Icon for unread/updated tickets

In the dashboard, it's really difficult to known if someone have added comments or changes (status..), I need to click many time on the ticket to see if I'm still the last one to have commented it.

May be a clean solution should be to show an icon on the lines of the dashboard, to said someone have added a comment after me or made changes on the ticket. This could help me to see which ticket I need to click.

Thanks!