"It's going to be a long time," Sabine Kehm was quoted as saying.
Her comments came after a former racing driver said Schumacher was beginning to communicate with his eyes.
The claim, made by Phillipe Streiff, was dismissed by Ms Kehm and Schumacher's doctor.
Speaking to Le Parisien newspaper, Mr Streiff said he understood that Schumacher was now recognising his close family and communicating with them using his eyes.
BBC News - Schumacher faces 'long fight' one year after skiing accident
Her comments came after a former racing driver said Schumacher was beginning to communicate with his eyes.
The claim, made by Phillipe Streiff, was dismissed by Ms Kehm and Schumacher's doctor.
Speaking to Le Parisien newspaper, Mr Streiff said he understood that Schumacher was now recognising his close family and communicating with them using his eyes.
BBC News - Schumacher faces 'long fight' one year after skiing accident
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