Anterior segment SD-OCT is a powerful new technology that is able to acquire volumetric data that can be rendered and manipulated three-dimensionally and provides increased utility compared to the cross-sectional data gathered from commercially available anterior segment time domain OCT instruments. Individual slices from the three-dimensional anterior segment SD-OCT dataset consist of individual B-scans that contain the postoperative clear corneal incision. The three-dimensional architecture of the wound and specific features of the wound, such as areas of stromal edema, could be determined by software analysis of the wound on each consecutive B-scan. Volumetric data have a distinct advantage over a single time domain B-scan in that the full three-dimensional architecture of a clear corneal incision can be rendered.
Anterior segment SD-OCT of the cornea has been described previously using an 830-nm device.8
The longer wavelength of 1,310-nm SD-OCT is advantageous because it allows for deeper tissue penetration. Thus, full-thickness cornea, sclera, and iris can be imaged, providing a full assessment of anterior segment anatomy and pathology. This article serves as a proof of concept that 1,310-nm anterior segment SD-OCT can obtain volumetric data of a clear corneal incision. Currently, the axial resolution of the device is 8 µm and the instrument has a 7-second three-dimensional acquisition time and consequently is subject to motion artifact. However, inevitable improvements in the light source and acquisition speed will improve axial resolution and minimize motion artifact.
We have demonstrated an anterior segment SD-OCT system that can acquire three-dimensional data of the anterior segment and can be used to assess clear corneal incisions. Ultimately, this technology will allow consecutive B-scans to be segmented to reveal the three-dimensional architecture of clear corneal incisions, thus providing an anatomic characterization of the optimal surgical wound.