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                                                                   EXHIBIT 10.18

                            INDEMNIFICATION AGREEMENT

                          UROQUEST MEDICAL CORPORATION

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<S>   <C>             <C>                             <C>
1.    EFFECTIVE DATE: October 12, 1998

2.    PARTIES:        UroQuest Medical Corporation     Jeffrey L. Kaiser
                       173 Constitution Drive           c/o 173 Constitution Drive
                       Menlo Park, CA  94025            Menlo Park, CA  94025
                       (the "Company")                  (the "Indemnified Party")
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3.    RECITALS/AGREEMENT:


      (a) At the request of the "Company", the Indemnified Party currently
      serves as a director, officer or manager of the Company (as defined
      below), or in a combination of these positions. As such, Indemnified Party
      may be subjected to claims, suits or proceedings.

      (b) The Company's By-laws and Section 145 of the Delaware General
      Corporation Law contemplate that contracts may be made between the Company
      and members of its Board of Directors, officers and employees with respect
      to indemnification.

      (c) In consideration of Indemnified Party's acceptance and continuation of
      service as a director, officer or manager, or in a combination of these
      positions, after the date of this Agreement, and in consideration of the
      mutual covenants stated herein, the parties agree as follows.

4.    DEFINITIONS: As used in this Agreement, the following terms have the
      following meanings:

      (a) Change in Control. A "Change in Control" shall be deemed to have
      occurred if any of the following events occurs: (i) any "person" (as such
      term is used in Section 13(d) and 14(d) of the Securities Exchange Act of
      1934, as amended) becomes after the date hereof the "beneficial owner" (as
      defined in Rule 13d-3 under said Act), directly or indirectly, of
      securities of the Company representing 30% or more of the total number of
      votes that may be cast for the election of directors of the Company
      (called in this definition "voting securities"); (ii) at least 40% of the
      directors of the Company constitute persons who were not, at the time of
      their first election to the Board of Directors of the Company, candidates
      proposed by a majority of the Company's Board of Directors in office prior
      to the time of such first election; (iii) either stockholder approval of
      the dissolution of the Company or the actual dissolution of the Company;
      (iv) a sale or other disposition,




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      or the last sale or other disposition to occur in a series of sales and/or
      other dispositions within any 12-month period ("Serial Sales"), by the
      Company of assets which (at the time of the sale or disposition or, in the
      case of Serial Sales, as of the beginning of such 12-month period) account
      for more than 75% of the total assets or 40% of the revenues of the
      Company, as determined in accordance with generally accepted accounting
      principles; provided, however, that no sale or disposition of assets or
      stock shall be taken into account to the extent that the proceeds of such
      sale or disposition (whether in cash or in-kind) are reinvested in the
      Company or are, in the case of proceeds received in-kind, used in the
      ongoing conduct of the Company, provided further that such a reinvestment
      shall not be deemed to have occurred unless made within 12 months of such
      sale or disposition and provided further that, the term reinvestment shall
      include, among other things, the use of proceeds to repay debt incurred in
      connection with the operation of the business in which the assets sold or
      disposed of were used; (v) the stockholders shall approve any merger,
      consolidation, or like business combination or reorganization of the
      Company, the consummation of which would result in the voting securities
      of the Company outstanding immediately prior thereto representing (by
      remaining outstanding or being converted into securities of the surviving
      entity or otherwise) less than 70% of the voting securities of the Company
      or such surviving entity outstanding immediately after such merger,
      consolidation, business combination or reorganization; or (vi) any other
      event which the Company's Board of Directors determines, in its
      discretion, would materially alter the structure of the Company or its
      ownership.

      (b) Corporation Law. The term "Corporation Law" means the Delaware General
      Corporation Law as it exists on the date of this Agreement and as it may
      be hereafter amended from time to time. In the case of any amendment of
      the Delaware General Corporation Law after the date of this Agreement,
      when used in reference to an act or omission occurring prior to
      effectiveness of such amendment (unless prohibited by law), the term
      "Corporation Law" shall include such amendment only to the extent that the
      amendment permits the Company to provide broader indemnification rights
      than the Delaware General Corporation Law permitted the Company to provide
      prior to the amendment.

