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                                                                   EXHIBIT 10.18

                          SPECIAL TERMINATION AGREEMENT

     THIS SPECIAL TERMINATION AGREEMENT ("Agreement") is made and entered into
to be effective as of April 1, 2002, by and between Advanced Neuromodulation
Systems, Inc., a Texas corporation (the "Company"), and Christopher G. Chavez
(the "Executive") (together, referred to as the "parties").

     The Executive is currently serving as the Company's President and Chief
Executive Officer.

     The Executive possesses an intimate knowledge of the business and affairs
of the Company, its policies, methods, personnel and plans for the future and
has acquired contacts of considerable value to the Company.

     The Board of Directors of the Company (the "Board") recognizes that the
Executive's contribution to the growth and success of the Company has been
substantial and wishes to offer an inducement to the Executive to remain in the
employ of the Company.

     NOW, THEREFORE, in consideration of the foregoing and of the respective
covenants and agreements of the parties herein contained, the parties agree as
follows:

     1. Term. The term of this Agreement shall continue until the earlier of (i)
the expiration of the third anniversary of this Agreement, (ii) the Executive's
death, or (iii) the Executive's earlier voluntary retirement; provided, however,
that, on each anniversary date of this Agreement or any extension, this
Agreement, the Term and the periods referenced in Section 3 shall automatically
be extended for an additional year unless, not later than 90 calendar days prior
to such anniversary date, the Company shall have given written notice to the
Executive that it does not wish to have the term extended.

     2. Definitions.

     (a) Acquiring Person: An "Acquiring Person" shall mean any person (as
defined in Section 2(d)(iv) of this Agreement) that, together with all
Affiliates and Associates of such person, is or becomes the beneficial owner of
50% or more of the outstanding Common Stock. The term "Acquiring Person" shall
not include the Company, any subsidiary of the Company, any employee benefit
plan of the Company or any subsidiary of the Company, or any person holding
Common Stock for or pursuant to the terms of any such plan. For the purposes of
this Agreement, a person who becomes an Acquiring Person by acquiring beneficial
ownership of 50% or more of the Common Stock at any time after the date of this
Agreement shall continue to be an Acquiring Person whether or not such person
continues to be the beneficial owner of 50% or more of the outstanding Common
Stock.

     (b) Affiliate and Associate. "Affiliate" and "Associate" shall have the
respective meanings ascribed to such terms in Rule 12b-2 of the General Rules
and Regulations under the Securities Exchange Act of 1934, as amended (the
"Exchange Act") in effect on the date of this Agreement.

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     (c) Change in Control. A "Change in Control" of the Company shall have
occurred if at any time during the term of this Agreement any of the following
events shall occur:

(i) any consolidation, merger or other reorganization of the Company in which
the Company is merged, consolidated or reorganized into or with another
corporation or other legal person or pursuant to which shares of the Company's
stock are converted into cash, securities or other property, other than a merger
of the Company in which the holders of the Company's common stock immediately
prior to the merger own more than 50% of the common stock of the surviving
corporation or its ultimate parent immediately after the merger;

(ii) any sale, lease, exchange or other transfer (or in one transaction or a
series of related transactions) of all or substantially all of the assets of the
Company and as a result of such transaction the holders of the Company's common
stock immediately prior thereto own less than 50% of the common stock of such
transferee or its ultimate parent immediately after such transaction;

(iii) any liquidation or dissolution of the Company or any approval by the
stockholders of the Company of any plan or proposal for the liquidation or
dissolution of the Company;

(iv) any person (including any "person" as such term is used in Section 13(d)(3)
or Section 14(d)(2) of the Exchange Act), has become an Acquiring Person;

(v) if at any time, the Continuing Directors then serving on the Board cease for
any reason to constitute at least a majority thereof;

(vi) any occurrence that would be required to be reported in response to Item
6(e) of Schedule 14A of Regulation 14A or any successor rule or regulation
promulgated under the Exchange Act; or

(vii) such other events that cause a change in control of the Company;

          provided, however, that a Change in Control of the Company shall not
          be deemed to have occurred as the result of any transaction having one
          or more of the foregoing effects if such transaction is proposed by,
          and includes a significant equity participation (i.e., an aggregate of
          at least 50% of the then outstanding common equity securities of the
          Company immediately after such transaction which are entitled to vote
          to elect any class of Directors) of, the Executive officers of the
          Company as constituted immediately prior to the occurrence of such
          transaction or any Company employee stock ownership plan or pension
          plan.

