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                                                                    EXHIBIT 10.2
                                    AMENDMENT

      THIS AMENDMENT is made as of the 31st day of July, 2003, between General
Electric Capital Corporation ("Secured Party") and ChromaVision Medical Systems,
Inc. ("Debtor") in connection with that certain Master Security Agreement, dated
as of July 15, 2003 ("Agreement"). The terms of this Amendment are hereby
incorporated into the Agreement as though fully set forth therein. Section
references below refer to the section numbers of the Agreement. The Agreement is
hereby amended as follows:

      2. REPRESENTATIONS, WARRANTIES AND COVENANTS OF DEBTOR.

      Subsection (m) is hereby added to and made a part of the Agreement and
      reads as follows:

      "(m) Debtor's Intellectual Property, as defined in Section 7 below, is and
      will remain free and clear of all liens, claims and encumbrances of any
      kind whatsoever, except for Permitted Liens as defined in subsection (k)
      of this Section."

      3. COLLATERAL.

      Subsection (a) is hereby replaced with the following:

      "(a) Except for the leasing, sale and placement of equipment to Debtor's
      customers in the Ordinary Course of Business and until the declaration of
      any default, Debtor shall remain in possession of the Collateral; except
      that Secured Party shall have the right to possess (i) any chattel paper
      or instrument that constitutes a part of the Collateral, and (ii) any
      other Collateral in which Secured Party's security interest may be
      perfected only by possession. Secured Party may inspect any of the
      Collateral during normal business hours after giving Debtor reasonable
      prior notice. If Secured Party asks, Debtor will promptly notify Secured
      Party in writing of the location of any Collateral. Ordinary Course of
      Business is defined as the Debtor's business of leasing certain
      proprietary medical devices for testing purposes to qualified third party
      users, such as pathology laboratories, hospitals, clinics, research
      facilities and companies involved in the discovery and development of
      therapeutic applications for diseases; the sale, from time to time, of
      individual units of inventory, whether new or coming off lease; and the
      sale or placement, from time to time, of inventory units, whether in whole
      or part, with research facilities and biotechnology companies considered
      key to promoting the benefits and reputation of the Debtor's products and
      intellectual property; except that such sales and placements shall not be
      of such extent as to materially erode Secured Party's overall collateral
      base."

      Subsection (c) is hereby replaced with the following:

      "(c) Except for the leasing, sale and placement of equipment to Debtor's
      customers in the Ordinary Course of Business, Secured Party does not
      authorize and Debtor agrees it shall not (i) part with possession of any
      of the Collateral (except to Secured Party or for maintenance and repair),
      (ii) remove any of the Collateral from the continental United States, or
      (iii) sell, rent, lease, mortgage, license, grant a security interest in
      or otherwise transfer or encumber (except for Permitted Liens) any of the
      Collateral."

      Subsection (g) is hereby added to and made a part of the Agreement and
      reads as follows:

      "(g) Debtor agrees to comply with Secured Party's request for collateral
      monitoring of customer contracts in addition to contract audits. Debtor
      agrees to pay to Secured Party the
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      collateral monitoring fees of $5,000. for year one, $5,000 for year two
      and $6,250. for year three with such payment made in advance at the
      appropriate anniversary date of the first funding. In addition, Debtor
      agrees to pay Secured Party an audit fee of $500. per person, per day for
      auditing of the Debtor's contracts, receivables, and inventory."

      5. REPORTS.

      Subsection (b) is hereby replaced with the following:

      "(b) Debtor will deliver to Secured Party financial statements and reports
      as follows.

      -     quarterly unaudited statements and annual audited statements,
            certified by a recognized firm of certified public accountants,
            within 15 days after the statements are provided to the Securities
            and Exchange Commission ("SEC"). All such statements are to be
            prepared using generally accepted accounting principles ("GAAP")
            and, if Debtor is a publicly held company, are to be in compliance
            with SEC requirements.

      -     Monthly aging of receivable balances, by in-service contract, within
            15 days of month end.

      -     Monthly report on location of ACIS and ACCESS units within 15 days
            of month end.

      -     Monthly listing of cancelled contracts by name, location and reason
            within 15 days of month end.

      All reports will be blanket certified on a monthly basis by Debtor's Chief
      Financial Officer."

