<PAGE>   1

                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

   
                                  FORM 10-Q/A
                               (AMENDMENT NO. 1)
    

                                   (Mark One)

(x)  Quarterly report pursuant to Section 13 or 15(d) of the Securities
      Exchange Act of 1934 For the quarterly period ended FEBRUARY 28, 1997

                                       OR

( )  Transition report pursuant to Section 13 or 15(d) of the Securities
      Exchange Act of 1934 For the transition period from _________ to ________

                         Commission file number 0-19095

                            SOMANETICS  CORPORATION
             (Exact name of registrant as specified in its charter)

          MICHIGAN                                         38-2394784
(State or other jurisdiction of                        (I.R.S. Employer
incorporation or organization)                         Identification No.)

                             1653 EAST MAPLE ROAD,
                                 TROY, MICHIGAN
                                   48083-4208
                    (Address of principal executive offices)
                                   (Zip Code)

                                 (810) 689-3050
              (Registrant's telephone number, including area code)

    Indicate by check mark whether the registrant (1) has filed all reports
    required to be filed by Section 13 or 15(d) of the Securities Exchange
    Act of 1934 during the preceding 12 months (or for such shorter period that
     the registrant was required to file such reports), and (2) has been
           subject to such filing requirements for the past 90 days.

                          Yes _____X_____     No __________

        Number of common shares outstanding at April 11, 1997: 2,285,351





<PAGE>   2


                           PART II OTHER INFORMATION


Item 6.  Exhibits and Reports on Form 8-K

   
<TABLE>
<S>      <C>
         (a)   Exhibits
         
               3(i)     Restated Articles of Incorporation of Somanetics
                        Corporation, incorporated by reference to Exhibit
                        3(i) to the Company's Quarterly Report on Form 10-Q
                        for the quarter ended February 28, 1997.
         
               10.1     Letter Agreement, dated as of February 20, 1997,
                        between Somanetics Corporation and Mitani & Co., LLC,
                        incorporated by reference to Exhibit 10.1 to the
                        Company's Quarterly Report on Form 10-Q for the
                        quarter ended February 28, 1997.
         
               27.1     Financial Data Schedule, incorporated by reference to
                        Exhibit 27.1 to the Company's Quarterly Report on
                        Form 10-Q for the quarter ended February 28, 1997.
         
               27.2     Restated Financial Data Schedule for the fiscal year
                        ended November 30, 1996.
         
               27.3     Restated Financial Data Schedule for the nine-month
                        period ended August 31, 1996.
         
               27.4     Restated Financial Data Schedule for the six-month
                        period ended May 31, 1996.
         
         (b)     Reports on Form 8-K

                 No reports on Form 8-K were filed by the Company during the
                 quarter for which this report is filed.


</TABLE>
    




                                      2
<PAGE>   3


                                   SIGNATURES
   
Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this Amendment No. 1 to report to be signed on its
behalf by the undersigned thereunto duly authorized.
    

                                              Somanetics Corporation
                                              (Registrant)




   
Date: April 17, 1997                          By: /s/ Raymond W. Gunn
      --------------                             --------------------
    
                                              Raymond W. Gunn
                                              Executive Vice President and Chief
                                              Financial Officer (Duly Authorized
                                              and Principal Financial Officer)







                                      3



<PAGE>   4


                                 EXHIBIT INDEX


   
<TABLE>
<CAPTION>
Exhibit                                    Description
-------                                    -----------
<S>     <C>
3(i)    Restated Articles of Incorporation of Somanetics Corporation,
        incorporated by reference to Exhibit 3(i) to the Company's
        Quarterly Report on Form 10-Q for the quarter ended February 28,
        1997.

10.1    Letter Agreement, dated as of February 20, 1997, between
        Somanetics Corporation and Mitani & Co., LLC, incorporated by
        reference to Exhibit 10.1 to the Company's Quarterly Report on
        Form 10-Q for the quarter ended February 28, 1997.

27.1    Financial Data Schedule, incorporated by reference to Exhibit 27.1
        to the Company's Quarterly Report on Form 10-Q for the quarter
        ended February 28, 1997.

27.2    Restated Financial Data Schedule for the fiscal year ended
        November 30, 1996.

27.3    Restated Financial Data Schedule for the nine-month period ended
        August 31, 1996.

27.4    Restated Financial Data Schedule for the six-month period ended
        May 31, 1996.

</TABLE>
    




                                      4