     (d) Code. The "Code" shall mean the Internal Revenue Code of 1986, as
amended.

     (e) Continuing Director. A "Continuing Director" shall mean a Director of
the Company who (i) is not an Acquiring Person, an Affiliate or Associate, a
representative of an Acquiring Person or nominated for election by an Acquiring
Person, and (ii) was either a member of the Board of Directors of the Company on
the date of this Agreement or subsequently became a Director of the Company and
whose initial election or initial nomination for election by the Company's
stockholders was approved by at least two-thirds of the Continuing Directors
then on the Board of Directors of the Company.

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     (f) Severance Compensation. The "Severance Compensation" shall be a lump
sum amount equal to 299% of the sum of (A) the highest annual salary of the
Executive in effect at any time during the Term of this Agreement, or the salary
of the Executive in effect immediately prior to the Change in Control, whichever
is the larger amount, plus (B) the amount of the bonus or incentive compensation
targeted for payment to the Executive for the fiscal year during which the
Change in Control occurs.

     (g) Termination Date. The "Termination Date" shall be the date upon which
the Change in Control occurs.

3.   Rights of Executive Upon Change in Control.

     (a) Subject to paragraph 5 below, the Company shall pay the Severance
Compensation to the Executive within ten days following the Termination Date in
lieu of compensation to the Executive for periods subsequent to the Termination
Date, but without affecting the other rights of the Executive at law or in
equity. In addition, the Company shall pay the Executive a job search lump sum
payment of $25,000 within ten days following the Termination Date.

     (b) If the amounts due to the Executive in connection with a Change in
Control under this Agreement (considering amounts due under other agreements,
plans or arrangements) would result in an "excess parachute payment" within the
meaning of Section 280G of the Code, then the Company shall pay to Executive an
additional amount of cash (a "Gross-Up Payment") equal to the amount necessary
to cause the amount of the aggregate after-tax compensation and benefits
received by the Executive here-under (after payment of the excise tax under
Section 4999 of the Code with respect to any excess parachute payment, and any
state and federal income and employment taxes with respect to the Gross-Up
Payment) to equal the aggregate after-tax compensation and benefits the
Executive would have received if Sections 280G and 4999 of the Code had not been
enacted. A nationally recognized public accounting firm selected by the Company
shall initially determine, at the Company's expense, whether an "excess
parachute payment" will be made to Executive, and if so, the amount of the
Gross-Up Payment. In the event of a subsequent claim by the Internal Revenue
Service that, if successful, would result in Executive's liability for an excise
tax under Section 4999 of the Code in excess of the amount covered by any
previous Gross-Up Payment, the Executive shall promptly notify the Company in
writing of such claim. If the Company elects to contest such claim, it shall so
notify the Executive and shall bear and pay directly or indirectly all costs and
expenses of contesting the claim (including additional interest and penalties
incurred in connection with such action), and shall indemnify and hold Executive
harmless, on an after-tax basis, for any excise, income, or employment tax,
including interest and penalties with respect thereto, imposed as a result of
the Company's payment of costs of the contest. Executive shall cooperate fully
with the Company in the defense of any such IRS claim. If, as a result of the
Company's action with respect to a claim, Executive receives a refund of any
amount paid by the Company with respect to such claim, Executive shall promptly
pay such refund to the Company. In the event the IRS claim is finally determined
to result in the imposition of additional excise tax under Section 280G of the
Code on Executive, the Company shall make an additional Gross-Up Payment with
respect to any such additional excise tax.

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     (c) The payment of Severance Compensation by the Company to the Executive
shall not affect any other rights and benefits of the Executive provided by the
Company, whether currently or in the future, prior to the Termination Date,
which rights shall be governed by the terms thereof. The Company shall provide
to the Executive through his Termination Date group insurance benefits,
retirement benefits, and other benefits substantially similar to those which the
Executive was receiving or entitled to receive immediately prior to the Change
of Control Date, subject to any changes required to comply with changes in the
law, and subject to changes in carriers in the ordinary course of business.

