Abstract
Purpose :
Our previously introduced model1 compensating for intersubject variability was applied for the circumpapillary retinal nerve fiber layer (RNFL) values measured with optical coherence tomography (OCT, Cirrus®) in glaucoma suspects with our without prior progressive optic disc (OD) change in a series of at least 4 confocal scanning laser tomography (CSLT) (HRT®III) measurements.
Methods :
48 glaucoma suspects characterized by suspect appearance of the OD but with normal visual field were included. Change during the CSLT follow-up was determined with strict, moderate and liberal criteria of the Topographic Change Analysis2 (Table 1). Multivariate model compensation (MC) as well as age compensation (AC) of RNFL (RNFLMC vs. RNFLAC) was applied to the global, quadrants and clock hour sectors (CHR) of RNFL thickness values. For both we also calculated the normalized minimum deviation (minNDMC and minNDAC) from the expected value, defined as division of the deviation through the model standard deviation. Diagnostic performance of RNFLMC vs RNFLAC was tested with area under the receiver operating characteristic (AUROC) and compared between methods using DeLong’s tests.
Results :
Liberal criteria of HRT progression performed better concerning AUROC than moderate or strict criteria, and present a tendency for better diagnostic separation for MC compared with AC (n.s.) (Table 2). The best performing parameters for MC and AC were minNDMC and the superior quadrant of AC.
Conclusions :
Patients with progressive OD change according to the liberal criteria seem to have glaucoma whereas for the other two criteria they are labeled as (false) negatives. Without statistical significance –possibly due to the small sample size– MC did perform slightly better than AC. Reducing interindividual variability of RNFL measurememts through using a multivariate compensation method might improve detection of preperimetric glaucoma among glaucoma suspects.
1 Pereira I et al. Multivariate Model of the Intersubject Variability of the Retinal Nerve Fiber Layer Thickness in Healthy Subjects. Invest Ophthalmol Vis Sci 2015;56:5290-8
2 Bowd C et al. Performance of confocal scanning laser tomograph Topographic Change Analysis (TCA) for assessing glaucomatous progression. Invest Ophthalmol Vis Sci 2009;50:691–701
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.