Portable Supine OCT for Examination Under Anesthesia and Surgical Guidance

Abstract

Purpose: To evaluate portable supine OCT for examination under anesthesia of the retina of pediatric patients and guiding corneal surgery.

Methods: Two portable SD-OCT devices (ENVISU-C2300 and ENVISU-R4300, Bioptigen Inc, USA) with different hand-held probes were employed. ENVISU-C2300 provides near 3μm axial resolution and an imaging depth of 1.56 mm, in tissue. ENVISU-R4300 provides near 8μm axial resolution and an imaging depth of 5.6mm, in tissue. Two interchangeable imaging lenses can be separately mounted in the hand-held probe of both systems to image the retina or the cornea. The ENVISU-R4300 probe integrates a camera that provides real-time fundus display or en-face imaging of the eye. The two hand-held probes can be alternately secured to a modified OPMI stand (Aguilar MC et al, ARVO2011, E-abstract 4026) for imaging of patients in supine position. The OPMI was equipped with motorized adjustments to finely position the hand-held probe and image a designated area of the retina or the cornea. The ENVISU-C2300 corneal lens tube was modified to increase the free space distance from 40mm to 60mm and allow the surgeon to better access the surgical site during the imaging. The free space distance of the corneal imaging lens of the ENVISU-C4300 was 32mm and could not be increased.

Results: Twenty pediatric patients were imaged in the operating room and 3 DALK and 4 DSAEK surgeries were evaluated intraoperatively with the two SD-OCT configurations under an IRB approved protocol. The high axial resolution the C2300 system was preferred since it produced higher quality images of retina and cornea. The long imaging depth and the camera system of the R4300 engine facilitated alignment during ocular imaging and enabled OCT imaging of the cornea from white to white. The longer working distance of the C2300 facilitated surgeon operations during imaging.

Conclusions: Portable supine OCT with two different configurations was effective to perform retinal examination under anesthesia and guide corneal surgery. Support: DOD Grant DAMD-W81XWH-09-1-0675; NIH 2R44EY018021-02A1, 5R44EY019000-09, 5P30EY14801-8; Bioptigen Inc; Florida Lions Eye Bank; Research to Prevent Blindness; Henri and Flore Lesieur Foundation (JMP)

Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 688 retina • 741 transplantation