A comparison between detectors of high frequency oscillations
1Montreal Neurological Institute and Hospital, McGill University, Montreal, Québec, Canada. rina.zelmann@mail.mcgill.ca
Summary
Automatic detection of high-frequency oscillations (HFOs) is essential for identifying epileptogenicity. Our novel detector demonstrated superior sensitivity and fewer false positives compared to existing methods on a standardized dataset.
Area of Science:
- Neuroscience
- Biomedical Engineering
Background:
- High-frequency oscillations (HFOs) are critical biomarkers for detecting epileptogenic tissue.
- Manual identification of HFOs is labor-intensive and subjective, necessitating automated solutions.
Purpose of the Study:
- To compare the performance of four automated HFO detection algorithms on a unified dataset.
- To introduce and evaluate a novel HFO detector with an improved feature for handling channels lacking a discernible baseline.
Main Methods:
- Intracerebral EEGs from 20 patients were analyzed, with HFOs and baselines identified by expert reviewers.
- Four existing HFO detectors and a newly developed detector were implemented and configured for optimal performance.
- Performance was assessed using receiver operating characteristic curves, false discovery rates, and channel-level rankings.
Main Results:
- All evaluated HFO detectors showed improved performance when utilizing an optimized configuration.
- The novel detector exhibited higher sensitivity and lower false positive rates compared to other methods, with comparable false detection rates.
- Performance differences were most pronounced in channels with high HFO activity.
Conclusions:
- The developed detector outperformed existing methods on the tested dataset, particularly in challenging channels.
- Optimizing detector configurations for specific data types significantly enhances performance.
- Standardized dataset comparisons are vital for evaluating HFO detection algorithms and understanding validation challenges.
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