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                                                                  EXHIBIT 10.15


                    NOTE AND MORTGAGE MODIFICATION AGREEMENT
                          AND NOTICE OF FUTURE ADVANCE


        THIS NOTE AND MORTGAGE MODIFICATION AGREEMENT AND NOTICE OF FUTURE
ADVANCE (hereinafter "Agreement") dated as of the 30 this day of May, 2001, by
and between INVIVO RESEARCH, INC., an Oklahoma corporation (hereinafter the
"Mortgagor") and SUNTRUST BANK, a bank organized under the laws of the State of
Georgia (hereinafter the "Mortgagee").

                              W I T N E S S E T H:


        WHEREAS, Mortgagor executed and delivered unto First Union National Bank
of Florida ("First Union") that certain real estate balloon promissory note
dated October 8 1992, in the original principal amount of Eight Hundred Sixty
Two Thousand Five Hundred and No/100 Dollars ($862,500.00) (hereinafter the
"Note"), which Note is secured by that certain mortgage dated October 8, 1992,
and recorded October 12, 1992, in Official Records Book 4472, Page 4201, Public
Records of Orange County, Florida (as modified, the "Mortgage") for the purpose
of creating a lien on the real property more particularly described therein
(hereinafter referred to as "Property").

        WHEREAS, the Mortgage secured payment of the Note and certain other
obligations more particularly described in the Mortgage; and

        WHEREAS, on October 8, 1992, Mortgagor also executed and delivered to
First Union an Assignment of Leases and Rentals recorded October 12, 1992 in
Official Records Book 4472, Page 4226 (the "First Assignment") and a Uniform
Commercial Code Financing Statement recorded October 12, 1992 in Official
Records Book 4472, Page 4241, Public Records of Orange County, Florida; and

        WHEREAS, on January 21, 1993 Mortgagor executed that certain
Modification of Note and Mortgage recorded March 12, 1993, in Official Records
Book 4535, Page 2586, Public Records of Orange County, Florida; and

        WHEREAS, on July 31, 1996 Mortgagor executed that certain Notice of
Future Advance, Mortgage Modification and Spreading Agreement recorded August 1,
1996 in Official Records Book 5098, Page 3941, Public Records of Orange County,
Florida; and

        WHEREAS, on July 31, 1996 Mortgagor also executed that certain
Collateral Assignment of Leases, Rents and Profits recorded August 1, 1996 in
Official Records Book 5098, Page 3946 (the "Second Assignment"), and a UCC-1
Financing Statement recorded August 1, 1996 in Official Records Book 5098, Page
3950, Public Records of Orange County, Florida (the "Financing Statement"); and

        WHEREAS, on even date herewith, First Union has assigned the Note, the
Mortgage, the First and Second Assignments, the Financing Statement and certain
other loan documents to Mortgagee pursuant to that that certain Assignment of
Mortgage and Loan Documents recorded on even date immediately prior hereto; and

        WHEREAS, Mortgagor has requested the Mortgagee to make an additional
advance in the principal amount of Four Hundred Twenty Thousand Five Hundred
Eighty Seven and 31/100 ($420,587.31) and to amend the terms of the Note and
Mortgage, and the parties have agreed to modify the terms thereof in the manner
hereinafter appearing; and

        WHEREAS, Paragraph 1.17 of the Mortgage provides, among other things,
that the Mortgagee may, pursuant to the provisions of said paragraph, make
future and further advances from time to time, but that such secured
indebtedness shall not exceed at any time the maximum principal amount of two
times the amount of the Note, plus interest thereon, and any disbursements made
for the payment of taxes, levies, or insurance, on the Property, with interest
on such disbursements.



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        NOW, THEREFORE, in consideration of the covenants contained herein and
other good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged by the parties, the Mortgagor and Mortgagee agree as
follows:

        1. Recitals. The above recitals are true and correct, are incorporated
herein by reference and are made a part hereof for all purposes.

        2. Validity of Documents. The Mortgage, the First Assignment, the Second
Assignment and the Financing Statement (hereinafter referred to as the "Security
Instruments"), the Note and the other loan documents, as amended on even date,
are valid, in full force, and of full legal effect and are enforceable in
accordance with their terms. There are no defenses, counterclaims, offsets,
demands or claims which the Mortgagor has in connection with either the loan or
the loan documents which could be asserted to reduce or eliminate all or any
part of Mortgagor's obligations under the loan documents or which could be
asserted to mitigate or excuse Mortgagor's defaults in payment or performance of
the obligations, or if any, such defenses or offsets are hereby waived and
released by Mortgagor.

