Comment on Comparison of ocular response analyzer parameters in primary open angle glaucoma and exfoliative glaucoma patients

Sir,

Recently, Beyazyıldız et al.[1] investigated ocular response analyzer (ORA) parameters in primary open angle glaucoma (POAG), exfoliative glaucoma (EXG) patients and control subjects. We congratulate the authors that they found impressive results with such a simple-design study. The authors found (i) significantly lower corneal hysteresis (CH) and corneal resistance factor (CRF) in EXG patients than other groups, (ii) insignificant difference in CRF between POAG and control subjects, (iii) significant positive correlation between CH and central corneal thickness in EXG patients and control subject but not in POAG patients.

The results really have clinical significance in terms of diagnosis and management. However, we wander whether the authors performed adjustments for multiple comparisons in the statistical analyses. We also wander about the relation between functional parameters and ORA results. Are visual field losses in the groups related with CH and CRF? Does lower CH result in higher mean deviation values despite normal intraocular pressure? What is the correlation between CH/CRF and visual field parameters? The answers of these questions are very important and will increase our understanding about the progression of glaucoma in POAG and EXG patients. We kindly ask to the authors about the answers of these questions.