Interobserver Variability in Target Definition for Stereotactic Arrhythmia Radioablation
Abstract
ABSTRACT Background Stereotactic arrhythmia radioablation (STAR) is emerging as a potential new therapy for patients with refractory ventricular tachycardia (VT). The arrhythmogenic substrate (target) is synthesized from clinical and electro-anatomical information. This study was designed to evaluate the baseline interobserver variability in target delineation for STAR. Methods Delineation software designed for research purposes was used. The study was split into three phases. Firstly, electrophysiologists (observers) delineated a well-defined structure in three patients (spinal canal). Secondly, observers delineated the arrhythmogenic cardiac VT target in three patients previously treated with STAR based on case descriptions. To evaluate baseline performance, a basic workflow approach was used, no advanced techniques were allowed (e.g. image integration). Thirdly, observers delineated three predefined segments from the cardiac 17-segment model. Interobserver variability was evaluated by assessing volumes, variation in distance to the median volume as expressed by the root-mean-square of the observer standard deviation (RMS SD) over the target volume, and the Dice coefficient. Results Ten electrophysiologists completed the study. For the first phase (spinal canal delineation), interobserver variability was low as indicated by low variation in distance to the median volume (RMS SD range: 0.02-0.02cm) and high Dice coefficients (mean: 0.97±0.01). In the second phase (VT-target delineation), distance to the median volume was large (RMS SD range: 0.52-1.02cm) and the Dice coefficients low (mean: 0.40±0.15). In the third phase (segment delineation), similar results were observed (RMS SD range: 0.51-1.55cm, Dice coefficient mean: 0.31±0.21) Conclusions Interobserver variability is high for manual delineation of the VT-target and ventricular segments. Difficulties in cardiac anatomical orientation on traditional radiation oncology CT scans appear to be an important driver of variability. This evaluation of the baseline observer variation shows that there is a need for methods and tools to improve variability and allows for future comparison of interventions aiming to reduce observer variation.
Authors 19
-
Amsterdam UMC Location University of Amsterdam · Amsterdam Cardiovascular Sciences
Affiliation as printed
Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands
-
Washington University in St. Louis
Affiliation as printed
Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, Missouri, USA
-
Manchester Academic Health Science Centre · University of Manchester
Affiliation as printed
Department of Radiation Oncology, University of Manchester, Manchester Academic Health Centre, Manchester, UK
-
Washington University in St. Louis
Affiliation as printed
Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri, USA
-
Affiliation as printed
Department of Cardiology, St. Antonius Hospital, Nieuwegein, the Netherlands
-
South Tees Hospitals NHS Foundation Trust
Affiliation as printed
Department of Cardiology, South Tees Hospitals NHS Foundation Trust, Middleborough, UK
-
University of California San Diego
Affiliation as printed
Department of Medicine, Division of Cardiology Cardiac Electrophysiology, Cardiovascular Institute, University of California San Diego, San Diego, California, USA
-
Centre Hospitalier Universitaire Vaudois · University of Lausanne
Affiliation as printed
Heart and Vessel Department, Service of Cardiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
-
Centre Hospitalier Universitaire Vaudois · University of Lausanne
Affiliation as printed
Heart and Vessel Department, Service of Cardiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
-
Amsterdam UMC Location University of Amsterdam · Amsterdam Cardiovascular Sciences
Affiliation as printed
Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands
-
Affiliation as printed
Department of Immunity, Infection and Cardiovascular Disease, University of Sheffield Sheffield, UK
-
Affiliation as printed
Section of Cardiac Electrophysiology, Emory University, Atlanta, Georgia, USA
-
Washington University in St. Louis
Affiliation as printed
Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, Missouri, USA
-
Centre Hospitalier Universitaire de Bordeaux · Electrophysiology and Heart Modeling Institute
Affiliation as printed
Cardiac arrhythmia department, IHU LIRYC, Bordeaux University Hospital, Bordeaux, France
-
Centre Hospitalier Universitaire de Bordeaux · Electrophysiology and Heart Modeling Institute
Affiliation as printed
Cardiac arrhythmia department, IHU LIRYC, Bordeaux University Hospital, Bordeaux, France
-
Amsterdam University Medical Centers
Affiliation as printed
Department of Radiation Oncology, Amsterdam UMC, Amsterdam, the Netherlands
-
Washington University in St. Louis
Affiliation as printed
Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri, USA
-
Leiden University Medical Center
Affiliation as printed
Department of Radiation Oncology, LUMC, Leiden, the Netherlands
-
Pieter G. Postema corresponding
Amsterdam UMC Location University of Amsterdam · Amsterdam Cardiovascular Sciences
Affiliation as printed
Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands
Cited by 0 stored of 0
No patents citing this paper on Lens.org (checked 2026-10-11).