      7. DEFAULT AND REMEDIES.

      Subsection (a) is hereby replaced with the following:

      "(a) Debtor shall be in default under this Agreement and each of the other
Debt Documents if:

      (i) Debtor breaches its obligation to pay when due any installment or
      other amount due or coming due under any of the Debt Documents and fails
      to cure the breach within ten (10) days;

      (ii) Except for the leasing, sale and placement of equipment to Debtor's
      customers in the Ordinary Course of Business, Debtor, without the prior
      written consent of Secured Party, attempts to or does sell, rent, lease,
      license, mortgage, grant a security interest in, or otherwise transfer or
      encumber (except for Permitted Liens) any of the Collateral;

      (iii) Debtor breaches any of its insurance obligations under Section 4,
      and fails to cure any breach within thirty (30) days after written
      notification of same from an insurer;

      (iv) Debtor breaches any of its other obligations under any of the Debt
      Documents and fails to cure that breach within thirty (30) days after
      written notice from Secured Party;

      (v) Any warranty, representation or statement made by Debtor in any of the
      Debt Documents or otherwise in connection with any of the Indebtedness
      shall be false or misleading in any material respect;

      (vi) Any of the Collateral is subjected to attachment, execution, levy,
      seizure or confiscation in any legal proceeding or otherwise, or if any
      legal or administrative proceeding is commenced against Debtor or any of
      the Collateral, which in the good faith judgment of
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      Secured Party subjects any of the Collateral to a material risk of
      attachment, execution, levy, seizure or confiscation and no bond is posted
      or protective order obtained to negate such risk;

      (vii) Debtor breaches or is in default under any other agreement between
      Debtor and Secured Party, and fails to cure the breach within thirty (30)
      days of its occurrence;

      (viii) Debtor dissolves, terminates its existence, becomes insolvent or
      ceases to do business as a going concern;


      (ix) A receiver is appointed for all or of any part of the property of
      Debtor, or Debtor makes any assignment for the benefit of creditors;

      (x) Debtor files a petition under any bankruptcy, insolvency or similar
      law, or any such petition is filed against Debtor and is not dismissed
      within forty-five (45) days;

      (xi) Debtor's improper filing of an amendment or termination statement
      relating to a filed financing statement describing the Collateral;

      (xii) Debtor defaults under any other material obligation for (A) borrowed
      money, (B) the deferred purchase price of property or (C) payments due
      under any lease agreement;

      (xiii) At any time during the term of this Agreement Debtor sells more
      than 50% of its interest in the company to another corporation or business
      or all or substantially all of its assets without Secured Party's prior
      written consent;

      (xiv) There is a material adverse change in the Debtor's financial
      condition;

      (xv) Debtor or other obligor for any of the Indebtedness sells, transfers,
      assigns, mortgages, pledges, leases, grants a security interest in or
      encumbers any or all of Debtor's Intellectual Property now existing or
      hereafter acquired. Intellectual Property shall consist of but not be
      limited to any and all owned or licensed patents, trademarks and
      copyrights. For purposes of this paragraph xv, licenses or sublicenses by
      the Debtor of its Intellectual Property as part of a research and
      development or similar arrangement shall be excluded. Debtor shall provide
      Lessor with a listing of licenses and sublicenses granted to third parties
      within fifteen (15) days of receipt of written request;

      (xvi) Debtor fails to comply with any of the financial covenants set forth
      in that certain Financial Covenants Addendum No. 1 to the Agreement; or

      (xvii) Debtor changes the terms of the lockbox agreement with Comerica
      Bank - California or moves the lockbox account without Secured Party's
      prior written consent, which consent will not be unreasonably withheld."

      Subsection (b) is hereby replaced with the following:

      "(b) If Debtor is in default, the Secured Party, at its option, may
      declare any or all of the Indebtedness to be immediately due and payable,
      without demand or notice to Debtor. The accelerated obligations and
      liabilities shall bear interest (both before and after any judgment) until
      paid in full at the lower of eighteen percent (18%) per annum or the
      maximum rate not prohibited by applicable law."
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      Subsection (h) is hereby added to and made a part of the Agreement and
      reads as follows:

      "(h) In the event a default has occurred under subsection (a)(xvi) above,
      Secured Party shall be entitled to receive the proceeds associated with a
      sale of the Intellectual Property up to the balance of the Indebtedness
      and prior to the payment of any other creditor or party."

      TERMS USED, BUT NOT OTHERWISE DEFINED HEREIN SHALL HAVE THE MEANINGS GIVEN
TO THEM IN THE AGREEMENT. EXCEPT AS EXPRESSLY AMENDED HEREBY, THE AGREEMENT
SHALL REMAIN IN FULL FORCE AND EFFECT. IF THERE IS ANY CONFLICT BETWEEN THE
PROVISIONS OF THE AGREEMENT AND THIS AMENDMENT, THEN THIS AMENDMENT SHALL
CONTROL.

      IN WITNESS WHEREOF, the parties hereto have executed this Amendment
simultaneously with the Agreement by signature of their respective authorized
representative set forth below.

GENERAL ELECTRIC CAPITAL CORPORATION          CHROMAVISION MEDICAL SYSTEMS, INC.

By: /s/ JOHN EDEL                             By: /s/ STEPHEN T.D. DIXON

Name: John Edel                               Name: Stephen T.D. Dixon

Title: SVP                                    Title: EVP and CFO