      (c) Director, Officer or Manager. As used in reference to a position held
      by Indemnified Party, the term "director," "officer" or "manager" means a
      director officer or manager (as designated by the person's title in the
      case of a manager) of the Company and, while a director, officer or
      manager of the Company, Indemnified Party's serving at the Company's
      request as a director, officer, manager, partner, trustee, employee, agent
      or fiduciary of any corporation, partnership, joint venture, trust, other
      enterprise or employee benefit plan (including without limitation any
      service as a director, officer, manager, employee, agent or fiduciary
      which imposes duties on, or involves services by, such director, officer,
      manager, employee or agent with respect to any employee benefit plan, its
      participants or beneficiaries). The terms "director," "officer" and
      "manager" also include, unless the context otherwise requires, the estate
      or personal representative of a director, officer or manager. The terms
      "director" and "officer" shall also include any such broader definition as
      may be provided in the Corporation Law with amendments after the date of
      this Agreement.



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      (d) Potential Change in Control. A "Potential Change in Control" shall be
      deemed to have occurred if (i) the Company enters into an agreement, the
      consummation of which would result in the occurrence of a Change in
      Control (ii) any person or entity (including the Company) publicly
      announces an intention to take or to consider taking actions which, if
      consummated, would constitute a Change in Control or (iii) the Board of
      Directors adopts a resolution to the effect that, for purposes of this
      Agreement, a potential Change in Control has occurred.

      (e) Proceeding. The term "proceeding" means any threatened, pending or
      completed action, suit or proceeding, or any inquiry or investigation,
      whether civil criminal, administrative or investigative, and whether
      formal or informal.

      (f) Reviewing Party. "Reviewing Party" means the person or body determined
      in accordance with Section 9.

5. AGREEMENT TO INDEMNIFY: The Company shall indemnify, and keep indemnified,
Indemnified Party in accordance with, and to the full extent permitted and/or
required by, the Corporation Law and any other applicable law from and against
any expenses (including but not limited to attorneys' fees, expenses of
investigation and preparation, and fees and disbursements of Indemnified Party's
accountants or other experts), judgments, fines (including but not limited to
excise taxes assessed on a person with respect to an employee benefit plan),
penalties and amounts paid in settlement (including without limitation all
interest, assessments and other charges paid or payable in connection with any
of the foregoing) actually and reasonably incurred by Indemnified Party in
connection with any proceeding in which Indemnified Party was or is made a party
or was or is involved (for example, as a witness) by reason of the fact that
Indemnified Party is or was a director, officer or manager of the Company.

6. D&O INSURANCE: So long as Indemnified Party may be subject to any possible
proceeding by reason of the fact that Indemnified Party is or was a director or
officer of the Company, to the extent the Company maintains an insurance policy
or policies providing directors' and officers' liability insurance, Indemnified
Party shall be covered by such policy or policies, in accordance with its or
their terms, to the maximum extent of the coverage applicable to any then
current director or officer of the Company.

7. ADVANCES: In the event of any proceeding in which Indemnified Party is a
party or is involved and which may give rise to a right of indemnification from
the Company pursuant to this Agreement, following written request to the Company
by Indemnified Party, the Company shall pay to Indemnified Party, in accordance
with and to the full extent permitted and/or required by the Corporation Law,
amounts to cover reasonable expenses incurred by Indemnified Party in such
proceeding in advance of its final disposition upon receipt of (a) a written
undertaking executed by or on behalf of Indemnified Party to repay the advance
if it shall ultimately be determined that Indemnified Party is not entitled to
be indemnified by the Company and (b) satisfactory evidence as to the amount of
such expenses.

8. BURDEN OF PROOF: If under applicable law, the entitlement of Indemnified
Party to be indemnified or advanced expenses hereunder depends upon whether a




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standard of conduct has been met, the burden of proof of establishing that
Indemnified Party did not act in accordance with such standard shall rest with
the Company. Indemnified Party shall be presumed to have acted in accordance
with such standard and to be entitled to indemnification or the advancement of
expenses (as the case may be) unless, based upon a preponderance of the
evidence, it shall be determined that Indemnified Party has not met such
standard. For purposes of this Agreement, unless otherwise expressly stated, the
termination of any proceeding by judgment, order, settlement (whether with or
without court approval), conviction, or upon a plea of nolo contendere or its
equivalent, shall not create a presumption that Indemnified Party did not meet
any particular standard of conduct or have any particular belief.

