Recognition of Artifacts in MRIs

Large medical imaging datasets are becoming standard, but a crucial challenge remains: ensuring that every MRI scan is of sufficient quality, without artifacts that could compromise subsequent analyses or the diagnostic pathway.

Motivations & Objectives

  • Automate MRI image quality control, reducing manual work and subjective bias.
  • Overcome the scarcity of real artifact data through synthetic data augmentation, enabled by MRI physics-based simulators.
  • Provide fast, efficient, and reliable tools to support high-throughput clinical pipelines.

Methods

  • Artifact generators inspired by the physics of magnetic resonance imaging (MRI) to simulate errors, distortions, and noise on brain images.
  • Extraction of abstract and engineered features, able to compactly describe images and facilitate artifact classification.
  • Automatic feature selection specific to each type of artifact, achieving maximum discriminative power for multisite/multiscanner detection.
  • Robust SVM classifiers, trained on selected features, to automatically identify nine types of MRI artifacts.

Novelty & Contributions

  • Physical artifact generators to greatly expand datasets, making manual collection of rare cases less essential.
  • Definition and validation of a large pool of features for the detection of nine classes of artifacts in structural MRI.
  • Feature selection module specific for artifact—“class by class” optimization.

Results & Validation

  • Performance evaluated on mixed databases (synthetic artifacts and clinical trial on multiple sclerosis with expert labels): up to +12.5 percentage points increase in accuracy, F1, F2, precision, and recall compared to conventional methods.
  • Computationally light pipeline: <1 second per scan, ideal for real-time implementation in clinical departments and large biobanks.


Related Scientific Articles

  • An efficient semi-supervised quality control system trained using physics-based MRI-artefact generators and adversarial training
    (arXiv preprint arXiv:2206.03359, 2022)
    PubMed

    Authors: Daniele Ravi, Frederik Barkhof, Daniel C. Alexander, Lemuel Puglisi, Geoffrey JM Parker, Arman Eshaghi (for ADNI)


Code Repository

  • Automatic Quality Control (artifact generator, SVM, feature selection):
    daniravi/automatic-quality-control

    Main components: src/qcs/artefacts/ (artifact generators), src/qcs/feature_extraction.py (features), src/qcs/feature_selection.py


Team & Authors

  • Daniele Ravì (PI, artifact simulator and SVM pipeline development)
  • Lemuel Puglisi (Feature engineering, QSA code contributions)
  • Frederik Barkhof, Daniel C. Alexander, Geoffrey JM Parker, Arman Eshaghi
Published
Categorised as NEWS eng