Exhibit 10.4
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                               SECURITY AGREEMENT
                                                                   MAY 3, 2001
                                                                   -----------
                                                                         DATE
                                Howard Silverman
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                                      NAME

A resident(s) of           6646 Indian School Rd. NE
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                                 NO. AND STREET

  Albuquerque                                                NM         87110
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      CITY                           COUNTY                      STATE

(Hereinafter called "DEBTOR"), for consideration grants to

                       TrueVision Medical Associates, Inc.
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                                      NAME
                                 P.O. Box 4834
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                                 NO. AND STREET
        San Diego                                            CA          92164
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      CITY                          COUNTY                        STATE

(Hereinafter called "SECURED PARTY") a security interest in the following
property and any and all additions, accessions and substitutions thereto or
therefore (hereinafter called the "COLLATERAL"):

See attached Exhibit A


If marked here,[ ] Debtor grants a security interest in all similar property
owned by Debtor during the time the Obligations are outstanding, although such
property may be acquired after the date hereof; provided, however, that no
security interest shall attach to consumer goods other than accessions unless
the Debtor acquires rights in them within ten (10) days after the Secured Party
gives value.

To secure payment of the indebtedness evidenced by A Certain promissory note
                                                  ---
      of even date herewith, payable to the Secured Party, or order, as follows:
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        1. $3,423.26 payable in June 1, 2001

        2. 3,423.26 on 1st of each and every month unti8l Promissory Note of
           $57,000.00 is paid in full.


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<PAGE>
Together with such additional sums as may hereafter be advanced to the Debtor or
expended by the Secured Party or its assigns on behalf of the Debtor or his
assigns for any purpose whatsoever and evidenced by notes, drafts, open account,
or otherwise, with interest thereon at rates to be fixed at the time of
advancing or expending such additional sums; provided, however that the making
of any such advances or expenditures shall be optional with Secured Party, or
its assigns; and this security agreement shall secure the payment of any and all
extensions or renewals and successive extensions or renewals of said note or
notes, and of any indebtedness at any time owing to Secured Party, or its
assigns, and shall further secure the payment of any and all indebtedness owing
by Debtor to Secured Party, and for all of which this security agreement shall
stand as continuing security until paid (all of such indebtedness being referred
to as the "Obligations"); and the Debtor agrees that the Secured Party, its
successors or assigns, may apply any payments made on the Obligations secured
hereby, at its option, on any of the notes or other indebtedness secured hereby.



DEBTOR EXPRESSLY WARRANTS AND COVENANTS:

    1. That except for the security interest granted hereby Debtor is, or to the
extent that this agreement states that the Collateral is to be acquired after
the date hereof, will be, the owner of the Collateral free from any adverse
lien, security interest or encumbrance; and that Debtor will defend the
Collateral against all claims and demands of all persons at any time claiming
the same or any interest therein.

    2. That is marked here , the Collateral is used or bought primarily for
personal, family or household purposes; that if marked here , the Collateral is
used or bought primarily for use in farming operations; that if marked here the
Collateral is being acquired with the proceeds of the note or notes, which
Secured Party may disburse direct to the Seller of the collateral.

    3.  That Debtor's count of residence is as stated above, and the Collateral
will be kept at

      1700 Louisiane Blvd. NE    Albuquerque     Bernalillo      New Mexico
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          NO. STREET                CITY           COUNTY          STATE

    4. That if any of the Collateral is crops growing or to be grown, goods
which are or are to become fixtures, timber to be cut or minerals or the like
(including oil and gas) or accounts financed at the wellhead or minehead of the
well or mine, a description of the real estate is as follows:



And the name of the record owner of the real estate is
                                                      -------------------------

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And that if the Collateral is attached to real estate or if the Collateral
includes crops growing or to be grown, goods which are or are to become


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<PAGE>
fixtures, timber to be cut or minerals or the like (including oil and gas) or
accounts financed at the wellhead or minehead or the well or mine, Debtor will,
on demand or Secured Party, furnish Secured Party with a disclaimer or
disclaimers or a subordination agreement signed by all persons having an
interest in the real estate, disclaiming or subordinating any interest in the
Collateral which is prior to Secured Party's interest.

    5. That no financing statement covering the Collateral or any proceeds
thereof is on file in any public office and that at the request of Secured
Party, Debtor will join with Secured Party in executing one or more financing
statements pursuant to the New Mexico Uniform Commercial Code in form
satisfactory to Secured Party and will pay the cost of filing such financing
statement, this security agreement and any continuation or termination
statement, in all public offices wherever filing is deemed by Secured Party to
be necessary or desirable.

