Microscope-mounted OCT showed anterior segment structures intraoperatively

An optical coherence tomographer mounted on an operating microscope may be a helpful tool for imaging the anterior segment intraoperatively, according to German researchers. Lamellar dissection techniques, such as deep anterior lamellar keratoplasty and trabeculectomy, may particularly be aided by this type of modified OCT, the researchers said.

Gerd Geerling, MD, and colleagues performed several surgical cases using a 1310-nm optical coherence tomographer coupled to an operating microscope (OP-OCT) to determine the feasibility of its use during anterior segment surgery. The OP-OCT was used in three patients undergoing lamellar keratoplasty and one patient undergoing trabeculectomy.

The OP-OCT image was displayed on a screen next to a screen showing the direct microscope view. Both normal and pathologic anterior segment structures were detected with the OP-OCT, the researchers said.

During deep lamellar keratoplasty, “the OP-OCT was able to show corneal abnormalities and the lamellar interface,” the researchers said. They noted, however, that “the metal instruments used for lamellar dissection of the tissue created reflection and absorption of the laser light, so underlying structures were not visible with the OP-OCT intraoperatively.”

The researchers acknowledged that the current modification requires “a number of technical improvements to justify its use in routine surgery.”

The researchers’ new instrument report is published in the February issue of Archives of Ophthalmology.