Nikolaos Papanikolaou

Dr. Nikolaos Papanikolaou

Champalimaud Foundation, Lisbon, Lisboa, Portugal
+3
orcid

Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

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

Representative Publications

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1 October 2021 in RadioGraphics
Verified
Journal Article
Open access
JSJoshua D. Shur
Joshua D. Shur
SDSimon Doran
Simon Doran
SKSantosh Kumar
Santosh Kumar
DDDerfel ap Dafydd
Derfel ap Dafydd
KDKate Downey
Kate Downey
MOMatthew R. Orton
Matthew R. Orton
Radiomics refers to the extraction of mineable data from medical imaging and has been applied within oncology to improve diagnosis, prognostication, and clinical decision support, with the goal of ... Radiomics refers to the extraction of mineable data from medical imaging and has been applied within oncology to improve diagnosis, prognostication, and clinical decision support, with the goal of ... Created with BioRender.com

17 January 2024 in Insights into Imaging
Verified
Journal Article
Open access
PDF file
BKBurak Kocak
Burak Kocak
TDTugba Akinci D'Antonoli
Tugba Akinci D'Antonoli
NMNathaniel Mercaldo
Nathaniel Mercaldo
AAAngel Alberich-Bayarri
Angel Alberich-Bayarri
BBBettina Baeßler
Bettina Baeßler
Renato CuocoloRenato Cuocolo
Renato Cuocolo
Purpose: To propose a new quality scoring tool, METhodological RadiomICs Score (METRICS), to assess and improve research quality of radiomics studies. Methods: We conducted an online modified Delphi study with a group of international experts. It was performed in three consecutive stages: Stage#1, item preparation; Stage#2, panel discussion among EuSoMII Auditing Group members to identify the items to be voted; and Stage#3, four rounds of the modified Delphi exercise by panelists to determine the items eligible for the METRICS and their weights. The consensus threshold was 75%. Based on the median ranks derived from expert panel opinion and their rank-sum based conversion to importance scores, the category and item weights were calculated. Result: In total, 59 panelists from 19 countries participated in selection and ranking of the items and categories. Final METRICS tool included 30 items within 9 categories. According to their weights, the categories were in descending order of importance: study design, imaging data, image processing and feature extraction, metrics and comparison, testing, feature processing, preparation for modeling, segmentation, and open science. A web application and a repository were developed to streamline the calculation of the METRICS score and to collect feedback from the radiomics community. Conclusion: In this work, we developed a scoring tool for assessing the methodological quality of the radiomics research, with a large international panel and a modified Delphi protocol. With its conditional format to cover methodological variations, it provides a well-constructed framework for the key methodological concepts to assess the quality of radiomic research papers. Critical relevance statement: A quality assessment tool, METhodological RadiomICs Score (METRICS), is made available by a large group of international domain experts, with transparent methodology, aiming at evaluating and improving research quality in radiomics and machine learning. Key points: • A methodological scoring tool, METRICS, was developed for assessing the quality of radiomics research, with a large international expert panel and a modified Delphi protocol. • The proposed scoring tool presents expert opinion-based importance weights of categories and items with a transparent methodology for the first time. • METRICS accounts for varying use cases, from handcrafted radiomics to entirely deep learning-based pipelines. • A web application has been developed to help with the calculation of the METRICS score (https://metricsscore.github.io/metrics/METRICS.html) and a repository created to collect feedback from the radiomics community (https://github.com/metricsscore/metrics). Graphical

27 October 2022 in Communications Medicine
Verified
Journal Article
Open access
PDF file
DKDow-Mu Koh
Dow-Mu Koh
Nikolaos PapanikolaouNikolaos Papanikolaou
Nikolaos Papanikolaou
UBUlrich Bick
Ulrich Bick
RIRowland Illing
Rowland Illing
CKCharles E. Kahn
Charles E. Kahn
FPFred Prior
Fred Prior
An increasing array of tools is being developed using artificial intelligence (AI) and machine learning (ML) for cancer imaging. The development of an optimal tool requires multidisciplinary engagement to ensure that the appropriate use case is met, as well as to undertake robust development and testing prior to its adoption into healthcare systems. This multidisciplinary review highlights key developments in the field. We discuss the challenges and opportunities of AI and ML in cancer imaging; considerations for the development of algorithms into tools that can be widely used and disseminated; and the development of the ecosystem needed to promote growth of AI and ML in cancer imaging.

