{'fraction_non_alphanumeric': 0.022040816326530613, 'fraction_numerical': 0.013061224489795919, 'mean_word_length': 5.223350253807107, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
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 performed. The effects of buffer and storage variables on the chemical breakdown of MMC in the solutions were studied by means of high-performance liquid chromatography (HPLC).


RESULTS
The survey revealed 33 different variations (including recipes and storage conditions) in the preparation of MMC solutions. Although the majority of the hospitals (15 of 21; 72%) were preparing stable solutions, six of the hospitals (28%) were preparing potentially unstable solutions. The stability of the solutions varied in a nonuniform manner when stored at different temperatures in different buffers.


CONCLUSION
The lack of standardization and quality control of MMC solutions used in filtering surgery allows for the possibility of hospitals preparing unstable solutions.