The Trabeculectomy with Preserflo requires revision when the flow is either too low resulting in higher IOP or too high resulting in hypotony. The limbal conjunctival wound must be opened carefully to avoid damage to the device. The Preserflo can be removed from the sclerostomy and wound closed with 10/0 nylon if further mitomycin C is applied. The stent can be replaced via the same or a new sclerostomy created. According to the flow, a 10/0 nylon can be placed intraluminally.  It is best to advance slightly beyond the tip into the anterior chamber in case there is slight withdrawal of the nylon during closure. The suture can then be buried in a corneal pocket anterior to the limbus. This can easily be recovered post-operatively with a bent tip 25G needle if necessary to drop the IOP further. This can be combined with subconjunctival 5FU. Post-revision, topical steroids can be used to control the inflammation and healing response.