EXHIBIT 10.21

                                  EXHIBIT 10.21

SEVEN AMENDMENT TO CREDIT AGREEMENT

THIS SEVEN AMENDMENT TO CREDIT AGREEMENT ("this Amendment") is entered into as
of April 16, 2002, by and between INVIVO CORPORATION, a Delaware corporation
("Borrower"), and XXXXX FARGO BANK, NATIONAL ASSOCIATION ("Bank").

RECITALS

WHEREAS, Borrower is currently indebted to Bank pursuant to the terms and
conditions of that certain Credit Agreement between Borrower and Bank dated as
of October 6, 1998, as amended from time ("Credit Agreement").

WHEREAS, Bank and Borrower have agreed to certain changes in the terms and
conditions set forth in the Credit Agreement and have agreed to amend the Credit
Agreement to reflect said changes.

 NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto agree that the Credit
Agreement shall be amended as follows:

1. Section 1.2 (a) is hereby amended by deleting "Sierra Precision" from the
definition of "Subsidiaries" therein. Bank and Borrower each acknowledge that
Sierra Precision no longer has any of the rights or obligations of a Subsidiary
under the Credit Agreement and that the guaranty by Sierra Precision of, and its
pledge of collateral as security for, the obligations of Borrower to Bank are
hereby released.

2. Section 5.2 is hereby deleted in its entirety, and the following substituted
therefore: "Section 5.2. OTHER INDEBTEDNESS. Create, incur, assume or permit to
exist any indebtedness or liabilities resulting from borrowings, loans or
advances, whether secured or unsecured, matured or unmatured, liquidated or
unliquidated, joint or several, except (a) the liabilities of Borrower or any
Subsidiary to Bank; 9b) the existing liabilities of Invivo Research, Inc. to
SunTrust Bank under a real estate loan incurred in connection with its Orlando,
Florida manufacturing facility; (c) the liabilities of Borrower to Xxxxx Xxxx
incurred in connection with Borrower's purchase of Invivo Research, Inc; (d) any
liabilities of the Subsidiaries to Borrower; (e) new liabilities of Borrower
and/or the Subsidiaries under capital leases in amounts not to exceed an
aggregate of $325,000.00 in any fiscal year; and 9f) any other liabilities of
borrower or any Subsidiaries existing as of, and disclosed to Bank prior to, the
date hereof" 3. Except as specifically provided herein, all terms and conditions
of the Credit Agreement remain in full force and effect, without waiver or
modification. All terms defined in the Credit Agreement shall have the same
meaning when used in this Amendment. This Amendment and the Credit Agreement
shall be read together, as one document. 4. Borrower hereby remakes all
representations and warranties contained in the Credit Agreement and reaffirms
all covenants set forth therein. Borrower further certifies that as of the date
of this Amendment there exists no Event of Default as defined in the Credit
Agreement, nor any condition, act or event which with the giving notice or the
passage of time or both would constitute any such Event of Default.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to executed as
of the day and year first written above.

                                          XXXXX FARGO BANK
INVIVO CORPORATION                        NATIONAL ASSOCIATION

By:_____________________________          By:___________________________
     Xxxxx X. Xxxxxxx                             Xxxxxxx Xxxxxxxx
     President                                    Vice President-Finance

By: _____________________________
       Xxxx X. Xxxxx
       Vice President-Finance


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