9. DETERMINATION REGARDING STANDARD OF CONDUCT; REVIEWING PARTY: Any
determination as to whether Indemnified Party has met an applicable standard of
conduct for indemnification or advancement of expenses and any evaluation as to
the reasonableness of amounts claimed by Indemnified Party shall be made by the
Reviewing Party. If there has not been a Change of Control after the date of
this Agreement, the Reviewing Party shall be the Board of Directors of the
Company or such other body or persons appointed by the Board of Directors of the
Company as permitted by the Corporation Law. If there has been a Change of
Control after the date of this Agreement and if so requested by the Indemnified
Party, the Reviewing Party shall be an independent counsel who is selected by
the Indemnified Party and approved by the Company (which approval shall not be
unreasonably withheld). For this purpose, "independent counsel" means a law firm
or a member of a law firm that neither is at the time, nor in the past five
years has been, retained to represent (i) the Company or the Indemnified Party
in any matter material to either such party or (ii) any other party to the
Proceeding giving rise to a claim for indemnification under this Agreement.
Notwithstanding the foregoing, the term "independent counsel" shall not include
any person who, under the applicable standards of professional conduct then
prevailing under the law of the State of Delaware, would have a conflict of
interest in representing either the Company or the Indemnified Party in an
action to determine the Indemnified Party's rights under this Agreement. The
Company agrees to pay the reasonable fees of the independent counsel referenced
above and to indemnify fully such independent counsel against any and all
expenses (including without limitation attorneys' fees), liabilities, losses and
damages arising out of or relating to this Agreement or its engagement pursuant
to this Agreement.

10. NOTICE TO THE COMPANY: Indemnified Party shall notify the Secretary of the
Company in writing of any matter for which Indemnified Party intends to seek
indemnification hereunder as soon as reasonably practicable following the
receipt by Indemnified Party of written notice thereof; provided, however, that
delay in so notifying the Company shall not constitute a waiver or release by
Indemnified Party of rights hereunder.

11. COUNSEL FOR PROCEEDING; SETTLEMENTS: In the event of any proceeding in which
Indemnified Party is a party or is involved and which may give rise to a right
of indemnification hereunder, the Company shall have the right to retain counsel
satisfactory to Indemnified Party in his or her discretion, to represent
Indemnified Party and any others the Company may designate in such proceeding.
In any such proceeding, Indemnified Party shall have the right to retain
Indemnified Party's own 




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counsel but the fees and expenses of such counsel shall be at the expense of
Indemnified Party unless (a) the retention of such counsel has been specifically
authorized by the Company; (b) representation of Indemnified Party and another
party by the same counsel would be inappropriate, in the reasonable judgment of
Indemnified Party, due to actual or potential differing interests between them;
(c) the counsel retained by the Company and satisfactory to Indemnified Party
has advised Indemnified Party, in writing, that such counsel's representation of
Indemnified Party would be likely to involve such counsel in representing
differing interests which could adversely affect either the judgment or loyalty
of such counsel to Indemnified Party, whether it be a conflicting, inconsistent,
diverse or other interest; or (d) the Company shall fail to retain counsel for
Indemnified Party in such proceeding. Notwithstanding the foregoing, if an
insurance carrier has supplied directors' and officers' liability insurance
covering a proceeding and is entitled to retain counsel for the defense of such
proceeding, then the insurance carrier shall retain counsel to conduct the
defense of such proceeding unless Indemnified Party and the Company concur in
writing that the insurance carrier's doing so is undesirable. The Company shall
not be liable under this Agreement for any settlement of any proceeding effected
without its written consent. The Company shall not settle any proceeding in any
manner which would impose any penalty or limitation on Indemnified Party without
Indemnified Party's written consent. Consent to a proposed settlement of any
proceeding shall not be unreasonably withheld by either the Company or
Indemnified Party.

12. ENFORCEMENT; ACTION TO DETERMINE COMPLIANCE WITH STANDARD OF CONDUCT: The
Company acknowledges that Indemnified Party is relying upon this agreement in
serving as a director, officer or manager of the Company. If a claim for
indemnification or advancement of expenses is not paid in full by the Company
within sixty days, or within twenty days in the case of a claim for advancement
of expenses, after a written claim has been received from Indemnified Party by
the Company, Indemnified Party may at any time bring a legal action against the
Company to recover the unpaid amount of the claim. Indemnified Party shall also
be entitled to be paid by the Company all reasonable fees and expenses
(including without limitation fees of counsel) in bringing and prosecuting such
claim, unless as a part of the legal action concerning such claim the court
having jurisdiction over the action determines that each of the material
assertions made by Indemnified Party as a basis for the action was not made in
good filth or was frivolous. Neither the failure of the Reviewing Party or the
Company (including its Board of Directors, independent counsel or its
stockholders) to have made a determination prior to the commencement of such
action that indemnification of the Indemnified Party is proper in the
circumstances nor an actual determination by the Reviewing Party or the Company
(including its Board of Directors, independent legal counsel, or its
stockholders) that the Indemnified Party is not entitled to indemnification
shall be a defense to the action, be admissible as evidence, or create a
presumption that the Indemnified Party is not so entitled. Any such action shall
be de novo, and the Indemnified Party shall not be prejudiced by reason of any
such adverse determination. If an action is brought pursuant to this Section, a
final nonappealable order in such action shall constitute the ultimate
determination of the Indemnified Party's right to indemnification. Whether or
not Indemnified Party has met any applicable standard of conduct, the Court in
such suit may order indemnification or the advancement of expenses as the Court
deems proper (subject to any express limitation of the Corporation Law).
Further, the Company shall indemnify Indemnified Party from 




