Abstract
Purpose :
To compare in pediatric use the ability of a handheld versus a mounted flexible arm spectral domain optical coherence tomography (SD-OCT) device to evaluate the retina and choroid at the posterior pole. Analyzing B-Scans, we focused comparisons on the robust identification of individual retinal layers (RL) and on the definition of individual pathologies. We also assessed the instruments’ ease of use.
Methods :
We compared the clinical imaging results of the Envisu C2300 (Leica Microsystems, Germany) with the Spectralis & FLEX Module (Heidelberg Eng., Germany) in a routine clinical setting in unanaesthetized patients. The patients (N=40; mean age 15 m; SD 23.7 m; range 4 w to 5 y) had both eyes imaged with both OCT systems. Typical clinical indications were nystagmus of different origin, prematurity, and chorioretinal coloboma. Raw data were exported to a customized RL analysis software (DiOCTA, Giessen, Germany).
Results :
In both sets of images structural irregularities of RLs were identifiable, and individual RL segmentation was possible, however variability was lower with FLEX data. The Envisu device does not use eye-tracking but calculates an average of the posterior pole based on the B-Scans. The eye-tracking system of the FLEX device is impractical in awake infants and todllers due to rapid eye movement leading to a decoupled display of the infrared overview and OCT-scan position. Scan acquisition time was significantly shorter for the FLEX device due to its higher scan rate (A-Scans/sec). The Envisu device was easier to handle in various patient positions (e.g. in a baby stroller, on mothers arm).
Conclusions :
Both SD-OCT systems were useful to visualize with high resolution retinal morphology at the posterior pole and allowed for rapid image acquisition. However the FLEX device was faster and yielded better image quality. The real time infrared fundus imaging with the FLEX device made finding the region of interest faster, making handling easier for clinicians. In contrast, the Envisu device allows more comfortable positioning of patients and a more precise correspondence of the OCT B-Scan to the retinal area indicated on the calculated fundus image. Both devices allow efficient screening, early diagnosis, and quantitative longitudinal monitoring of retinal morphology in awake infants and toddlers.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.