Trypan Blue for the Assessment of Filtering Bleb Function During Cataract Surgery

Area of Science:

• Ophthalmology
• Glaucoma Surgery
• Cataract Surgery

Background:

• Phacoemulsification may cause bleb failure in patients with prior trabeculectomy.
• No established method exists to predict bleb failure risk after phacoemulsification.
• Trabeculectomy is a surgical procedure to treat glaucoma by creating a new drainage channel for aqueous humor.

Purpose of the Study:

• To investigate the use of trypan blue during cataract surgery to evaluate bleb function.
• To predict postoperative bleb function in eyes with prior trabeculectomy.

Main Methods:

• Prospective, nonrandomized clinical trial involving 14 patients with prior trabeculectomy and mitomycin C.
• Trypan blue instilled into the anterior chamber during phacoemulsification before capsulorhexis.
• Bleb staining categorized as mild or diffuse; patients followed for 1 year for intraocular pressure (IOP) control.

Main Results:

• No significant difference in IOP change between mild and diffuse bleb staining groups (P=0.14).
• A trend towards increased need for IOP-lowering medications in eyes with mild bleb staining (P<0.10).
• No statistically significant difference in decreased bleb function rates at 1-year follow-up.

Conclusions:

• Bleb staining intensity with trypan blue during phacoemulsification is not associated with postoperative IOP changes.
• A trend towards decreased need for IOP-lowering medications was observed in eyes with diffuse bleb staining at 1 year post-cataract surgery.