In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: RESULTS : During the 3 - year follow - up , 71 . 0 % of implanted eyes had an IOP increase of 10 mm Hg or more than baseline and 55 . 1 % , 24 . 7 % , and 6 . 2 % of eyes reached an IOP of 30 mm Hg or more , 40 mm Hg or more , and 50 mm Hg or more , respectively .
### Output Text:
RESULTS : During the 3 - year follow - up , 71 . 0 % of implanted eyes had an IOP increase of 10 mm Hg or more than baseline and 55 . 1 % , 24 . 7 % , and 6 . 2 % of eyes reached an IOP of 30 mm Hg or more , 40 mm Hg or more , and 50 mm Hg or more , respectively . 