Q: My itunes was recently updated to 12.4.1.6 and now i can't access internet radio.

iTunes 12 for Mac: Listen to Internet radio - https://support.apple.com/kb/PH19478

May 2016 post with image of Internet Radio in menu - https://discussions.apple.com/message/30210907#30210907

Changes in iTunes Radio with the introduction of Apple Music, August 2015 - https://discussions.apple.com/thread/7197899

If you mean "iTunes Radio":

January 2016 - http://www.macrumors.com/2016/01/29/apple-ceases-free-itunes-radio/ - "Friday January 29, 2016 4:15 am PST by Tim Hardwick

Apple today officially ended free streaming of its iTunes Radio channels worldwide, incorporating the catalogue of stations into its subscription-based Apple Music service."