A 65-year-old patient with open-angle glaucoma is being considered for trabeculectomy. Which factor from the TVT (Tube Versus Trabeculectomy) study most strongly favours choosing a tube shunt over trabeculectomy?
- A Black race with known faster scarring risk
- B Need for very low target IOP (<10 mmHg)
- C Prior penetrating keratoplasty or prior failed trabeculectomy ✓
- D Concurrent phacoemulsification required (combined procedure)
Explanation
The TVT study compared Baerveldt tube shunt versus trabeculectomy with MMC in patients who had prior ocular surgery (previous trabeculectomy or cataract/PKP). The 5-year results showed similar IOP control but trabeculectomy had higher cumulative failure rates in this population due to conjunctival scarring. Current guidelines strongly favour tube shunts (Baerveldt 350 or Ahmed valve) when there is prior failed trabeculectomy, prior PKP (due to risk of corneal graft failure from low IOP fluctuations), or extensive conjunctival scarring from prior surgery. For treatment-naïve eyes, trabeculectomy with MMC remains the gold standard.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.