        3. Releases. Effective on even date, Mortgagor hereby releases, acquits
and forever discharges First Union, Mortgagee and their parents, subsidiaries,
affiliates, directors, officers, employees, attorneys, agents, servants and
representatives as well as the respective heirs, personal representatives,
successors and assigns or any and all of them (collectively "the Released
Mortgagee Parties") from any and all claims, counterclaims, demands, debts,
actions, causes of action, suits, contracts, indebtedness, agreements,
obligations, accounts, defenses, offsets against the indebtedness and
liabilities of any kind or character whatsoever, known or unknown, suspected or
unsuspected, in contract or in tort, in law or in equity, including without
limitation, such claims and defenses as fraud, mistake, duress,
misrepresentation, breach of contract, negligence, breach of duty, tortious
interference with advantageous relationships and usury which the Mortgagor ever
had, now have or hereafter might have against the Released Mortgagee Parties,
jointly or severally, for or by reason of any matter, cause or thing whatsoever
occurring up to the date of execution hereof, which relates to, in whole or in
part, directly or indirectly: (a) the loan; (b) the loan documents; (c) the
obligations; (d) the collateral; or (e) the administration of the loan. In
addition, the Mortgagor agrees not to commence, join in, prosecute or
participate in any suit or other proceeding in a position which is adverse to
any of the Released Mortgagee Parties arising directly or indirectly from any of
the foregoing matters.

        4. Current Balance. The unpaid principal balance of the Note on the date
hereof is One Million Two Hundred Seventy Nine Thousand Four Hundred Twelve and
69/100 and Dollars ($1,279,412.69), and interest is paid through May 31, 2001.

        5. Maturity Date. The maturity date of the Note and the Mortgage are
hereby extended until June 1, 2016 (the "Maturity Date").

        6. Additional Advance. In order to evidence the further advances
contemplated hereby, Mortgagor has executed and delivered to Mortgagee a Future
Advance Mortgage Note ("New Note") in the amount of Four Hundred Twenty Thousand
Five Hundred Eighty Seven and 31/100 ($420,587.31), of even date herewith. The
New Note shall be secured by the Mortgage to the same extent as if New Note had
been executed and delivered by Mortgagor to Mortgagee on the date of the
Mortgage.

        7. Consolidation. The Note and the New Note are hereby merged and
consolidated into one loan in the amount of One Million Seven Hundred Thousand
and No/100 Dollars ($1,700,000.00) (the "Consolidated Debt"), and are likewise
merged and consolidated into one instrument (the "Consolidation Mortgage Note")
with the terms and conditions of the Consolidation Mortgage Note prevailing.

        8. Modification of the Security Instruments. The Security Instruments
are hereby modified and amended to secure and encumber the Consolidated Debt,
and in the event of any default in payment of principal or interest under the
Consolidation Mortgage Note or in the event of any other default as set forth in
the Security Instruments, the Mortgagee shall have the same right to proceed
against the property encumbered and secured by the Security Instruments as if
the Security Instruments had initially secured the Consolidated Debt.

        9. Financial Statements. Mortgagor shall deliver the following items to
Mortgagee annually within 90 days after the end of Mortgagor's fiscal year or
business calendar or periodically as directed by Mortgagee: Federal Income Tax
Returns and complete and current copies of financial statements of Mortgagor,
including but not limited to an Income Statement, Balance Sheet and Schedule of
Rents covering the operation of the Mortgaged Property. In addition Mortgagor
shall deliver or cause to be delivered to Mortgagee: (i) quarterly financial
statements, (ii) quarterly and annual financial statements of Invivo Corporation
("Guarantor");


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and (iii) such other information, reports or statements as Mortgagee may request
in order to assess the current financial condition of Mortgagor and the
Guarantor.

        10. Debt Service Coverage. Mortgagor's debt service coverage ratio must
remain at or above 1.25 to 1 during the term of this loan. For purposes hereof,
debt service coverage shall be defined as earnings before interest, taxes,
depreciation and amortization divided by the sum of (i) current maturities of
long-term debt plus (ii) interest expense. This ratio shall be calculated
annually based on Mortgagor's June 30 fiscal year end financial statements and
shall be done on a trailing twelve month basis.

        11. Minimum Tangible Net Worth. Mortgagor shall maintain a tangible net
worth of at least $8,700,000.00 during the term of this loan. For purposes
hereof, Tangible Net Worth shall be defined as total assets less intangible
assets and total liabilities. Intangible assets include nonmaterial benefits
such as goodwill, patents, copyrights and trademarks. This covenant shall be
tested annually based on Mortgagor's June 30 fiscal year end financial
statements.

        12. Debt to Tangible Net Worth. Mortgagor shall maintain a maximum debt
to tangible net worth ratio of 2.0 to 1 during the term of this loan. This
covenant shall be tested annually based on Mortgagor's June 30 fiscal year end
financial statements.

        13. Status and Priority of Security Instruments. All of the property
encumbered by the Security Instruments on the date hereof shall continue in all
respects to be subject to the lien, charge and encumbrance of the Security
Instruments. Nothing contained herein or done hereby shall affect the lien,
charge or encumbrance of the above-mentioned documents or the priority thereof,
over other liens, charges, encumbrances or conveyances. Nothing contained herein
shall invalidate, impair or release any covenants, conditions, agreements or
stipulations contained therein and the documents shall continue in full force
and effect.

