OCT Image Brightness Correction for Fixation Displacement Artifacts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In OCT angiography, fixation displacement during multiple scans of the same site of the fundus leads to artifacts that are difficult to remove, affecting the reliability of analysis results by confusing blood vessel regions with artifact regions.
Innovation Solution
An ophthalmic image processing apparatus with a storage unit, a first brightness profile generation unit, a second brightness profile generation unit, and a brightness correction unit, which integrates and processes brightness values to correct image data, reducing artifacts by generating a second brightness profile through smoothing filters and applying brightness correction based on the ratio or difference between the first and second profiles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple scans are performed to obtain OCT angiography images, then blood vessel information is enhanced, but fixation displacement causes artifacts that reduce image quality
Solution Approach 1:
The patent applies preliminary action by generating brightness profiles from multiple scans before performing the final image synthesis. The brightness profiles are calculated in advance and stored, then used during image synthesis to compensate for fixation displacement artifacts, thereby improving blood vessel analysis reliability while eliminating the harmful effects of displacement
Solution Approach 2:
The patent introduces brightness profiles as an intermediary element between the raw scan data and the final OCT angiography image. These brightness profiles serve as a mediator that captures fixation displacement information and enables artifact correction during image synthesis, resolving the contradiction between enhancing blood vessel information and eliminating displacement artifacts
2Object-affected harmful factors
If tracking control is applied to move the OCT optical system, then fixation displacement is compensated, but artifact regions are still emphasized in the image
Solution Approach 1:
The patent applies parameter changes by modifying the brightness distribution parameters through brightness profile integration and correction. Instead of relying solely on positional tracking, the system changes the brightness parameters to compensate for fixation displacement, thereby reducing emphasized artifact regions while maintaining displacement compensation
3Object-affected harmful factors
If brightness correction is performed using brightness profiles, then artifacts are reduced, but processing complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the image processing into distinct stages: brightness profile generation from individual scans, brightness profile integration across multiple scans, and final image synthesis with artifact correction. This segmented approach reduces artifacts while managing processing complexity by organizing operations into modular, manageable steps
Data Source
AI summary
An ophthalmic image processing apparatus of an embodiment includes a storage unit, a first brightness profile generation unit, a second brightness profile generation unit, and a brightness correction unit. The storage unit is configured to store image data acquired through scanning a subject's eye using optical coherence tomography. The first brightness profile generation unit is configured to generate a first brightness profile along a first direction by integrating brightness values of the image data. The second brightness profile generation unit is configured to process the first brightness profile to generate a second brightness profile. The brightness correction unit is configured to perform brightness correction of the image data based on the first brightness profile and the second brightness profile.