     (d) The Company shall have no right of set-off or counterclaim in respect
of any claim, debt or obligation against any payment or benefit to or for the
benefit of the Executive provided for in this Agreement.

     (e) Without limiting the rights of the Executive at law or in equity, if
the Company fails to make any payment required to be made hereunder on a timely
basis, the Company shall pay interest on the amount thereof on demand at an
annualized rate of interest equal to 120% of the then applicable Federal short
term rate determined under Section 1274(d) of the Code, compounded semi-annually
(but in no event shall such interest exceed the highest lawful rate).

     4. No Mitigation Required. In the event that the Company is required to pay
the Severance Compensation under this Agreement, the Executive shall not be
obligated to mitigate his damages nor the amount of any payment provided for in
this Agreement by seeking other employment or otherwise, and the acceptance of
employment elsewhere after termination shall in no way reduce the amount of
Severance Compensation payable hereunder.

     5. Release. In consideration for the protection and benefits provided for
under this Agreement, at the Company's request, Employee hereby agrees to
execute a release of all claims against the Company or any of its affiliates,
directors, officers, employees, agents and benefit plans, in form and substance
satisfactory to the Company. Payment of the benefits under Section 3(a) is
expressly conditioned on Employee's execution of such release if the Company so
requests.

     6. Successors: Binding Agreement.

     (a) The Company will require any successor and any corporation or other
legal person (including any "person" as defined in Section 2(d)(iv) of this
Agreement) which is in control of such successor (as "control" is defined in
Regulation 230.405 or any successor rule or regulation promulgated under the
Securities Act of 1933, as amended) to all or substantially all of the business
and/or assets of the Company (by purchase, merger, consolidation or otherwise),
by agreement in form and substance satisfactory to the Executive, to expressly
assume and agree to perform this Agreement in the same manner and to the same
extent that the Company would be required to perform it if no such succession
had taken place. Failure of the Company to obtain such agreement prior to the
effectiveness of any such succession shall

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be a material breach of this Agreement by the Company. Notwithstanding the
foregoing, any such assumption shall not, in any way, affect or limit the
liability of the Company under the terms of this Agreement or release the
Company from any obligation hereunder. As used in this Agreement, "Company"
shall mean the Company and any successor to its business and/or all or part of
its assets, which executes and delivers the agreement provided for in this
Section 6 or which otherwise becomes bound by all the terms and provisions of
this Agreement by operation of law.

     (b) This Agreement and all rights of the Executive here under shall inure
to the benefit of and be enforceable by the Executive's personal or legal
representatives, executors, administrators, successors, heirs, distributees,
devisees and legatees.

     7. Notice. The Company shall give written notice to Executive within thirty
days after any Change in Control. Failure to give such notice shall constitute a
material breach of this Agreement. For purposes of this Agreement, notices and
all other communications provided for in the Agreement shall be in writing and
shall be deemed to have been duly given when delivered or received after being
mailed by United States registered mail, return receipt requested, postage
prepaid, addressed as follows:

     If to the Executive: Christopher G. Chavez
                          2900 Cedar Ridge Dr.
                          McKinney, Texas 75070

     If to the Company:   Advanced Neuromodulation Systems, Inc.
                          6501 Windcrest Drive, Suite 100
                          Plano, Texas 75024

or to such other address as any party may have furnished to the other in writing
in accordance herewith, except that notices of chance of address shall be
effective only upon receipt.

     8. Miscellaneous. No provision of this Agreement may be modified, waived or
discharged unless such waiver, modification or discharge is agreed to in writing
signed by the Executive and the Company. No waiver by either party of, or
compliance with, any condition or provision of this Agreement to be performed by
such other party shall be deemed a waiver of similar or dissimilar provisions or
conditions at the same or at any prior or subsequent time. No agreements or
representations, oral or otherwise, express or implied, unless specifically
referred to herein with respect to the subject matter of this Agreement have
been made be either party which are not set forth expressly in this agreement.
THE VALIDITY, INTERPRETATION, CONSTRUCTION AND PERFORMANCE OF THIS AGREEMENT
SHALL BE GOVERNED BY THE SUBSTANTIVE LAWS OF THE STATE OF TEXAS, WITHOUT REGARD
TO PRINCIPLES OF CONFLICTS OF LAW.

