------------------------------
                               UNITED STATES                                OMB APPROVAL
                    SECURITIES AND EXCHANGE COMMISSION             ------------------------------
                          Washington, D.C. 20549                   OMB Number 3235-0145
                                                                   ------------------------------
                                                                   Expires:   February 28, 2009
                                                                   ------------------------------
                                                                   Estimated average burden
                                                                   hours per response . . . 11


                              INITIAL SCHEDULE 13G


                    Under the Securities Exchange Act of 1934


                             Somanetics Corporation
-------------------------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
-------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    834445405
-------------------------------------------------------------------------------
                                 (CUSIP Number)

                                December 31, 2006
-------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

        |x|       Rule 13d-1(b)

                  Rule 13d-1(c)

                  Rule 13d-1(d)


*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).








                                PAGE 1 OF 9 PAGES





----------------------                                    ---------------------
CUSIP No. 834445405                 13G                   Page  2  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           Manulife Financial Corporation

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Canada

-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             -0-
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
--------------------------------------------------------------------------------
    9     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

          None,  except  through its indirect,  wholly-owned  subsidiaries,  MFC
          Global Investment  Management (U.S.A.) Limited, John Hancock Advisers,
          LLC and MFC Global Investment Management (U.S.), LLC
--------------------------------------------------------------------------------
   10     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

          N/A
--------------------------------------------------------------------------------
   11     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

          See line 9 above.
--------------------------------------------------------------------------------
   12     TYPE OF REPORTING PERSON*

          HC
--------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 2 OF 9 PAGES





----------------------                                    ---------------------
CUSIP No. 834445405                 13G                   Page  3  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           MFC Global Investment Management (U.S.A.) Limited

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Canada
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             455
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 455
       With            ---------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           455
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           0.003%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 3 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No. 834445405                 13G                   Page  4  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Advisers, LLC

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             -0-
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              550,000
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            ---------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             550,000
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           550,000
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           4.2%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 4 OF 9 PAGES





----------------------                                    ---------------------
CUSIP No. 834445405                 13G                   Page  5  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           MFC Global Investment Management (U.S.), LLC

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             135,190
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              550,000
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 135,190
       With            ---------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             550,000
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           685,190
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           5.2%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 5 OF 9 PAGES




Attention:  Intentional  misstatements  or omissions of fact constitute  Federal
            criminal violations (See 18 U.S.C. 1001)

   Item 1(a)    Name of Issuer:
                Somanetics Corporation

   Item 1(b)    Address of Issuer's Principal Executive Offices:
                1653 East Maple Road
                Troy, Michigan 48083-4208

   Item 2(a)    Name of Person Filing:
                This filing is made on behalf of Manulife Financial  Corporation
                ("MFC"),  and MFC's  indirect,  wholly-owned  subsidiaries,  MFC
                Global  Investment  Management  (U.S.A.) Limited ("MFC Global"),
                John  Hancock  Advisers,  LLC ("JHA") and MFC Global  Investment
                Management (U.S.), LLC ("MFC Global (U.S.)").

   Item 2(b)    Address of the Principal Offices:
                The principal business offices of MFC and MFC Global are located
                at 200 Bloor Street,  East, Toronto,  Ontario,  Canada, M4W 1E5;
                JHA is located at 601  Congress  Street,  Boston,  Massachusetts
                02210;  and MFC  Global  (U.S.)  is  located  at 101  Huntington
                Street, Boston, Massachusetts 02199.

   Item 2(c)    Citizenship:
                MFC and MFC Global  are  organized  and exist  under the laws of
                Canada.
                JHA and MFC Global (U.S.) are organized and exist under the laws
                of the State of Delaware.

   Item 2(d)    Title of Class of Securities:
                Common Stock

   Item 2(e)    CUSIP Number:
                834445405

   Item 3       If the Statement is being filed  pursuant to Rule  13d-1(b),  or
                13d-2(b), check whether the person filing is a:

                MFC:     (g) (X) Parent  Holding  Company,  in accordance  with
                                 ss.240.13d-1(b)(ii)(G).

                MFC
                Global:  (e) (X) Investment  Adviser registered under ss.203 of
                                 the Investment Advisers Act of 1940.

                JHA:     (e) (X) Investment  Adviser registered under ss.203 of
                                 the Investment Advisers Act of 1940.

                MFC Global
                (U.S.):  (e) (X) Investment  Adviser registered under ss.203 of
                                 the Investment Advisers Act of 1940.

   Item 4       Ownership:

                (a) Amount   Beneficially   Owned:  MFC  Global  has  beneficial
                    ownership of 455 shares of Common Stock,  JHA has beneficial
                    ownership  of 550,000  shares of Common Stock and MFC Global
                    (U.S.) has beneficial  ownership of 685,190 shares of Common
                    Stock.  Through its  parent-subsidiary  relationship  to MFC
                    Global, JHA and MFC Global (U.S.), MFC may be deemed to have
                    beneficial ownership of these same shares.


                                PAGE 6 OF 9 PAGES


               (b)  Percent of Class: Of the 13,156,027 shares outstanding as of
                    October 6, 2006,  according to the issuer's quarterly report
                    on form 10-Q for the  period  ended  August  31,  2006,  MFC
                    Global held 0.003%, JHA held 4.2% and MFC Global (U.S.) held
                    5.2%. The aggregate  percentage held as of December 31, 2006
                    (after  eliminating  double  counting  as a result of shared
                    investment or voting  discretion)  by all reporting  persons
                    was 5.2%.

