Fellow Eye With a Dense Cataract and a Functioning Trabeculectomy

Right eye (the seeing eye with a functioning bleb): Do nothing surgically. A functioning bleb with IOP 11 on no medication and a modest field defect is a success - any intraocular surgery risks bleb failure and endophthalmitis. Protect it: avoid routine anterior segment surgery, consider a blebitis warning card, and monitor.

Left eye (the cataract with uncontrolled glaucoma):

• The field defect is threatening fixation and IOP is 26 on two agents, so cataract surgery alone is unlikely to control pressure. Options are phacotrabeculectomy (combined), phacoemulsification alone with intensified drops, or phaco followed by a standalone drainage procedure if pressure remains high.
• In a highly myopic eye with a threat to fixation, a combined phacotrabeculectomy gives the best chance of long-term pressure control and removes the cataract in one anaesthetic, but carries a higher risk of hypotony, choroidal effusion, and bleb-related complications in high myopia.
• A reasonable plan: phacotrabeculectomy with mitomycin C, careful watertight scleral flap closure, and a low threshold for a postoperative course of topical steroid and antibiotic.
• Counsel that surgery controls but does not cure glaucoma; the field defect will not recover, and she will need lifelong follow-up.

Explain:

• Cataract surgery will improve clarity, not the field defect. The nerve damage is permanent; the aim is to stop it getting worse. She should expect better central vision but may still notice a superior field defect, and must keep both eyes monitored.
• Pressure will be lower after combined surgery, but she may still need drops, and she must attend follow-up even when she feels well.
• Risks specific to her: in high myopia, hypotony and choroidal effusion; bleb leak and infection; and the small but real risk of a dropped nucleus or retinal detachment. In her only seeing eye, these risks are weighed against the certainty of progressive glaucomatous loss if untreated.
• The right eye is the priority for protection - she should understand that the left eye is being operated on to preserve it, and the right eye should be shielded and reviewed regularly.
• Set expectations: aim for IOP in the low teens, stable field at 6 and 12 months, and a documented plan for who to call if vision drops or the eye becomes painful/red.

Reasons to deviate:

• If the field defect were not threatening fixation and IOP were controllable on drops, phacoemulsification alone with intensified medical therapy would avoid bleb-related risk in a high-myopic eye.
• If she could not tolerate a bleb or had poor ocular surface/fornix, a glaucoma drainage device or a minimally invasive glaucoma surgery (MIGS) combined with phaco might be preferred - but MIGS gives modest pressure reduction and is unlikely to be enough at IOP 26 with advanced damage.
• If she were monocular with a very high risk of hypotony, a staged approach (phaco first, reassess pressure and field, then trabeculectomy if needed) reduces the risk of a catastrophic complication in the only seeing eye.
• If adherence or follow-up is unreliable, a drainage device may be more robust than a bleb requiring needling and monitoring.

Decision framework: match the pressure target to the stage of damage (lower target for threatened fixation), weigh the risk of hypotony in high myopia, and consider the reliability of follow-up. Document the discussion and the chosen target pressure.