Background
Fibrosis is the primary cause of failure following glaucoma surgery. Wound healing modulation with 5-fluorouracil and mitomycin-C is routinely employed to reduce ocular fibrosis and improve surgical success rates; however, it also increases the risk of postoperative complications.
Case presentation
A 59-year-old patient with a family history of glaucoma presented a decade after bilateral trabeculectomy with an intraocular pressure (IOP) of 30 mmHg in the right eye and 42 mmHg in the left eye. Both eyes underwent multiple cyclophotocoagulations in the past and showed ocular surface inflammation due to eyedrop intolerance as well as scarred blebs without scleral thinning. Simultaneous bilateral bleb needling reduced IOP to 7 mmHg on the right eye and 12 mmHg on the left eye. The postoperative course of the right eye was favorable with a stable IOP at the low teens. However, IOP of the left eye rose to 34 mmHg within 3 days, accompanied by a uveal prolapse into the bleb. A subsequent vitrectomy with Tutopatch® and anterior chamber washout was performed after 10 days, followed by implantation of the novel Paul® Glaucoma Drainage Implant after sufficient scleral healing. This resulted in a postoperative IOP of 8 mmHg. After 12 months, no eyedrops were required, there were no signs of ocular surface inflammation, and the IOP was stable at 13 mmHg in the right eye and 12 mmHg in the left eye.
Conclusion
This case highlights a rare occasion of scleral thinning leading to perforation with uveal prolapse after needling, 10 years post-trabeculectomy. Likely causes include the use of antimetabolites, cyclodestructive procedures, and chronic conjunctival inflammation from eyedrops. Although needling is typically low-risk, it can lead to complications similar to trabeculectomy. Preoperative screening for scleral thinning using slit lamp and anterior segment OCT is recommended for high-risk patients. The presented two-stage treatment strategy proved successful in managing this complex case.