Author: Büsra Kose
Co-authors: Ahmet Mehmet Somuncu, Ahmet Duhan Ozbay, Murat Günay, Dilek Uzlu, Mehmet Kola
Abstract
Purpose: It is important to determine the location of retinal vascularization in infants with retinopathy of prematurity (ROP). Zone I defines a circular area with radius twice the estimated distance from the optic disc center to the foveal center and Zone II indicates a ring like area extending nasally from the outer limit of Zone I to the nasal ora serrata along with a similar distance temporally, superiorly, and inferiorly. Moreover, posterior Zone II defines a region that is two disc diameters away from the Zone I border. Importance of posterior Zone II ROP is that it has potential to manifest as a more severe ROP compared to more peripheral Zone II ROP.We realized a hypopigmented area temporal to the fovea during our clinical examinations in infants with ROP which corresponds to posterior Zone II location. The aim of this presentation is to discuss the use of the hypopigmented area temporal to the fovea in ROP infants as a possible indicator to locate posterior Zone II region.
Setting: Karadeniz Technical University Faculty of Medicine, Ophthalmology Department
Method: During ROP screening examinations, evaluation of the distance between the hypopigmented area and optic nerve head was performed by using ultra – wide field (UWF) fundus imaging. Possible association of the location of this hypopigmented area and posterior Zone II border was sought. The area of the hypopigmented region located temporally and its distance from the optic nerve head were calculated.
Results: A total of 204 imaging sessions were performed by using UWF imaging in both eyes of 28 premature infants with ROP. The presence of the hypopigmented area was observed in 199 of 204 fundus images. The mean distance of the hypopigmented area from the optic nerve head was 11.39 ± 0.56 mm. The temporal border of the hypopigmented areas on fundus imagings approximately corresponded with the posterior Zone II location.
Conclusion: Besides the use of either a 20 D or 28 D condensing lens to determine the retinal vascularization border, the hypopigmented area can be an alternative option as an auxiliary marker to determine the border of posterior Zone II region. The hypopigmented area may also be a useful indicator during binocular indirect ophthalmoscopic examination with scleral depression of the temporal region while the optic nerve head is not visible in the examined field.
