Music director Riccardo Muti will be absent when the Chicago Symphony Orchestra makes its much-anticipated Asian tour, beginning January 27. The CSO announced last night that the maestro has a hernia that requires prompt surgery.

Muti, suffering from what looked like the flu, returned to his home in Italy earlier this month after spending a single night in Chicago. He'll remain there for this procedure and a recovery period, which means he'll have missed the entire winter season.

Lorin Maazel, director of the Munich Philharmonic, who has a 40-year history with the CSO, will fill in for part of the tour; the rest TBA.