The Hoops goalkeeper missed the 4-1 win over Hearts on the weekend and could be sidelined for Tuesday's meeting with Dundee United and next weekend's League Cup semi-final at Hampden Park against St Mirren as Lennon looks for him to get back to full fitness ahead of next month's Champions League Round of 16 ckash with Juventus.
"Fraser has a problem with his neck. He's trained the last couple of days, but it cramps up. It may be a disc problem," Lennon said.
"We are hoping it can be resolved in the next week to 10 days. He has gone for a scan and we are waiting for the results of that.
"It is nothing serious, but it was enough for us to say 'Don't play in this one', and he could be a doubt for Tuesday as well."