As per all documents my name is First name: Rajesh Middle name: Krishnan and Surname field is left blank. These documents include Driving Licence and marksheets. However I am yet to apply for a passport and take a date for the GRE.

I read in various forums that having no surname can cause serious trouble for getting I-20s. Please suggest a solution. Time is available to change my name legally but if I add a surname say "Iyer" while applying my passport and all my other documents will carry the name as RAJESH KRISHNAN only and not Iyer Rajesh Krishnan will this be additional trouble? Please suggest some solution as soon as possible. Thanks in advance.