EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/146899
30 EW GLAUCOMA July 2013 February 2011 Anterior segment grand rounds A bleb too far by Steven Safran, MD T his is a 60-year-old woman who had an IOP in the 40s on maximal topical medication in this, her dominant right eye. I performed a MMC trabeculectomy on her and things could not have gone more smoothly. She had an IOP of 10-14 mm Hg right from day one with no need to cut sutures. Her vision was 20/25 postop day one and never dropped below that. She had a diffuse, avascular, quiet bleb with no vessels or inflammation. Unfortunately, her bleb was a bit too diffuse for her liking, as she was bothered cosmetically by the "chemosis like" appearance of her conjunctiva with elevation of the conjunctiva in the inferior, nasal, and temporal quadrants and from a comfort standpoint as this caused a foreign body sensation. At two months postop she developed a dellen secondary to the conjunctival elevation at the nasal limbus. This did not respond to aggressive lubrication and was quite painful to her and continued to progress even after upper and lower lid punctal occlusion was performed. Although her IOP is 12-14 mm Hg on no glaucoma medications, she is unhappy, and I am concerned. Steven G. Safran, MD, ASGR editor Figure 1: Dellen at nasal limbus due to conjunctival elevation Figure 2 and Figure 3. Pictures taken right after the procedure was done. Note the radiofrequency energy application contraction "burns" in the inferior nasal and temporal quadrants. Figure 4 and Figure 5: Here is what the patient looked like a few days later with flattening of the conjunctiva and both the unwanted bleb and dellen completely resolved. Figure 6: Another case of bleb dysesthesia before treatment consulted a trio of superb glaucoma surgeons, Scott Fudemberg, MD, assistant professor, Thomas Jefferson Medical College, Wills Eye Institute, Philadelphia, Jonathan Myers, MD, associate attending surgeon, Wills Eye Institute, Philadelphia, and Oluwatosin Smith, MD, glaucoma specialist, Glaucoma Associates of Texas, Dallas, for insight on how to manage this problem. Dr. Smith commented: "This case poses a real dilemma in the face of what I would call "the glaucoma specialist's dream"—a perfectly functioning glaucoma filtering surgery in terms of IOP and with acceptable bleb morphology combined with an unhappy/dissatisfied patient as a result of discomfort from her very diffuse bleb. "My approach to patients with similar problems would involve graduation from less invasive management options to more invasive treatment modalities including surgery, if indicated. … In the event that lubrication doesn't work, I typically would consider putting additional sutures in the scleral flap transconjunctivally at the slit lamp in the office with 10-0 nylon. My goal with the sutures would be to place them on either edge of the procedure is relatively simple to perform as an initial step, but its efficacy may be dissatisfactory. Another approach is to place compression sutures temporally and nasally, again to sequester the bleb superiorly. The approach is similar to compression sutures performed to treat overfiltration with hypotony ... it may ultimately be necessary to suture the flap closed and place a tube shunt. Placing a patch graft over the flap and a compression suture over the patch graft may be necessary to halt flow through a thin flap in an overfiltering bleb. When I place a tube at the same time as I revise a bleb, I prefer to place an Ahmed Glaucoma Valve [New World Medical, Rancho Cucamonga, Calif.] rather than a Baerveldt Glaucoma Implant [Abbott Medical Optics, Santa Ana, Calif.] with vicryl ligature so that flow is directed posteriorly because I think this helps the scleral flap seal. Communication with the patient is critical in this situation. Any further surgical intervention may cause additional discomfort and risk IOP control." Dr. Myers said: "The perils of bleb-based surgery are well known, and bleb dysesthesia is a difficult example. Seemingly small differences in bleb morphology can create extremely uncomfortable, chronic is- I Figure 7: Case in Figure 6 after treatment. Notice the resolution of the inferior conjunctival elevation that was causing dysesthesia. Source (all): Steven Safran, MD flap, attempting to direct flow posteriorly. "If our goal is not achieved by the above, then more extensive surgical work may be required. Rarely patients may opt to have the trabeculectomy reversed and an alternate glaucoma procedure performed." Dr. Fudemberg's thoughts on this case: "When bleb revision is necessary, I consider a few options. First, autologous blood injection into the temporal and nasal aspect of the bleb may be combined with cryotherapy (sometimes called a "snow cone") to the temporal and nasal aspect of the bleb in an attempt to scar the conjunctiva and sequester the bleb superiorly. This