Methods and apparatus for reducing artifacts in OCT angiography using machine learning techniques
In some embodiments of the present invention, a method of reducing artifacts includes obtaining OCT/OCTA data from an OCT/OCTA imager; preprocessing OCTA/OCT volume data; extracting features from the preprocessed OCTA/OCT volume data; classifying the OCTA/OCT volume data to provide a probability determination data; determining a percentage data from the probability data determination; and reducing artifacts in response to the percentage data.
1. A method of reducing artifacts, comprising:
obtaining OCT/OCTA data from an OCT/OCTA imager;
preprocessing OCTA/OCT volume data;
extracting features from the preprocessed OCTA/OCT volume data;
classifying the OCTA/OCT volume data to provide a probability determination data, wherein classifying the OCTA/OCT data includes returning a probability determination data that represents the probability in each base unit that the base unit belongs to one of a set of classification categories;
determining a percentage data from the probability determination data; and
reducing artifacts in response to the percentage data.
2. The method of claim 1 , wherein extracting features includes extracting features in each base unit of the OCTA/OCT data.
3. The method of claim 2 , wherein the base unit can be a single voxel.
4. The method of claim 2 , wherein the base unit is a plurality of voxels.
5. The method of claim 1 , wherein the set of classification categories includes a purely true flow signal, a purely artifact signal, or a mixture of both true flow and artifact signals.
6. The method of claim 1 , wherein classifying the OCTA/OCT data includes using a trained classifier to determine the probability determination data.
7. The method of claim 6 , further including training the trained classifier, training the trained classifier comprising:
providing a training dataset;
preprocessing the training dataset;
extracting features in the training dataset;
classifying the training dataset to obtain probability determination data;
comparing the probability determination data with human labeled probability data;
refining the trained classifier such that the probability determination data matches the human labeled probability data.
8. A method of reducing artifacts, comprising:
obtaining OCT/OCTA data from an OCT/OCTA imager;
preprocessing OCTA/OCT volume data;
extracting features from the preprocessed OCTA/OCT volume data;
classifying the OCTA/OCT volume data to provide a probability determination data;
determining a percentage data from the probability determination data; and
reducing artifacts in response to the percentage data,
wherein preprocessing OCTA/OCT volume data, comprises:
detection of regions with the OCTA/OCT signals above background noise,
excluding regions in the OCTA/OCT signals that are not above background noise,
detecting landmarks along each OCTA/OCT A-line, and
flattening to align all of A-scans with a chosen landmark.
9. A method of reducing artifacts, comprising:
obtaining OCT/OCTA data from an OCT/OCTA imager;
preprocessing OCTA/OCT volume data;
extracting features from the preprocessed OCTA/OCT volume data;
classifying the OCTA/OCT volume data to provide a probability determination data;
determining a percentage data from the probability determination data; and
reducing artifacts in response to the percentage data,
wherein determining a percentage data from the probability determination data includes a transform equation or matrix to transform the probability of the base unit belonging to each categories to a single true flow signal percentage value in the base unit.