     9. Validity. The invalidity or unenforceability of any provision or
provisions of this Agreement shall not affect the validity or enforceability of
any other provision of this Agreement, which shall remain in full force and
effect.

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     10. Counterparts. This Agreement may be executed in several counterparts,
each of which shall be deemed to be an original but all of which together will
constitute one and the same instrument.

     11. Employment Rights. Nothing implied in this Agreement shall create any
right or duty on the part of the Company or the Executive to have the Executive
remain in the employment of the Company prior to any Change in Control.
Notwithstanding any other provision hereof to the contrary and subject to the
terms of the Employment Agreement between the Company and the Executive dated as
of April 1, 2002, the Executive may, at any time during the Term of this
Agreement, upon the giving of 30 days prior written notice, terminate his
employment hereunder. If this Agreement or the employment of the Executive is
terminated under circumstances in which the Executive is not entitled to any
Severance Compensation, the Executive shall have no further obligation or
liability to the Company hereunder or otherwise with respect to his prior or any
future employment by the Company.

     12. Withholding of Taxes. The Company may withhold from any amounts payable
under this Agreement all federal, state, city or other taxes as shall be
required pursuant to any law or government regulation or ruling; provided,
however, that no withholding pursuant to Section 4999 of the Code shall be made
unless, in the opinion of tax counsel selected by the Company's independent
accountants and acceptable to the Executive, such withholding relates to
payments which result in the imposition of an excise tax pursuant to Section
4999 of the Code.

     13. Legal Fees and Expenses. It is the intent of the Company that the
Executive not be required to incur the expenses associated with the enforcement
of his rights under this Agreement by litigation or other legal action because
the cost and expense thereof would substantially detract from the benefits
intended to be extended to the Executive in this Agreement. Accordingly, if it
should appear to the Executive that the Company has failed to comply with any of
its obligations under the Agreement or in the event that the Company or any
other person takes any action to declare the Agreement void or unenforceable, or
institutes any litigation designed to deny, or to recover from, the Executive
the benefits intended to be provided to the Executive hereunder, the Company
irrevocably authorizes the Executive from time to time to retain counsel of his
choice, at the expense of the Company as hereafter provided, to represent the
Executive in connection with the initiation or defense of any litigation or
other legal action, whether by or against the Company or any director, officer,
stockholder or other person affiliated with the Company, in any jurisdiction.
Notwithstanding any existing or prior attorney-client relationship between the
Company and such counsel, the Company irrevocably consents to the Executive
entering into an attorney-client relationship with such counsel, and in that
connection the Company and the Executive agree that a confidential relationship
shall exist between the Executive and such counsel. The Company shall pay and be
solely responsible for any and all reasonable attorneys' and related fees and
expenses incurred by the Executive as a result of the Company's failure to
perform this Agreement or any provision thereof or as a result of the Company or
any person contesting the validity or enforceability of this Agreement or any
provision thereof, up to $100,000 in the aggregate.

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     14. Rights and Remedies Cumulative. No right or remedy conferred upon or
reserved to the Executive is intended to be exclusive of any other right or
remedy, and every right and remedy shall, to the extent permitted by law, be
cumulative and in addition to every other right and remedy given hereunder or
now or hereafter existing at law or in equity or otherwise. The assertion or
employment of any right or remedy under this Agreement, or otherwise, shall not
prevent the concurrent assertion or employment of any other appropriate right or
remedy.

     IN WITNESS WHEREOF, the parties have executed this Agreement effective on
the date and year first above written.

                                       ADVANCED NEUROMODULATION SYSTEMS, INC.:

                                       By:  /s/ F. Robert Merrill
                                            ----------------------------------
                                            F. Robert Merrill
                                       Its: Executive Vice President and Chief
                                            Financial Officer

                                       EXECUTIVE:

                                       By: /s/ Christopher G. Chavez
                                           -----------------------------------
                                           Christopher G. Chavez