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


                                  SCHEDULE 13G


             INFORMATION STATEMENT PURSUANT TO RULES 13D-1 AND 13D-2
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934

                               (AMENDMENT NO. 2 )1
                                                 -



                          ASPECT MEDICAL SYSTEMS, INC.
--------------------------------------------------------------------------------
                                (Name of Issuer)


                     Common Stock, $0.01 par value per share
--------------------------------------------------------------------------------
                         (Title or Class of Securities)


                                    045235108
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                                 (CUSIP Number)


                                December 31, 2003
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             (Date of Event Which Requires Filing of this Statement)



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

     [_]  Rule 13d-1(b)
     [X]  Rule 13d-1(c)
     [_]  Rule 13d-1(d)

__________________________________

     1 / 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).

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CUSIP NO. 045235108                   13G                            PAGE 2 OF 6
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  1     NAMES OF REPORTING PERSONS
        S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

        Boston Scientific Corporation
------- ------------------------------------------------------------------------
  2     CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
                                                                         (a) [_]
        N/A                                                              (b) [_]
------- ------------------------------------------------------------------------
  3     SEC USE ONLY


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

        The State of Delaware
------- ------------------------------------------------------------------------
                     5     SOLE VOTING POWER

                           3,855,708
  NUMBER OF        ------- -----------------------------------------------------
   SHARES            6     SHARED VOTING POWER
BENEFICIALLY
  OWNED BY                 0
    EACH           ------- -----------------------------------------------------
  REPORTING          7     SOLE DISPOSITIVE POWER
   PERSON
    WITH                   3,855,708
                   ------- -----------------------------------------------------
                     8     SHARED DISPOSITIVE POWER

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

        3,855,708
------- ------------------------------------------------------------------------
  10    CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
        (SEE INSTRUCTIONS)   [_]
        N/A
------- ------------------------------------------------------------------------
  11    PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

        19.8%
------- ------------------------------------------------------------------------
  12    TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

        CO
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CUSIP NO. 045235108                   13G                            PAGE 3 OF 6
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ITEM 1(A).  NAME OF ISSUER:

            Aspect Medical Systems, Inc,. a Delaware corporation (the "Company")



ITEM 1(B).  ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:

            141 Needham Street
            Newton, MA  02464



ITEM 2(A).  NAME OF PERSON FILING:

            Boston Scientific Corporation



ITEM 2(B).  ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:

            One Boston Scientific Place
            Natick, MA  01760-1537



ITEM 2(C).  CITIZENSHIP:

            The State of Delaware



ITEM 2(D).  TITLE OF CLASS OF SECURITIES:

            Common Stock, $0.01 par value per share, (the "shares")



ITEM 2(E).  CUSIP NUMBER:

            045235108

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CUSIP NO. 045235108                   13G                            PAGE 4 OF 6
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ITEM 3.     IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR 13D-2(B),
            CHECK WHETHER THE PERSON FILING IS A:

            (a) [ ] Broker or dealer registered under section 15 of the Act (15
                    U.S.C. 78o).

            (b) [ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C.
                    78c).

            (c) [ ] Insurance company as defined in section 3(a)(19) of the Act
                    (15 U.S.C. 78c).

            (d) [ ] Investment company registered under section 8 of the
                    Investment Company Act of 1940 (15 U.S.C 80a-8).

            (e) [ ] An investment adviser in accordance with
                    ss.240.13d-1(b)(1)(ii)(E);

            (f) [ ] An employee benefit plan or endowment fund in accordance
                    with ss.240.13d-1(b)(1)(ii)(F);

            (g) [ ] A parent holding company or control person in accordance
                    with ss. 240.13d-1(b)(1)(ii)(G);

            (h) [ ] A savings associations as defined in Section 3(b) of the
                    Federal Deposit Insurance Act (12 U.S.C. 1813);

            (i) [ ] A church plan that is excluded from the definition of an
                    investment company under section 3(c)(14) of the Investment
                    Company Act of 1940 (15 U.S.C. 80a-3);

            (j) [ ] Group, in accordance with ss.240.13d-1(b)(1)(ii)(J).



ITEM 4.     OWNERSHIP:

            (a)     Amount beneficially owned: 3,855,708 shares
            (b)     Percent of class: 19.8%
            (c)     Number of shares as to which such person has:
                    (i)   Sole Power to vote or to direct the vote:
                          3,855,708
                    (ii)  Shared power to vote or to direct the vote:
                          0
                    (iii) Sole power to dispose or to direct the disposition of:
                          3,855,708
                    (iv)  Shared power to dispose or to direct the disposition
                          of: 0



ITEM 5.     OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:

            If this statement is being filed to report the fact that as of the
            date hereof the reporting person has ceased to be the beneficial
            owner of more than five percent of the class of securities, check
            the following: [_]

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CUSIP NO. 045235108                   13G                            PAGE 5 OF 6
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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:

            Not applicable.



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 I certify that, to the best of my knowledge and
            belief the securities referred to above 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 an were not
            acquired and are not held in connections with or as a participant in
            any transaction having that purpose or effect.

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CUSIP NO. 045235108                   13G                            PAGE 6 OF 6
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                                    SIGNATURE

     After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.




                                             February 17, 2004
                                             -----------------------------------
                                             (Date)



                                             By: /s/ Lawrence J. Knopf
                                                 -------------------------------
                                             Name:  Lawrence J. Knopf
                                             Title: Vice President and Assistant
                                                    General Counsel