Effect of Axial Length on Retinal Nerve Fiber Layer Thickness in Children

Abstract

Purpose: To investigate the effect of axial length on peripapillary retinal nerve fiber layer (RNFL) thickness in myopic, hyperopic, and emmetropic eyes in children by Cirrus HD spectral-domain optical coherence tomography (OCT). Methods: Subjects were divided into 3 groups according to their refractive status: myopic (n = 36), emmetropic (n = 30), and hyperopic (n = 28) eyes. The RNFL thickness measurements were taken from the superior, inferior, nasal, and temporal quadrants in the peripapillary region by Cirrus HD OCT. Axial length was also determined for each patient. Results: The myopic eyes had thinner average RNFL and RNFLs of temporal, superior, nasal, and inferior quadrants than the hyperopic eyes (p1<0.001, p2 = 0.004, p3 = 0.011, p4 = 0.006, p5 = 0.033, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of all quadrants had significant negative correlations with axial length. On the other hand, after applying modified Littmann formula for correction of magnification effect, the differences among the 3 groups disappeared (all p>0.05). Conclusions: We have shown that axial length and accordingly refractive status influenced peripapillary RNFL thickness measurements by Cirrus HD OCT in children. Therefore, to make a correct diagnosis of glaucoma or other optic neuropathies in children, either axial length—induced magnification effect should be corrected by ophthalmologists or the current Cirrus HD OCT database should be revised taking axial length into consideration.

Retinal nerve fiber layer thickness in children with β-thalassemia major

“…As previously reported, RNFL measurements might change significantly with ethnicity differences, 34 axial length and refractive error in children 35 . Since both our control and patient groups were from the same geographical region, ethnic difference was not applicable to our results.…”

Assessment of Retinal Nerve Fiber Layer Thickness in Healthy, Full-Term Neonates

“…In particular, the axial length, which increases approximately 7 mm from infancy through adulthood, 52 can influence measured RNFL thicknesses. 53,54 Thus, the neonatal RNFL has unique characteristics that may be properly described only by its own normative dataset.…”

Additive Role of Optical Coherence Tomography Angiography Vessel Density Measurements in Glaucoma Diagnoses

“…), 2) poor centration of the optic disc, 3) segmentation error, and 4) presence of a vitreous floater or epiretinal membrane [21]. Moreover, other confounding factors can affect pRNFLT measurements, including an excessively long axial length (AXL) or large-sized disc [2223242526]. Due to these sources of error, OCT has high sensitivity but relatively lower specificity for glaucoma diagnosis [1920], meaning that reliance on OCT alone (particularly color-coded reports) may result in glaucoma being misdiagnosed in some cases.…”