Inter-device comparison of retinal sensitivity measurements: the CenterVue MAIA and the Nidek MP-1.

BACKGROUND

Our aim is to compare retinal sensitivity measurements obtained on two microperimeters: the CenterVue MAIA and the Nidek MP-1.

DESIGN

A prospective study was conducted in a private ophthalmology clinic.

PARTICIPANTS

Seventeen individuals with a range of stable macular function were recruited as participants.

METHODS

Microperimetry in one eye with identical test strategy in both devices, with randomized testing order, is used.

MAIN OUTCOME MEASURES

The main outcome measures include differences in mean sensitivity (MS), point-wise sensitivity (PWS) and duration. Limits of agreement (LoA) in MS and pooled PWS were calculated. Concordance in scotoma assessment was analysed by kappa (κ) agreement of local defect classification (LDC), LoA in number of scotomatous loci detected and congruence in scotoma localization (CSL).

RESULTS

Median (interquartile range) MS of the MP-1 and MAIA was 13.3 (5.6-18.1) and 21.2 (14.5-27.0) dB, (P MP-1). Median (interquartile range) duration for the MP-1 and MAIA was 10'28″ (7'17″-11'53″) and 8'46″ (8'30″-9'06″), (P = 0.21). LoA for MS and pooled PWS was 1.4 to 13.3 dB and -3.9 to 18.5 dB. There was moderate agreement between the devices for LDC (weighted κ = 0.55, P < 0.05). LoA in number of scotomatous loci detected was -13 to 18. CSL varied from 0 to 100% and correlated strongly with increasing scotoma size.

CONCLUSIONS

The large LoA and variation in scotoma mapping concordance suggest that the same microperimeter should be used for follow-up examination. We recommend caution in comparing results derived from different types of microperimeters.