Abstract
Purpose: :
To evaluate the optic nerve head (ONH) planimetry with two different methods, and to investigate the influence of optic/biometric parameters.
Methods: :
Prospective examination of 106 eyes with OCT Stratus and HRT II. After a complete ophthalmologic examination fundus photographs were taken and mean central corneal power (CCP Zeiss IOLMaster), central corneal thickness (CCT, Tomey AL-1000, SD < 5µm), anterior chamber depth (ACD), axial length (AL, Zeiss IOLMaster), and spherical equivalent (SEQ) were measured. The difference between OCT and HRT values was correlated with the biometric data.
Results: :
The size of the ONH did not differ significantly (p=0.78) between OCT and HRT II measurements (OCT=2.28+/-0.58 mm², HRT II=2.27+/-0.54 mm², r=0.686 p<0.001). The excavation values of the ONH differed significantly (p<0.001; OCT=1.29+/-0.76 mm², HRT II=0.97+/-0.57 mm², r=0.604 p<0.001). A good correlation of the CCT, CCP, AL, ACD and SEQ was found with the difference of ONH size (OCT-HRT, r=0.593; p<0.001, ANOVA) and ONH excavation (OCT -HRT, r=0.359; p=0.009, ANOVA).
Conclusions: :
Optic magnification has a significant impact on the papillary planimetry. A correct magnification formula should be applied in the future to offer comparable measurements with different diagnostic glaucoma devices.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical