EXHIBIT 99.2

                               AMENDMENT NO. 4 TO
                           SECOND AMENDED AND RESTATED
                        PREFERRED SHARE RIGHTS AGREEMENT


         This Amendment No. 4 (this "Amendment") to Second Amended and Restated
Preferred Shares Rights Agreement (the "Rights Agreement") is made effective as
of January 9, 2004. This Amendment is an amendment to the Rights Agreement dated
August 21, 2000 between Cyberonics, Inc., a Delaware corporation (the
"Company"), and Equiserve Trust Company, N.A. (referred to herein as the "Rights
Agent").

                                    RECITALS

         WHEREAS, pursuant to and in compliance with Section 27 of the Rights
Agreement, the Company and the Rights Agent wish to amend the Rights Agreement
as set forth herein;

         NOW THEREFORE, the parties hereto agree as follows:

         Section 1. Amendments. From and after the effective date of this
Amendment, the Rights Agreement shall be amended as follows:

         (a) The definition of "Exempt Person" in Section 1 of the Rights
Agreement shall be amended and restated to read in its entirety as follows:

         "Exempt Person" shall mean (a) the State of Wisconsin Investment Board
         ("SWIB"), unless such entity taken together with its Affiliates and
         Associates shall become the Beneficial Owner of 20% or more of the
         Common Shares outstanding subject to the same exceptions provided in
         the second and third sentences of the definition of "Acquiring Person"
         except that the reference to "15%" in such sentences shall be "20%" in
         the case of SWIB, and (b) Boston Scientific Corporation ("BSX"), unless
         such entity taken together with its Affiliates and Associates shall
         become the Beneficial Owner of 20% or more of the Common Shares
         outstanding subject to the same exceptions provided in the second and
         third sentences of the definition of "Acquiring Person" except that the
         reference to "15%" in such sentences shall be "20%" in the case of BSX,
         or such percentage that is less than 20% as shall be held by BSX as of
         the close of business on the tenth business day following the earlier
         of the expiration or termination of the Hart Scott Rodino Act waiting
         period, but in no event later than February 28, 2004.

         Section 2. Remainder of Agreement Not Affected. Except as set forth in
Section 1 hereof, the terms and provisions of the Rights Agreement shall remain
in full force and effect and are hereby ratified and confirmed.

         Section 3. Authority. Each party represents that such party has full
power and authority to enter into this Amendment, and that this Amendment
constitutes a legal, valid and binding obligation of such party, enforceable
against such party in accordance with its terms.




         Section 4. Definitions, References.

         (a) Unless otherwise specifically defined herein, each term used herein
which is defined in the Rights Agreement shall have the meaning assigned to such
term in the Rights Agreement.

         (b) On and after the effective date of this Amendment (i) all
references in the Rights Agreement, including Exhibits B and C to the Rights
Agreement shall be deemed to refer to the Rights Agreement as amended by this
Amendment, and all prior amendments, and (ii) all references to "hereof,"
"hereunder," "herein," "hereby" and other similar references contained in the
Rights Agreement as well as each reference to "this Agreement" and each other
similar reference contained in the Rights Agreement shall refer to the Rights
Agreement, as amended.

         Section 5. Counterparts. This Amendment may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
shall constitute one and the same agreement.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and attested, all as of the day and year first above written.

                                    CYBERONICS, INC.


                                    By: /s/ Robert P. Cummins
                                       -----------------------------------------
                                        Robert P. Cummins
                                        Chief Executive Officer and President


                                    EQUISERVE TRUST COMPANY, N.A.


                                    By: /s/ Joshua P. McGinn
                                       -----------------------------------------
                                        Joshua P. McGinn
                                        Senior Account Manager
                                        EquiServe Trust Company


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