The 76-year-old media mogul is trying to make a comeback, to win a fourth term as premier.
He was supposed to address a rally in Naples on Friday, but instead spoke to supporters in a video message. Italian media quoted his personal doctor, Alberto Zangrillo, as saying Berlusconi was advised to skip the rally, because he has a posterior vitreous detachment in an eye. In the condition, common in the elderly, a gel-like substance naturally in the eye pulls away from the retina.
Berlusconi and his center-right coalition have been running second in opinion polls before the Feb. 24-25 election, behind the center-left's candidate. Results will be announced Monday, after polls close.