Shevchenko sidelined with broken jaw
"At this time it's impossible to predict when he will be able to make his return. He'll travel to either England or Italy this week to see a specialist," Dynamo's doctor Andriy Shmorgun told the club's website.
The former European Player of the Year, who has battled several minor injuries this season, broke his jaw in Dynamo's 2-0 win over city rivals Arsenal in the Ukrainian Premier League on Saturday.
The 34-year-old former AC Milan and Chelsea striker returned to Dynamo in 2009, a decade after leaving them.
Dynamo face Bulgaria's Litex Lovech in the first leg of the Europa League play-off on Thursday after being knocked out of the Champions League qualifiers by Rubin Kazan earlier this month.