        14. Hazardous Wastes. The Mortgagor expressly represents to the
Mortgagee that, to the best of its knowledge the Property and the improvements
thereon have not in the past been used, and are not presently being used, and
will not in the future be used for the manufacture, handling, storage,
transportation, or disposal of hazardous or toxic materials. The Mortgagor
agrees to indemnify, defend, and hold the Mortgagee harmless from and against
any loss to the Mortgagee as a result of such past, present or future use,
manufacture, handling, storage, transportation or disposal of hazardous or toxic
materials. The Mortgagee, at the Mortgagee's sole option, may obtain at the
Mortgagor's expense a report from a reputable environmental consultant of the
Mortgagee's choice as to whether the Property and the improvements have been or
are presently being used for the manufacture, handling, storage, transportation,
or disposal of hazardous or toxic materials. If the report indicates such past
or present use, manufacturing, handling, storage, transportation or disposal,
the Mortgagee may require that all violations of law with respect to hazardous
or toxic materials be corrected and/or that the Mortgagor obtain all necessary
environmental permits before the Mortgagee shall fund any advance under this
Mortgage.

        15. Change in Ownership/Sale of Assets. During the term of this
Mortgage, there shall be no transfer of title without the prior written consent
of Mortgagee. Mortgagor shall not transfer, sell, assign, pledge, encumber or
otherwise dispose of any of Mortgagor's assets so as to materially adversely
affect Mortgagor's financial condition, without the prior written consent of
Mortgagee, in the Mortgagee's sole discretion. Furthermore, no shares or other
ownership or equity interest in Mortgagor may be sold, assigned, transferred,
pledged, encumbered or otherwise disposed of without the prior written consent
of Mortgagee.

        16. Default. Any default under the terms and conditions of this
Agreement or of any instrument set forth herein or contemplated hereby shall be
and is a default under every other instrument set forth herein or contemplated
hereby.

        17. Other Provisions. Except as set forth in this Agreement, all other
terms, conditions, and obligations set forth in the Note, the Mortgage and the
other Security Instruments shall remain in full force and effect and shall be
fully complied with.

        18. Severability. Whenever possible, each provision of this Agreement
shall be interpreted in such a manner as to be effective and valid under
applicable law, but if any provisions hereof shall be prohibited or invalid
under applicable law, such provision shall be ineffective to the extent of such
prohibition or invalidity only, without invalidating the remainder of such
provision or of the remaining provisions of this Agreement.

        19. Headings. The headings of the paragraphs contained in this Agreement
are for convenience of reference only and do not form a part hereof and in no
way modify, interpret or construe the meaning of the parties hereto.



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        20. Governing Law. All questions with respect to the construction of
this Agreement, and the rights and liabilities of the parties to this Agreement,
shall be governed by the laws of the State of Florida.

        21. Parties Bound. This Agreement shall inure to the benefit of, and
shall be binding on, the assigns, successors in interest, personal
representatives, estates, heirs, and legatees of each of the parties to this
Agreement.

        22. Entire Agreement; Modifications. This Agreement contains the entire
agreement of the parties and supersedes any prior written or oral agreements
among them concerning the subject matter of this Agreement. There are no
representations, agreements, arrangements, or understandings, oral or written,
between and among the parties relating to the subject matter contained in this
Agreement that are not fully expressed in this Agreement. This Agreement may
only be modified in writing.

        23. WAIVER OF JURY TRIAL. ALL PARTIES TO THIS AGREEMENT, WHETHER
MORTGAGOR OR MORTGAGEE, HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY, AFTER
CAREFUL CONSIDERATION AND AN OPPORTUNITY TO SEEK LEGAL ADVISE, WAIVE THEIR
RIGHTS TO HAVE A TRIAL BY JURY IN RESPECT TO ANY LITIGATION ARISING OUT OF OR IN
ANY WAY CONNECTED WITH ANY OF THE PROVISIONS OF THE NOTE, THE MORTGAGE, THE
INSTRUMENTS OF SECURITY OR ANY OTHER DOCUMENTS EXECUTED IN CONJUNCTION WITH THE
LOAN SECURED BY THE MORTGAGE DATED OCTOBER 8, 1992 OR ANY MODIFICATIONS OR
EXTENSIONS THEREOF.

        IN WITNESS WHEREOF, the Mortgagor has caused this Agreement to be duly
executed as of the date first set forth above.



Signed and sealed
in the presence of:                       "MORTGAGOR"

                                          INVIVO RESEARCH, INC.,
                                          an Oklahoma corporation



---------------------------                By:
Name:                                          --------------------------------
     ----------------------                    Stuart Baumgarten
                                               President


Name:                                     Address: 12601 Research Parkway
                                                   Orlando, Florida 32826


                                          "MORTGAGEE"

                                          SUNTRUST BANK


                                          By:
                                             ----------------------------------
Name:                                        Karen A. Harrington
                                             Assistant Vice President


Name:                              Address:  200 South Orange Ave.
                                             Orlando, Florida 32801



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