AbstractASOCT has been used to demonstrate a lack of Schlemm's canal (SC) or its dysgenesis in many Primary Congenital Glaucoma (PCG) eyes, and nearly half of Juvenile Open Angle Glaucoma (JOAG) eyes. There is an increasing evidence that even in adult‐onset POAG, apart from the trabecular meshwork (TM), the post TM structures like the SC and collector channels are also affected which may contribute to the outflow resistance. Absence or dysgenesis of the SC is expected to be associated with a poor outflow facility.We evaluated the response of Selective laser trabeculoplasty (SLT) and correlated the visibility of SC on ASOCT in eyes with JOAG. This is because we had previously observed that only 40% of patients diagnosed with JOAG respond to SLT. In this study, we observed that detection of SC on ASOCT among patients undergoing SLT, (even without having evident angle dysgenesis on gonioscopy) was a significant predictor deciding the response to SLT. Success of SLT was defined as a reduction of IOP by 20% or more from pre‐laser value at 6‐months follow‐up without any further IOP‐lowering medication or surgery. A successful reduction in IOP at six‐month follow‐up was correlated with the extent of angle dysgenesis on ASOCT (ADoA).We observed that presence of SC was associated with 8.3 times greater chances of success of SLT than its absence. Also if the presence of SC was detected in >50% ASOCT scans in one eye, it was associated with 21.4 times greater chances of SLT success (p = 0.009). Hence in vivo imaging of the angle is a non‐invasive method of detecting angle dysgenesis, in the absence of an apparent goniodysgenesis. It may help in selecting potential candidates for SLT (or other angle based surgeries) by predicting possible outcome and thus providing more realistic expectations when advising patients, regarding the likelihood of success /failure of their treatment.