Cyberonics Gets FDA OK for Small Study  CHICAGO (Reuters) - U.S. regulators, who rejected  Cyberonics Inc.'s &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=CYBX.O target=/stocks/quickinfo/fullquote"&gt;CYBX.O&lt;/A&gt; device to treat depression in  August, cleared the therapy for use in a small study, the  company said on Thursday.