10 November 2007 in European Radiology
Verified
Journal Article
Closed access
PDF file
SGSofia Gourtsoyianni
Sofia Gourtsoyianni
Nikolaos PapanikolaouNikolaos Papanikolaou
Nikolaos Papanikolaou
SYSpyros Yarmenitis
Spyros Yarmenitis
TMThomas Maris
Thomas Maris
AKApostolos Karantanas
Apostolos Karantanas
NGNicholas Gourtsoyiannis
Nicholas Gourtsoyiannis

1 May 2020 in Cancer Imaging
Verified
Journal Article
Open access
PDF file
Nikolaos PapanikolaouNikolaos Papanikolaou
Nikolaos Papanikolaou
CMCelso Matos
Celso Matos
DKDow Mu Koh
Dow Mu Koh
During the last decade, there is an increasing usage of quantitative methods in Radiology in an effort to reduce the diagnostic variability associated with a subjective manner of radiological interpretation. Combined approaches where visual assessment made by the radiologist is augmented by quantitative imaging biomarkers are gaining attention. Advances in machine learning resulted in the rise of radiomics that is a new methodology referring to the extraction of quantitative information from medical images. Radiomics are based on the development of computational models, referred to as “Radiomic Signatures”, trying to address either unmet clinical needs, mostly in the field of oncologic imaging, or to compare radiomics performance with that of radiologists. However, to explore this new technology, initial publications did not consider best practices in the field of machine learning resulting in publications with questionable clinical value. In this paper, our effort was concentrated on how to avoid methodological mistakes and consider critical issues in the workflow of the development of clinically meaningful radiomic signatures.

1 October 2001 in RadioGraphics
Verified
Journal Article
Closed access
PPPanos Prassopoulos
Panos Prassopoulos
Nikolaos PapanikolaouNikolaos Papanikolaou
Nikolaos Papanikolaou
JGJohn Grammatikakis
John Grammatikakis
MRMaria Rousomoustakaki
Maria Rousomoustakaki
TMThomas Maris
Thomas Maris
NGNicholas Gourtsoyiannis
Nicholas Gourtsoyiannis
Magnetic resonance (MR) enteroclysis imaging is emerging as a technique for evaluation of the small bowel in patients with Crohn disease. Administration of 1.5-2 L of isosmotic water solution through a nasojejunal catheter ensures distention of the bowel and facilitates identification of wall abnormalities. True fast imaging with steady-state precession (FISP), half-Fourier acquisition single-shot turbo spin-echo (HASTE), and postgadolinium T1-weighted three-dimensional fast low-angle shot sequences can be employed in a comprehensive and integrated MR enteroclysis examination protocol to overcome specific disadvantages of each of the sequences involved. Superficial abnormalities that are ideally delineated with conventional enteroclysis are not consistently depicted with MR enteroclysis. The characteristic transmural abnormalities of Crohn disease such as bowel wall thickening, linear ulcers, and cobblestoning are accurately shown with MR enteroclysis imaging, especially with the true FISP sequence. MR enteroclysis is comparable to conventional enteroclysis in the detection of the number and extent of involved small bowel segments and in the disclosure of luminal narrowing or prestenotic intestinal dilatation. The clinical utility of MR enteroclysis in Crohn disease has not been fully established. At present, the method may be used for follow-up studies of known disease, estimation of disease activity, and determination of the extramucosal extent and spread of the disease process.