Abstract
Abstract: :
Purpose: To evaluate the relationship between the optic disc measurements generated by confocal scanning laser ophthalmoscopy (CSLO) and optical coherence tomography (OCT). Methods: Fifty–two eyes in 27 non–glaucomatous patients were scanned with CSLO– TopSSTM and OCT–OCT 3000TM. The relationship between the four optic disc measurements disc area (DA), cup area(CA), neuroretinal rim area (NRRA) and cup–disc area ratio (CDAR) generated by CSLO and OCT were evaluated, and the relationship between these measurements and the tilt of the optic disc was assessed. The horizontal (HD) and vertical diameters (VD) of the optic disc were measured from the disc photograph, CSLO and OCT, and then the ratios HD:VD (HD/VD) were compared. Results: : There was good correlation in the DA, CA and CDAR between the OCT and CSLO measurements. In the eyes with a tilt more than 4 degrees, the DA and NRRA were larger, and the CDAR smaller when measured by OCT, than those measured by CSLO, but the CA showed no difference between the two measurement systems. However in the eyes with a tilt less than 4 degrees, there were no significant differences in the disc variables between the measurements obtained by OCT and CSLO. The HD/VD measured from the disc photographs showed good correlation with those measured by CSLO (r=0.755, p<0.001), but a poor correlation with those measured by OCT in the eyes with a tilt of more than 4 degrees (r=0.393, p=0.010). Conclusions: : Although CSLO and OCT measurements of the optic disc were highly correlated, the discrepancy becomes prominent in eyes with a highly tilted disc. Therefore analysis of the optic nerve head by OCT needs to be cautiously interpreted in eyes with a highly tilted disc.
Keywords: optic disc • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • shape and contour