A comparative study of the chemical stability of various mitomycin C solutions used in glaucoma filtering surgery

Objective: To determine the chemical stability of various mitomycin C (MMC) solutions used in glaucoma filtering surgery. Methods: A survey of the MMC solutions currently in use in 21 hospitals (11 in Canada, 10 in the United States) was conducted. A comparative study of the chemical stability of five different representative solutions was perfo rmed. The effects of buffer and storage variables on the chemical breakdown of MMC in the solutions were studied by means of high-performance liquid c hromatography (HPLC). Results: The survey revealed 33 different variations (including recipes and storage conditions) in the preparation of MMC solutions. Although the majo rity of the hospitals (15 of 21; 72%) were preparing stable solutions, six of the hospitals (28%) were preparing potentially unstable solutions. The s tability of the solutions varied in a nonuniform manner when stored at diff erent temperatures in different buffers. Conclusion: The lack of standardization and quality control of MMC solution s used in filtering surgery allows for the possibility of hospitals prepari ng unstable solutions.