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and against any and all expenses (including without limitation attorneys' fees)
and, if requested by Indemnified Party, shall (within twenty days of such
request) advance such expenses to Indemnified Party, which are incurred by
Indemnified Party in connection with any claim asserted against or legal action
brought by Indemnified Party for recovery under any directors' and officers'
liability insurance policies maintained by the Company, regardless of whether
Indemnified Party is unsuccessful in whole or in part in such claim or suit.

13. PROCEEDINGS BY INDEMNIFIED PARTY: Notwithstanding other provisions of this
Agreement to the contrary, prior to a Change in Control the Company shall not
indemnify Indemnified Party and advance expenses to Indemnified Party in
connection with any proceeding (or part thereof) initiated by Indemnified Party
against the Company or any director, officer or manager of the Company unless
such proceeding (or part thereof) was authorized by the Board of Directors of
the Company.

14. ESTABLISHMENT OF TRUST: In the event of a Potential Change in Control the
Company shall, upon written request by Indemnified Party, create a trust for the
benefit of Indemnified Party (and possibly others as described below) and from
time to time upon written request of Indemnified Party shall fund such trust in
an amount sufficient to satisfy any and all expenses and other amounts for which
indemnification may be sought under this Agreement and which at the time of each
such request are reasonably anticipated to be incurred, are proposed to be paid
by Indemnified Party, have actually been paid by Indemnified Party or have
actually been claimed in a proceeding. The amount or amounts to be deposited in
the trust pursuant to the foregoing funding obligation shall be determined by
mutual agreement of the Company and Indemnified Party or, if they are unable to
reach such mutual agreement within ten days after any such request by
Indemnified Party for funding, by a Reviewing Party who is selected in
accordance with Section 9 of this Agreement as if a Change of Control had
occurred. In determining any such amounts, the parties or the Reviewing Party
(as the case may be) shall take into account the availability of any amounts
under any directors' and officers' liability insurance. At the Company's
discretion, the trust created by the Company at the request of the Indemnified
Party pursuant to the foregoing obligation may also be for the benefit of other
existing or former officers, directors or employees of the Company with respect
to indemnification and advancement of expenses, and may be a trust previously
created and existing at the time for the benefit of any such persons. If and to
the extent authorized by the parties or Reviewing Party, as the case may be,
when determining the amounts to be deposited in the trust; the trust may
commingle and combine into one or more funds amounts held for Indemnified Person
and such other persons. The terms of the trust shall provide that upon a Change
in Control (i) the trust shall not be revoked or the principal thereof invaded,
without the written consent of Indemnified Party, (ii) the trustee shall advance
within twenty days of a request by Indemnified Party, any and all expenses to
Indemnified Party (and Indemnified Party hereby agrees to reimburse the trust
under the circumstances under which Indemnified Party would be required to
reimburse the Company under Section 7 of this Agreement), (iii) the trust shall
continue to be funded by the Company in accordance with the funding obligation
set forth above, (iv) the trustee shall pay promptly (but in any event within
sixty days after a written claim for indemnification) to Indemnified Party all
amounts for which the Indemnified Party is entitled to indemnification pursuant
to this Agreement; and (v) all unexpended funds in such trust 




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shall revert to the Company upon a final determination by the Reviewing Party or
a court of competent jurisdiction, as the case may be, that Indemnified Party
has been fully indemnified under the terms of this Agreement. The trustee shall
be an individual or entity chosen by Indemnified Party and approved by the
Company (whose approval shall not be unreasonably withheld). All income earned
on the assets held in the trust shall be reported as income by the Company for
federal, state, local and foreign tax purposes. The Company shall pay all costs
of establishing and maintaining the trust and shall indemnify the trustee
against any and all expenses (including without limitation attorneys' fees),
liabilities, losses and damages arising out of or relating to this Agreement or
the establishment and maintenance of the trust. Nothing in this Section 14 shall
relieve the Company of any of its obligations under this Agreement.

