Got injured on his back while filming the upcoming movie Syriana, George Clooney had to have a surgery on his neck that caused him to have a painful headache brought on by fluid leaking out of his spinal column. This then became one reason that caused Clooney's absence from the promotional duties for Ocean's Twelve sequel.
After sometimes wearing a neck brace, Clooney can now feel relieved after the doctors, who had had some diagnosis, performed 'spinal cap' surgery for his last stages of recovery. Hope you get better soon bro!!!