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Four-Dimensional Computed Tomography (4DCT) in Radiation Oncology: A Practical Overview

  • Computed Tomography (Savvas Nicolaou and Mohammed F. Mohammed, Section Editors)
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Abstract

Purpose of Review

It has been 20 years since four-dimensional computed tomography (4DCT) was adopted in radiation oncology. By acquiring respiratory-correlated CT images, 4DCT allows characterization of tumour motion during radiotherapy target delineation. This technology has improved tumour delineation accuracy, in fact, it is now considered essential for highly conformal, high radiation, and precise radiotherapy treatment delivery. Nevertheless, due to the sampling of irregular patient breathing cycles, 4DCT suffers from image artefacts that can compromise tumour delineation accuracy. Addressing this challenge has been the driving motivation behind the latest advancements in 4DCT implementations. The purpose of this review is to provide a practical overview on 4DCT technology, its developments, and how it is used in radiation oncology.

Recent Findings

The most significant hardware advancement in helical CT scanner technology has been the increase of CT-slices from 16 to 256/320-slice, allowing faster scan times. In terms of software developments, reconstruction algorithms have greatly improved, and a multitude of artefact reduction techniques has been demonstrated to be beneficial—though not all are commercially available. Nowadays, it is possible to significantly reduce artefacts to nearly non-discernible levels. This is achievable through recent innovations in 4DCT which merge advanced hardware and software tools to implement patient-specific models that account for breathing irregularities to efficiently acquire high-integrity CT data.

Summary

This article provides a practical review of how 4DCT technology has evolved in radiation oncology, from both a technical and logistical point of view.

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Data Availability

No datasets were generated or analysed during the current study.

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Acknowledgements

The author would like to thank Dr. Kelly Paradis for her helpful discussions while planning this review article.

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Authors and Affiliations

  1. Department of Radiation Oncology, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia

    Ghada Aldosary

  2. King Abdullah International Medical Research Center, Riyadh, Saudi Arabia

    Ghada Aldosary

  3. Princess Nora bint Abdul Rahman University, Riyadh, Saudi Arabia

    Ghada Aldosary

  4. The Ottawa Hospital Research Institute, Ottawa, ON, Canada

    Ghada Aldosary

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Aldosary, G. Four-Dimensional Computed Tomography (4DCT) in Radiation Oncology: A Practical Overview. Curr Radiol Rep (2024). https://doi.org/10.1007/s40134-024-00427-6

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