It has been noted that some patients are symptomatic from laser iridectomies that are placed superiorly, even though we have all been taught to place them there due to its position under the lid.  The thinking is that the tear film acts as a prism and that light is reaching the iridectomy. Furthermore, a very small iridectomy can diffract the light and make symptoms worse. A small study demonstrated that a temporal position is better. Go figure!