LAUSR

Background/aims The accuracy of pattern deviation (PD) in estimating the damage to the glaucomatous visual field (VF) in the central 10° in eyes with glaucoma and cataract is unclear. Methods This retrospective study includes 63 eyes of 52 glaucoma patients who successfully underwent cataract surgery or cataract surgery plus iStent implantation. Using the Humphrey Field Analyser 10–2 test, VF was measured within 6 months preoperatively and postoperatively (VFpre and VFpost, respectively). The mean total deviation values in VFpost (mTDpost) indicates glaucomatous damage without cataract and the difference between this value and mean PD values in VFpre (mPDpre) was evaluated (εmPD). The effect of cataract was then evaluated as the difference between mTDpost and mTDpre (ΔmTD), while the effects of mTDpost and ΔmTD on εmPD were also assessed. In addition, based on preoperative visual acuity (VApre) and VFpre, the optimal model for predicting mTDpost was identified. The error of this method (εOptimalModel) was estimated as the difference against mTDpost, which was compared with εmPD. Results Compared with mTDpre, there was a significant improvement in mTDpost (p=0.028). A significant difference was observed between mPDpre and mTDpost (p<0.001). Further, εmPD significantly increased with the increase of mTDpost or ΔmTD (p<0.001 and p=0.0444, respectively). The absolute εOptimalModel was significantly smaller than the absolute εmPD (p<0.001). Conclusions This study warns clinicians that PD of the central 10° VF might underestimate the glaucomatous VF damage with the progression of glaucoma and overestimate it as a cataract progresses.