Abstract
Purpose :
To optimise the protocol for hand-held optical coherence tomography (HH-OCT), and to investigate, for the first time, reliability of 3-dimensional full circumpapillary retinal nerve fibre layer (cpRNFL) analysis in children, with and without glaucoma, without the use of sedation.
Methods :
Ten children with pediatric glaucoma (n=17 affected eyes; range 0.8-14.7 years of age) and 10 adults with primary open angle glaucoma (n=20 affected eyes; range 55.4-75.5 years) were recruited along with 10 healthy children and 10 healthy adults. All participants underwent OCT imaging using a hand-held device. Test-retest repeatability and inter-assessor reproducibility was investigated for the pediatric cohort. Inter-device validity was assessed by comparing hand-held OCT scans to table-mounted OCT scans, in adults. Measures of reliability are described using intra-class correlation coefficients (ICCs), bias and coefficient of variation (CoV). cpRNFL thickness was assessed along several visual angles from the optic nerve center: three circular rings at 3, 4 and 5° radii; and two annuli between 4-5° and 5-6°, across all 4 quadrants.
Results :
The feasibility of obtaining a single scan with a full surrounding cpRNFL in children and adults, was 85% and 88%, respectively. Validity analysis showed poor reliability at 4° especially in the temporal quadrant, however high ICC values at 6° were achieved across all quadrants. ICCs for test-retest repeatability ranged from 0.56-0.74 at 4°, with the nasal and temporal quadrants showing the worst results, which improved at 6° to 0.79-0.83. Reproducibility at 4° was fairly high, however a large bias of 13.00μm presented in the nasal quadrant. ICCs for reproducibility at 6° were > 0.97 across all quadrants.
Conclusions :
We demonstrated excellent feasibility and reliability of cpRNFL thickness values for the first time without the use of anaesthesia, using 3-dimensional analysis methods, with HH-OCT imaging. RNFL analysis plays an important role in the management of glaucoma in adults. This study proposes an optimised protocol for similar assessment to be carried out in children recommending measurements at a radius of 6° from the center of the optic nerve. Pediatric 3-dimensional HH-OCT has the potential to change the way in which infants with optic nerve pathologies are managed.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.