<prompt> What is the normal value of Arden index100-130130-150150-180185  <response>: Results of EOG are interpreted by finding the Arden ratio light size ratio : light peak LP Arden ratio . ___x100 Minimum height of dark troughDT Normal- 185 or above Subnormal - between 185 165 Abnormal - below 165 Reference : anatomy and physiology , Khurana 3rd edition page no 238 