I have applied for Visitor VISA extension for my parents on 4/4/2013. Their I94 is about to expire on 5/14/2013.The reason stated was for pleasure and they wanted to visit other cities in USA.Due to recent travels my mother had some health issue. She has Spondylitis and suffering with sever back and neck pain.Doctor suggested to take complete bed rest and prescribed physiotherapy for 10 weeks. He advised to avoid any kind of travel for next few weeks.Now, as the reason of extension has changed, I would like to update USCIS of the change in reason for extension. Doctor is willing to provide written explanation of the situation so that USCIS understands the necessity of extension. Would this help me in getting successfull extension ?Do they issue RFE for any case before making a decision ( If in case Denying the application ) ?