A new, high resolution, real-time, ocular imaging system for femtosecond cataract surgery

1. Harvey Uy¹
2. Gary Gray²
3. Randy Frey²
4. Steve Bott²
5. Pik Sha Chan¹

¹Asian Eye Institute, Makati City, the Philippines
²LensAR Inc, Orlando, Florida, USA

Purpose: To develop an imaging system capable of providing high resolution, real-time, images of ocular structures over a wide depth of field that would enable accurate placement of femtosecond lasers for cataract surgery.

Methods: A rotating camera and a scanning laser source were combined to produce a system called 3-Dimensional Confocal Structured Illumination (3D-CSI). The 3D-CSI system was applied to animal, cadaver and patient eyes and used to acquire high resolution images of key ocular surfaces (anterior and posterior cornea and lens capsules), with high signal-to-noise and contrast-to-noise ratios. Computerized ray-tracing software were used to determine whether these images could generate 3D models of ocular structures that could guide computerized application of femtosecond laser energy to the anterior lens capsule and nucleus.

Results: The 3D-CSI system successfully acquired high resolution images in all animal, cadaver and live human eyes. The automated software successfully used these images to create 3D models of the anterior segments that were used to guide femtosecond laser treatment to the anterior lens capsule and nucleus. Automated software removed the risk of operator error while providing over-ride for the operator prior to treatment. Key ocular surfaces were automatically identified and the laser patterns delivered without errors in placement.

Conclusions: The 3D-CS system provides ocular images with enhanced contrast and resolution without the need for image stitching. Sufficient detail was present to allow automated laser application into key ocular structures for femtosecond cataract surgery.