In addition, similar efforts have been made with imaging devices; the reported AROCs are 79% to 94% with OCT
4–7,11 in which the diagnosis of PPG is made by using stereophotography
5,7,11 and/or red-free photography,
4,6 and 91% with SLP in which red-free photography, SLP, or OCT is used to diagnose PPG.
8 The 95% CI of the AROC obtained in the current study (73.5%–84.5%) overlaps with those reported by FDT or SWAP and some of those reported with imaging devices; however, it is not appropriate to directly compare AROCs because of considerable differences in the study designs. In the current study, PPGVFs were categorized as the VFs undertaken before conversion to a glaucomatous VF according to Anderson-Patella's criteria; PPGVFs were then discriminated from healthy normal VFs. On the other hand, PPG eyes, not PPGVFs, are distinguished from healthy normal eyes in the previous studies. In addition, the definition of PPG is not always the same across these studies, as detailed above. Moreover, the criteria for classifying glaucomatous VFs also vary. For instance, all conditions included in Anderson-Patella's criteria are used in the studies of Hirashima et al.
11 and Choi et al.,
17 while an abnormal result with GHT or PSD is used in the study by Leeprechanon et al.
16 In the current study, an abnormal VF result was defined as meeting at least one of the three conditions included in Anderson-Patella's criteria.
22 There are only two studies that have analyzed the usefulness of OCT and HRT in diagnosing PPG with longitudinal series of VFs.
5,7 In these studies, patients suspected of having glaucoma, based on the appearance of the optic disc on stereophotography, have been followed up longer than 10 years (VF remained normal throughout the follow-up); it was investigated whether HRT and OCT can discriminate between PPG eyes with stereophotographic evidence of progressive glaucomatous change and those without stereophotographic evidence of progressive glaucomatous change. As a result, the largest AROC is obtained with OCT temporal superior RNFL thickness (88%), followed by OCT global RNFL thickness (86%) and HRT rim area (72%)
7 and average RNFL thickness (89%), followed by inferior hemisphere average RNFL thickness (87%) and inferior quadrant average RNFL thickness (85%).
5