A novel method for controlling the quantity of mitomycin-C applied during filtering surgery for glaucoma

Area of Science:

• Ophthalmology
• Surgical Innovation
• Pharmacology

Background:

• Mitomycin-C sponges are common in glaucoma surgery.
• Standardization of mitomycin-C sponge quantity and size is lacking.
• Variability in drug delivery may impact surgical outcomes.

Purpose of the Study:

• To quantify mitomycin-C in surgeon-prepared sponges versus standardized applicators.
• To assess inter-surgeon variability in mitomycin-C sponge preparation.
• To evaluate the consistency of mitomycin-C delivery for glaucoma surgery.

Main Methods:

• Four surgeons prepared 10 sponges each using their standard methods.
• Schirmer's test graduations (5x5 mm) were used as a control.
• Mitomycin-C quantity was determined by wet-dry weight difference after immersion in 0.2 mg/ml solution.

Main Results:

• Mean mitomycin-C in sponges: 9.6 ± 4.4 µg (range 1.9-17.3 µg), with significant inter-surgeon differences (p<0.0001).
• Mean mitomycin-C in Schirmer's test graduations: 1.7 ± 0.3 µg (range 1.1-2.5 µg), with no significant inter-surgeon differences (p=0.79).
• Significant variability in mitomycin-C quantity was observed between surgeons and even for the same surgeon.

Conclusions:

• Surgeon-prepared mitomycin-C sponges exhibit considerable dose variability, potentially causing complications.
• Standardized applicators, like Schirmer's test graduations, offer improved predictability for mitomycin-C delivery.
• Standardization of mitomycin-C sponge preparation is crucial for consistent glaucoma surgery outcomes.