Repeatability of automatic measurements by a new spectral domain optical coherence biometer and agreement with a validated biometer.

PURPOSE: To evaluate the repeatability of measurements obtained with a new spectral-domain optical coherence tomography-based biometer (Colombo IOL II, Moptim) and assess their agreement with those provided by the IOLMaster 700 (Zeiss).

SETTING

I.R.C.C.S. Bietti Foundation, Rome, Italy.

DESIGN

Prospective evaluation of diagnostic test.

METHODS

Patients underwent 3 consecutive scans with the Colombo IOL II and 1 with the IOLMaster 700. Two groups were analyzed: Group A included a series of consecutive patients undergoing phacoemulsification and Group B a series of subjects with a clear lens. Axial length (AL), keratometry, keratometric astigmatism, anterior chamber depth (ACD), lens thickness (LT), corneal diameter (CD), central corneal thickness (CCT) and retinal thickness (RT) were analyzed. The within-subject standard deviation (Sw), intrasession test variability, coefficient of variation (CoV) and intraclass correlation coefficient (ICC) were calculated for repeatability analysis. 95% limits of agreement were calculated to assess agreement with the IOLMaster 700.

RESULTS

Ninety-six unoperated eyes of 96 patients were enrolled (Group A: 45 Group B: 51). The CoV was low for most parameters, as it ranged between 0.04% (AL) to 4.47% (RT) in Group A and from 0.03% (AL) to 2.23% (LT) in Group B. Keratometric astigmatism measurements were less repeatable. Good agreement with the IOLMaster 700 was found for K, LT and AL, whereas the mean ACD was higher by 0.07±0.11 mm with the Colombo IOL II (p <0.0001).

CONCLUSION

Measurements by the Colombo IOL II showed high repeatability and good agreement with those provided by the IOLMaster 700.