    A carbon, photographic or other reproduction of a Security Agreement or a
Financing Statement is sufficient as a Financing Statement.

    6. Not to sell, transfer or dispose of the Collateral, nor take the same or
attempt to take the same from the county where dept as above stated, without
prior consent of the Secured Party.

    7.  To pay all taxes and assessments of every nature which may be levied or
assessed against the Collateral.

    8. Not to permit or allow any adverse lien, security interest or encumbrance
whatsoever upon the Collateral, and not to permit the same to be attached or
replevined.

    9. That the Collateral is in good condition, and that he will. At his own
expense, keep the same in good condition and from time to time, forthwith,
replace and repair all such parts of the collateral as may be broken, worn out,
or damaged without allowing any lien to be created upon the Collateral on
account of such replacement or repairs, and that the Secured Party may examine
and inspect the Collateral at any time, wherever located.

    10.At its option, Secured Party may discharge taxes, liens or security
interests or other encumbrances at any time levied or placed on the collateral
and may pay for the repair of any damage or injury and may pay for the
maintenance and preservation of the Collateral. Debtor agrees to reimburse
Secured Party on demand for any payment made or expense incurred by Secured
Party pursuant to the foregoing authorization. Until such reimbursement, the
amount of any such payment, with interest at the rate of 10% annum from date of
payment until reimbursement, shall be added to the indebtedness owed by Debtor
and shall be secured by this security agreement.

    11.That he will at his own expense forthwith insure the Collateral in a
reliable insurance company against loss or damage by fire and Extended coverage
For an amount equal to the aggregate sum of said indebtedness, and keep the same
so insured continuously until the full amount of said indebtedness is paid, with
loss payable to Secured Party as its interest may appear, and that he will on
demand deliver said policies of insurance or furnish proof of such insurance to


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<PAGE>
the Secured Party, and in case of loss, the Secured Party shall retain from the
insurance money an amount equal to the total balance of said indebtedness the
same is due or not. Should the Debtor fail or forthwith effect such insurance
and deliver the policies or furnish proof of such insurance as aforesaid, or
fail to keep the Collateral so insured continuously until the full amount to
said indebtedness is paid, the Secured Party may at its option effect such
insurance and the amount so paid for such insurance with interest at the rate of
10% per annum form date of payment until repaid shall be added to said
indebtedness, and the same shall be secured by this security agreement.

    12. That in the event this security agreement is placed in the hands of any
attorney for enforcement, said Debtor will pay the reasonable attorney's fees of
Secured Party, but in no event less than then per cent (10%) of the total amount
due or unpaid and said Debtor will pay said Secured Party any and all costs and
expenses incurred in recovering possession of the Collateral and incurred in
enforcing this security agreement, and the same shall be secured by this
security agreement.

    13. That he will not use the Collateral in violation of any applicable
statuses, regulations or ordinances, and that if the Collateral includes one or
more motor vehicles he will not rent the Collateral nor allow the Collateral to
be used in rental service, or in any speed or endurance contest.

    14. That if the Collateral includes one or more motor vehicles he will not
use or cause or permit the Collateral to be used for the transportation of
liquor, wines or any other beverage for personal or commercial use, prohibited
by any Federal or State statute to be transported.

    UNTIL DEFAULT debtor may have possession of the Collateral and use it in any
lawful manner not inconsistent with this agreement and not inconsistent with
this agreement and not inconsistent with any policy of insurance thereon, and
upon default Secured Party shall have the immediate right to the possession of
the Collateral.

    DEBTOR SHALL BE IN DEFAULT under this agreement upon the happening of any of
the following events or conditions:

    (a)  default in the payment or performance of any obligation, covenant or
         liability contained or referred to herein or in any note evidencing the
         same;

    (b)  any warranty, representation or statement made or furnished to Secured
         Party or on behalf of Debtor proves to be false in any material respect
         when made or furnished;

    (c)  any event which results in the acceleration of the maturity of the
         indebtedness of Debtor to others under any indenture, agreement or
         undertaking;

    (d)  loss, theft, damage, destruction, sale or encumbrance to or of any of
         the Collateral, or the making of any levy, seizure or attachment
         thereof or thereon;


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<PAGE>



    (e)  death, dissolution, termination of existence, insolvency, business
         failure, appointment of a receiver of any part of the property of,
         assignment for the benefit of creditors by, or the commencement of nay
         proceeding under any bankruptcy or insolvency laws by or against Debtor
         or any guarantor or surety for Debtor.

