Room: Exhibit Hall
Purpose: External beam radiation therapy (EBRT) is currently accepted as the primary treatment modality for intraocular tumors. However, radiation-associated toxicities due to sophisticated ocular anatomy and shape variability of organs at risk (OAR) is a major concern. The purpose of this work is to develop a precise 3D eye modeling approach based on optical coherence tomography (OCT) technique for highly conformal dose distribution and thus to reduce the normal tissue complication probability.
Methods: An automatic algorithm including boundary segmentation, image registration, and optical correction was developed to segment the anterior segment from OCT images based on the graph theory and dynamic programming technique. Reconstructed anterior segment from OCT was then fused with segmented anterior segment from CT images to model a 3D full-eye. Final high precision registration was achieved by searching the best match between the OCT and CT images using a XOR operation. Standard schematic-eye and clinical patient datasets were used to validated and evaluated this automatic algorithm.
Results: The automatic segmentation of the anterior segment including cornea, iris, limbus and crystalline lens were acquired successfully. No significant differences were found between the automatic and manual measurements for all anterior segmentations. The average segmentation error and computational cost were approximately 0.2Â± 0.1 mm and 46Â±2 s (all the codes were written by MATLAB and run on a PC computer equipped with Intel Core processor i7-7500U 2.9GHz), respectively. Moreover, the proposed registration algorithm was able to correct the axial, sagittal and coronal displacements in the input images and revealed a mean registration error of 0.16 Â± 0.05â—¦ in 96 Â± 2 s for different angles.
Conclusion: This study demonstrated the 3D eye modeling approach based on OCT technique is accurate, reliability, and robustness, and may improve curative effect for intraocular tumors.