Abstract
Purpose :
We demonstrate the evolution of bedside, swept source, handheld optical coherence tomography (HH-OCT) and OCT angiography (OCTA) imaging with increasing scanning speeds for patients at risk for retinal ischemic events in infant and adult intensive care units (ICU).
Methods :
We developed an investigational swept source OCT system at 100 kHz and increased scanning speed to 200 and 400 kHz to shorten the time of structural OCT capture and acquire OCTA. The handheld probe was lightweight and optimized for supine imaging. The increase in OCT speed required a heavier probe and was redesigned to fit comfortably and optimize balance in the operator’s hand (Fig 1). We tested an ergonomic chair for stabilization body and forearm during imaging.
Results :
At 100 kHz, we acquired OCT volumes without pharmacological pupil dilation in infants in the ICU. At 200 kHz, we readily obtained non-dilated OCT volumes in infants with congenital cardiac diseases and in adults before, during and after cardiac surgery. The 200 kHz OCTA capture was poor without pupil dilation, and was limited by pupil size and cardiac surgical motion. At 400 kHz, stabilization of the imager by an ergonomic chair decreased imager fatigue and imager-related motion artifacts. The decrease in OCTA scan acquisition time from 6 sec (at 200 kHz) to 3.6 sec (at 400 kHz) decreased motion artifacts and allowed for a stronger OCTA signal despite lack of pupil dilation.
Conclusions :
The evolution of the handpiece, capture speed and ergonomic support, allowed capture of high quality structural OCT as well as OCTA with minimal artifacts. We are applying these advances to improve our understanding of the pathophysiology of retinal vascular events in cardiac patients.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.