Complications will be evaluated for the intra-operative, early post-operative (up until 1 month) and late post-operative (from 1 month to 1 year) periods. In addition complications will be evaluated as severe (defined as a permanent reduction in vision or complications requiring a surgical intervention) and not severe (complications which resolve with conservative management). As an individual subject may have more than one complication, the number of complications will be compared between the two surgical groups.