15. NONEXCLUSIVITY: The rights of Indemnified Party for indemnification and
advancement of expenses under this Agreement shall not be deemed exclusive of or
in limitation of any rights to which Indemnified Party may be entitled under
Delaware law, the Company's Certificate of Incorporation or By-laws, vote of
shareholders or otherwise.

16. MISCELLANEOUS:

    (a) Effectiveness. This Agreement is effective for, and shall apply to, (i)
    any claim which is asserted or threatened before, on or after the date of
    this Agreement but for which no action, suit or proceeding has actually been
    brought prior to the date of this Agreement and (ii) any action, suit or
    proceeding which is threatened before, on or after the date of this
    Agreement but which is not pending prior to the date of this Agreement.
    Thus, this Agreement shall not apply to any action, suit or proceeding which
    has actually been brought before the date of this Agreement. So long as the
    foregoing standard of effectiveness has been satisfied, this Agreement shall
    be effective for and shall be applied to acts or omissions prior to, on or
    after the date of this Agreement.

    (b) Survival; Continuation. The rights of Indemnified Party hereunder shall
    inure to the benefit of the Indemnified Party (even after Indemnified Party
    ceases to be a director, officer or manager), Indemnified Party's personal
    representative, heirs, executors, administrators and beneficiaries; and this
    Agreement shall be binding upon the Company, its successors and assigns. The
    rights of Indemnified Party under this Agreement shall continue so long as
    Indemnified Party may be subject to any possible proceeding because of the
    fact that Indemnified Party was a director, officer or manager of the
    Company. If the Company sells, leases, exchanges or otherwise disposes of in
    a single transaction or series of related transactions, all or substantially
    all of its property and assets, the Company shall, as a condition precedent
    to such transaction, cause effective provision to be made so that the person
    or entity acquiring such property and assets shall become bound by and
    replace the Company under this Agreement.

    (c) Partial Indemnification. If the Indemnified Party is entitled to
    indemnification by the Company for some or a portion of expenses, judgments,
    fines or settlement amounts actually incurred by the Indemnified Party in a
    proceeding but not, however, for the total amount thereof the Company shall
    nevertheless indemnify 



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      the Indemnified Party for the portion of such expenses, judgments, fines
      or settlement amounts to which the Indemnified Party is entitled.

      (d) No Duplication of Payments. The Company shall not be liable under this
      Agreement to make any payment in connection with any proceeding against
      the Indemnified Party to the extent the Indemnified Party has otherwise
      actually received payment (under any insurance policy, bylaw or otherwise)
      of the amounts otherwise subject to indemnification under this Agreement.
      Governing Law. This Agreement shall be governed by the laws of the State
      of Delaware, without regard to the conflict of laws principles thereof.

      (e) Governing Law. This Agreement shall be governed by the laws of the
      State of Delaware, without regard to the conflict of the laws principles
      thereof.

      (f) Severability. If any provision of this Agreement shall be held to be
      prohibited by or invalid under applicable law, such provision shall be
      deemed amended to accomplish the objectives of the provision as originally
      written to the full extent permitted by law and all other provisions shall
      remain in full force and effect.

      (g) Amendment. No amendment, termination or cancellation of this Agreement
      shall be effective unless in writing signed by the Company and Indemnified
      Party.

      (h) Subrogation. In the event of payment under this Agreement the Company
      shall be subrogated shall execute all papers required and shall do
      everything that may be necessary to secure such rights, including the
      execution of such documents necessary to enable the Company effectively to
      bring suit to enforce such rights.

      (i) Headings. The headings in this Agreement are for convenience only and
      are not to be considered in construing this Agreement.

      (j) Counterparts. This Agreement may be executed in counterparts, both of
      which shall be deemed an original, and together shall constitute one
      document.

      The parties have executed this Agreement as of the Effective Date first
      above stated.


UROQUEST MEDICAL CORPORATION           Indemnified Party


By: /s/ Terry E. Spraker               /s/ Jeffrey L. Kaiser    
    -------------------------------    -----------------------------------------
                                           Jeffrey L. Kaiser

Title:  President and CEO
      -----------------------------