    UPON SUCH DEFAULT and at any time thereafter, or if it deems itself
insecure, Secured Party may declare all Obligations secured hereby immediately
due and payable and shall have the remedies of a secured party under the New
Mexico Uniform Commercial Code. Secured Party may require Debtor to assemble the
Collateral and deliver or make it available to Secured Party at a place to be
designated by Secured Party which is reasonably convenient to both parties.
Unless the Collateral is perishable or threatens to decline speedily in value or
is of a type customarily sold on a recognized market, Secured Party will give
Debtor reasonable notice of the time and place of any public sale thereof or of
the time after which any private sale or any other intended disposition thereof
is to be made. The requirements of reasonable notice shall be met if such notice
is mailed, postage prepaid, to the address of Debtor shown at the beginning of
this agreement at least five days before the time of the sale or disposition.
Expenses of retaking, holding, preparing for sale, selling or the like shall
include Second Party's reasonable attorney's fees and legal expenses.

    No waiver by Secured Party of any default shall operate as a waiver of any
other default or of the same default on a future occasion. The taking of this
security agreement shall not waive or impair any other security said Secured
Party may have or hereafter acquire for the payment of the above indebtedness,
nor shall the taking of any such additional security waive or impair this
security agreement; but said Secured Party may resort to any security it may
have in the order it may deem proper, and notwithstanding any collateral
security, Secured Party shall retain its rights of setoff against the Debtor.

    All rights of Secured Party hereunder shall inure to the benefit of its
successors and assigns; and all promises and duties of Debtor shall bind his
heirs, executors or administrators or his or its successors or assigns. If there
be more than one Debtor, their liabilities hereunder shall be joint and several.

    This agreement shall become effective when it is signed by Debtor.

Secured Party:                         Debtor:

/s/                                    /s/ Howard Silverman
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True Vision Medical Associates, Inc.      Howard Silverman
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    Note: Notarized acknowledgments are not required by New Mexico Statutes for
UCC financing statements and security agreements (New Mexico Statutes Annotated,
w/1985 Cumulative Supplements, Sec. 14-8-4).




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<PAGE>
<TABLE>
<S>                      <C>   <C>             <C>             <C>          <C>             <C>
Item                     Qty   Manufacturer    Model           Number       Serial          Lot Number
                                               Name                         Number
Pachymeter                 1   Sonomed         Micropach       200p         P2-0699-0449
Topographer                1   Zeis-Humphreys                  Ae992            992-2332
Autoclave                  1   SCICAN          Statum          2000            2109I6730
Autoclave                  1   SCICAN          Statum          2000              208887A
Autoclave                  1   Ritter          Speedclave                           678L
Autoclave                  1   Fisher                          750             D59983577
Plum Sled-base chairs      4   Hayworth                        C500-1213                     MKB122018
Plum Sled-base chairs      2   Hayworth                        C500-1213                     MKB122292
Plum Sled-base chairs      3   Hayworth
Chair                      1   Marco                           1280              99H0101
Stand                      1   Marco                           1290              99G0207
Phoropter                  1   Marco           Reichert        11635             17255-4
Slit Lamp                  1   Marco           Ultra Slitlamp                   99HJ0123
                                                      G2
Projector                  1   Marco                                               25839
Chair                      1   Marco                           1280              99H0102
Stand                      1   Marco                           1290             999G0208
Phoropter                  1   Reichert                        11635             17255-4
Slit Lamp                  1   Marco                                               25836
Projector                  1   Marco                                               25836
Side Chair                 1   Reliance                        4246          43109902110
Side Chair                 1   Reliance                        4246          43109902121
Side Chair                 1   Reliance                        4246           4310990216
Assorted Refractive Surgical Instruments
2 Black Leather/Wood
Recliner Chairs
2 Black Leather/Wood
Ottomans
3 Wood Office Desks
1 Wood Credenza
1 Toshiba Phone Systems & 9 Handsets
Computer Network: 1 Server & 3 Complete Work Stations
ACT Database
CompuLink Software
ALL PATIENT FILES
</TABLE>


EXHIBIT A
To Security agreement dated May 3, 2001
By and between Howard Silverman, Debtor and
TrueVision Medical Associates, Inc., Secured Party

/s/ Howard Silverman
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Howard Silverman

/s/ John C. Homan
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John C. Homan, President
TrueVision Medical Associates, Inc.,

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