Purpose
Hand-held, scope-mounted optical coherence tomographic (OCT) instruments are being used to obtain intraocular images of retinal tissues. We have developed a 23-gauge side-imaging endoscopic OCT probe with the cooperation of NIDEK Co., Ltd and NU SYSTEM, Inc., and have obtained intraoperative images of ocular tissues from inside the globe of cadaver pig eyes and white rabbit eyes.
Methods
This fiber-type OCT consists of a swept-source OCT (SS-OCT) with a swept source laser (central wavelength of 1060 nm, super luminous diode (SLD) with a spectral width of 100 nm and scanning rate of 100 kHz). The probe is a side-imaging type, and the light is projected from the tip of the probe at an oblique angle to the interior of the eye. Vitrectomy using a 23-gauge trocar was performed on animal eyes, and the objective light was projected for 1.5 mm distance to the objects. Images were obtained from different parts of the ocular tissue.
Results
In pig eyes, detailed images were successfully obtained of different sites, such as iatrogenic micro retinal tears, retinal detachments, a curled-up internal limiting membrane, and the corrugated structure of the pars plicata. In rabbit eyes, detailed images of the retina, optic disc, retinal vessels, iatrogenic retinal tears, and retinal detachments were obtained. Real-time OCT images could be observed in a small monitor attached at the lens-barrel so that the surgeon could manipulate the OCT probe without averting his eyes too much.
Conclusions
Fiber optic type of OCT probe can be used to obtain detailed images of the structure of ocular tissues which can provide sufficient information on the course of intraoperative surgical procedures.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
688 retina •
419 anatomy