2Uz. Dr., Kocaeli Derince Eğitim ve Araştırma Hastanesi, Göz Kliniği, Kocaeli, Türkiye
3Doç. Dr., Memorial Hastanesi, Göz Servisi, Kayseri, Türkiye
4Prof. Dr., TOBB ETÜ Hastanesi, Göz Hastalıkları Servisi Purpose: To compare the optic nerve head (ONH) parameters obtained by KOWA three dimensional (3D) non-mydriatic stereoscopic retinal camera (NMRC) and Heidelberg retinal tomograph III (HRT) in healthy subjects.
Materials and methods: In this study, 72 eyes of 36 healthy subjects were enrolled. Kowa 3D NMRC and HRT III examinations were performed to each subject on the same day. Nine ONH parameters, including vertical cup disc ratio, cup area, disc area, rim area, height variation contour, cup volume, rim volume, maximum cup depth, and mean cup depth values of both devices were compared and correlated.
Results: Kowa 3D NMRC and HRT revealed similar values for vertical cup disc ratio, cup volume, and rim volume (p>0.05). However Kowa 3D NMRC signifi cantly overestimated the HRT determined cup area, disc area, height variation contour, and rim area (p<0.001). Kowa 3D NMRC signifi cantly underestimated the HRT determined mean cup depth and maximum cup depth (p<0.001). A statistically signifi cant, high degree correlation was found between the two devices for the vertical cup disc ratio, cup area, disc area, cup volume, maximum cup depth, and mean cup depth (r=0.66-0.83, p<0.001). A statistically signifi cant but low degree correlation was found regarding height variation contour (r=0.29, p=0.01). There was no significant correlation in the measurement of rim volume and rim area (p>0.05).
Conclusion: Most of ONH parameters including vertical cup disc ratio are similar when measured by Kowa 3D NMRC and HRT III. Kowa 3D NMRC is a potential tool for monitoring ONH parameters.
Keywords : Heidelberg retina tomography III, KOWA non-mydriatic retinal camera, optic nerve head