with the ability to identify malignant tumors from benign ones. Feature importance was analyzed using SHAP and techniques of permutation importance that enhance both the global and case-specific interpretability of the models. Results: A few features that reflect tumor heterogeneity and morphology include GLCM Entropy, shape compactness, and surface-area-to-volume ratio. These performed excellently in diagnosis, with DenseNet-201 producing an accuracy of 92.4% and XGBoost at 89.7%. The analysis of feature interpretability ascertains its potential in early detection and boosting diagnostic confidence. Conclusions: The current work identifies the most important radiomic features and quantifies their diagnostic significance through a properly conducted feature selection process reflecting stability analysis. This provides the blueprint for feature-driven model interpretability in clinical applications. Radiomics features have great value in the automated diagnosis of lung cancer, especially when combined with machine learning models. This might improve early detection and open personalized diagnostic strategies for precision oncology.