Multiple lines in the header of a Beamer

I found a template that I like. It is a template ready from Radboud University Nijmegen.

The name of the institution is bigger that Radboud University Nijmegen, So I would like to arrange the institution in two lines, how can I do this?

defbeamertemplate*{headline}{ru theme}{%
  leavevmode%
  @tempdimb=2.4375ex%
    multiply@tempdimb bybeamer@sectionmax%
  pgfdeclareimage[height=.9@tempdimb]{logo}{ru_logo}%
  logo{pgfuseimage{logo}}%
  ifdim@tempdimb>0pt%
    advance@tempdimb by 1.125ex%
    begin{beamercolorbox}[wd=.5paperwidth,ht=@tempdimb]{section in head/foot}%
      vbox to@tempdimb{vfilinsertsectionnavigation{.5paperwidth}vfil}%
    end{beamercolorbox}%
    begin{beamercolorbox}[wd=.4paperwidth,ht=@tempdimb,right]{subsection in head/foot}%
      vbox to@tempdimb{vfilvfiltextbf{footnotesizeinsertshortinstitute~~}vfil}%
    end{beamercolorbox}%
    begin{beamercolorbox}[wd=.1paperwidth,ht=@tempdimb,left]{subsection in head/foot}%
      vbox to@tempdimb{vfilinsertlogovfilvfil}%
    end{beamercolorbox}%
  fi%
}

Thank you in advance for any your helpful tip!

vbox to@tempdimb{vfiltextbf{footnotesizeinsertshortinstitute[width={4.5cm},center,respectlinebreaks]}vfil}