               (c) Number of shares as to which the person has:

                   (i)  sole power to vote or to direct the vote:
                        MFC  Global  has  sole  power to vote or to  direct  the
                        voting of the  shares of  Common  Stock it  beneficially
                        owns.  MFC  Global  (U.S.)  has sole power to vote or to
                        direct the voting of 135,190  shares of Common  Stock it
                        beneficially owns.

                   (ii) shared power to vote or to direct the vote:
                        JHA has shared  power to vote or to direct the voting of
                        the shares of Common  Stock it  beneficially  owns.  MFC
                        Global  (U.S.) has shared power to vote or to direct the
                        voting of 550,000 shares it beneficially owns.

                   (iii)sole power to dispose or  to direct the disposition of:
                        MFC  Global  has sole  power to dispose or to direct the
                        disposition   of  the   shares   of   Common   Stock  it
                        beneficially  owns.  MFC Global (U.S.) has sole power to
                        dispose or to direct the  disposition  of 135,190 shares
                        of Common Stock it beneficially owns.

                   (iv) shared power to dispose or to direct the disposition of:
                        JHA  has  shared  power  to  dispose  or to  direct  the
                        disposition   of  the   shares   of   Common   Stock  it
                        beneficially owns. MFC Global (U.S.) has shared power to
                        dispose or to direct the  disposition  of 550,000 shares
                        of Common Stock it beneficially owns.

   Item 5       Ownership of Five Percent or Less of a Class:
                Not applicable.

   Item 6       Ownership of More than Five Percent on Behalf of Another Person:
                Not applicable.

   Item 7       Identification and Classification of the Subsidiary which
                Acquired the Security Being Reported on by the Parent Holding
                Company:
                See Items 3 and 4 above.

   Item 8       Identification and Classification of Members of the Group:
                Not applicable.

   Item 9       Notice of Dissolution of a Group:
                Not applicable.

   Item 10      Certification:
                By signing below the undersigned certifies that, to the best of
                its knowledge and belief, the securities referred to above were
                acquired  and are held in the  ordinary  course of business and
                were not  acquired  and are not held for the purpose of or with
                the effect of changing or influencing the control of the issuer
                of the  securities  and were not  acquired  and are not held in
                connection with or as a participant in any  transaction  having
                that purpose or effect.


                             PAGE 7 OF 9 PAGES


                                 SIGNATURE

    After reasonable  inquiry and to the best of its knowledge and belief,  each
of the undersigned certifies that the information set forth in this statement is
true, complete and correct.


                                Manulife Financial Corporation


                                By:      /s/ Scott A. Lively
                                Name:    Scott A. Lively
Dated: February 8, 2007         Title:   Attorney in Fact*


                                MFC Global Investment Management (U.S.A) Limited


                                By:      /s/ Gordon Pansegrau
                                Name:    Gordon Pansegrau
Dated: February 8, 2007         Title:   General Counsel, Chief Compliance
                                         Officer & Secretary


                                John Hancock Advisers, LLC


                                By:      /s/ Francis V. Knox Jr.
                                Name:    Francis V. Knox Jr.
Dated: February 8, 2007         Title:   Vice President and Chief Compliance
                                         Officer


                                MFC Global Investment Management (U.S), LLC


                                By:      /s/ Francis V. Knox Jr.
                                Name:    Francis V. Knox Jr.
Dated: February 8, 2007         Title:   Vice President and Chief Compliance
                                         Officer


* Signed  pursuant to a Power of Attorney dated January 31, 2007 included as an
  Exhibit to Schedule 13G filed with the Securities and Exchange  Commission by
  Manulife Financial Corporation on February 1, 2007.


                                PAGE 8 OF 9 PAGES


EXHIBIT A
                             JOINT FILING AGREEMENT
                             ----------------------

     Manulife Financial  Corporation,  MFC Global Investment Management (U.S.A.)
Limited, John Hancock Advisers, LLC and MFC Global Investment Management (U.S.),
LLC agree that the Initial  Schedule  13G to which this  Agreement  is attached,
relating to the Common Stock of  Somanetics  Corporation,  is filed on behalf of
each of them.


                                Manulife Financial Corporation


                                By:      /s/ Scott A. Lively
                                Name:    Scott A. Lively
Dated: February 8, 2007         Title:   Attorney in Fact*


                                MFC Global Investment Management (U.S.A) Limited


                                By:      /s/ Gordon Pansegrau
                                Name:    Gordon Pansegrau
Dated: February 8, 2007         Title:   General Counsel, Chief Compliance
                                         Officer & Secretary


                                John Hancock Advisers, LLC


                                By:      /s/ Francis V. Knox Jr.
                                Name:    Francis V. Knox Jr.
Dated: February 8, 2007         Title:   Vice President and Chief Compliance
                                         Officer


                                MFC Global Investment Management (U.S), LLC


                                By:      /s/ Francis V. Knox Jr.
                                Name:    Francis V. Knox Jr.
Dated: February 8, 2007         Title:   Vice President and Chief Compliance
                                         Officer


* Signed  pursuant to a Power of Attorney dated January 31, 2007 included as an
  Exhibit to Schedule 13G filed with the Securities and Exchange  Commission by
  Manulife Financial Corporation on February 1, 2007.


                                PAGE 9 OF 9 PAGES