advertisement
Geerling et al. (167) describe a new technology that is a step towards intraoperative high resolution anterior segment ocular imaging. The authors use a 1310 nm wavelength to enhance anterior segment imaging, and perform cross-sectional optical imaging at the time of surgical procedures. The authors suggest that such technology may be useful in trabeculectomy and lamellar keratoplasty. Further refinements, they speculate, might make enable the use of this technology for intraoperative pachymetry, vitreoretinal and macular surgery. The technology described is slower (100 A-scans/second) and has lower resolution (15 microns) than commercially available OCT, but is coupled to an operating microscope. The unit used by the authors is clearly a proof-of-principle device. The device has no aiming beam and requires a separate operator to capture data. Focus is critical, as the imaging window is only two mm in the z-direction. Because acquisition is slow and not surgeon controlled, the operation must be halted for scanning. It is possible, however, to see structures in vivo, such as the anterior chamber angle, that are not otherwise visible with OCT. Geerling et al. have demonstrated the feasibility of intraoperative OCT. Improvements in this technology, including improved acquisition speed, such as is possible with spectral OCT, true integration into the operating microscope, heads-up display and surgeon control, may make this a clinically useful device. In addition, the appropriate wavelengths must be chosen, requiring precise optics for each, for anterior and posterior segment work. With these refinements, optical biopsy with OCT may prove to enable and direct surgical biopsy and excision in the future.